ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    The controlled rounding problem: Relaxations and complexity issues (1990)
    Springer
    OR spectrum 12 (1990), S. 129-138 
    Details
    ISSN: 1436-6304
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Economics
    Description / Table of Contents: Zusammenfassung Die Technik des „kontrollierten Rundens“ (Controlled Rounding) wird von Behörden wie dem United States Bureau of Census benutzt, um in mehrdimensionalen Tabellen oder Matrizen erfaßte statistische Daten durch Approximation so zu verändern, daß sowohl die Anonymität von Einzeldaten (Matrixeinträgen) als auch die Integrität der Gesamtdaten (Zeilensummen, Spaltensummen etc.) gewährleistet ist. In dieser Arbeit behandeln wir die Komplexität und Lösbarkeit des dreidimensionalen Rundungsproblems und diskutieren eine Hierarchie von Relaxationen, die bei Nichtlösbarkeit des Ausgangsproblems alternative, nahezu zulässige Lösungen liefern.
    Notes: Summary Controlled rounding is a procedure that perturbs tabular data collected from respondents in such a way as to preserve the anonymity of the respondents while maintaining the integrity of the data. Controlled rounding techniques are regularly used by the United States Bureau of the Census and its counterparts in other countries. This paper discusses the complexity of the three-dimensional controlled rounding problem. In particular, the three-dimensional, zero-restricted controlled rounding problem is shown to be NP-complete. As zero-restricted controlled roundings may fail to exist, various relaxations of this basic rounding problem have been defined. The paper introduces a sequence of such relaxations and proceeds to address the existence of solutions and complexity issues for the relaxed problems.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01719708
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Ionospheric convection during the magnetic storm of 20–21 March 1990 (1994)
    Springer
    Annales geophysicae 12 (1994), S. 1174-1191 
    Details
    ISSN: 0992-7689
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract We report on the response of high-latitude ionospheric convection during the magnetic storm of March 20–21 1990. IMP-8 measurements of solar wind plasma and interplanetary magnetic field (IMF), ionospheric convection flow measurements from the Wick and Goose Bay coherent radars, EISCAT, Millstone Hill and Sondrestrom incoherent radars and three digisondes at Millstone Hill, Goose Bay and Qaanaaq are presented. Two intervals of particular interest have been identified. The first starts with a storm sudden commencement at 2243 UT on March 20 and includes the ionospheric activity in the following 7 h. The response time of the ionospheric convection to the southward turning of the IMF in the dusk to midnight local times is found to be approximately half that measured in a similar study at comparable local times during more normal solar wind conditions. Furthermore, this response time is the same as those previously measured on the dayside. An investigation of the expansion of the polar cap during a substorm growth phase based on Faraday’s law suggests that the expansion of the polar cap was nonuniform. A subsequent reconfiguration of the nightside convection pattern was also observed, although it was not possible to distinguish between effects due to possible changes in By and effects due to substorm activity. The second interval, 1200–2100 UT 21 March 1990, included a southward turning of the IMF which resulted in the Bz component becoming -10 nT. The response time on the dayside to this change in the IMF at the magnetopause was approximately 15 min to 30 min which is a factor of \sim2 greater than those previously measured at higher latitudes. A movement of the nightside flow reversal, possibly driven by current systems associated with the substorm expansion phases, was observed, implying that the nightside convection pattern can be dominated by substorm activity.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s00585-994-1174-1
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    NP-completeness of some problems concerning voting games (1990)
    Springer
    International journal of game theory 19 (1990), S. 1-9 
    Details
    ISSN: 1432-1270
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Economics
    Notes: Summary The problem of confirming lower bounds on the number of coalitions for which an individual is pivoting is NP-complete. Consequently, the problem of confirming non-zero values of power indices is NP-complete. The problem of computing the Absolute Banzhaf index is #P-complete. Related problems for power indices are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01753703
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Predictive performance of population pharmacokinetic parameters of tianeptine as applied to plasma concentrations from a post-marketing study (1993)
    Springer
    European journal of clinical pharmacology 45 (1993), S. 123-128 
    Details
    ISSN: 1432-1041
    Keywords: Tianeptine ; anti-depressant ; population pharmacokinetic ; prediction error
