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1.
Jason Sumich 《Ethnos》2016,81(5):821-841
In this essay, I examine the moral basis of a ‘middle class’ in Maputo, Mozambique, the narratives, forms of dependence and types of hegemony that the social hierarchy rests upon. I argue that the political and economic processes that have given rise to ‘new’ middle classes in the global south also create conditions of precariousness. In recent years, it has been argued that these ‘emerging middle classes’ are central for economic growth and the safeguarding of a stable, liberal order. The case of Mozambique complicates this assertion and demonstrates an occurrence now taking place across the globe. When the relationships of dependence and obligation and the narratives that justify them erode, the structures of power that may have once been mutually constitutive between an emerging middle class and the state can become damaging as the system they once upheld loses its legitimacy. 相似文献
2.
Molecular analysis of deficient class I H-2 antigen expression by mouse lung carcinoma cells 总被引:3,自引:0,他引:3
D W Bahler K M Cerosaletti E M Lord J G Frelinger 《Journal of immunology (Baltimore, Md. : 1950)》1988,140(11):4003-4012
We have continued our investigations of line lung carcinoma cells to understand the molecular basis of decreased expression of class I H-2 Ag and class I Ag induction with DMSO. We show that line 1, a murine lung carcinoma cell line, has low levels of class I Ag (H-2K, D, and L) because it is deficient in both class I and beta 2-microglobulin (B2M) RNA, and that these mRNA can be coordinately induced with DMSO. Evidence presented herein also shows that IFN-gamma can induce surface expression of class I Ag and suggests that it may act through a different mechanism than DMSO in inducing class I Ag. To further evaluate the regulation of class I expression, H-2Dp genes were transfected into line 1 cells. The transfected H-2 genes appear to be constitutively expressed at much higher levels than are the endogenous class I genes because surface expression of the foreign Dp Ag on the transfectants is elevated relative to the endogenous H-2d haplotype class I Ag. Both Dp surface expression and Dp mRNA are induced after treatment with DMSO. In all the Dp transfectants, we observed higher constitutive levels of class I mRNA as well as increased constitutive levels of endogenous B2M mRNA when compared to control or untransfected line 1 cells, however, we could not correlate these constitutive levels with Dp copy number. These results suggest that the regulation of class I and B2M genes is linked and that expression of class I genes can affect the expression of B2M genes. 相似文献
3.
The subcellular location of class I H-2 histocompatibility antigens was determined for mouse liver using immunocytochemical techniques and correlated with information determined by cell fractionation and analysis in situ. Surface antigens first were localized by standard procedures involving surface labeling with ferritin-labeled antibody. This approach could not be used for internal membranes either in situ or in fractions since the antigens are not expressed at the cytoplasmic surface. For this purpose, thin sections of tissues embedded in Lowicryl were analyzed and quantitated. The in situ analysis confirmed the presence of H-2 antigens on internal membrane compartments as well as on the cell surface and helped rule out the possibility that distributions based on analyses by immunoprecipitation of fractions of internal membranes were influenced greatly by plasma membrane contamination. Quantitation was provided by immunoprecipitation of H-2 antigens from radioiodinated or metabolically labeled isolated and highly purified cell fractions. The findings establish the presence of class I H-2 histocompatibility antigens in endoplasmic reticulum, Golgi apparatus and plasma membrane in the approximate ratios of 1:3:7. No class I H-2 histocompatibility antigens could be detected in mitochondria, salt extracts of isolated membranes or NP-40-insoluble membrane material. 相似文献
4.
