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  • 1
    Electronic Resource
    Electronic Resource
    Infrared-reflection characterization of sintered SiC thermoelectric semiconductors with the use of a four-component effective medium model (1999)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 85 (1999), S. 6728-6737 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Infrared (IR) reflection spectra of sintered SiC thermoelectric semiconductors are studied as a function of doping concentration as well as of sintering temperature. Attention is focused on the changes in the reststrahlen band. The peak and dip frequencies remain constant, implying we are probing stable optical phonon mode in the crystalline grains through the interaction with IR photons. In contrast, variation of spectral shape, including the peak and background reflectance seems to give valuable information regarding the quality of the sintered samples and dopant distribution within the crystal grains and grain boundaries. Measured spectra are analyzed by the use of a four-component effective medium model. In this model we assume the presence of: (1) pores, (2) intergranular materials, (3) crystalline grains, and (4) metallic inclusions (at higher doping levels of metallic impurities), with volume fractions fi(i=1–4), respectively. For frequency dependent complex dielectric functions we employed: (a) a single oscillator model appropriate to the single crystal for the crystalline grains, (b) a Drude model for the metallic inclusions, and assumed (c) another single oscillator model for the intergranular material. The parameters of the latter are determined to give a best fit to the spectrum of a low doping level sample. This model gives excellent overall fit to measured spectra with the ratio f2/f3 and the damping coefficients for the oscillators as adjustable parameters when the experimental estimates for the fraction of pores f1 and metallic inclusions f4 are used. This is remarkable in view of the situation that similar data could not, so far, be explained in terms of the simple Maxwell–Garnet model. The results suggest that careful analyses of spectral shape of IR reflection in the optical phonon resonance region can be used to get information on the intergranular to grain ratio or on the damping coefficients, which are related to the quality of sintered samples or to the distribution of doped impurities among grains and grain boundaries. The background reflectance also give information on the presence of metallic inclusions although the effects of scattering may affect the interpretation. These results combined with the possibility of local probing seems to imply that IR reflectance can offer a versatile means to check the quality of the sintered samples. © 1999 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.370186
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  • 2
    Electronic Resource
    Electronic Resource
    Vector model analysis in nondestructive imaging by using the photothermal deflection methods (1999)
    Springer
    Applied physics 69 (1999), S. 343-346 
    Details
    ISSN: 1432-0630
    Keywords: PACS: 78.20.Hp; 42.30.Va; 65.90.+i
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract. The noncontact imaging of the buried structures is carried out in the open-air atmosphere by using the photothermal deflection (PTD) method. We applied these techniques to the layered samples. Besides the PTD images for the optically opaque buried structures, the parameters of the materials such as thermal diffusivity can also be calculated from the PTD amplitude and phase signal in the PTD scanning images. When the PTD signals at two different modulation frequencies are used, the thermal diffusivity of the buried structure can be obtained from the PTD signal outside of the sample nondestructively.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s003390051011
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  • 3
    Electronic Resource
    Electronic Resource
    Dietary Restriction Reduces the Prevalence of Osteonecrosis of the Caput Femoris in Spontaneously Hypertensive Rats (1999)
    Springer
    Calcified tissue international 64 (1999), S. 259-262 
    Details
    ISSN: 1432-0827
    Keywords: Key words: Spontaneously hypertensive rat — Osteonecrosis — Caput femoris — Dietary restriction — Mechanical stress — Blood supply.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Abstract. We investigated the effects of dietary restriction (DR), an experimental intervention known to suppress several strain-specific diseases, on the prevalence of osteonecrosis of the caput femoris in spontaneously hypertensive rats (SHR). At 6 weeks of age, the food intake of DR rats was restricted to 65% of the mean intake of control rats fed ad libitum (AL). Acute osteonecrosis of the caput femoris without reparative tissue response (RTR) was observed at 10 and 15 weeks in both DR and AL groups; no such acute lesion was seen at 20 and 30 weeks. The prevalence of osteonecrosis, osteonecrosis with/without reparative tissue response was significantly reduced in DR rats at 15 and 20 weeks, but not at 10 weeks. DR reduced the body weight by 30% and the length of the femur by 10%. Ossification of the caput femoris, known to be delayed in AL rats compared with Wistar Kyoto rats, was also restored by DR. Our results showed that dietary restriction reduced the prevalence of osteonecrosis and modulated the mechanical factors involved in the lesion. They also indicate that utilization of dietary restriction is a useful research tool for investigating the underlying mechanisms of osteonecrosis of the caput femoris in SHR.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002239900614
