Negotiating optimum distinctiveness: cognitive tendencies toward primordialism among Mapuche youth

In recent years primordialism, as a model for understanding people's essentialist perceptions of ethnic similarity and difference, has returned to social scientific debates with a new degree of respectability and theoretical rigour. This article provides further evidence for why primordialism is prioritized by ethnic minorities as a cognitive mechanism for maintaining group distinctiveness, drawing on data gathered among indigenous youth in Chile. In the absence of traditional cultural tenets such as indigenous language and knowledge among the majority of the sample, criteria for membership are premised on perceived essentialisms of blood and surname. The result of categorizing others under primordial terms, however, is that it facilitates a space in which individual preferences of ethnic expression and distinctiveness can be negotiated. This brings the dichotomization of primordialism and constructionism under further scrutiny, suggesting that they may be compatible in the everyday practices of social life.     

A resynthesis of the primordial and circumstantial approaches to ethnic group solidarity: Towards an explanatory model

Social scientists who have attempted to explain ethnic group solidarity have tended to use either the primordial or the circumstantial approach. The first approach accounts for strong ethnic attachments on the basis of their ineffable affective significance. Moreover, this affective significance most often surrounds images of the group's distinctive past, thus giving a historical dimension to the concept of primordialism. The second approach views ethnic group solidarity as resulting from certain social circumstances, both internal and external, under which the members of the group exist. It is argued that neither approach alone offers a sufficient explanation ‐ i.e., that the primordial approach cannot readily account for fluctuating ethnic group solidarity and that the circumstantial approach tends to ignore the affective significance of ethnic ties ‐ and that previous attempts to synthesize them have been inadequate as explanatory models. Such a synthetic model is offered, which is based on the oppositional approach originated by Edward Spicer and which maintains that fluctuating ethnicity, along with fluctuating primordial sentiments, can be best explained on the basis of the circumstance of fluctuating opposition.     

Reconsidering primordialism: an alternative approach to the study of ethnicity

This theoretical article first clarifies the exclusive assumptions of primordialism and constructivism. Subsequently, it demonstrates that primordialism has substantial power to explain ethnic phenomena, since (a) ethnic identities persist even in the hardest cases, such as sub-Saharan Africa and the United States, and (b) the attributed significance of assumed kinship has psychological and sociological bases. Finally, this article formulates hypotheses based on the core primordialist assumptions and develops ethnic distance as an explanatory variable on the level of integration of immigrants. It defines ethnic distance as the degree to which two ethnic identities have been solidified as opposed to each other by their dyadic violent conflicts and religious and/or nationalistic education and hypothesizes that the higher the ethnic distance between immigrants and the host society the lower the level of integration.     

C. elegans PAT-6/actopaxin plays a critical role in the assembly of integrin adhesion complexes in vivo

BACKGROUND: The novel focal adhesion protein actopaxin includes tandem unconventional calponin homology (CH) domains and a less well-conserved N-terminal stretch. Dominant-negative studies have implicated actopaxin in focal adhesion formation. RESULTS: PAT-6/actopaxin, the sole actopaxin homolog in C. elegans, is located in body wall muscle attachments that are in vivo homologs of focal adhesions. We show using pat-6 protein null alleles that PAT-6/actopaxin has critical nonredundant roles during attachment maturation. It is required to recruit UNC-89 and myofilaments to newly forming attachments, and also to reposition the attachments so that they form the highly ordered array of dense body and M line attachments that are characteristic of mature muscle cells. PAT-6/actopaxin is not required for the deposition of UNC-52/perlecan in the basal lamina, nor for the initiation of attachment assembly, including the clustering of integrin into foci and the recruitment of attachment proteins PAT-4/ILK, UNC-112, and DEB-1/vinculin from the cytosol. PAT-6/actopaxin, PAT-4/ILK, and UNC-112 are each required for the same steps during attachment assembly in vivo, consistent with the notion that they work together in multiprotein complex. Supporting this idea, PAT-4/ILK can simultaneously bind to PAT-6/actopaxin and UNC-112, forming a ternary complex, in yeast three-hybrid assays. Finally, we show that both calponin homology domains are required for PAT-6/actopaxin's critical functions during attachment assembly in vivo. CONCLUSIONS: We show directly by loss-of-function genetics that PAT-6/actopaxin plays essential roles during the maturation of integrin-mediated muscle attachments in vivo.     