Chemicals on plant surfaces as a heretofore unrecognized,but ecologically informative,class for investigations into plant defence
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Eric F. LoPresti 《Biological reviews of the Cambridge Philosophical Society》2016,91(4):1102-1117
Plants produce and utilize a great diversity of chemicals for a variety of physiological and ecological purposes. Many of these chemicals defend plants against herbivores, pathogens and competitors. The location of these chemicals varies within the plant, some are located entirely within plant tissues, others exist in the air‐ (or water‐) space around plants, and still others are secreted onto plant surfaces as exudates. I argue herein that the location of a given defensive chemical has profound implications for its ecological function; specifically, I focus on the characteristics of chemical defences secreted onto plant surfaces. Drawing from a broad literature encompassing ecology, evolution, taxonomy and physiology, I found that these external chemical defences (ECDs) are common and widespread in plants and algae; hundreds of examples have been detailed, yet they are not delineated as a separate class from internal chemical defences (ICDs). I propose a novel typology for ECDs and, using existing literature, explore the ecological consequences of the hypothesized unique characteristics of ECDs. The axis of total or proportional investment in ECDs versus ICDs should be considered as one axis of investment by a plant, in the same way as quantitative versus qualitative chemical defences or induced versus constitutive defences is considered. The ease of manipulating ECDs in many plant systems presents a powerful tool to help test plant defence theory (e.g. optimal defence). The framework outlined here integrates various disciplines of botany and ecology and suggests a need for further examinations of exudates in a variety of contexts, as well as recognition of the effects of within‐plant localization of defences. 相似文献
5.
Niehaus I 《Culture, medicine and psychiatry》2012,36(2):327-347
Durkheim's classical theory of suicide rates being a negative index of social solidarity downplays the salience of gendered concerns in suicide. But gendered inequalities have had a negative impact: worldwide significantly more men than women perpetrate fatal suicides. Drawing on narratives of 52 fatal suicides in Bushbuckridge, South Africa, this article suggests that Bourdieu's concepts of 'symbolic violence' and 'masculine domination' provide a more appropriate framework for understanding this paradox. I show that the thwarting of investments in dominant masculine positions have been the major precursor to suicides by men. Men tended to take their own lives as a means of escape. By contrast, women perpetrated suicide to protest against the miserable consequences of being dominated by men. However, contra the assumption of Bourdieu's concept of 'habitus', the narrators of suicide stories did reflect critically upon gender constructs. 相似文献
6.
Mutually exclusive splicing of alpha-tropomyosin exons enforced by an unusual lariat branch point location: implications for constitutive splicing 总被引:44,自引:0,他引:44
Alternative splicing of alpha-tropomyosin pre-mRNA involves mutually exclusive utilization of exons 2 and 3, exon 3 being preferentially selected in most cells. This mutually exclusive behavior is enforced by absolute incompatibility between the adjacent splice sites of the two exons, due to close proximity of the exon 3 branch point to exon 2. The branch point, with an associated polypyrimidine tract, is in an unusual location, 177 nt upstream of the acceptor, only 42 nt from the exon 2 splice donor site. Splicing of exon 2 to 3 is consequently blocked prior to formation of an active spliceosome complex. This block to splicing can be relieved by insertion of spacer elements that increase the donor site-branch point separation to 51-59 nt. The unconventional relative location of the constitutive cis splicing elements therefore provides a simple mechanistic basis for strict mutually exclusive splicing. These results not only demonstrate that the branch point is not specified by proximity to the splice acceptor site, but rather suggest that it is the acceptor site which is specified relative to the branch point. 相似文献
7.
Mutually exclusive splicing of the insect Dscam pre-mRNA directed by competing intronic RNA secondary structures 总被引:9,自引:0,他引:9
Graveley BR 《Cell》2005,123(1):65-73
Drosophila Dscam encodes 38,016 distinct axon guidance receptors through the mutually exclusive alternative splicing of 95 variable exons. Importantly, known mechanisms that ensure the mutually exclusive splicing of pairs of exons cannot explain this phenomenon in Dscam. I have identified two classes of conserved elements in the Dscam exon 6 cluster, which contains 48 alternative exons--the docking site, located in the intron downstream of constitutive exon 5, and the selector sequences, which are located upstream of each exon 6 variant. Strikingly, each selector sequence is complementary to a portion of the docking site, and this pairing juxtaposes one, and only one, alternative exon to the upstream constitutive exon. The mutually exclusive nature of the docking site:selector sequence interactions suggests that the formation of these competing RNA structures is a central component of the mechanism guaranteeing that only one exon 6 variant is included in each Dscam mRNA. 相似文献
8.
Satnam Virdee 《Ethnic and racial studies》2013,36(13):2259-2266
In this essay, I respond to the reviewers of my book, Racism, Class and the Racialized Outsider, including Bhattacharrya, Frost, Jefferys, Meer, Roediger and van der Linden. In particular, I elaborate further on the epistemological foundations of the book, including my aim to stretch the concept of working class to accommodate both ethnic diversity, and the significance of racism and anti-racism within it. Then, I state the case for how the concept of the racialized outsider can help transform our understanding of the key signposts of English working-class history. The significance of the anti-racist accomplishments of the 1970s and 1980s are also given further consideration alongside the relevance of the book and its arguments to the present environment – a period where those accomplishments have started to be reversed. 相似文献
9.
