The evolution of resistance through costly acquired immunity

We examine the evolutionary dynamics of resistance to parasites through acquired immunity. Resistance can be achieved through the innate mechanisms of avoidance of infection and reduced pathogenicity once infected, through recovery from infection and through remaining immune to infection: acquired immunity. We assume that each of these mechanisms is costly to the host and find that the evolutionary dynamics of innate immunity in hosts that also have acquired immunity are quantitatively the same as in hosts that possess only innate immunity. However, compared with resistance through avoidance or recovery, there is less likely to be polymorphism in the length of acquired immunity within populations. Long-lived organisms that can recover at intermediate rates faced with fast-transmitting pathogens that cause intermediate pathogenicity (mortality of infected individuals) are most likely to evolve long-lived acquired immunity. Our work emphasizes that because whether or not acquired immunity is beneficial depends on the characteristics of the disease, organisms may be selected to only develop acquired immunity to some of the diseases that they encounter

Disempowerment and resistance in the print industry? Reactions to surveillance-capable technology

This article offers a critique of recent characterisations of the effects of electronic technologies in the workplace. It presents detailed case study evidence that calls into question a number of common theoretical assumptions about the character of surveillance at work and the responses of employees to it

A comparison of Wortmann airfoil computer-generated lift and drag polars with flight and wind tunnel results

Computations of drag polars for a low-speed Wortmann sailplane airfoil are compared with both wind tunnel and flight test results. Excellent correlation was shown to exist between computations and flight results except when separated flow regimes were encountered. Smoothness of the input coordinates to the PROFILE computer program was found to be essential to obtain accurate comparisons of drag polars or transition location to either the flight or wind tunnel flight results

Implementing an Online Dispute Resolution Scheme: Using Domain Name Registration Contracts to Create a Workable Framework

Online businesses have grown tremendously in the past decade. As a larger percentage of the U.S. economy moves onto the Internet, a larger percentage of people doing business online will find themselves disagreeing with each other. How those disputes are resolved presents an ongoing challenge in a world where traditional ordering mechanisms, like geographical boundaries, become increasingly antiquated. As contracts are formed across state and national lines, dispute resolution systems built around spatial locations become ever more unwieldy. The complications and costs of securing a favorable decision from a far-off decisionmaking body make reliance on geographic-based systems exceedingly difficult. Out of this situation, a growing number of alternative dispute resolution ( ADR ) options have emerged. As technology evolves, many of these ADR options include new, electronic dimensions. These so- called online dispute resolution ( ODR ) systems represent a blending of traditional ways of solving conflicts while maintaining the advantages of operating online. By creating problem-solving systems which themselves cross borders, ODR systems represent one of the most promising means of ensuring that problems will be fairly resolved. The rate of adoption of ODR procedures, however, remains relatively slow. Despite the need for such systems, many companies opt to leave the issue to be resolved by customers on a case-by-case basis. As a result, many online customers have little confidence that disputes can be taken to anyone but the company with which the consumer transacted. For some potential customers, the risks of doing business online may remain too great. This Note is intended to advance the debate about ODR adoption by suggesting a new approach. While much has been written about what an ODR system should look like, the question of how any such system would be implemented remains problematic. Rather than looking to create new ODR requirements country by country, this Note suggests the creation of a new requirement for all businesses operating online: that they provide an ODR process for their customers which can fairly address the disputes that arise between them. This new obligation would be enforced by the consumers themselves, thus constituting a new weapon for customers to wield against companies that mistreat them. The obligation would take the form of a requirement in the domain name registration contract. Should a company refuse to comply, a disgruntled customer could initiate a proceeding which would result in the deregistration of the company\u27s domain name. Part II opens with a brief description of how the Internet works and how the registration of domain names provides an opportunity to regulate online behavior. It also gives an overview of the present state of both ADR and ODR options for businesses and of the only currently employed mandatory international ODR system. Part III describes some of the chief benefits that could be realized through greater ODR usage, as well as the problems with many of the current options for expanding that usage. Part IV lays out the proposed system and details how it could be implemented, and Part V addresses the potential problems raised by the adhesive nature of the registration contracts being targeted by this system

Information based clustering

In an age of increasingly large data sets, investigators in many different disciplines have turned to clustering as a tool for data analysis and exploration. Existing clustering methods, however, typically depend on several nontrivial assumptions about the structure of data. Here we reformulate the clustering problem from an information theoretic perspective which avoids many of these assumptions. In particular, our formulation obviates the need for defining a cluster "prototype", does not require an a priori similarity metric, is invariant to changes in the representation of the data, and naturally captures non-linear relations. We apply this approach to different domains and find that it consistently produces clusters that are more coherent than those extracted by existing algorithms. Finally, our approach provides a way of clustering based on collective notions of similarity rather than the traditional pairwise measures.Comment: To appear in Proceedings of the National Academy of Sciences USA, 11 pages, 9 figure

A photon-counting photodiode array detector for far ultraviolet (FUV) astronomy

A compact, stable, single-stage intensified photodiode array detector designed for photon-counting, far ultraviolet astronomy applications employs a saturable, 'C'-type MCP (Galileo S. MCP 25-25) to produce high gain pulses with a narrowly peaked pulse height distribution. The P-20 output phosphor exhibits a very short decay time, due to the high current density of the electron pulses. This intensifier is being coupled to a self-scanning linear photodiode array which has a fiber optic input window which allows direct, rigid mechanical coupling with minimal light loss. The array was scanned at a 250 KHz pixel rate. The detector exhibits more than adequate signal-to-noise ratio for pulse counting and event location

Postcard from James H. Morton to G. W. D. Bowers

Postcard from James H. Morton to G. W. D. Bowers. The handwritten note is dated 23 February 1909. There is a transcript of the correspondence in the item PDF