Evidence from surface microscopy for recognition of fleshy and tendinous muscle insertion in extant vertebrate femora: implications for muscle reconstruction in fossils

Recognition of muscle attachment sites and their modification has been an important tool in anthropologic and paleontologic research, but has been compromised by limited ability to recognise sites of tendinous attachments. We investigated bone–tendon (three sites) and bone–muscle (six sites) interfaces in six pairs of femora across a broad taxonomic spectrum of higher amniote archosaurs (both recent and fossil) by epi-illumination microscopy. Direct fleshy and indirect tendinous muscle attachments were identified by dissection of fresh specimens and examination of fossils and the surface microscopic changes identified at those locations. Examination revealed bone modifications specific to each type of muscle insertion, allowing them to be identified and distinguished. Application of a surface microscopy technique not only permits more confident localisation of tendinous attachments, but for the first time allows recognition of sites of direct fleshy muscle attachments – in a reproducible manner across phylogenetic lines.     

The Association of Ethnic Minority Density with Late Entry into Antenatal Care in the Netherlands

In the Netherlands, non-Western ethnic minority women make their first antenatal visit later than native Dutch women. Timely entry into antenatal care is important as it provides the opportunity for prenatal screening and the detection of risk factors for adverse pregnancy outcomes. In this study we explored whether women''s timely entry is influenced by their neighborhood. Moreover, we assessed whether ethnic minority density (the proportion of ethnic minorities in a neighborhood) influences Western and non-Western ethnic minority women''s chances of timely entry into care differently. We hypothesized that ethnic minority density has a protective effect against non-Western women''s late entry into care. Data on time of entry into care and other individual-level characteristics were obtained from the Netherlands Perinatal Registry (2000-2008; 97% of all pregnancies). We derived neighborhood-level data from three other national databases. We included 1,137,741 pregnancies of women who started care under supervision of a community midwife in 3422 neighborhoods. Multi-level logistic regression was used to assess the associations of individual and neighborhood-level determinants with entry into antenatal care before and after 14 weeks of gestation. We found that neighborhood characteristics influence timely entry above and beyond individual characteristics. Ethnic minority density was associated with a higher risk of late entry into antenatal care. However, our analysis showed that for non-Western women, living in high ethnic minority density areas is less detrimental to their risk of late entry than for Western women. This means that a higher proportion of ethnic minority residents has a protective effect on non-Western women''s chances of timely entry into care. Our results suggest that strategies to improve timely entry into care could seek to create change at the neighborhood level in order to target individuals likely of entering care too late.     

The genetic population structure of northern Sweden and its implications for mapping genetic diseases

The northern Swedish population has a history of admixture of three ethnic groups and a dramatic population growth from a relatively small founder population. This has resulted in founder effects that together with unique resources for genealogical analyses provide excellent conditions for genetic mapping of monogenic diseases. Several recent examples of successful mapping of genetic factors underlying susceptibility to complex diseases have suggested that the population of northern Sweden may also be an important tool for efficient mapping of more complex phenotypes. A potential factor contributing to these effects may be population sub-isolates within the large river valleys, constituting a central geographic characteristic of this region. We here provide evidence that marriage patterns as well as the distribution of gene frequencies in a set of marker loci are compatible with this notion. The possible implications of this population structure on linkage- and association based strategies for identifying genes contributing risk to complex diseases are discussed.     

The developmental origins of mammalian oocyte polarity

Drosophila has been an excellent model system to study the cell and molecular determinants of oocyte axis specification, a problem which is little known in mammalian species. Recent evidence supports the notion that mammalian oocytes utilize axis-orienting properties during the course of oogenesis. Among these, axis specification in relation to the oocyte cortex, germinal vesicle (GV) position, anchoring of GV and spindle, and patterning of follicle cell/oocyte attachments are proposed as conserved features of oogenesis in mammals that may be important to the survival and development of the preimplantation embryo.     

The I1307K APC polymorphism: prevalence in non-Ashkenazi Jews and evidence for a founder effect