K Ohnishi 《Nucleic acids symposium series》1983,(12):91-94
Published sequence data of MHC genes, cDNAs and MHC products were analyzed for their sequence homologies. Alignment statistics revealed that class I gene products consist of four mutually homologous domains, and that class II beta gene products is composed of three mutually homologous domains. Not only extracellular domains but also newly discovered C-terminal shorter domains of class I and class II beta gene products were found to have evolved from a one-domain-long beta 2-microglobulin-like protein by repeated exon duplications and splittings. 相似文献
10.
Rupert Stasch 《Ethnos》2015,80(4):433-447
ABSTRACTA growing body of ethnographic work examines tourism in which visited people are figured as embodying an archaic human condition outside modernity. I suggest that this work's core subject is the structure of articulations between people who understand their close involvement very differently. I then highlight two more specific themes that cut across this issue's case studies from Kenya, Indonesia, China, and Papua New Guinea. One is that ethnographers trace participants' disparate understandings of specific interactional media, since these contact points and their plural make-up are the actual substance of articulation between different sides to the encounters. The other theme I highlight is that heterogeneity within tourists' and visited people's home ideological formations is critical to their tourism involvement, such that endosocial and exosocial processes are mutually constitutive. I lastly outline how the category ‘primitivism’ is a useful resource for situating this tourism in wider and deeper historical contexts. 相似文献
11.
Marion Godman 《Biology & philosophy》2018,33(3-4):21
Is there anything that members of each binary category of gender have in common? Even many non-essentialists find the lack of unity within a gender worrying as it undermines the basis for a common political agenda for women. One promising proposal for achieving unity is by means of a shared historical lineage of cultural reproduction with past binary models of gender (e.g. Bach in Ethics 122:231–272, 2012). I demonstrate how such an account is likely to take on board different binary and also non-binary systems of gender. This implies that all individuals construed as members of the category, “women” are in fact not members of the same historical kind after all! I then consider different possible means of modifying the account but conclude negatively: the problem runs deeper than has been appreciated thus far. 相似文献
12.
Peter Wade 《Ethnic and racial studies》2013,36(7):1169-1173
White working-class people have been portrayed in the media and political discourse as unable to keep pace with the demands associated with living in multicultural Britain. In this article, I shall challenge such representations of white working-class people's attitudes towards racialized ‘others’. To do this I explore the views of the members of a white working-class family to the changing racial composition of their once ethnically homogenous council estate (municipal housing). My ethnographic attention is directed to the connections, affective ties and emotional investments that the members of this family have with the estate and its community, and the ways in which BrAsians become configured in these narratives of belonging. I will show how analytical attention to the connections and attachments that white working-class people form with those whom they identify as ethnic and racial ‘others’ provides an account of white working-class identities that undermines popular representations of ‘them’. 相似文献
13.
Endocytosis and dissociation of class I MHC molecules labeled with fluorescent beta-2 microglobulin 总被引:1,自引:0,他引:1
J H Hochman H Jiang L Matyus M Edidin B Pernis 《Journal of immunology (Baltimore, Md. : 1950)》1991,146(6):1862-1867
Membrane class I MHC molecules of Con-A activated and lymphoma murine cells have been labeled by exchange of the cell's beta 2m with soluble fl-beta 2m. It has previously been shown that this method of labeling is specific and does not affect the biologic properties of class I MHC Ag. With this labeling it has been possible to demonstrate the constitutive endocytosis of class I MHC by fluorescence microscopy and by measuring the resistance to quenching by crystal violet of the internalized fl-beta 2m molecules. We could also follow the kinetics of beta 2m dissociation from the class I molecules at different pH. At pH 5.5, that is the average pH of endosomes, there is considerable dissociation within 15 to 20 min, that is the average recycling half time of class I MHC containing endosomes in activated T cells. Inasmuch as the process is reversible it is likely that, in the recycling endosomes of T cells, class I MHC molecules undergo conformational changes with beta 2m going off and on and with consequent changes of the peptide binding site. This process might be involved in Ag presentation, but, because it is apparently limited to T cells, it would play a role in the presentation of the cell's own TCR in idiotypic interactions between T cells. 相似文献
14.