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  • 4
    Electronic Resource
    Electronic Resource
    Confirmation of primitive chromosome structure in the hexaploid wheats (1988)
    Springer
    Theoretical and applied genetics 75 (1988), S. 717-719 
    Details
    ISSN: 1432-2242
    Keywords: Hexaploid wheats ; Primitive chromosome structure ; Translocation ; Chinese Spring ; Triticum dicoccoides
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Hybrids between Triticum aestivum cv Chinese Spring (CS) and T. dicoccoides of chromosome type E1a showed only a few or no trivalents at meiosis, but both trivalents and quadrivalents were shown by hybrids with six other types. Since there is strong evidence that the E1a type has the primitive chromosome structure of T. dicoccoides, Chinese Spring can be said to have the primitive chromosome structure of the hexaploid wheats in regard to reciprocal translocation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00265592
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  • 5
    Electronic Resource
    Electronic Resource
    C-banding analysis on wild Emmer (Triticum dicoccoides Körn) strains with and without spontaneous reciprocal translocations (1996)
    Springer
    Theoretical and applied genetics 92 (1996), S. 173-178 
    Details
    ISSN: 1432-2242
    Keywords: Key words Triticum dicoccoides  ;  Reciprocal translocation  ;  Translocation breakpoint  ;  C-banding
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract  C-banding polymorphism was analyzed in eight strains of wild Emmer, Triticum dicoccoides Körn, which included six translocation homozygotes reported previously. Polymorphisms were detected in all of the strains examined, and the breakpoints of five spontaneous translocations were successfully identified by Cbands. Of the eight breakpoints that could be precisely identified, one was located in the centromeric region while the remaining seven were located in proximal to distal euchromatic regions. The two breakpoints of one translocation could only be approximately localized to proximal regions due to the scarcity of C-bands. The present results are in contrast with those observed on T. araraticum, another wild tetraploid wheat belonging to the Timopheevi group, in which most of the breakpoints were located in centromeric regions. In T. dicoccoides, the six translocation chromosome types were derived from the standard karyotype primarily by a mechanism other than centric breakage-fusion.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s001220050111
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  • 6
    Electronic Resource
    Electronic Resource
    C-banding analysis on wild Emmer (Triticum dicoccoides Körn) strains with and without spontaneous reciprocal translocations (1996)
    Springer
    Theoretical and applied genetics 92 (1996), S. 173-178 
    Details
    ISSN: 1432-2242
    Keywords: Triticum dicoccoides ; Reciprocal translocation ; Translocation breakpoint ; C-banding
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract C-banding polymorphism was analyzed in eight strains of wild Emmer, Triticum dicoccoides Körn, which included six translocation homozygotes reported previously. Polymorphisms were detected in all of the strains examined, and the breakpoints of five spontaneous translocations were successfully identified by C-bands. Of the eight breakpoints that could be precisely identified, one was located in the centromeric region while the remaining seven were located in proximal to distal euchromatic regions. The two breakpoints of one translocation could only be approximately localized to proximal regions due to the scarcity of C-bands. The present results are in contrast with those observed on T. araraticum, another wild tetraploid wheat belonging to the Timopheevi group, in which most of the breakpoints were located in centromeric regions. In T. dicoccoides, the six translocation chromosome types were derived from the standard karyotype primarily by a mechanism other than centric breakage-fusion.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00223373
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  • 7
    Electronic Resource
    Electronic Resource
    Molecular phylogeny of Dipterocarpaceae in Southeast Asia using RFLP of PCR-amplified chloroplast genes* (1996)
    Springer
    Theoretical and applied genetics 93 (1996), S. 22-29 
    Details
    ISSN: 1432-2242
