On Are we all postracial yet?

ABSTRACT

If the postracial is a coherent formation, it is produced not by ideological lock-step but by distributed affinities and relations in a transnational space of interconnection and exchange. The neoliberal erasure of ‘?…?the structural conditions of racial reproduction and racist articulation’ (34) and the clouding of the historicity of racisms produces postraciality as ‘the illusion that the dream of the nonracial has already been realized’ (180). This illusion is familiar in writing on the postracial that focuses on the denial – be it through the averted gaze of ‘color-blindness’, or the official state prohibition of racism, or the triumphalism of strategic declarations of the ‘end of racism’ – of enduring racialized inequality. Goldberg’s advance is to explore how the illusion has become increasingly weaponized; that far from signalling the end of race, it represents an emergent ‘neo-raciality, racism’s extension if not resurrection’ (24).     

‘Are fish what they eat’ all year round?

Isotope turnover in muscle of ectotherms depends primarily on growth rather than on metabolic replacement. Ectotherms, such as fish, have a discontinuous pattern of growth over the year, so the isotopic signature of muscle (δ¹³C and δ¹⁵N) may only reflect food consumed during periods of growth. In contrast, the liver is a regulatory tissue, with a continuous protein turnover. Therefore, the isotopic composition of liver should respond year round to changes in the isotopic signature of food sources. Therefore, we predicted that (1) Whitefish in Lake Geneva would have larger seasonal variation in the isotopic variation of the liver compared to that of the muscle tissue, and (2) the isotope composition of fish muscle would reflect a long-term image of the isotope composition of the food consumed only throughout the growth period. To test these expectations, we compared the isotope compositions of Whitefish muscle, liver and food in a 20-month study. We found that the seasonal amplitude of isotope variation was two to three times higher in liver compared to muscle tissue. During the autumn and winter, when growth was limited, only the isotopic signature of liver responded to changes in the isotope composition of the food sources. The δ¹³C and δ¹⁵N of muscle tissue only reflected the food consumed during the spring and summer growth period.     

Why aren’t we all hutterites?

In this paper I explore the psychology of ritual performance and present a simple graphical model that clarifies several issues in William Irons’s theory of religion as a “hard-to-fake” sign of commitment. Irons posits that religious behaviors or rituals serve as costly signals of an individual’s commitment to a religious group. Increased commitment among members of a religious group may facilitate intra-group cooperation, which is argued to be the primary adaptive benefit of religion. Here I propose a proximate explanation for how individuals are able to pay the short-term costs of ritual performance to achieve the long-term fitness benefits offered by religious groups. The model addresses three significant problems raised by Irons’s theory. First, the model explains why potential free-riders do not join religious groups even when there are significant net benefits that members of religious groups can achieve. Second, the model clarifies how costly a ritual must be to achieve stability and prevent potential free-riders from joining the religious group. Third, the model suggests why religious groups may require adherents to perform private rituals that are not observed by others. Several hypotheses generated from the model are also discussed. Richard Sosis is an assistant professor of anthropology at the University of Connecticut. His research interests include the evolution of cooperation, utopian societies, and the behavioral ecology of religion. In collaboration with Bradley Ruffle (Ben Gurion University) he is currently investigating the impact of privatization and religiosity on intra-group trust within Israeli Kibbutzim.     

Are we there yet? Tracking the development of new model systems

It is increasingly clear that additional 'model' systems are needed to elucidate the genetic and developmental basis of organismal diversity. Whereas model system development previously required enormous investment, recent advances including the decreasing cost of DNA sequencing and the power of reverse genetics to study gene function are greatly facilitating the process. In this review, we consider two aspects of the development of new genetic model systems: first, the types of questions being advanced using these new models; and second, the essential characteristics and molecular tools for new models, depending on the research focus. We hope that researchers will be inspired to explore this array of emerging models and even consider developing new molecular tools for their own favorite organism.     

Are kubo hunters ‘show offs’?

The ‘show off’ hypothesis proposed by K. Hawkes, and tested using data on Ache foragers, makes important connections between food resource choice, reproductive strategies, and food sharing by human foragers. We test predictions derived from that hypothesis concerning contexts of meat acquisition, association between individuals, mobility, and reproductive success among Kubo hunter-horticulturalists of the interior lowlands of Papua New Guinea. Application of the hypothesis to both the Kubo and Ache cases is questioned. Differences between Kubo males in means and variances of returns from hunting arise as a consequence of differential target specialization; they do not map onto variation in reproductive success.     

Are bacterial ‘autotransporters’ really transporters?

Autotransporters are bacterial outer membrane proteins that consist of a large N-terminal extracellular domain ('passenger domain') and a C-terminal beta-barrel domain ('beta domain'). The beta domain was originally proposed to function as a channel that transports its own passenger domain across the outer membrane. Results of recent structural, biochemical and molecular genetic studies, however, have challenged this idea. Here I describe an alternative model in which translocation of the passenger domain is mediated by an exogenous factor (possibly a newly identified factor necessary for assembly of outer membrane proteins called 'Omp85/YaeT'), whereas the beta domain only targets the protein to the outer membrane and serves as a membrane anchor.     

Efficient sample processing for proteomics applications—Are we there yet?

