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  • 1
    Electronic Resource
    Electronic Resource
    Expression of polyketide biosynthesis and regulatory genes in heterologous streptomycetes (1991)
    Springer
    Journal of industrial microbiology and biotechnology 7 (1991), S. 163-174 
    Details
    ISSN: 1476-5535
    Keywords: Hybrid antibiotics ; Polyketide biosynthesis ; Anthracyclines ; Actinorhodin ; Streptomycetes ; Interspecies gene cloning
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Summary There are now several examples showing that hybrid secondary metabolites can be produced as a result of interspecies cloning of antibiotic biosynthesis genes in streptomycetes. This paper reviews examples of hybrid secondary metabolite production, and examines the underlying biochemical and regulatory principles leading to the formation of hybrid anthraquinones by recombinant anthracycline-producing streptomycetes carrying actinorhodin biosynthesis genes. An anthraquinone, aloesaponarin II, was produced by cloning theactI, actIII, actIV, andactVII genes (pANT12) of actinorhodin biosynthesis pathway fromStreptomyces coelicolor in anthracycline producing streptomycetes.Streptomyces galilaeus strains 31 133 and 31 671, aclacinomycin and 2-hydroxyaklavinone producers, respectively, formed aloesaponarin II as their major polyketide product when transformed with pANT12. Subcloning experiments indicated that a 2.8-kbXhoI fragment containing only theactI andactVII loci was necessary for aloesaponarin II biosynthesis byS. galilaeus 31 133. WhenS. galilaeus 31 671 was transformed with theactI, actVII, andactIV genes, however, the recombinant strain produced two novel anthraquinones, desoxyerythrolaccin and 1-0-methyldesoxyerythrolaccin. WhenS. galilaeus 31671 was transformed with only the intactactIII gene (pANT45), aklavinone was formed exclusively. These experiments indicate a function for theactIII gene, which is the reduction of the keto group at C-9 from the carboxyl terminus of the assembled polyketide to the corresponding secondary alcohol. The effects of three regulatory loci,dauG, dnrR1, andasaA, on the production of natural and hybrid polyketides were also shown.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01575879
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  • 2
    Electronic Resource
    Electronic Resource
    Transcriptional organization and regulation of the nosiheptide resistance gene inStreptomyces actuosus (1991)
    Springer
    Journal of industrial microbiology and biotechnology 8 (1991), S. 1-12 
    Details
    ISSN: 1476-5535
    Keywords: Nosiheptide resistance ; Thiopeptide antibiotics ; Streptomyces ; Antitermination ; Regulation of transcription
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Summary The nosiheptide resistance gene (nshR) and a putative regulatory gene (nshA) are found together on a 2326 bpBamHI-PstI DNA fragment isolated fromStreptomyces actuosus ATCC 25421. The putative regulatory gene,nshA, situated upstream from the nosiheptide resistance gene in the 2326 bp DNA fragment, contains apparent DNA-binding and RNA-binding domains. Interruption ofnshA in the chromosome ofS. actuosus alters nosiheptide production, suggesting thatnshA is involved in regulation of nosiheptide biosynthesis. Two transcription initiation sites were found upstream ofnshA as demonstrated by high-resolution Sl nuclease mapping. A weak transcription start site fornshR was found which initiated transcription from the first nucleotide of the open reading frame. Although a stem-loop structure with apparent termination activity was found betweennshA andnshR, readthrough of transcription betweennshA andnshR was demonstrated by S1 nuclease mapping of the 3′ terminus of thenshA transcript. Time-course S1 experiments of the three promoters (nshA-pl, nshA-p2, nshR-p) indicated highly regulated differential expression of the promoters.nshA-p2 is a strong, constitutive promoter whereasnshA-pl being regulated temporally with maximal activity at 96 h. Approximately 30% of the totalnshA-p1/p2 transcript reads through the terminator and into thenshR gene, accounting for more than half of the total steady-statenshR transcript. The implications of the regulation ofnshA andnshR gene expression, as well as the expression of two other linked genes, are presented.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01575585
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  • 3
    Electronic Resource
    Electronic Resource
    Numerical study for influences of material parameters on hydrostatic bulging of metal sheet (1993)
    Springer
    Acta mechanica solida Sinica 6 (1993), S. 131-144 
    Details
    ISSN: 0894-9166
    Keywords: rigid viscoplastic finite element method ; hydrostatic bulging ; material parameter
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract In this paper, the influences of various material parameters, the hardening exponent (n), the rate sensitivity (m). the thickness anisotropy parameter (R) and the index M in the Hosford and Hill yield function, on the hydrostatic bulging of a circular clamped sheet of ductile metal materials are analysed by introducting a rigid-viscoplastic finite element method. By numerical studies, an empirical relationship within the average limit thickness strain −ɛ 3 αγ* and the material parameters (n andm) is obtained. Besides, it has been found that the influences of surface shapes of the yield function on the average limit thickness strain can be reflected by the Barlat'sP value which represents the effects ofR andM values.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02207441
