Not Found in Tibetan Society : Culture, Childbirth, and a Politics of Life on the Roof of the World

This article explores the work of culture and politics in the context of health-development interventions. Specifically, I discuss a maternal-child health project that was conceived and executed in the Tibet Autonomous Region, China, and the place of engaged medical anthropology therein. This work takes inspiration from Pigg\u27s (1997) insights about the ways health-development programs can adopt specific interpretive lenses that create categories of being and experience such as Traditional Birth Attendants (TBAs). This article illustrates the ways such categories circulate to serve the needs of governmental and non-governmental organizations, and, in the process, how they run the risk of essentializing culture or eliding the complex realities in which people live. Yet this article also argues that such elision is neither a given nor one-sided. Rather, such programs are enmeshed within a realpolitik in places such as Tibet where the trope of “culture” is both problematic and deeply influential, and where demographics (including maternal and infant mortality statistics) are politicized in particular ways. The article argues that far from being “anti-political,” (Ferguson 1994) such health development efforts are domains in which a “politics of life” (Fassin 2007) inheres. Even so, such efforts can be successful, and can help to nuance and ground the ephemeral yet powerful concepts of structural violence and social suffering

Weak Z-structures for some classes of groups

Motivated by the usefulness of boundaries in the study of hyperbolic and CAT(0) groups, Bestvina introduced a general approach to group boundaries via the notion of a Z-structure on a group G. Several variations on Z-structures have been studied and existence results have been obtained for some very specific classes of groups. However, little is known about the general question of which groups admit any of the various Z-structures, aside from the (easy) fact that any such G must have type F, i.e., G must admit a finite K(G,1). In fact, Bestvina has asked whether every type F group admits a Z-structure or at least a "weak" Z-structure. In this paper we prove some rather general existence theorems for weak Z-structures. Among our results are the following: Theorem A. If G is an extension of a nontrivial type F group by a nontrivial type F group, then G admits a Z-structure. Theorem B. If G admits a finite K(G,1) complex K such that the corresponding G-action on the universal cover contains a non-identity element properly homotopic to the identity, then G admits a weak Z-structure. Theorem C. If G has type F and is simply connected at infinity, then G admits a weak Z-structure.Comment: Significant revisions, including a strengthening of one of the main theorems. 25 pages, 1 figur

Resisting electronic payment systems: burning down the house?

This commentary explains the phenomena of path dependence, hysteresis, and network economies using lively historical and contemporary examples. The author shows how the path dependence and network economies can interact to produce a variety of undesirable ends-inefficient payment systems, the adoption of inferior technology, or disasters like the 1834 fire that destroyed the British House of Lords.Payment systems

Status of direct detector and array development

Programs are now underway to develop and demonstrate the detector/array technology needed for the Space Infrared Telescope Facility (SIRTF), Large Deployable Reflector (LDR), and other future NASA missions. The development goal is to achieve focal plane sensitivities, at extended integration times over the 2 to 700 microns range, limited only by the low astrophysical backgrounds encountered in cryogenic telescopes such as SIRTF. Dramatic progress has been made in the last 2 to 3 years in integrated array and detector systems for low background astronomical applications. With the broadly based developments and lab characterizations now underway for SIRTF and similar space applications, coupled with the rapidly expanding art and science of ground based astronomical imagery with arrays, the potential for effective utilization of arrays with LDR appears to be very good

The Bullet Cluster is not a Cosmological Anomaly

The Bullet Cluster (1E0657-56) merger is of exceptional interest for testing the standard cold-dark-matter plus cosmological constant cosmological model, and for investigating the possible existence of a long- or short-range "fifth-force" in the dark sector and possible need for modifications of general relativity or even of Newtonian gravity. The most recent previous simulations of the Bullet Cluster merger required an initial infall velocity far in excess of what would be expected within the standard cosmological model, at least in the absence of additional forces or modifications to gravity. We have carried out much more detailed simulations, making pixel-by-pixel fits to 2D data-maps of the mass distribution and X-ray emission, allowing for triaxial initial configurations and including MHD and cooling. Here, we compare the initial conditions of the Bullet Cluster merger to those in similar-mass merging clusters in the Horizon cosmological simulation. We conclude that the observed properties of the Bullet Cluster are completely consistent with Lambda-CDM.Comment: 7 pages, 4 figure

Adaptive tracking for complex systems using reduced-order models

Reduced-order models are considered in the context of parameter adaptive controllers for tracking workspace trajectories. A dual-arm manipulation task is used to illustrate the methodology and provide simulation results. A parameter adaptive controller is designed to track the desired position trajectory of a payload using a four-parameter model instead of a full-order, nine-parameter model. Several simulations with different payload-to-arm mass ratios are used to illustrate the capabilities of the reduced-order model in tracking the desired trajectory

Experimental evaluation of candidate graphical microburst alert displays

A piloted flight simulator experiment was conducted to evaluate issues related to the display of microburst alerts on electronic cockpit instrumentation. Issues addressed include display clarity, usefulness of multilevel microburst intensity information, and whether information from multiple sensors should be presented separately or 'fused' into combined alerts. Nine active airline pilots of 'glass cockpit' aircraft participated in the study. Microburst alerts presented on a moving map display were found to be visually clear and useful to pilots. Also, multilevel intensity information coded by colors or patterns was found to be important for decision making purposes. Pilot opinion was mixed on whether to 'fuse' data from multiple sensors, and some resulting design tradeoffs were identified. The positional information included in the graphical alert presentation was found useful by the pilots for planning lateral missed approach maneuvers, but may result in deviations which could interfere with normal airport operations. A number of flight crew training issues were also identified