Blockade of 5-HT2A receptors suppresses hyperthermic but not cardiovascular responses to psychosocial stress in rats

The aim of this study was to determine whether 5-HT2A receptors mediate cardiovascular and thermogenic responses to acute psychological stresses. For this purpose, adult male Wistar hooded rats instrumented for telemetric recordings of either electrocardiogram (ECG) (n=12) or arterial pressure (n=12) were subjected, on different days, to four 15-min episodes of social defeat. Prior to stress, animals received s.c. injection of the selective 5-HT2A receptor antagonist SR-46349B (trans-4-((3Z)3-[(2-dimethylaminoethyl)oxyimino]-3-(2-fluorophenyl)propen-1-yl)-phenol, hemifumarate) (at doses of 0.3, 1.0 and 3.0 mg/kg) or vehicle. The drug had no effect on basal heart rate or heart rate variability indexes, arterial pressure, and core body temperature. Social defeat elicited significant and substantial tachycardic (347±7 to 500±7 bpm), pressor (77±4 to 97±4 mm Hg) and hyperthermic (37.0±0.3 to 38.5±0.1 °C) responses. Blockade of 5-HT2A receptors, at all doses of the antagonist, completely prevented stress-induced hyperthermia. In contrast, stress-induced cardiovascular responses were not affected by the blockade (except small reduction of tachycardia by the highest dose of the drug). We conclude that in rats, 5-HT2A receptors mediate stress-induced hyperthermic responses, but are not involved in the genesis of stress-induced rises in heart rate or arterial pressure, and do not participate in cardiovascular control at rest.

Strain differences in coping behaviour, novelty seeking behaviour, and susceptibility to socially conditioned fear : a comparison between Wistar and Sprague Dawley rats

The aim of the current study was to generate socially conditioned fear in two different strains of rat (Wistar, W and Sprague Dawley, SD) using social conflict, in order to investigate whether the magnitude of the conditioned fear responses in each strain was related to behaviour exhibited prior to or during fear induction (i.e. social conflict). On day one of the study, all intruders were assessed for exploratory activity in a novel environment. Twenty four hours following the novel environment test the locomotor activity of the intruders was assessed, while they underwent a single familiarisation exposure to the arena in which the conflict was subsequently to occur in. Twenty-four hours following familiarisation, intruders underwent either a 10 min social conflict or sham conflict session. One day later we examined the response of the intruders when they were returned to the vacant resident's cage. Upon return to the conflict context, we examined the intruder's ultrasonic distress vocalisations and the extent to which locomotor activity was inhibited. We found that W rats displayed significantly more immobility (i.e. conditioned fear) upon return to context than did SD rats (p < 0.05). Importantly, we observed that the differences in the two strains behaviour upon return to context appeared to be related to their quite different patterns of coping behaviour. The results of the current study indicate that preclinical between-strain comparisons potentially have much to offer in regard to understanding the basis of resilience to social stress.

Victorian Labor and the environment : a legacy to be proud of?

From October 1999 through to November 2010, Victoria was governed by Australian Labor Party (ALP) led governments. The ALP‟s defeat at the November 2010 election provides the opportunity to take stock of their policy achievements in the environmental domain, with a particular focus on how the concept of sustainability was considered in the strategic directions pursued and policy and institutional reforms introduced. In assessing their performance, the context within which the ALP governed is considered, an account of the policy trajectory of their three terms in government provided, and the adequacy of this trajectory assessed. While the analysis is focused on Victoria, the lessons drawn may have wider relevance.

From dictatorship to democracy : simulating the politics of the middle east

 The use of an online diplomatic simulation to increase learning outcomes amongst students of MIddle East Politics. The chapter explores the gains to be had from such collaborative online learning, including the increased depth and breadth of knolwedge gained, the defeat of ethnocentricity, high levels of stduent engagement and the changing role of the teacher in this role play as learners become more self-directed.

The end of the Keating-Howard-Rudd-Gillard era?

Australian political discourse is dominated by ahistorical hyperbole, every election defeat is a landslide, every consecutive electoral loss indicates complete political marginalisation, every poll slump is a crisis, and every struggling leader is the worst ever. Australian Labor is not faring well but we need to distinguish between the ebbs and flows of the political cycle and the fundamentals. Australian politics may be approaching a fundamental break. The political era that began in the early 1990s may be coming to an end and with it Labor's hegemonic position in Australian politics that has endured since Gough Whitlam.