A missense mutation within the APC gene, I1307K, was described in Ashkenazi individuals at risk for colorectal cancer (CRC) and in the general population. The anecdotal reporting of the occurrence of this mutation in some non-Ashkenazi individuals led us to hypothesize that within the Jewish people, the I1307K polymorphism may reflect a founder mutation, and that the mutation is not restricted to ethnic Ashkenazis. To test that notion, and to establish the occurrence rate of the I1307K polymorphism in non-Ashkenazi Jewish populations, we screened Iraqi and Moroccan Jews and consecutive Jewish CRC patients and performed haplotype analysis with APC-linked markers in two I1307K carrier families. We analyzed Jewish individuals: 210 Moroccans, 160 Iraqis, 148 Ashkenazi, and 349 CRC patients (227 Ashkenazi and 122 non-Ashkenazi). The mutation detection scheme included PCR followed by denaturing gradient gel electrophoresis (DGGE) or modified restriction analysis (MRA). Haplotypes were assessed using three intragenic and three flanking markers. The I1307K polymorphism was detected in 29/227 Ashkenazi (12.8%), 2/122 (1.6%) non-Ashkenazi CRC patients, and in 2 individuals each (approximately 1%) within the Moroccan and Iraqi populations. Allelic pattern analysis in all our I1307K carriers, revealed a common haplotype for the three intragenic markers tested, in all mutation carriers, regardless of ethnic origin. The I1307K polymorphism, therefore, exists in all ethnic Jewish populations: Ashkenazi and non-Ashkenazi, with or without colon cancer. Jewish I1307K mutation carriers share a common allelic pattern with APC-linked markers. This strongly supports the notion of a founder mutation for I1307K.     

The organization of time in biological systems

A notion of organization of time similar to the notion of organization of space in architecture has been introduced. The level and pattern of organization of time in biological systems differs from that in physical and chemical systems, which presents an independent problem. Analysis of the problem leads to a new definition of life as a process of renormalization of possibilities described by a Bayes formula. This definition leads to the notion of self-monitoring as a property of every biological system, and of complicated structure of the biological present, including the physical past and physical future. This is naturally followed by determination by far past, and, hence, memory, and determination by future, i.e. preadaptation, surpassing reflection, aim-setting etc. A direct dependence of a number of elements of a complex system on its stability has been demonstrated. The self-monitoring and organization of time can be traced at various levels of biological hierarchy from intracellular to biosphere level.     

Immigrant transit camps ‐ The formation of dependent relations in Israeli society

In this article three approaches to define and explain negative ethnic attitudes are discussed: the anthropology of cultural misunderstanding, the sociology of how differences in group positions are justified ideologically, and the social psychology of maintaining self‐esteem through intergroup differentiation. The‐ aim is to integrate these approaches into an interdisciplinary model. Social identity theory is used as a frame for this integration. The argument developed is that ingroup values are used for intergroup differentiation and evaluation. This leads to the development of stereotypes. Stereotypes reflect misunderstanding, but also anchor social representations of a hierarchy of group positions (ethnic hierarchy). Depending on the ethnic composition of the larger society, majority and minority groups will differ in their ethnic hierarchies. Discrepancies between ethnic hierarchies will lead to ethnic tension. From the perspective developed, a number of hypotheses is derived about how changes in the socio‐economic position of minority groups will affect intergroup evaluations. Hypotheses based on the category differentiation model and the social identity model are specified with respect to the expected changes in stereotypes and intergroup discrimination of the ethnic majority and minority groups.     

The management of otherness beyond the state: integration policies and inclusive citizenship as a government paradigm in the Basque Country

The ethnic identity of second-generation immigrant youth has important implications for their association with, and integration in, receiving countries. This paper deals with the ethnic identity formation of second-generation Turkish immigrant youth in Germany, with particular attention paid to the notion of reactive ethnicity. While much of the literature discusses the ethnic retention of this specific group as unwillingness to integrate, this paper frames their ethnic identity formation as reactive ethnicity, which emerges in reaction to social exclusion. Utilizing a case study of Turkish students of disadvantaged schools, the article illustrates that reactive ethnicity is strongly linked to perceived discrimination and that it acquires characteristics of resistance when the dominant group denigrates and invalidates the immigrants' culture.     

The Role of Chromosome–Nuclear Envelope Attachments in 3D Genome Organization

Chromosomes are intricately folded and packaged in the cell nucleus and interact with the nuclear envelope. This complex nuclear architecture has a profound effect on how the genome works and how the cells function. The main goal of review is to highlight recent studies on the effect of chromosome–nuclear envelope interactions on chromatin folding and function in the nucleus. The data obtained suggest that chromosome–nuclear envelope attachments are important for the organization of nuclear architecture in various organisms. A combination of experimental cell biology methods with computational modeling offers a unique opportunity to explore the fundamental relationships between different aspects of 3D genome organization in greater details. This powerful interdisciplinary approach could reveal how the organization and function of the genome in the nuclear space is affected by the chromosome–nuclear envelope attachments and will enable the development of novel approaches to regulate gene expression.     

