Ramona Austin, Yale University

Nti Mfumu, Tree of the Chief: The Kongo Staff of Office and Mediation of the Consecrated Chiefs of the Lower Kongo

To study the staffs of the consecrated chiefs of the Kongo people of the Lower Congo is to study the fundamental structure of their belief system. An art history of this instrument of power and authority is linked in form to other types of Kongo sculpture. For example, this relationship is especially salient with the motifs of phemba statuary. These are seated mother and child figures in various poses that are connected with a central Kongo (specifically, Yombe) fertility cult. On the pommel of the Kongo staff, such primary motifs reify the relationship between the living and dead members of the clan and the medium of the chief in that relationship as he operates with the staff as loci of power and agency to effect the affairs of his people. Embedded within its motifs, primary and secondary, is the structure of the Kongo cosmos that carries within its architecture the tenets of Kongo belief.

Also embedded in its primary and secondary motifs (reptilian, human, mammals, marine animals and plants) is a précis of the nature of chiefship and a history of the evolution of chiefship from the founding of the kingdom in the fourteenth century to its fragmentation into small states to powerful chieftaincies from the late seventeenth to the late nineteenth centuries. The last king to claim the title presided over a capitol in ruins representing only the myth of the old kingdom. In this history, mythic and cultural, is an inherent tension between the use of the chief’s power given to him by the ancestors through the vehicle of his consecration for the good of the clan on one hand, and the aggrandizement of his own power on the other. This tension has had great historical consequence for the Kongo people. Suggested by the geographic disposition of motifs from geometric (nearer the seat of the old kingdom, Mbanza Kongo) to figural (Kakongo to the coastal groups), is a continuum from symbols that are a geometric script of metaphysical and political space (related to Tchokwe nsona script as illustrated in the Araldi manuscript of the seventeenth century) to more overtly figural motifs in part influenced by contact with Europeans.

No study of the Kongo staff would be complete without a discussion of its impact on the culture of the African Diaspora in the Americas where the Kongo were numerous and among the most culturally influential ethnic groups. A study of the conjuring cane of African American culture of the United States uncovers a fascinating look at the material/spirtual response of slaves and free blacks to the Enligtenment doctrines of Revolutionary and post-Revolutionary America as these espoused the rights of the individual and the equality of man. In this environment the African American staff retained the Kongo chief staff’s function as instrument of protection, power and authority that blends, in some important examples, Kongo visual themes with those of Masonic emblems linking the Black Caribbean to the North American continent in a triangle of cultural influence that appears to pre-date the Haitian revolution. In time, the staff has become known as an instrument of the conjurer who works its powers of spirit force for the protection or benefit of him or herself, or for a client. In summary, the study of the Kongo staff reveals the diasporic influence of Kongo cultural and artistic traditions from Africa to the Americas and the formation of a unique American culture that cannot be described without the contribution of the Kongo people.

Courtney Marie Bonam, Jennifer Eberhardt, Hilary Burbank Bergsieker; Stanford University

From Cities to Suburbs: The Implications of Racialized Space

Our world is filled with racial cues that influence the manner in which people perceive, think about, feel about, and interact with one another. With the current research, we investigate one racial cue that has received little attention within social psychology—physical space. In a series of four studies, we examine (a) the existence of race-space associations, as well as the extent to which exposure to images of spaces associated with Black Americans (e.g., inner cities) increases: (b) detection of Black faces, (c) activation of Black stereotypes, and (d) implicit anti-Black bias. Data collected thus far indicate that both Black and White Americans are associated with specific physical locations, and that Black spaces are rated more negatively than those with White associations. Additionally, results indicate that priming participants with a set of Black spaces can facilitate the speed at which Black faces, relative to White faces, are recognized as faces. Finally, data suggest that simple exposure to a negative Black space (e.g., inner cities) can activate negative stereotypes regarding Black Americans, as well as increase implicit negative attitudes toward members of this group. These studies are significant because they implicate the physical environment in the triggering and maintenance of racial beliefs and attitudes.

