Information Technology

his case study shows how interactive marketing campaigns can be systematically fine-tuned and made more productive through adaptive experimentation. It details the use of adaptive experimentation in a viral marketing campaign at Plaxo, Inc., a company that provides Internet-based updating of personal contact information. The experiences of Plaxo highlight that even for a product that is amenable to viral marketing, growth is not guaranteed.

This case study details the viral marketing campaign of Plaxo, Inc., a company that provides internet-based updating of personal contact information. The experiences of Plaxo highlight that even with an inherently viral product, viral-growth is not guaranteed. It can require substantial management. The case discusses how such management was done at Plaxo by focusing on a simple viral marketing equation, V= N * Cr, where the two key variables are: N = Number of messages sent and Cr = Conversion Rate of a message. Product features that affected this viral equation were identified and improved with experimentation. In short order, these improvements cumulated to push the company past the tipping point. However, the pursuit of aggressive viral growth can have negative side effects. The company employed a carefully crafted feedback loop via internet alert services that tapped into the blog community. This allowed management to better understand negative perceptions of the product and particularly to turn around critics quickly before their impact got out of control.

With the advent internet in the 1990s to the present day facilities of ubiquitous computing, the internet has changed the computing world in a drastic way. It has traveled from the concept of parallel computing to distributed computing to grid computing and recently to cloud computing. Although the idea of cloud computing has been around for quite some time, it is an emerging field of computer science. Cloud computing can be defined as a computing environment where computing needs by one party can be outsourced to another party and when need be arise to use the computing power or resources like database or emails, they can access them via internet. Cloud computing is a recent trend in IT that moves computing and data away from desktop and portable PCs into large data centers. The main advantage of cloud computing is that customers do not have to pay for infrastructure, its installation, required man power to handle such infrastructure and maintenance. In this paper we will discuss what makes all this possible, what is the architectural design of cloud computing and its applications.

Web Services Composition has evolved much interest amongst the researchers in the academic world as well as the industry. With the proliferation of the Internet amongst the masses and the increasing need for making Web Information System components interoperable, research in this field requires new architectural approaches for composing Web Services. One of the goals by adding the Semantic Web in Web Services research is to provide methods and tools to cater for automatic composition of services on the Web. Such dynamic composition of web services can serve applications and users 'anytime and anywhere'. Though various Web Services Composition approaches out there, in most of these approaches, the 'context' in which the web services are offered is ignored to a certain extent. By the term 'context', we mean any information that can be used to characterize the entity. In this paper, we have presented Context Based Web Service Composition approaches and provided a comparative study of them.

Web services technologies are becoming a de facto standard to integrate distributed applications and systems. Developing applications that support web services interfaces will not be enough to provide complete and coordinated business processes. Thus, we need a new approach to compose these web services together in order to form composite web services. Once a Web service is published and deployed, other applications can discover and invoke it. Business domains have requirement for automatically composing web services according to specified business logic which requires an efficient way of selecting web service according to component requirement. In this paper, we present an approach for automatically composing Web Services into composite service by using ontology for semantic description.

Hypoxic conditions in estuaries are one of the major factors responsible for the declines in habitat quality. Previous studies examining effects of hypoxia on crustacea have focused on individual/population-level, physiological or molecular responses but have not considered more than one type of response in the same study. The objective of this study was to examine responses of grass shrimp, Palaemonetes pugio, to moderate (2.5 ppm DO) and severe (1.5 ppm DO) chronic hypoxia at both the molecular and organismal levels. At the molecular level we measured hypoxia-induced alterations in gene expression using custom cDNA macroarrays containing 78 clones from a hypoxiaresponsive suppression subtractive hybridization cDNA library. Grass shrimp exposed to moderate hypoxia show minimal changes in gene expression. The response after short-term (3 d) exposure to severe hypoxia was up-regulation of genes involved in oxygen uptake/transport and energy production, such as hemocyanin and ATP synthases. The major response by day 7 was an increase of transcription of genes in the mitochondrial genome (16S rRNA, cytochrome b, cytochrome c oxidase I and III), and up-regulation of genes encoding proteins involved in iron metabolism. By day 14 a dramatic reversal was seen, with a significant down-regulation of both mitochondrial and Fe-metabolism genes. Validation of the macroarray results with q-PCR showed similar up-or down-regulation at multiple time points for 9 genes. At the organismal level, our studies showed condition factor of grass shrimp exposed to severe chronic hypoxia was lower than normoxic controls during the first 7 days of the experiment, but there were no differences after that time point, or in grass shrimp exposed to moderate hypoxia. Surprisingly, chronic hypoxia appeared to enhance grass shrimp reproduction; females exposed to moderate hypoxia had higher fecundities and a greater percentage produced first, second and third broods than normoxic shrimp. The hypoxic shrimp took longer to produce their first brood than the normoxic controls, although starved larvae from hypoxia-exposed mothers lived longer than normoxic control larvae. Shrimp exposed to severe hypoxia also had higher fecundity than normoxic controls, although embryos from hypoxia-exposed mothers took longer to hatch than normoxic control embryos. The gene expression and reproductive results suggest that expression levels of genes encoding proteins involved in oxygen and electron transport, energy, and iron metabolism may be useful molecular indicators of both short term (b 7 d) and moderate (14 d) exposure to severe hypoxia, and that chronic hypoxia may have population-level impacts on grass shrimp.