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  • 4
    Electronic Resource
    Electronic Resource
    Collateral projections of trigeminal ganglion neurons to both the principal sensory trigeminal and the spinal trigeminal nuclei in the rat (1993)
    Springer
    Experimental brain research 93 (1993), S. 205-212 
    Details
    ISSN: 1432-1106
    Keywords: Trigeminal ganglion ; Trigeminal nuclei ; Substance P ; Calcitonin gene-related peptide ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Employing a combination of fluorescent retro grade double labelling and immunofluorescence histo chemistry for substance P (SP) and calcitonin gene-relat ed peptide (CGRP), we examined collateral projections from single neurons in the trigeminal ganglion (TG) of the rat to both the principal sensory trigeminal nucleus (Vp) and the oral, interpolar or caudal subnuclei of the spinal trigeminal nucleus (Vo, Vi or Vc). In the rats that were unilaterally injected with fast blue (FB) into the Vp and with diamidino yellow (DY) into the Vo, Vi or Vc, neurons labelled with FB and/or DY were observed in the TG ipsilateral to the injections. Of the labelled TG neurons, about 2% were double labelled with both trac ers in the rats that were injected with FB into the Vp and with DY into the Vo or Vi, and about 10% were double labelled in the rats that were injected with FB into the Vp and with DY into the Vc. The results indicate that TG neurons sending their axons to the Vp project, by way of axon collaterals, to the Vc more frequently than to the Vo or Vi. Some of the TG neurons double labelled with FB and DY exhibited SP-or CGRP-like immunoreactivity (LI): Of the TG neurons that were double labelled with FB injected into the Vp and with DY injected into the Vo, Vi or Vc, about 38%, 49% and 42%, respectively, displayed SP-LI, and about 54%, 58% and 59%, respectively, showed CGRP-LI. Some of the SP-or CGRP-LI TG neurons that were double labelled with FB and DY were assumed to mediate pain signals to both the Vp and the spinal trigeminal nucleus (Vo, Vi and/or Vc) by way of axon collaterals.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00228387
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  • 5
    Electronic Resource
    Electronic Resource
    Alport syndrome with neurofibromatosis type-I: a case report (1997)
    Springer
    Pediatric nephrology 11 (1997), S. 649-650 
    Details
    ISSN: 1432-198X
    Keywords: Key words: Alport syndrome ; Neurofibromatosis type-I ; Type IV collagen ; Glomerular basement membrane ; Epidermal basement membrane
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract. We report a 9-year-old boy with repeated fractures of the tibia from age 6 months and microscopic hematuria from age 2 years. His maternal family has a history of nephritis and his paternal family has neurofibromatosis type-I (NF-I). The boy’s renal biopsy revealed an irregular attenuation and splitting of the glomerular basement membrane. The skin biopsy was stained with monoclonal antibody against the α5 chain of type IV collagen; the epidermal basement membrane was negative in the boy and segmentally positive in the boy’s mother. We conclude that the patient inherited Alport syndrome from his mother and NF-I from his father. We postulate this was a chance association and that this case does not suggest any relationship between the two diseases.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004670050358
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  • 6
    Electronic Resource
    Electronic Resource
    Specific in vitro phosphorylation of plant eIF2α by eukaryotic eIF2α kinases (1999)
    Springer
    Plant molecular biology 41 (1999), S. 363-370 
    Details
    ISSN: 1573-5028
    Keywords: eukaryotic initiation factor 2 ; phosphorylation ; plant PKR ; translational control
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Phosphorylation of the α subunit of eukaryotic initiation factor 2 (eIF2α) is known to be an important translational control mechanism in all eukaryotes with the major exception of plants. Regulation of mammalian and yeast eIF2α activity is directly governed by specific phosphorylation on Ser-51. We now demonstrate that recombinant wheat wild-type (51S) but not mutant 51-Ala (51A) protein is phosphorylated by human PKR and yeast GCN2, which are defined eIF2α kinases. Further, only wheat wild-type eIF2α is a substrate for plant-encoded, double-stranded RNA-dependent kinase (pPKR) activity. Plant PKR and GCN2 phosphorylate recombinant yeast eIF2α 51S but not the 51A mutant demonstrating that pPKR has recognition site capability similar to established eIF2α kinases. A truncated version of wild-type wheat eIF2α containing 51S but not the KGYID motif is not phosphorylated by either hPKR or pPKR suggesting that this putative eIF2α kinase docking domain is essential for phosphorylation. Taken together, these results demonstrate the homology among eukaryotic eIF2α species and eIF2α kinases and support the presence of a plant eIF2α phosphorylation pathway.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1006379623534
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  • 7
    Electronic Resource
    Electronic Resource
    An INAA study of trace elements in hair samples from two children on different sampling dates (1991)
    Springer
    Journal of radioanalytical and nuclear chemistry 155 (1991), S. 325-333 
    Details
    ISSN: 1588-2780
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Energy, Environment Protection, Nuclear Power Engineering