Luz B. Gilbert¹, Lee Chae1, Takao Kasuga1, Jeff Townsend², Louise Glass1John W. Taylor¹,
¹ University of California, Berkeley, ² University of Connecticut
Comparative Genomic Hybridizations: Assessing the Ability to Recover Evolutionary Relationships
Comparative Genomic Hybridization (CGH) using DNA microarrays is becoming a popular method of determining phylogenetic relationships among individuals and even species. Although researchers praise the large-scale genome information output as an advantage of this technology for use in phylogenetic analysis, few have questioned the reliability of CGH to correctly determine evolutionary relationships. With the tools at my disposal for the filamentous fungus Neurospora: a genome sequence, a DNA microarray, and a well supported phylogeny for this genus, I had the ability to rigorously address the utility of CGH for phylogenetic studies using both experimental and simulated data.

New kinds of state-initiated associations in much of democratizing Latin America call for decentralization and greater civic participation in governance. These developments appear to grant civic groups participation in policy-making domains. In developing countries plagued by corporatist and clientelist power abuse, however, the success of devolution and ‘bottom-up’ policy design is limited. To what degree are these locally focused policy recommendations being romanticized? Do they enhance grassroots level decision-making as significantly as purported by international lending bodies, non-governmental organizations and social movement activists and scholars?

Using the cases of water and health management decentralization in Brazil - two of many early 1990s decentralization plans intended to expand civic authority - this paper challenges the notion that civil society decision-making authority is guaranteed by decentralization. More specifically, I explain why nearly identical decentralizing policy formats result in such different kinds of civic participation. My findings, collected in Brazil over a 12-month period, show that state or elite actors in water management are more open to civic demands; they incorporate civic concerns into policy agendas more readily than their health counterparts. State actors in health councils are less open to civic demands, at least when they contradict state or elite agendas.

With careful qualitative analysis, this variance shows us that significant civic participation in policy-making forums is produced not by decentralization but by the intersection between at least two of the following four variables: a) institutions in which there is not one distinct but rather several, often unclearly defined power-holders, b) actors that are well networked, c) actors that affiliate with more than one sector within the forum under study and d) actors equipped to interact at a new level of governance: that of the inter-regional political unit, such as the river basin. Crucial here are the multiple affiliations of elite actors, a phenomenon that blurs the frequently exaggerated divide between the state and civil society.

Danielle M. Holmes, University of Minnesota

A Prospective Study of Childhood Maltreatment History and its Implications for Unresolved State of Mind in Early Adulthood

Sandra Leal, Washington University Medical School

The Functional Roles of T-Box Genes in Early CNS Development

The Drosophila central nervous system (CNS) represents a central command post mediating the execution of both simple and complex behaviors throughout the lifecycle of the fruit fly. It is comprised of thousands to millions of precisely interconnected and diverse neurons forming a vast neural network. During embryogenesis, the development of this functionally integrated network is dependent upon three processes: neuronal specification, axon pathfinding, and synaptogenesis. Neuronal specification involves the temporal and spatial generation of distinct neuronal subtypes throughout the anterior-posterior and dorsal-ventral axes of the developing embryo. Axon pathfinding involves the subsequent ability of neurons to project their axons towards proximal or distant targets where they establish terminal contacts via synaptogenesis. Our research focuses primarily on understanding neuronal specification and axon pathfinding mechanisms. Related studies in Drosophila and vertebrates have identified a growing number of conserved transcription factors that act in a combinatorial manner to influence the expression of specification and axon guidance genes that classify neuronal subtypes. However, the present number of identified transcription factors that govern neuronal identity in both flies and mammals accounts for only a minor fraction of a large number of diverse neurons. Thus, to broaden the search for conserved genes that establish neuronal diversity, I undertook a genetic screen in Drosophila and identified the T-box transcription factor genes H15 and midline (mid) as new regulators of neuronal specification. H15 and mid share a related mammalian ortholog, the Tbx-20 gene, which has also been shown to regulate neuronal specification in the mouse spinal cord. As with Tbx-20, we have found that H15 and mid are expressed in discrete neuronal populations throughout the embryonic CNS and that they interact genetically with other key regulators of neuronal specification. To elucidate the regulatory role of H15 and mid in mediating axon pathfinding mechanisms, we are tracking the axon projection patterns of all neurons that express H15 and Mid throughout CNS development. From this ongoing effort, we have identified several groups of H15-positive interneurons that extend axons towards the midline of the embryo. Since interneurons typically express biogenic amines, future studies will determine whether H15- and Mid-positive interneurons can be classified into subtypes based upon the complement of neurotransmitters they express. We have also extended our studies to identify extrinsic factors that regulate H15- and mid-dependent neuronal specification. Preliminary evidence suggests that the ligand-activated bone morphogenic protein (BMP) signaling pathway inhibits H15 gene expression within specific neuronal populations. This intriguing observation links the activity of secreted morphogens with finely tuning the expression of H15 during CNS development. We are currently assessing whether the BMP signaling pathway similarly affects mid expression. We predict that decreased levels of H15 and/or Mid may inhibit the expression of cell surface molecules that are essential for regulating axon guidance and target choice. This hypothesis is supported, in part, by the observation that mid mutants exhibit severe deficits in axon branching and navigation behaviors. In conclusion, identifying the mechanisms that guide neuronal specification and axon pathfinding during CNS development is a daunting challenge. However, by characterizing the functional roles of T-box genes during early CNS development, our work will provide basic clues to further decipher these mechanisms.

