Dynamic building envelopes

Chris Leung explains his recent research into deployable external insulation: dynamic facades which use paraffin wax and passive environmental technology to move between open and closed states and allow what has until now often been mutually exclusive – daylight and minimal heat loss

Archival of Poker Flat MST radar data

The Poker Flat MST (mesosphere stratosphere troposphere) radar has operated from early 1979 to 1985. The data recorded during that time resides on some 1100 magnetic tapes. A second set containing only the derived parameters of velocity, width and signal to noise of the primary echo at each height, plus the noise spectra, occupies another 250 tapes. While processing to generate the compressed data set does correct some known errors, no attempt has been made to identify or remove spurious echoes. Because the Poker Flat data set is such a unique and valuable resource, a proposal is made to archive the data in forms more useful for analysis. The archived data set would contain only the parameters for significant echoes with contamination from airplanes, unwanted ionospheric returns, frequently aliased Doppler signals and other sources removed. The archived set should be as good or better than the example shown and may occupy only 25 to 50 tapes

Toward a Legislative Solution to the Growing HIV/AIDS Epidemic in Russia: A Case for Expanded Health Privacy

The Russian Federation faces one of the fastest growing rates of Human Immunodeficiency Virus (“HIV”) infection in the world. In 1995, Russia adopted comprehensive legislation addressing HIV and the disease caused by this virus, Acquired Immune Deficiency Syndrome (“AIDS”). The legislation prohibited discrimination based on HIV infection and provided access to medical care for people living with HIV/AIDS. Having recognized that Injecting Drug Users involved in sex work will likely act as a bridge to the general population, the Russian government has recently taken greater steps to curb transmission. Russia has moved to decriminalize the distribution of hypodermic needles for prevention of infectious diseases and has committed to increasing HIV/AIDS funding. Given the Russian government’s recent dedication of additional funding to combat HIV/AIDS, this Comment seeks to identify potential barriers to HIV/AIDS prevention in existing Russian law. In both testing and treatment, inadequate protection of private health information may discourage individuals from learning their HIV status and seeking treatment. As such, an effective legislative solution to Russia’s growing epidemic must include greater protections for health privacy. Comprehensive health privacy legislation in the United States may provide a framework for enhancing existing health privacy protections for individuals living with HIV/AIDS in Russia. Despite differences between the legal systems of Russia and the United States, Russian law, like American law addressing health privacy, should clarify the statutory right to health privacy, the remedies tied to the violation of that right, and the path to legal redress for the right’s infringemen

Window on the future

This book describes how UrbanBuzz used this risk capital to unlock potential; funding 27 projects over an intense two-year period

Passive autonomic computing with 'heat-motors' and their compounds

The heat-motor is a simple device that converts thermal-to-mechanical energy, individual heat-motors may be considered as inputs to a ‘class of machine’ that can perform simple Boolean logic operands. This research explores some of the properties of this ‘class of machine’ and an application that uses multiple heatmotors. The high mechanical actuation energy that is generated by the heat-motor is inherted by this ‘class of machine’ and suggests the possibilities for an architecture of reconfiguration in response to different external thermal conditions. The possibility of conditional response to the thermal environment is explored through a case-study project

R. C. Lipsey to Jeremiah Gage (10 June 1863)

Describes the atmosphere after the fall of Vicksburg (Miss.); notably that of people considering fleeing the area. Also makes reference to the heavy loses from Company A, the University Greys.https://egrove.olemiss.edu/ciwar_corresp/1459/thumbnail.jp

Cryptic choice of conspecific sperm controlled by the impact of ovarian fluid on sperm swimming behavior

Despite evidence that variation in male–female reproductive compatibility exists in many fertilization systems, identifying mechanisms of cryptic female choice at the gamete level has been a challenge. Here, under risks of genetic incompatibility through hybridization, we show how salmon and trout eggs promote fertilization by conspecific sperm. Using in vitro fertilization experiments that replicate the gametic microenvironment, we find complete interfertility between both species. However, if either species’ ova were presented with equivalent numbers of both sperm types, conspecific sperm gained fertilization precedence. Surprisingly, the species’ identity of the eggs did not explain this cryptic female choice, which instead was primarily controlled by conspecific ovarian fluid, a semiviscous, protein-rich solution that bathes the eggs and is released at spawning. Video analyses revealed that ovarian fluid doubled sperm motile life span and straightened swimming trajectory, behaviors allowing chemoattraction up a concentration gradient. To confirm chemoattraction, cell migration tests through membranes containing pores that approximated to the egg micropyle showed that conspecific ovarian fluid attracted many more spermatozoa through the membrane, compared with heterospecific fluid or water. These combined findings together identify how cryptic female choice can evolve at the gamete level and promote reproductive isolation, mediated by a specific chemoattractive influence of ovarian fluid on sperm swimming behavior

Criticality for the Gehring link problem

In 1974, Gehring posed the problem of minimizing the length of two linked curves separated by unit distance. This constraint can be viewed as a measure of thickness for links, and the ratio of length over thickness as the ropelength. In this paper we refine Gehring's problem to deal with links in a fixed link-homotopy class: we prove ropelength minimizers exist and introduce a theory of ropelength criticality. Our balance criterion is a set of necessary and sufficient conditions for criticality, based on a strengthened, infinite-dimensional version of the Kuhn--Tucker theorem. We use this to prove that every critical link is C^1 with finite total curvature. The balance criterion also allows us to explicitly describe critical configurations (and presumed minimizers) for many links including the Borromean rings. We also exhibit a surprising critical configuration for two clasped ropes: near their tips the curvature is unbounded and a small gap appears between the two components. These examples reveal the depth and richness hidden in Gehring's problem and our natural extension.Comment: This is the version published by Geometry & Topology on 14 November 200