Household composition and housing expenditures in rental-occupied and owner-occupied markets

This article examines the relationship between household compositions and housing expenditures in rental-occupied and owner-occupied markets. The author finds that renters allocate their budget proportionately between housing and nonhousing goods for an additional household member, leaving the budget share of housing expenditures unchanged. For homeowners, nevertheless, an extra member implies a reduction in housing expenditures as a share of total budget. Although age and gender compositions turn out to be significant in determining the budget share of housing expenditures for renters, they play no major role for homeowners. And although an increase in the number of working members for renters significantly reduces the share of budget spent on housing, it has no significant impact for their owner counterparts. Moreover, keeping total expenditures constant, the main income source of the head of the household does not make any difference in terms of resource allocation across housing and nonhousing goods for both renters and owners.

A distributed active defense system against DDoS attacks

This thesis proposes a novel architecture of Distributed Active Defense System (DADS) against Distibuted Denial of Service (DDoS) attacks. Three sub-systems of DADS were built. For each sub-system corresponding algorithms were developed, prototypes implemented, criteria for evaluation were set up and experiments in both simulation and real network laboratory environments were carried out.

Viral RNA silencing suppressors (RSS) : novel strategy of viruses to ablate the host RNA interference (RNAi) defense system

Pathogenic viruses have developed a molecular defense arsenal for their survival by counteracting the host anti-viral system known as RNA interference (RNAi). Cellular RNAi, in addition to regulating gene expression through microRNAs, also serves as a barrier against invasive foreign nucleic acids. RNAi is conserved across the biological species, including plants, animals and invertebrates. Viruses in turn, have evolved mechanisms that can counteract this anti-viral defense of the host. Recent studies of mammalian viruses exhibiting RNA silencing suppressor (RSS) activity have further advanced our understanding of RNAi in terms of host–virus interactions. Viral proteins and non-coding viral RNAs can inhibit the RNAi (miRNA/siRNA) pathway through different mechanisms. Mammalian viruses having dsRNA-binding regions and GW/WG motifs appear to have a high chance of conferring RSS activity. Although, RSSs of plant and invertebrate viruses have been well characterized, mammalian viral RSSs still need in-depth investigations to present the concrete evidences supporting their RNAi ablation characteristics. The information presented in this review together with any perspective research should help to predict and identify the RSS activity-endowed new viral proteins that could be the potential targets for designing novel anti-viral therapeutics.

A survey on latest botnet attack and defense

A botnet is a group of compromised computers, which are remotely controlled by hackers to launch various network attacks, such as DDoS attack and information phishing. Botnet has become a popular and productive tool behind many cyber attacks. Recently, the owners of some botnets, such as storm worm, torpig and conflicker, are employing fluxing techniques to evade detection. Therefore, the understanding of their fluxing tricks is critical to the success of defending from botnet attacks. Motivated by this, we survey the latest botnet attacks and defenses in this paper. We begin with introducing the principles of fast fluxing (FF) and domain fluxing (DF), and explain how these techniques were employed by botnet owners to fly under the radar. Furthermore, we investigate the state-of-art research on fluxing detection. We also compare and evaluate those fluxing detection methods by multiple criteria. Finally, we discuss future directions on fighting against botnet based attacks.

Locating defense positions for thwarting the propagation of topological worms

A common view for the preferable positions of thwarting worm propagation is at the highly connected nodes. However, in certain conditions, such as when some popular users (highly connected nodes in the network) have more vigilance on the malicious codes, this may not always be the truth. In this letter, we propose a measure of betweenness and closeness to locate the most suitable positions for slowing down the worm propagation. This work provides practical values to the defense of topological worms.

CBF : A packet filtering method for DDoS attack defense in cloud environment

Distributed Denial-of-Service attack (DDoS) is a major threat for cloud environment. Traditional defending approaches cannot be easily applied in cloud security due to their relatively low efficiency, large storage, to name a few. In view of this challenge, a Confidence-Based Filtering method, named CBF, is investigated for cloud computing environment, in this paper. Concretely speaking, the method is deployed by two periods, i.e., non-attack period and attack period. More specially, legitimate packets are collected at non-attack period, for extracting attribute pairs to generate a nominal profile. With the nominal profile, the CBF method is promoted by calculating the score of a particular packet at attack period, to determine whether to discard it or not. At last, extensive simulations are conducted to evaluate the feasibility of the CBF method. The result shows that CBF has a high scoring speed, a small storage requirement and an acceptable filtering accuracy, making it suitable for real-time filtering in cloud environment.