Lisa M. Lindeman, University of Wisconsin-Madison

Do Emotional Burdens Feel Like Physical Burdens? The Roots of Some Emotions in Embodied Cognition

While some emotions are innate responses to particular sensory perceptions, such as fear upon hearing a loud noise, many emotions result from the conceptual evaluation of life events, such as a bad grade or lost opportunity, according to cognitive theories of emotion. The question remaining is how these conceptual evaluations evoke the sensations and motor impulses that comprise emotional experience. Recent research in the field of embodied cognition offers a clue. According to embodiment, concepts involve the mental simulation of the sensory-motor experiences upon which they are based. For abstract concepts, these sensory-motor simulations are often metaphorical. For example, the concept of communication is rooted in the experience of giving and receiving physical objects. Hence, when people read sentences involving the abstract transfer of information (e.g., "You told Liz a story"), they simulate movements of their hands consistent with the direction of transfer (Glenberg et al., in press). Simulating bodily experiences also produces peripheral physiological effects, as if one is reliving the experience. Consistent with this, reading sentences about communicating ideas also produces motor impulses in the hands. The application of embodiment to cognitive theories of emotion suggests that some emotions are simulations of bodily experiences, such as smothering, falling, physical injury, or cold, that result when a situation is conceptualized metaphorically in terms of that experience. For example, responsibilities and obligations are often conceptualized as physical burdens (e.g., "heavy work load," "the world on your shoulders"). Thus, according to this metaphor simulation model, emotional burdens should feel like physical burdens. To test this hypothesis, the finding that physical burdens make hills look steeper offers a useful tool. We are currently measuring the effects of emotional burdens on slope perception, and we predict that emotional burdens will also make hills look steeper, as if people taking on a responsibility are truly carrying something heavy.

The performances of photovoltaic and photoelectrochemical devices are generally dependent upon the physicochemical nature of the semiconductor electrode interfaces. In this regard, much research has gone towards the understanding and improvement of silicon (Si) interfaces. For photovoltaic devices utilizing Si/metal junctions, the observed barrier heights are known to be strongly limited by the sensitivity towards the preparation route of the Si surface and the extent of metal silicide formation. For Si/liquid junctions, although the observed barrier heights and electron transfer rates are fairly well defined in organic solvents, Si surfaces typically corrode in aqueous solutions, demonstrate poor interfacial characteristics, and are otherwise unsuited for water-based solar cell designs. These and other problems in both Si-junction types serve as major impediments to the advancement of affordable, non-toxic alternative energy technologies. This presentation will demonstrate the viability of controlled chemical functionalization of Si surfaces with alkyl and aryl groups as a means towards addressing the problems with Si/metal and Si/H2O junctions.

