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  • 1
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 58 (1985), S. 397-403 
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: An unusual new line has been observed in the low-temperature photoluminescence spectrum of GaAs/AlGaAs epilayers grown by liquid-phase epitaxy, which represents a unique probe of the heterointerface. A very strong, broad and asymmetric line is seen, with peak energy ranging from that of the bound exciton to that of the shallowest acceptor, increasing roughly linearly with the logarithm of the excitation power. The intensity is seen to exhibit a very strong temperature dependence as the temperature is varied from 1.4 K up to about 20 K where the line falls below the background luminescence intensity. Intensity and energy dependence of the luminescence as a function of the Al mole fraction on one side of the junction is also investigated. By employing a novel step-etching technique, this transition is shown to originate from the GaAs/AlGaAs heterojunction. A qualitative model is proposed to explain the observed data.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 57 (1985), S. 2896-2899 
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The photoluminescence of Ge-doped AlxGa1−xAs and Sn-doped GaAs were investigated at 1.4 K. The ionization energy of Ge is strongly dependent on the Al composition in AlGaAs, and is in very poor agreement with the effective mass value. The ionization energy of Sn was found to be 110 meV in contrast with previously reported values. We also report a Sn acceptor bound excitation line at 1.507 eV in Sn-doped GaAs, and a broad luminescence band peaking at ∼1.5 eV in Ge-doped AlGaAs.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Oxford UK : Blackwell Science Ltd
    Journal of oral rehabilitation 28 (2001), S. 0 
    ISSN: 1365-2842
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: The aim of the present study was to compare the activity levels within the two bellies of the lateral pterygoid muscle between different jaw positions to test the hypothesis that the upper head is primarily a stabilizer. Electromyographic (EMG) recordings, using monopolar concentric needle electrodes, were made from 14 healthy subjects during mandibular rest position (RP), clenching in intercuspal position and jaw opening, first about 10 mm and then about 25 mm. Both bellies had very little activity during RP. The activity level of the superior belly was high during clenching and large opening (LO) with a dip during low opening degree. This pattern differed from that of the inferior belly where the activity was relatively low during clenching and then gradually increased to its highest level during LO. The results support that the lower belly is primarily a jaw opener while the superior belly acts as a stabilizer keeping the disc and condyle in a functionally stable position during clenching and jaw movements.
    Type of Medium: Electronic Resource
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  • 4
    ISSN: 1439-0523
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Seven pairs of near-isogenic lines (glandless vs. glanded) and the recurrent parents were used to determine the effects of the dominant glandless gene from ‘Hai 1’(Gossypium barbadense) on agronomic, fibre, and seed characters in Upland cotton, Gossypium hirsutum, backgrounds. The results showed that there were no apparent linkage associations of the glandless gene on most agronomic, fibre and seed characters of Upland cotton, except for seed quality. The glandless line derived from ‘Liaomian 7’had significantly more protein (489.6 g/kg), and that from H237 had significantly more oil (362.4 g/kg) and had the largest oil index (2.70 g) and protein index (3.03 g). The gossypol content of seed in dominant glandless lines in Upland cotton was very low (〈0.04 g/kg). Therefore, it is suggested that the glandless gene can play an important role in breeding glandless or low seed-gossypol Upland cotton cultivars.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Oxford, UK : Munksgaard International Publishers
    Scandinavian journal of medicine & science in sports 12 (2002), S. 0 
    ISSN: 1600-0838
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine , Sports Science
    Notes: During standard graded exercise, blood lactate and blood ammonia levels increase in parallel and the two thresholds appear at the same relative intensity. The first part of this study aimed at comparing ammonia threshold to lactate threshold with five different graded exercise protocols. A significant difference between the two thresholds was found only in the continuous protocol with 4-min steps in which ammonia threshold appeared at a higher intensity than lactate threshold. The second part of the study investigated the correlation of ammonia threshold to some common physiological measurements. Correlation was significant with lactate threshold, ventilation threshold and endurance time. No correlation was found the anaerobic power, anaerobic capacity measurement and peak VO2. Ammonia threshold was also studied before and after endurance training and sprint training. The 8-week endurance training program was able to delay the appearance of ammonia threshold, but not the 8-week sprint training program. Findings in this study demonstrate that ammonia threshold is a physiological parameter that should be recognized and has potential to be applied for the evaluation of exercise capacity and the effectiveness of endurance training programs.
    Type of Medium: Electronic Resource
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  • 6
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Pseudomonas aeruginosa is a ubiquitous environmental bacterium that is one of the top three causes of opportunistic human infections. A major factor in its prominence as a pathogen is its intrinsic resistance to antibiotics and disinfectants. Here we report the complete sequence of P. ...
