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  • 1
    Electronic Resource
    Electronic Resource
    On the concept of temperature for a small isolated system (2001)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 114 (2001), S. 6518-6525 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The microcanonical temperature is shown to be a useful concept in calculations of the decay of a small isolated system with well defined energy. A simpler and more transparent description is obtained than in Klots' formulation of finite-heat-bath theory, where the system is represented by a canonical ensemble. As a further illustration of the utility of the microcanonical temperature concept, we discuss a formula derived by Dunbar for the probabilities for excitation of a single oscillator in a collection of harmonic oscillators with well defined total energy. This formula expresses the excitation probabilities in terms of the temperature for a canonical ensemble with mean energy equal to the energy of the system. However, a much improved accuracy is obtained if the canonical temperature and heat capacity are replaced by their microcanonical values. We justify this replacement through a modified derivation, in which the microcanonical temperature appears as the canonical temperature of a fictitious system with level density ρ′(E), the derivative of the level density ρ(E) of the collection of oscillators. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1357794
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  • 2
    Electronic Resource
    Electronic Resource
    Double-blind, placebo-controlled food challenge with apple (2001)
    Copenhagen : Munksgaard International Publishers
    Allergy 56 (2001), S. 0 
    Details
    ISSN: 1398-9995
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: The aim of the study was to develop and evaluate different methods of double-blind, placebo-controlled food challenge (DBPCFC) with apple. Three different DBPCFC models were evaluated: fresh apple juice, freshly grated apple, and freeze-dried apple powder. All challenges were performed outside the pollen season and took place from 1997 to 1999. The freeze-dried apple material was characterized by means of leukocyte histamine release (HR), skin prick test (SPT), and immunoblotting experiments. The study population consisted of birch pollen-allergic patients with a history of rhinitis in the birch-pollen season and positive specific IgE to birch. For comparison of the DBPCFC models, 65 patients with a positive open oral challenge with apple were selected. In the characterization of the freeze-dried apple material, 46 birch pollen-allergic patients were included. The IgE reactivity to apple was evaluated by measurement of specific IgE, HR, and SPT. Golden Delicious apples were used in all experiments. The results of this study showed that it was possible to perform DBPCFC with apple in birch pollen-allergic individuals. The model with freshly squeezed apple juice had a low sensitivity and displayed a high frequency of reactions to placebo, probably due to the ingredients used for blinding. The sensitivity of the models with freshly grated apple and freeze-dried apple powder was 0.74/0.60. An increase in sensitivity is desirable. The freeze-dried apple powder proved to be useful for SPT, HR, and oral challenges, but further investigation of the stability and the allergenic profile of the material is needed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1034/j.1398-9995.2001.056002109.x
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  • 3
    Electronic Resource
    Electronic Resource
    24-h blood pressure and autonomic function is related to albumin excretion within the normoalbuminuric range in IDDM patients (1997)
    Springer
    Diabetologia 40 (1997), S. 718-725 
    Details
    ISSN: 1432-0428
    Keywords: Keywords Ambulatory blood pressure ; autonomic control ; heart rate variability ; spectral analysis ; IDDM ; microalbuminuria ; diabetic nephropathy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Significant changes in both blood pressure, autonomic function and kidney ultrastructure are observed in insulin-dependent diabetic (IDDM) patients with microalbuminuria. Intervention strategies are evaluated at even earlier stages of disease. Identification of patients at risk of developing microalbuminuria must be based on a thorough knowledge of the relations between key pathophysiological parameters in patients with normoalbuminuria. The aim of the present study was to characterize the interactions of urinary albumin excretion (UAE), 24-h ambulatory blood pressure (AMBP), and sympathovagal balance in a large group of normoalbuminuric IDDM patients. In 117 normoalbuminuric (UAE 〈 20 μg/min) patients we performed 24-h AMBP (Spacelabs 90 207), with assessment of diurnal blood pressure and heart rate (HR) variation, and short-term (three times 5 min) power spectral analysis of RR interval oscillations, as well as cardiovascular reflex tests (HR variation to deep breathing, postural HR and blood pressure response). Patients with UAE above the median (4.2 μg/min) had significantly higher 24-h systolic and diastolic AMBP (125 ± 10.1/76 ± 7.2 mmHg) compared to the low normoalbuminuric group (120 ± 8.4/74 ± 5.1 mmHg), p 〈 0.01 and 0.02, respectively. Patients with UAE above the median had significantly reduced short-term RR interval variability including both the high frequency component (5.47 ± 1.36 vs 6.10 ± 1.43 ln ms2), and low frequency component (5.48 ± 1.18 ln ms2 compared to 5.80 ± 1.41 ln ms2), p 〈 0.02 and p = 0.04 (ANOVA). In addition, patients with high-normal UAE had reduced mean RR level (faster heart rates) 916 ± 108 compared to 963 ± 140 ms, p 〈 0.04. These differences were not explained by age, duration of diabetes, gender, level of physical activity, or cigarette smoking. HbA1 c was significantly higher (8.6 ± 1.2 vs 8.2 ± 1.0 %, p = 0.03) in the group with high normal UAE. Comparing normoalbuminuric IDDM patients with UAE above and below the median value, we found significantly higher AMBP in combination with significant differences in sympathovagal balance and significantly poorer glycaemic control in the group with high-normal albumin excretion. Our data demonstrate interactions between albumin excretion, blood pressure, autonomic function, and glycaemic status, already present in the normoalbuminuric range and may describe a syndrome indicative of later complications. [Diabetologia (1997) 40: 718–725]
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s001250050739
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  • 4
    Electronic Resource
    Electronic Resource
    Radiative cooling of fullerene anions in a storage ring (2001)
    Springer
    The European physical journal 17 (2001), S. 189-204 
    Details
    ISSN: 1434-6079
    Keywords: PACS. 36.40.-c Atomic and molecular clusters – 36.40.Cg Electronic and magnetic properties of clusters – 36.40.Qv Stability and fragmentation of clusters – 36.40.Wa Charged clusters – 39.10.+j Atomic and molecular beam sources and techniques
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract: Thermionic emission from hot fullerene anions, CN -, has been measured in an electrostatic storage ring for even N values from 36 to 96. The decay is quenched by radiative cooling and hence the observations give information on the intensity of thermal radiation from fullerenes. The experiments are analysed by comparison with a simulation which includes the quantisation of photon energy and the statistics of emission. Experiments with heating of the molecules with a laser beam confirm the interpretation of the observations in terms of radiative cooling and give an independent estimate of the cooling rate for C60 -. The measured cooling rates agree in general within a factor of two with the prediction from a classical dielectric model of a thermal radiation intensity of ∼ 300 eV/s for C60 at 1 400 K, scaling approximately with the 6th power of the temperature and with the number of atoms in the molecule.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s100530170022
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