Leech saliva is shown to contain protein platelet aggregation inhibitors and a range of selective low molecular weight (LMW) aggregation inhibitors. Gel filtration on Bio-Gel P-2 (cut-off kDa) yields a protein fraction (Fr. I) and three LMW fractions. Fr. I inhibits aggregation induced by collagen, ADP, epinephrine and arachidonic acid. Of all the fractions, only one, Fr. II (LMW) specifically inhibits aggregation induced by platelet activating factor (PAF, 1-O-alkyl-2-acetyl-sn-glycero-3-phosphorylcholine). Fr. II also inhibits thrombin-induced platelet aggregation. Fr. III inhibits aggregation induced by ADP, epinephrine and arachidonic acid, and Fr. IV only that induced by arachidonic acid. Fr. II also inhibits PAF- and thrombin-induced thromboxane generation in platelets, but does not inhibit arachidonic acid-induced thromboxane generation. Efforts to separate the anti-PAF from the anti-thrombin activity have been unsuccessful. The inhibition may therefore be due to a single inhibitor, though it may also be due to several inhibitors. Fr. II also inhibits superoxide anion production in formyl Met-Leu-Phe (fMLP)- and ionophore 23187- stimulated neutrophils. This may be due to the inhibition of the effects of PAF generated within the cell. Preliminary results suggest that the Fr. II inhibitor(s) is (are) amphipathic. The interaction of platelets with PAF and their interaction with the inhibitor(s) are mutually exclusive, and the inhibition may be competitive. 相似文献
15.
Cytokines increase transporter in antigen processing-1 expression more rapidly than HLA class I expression in endothelial cells. 总被引:5,自引:0,他引:5
D E Epperson D Arnold T Spies P Cresswell J S Pober D R Johnson 《Journal of immunology (Baltimore, Md. : 1950)》1992,149(10):3297-3301
Transporter in Ag processing-1 (TAP-1, previously called PSF-1 or Ring-4) is an MHC-encoded gene product that is required for efficient association of intracellular peptide Ag with nascent HLA class I H chain and beta 2-microglobulin, thereby permitting assembly and normal surface expression of the class I molecules. TAP-1 is thought to function as a component of a transmembrane pump, that transports cytoplasmically-derived peptides into the lumen of the endoplasmic reticulum where class I molecules assemble. Synthesis and expression of HLA class I molecules is increased in human endothelial cells by IFN-beta, IFN-gamma, and TNF. We report these same cytokines increase TAP-1 expression. As with class I, TAP-1 is also synergistically increased by combinations of TNF with IFN. Interestingly, cytokine-induced increases in TAP-1 mRNA are markedly more rapid than increases in class I mRNA. This rapid increase in TAP-1 mRNA is reflected in a rapid increase in TAP-1 protein. These results demonstrate that TAP-1 synthesis and class I synthesis are regulated in parallel. The rapidity of the cytokine response of TAP-1 compared to class I further suggests that the constitutive level of TAP-1 expression in endothelial cells is not sufficient to support inducible increases in class I expression. 相似文献
16.
Males’ underreporting of psychological issues, physical symptoms, and personal information is commonplace both in medical and psychological settings in North America. One explanation for this occurrence is men that endorse traditional forms of masculine gender roles underreport or mask their symptoms to avoid being perceived as less masculine. In a similar way, the thesis of the current study was males may also mask and underreport the strength of attachment to their animal companions due to masculinity concerns. These males may also have more difficulty explaining why the bond is of importance. To address these notions, we developed the Human–Animal Interaction Conflicts scale (HAIC) consisting of two psychometrically sound subscales that measure conflicts male owners may have related to their pets. The first subscale involves limiting affection conflict (LAC), which measures underreporting or masking affectionate behavior around animal companions. The second entails conflict explaining the importance of the bond (EBC), which results in males not providing clear or accurate remarks when attempting to describe the bond’s significance. The results from linear regressions analyses support the hypothesis that males endorsing traditional forms of masculine gender (as measured by the Precarious Masculinity Scale) underreport or mask their affectionate behaviors toward animal companions. Similarly, these same men also report more difficulty placing into words the bond they have with their dogs. The current study not only has implications for mental health and medical providers but may also help explain past research where males self-report lower levels of attachment to dogs. 相似文献
17.