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary The predictive ability of population pharmacokinetic parameters of tianeptine, obtained from a mixed effect analysis of pre-marketing pharmacokinetic studies, was evaluated using tianeptine plasma concentrations obtained during a large multi-center post-marketing surveillance study. The mean prediction error was 7.8 ng·ml−1 and the root mean square prediction error was 52.1 ng/ml when initial estimates of population pharmacokinetic parameters were used to predict drug concentrations in one half of the post-marketing data. When the population parameters were revised to reflect the data collected in the first half of the post-marketing study, the mean prediction error was reduced to −3.2 ng·ml−1 and the root mean square prediction error was reduced to 29.5 ng·ml−1. These results suggest that population pharmacokinetic parameters obtained from pre-marketing data may not accurately predict drug concentrations in patients receiving the drug in the post-marketing setting. Once the population parameters are updated to reflect data from the post-marketing period, the predictive ability of the database increases, but substantial variability in the prediction error remains.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00315492
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Development of a population pharmacokinetic database for tianeptine (1993)
    Springer
    European journal of clinical pharmacology 45 (1993), S. 173-179 
    Details
    ISSN: 1432-1041
    Keywords: Tianeptine ; anti-depressant ; NONMEM ; population pharmacokinetic ; pre-marketing database
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary Two thousand three hundred and thirty five plasma concentrations of tianeptine from 112 patients enrolled in nine studies of tianeptine pharmacokinetics performed prior to the marketing of the drug were pooled for analysis using mixed-effect modeling. Studies represented a combination of single dose and multiple dosing at steady-state. Tianeptine plasma concentration time data were fit to a two compartment model with first order absorption using the NONMEM computer program. The results of this analysis suggested that alcoholism is associated with significant increase in clearance (124% increase) and volume of the central compartment (161% increase). The volume of the peripheral compartment is significantly lower in women (31% decrease) and in depressed patients (59% decrease). The population mean (interindividual variability) clearance was equal to 0.17 l·h−1·kg−1 (28.6%), the volume of central compartment was 0.13 l·kg−1 (60.4%), intercompartmental clearance was 0.07 l·h−1·kg−1 (30.1%), volume of the tissue compartment was 1.17 l·kg−1 (28.3%), and the absorption rate constant was 0.63 h−1 (21.8%). The residual variability was approximately 30% at concentrations expected during clinical use of the drug. Because of the increased clearance, alcoholic patients would be expected to have significantly reduced concentrations during steady-state dosing. These population parameters provide a basis for developing initial dosing recommendations and for performing bayesian evaluations of drug concentrations obtained in post-marketing studies.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00315502
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    The excretion of enalapril and enalaprilat in human breast milk (1990)
    Springer
    European journal of clinical pharmacology 38 (1990), S. 99-99 
    Details
    ISSN: 1432-1041
    Keywords: enalapril ; milk ; enalaprilat ; pharmacokinetics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00314815
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Pharmacokinetics of oral acetyl-L-carnitine in renal impairment (1990)
    Springer
    European journal of clinical pharmacology 38 (1990), S. 309-312 
    Details
    ISSN: 1432-1041
    Keywords: Acetyl-L-carnitine ; renal impairment ; pharmacokinetics ; adverse reactions
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary Acetyl-L-carnitine 1.5 g and 3.0 g was administered as three divided doses on each of two occasions to 24 people with varying renal failure (creatinine clearance 127 – 8 ml·min−1). Plasma and urinary concentrations of total-L-carnitine, free (non-esterified) carnitine, short-chain esters and acetyl-L-carnitine were measured. The baseline (pre-study) concentrations of all four substances were related to renal function. Patients whose creatinine clearance was below about 30–40 ml·min−1 were had the highest concentrations. Renal elimination of all four substances was related to dose and to renal function. There was evidence for dose-related elimination, with greater elimination of the larger dose.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00315038
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    The cardiovascular effects of oral nifedipine and nicardipine: A double-blind comparison in healthy volunteers using transthoracic bioimpedance cardiography (1990)
    Springer
    European journal of clinical pharmacology 39 (1990), S. 233-240 
    Details
    ISSN: 1432-1041
    Keywords: nifedipine nicardipine ; transthoracic electrical bioimpedance ; cardiac output ; healthy volunteers
