Model Systems of Human Intestinal Flora, to Set Acceptable Daily Intakes of Antimicrobial Residues

The veterinary use of antimicrobial drugs in food producing animals may result in residues in food, that might modify the consumer gut flora. This review compares three model systems that maintain a complex flora of human origin: (i) human flora associated (HFA) continuous flow cultures in chemostats, (ii) HFA mice, and (iii) human volunteers. The "No Microbial Effect Level" of an antibiotic on human flora, measured in one of these models, is used to set the accept¬able daily intake (ADI) for human consumers. Human volunteers trials are most relevant to set microbio¬log¬ical ADI, and may be considered as the "gold standard". However, human trials are very expensive and unethical. HFA chemostats are controlled systems, but tetracycline ADI calculated from a chemostat study is far above result of a human study. HFA mice studies are less expensive and better controlled than human trials. The tetracycline ADI derived from HFA mice studies is close to the ADI directly obtained in human volunteers

Resistance Monitoring

The problem considered was that of estimating the temperature field in a contaminated region of soil, using measurements of electrical potential and current and also of temperature, at accessible points such as the wells and electrodes and the soil surface. On the timescale considered, essentially days, the equation for the electrical potential is static. At any given time the potential $V$ satisfies the equation $\nabla \cdot (\sigma \nabla V ) = 0$. Time enters the equation only as a parameter since $\sigma$ is temperature and hence time dependent. The problem of finding $\sigma$ when both the potential $V$ and the current density $\sigma \partial{V} / \partial{n}$ are known on the boundary of the domain is a standard inverse problem of long standing. It is known that the problem is ill posed and hence that an accurate numerical solution will be difficult especially when the input data is subject to measurement errors. In this report we examine a possible method for solving the electrical inverse problem which could possibly be used in a time stepping algorithm when the conductivity changes little in each step. Since we are also able to make temperature measurements there is also the possibility of examining an inverse problem for the temperature equation. There seems to be much less literature on this problem, which in our case is essentially, a first order equation with a heat source.(We neglect thermal conductivity, which is small compared with the convection). Combining the results of both inverse problems might give a more robust method of estimating the temperature in the soil

Detection of Insecticide Resistance in Aedes Aegypti to Organophosphate in Pulogadung, East Jakarta

Dengue Hemorrhagic Fever (DHF) is a major public health problem in Indonesia. Jakarta is a capital city with the highest number of dengue patients. Among sporadic endemic areas in Jakarta, Pulogadung, a district of East Jakarta, is one of endemic areas of this disease. The primary strategy for the control of DHF is based on reducing population densities of the main mosquito vector Aedes aegypti. Organophosphate is an insecticide that has been used for more than 25 years in dengue vector control program. The long term used and sublethal dosage of this insecticide can induce resistance. This laboratory study used microplate test and ELISA reader to determine the increase of alfa- esterase activity in Aedes aegypti larvae for detecting the resistance to organophosphate. Resistance pattern of Ae aegypti to organophosphate insecticide in RW 01 Pulogadung was shown to be: 23% high resistant, 33% medium resistant and 44% sensitive. This result was highly related to local community behavior where we found that the use of insecticide spray by the people was very low (8.8% of the sample). We found that the people who used insecticide spray were only 8.8% of the sample. Therefore, organophosphate still can be used in this area to control the Dengue Hemorrhagic Fever in the future. Based on resistance pattern of Ae aegypti to organophosphate insecticide in RW 01 Pulogadung, we can conclude that organophosphate still can be used in this area to control the Dengue Hemorrhagic Fever in the future

Resistance in Superconductors

In this pedagogical review, we discuss how electrical resistance can arise in superconductors. Starting with the idea of the superconducting order parameter as a condensate wave function, we introduce vortices as topological excitations with quantized phase winding, and we show how phase slips occur when vortices cross the sample. Superconductors exhibit non-zero electrical resistance under circumstances where phase slips occur at a finite rate. For one-dimensional superconductors or Josephson junctions, phase slips can occur at isolated points in space-time. Phase slip rates may be controlled by thermal activation over a free-energy barrier, or in some circumstances, at low temperatures, by quantum tunneling through a barrier. We present an overview of several phenomena involving vortices that have direct implications for the electrical resistance of superconductors, including the Berezinskii-Kosterlitz-Thouless transition for vortex-proliferation in thin films, and the effects of vortex pinning in bulk type II superconductors on the non-linear resistivity of these materials in an applied magnetic field. We discuss how quantum fluctuations can cause phase slips and review the non-trivial role of dissipation on such fluctuations. We present a basic picture of the superconductor-to-insulator quantum phase transitions in films, wires, and Josephson junctions. We point out related problems in superfluid helium films and systems of ultra-cold trapped atoms. While our emphasis is on theoretical concepts, we also briefly describe experimental results, and we underline some of the open questions.Comment: Chapter to appear in "Bardeen, Cooper and Schrieffer: 50 Years," edited by Leon N. Cooper and Dmitri Feldman, to be published by World Scientific Pres

Poetry, resistance, world-literature : Adília Lopes and Marie Buck

This essay begins an exploration of how poetry functions within the field of world-literature, drawing specifically on the Warwick Research Collective’s Combined and Uneven Development: Towards a New Theory of World-Literature and reflecting comparatively on the poetry of Adília Lopes and Marie Buck. Even though there are many differences between the two authors and their works, one common feature of their poetics is the deployment of poetry as a form of resistance. As such, both can be seen as especially significant so as to probe into the condition of poetry within a conceptualization of world-literature understood as the literature of the capitalist world-system. As the essay argues, both Adília Lopes and Marie Buck register specific conditions of oppression within a capitalist, patriarchal, society and offer ways to contest them