    Keywords: Key words Dipterocarpaceae  ;  PCR-RFLP Chloroplast gene  ;  Phylogeny  ;  Southeast Asia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract  Dipterocarpaceae is the dominant family of Southeast Asia’s climax tropical rain forest region, and it contains the region’s most important commercial timber species. A molecular phylogeny of the Dipterocarpaceae subfamily Dipterocapoideae was constructed using restriction fragment length polymorphisms of polymerase chain reaction-amplified specific genes in chloroplast DNA. A total of 141 site changes were detected among ten genera and 30 species in 11 different genes: rbcL, psbA, psbD, rpoB, rpoC, petB, atpH, 16S, psaA, petA and trnK. Phylogenetic trees constructed by Wanger parsimony and neighbor-joining methods, using Upuna as the outgroup, displayed five monophytelic groups that included Upuna: HopeaShorea-Parashorea-Neobalanocarpus; Dryobalanops; Dipterocarpus; Anisoptera-Vatica-Cotylelobium; and Upuna. The phylogenetic trees clearly separate species with two different base chromosome numbers: the first group is and the other is The group is thought to be in a synapomorphic character state. Parashorea lucida is a sister to most Shorea species. Neobalanocarpus heimii and Hopea from a clade of a sister to two Shorea species, and Cotylelobium and Vatica are closely related species. Our conclusions agree with a phylogeny derived from wood anatomy data analysis, and with Symington’s and Ashton’s taxonomic classifications.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s001220050242
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  • 8
    Electronic Resource
    Electronic Resource
    Molecular phylogeny of Dipterocarpaceae in Southeast Asia using RFLP of PCR-amplified chloroplast genes (1996)
    Springer
    Theoretical and applied genetics 93 (1996), S. 22-29 
    Details
    ISSN: 1432-2242
    Keywords: Dipterocarpaceae ; PCR-RFLP Chloroplast gene ; Phylogeny ; Southeast Asia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Dipterocarpaceae is the dominant family of Southeast Asia's climax tropical rain forest region, and it contains the region's most important commercial timber species. A molecular phylogeny of the Dipterocarpaceae subfamily Dipterocapoideae was constructed using restriction fragment length polymorphisms of polymerase chain reaction-amplified specific genes in chloroplast DNA. A total of 141 site changes were detected among ten genera and 30 species in 11 different genes: rbcL, psbA, psbD, rpoB, rpoC, petB, atpH, 16S, psaA, petA and trnK. Phylogenetic trees constructed by Wanger parsimony and neighbor-joining methods, using Upuna as the outgroup, displayed five monophytelic groups that included Upuna: HopeaShorea-Parashorea-Neobalanocarpus; Dryobalanops; Dipterocarpus; Anisoptera-Vatica-Cotylelobium; and Upuna. The phylogenetic trees clearly separate species with two different base chromosome numbers: the first group is x=7, and the other is x=11. The x=7 group is thought to be in a synapomorphic character state. Parashorea lucida is a sister to most Shorea species. Neobalanocarpus heimii and Hopea from a clade of a sister to two Shorea species, and Cotylelobium and Vatica are closely related species. Our conclusions agree with a phylogeny derived from wood anatomy data analysis, and with Symington's and Ashton's taxonomic classifications.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00225722
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  • 9
    Electronic Resource
    Electronic Resource
    A linkage map for sugi (Cryptomeria japonica) based on RFLP, RAPD, and isozyme loci (1995)
    Springer
    Theoretical and applied genetics 90 (1995), S. 835-840 
    Details
    ISSN: 1432-2242
    Keywords: RFLP ; RAPD ; Linkage map ; Sugi (Cryptomeria japonica) ; Three-generation pedigree
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A linkage map for sugi was constructed on the basis of restriction fragment length polymorphism (RFLP), random amplified polymorphic DNA (RAPD), and isozyme loci using a three-generation pedigree prepared for genetic analysis of heartwood color. A total of 128 RFLP (123 cDNA and 5 genomic probes), 33 RAPD, 2 isozyme, and 1 morphological (dwarf) loci segregated in 73 progeny. Of the 164 segregating loci, 145 loci were distributed in 20 linkage groups. Of these loci, 91 with confirmed map positions were assigned to 13 linkage groups, covering a total of 887.3 cM. A clustering of markers with distorted segregation was observed in 6 linkage groups. In the four clusters, distortions with a reduction in the number of homozygotes from one parent only were found.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00222019
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  • 10
    Electronic Resource
    Electronic Resource
    Detection of quantitative trait loci for juvenile growth, flower bearing and rooting ability based on a linkage map of sugi (Cryptomeria japonica D. Don) (1998)
    Springer
    Theoretical and applied genetics 97 (1998), S. 45-50 
    Details
    ISSN: 1432-2242
    Keywords: Key words Linkage map ; QTL ; Juvenile growth ; Flower bearing ; Cryptomeria japonica D. Don
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract  Quantitative traits, including juvenile growth, flower bearing and rooting ability, of a woody plant species, Cryptomeria japonica D. Don, were analyzed in a three-generation pedigree with 73 F2 progenies using a linkage map with 85 genetic markers (72 RFLP, 11 RAPD, one isozyme and one morphological loci). A cluster of quantitative trait loci (QTLs) related to juvenile growth and female flower bearing was detected on linkage group 2. Some of the influence of this cluster could be attributed to pleiotropic effects of a dwarf locus located in its vicinity. QTLs related to male and female flower bearing were detected at different locations and showed different effects from each other, suggesting that the genetic systems controlling male and female flowering are different. No large QTL affecting rooting ability was detected in the material analyzed in this study.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s001220050865
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