The ability to solubilize and digest protein extracts and recover peptides with high efficiency is of paramount importance in proteomics. A novel proteomic sample preparation protocol by Krijgsveld and colleagues (Hughes et al, 2014) provides significant advantages by enabling all sample processing steps to be carried out in a single tube to minimize sample losses, thereby enhancing sensitivity, throughput, and scalability of proteomics analyses.     

Cryptosporidium virulence determinants--are we there yet?

Exposure to Cryptosporidium parvum in healthy individuals results in transient infection that may be asymptomatic or can result in self-limited diarrhoea. In contrast, acquired immune deficiency syndrome patients with cryptosporidiosis can experience severe manifestations of disease. Volunteer studies have demonstrated that as few as 10 oocysts can cause infection in otherwise healthy adults and that isolates from geographically diverse regions differ in infectivity and, perhaps, virulence. Variability in isolate pathogenicity and infectivity has also been seen in bovine and murine models, respectively. Furthermore, isolate specific differences in protein composition and in host immunoreactivity have been observed. The molecular basis for differences in pathogenicity is not understood. Determining which factors are responsible for host selectivity and for the initiation, establishment, and perpetuation of infection with Cryptosporidium is key to rational drug design and vaccine development. To date, no specific virulence factors have been unequivocally shown to individually cause direct or indirect damage to host tissues nor have mutant strains been produced that could prove that particular deletions result in less virulent strains. Nevertheless, a number of candidate molecules have been identified by immunological and molecular methods. Here, we review the salient characteristics of some of these putative virulence determinants, including molecules that are involved in adhesion, protein degradation and the modulation of the host responses.     

Exploiting the apoptotic process for management of HIV: Are we there yet?

CD4⁺ T cells die in individuals infected with HIV, either as a result of direct HIV infection or as uninfected innocent bystanders. Possible mechanisms for bystander killing include generation of viral products such as Tat or gp120 and expression of death receptor ligands, such as FasL, that engage functional death receptors on uninfected cells. This review covers the sometimes conflicting in vitro and ex vivo studies that address these possible mechanisms of HIV-associated cell death. It is an intriguing possibility that manipulation of cell death processes, to decrease bystander death or increase death of infected cells, in patients infected with HIV might provide a useful adjunct to antiretroviral therapy.     

Insulin producing cells derived from embryonic stem cells: Are we there yet?

Derivation of insulin producing cells (IPCs) from embryonic stem (ES) cells provides a potentially innovative form of treatment for type 1 diabetes. Here, we discuss the current state of the art, unique challenges, and future directions on generating IPCs.     

Are the oldest ‘fossils’, fossils?

A comparative statistical study has been carried out on populations of modern algae, of Precambrian algal microfossils, of the organized elements of the Orgueil carbonaceous meteorite, and of the oldest microfossil-like objects now known (spheroidal bodies from the Fig Tree and Onverwacht Groups of the Swaziland Supergroup, South Africa). The distribution patterns exhibited by the >3000 m.y.-old Swaziland microstructures bear considerable resemblance to those of the abiotic organized elements but rather markedly differ from those exhibited by younger, assuredly biogenic, populations. Based on these comparisons it is concluded that the Swaziland spheroids could be, at least in part, of non-biologic origin; these oldest known fossil-like micro-structures should not be regarded as constituting firm evidence of Archean life.Given at the International Seminar Origin of Life, 2–7 August 1974, Moscow, U.S.S.R.     

Are all fishes ancient polyploids?

Euteleost fishes seem to have more copies of many genes than their tetrapod relatives. Three different mechanisms could explain the origin of these 'extra' fish genes. The duplicates may have been produced during a fish-specific genome duplication event. A second explanation is an increased rate of independent gene duplications in fish. A third possibility is that after gene or genome duplication events in the common ancestor of fish and tetrapods, the latter lost more genes. These three hypotheses have been tested by phylogenetic tree reconstruction. Phylogenetic analyses of sequences from human, mouse, chicken, frog (Xenopus laevis), zebrafish (Danio rerio) and pufferfish (Takifugu rubripes) suggest that ray-finned fishes are likely to have undergone a whole genome duplication event between 200 and 450 million years ago. We also comment here on the evolutionary consequences of this ancient genome duplication.     

Are all MRSA made equal?

The health and economic burden of methicillin-resistant Staphylococcus aureus (MRSA) in the medical realm is considerable. Although there is ample clinical and laboratory evidence indicating that methicillin-susceptible S. aureus (MSSA) is heterogeneous in disease causation, the same heterogeneity has not been well documented for MRSA. Data from animal models and human studies suggest that MRSA is at least as pathogenic as MSSA. Many comparative clinical studies, mainly retrospective, have assessed the virulence of MSSA and MRSA. Whereas the majority of these studies may be deficient in some aspects of clinical design, there has been a definite trend towards implicating MRSA as the more aggressive pathogen. Such an observation, however, must be tempered with the fact that few such studies have attempted to establish clonality among MRSA isolates. Thus, it is conceivable that hypervirulent clones may represent an important proportion of MRSA from hospital studies where patient-patient spread is likely and, accordingly, comparative studies may be biased. Future clinical studies should be prospective and should use well-defined and homogeneous patient groups. As well, for comparison of MRSA and MSSA, an understanding of clonality is essential.