Labor’s century in New South Wales 1911-2011

Examines patterns of support for Labor in New South Wales at a state level from 1911 up until the party's landslide defeat in 2011.

Intervention efficacy among 'At Risk' adolescents: a test of subjective wellbeing homeostasis theory

 This study tests a number of theoretical predictions based on subjective wellbeing (SWB) Homeostasis Theory. This theory proposes that SWB is actively maintained and defended within a narrow, positive range of values around a 'set-point' for each person. Due to homeostatic control, it is predicted to be very difficult to substantially increase SWB in samples operating normally within their set-point-range. However, under conditions of homeostatic defeat, where SWB is lower than normal, successful interventions should be accompanied by a substantial increase as each person's SWB returns to lie within its normal range of values. This study tests these propositions using a sample of 4,243 participants in an Australian Federal Government Program for 'at-risk' adolescents. SWB was measured using the Personal Wellbeing Index and results are converted to a metric ranging from 0 to 100 points. The sample was divided into three sub-groups as 0-50, 51-69, and 70+ points. The theoretical prediction was confirmed. The largest post-intervention increase in SWB was in the 0-50 group and lowest in the 70+ group. However, a small increase in SWB was observed in the normal group, which was significant due to the large sample size. The implications of these findings for governments, schools and policy makers are discussed.

The Psychometric Equivalence of the Personal Wellbeing Index for Normally Functioning and Homeostatically Defeated Australian Adults

Understanding subjective wellbeing (SWB) at the population level has major implications for governments and policy makers concerned with enhancing the life quality of citizens. The Personal Wellbeing Index (PWI) is a measure of SWB with theoretical and empirical credentials. Homeostasis theory offers an explanation for the nature of SWB data, including the distribution of scores, maintenance and change over time. According to this theory, under normal conditions, the dominant constituent of SWB is Homeostatically Protected Mood (HPMood), which is held within a genetically determined range of values around a set-point. However, in extreme circumstances (e.g., financial hardship, chronic illness), HPMood may dissociate from SWB, as cognitive/emotional reactions to the cause of homeostatic challenge assume control over SWB. This study investigates two groups as people scoring in the positive range for SWB and people who are likely to be experiencing homeostatic defeat/challenge. We test whether the reduced influence of HPMood on SWB due to homeostatic defeat has implications for the validity of SWB measurement. Participants were 45,192 adults (52 % female), with a mean age of 48.88 years (SD = 17.35 years), who participated in the first 23 surveys of the Australian Unity Wellbeing Index over the years 2001–2010. Multiple regression analysis, multiple group confirmatory factor analysis, and Rasch modelling techniques were used to evaluate the psychometric performance of the PWI across the two groups. Results show that while the PWI functioned as intended for the normal group, SWB in the challenged group was lower across all PWI domains, more variable, and the domain scores lacked the strength of inter-correlation observed in the normal, comparison group. These changes are consistent with predictions based on homeostasis theory and one major implication of the findings is that SWB measures may not function equivalently across the entire spectrum of possible domain satisfaction scores.

Can we beat DDoS attacks in clouds?

Cloud is becoming a dominant computing platform. Naturally, a question that arises is whether we can beat notorious DDoS attacks in a cloud environment. Researchers have demonstrated that the essential issue of DDoS attack and defense is resource competition between defenders and attackers. A cloud usually possesses profound resources and has full control and dynamic allocation capability of its resources. Therefore, cloud offers us the potential to overcome DDoS attacks. However, individual cloud hosted servers are still vulnerable to DDoS attacks if they still run in the traditional way. In this paper, we propose a dynamic resource allocation strategy to counter DDoS attacks against individual cloud customers. When a DDoS attack occurs, we employ the idle resources of the cloud to clone sufficient intrusion prevention servers for the victim in order to quickly filter out attack packets and guarantee the quality of the service for benign users simultaneously. We establish a mathematical model to approximate the needs of our resource investment based on queueing theory. Through careful system analysis and real-world data set experiments, we conclude that we can defeat DDoS attacks in a cloud environment. © 2013 IEEE.

