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141.
Brubaker’s book Trans is an important intervention in debates about sexual/gender and racial/ethnic identities in a period of generalized identity unsettlement. It challenges us to think precisely about identities and social categories. Thinking with trans proves to be intellectually productive, showing us the similarities and differences between transgender and trans-race. This contribution to the book symposium raises questions about the specificity of Indigenous identities framed by settler-colonial relations. It also discusses transgender in a global context where non-Western identities have been challenged, and where non-Western protagonists have responded to cultural liberalization at times with forms of gender and sexual repression.  相似文献   
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Pine chemicals are co‐products of papermaking that are upgraded into diverse products from inks to adhesives. They can also be utilized for energy purposes. This research investigates the carbon and energy life cycle assessment (LCA) of pine chemicals derived from crude tall oil (CTO). The study goals are to determine the cradle‐to‐gate carbon and energy footprint for CTO‐derived chemicals, compare CTO‐derived chemicals to their likely substitutes, and calculate the carbon and energy effects of shifting CTO resources from current chemical production to biodiesel production. The data collected represent 100% of the U.S. and 90% of the European CTO distillation industry for 2011. This analysis is the first industry‐level LCA of pine chemicals. The carbon footprint for CTO‐derived pine chemical products is 50% lower than the likely mix of alternative products, including hydrocarbon resins for rubber, ink, and adhesive, alkyl succinic anhydride for paper size, and heavy fuel oil for heat. Current and proposed European policies could result in CTO being classified as renewable biomass for energy production, creating incentive to convert CTO into fuel rather than chemicals. The differences in the carbon and energy footprints of utilizing CTO for biodiesel versus chemicals are not meaningful when comparing European CTO biodiesel, which displaces conventional diesel, to European CTO‐derived chemicals, which displace the previously discussed substitutes. Therefore, there is no additional carbon or energy benefit that accrues by diverting CTO from current chemical feedstock applications to use for biodiesel production in Europe.  相似文献   
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C. Moran  D. D. Shaw 《Chromosoma》1977,63(2):181-204
The acridine grasshopper, Caledia captiva exists as two chromosomal races in south-east Queensland. One of these, the Moreton race inhabits the coastal region to the east of the Great Dividing Range. All chromosomes of the complement (2n=11II+XO/XX) have been involved in centromeric rearrangement, which transforms the acro- and telocentric chromosomes into submeta- and metacentric elements. The second, or Torresian race is widely distributed through southern Papua, Arnhem Land, Cape York Peninsula and down the east coast of Australia as far south as Brisbane. This race, which is characterised by a completely acro- and telocentric chromosome complement, approaches the Moreton race in south-east Queensland where the two races are separated by less than 1 km, along a front of at least 150 km. Evidence is presented to show that chromosome introgression is occurring across the contact zone and this takes place in one direction only, namely the Torresian chromosomes are infiltrating into the Moreton race but not reciprocally. Furthermore, the introgression of chromosomes across the zone is limited to certain members of the Torresian complement and even then these successful chromosomes show highly variable degrees of penetrance into the Moreton race. It is proposed that a tension zone exists between these two races which is maintained by the interaction of (a) ecological tolerance differences on either side of the zone and (b) by partial competitive exclusion due to the interracial differences in phenology. This case of parapatric association with limited hybridisation is unique in its clarity due to the marked differences in the appearance of the chromosome complements of these races which permits direct assessment of the behaviour of most members of the genome in hybrids and their derivatives.  相似文献   