Lymarie Maldonado-Báez, The Johns Hopkins University, Biology Department

Endocytic Scaffold Proteins by Clathrin Adaptors: a Requirement for the Progression of Receptor-mediated Endocytosis

Endocytosis comprises the coordinated action of numerous accessory proteins that facilitate and modulate the internalization of specific membrane proteins (cargo). Adaptor proteins are responsible for cargo selection, clathrin assembly and recruitment of other members of the machinery. In our laboratory, we have characterized two putative adaptor proteins from the epsin protein family, the yeast epsins Ent1 and Ent2, which are essential for viability. We have mapped the essential function of the epsins to the epsin N-terminal homology (ENTH) domain; the endocytic function resides in the C-terminus. The ENTH domain is necessary and sufficient for both viability and normal endocytosis in double epsin knockout cells. Thus, deleting the C-terminal part of these proteins, which contains all the characterized endocytic protein interaction motifs, does not impair endocytosis. Based on these observations we hypothesized that other adaptor proteins may redundantly fulfill the endocytic role of the yeast epsins. The yeast Yap1801 and Yap1802 proteins, homologs of mammalian AP180/CALM, share structural and functional similarities with the epsins. To test for possible redundancy between these proteins as cargo adaptors in endocytosis, we created a quadruple deletion mutant lacking the four adaptors and carrying a plasmid encoding the ENT1 ENTH domain (ENTH1) as the only source of epsin. We found that the ENTH1 domain complements quadruple delete cells, as we previously observed in double epsin knockout cells. However, unlike double epsin knockout+ENTH1, quadruple mutants+ENTH1 are not viable at 37°C and defective for endocytosis of the transmembrane receptor Ste3 at 30°C. Re-introducing either of the Yap180 proteins restores endocytosis and viability at 37°C in the quadruple mutant, suggesting that the Yap180 proteins can replace a function of the epsin C-terminus. Quadruple mutants+ENTH1 were rescued when co-transformed with an NPF-containing truncation of Yap1802, but not with a fragment lacking the NPF motifs. Ent1 truncations and single point mutants of the different motifs in Ent1 have further identified the NPF tripeptide motif-containing region as critical for endocytosis and 37°C growth in the absence of the Yap180 proteins. NPF tripeptide motifs bind to EH domain-containing endocytic scaffold proteins, which are essential for the progression and completion of endocytic internalization. Our results suggest that the NPF motif-containing region is the key redundant C-terminal region shared by the yeast epsin and AP180 proteins, and these results are consistent with a critical physiological role for an NPF/EH-domain interaction between an adaptor and a scaffold. This interaction might be critical for the initiation or stabilization of the early endocytic complex, for the regulation of the different activities of the cargo adaptor protein, and/or the progression of the internalization process.

Marion R. Martin, Davida J. Ankeny Brown, Albert S. Chiou, Richard N. Zare, Stanford University

Effects of reagent vibrational excitation on the Cl + CD₄ reaction

The effects of vibrational excitation on the Cl + CD₄ reaction are investigated by preparing three nearly isoenergetic vibrational states: [3000>, [2100>, and [1110>, where [D₁D₂D₃D₄> identifies the number of vibrational quanta in each C-D oscillator. This is a continuation of previous work on the reactions Cl + CD₄/CH₄ [H. A. Bechtel et al., Mol. Phys. 103, 1837 (2005)]. We observe a preference to remove all energy available in the most excited C-D oscillator with a few minor deviations (see figure). Exciting the [3000>, [2100>, or [1110> mode leads to CD₃ products populated primarily in the ground state, in a state with one quantum of stretch excitation, or in a state with two quanta of stretch excitation, respectively.

For recent international development studies associating decentralization with democratization, see Dani Rodrik “Institutions For High-Quality Growth: What They Are And How To Acquire Them,” in National Bureau Of Economic Research Working Paper No. 7540, February 2000; Anwar Shah and Theresa Thompson “Implementing Decentralized Local Governance: A Treacherous Road with Potholes, Detours and Road Closures 1, ” in World Bank Policy Research Working Paper No. 3353, June 2004. p21. Anna Roumani “Community Driven Development in Northeastern Brazil,” in World Bank Working Paper No. 30803, May 2004. See also James Manor, The Political Economy of Democratic Decentralization (Washington, DC: The World Bank, 1999); Jesse C. Ribot, Democratic Decentralization of Natural Resources: Institutionalizing Popular Participation (Washington, DC: World Resources Institute, 2002). Discussions of the above trends also include Judith Tendler’s Good Government in the Tropics (Baltimore: Johns Hopkins University Press, 1997) and Judith Adler Hellman’s, “The Study of New Social Movements and the Question of Autonomy.” in Arturo Escobar and Sonia E. Alvarez (eds.), The Making of Social Movements in Latin America. (Boulder: Westview Press, 1992).