Aurora B is enriched at merotelic attachment sites, where it regulates MCAK

Kinetochores often form merotelic attachments, in which a single kinetochore is attached to microtubules from both spindle poles. These attachments can result in improper chromosome segregation and are a significant source of aneuploidy, a hallmark of cancer. Aurora B kinase and the kinesin-13 microtubule depolymerase mitotic-centromere-associated kinesin (MCAK) are required to release improper microtubule attachments. Aurora B regulates MCAK's activity and localization. We set out to understand why MCAK and Aurora B are more abundant at some metaphase-aligned centromeres but are present at low amounts on most others. We found that members of the Aurora B complex are specifically enriched at merotelic attachment sites. We also found that Aurora B does not require its activity to become enriched at these sites; however, inhibition of Aurora B activity causes a significant increase in the number of merotelic attachments per cell. Aurora B activity enriches MCAK at merotelic attachments and phosphorylates MCAK on residues that regulate its microtubule depolymerase activity. These data demonstrate that proteins that resolve the defect are specifically localized to merotelic attachments, where their enzymatic activities are regulated.     

Multisite phosphorylation of the NDC80 complex gradually tunes its microtubule-binding affinity

Microtubule (MT) attachment to kinetochores is vitally important for cell division, but how these interactions are controlled by phosphorylation is not well known. We used quantitative approaches in vitro combined with molecular dynamics simulations to examine phosphoregulation of the NDC80 complex, a core kinetochore component. We show that the outputs from multiple phosphorylation events on the unstructured tail of its Hec1 subunit are additively integrated to elicit gradual tuning of NDC80-MT binding both in vitro and in silico. Conformational plasticity of the Hec1 tail enables it to serve as a phosphorylation-controlled rheostat, providing a new paradigm for regulating the affinity of MT binders. We also show that cooperativity of NDC80 interactions is weak and is unaffected by NDC80 phosphorylation. This in vitro finding strongly supports our model that independent molecular binding events to MTs by individual NDC80 complexes, rather than their structured oligomers, regulate the dynamics and stability of kinetochore-MT attachments in dividing cells.     

Social rationality and scales of action: inter-ethnic relations in cockfighting and game-fishing,Raiatea, French Polynesia

This article challenges the notion of economic rationality as a criterion for explaining ethnic boundary maintenance. It offers an ethnographic analysis of inter-ethnic relations in the context of games (cockfights and game-fishing contests) in the island of Raiatea (French Polynesia). Although all players engage in the same basic gambling practices, money is differentially scaled and mobilized by the Tahitian and Chinese participants. Building on recent pragmatic approaches to rationality, it is shown that the players' rationalities differ not from the point of view of economic maximization, but only in so far as they participate in social relations at different scales.     

The human spindle assembly checkpoint protein Bub3 is required for the establishment of efficient kinetochore-microtubule attachments

The spindle assembly checkpoint monitors the status of kinetochore-microtubule (K-MT) attachments and delays anaphase onset until full metaphase alignment is achieved. Recently, the role of spindle assembly checkpoint proteins was expanded with the discovery that BubR1 and Bub1 are implicated in the regulation of K-MT attachments. One unsolved question is whether Bub3, known to form cell cycle constitutive complexes with both BubR1 and Bub1, is also required for proper chromosome-to-spindle attachments. Using RNA interference and high-resolution microscopy, we analyzed K-MT interactions in Bub3-depleted cells and compared them to those in Bub1- or BubR1-depleted cells. We found that Bub3 is essential for the establishment of correct K-MT attachments. In contrast to BubR1 depletion, which severely compromises chromosome attachment and alignment, we found Bub3 and Bub1 depletions to produce defective K-MT attachments that, however, still account for significant chromosome congression. After Aurora B inhibition, alignment defects become severer in Bub3- and Bub1-depleted cells, while partially rescued in BubR1-depleted cells, suggesting that Bub3 and Bub1 depletions perturb K-MT attachments distinctly from BubR1. Interestingly, misaligned chromosomes in Bub3- and Bub1-depleted cells were found to be predominantly bound in a side-on configuration. We propose that Bub3 promotes the formation of stable end-on bipolar attachments.     

The Composition,Functions, and Regulation of the Budding Yeast Kinetochore

The propagation of all organisms depends on the accurate and orderly segregation of chromosomes in mitosis and meiosis. Budding yeast has long served as an outstanding model organism to identify the components and underlying mechanisms that regulate chromosome segregation. This review focuses on the kinetochore, the macromolecular protein complex that assembles on centromeric chromatin and maintains persistent load-bearing attachments to the dynamic tips of spindle microtubules. The kinetochore also serves as a regulatory hub for the spindle checkpoint, ensuring that cell cycle progression is coupled to the achievement of proper microtubule–kinetochore attachments. Progress in understanding the composition and overall architecture of the kinetochore, as well as its properties in making and regulating microtubule attachments and the spindle checkpoint, is discussed.