    Notes: Abstract A study of trace elements in hair samples from two children of different sex on different sampling dates has been carried out using INAA. Using several combinations of irradiation, cooling and counting times, about thirty elements were quantitatively determined. Some conclusions could be drawn from the data obtained.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02163879
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  • 8
    Electronic Resource
    Electronic Resource
    RNAA of trace iridium in Precambrian-Cambrian boundary samples by thiourea type chelate resin separation (1991)
    Springer
    Journal of radioanalytical and nuclear chemistry 151 (1991), S. 107-111 
    Details
    ISSN: 1588-2780
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Energy, Environment Protection, Nuclear Power Engineering
    Notes: Abstract A RNAA procedure is described for the determination of trace Ir in Precambrian-Cambrian boundary samples. After irradiation, the powdered sample is transferred to a graphite crucible to expel the massive silicon with mixed acid (HF−HCl−HNO3) by heating. The residue is then fused with mixed fusion (Na2O2−NaOH) in a muffle furnace at 700°C for 15 minutes. After cooling, the fused mixture is leached with hot water. The final solution is adjusted to pH 1.5–2.0 and then passed through a column filled with thiourea type chelate resin. The resin absorbed with192Ir is measured for 4000–10 000 s by means of SCORPIO-3000 multi-channel computer — Ge(Li) detector system. Experiments with radioactive tracer are carried aout for checking radiochemical separation yield. The accuracy and precision of the method are evaluated by the analysis of U.S. geological SRMs DTS-1 and AG-Bohor-1. The method is used for the determination of trace Ir in several sets of Precambrian-Cambrian boundary samples collected from Yunnan province in China and the Ir anomaly is observed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02040136
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  • 9
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    Unknown
    Energies, Vol. 9, Pages 394: Numerical Study of Solidification in a Plate Heat Exchange Device with a Zigzag Configuration Containing Multiple Phase-Change-Materials (2016)
    MDPI Publishing
    In: Energies
    Details
    Publication Date: 2016-05-25
    Description: Latent heat thermal energy storage (TES) plays an important role in the advocation of TES in contrast to sensible energy storage because of the large storage energy densities per unit mass/volume possible at a nearly constant thermal energy. In the current study, a heat exchange device with a zigzag configuration containing multiple phase-change-materials (m-PCMs) was considered, and an experimental system was built to validate the model for a single PCM. A two-dimensional numerical model was developed using the ANSYS Fluent 14.0 software program. The energy fractions method was put forward to calculate the average Ste number and the influence of Re and Ste numbers on the discharge process were studied. The influence of phase change temperature among m-PCMs on the solidification process has also been studied. A new boundary condition was defined to determine the combined effect of the Re and Ste numbers on the discharging process. The modelling results show that for a given input power, the Ste (or Re) number has a significant impact on the discharging process; however, the period value of inlet velocity has almost no impact on it. Besides, the zigzag plate with m-PCMs has a good impact on the temperature shock as “filter action” in the discharging process.
    Electronic ISSN: 1996-1073
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Published by MDPI Publishing
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  • 10
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    Water, Vol. 8, Pages 286: Isotopic Characterization of River Waters and Water Source Identification in an Inland River, Central Asia (2016)
    MDPI Publishing
    In: Water
    Details
    Publication Date: 2016-07-13
    Description: Understanding runoff generation and dynamics is the basis for water resource management, while water isotopic ratios are a potential tool for studying the mechanism on a large scale. In this paper, spatial variations of δ18O and δD of river water and their sources within a large region of the Tarim River were investigated. The results showed obvious spatial variations of both water isotope values along the river flow direction, and significant seasonal variation occurred within the river water isotopes. This indicated that different proportions of rain and melt water entering river water should lead to spatial variation, and for mid-stream and downstream regions, the transformation relationship between surface water and groundwater should consider less input of melt water. Furthermore, we quantitatively determine the ratio of different water sources using the stable isotope mass balance method and other stable tracer elements. Results showed the contribution of ice-snowmelt water varied from 14.97% to 40.85%, that of rain varied from 9.04% to 54.80%, and that of groundwater varied from 15.34% to 58.85%, and they also showed that baseflow is a factor connecting melt water and groundwater, which meant the Hotan River and the Yarkand River are melt water–dependent rivers, and seasonal precipitation is the main water supply source of baseflow in the Aksu River and the Kaidu River.
    Electronic ISSN: 2073-4441
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Published by MDPI Publishing
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