Defence against code injection attacks

Code injection attacks are considered serious threats to the Internet users. In this type of attack the attacker injects malicious codes in the user programs to change or divert the execution flows. In this paper we explore the contemporary defence strategies against code injection attacks (CIAs) and underline their limitations. To overcome these limitations, we suggest a number of countermeasure mechanisms for protecting from CIAs. Our key idea relies on the multiplexing technique to preserve the exact return code to ensure the integrity of program execution trace of shell code. This technique also maintains a FIFO (first in first out) queue to defeat the conflict state when multiple caller method makes a call simultaneously. Finally, our technique can provide better performance, in terms of protection and speed, in some point compared to the CFI (control flow integrity) as well as CPM (code pointer masking) techniques.

A review of vulnerability and risks for schizophrenia: beyond the two hit hypothesis

Schizophrenia risk has often been conceptualized using a model which requires two hits in order to generate the clinical phenotype-the first as an early priming in a genetically predisposed individual and the second a likely environmental insult. The aim of this paper was to review the literature and reformulate this binary risk-vulnerability model. We sourced the data for this narrative review from the electronic database PUBMED. Our search terms were not limited by language or date of publication. The development of schizophrenia may be driven by genetic vulnerability interacting with multiple vulnerability factors including lowered prenatal vitamin D exposure, viral infections, smoking intelligence quotient, social cognition cannabis use, social defeat, nutrition and childhood trauma. It is likely that these genetic risks, environmental risks and vulnerability factors are cumulative and interactive with each other and with critical periods of neurodevelopmental vulnerability. The development of schizophrenia is likely to be more complex and nuanced than the binary two hit model originally proposed nearly thirty years ago. Risk appears influenced by a more complex process involving genetic risk interfacing with multiple potentially interacting hits and vulnerability factors occurring at key periods of neurodevelopmental activity, which culminate in the expression of disease state. These risks are common across a number of neuropsychiatric and medical disorders, which might inform common preventive and intervention strategies across non-communicable disorders.

The influence of Britain's Margaret Thatcher on Australian politics and Australia's influence on her, 1972-1983

This thesis examines the relationship between leading British conservative politician, Margaret Thatcher and Australia, from her first visit in 1972 to the defeat of the Liberal Party or ‘Conservative’ government led by Malcolm Fraser in the 1983 Australian elections and shows that Australia played a significant role in Thatcher’s career.

Funding the ‘Islamic State’: looting antiquities and the international black market

A key revenue stream for various militant groups across the Middle East, including the Islamic State in Iraq and Syria (ISIS), is the illicit looting and trafficking of antiquities which are sold on the international black market. Various heritage sites are being looted by ISIS and others with devastating efficiency and on an industrial scale. While exact figures are difficult to ascertain, the profits from these looting operations are estimated to be the second largest revenue stream for ISIS after the illegal sale of crude oil. The illicit trafficking of antiquities is therefore financing the devastating advance of ISIS and any effort, including that by the Australian Department of Defence, to defeat ISIS must address this significant issue. More research is urgently needed to understand the precise nature, scope and variety of antiquities looting across the Middle East, the extent to which it is funding groups like ISIS, and to consider Australia’s role in international strategies to stanch this ongoing problem.

Multilayer hybrid strategy for phishing email zero-day filtering

The cyber security threats from phishing emails have been growing buoyed by the capacity of their distributors to fine-tune their trickery and defeat previously known filtering techniques. The detection of novel phishing emails that had not appeared previously, also known as zero-day phishing emails, remains a particular challenge. This paper proposes a multilayer hybrid strategy (MHS) for zero-day filtering of phishing emails that appear during a separate time span by using training data collected previously during another time span. This strategy creates a large ensemble of classifiers and then applies a novel method for pruning the ensemble. The majority of known pruning algorithms belong to the following three categories: ranking based, clustering based, and optimization-based pruning. This paper introduces and investigates a multilayer hybrid pruning. Its application in MHS combines all three approaches in one scheme: ranking, clustering, and optimization. Furthermore, we carry out thorough empirical study of the performance of the MHS for the filtering of phishing emails. Our empirical study compares the performance of MHS strategy with other machine learning classifiers. The results of our empirical study demonstrate that MHS achieved the best outcomes and multilayer hybrid pruning performed better than other pruning techniques.