Frans Plank 《Morphology》2012,22(2):277-292
Co-occurrence restrictions among affixes are preferably accounted for through general structural constraints, to do with separations of word-internal domains, with hierarchical rankings of the affixes involved, with processing complexity, or with word-prosodic patterns. Disallowing particular designated affixes to combine with one another by (language-particular) stipulation is considered a theoretical option only to be taken as a last resort. Against this backdrop it is argued here that in the much-discussed German case of diminutive-pejorative-absolutive suffix -ling the preclusion of further derivational affixation, in particular suffixation with feminine motional -in, is not due to any such general constraint; rather, this must be recognised as an instance of an affix-specific selectional restriction of a morphosemantic kind. The chief theoretical interest of this particular case is diachronic. While inner suffix -ling, originally a semantically neutral nominalising suffix, was able to acquire a diminutive, pejorative, absolutive-aligned (??passive??) semantics, its original gender remained masculine rather than changing to neuter, as would be semantically more suitable. Thus, with the outer, feminine-deriving suffix -in being sensitive to the gender of its nominal bases, nouns which are formally masculine, as required by -in suffixation, but on semantic grounds ought to be neuter are infelicitous. 相似文献
18.
K Ohnishi 《Origins of life》1984,14(1-4):707-715
Domain structures of class I and class II MHC products were analyzed from a viewpoint of amino acid and nucleotide sequence homologies. Alignment statistics revealed that class I (transplantation) antigen H chains consist of four mutually homologous domains, and that class II (HLA-DR) antigen beta and alpha chains are both composed of three mutually homologous ones. The N-terminal three and two domains of class I and class II (both beta and alpha) gene products, respectively, all of which being approximately 90 residues long, were concluded to be homologous to beta2-microglobulin (beta2M). The membrane-embedded C-terminal shorter domains of these MHC products were also found to be homologous to one another and to the third domain of class I H chains. Class I H chains were found to be more closely related to class II alpha chains than to class II beta chains. Based on these findings, an exon duplication history from a common ancestral gene encoding a beta2M-like primodial protein of one-domain-length up to the contemporary MHC products was proposed. 相似文献
19.
Mariella Espinoza-Herold 《Anthropology & education quarterly》2007,38(3):260-277
This mother—daughter case study focuses on a key feature of discourse within a Mexican immigrant family that links oral traditions to resilience and motivation. I combine observations from a previous ethnographic study with recent follow-up interviews of a Mexican immigrant student building on a funds of knowledge framework and an ecological perspective. Expanding on current mother—daughter pedagogic theory, I map "dichos" as they are emblematic of cultural funds of knowledge and how they assume a relationship to resistance and academic attainment for a young Mexican immigrant. The findings challenge the notion that working-class Latino families do not care about the educational fortunes of their youth and lack knowledge and resources to guide their children academically. 相似文献
20.
Bone is highly dynamic and responsive. Bone location, bone type and gender can influence bone responses (positive, negative
or none) and magnitude. Type I diabetes induces bone loss and increased marrow adiposity in the tibia. We tested if this response
exhibits gender and location dependency by examining femur, vertebrae and calvaria of male and female, control and diabetic
BALB/c mice. Non-diabetic male mice exhibited larger body, muscle, and fat mass, and increased femur BMD compared to female
mice, while vertebrae and calvarial bone parameters did not exhibit gender differences. Streptozotocin-induced diabetes caused
a reduction in BMD at all sites examined irrespective of gender. Increased marrow adiposity was evident in diabetic femurs
and calvaria (endochondrial and intramembranous formed bones, respectively), but not in vertebrae. Leptin-deficient mice also
exhibit location dependent bone responses and we found that serum leptin levels were significantly lower in diabetic compared
to control mice. However, in contrast to leptin-deficient mice, the vertebrae of T1-diabetic mice exhibit bone loss, not gain.
Taken together, our findings indicate that TI-diabetic bone loss in mice is not gender, bone location or bone type dependent,
while increased marrow adiposity is location dependent. 相似文献