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Journal of materials science 19 (2000), S. 841-843 
    ISSN: 1573-4811
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Computational optimization and applications 15 (2000), S. 249-268 
    ISSN: 1573-2894
    Keywords: quadratic assignment ; combinatorial optimization ; genetic algorithm ; local search ; k-gene exchange
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Notes: Abstract In this paper, we describe an approach for solving the quadratic assignment problem (QAP) that is based on genetic algorithms (GA). It will be shown that a standard canonical GA (SGA), which involves genetic operators of selection, reproduction, crossover, and mutation, tends to fall short of the desired performance expected of a search algorithm. The performance deteriorates significantly as the size of the problem increases. To address this syndrome, it is common for GA-based techniques to be embedded with deterministic local search procedures. It is proposed that the local search should involve simple procedure of genome reordering that should not be too complex. More importantly, from a computational point of view, the local search should not carry with it the full cost of evaluating a chromosome after each move in the localized landscape. Results of simulation on several difficult QAP benchmarks showed the effectiveness of our approaches.
    Type of Medium: Electronic Resource
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  • 9
    ISSN: 1437-7780
    Keywords: Key words Cefpiramide ; Cephalosporin ; Clinical strains ; MIC
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The in-vitro antibacterial activity of cefpiramide was compared with those of 15 other broad-spectrum cephalosporins. A total of 440 clinical strains of bacteria, including 9 bacterial species, were isolated from our hospital in 1998. The minimum inhibitory concentrations (MICs) of cefpiramide and five other antibiotics were determined for each species, using the agar-dilution method. The MIC of cefpiramide for Escherichia coli and Klebsiella pneumoniae was higher than those of three other third-generation cephalosporins, (ie, cefoperazone, ceftazidime, and ceftriaxone). Fifty-one percent (26/51) of Enterobacter cloacae isolates were resistant to cefpiramide. Cefoperazone/sulbactam and cefepime had greater activity against E. cloacae (resistance, 3.9% and 19.6%, respectively) than cefpiramide. Cefpiramide was more active against Pseudomonas aeruginosa (resistance rates, 12%) than cefoperazone, ceftazidime, ceftriaxone, aztreonam, and cefepime. Cefpiramide-resistant P. aeruginosa strains were resistant to ceftazidime, but 27% of ceftazidime-resistant strains were susceptible to cefpiramide; 15.3% of cefpiramide-resistant S. maltophilia strains were also susceptible to ceftazidime, but 50% of ceftazidime-resistant strains were still susceptible to cefpiramide. Cefoperazone/sulbactam was the most active agent against Acinetobacter baumannii, showing a resistance rate of 2%. Ampicillin/sulbactam, ceftazidime, and cefpiramide were the second most active agents, and about 50% of the tested strains were susceptible to these three antibiotics. Cefpiramide had an activity comparable to that of all tested β-lactams against oxacillin-susceptible Staphylococcus aureus (MIC90, 2 μg/ml). Against Streptococcus pneumoniae and Haemophilus influenzae, cefpiramide had good activity, with an MIC90 concentration at which 90% of the strain was inhibited of 1 μg/ml and 0.5 μg/ml, respectively. These results indicated that cefpiramide was more active against glucose non-fermenting bacteria than against Enterobacteriaceae, and was very active against oxacillin-susceptible Staphylo-coccus aureus, S. pneumoniae, and H. influenzae. Thus, cefpiramide may be a good choice of drug for the treatment of patients with infections with glucose non-fermenting bacteria and community acquired infections.
    Type of Medium: Electronic Resource
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  • 10
    ISSN: 1437-7780
    Keywords: Key words Meropenem ; β-Lactams ; Clinical isolated strains ; MIC (E-test)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract In 1999, a surveillance study was initiated in a hospital in Beijing to monitor the potency and spectrum of five extended-spectrum β-lactam antimicrobial agents (meropenem, imipenem, cefepime, ceftazidime, and cefoperazone/sulbactam) tested against 554 strains of bacteria. Five groups of organisms were tested by the E-test method, with results validated by concurrent quality control strain analysis. Results were tabulated, and 100% of quality assurance tests (16/16 tests) were within ranges recommended by the National Committee for Clinical Laboratory Standards. Of the five β-lactam drugs tested, meropenem and imipenem were the most active against all isolates tested. Overall, the rank order of activity of the five agents was: meropenem (94.6% susceptible) 〉 imipenem (90.1%) 〉 cefepime (77.6%), cefoperazone/sulbactam (77.5%), ceftazidime (76.6%). Ninety-five percent of Enterobacter were to meropenem, while 82% were susceptible to imipenem. Meropenem was more active than imipenem against Pseudomonas aeruginosa. The minimum inhibitory concentration (MIC) of meropenem was eightfold lower than that of imipenem. Meropenem had excellent activity against Haemophilus influenzae, Streptococcus pneumoniae, and oxacillin-susceptible staphylococci.
    Type of Medium: Electronic Resource
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