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A hybrid zone between the Moreton and Torresian taxa of the grasshopper Caledia captiva in S.E. Queensland has been characterised in terms of allozyme and chromosome variation within the same individuals. — On chromosomal criteria (pericentric rearrangements), the zone is asymmetrical with evidence of high levels of introgression of Torresian chromosomes into the Moreton taxon. This is apparent from the analysis of two independent transects across the hybrid zone. Major changes in chromosomal frequency occur over distances of less than 0.5 km. and the level of introgression differs between the two transects, with much higher levels in the northern Moreton populations, characterised by an acrocentric X-chromosome, when compared with the southern metacentric-X Moreton populations. Chromosome analysis of samples taken from the same transect over two years has revealed no major changes in the structure of the zone. Moreover, a Moreton population located only 0.5 km. from the null point was found to be stable over 6 generations with evidence for a new balanced genome having originated following the differential incorportation of Torresian chromosomes. — Contrary to the chromosomal situation, the same hybrid zone was found to be symmetrical with respect to allozyme variation with evidence of movement of diagnostic alleles in both directions across the zone. The alleles are independent and not tightly linked to any of the pericentric rearrangements. Thus these 5 alleles are acting as markers of the background genome and reveal the relatively free movement of genes which are located outside the pericentric rearrangements. — It is proposed that the hybrid zone in Caledia captiva is unstable and is moving slowly in a westerly direction into the Torresian territory. This is due to the ability of the Moreton taxon to incorporate more readily into its genome those Torresian chromosomes or chromosome segments which increase the fitness of the Moreton taxon. On chromosomal criteria, the Torresian taxon does not share the same capacity. — It is suggested that, so long as the two taxa retain their ability to hybridise with subsequent asymmetrical introgression, the zone will continue to move westwards and eventually lead to the selective incorporation of the Torresian genome into the Moreton taxon. This will result in a polymorphic situation with clinal variation in chromosomal frequencies. The structure of the zone is dependent upon a fine balance between genomic reorganisation in recombinant genotypes and the relative dispersal capacities of the two hybridising taxa.  相似文献   
146.
Sodium dodecyl sulfate-polyacrylamide gel electrophoresis was used to analyze the macromolecular heterogeneity of lipopolysaccharides (LPS) from seven fresh clinical isolates and three culture collection strains of the human pathogen Helicobacter pylori. All the clinical isolates produced smooth-form LPS with O side chains of relatively homogeneous chain length, whereas the culture collection strains yielded rough-form LPS. A better yield of the latter LPS was obtained when combined protease pretreatment and hot phenol-water extraction were used than when the conventional phenol-water technique alone was used for extraction. The LPS of the three culture collection strains (S-24, C-5437, and NCTC 11637) were chemically characterized. Constituents common to all the LPS were fucose, D-mannose, D-glucose, D-galactose, D-glycero-D-manno-heptose, L-glycero-D-manno-heptose, and 3-deoxy-D-manno-2-octulosonic acid. The molar ratios of the hexoses differed between different strains, thereby reflecting structural differences. Phosphate, phosphorylethanolamine, and pyrophosphorylethanolamine were present also. Free lipid A contained D-glucosamine and fatty acids, with phosphate and a minor amount of ethanolamine. The major fatty acids were ester- and amide-bound 3-hydroxyoctadecanoic acid and ester-bound octadecanioc and 3-hydroxyhexadecanoic acids, with minor amounts of ester-bound tetradecanoic and hexadecanoic acids. In addition to the uncommonly long 3-hydroxy fatty acids, an unusual phosphorylation pattern was deduced to be present in the lipid A.  相似文献   
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When females of the DDK inbred mouse strain are mated to males of other strains, 90-100% of the resulting embryos die during early embryonic development. This DDK syndrome lethality results from incompatibility between an ooplasmic DDK factor and a non-DDK paternal gene, which map to closely linked loci on chromosome 11. It has been proposed that the expression of the gene that encodes the ooplasmic factor is subject to allelic exclusion in oocytes. Previous studies have demonstrated the existence of recessive modifiers that increase lethality in the C57BL/6 and BALB/c strains. These modifiers are thought to skew the choice of allele undergoing allelic exclusion in the oocytes of heterozygous females. In the present study, we demonstrate the presence of modifiers in three Mus musculus domesticus wild-derived strains, PERA, PERC, and RBA. These modifiers completely rescued DDK syndrome lethality. We mapped the major locus that is responsible for rescue in PERA and PERC crosses to proximal chromosome 13 and named this locus Rmod1 (Rescue Modifier of the DDK Syndrome 1). Our experiments demonstrate that PERA or PERC alleles at Rmod1 rescue lethality independently of allelic exclusion. In addition, rescue of the lethal phenotype depends on the parental origin of the Rmod1 alleles; transmission through the dam leads to rescue, while transmission through the sire has no effect.  相似文献   
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