A nonlinear approach to testing the unit root null hypothesis : an application to international health expenditures

In this article, we examine the unit root null hypothesis for per capita total Health Expenditures (HEs), per capita private HEs and per capita public HEs for 29 Organization for Economic Co-operation and Development (OECD) countries. The novelty of our work is that we use a new nonlinear unit root test that allows for one structural break in the data series. We find that for around 45% of the countries, we are able to reject the unit root hypothesis for each of the three HE series. Moreover, using Monte Carlo simulations, we show that our proposed unit root model has better size and power properties than the widely used Augmented Dickey–Fuller (ADF) and Lagrange Multiplier (LM) type tests.

Modeling and defense against propagation of worms in networks

Worms are widely believed to be one of the most serious challenges in network security research. In order to prevent worms from propagating, we present a microcosmic model, which can benefit the security industry by allowing them to save significant money in the deployment of their security patching schemes.

Keynote : Detection of and defense against distributed denial-of-service (DDoS) attacks

Distributed denial-of-service (DDoS) attacks typically exhaust bandwidth, processing capacity, or memory of a targeted machine, service or network. Despite enormous efforts in combating DDoS attacks in the past decade, DDoS attacks are still a serious threat to the security of cyberspace. In this talk I shall outline the recent efforts of my research group in detection of and defence against DDoS attacks. In particular, this talk will concentrate on the following three critical issues related to DDoS attacks: (1) Traceback of DDoS attacks; (2) Detection of low-rate DDoS attacks; and (3) Discriminating DDoS attacks from flash crowds.

The contribution of job and partner satisfaction to the homeostatic defense of subjective wellbeing

Two studies investigate subjective wellbeing (SWB) homeostasis. The first investigates the contribution of job satisfaction (JS) and partner satisfaction (PS) to the homeostatic defense of SWB. The extant model of homeostasis does not include either variable. The second study investigates the relationship between Homeostatically Protected Mood (HPMood) and other factors involved in the homeostatic model. It has been proposed that HPMood is the basic, biologically determined, positive mood that saturates SWB and other related variables, and forms the basis of the SWB set-point. Thus, if HPMood is an individual difference and it perfuses other homeostatic variables, then HPMood should be responsible for much of the shared variance between such variables. Two comparative samples are involved. One is a group of 171 Hong Kong Chinese recruited through convenience sampling. The other is a group of 343 Australians recruited via a general population survey. Results indicate that both JS and PS predict significant variance in Global Life Satisfaction beyond the existing factors in the homeostatic model. It is also found that, after controlling for the effect of HPMood, the strength of correlations between SWB and other homeostatic variables is significantly diminished. The implications of these findings are discussed.

Host defense at the ocular surface

Microbial infections of the cornea frequently cause painful, blinding and debilitating disease that is often difficult to treat and may require corneal transplantation. In addition, sterile corneal infiltrates that are associated with contact lens wear cause pain, visual impairment and photophobia. In this article, we review the role of Toll-Like Receptors (TLR) in bacterial keratitis and sterile corneal infiltrates, and describe the role of MD-2 regulation in LPS responsiveness by corneal epithelial cells. We conclude that both live bacteria and bacterial products activate Toll-Like Receptors in the cornea, which leads to chemokine production and neutrophil recruitment to the corneal stroma. While neutrophils are essential for bacterial killing, they also cause tissue damage that results in loss of corneal clarity. These disparate outcomes, therefore, represent a spectrum of disease severity based on this pathway, and further indicate that targeting the TLR pathway is a feasible approach to treating inflammation caused by live bacteria and microbial products. Further, as the P. aeruginosa type III secretion system (T3SS) also plays a critical role in disease pathogenesis by inducing neutrophil apoptosis and facilitating bacterial growth in the cornea, T3SS exotoxins are additional targets for therapy for P. aeruginosa keratitis.

From tax expenditures to rebates: an 'output based equity' approach for Australia's retirement policies

Australia's retirement policies are geared to shifting reliance from the Age Pension to private superannuation, predominately via the use of tax expenditures. This article examines tax expenditures in this area and concludes that inequities and inefficiencies abound. Reform is required. It is argued that the functions of revenue collection and social support should be separated, and the use of tax expenditures in superannuation should be discarded. A rebate system1 or a spending initiative, is proposed. This 'output based equity' approach will address fairness and equity issues at the time of retirement - when full benefits are received.