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  • 1
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Physics of Plasmas 2 (1995), S. 1332-1342 
    ISSN: 1089-7674
    Source: AIP Digital Archive
    Topics: Physics
    Notes: In modern pulsed power systems the electric field stresses at metal surfaces in vacuum transmission lines are so high that negative surfaces are space-charge-limited electron emitters. These electrons do not cause unacceptable losses because magnetic fields due to system currents result in net motion parallel to the electrodes. It has been known for several years that a parameter known as flow impedance is useful for describing these flows. Flow impedance is a measure of the separation between the anode and the mean position of the electron cloud, and it will be shown in this paper that in many situations flow impedance depends upon the geometry of the transmission line upstream of the point of interest. It can be remarkably independent of other considerations such as line currents and voltage. For this reason flow impedance is a valuable design parameter. Models of impedance transitions and voltage adders using flow impedance will be developed. Results of these models will be compared to two-dimensional, time-dependent, particle-in-cell simulations. © 1995 American Institute of Physics.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Physics of Plasmas 3 (1996), S. 4207-4219 
    ISSN: 1089-7674
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Negative conductors in vacuum transmission lines used in multiterrawatt applications emit electrons freely. These lines are efficient only because the self-magnetic field of the power flow forces the electrons to flow parallel to the electrodes. Excepting numerical simulations, dynamic modeling of systems of these transmission lines has generally either ignored electron flow, or has included only those electrons that cross immediately to the anode at the front of the forward wave. In this paper we describe an analytic model that includes flowing electrons and the effects of these flows on line voltage and on the reduction of magnetic flux. Axial electron currents are modeled using simple, measurable, and calculable parameters. Transverse electron currents are modeled using general patterns found empirically from simulation data. These currents are in turn related by an expanded set of Telegrapher equations. An example of the use of the model is compared to two-dimensional, time-dependent particle-in-cell simulations. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 1471-0528
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Summary. Most of the small increased risk in pelvic inflammatory disease (PID) associated with the intrauterine contraceptive device (IUCD) appears to be caused by bacterial contamination of the endometrial cavity at the time of insertion. This randomized clinical trial of 1813 women in Nairobi, Kenya, assessed the effectiveness of 200 mg of doxycycline given orally at the time of insertion in reducing the occurrence of PID. The rate of this infection in the doxycycline-treated group was 31% lower than that in the placebo-treated group (1.3 and 1.9%, respectively; RR 0.69; 95% CI 0.32 to 1–5). The rate of an unplanned IUCD-related visit to the clinic was also 31% lower in the doxycycline-treated group (RR 0.69; 95% CI 0.52 to 0.91). Although the significance level (P = 0.17) for the reduction is PID does not meet the conventional standard of 0.05, the results may be suggestive of an effect. Moreover, the reduction in IUCD-related visits (P = 0.004) not only represents an important decrease in morbidity but also substantiates the reduction found for PID. Further studies are needed to corroborate these results. Consideration should be given to the prophylactic use of doxycycline at the time of IUCD insertion as an approach to preventing PID and other lUCD-related morbidity.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Annals of the New York Academy of Sciences 112 (1964), S. 0 
    ISSN: 1749-6632
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Natural Sciences in General
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    The @journal of organic chemistry 25 (1960), S. 1055-1056 
    ISSN: 1520-6904
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Biochemistry 30 (1961), S. 579-604 
    ISSN: 0066-4154
    Source: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Topics: Chemistry and Pharmacology , Biology
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Medicine 5 (1954), S. 285-304 
    ISSN: 0066-4219
    Source: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Topics: Medicine
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Oxford, UK; Malden, USA : Blackwell Science Ltd
    Scandinavian journal of immunology 61 (2005), S. 0 
    ISSN: 1365-3083
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Serum procalcitonin (PCT), an accurate marker of severe infection, is moderately increased in chronic kidney disease (CKD), peritoneal dialysis (PD) and haemodialysis (HD). We studied the extent of PCT elevation and factors accounting for elevated PCT in CKD and dialysis, and whether peripheral blood mononuclear cells (PBMC) contribute to increased PCT. In 37 controls, 281 CKD, 31 PD, and 65 HD patients without infection, PCT was measured and correlated with CKD stage, PD, HD, C-reactive protein (CRP), cardiovascular disease (CVD) and other clinical parameters. PCT release by PBMC from controls, advanced CKD, PD and HD patients (12 subjects each) was measured. PCT increased in parallel to the deterioration of CKD. Oliguria, advanced CKD, PD, HD, CVD and elevated CRP were independently associated with PCT elevation. PCT release from PBMC significantly increased in advanced CKD, PD and HD. PCT release from PBMC correlated closely with the corresponding serum PCT values (r = 0.76, P 〈 0.001). In the absence of infection, PCT may increase due to reduced renal elimination and increased synthesis, as due to PBMC. Furthermore, serum PCT could serve as a marker of low-grade inflammation and CVD, which substantially increase mortality in CKD and dialysis.
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Plant, cell & environment 19 (1996), S. 0 
    ISSN: 1365-3040
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: We induced foliar senescence in western larch (Larix occidentalis Nutt.) needles (100 to 400 d old) in chambers set to combinations of photoperiod (8 or 16 h) and air temperature (8 or 15°C). We used regression analysis to estimate the effects of air temperature, photoperiod, provenance and leaf age on the date of decline in chlorophyll, photosynthesis, and chlorophyll a/b ratio. Increased air temperature delayed the decline in chlorophyll and photosynthesis without affecting chlorophyll a/b: seedlings with 200-d-old needles placed under 8h days and 8°C lost chlorophyll, photosynthesis and chlorophyll a/b in 22, 37 and 63d, respectively, while those senescing under 15°C lost them in 54, 61 and 63d. Extended photoperiod delayed the decline in chlorophyll but not photosynthesis or chlorophyll a/b ratio: the 200-d-old needles placed in 8°C and 16 h photoperiod lost chlorophyll, photosynthesis, and chlorophyll a/b in 34, 37 and 63 d, compared with 22, 37 and 63 d for seedlings in 8 h days. Our analysis shows that it is possible to quantify the extent to which the timing and process of senescence vary with environmental conditions.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    Biochemical and Biophysical Research Communications 27 (1967), S. 668-673 
    ISSN: 0006-291X
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Biology , Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
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