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary The cardiovascular effects of single oral doses of nifedipine (5 and 10 mg) and nicardipine (20 and 30 mg) were compared in a placebo controlled double-blind crossover study involving 8 healthy male volunteers. Two hours following drug administration stroke volume and cardiac index were measured non-invasively using transthoracic electrical bioimpedance cardiography during passive tilting, graded bicycle exercise, and recovery from exercise. Two separate experiments were performed in the absence of active drug to allow the reproducibility of the measurements to be assessed. Coefficients of variation (within experiment/between experiments) for cardiac index were 7.0%/19.9% at rest and 11.5%/9.3% at 180 W exercise. Both nifedipine and nicardipine increased stroke volume and cardiac index and reduced total peripheral resistance (mean blood pressure/cardiac index) at all times in the experiment. Reductions in peripheral resistance were similar for nifedipine 10 mg and nicardipine 20 mg but in these doses slightly larger increases in heart rate were produced by nifedipine, and in stroke volume and cardiac index with nicardipine. The study shows that the cardiovascular effects of nifedipine and nicardipine can be detected using impedance cardiography which is a simple, safe, and inexpensive technique. The differences between the effects of the two drugs were small. Although some were of statistical significance and are consistent with a less marked cardiode-pressant effect for nicardipine, the clinical importance of these observations is uncertain. Further studies to examine the effect of oral nifedipine and nicardipine in patients with impaired ventricular function may be helpful in clarifying this issue.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00315102
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    The human PDGF receptor α-subunit gene maps to chromosome 4 in close proximity to c-kit (1990)
    Springer
    Human genetics 〈Berlin〉 85 (1990), S. 383-385 
    Details
    ISSN: 1432-1203
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The gene encoding the α-subunit of the human platelet-derived growth factor receptor (PDGFRA) maps to band q11–q12 of chromosome 4 by in situ hybridization, which was confirmed by Southern analysis of a Chinese hamster × human cell hybrid that retains only human chromosome 4.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00206767
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Identification and potential use of a molecular marker for rust resistance in common bean (1993)
    Springer
    Theoretical and applied genetics 85 (1993), S. 745-749 
    Details
    ISSN: 1432-2242
    Keywords: Polymerase chain reaction ; Random amplified polymorphic DNA (RAPD) ; Phaseolus vulgaris ; Uromyces appendiculatus ; Gene pyramiding
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The Up 2 gene of common bean (Phaseolus Vulgaris L.) is an important source of dominant genetic resistance to the bean rust pathogen [Uromyces appendiculatus (Pers. ex Pers.) Unger var ‘appendiculatus’ [syn U. Phaseoli (Reben) Wint.]. Up 2 in combination with other rust resistance genes may be used to obtain potentially stable genetic resistance. It is difficult, however, to combine rust resistance genes effective against a single race due to epistatic interactions that frequently occur between them. A strategy that employed bulked DNA samples formed separately from the DNA of three BC6F2 individuals with Up 2 and three without Up 2 as contrasting near-isogenic lines (NILs) was used to identify random amplified polymorphic DNA fragments (RAPDs) tightly linked to the Up 2 locus. Only 1 of 931 fragments amplified by 167 10-mer primers of arbitrary sequence in the polymerase chain reaction (PCR) was polymorphic. The RAPD marker (OA141100) amplified by the 5′-TCTGTGCTGG-3′ primer was repeatable and its presence and absence easy to score. No recombination was observed between OA141100 and the dominant Up 2 allele within a segregating BC6F2 population of 84 individuals. This result suggests that OA141100 and Up 2 are tightly linked. Andean and Mesoamerican bean germ plasm, with and without the Up 2 allele, were assayed for the presence of OA141100. Apparently, the marker is of Andean origin because all Andean lines, with or without the Up 2 allele, contained the marker, and the marker was absent in all Mesoamerican germ plasm except the lines to which Up-2 had been purposely transferred. These results suggest that OA141100 will be most useful for pyramiding Up 2 with other rust resistance genes into germ plasm of Mesoamerican origin where the marker does not traditionally exist. The use of bulked DNA samples may have concentrated resources toward the identification of RAPDs that were tightly linked to the target locus. Marker-based selection may provide an alternative to the time-consuming testcrosses required to pyramid bean rust resistance genes that exhibit epistasis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00225014
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...