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INTRUDER DYNAMICS RESPONSE OF GRANULAR MEDIA WITH NON-LINEAR INTERACTION POTENTIALSNewlon, Scott 01 December 2017 (has links)
An investigation into the intruder dynamics of dry dimensionless, frictionless discs in bidispersed, disordered systems is carried out using computer simulations. The velocity of an intruder particle driven under constant force is used as a tool to determine scaling of velocity as a function of packing pressure. Using these velocity for a range of pressures, $4 \times 10^{-7}\leq P \leq 4 \times 10^{-2}$. A universal scaling relation is proposed and plotted. The force required to cause the packing to yield to the driven intruder is determined and plotted as function of pressure. Power law exponents were extracted for the yielding force vs. the pressure. The extracted values were used to study the micro-rheology of the intruder particle. Grain scale characteristics are used to infer global elastic modulus properties.
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The Acute Effects of Methamphetamine and 1-Benzylpiperazine on Aggressive Behaviour in Adolescent Male Hooded RatsJohnson, Hamish Neil Leonard January 2010 (has links)
Violent crime and aggressive behaviour are of increasing concern in New Zealand. Much of this is displayed by adolescent males who have an association with some form of substance use, abuse or dependence. This is especially relevant for stimulant drugs, especially methamphetamine (MA), and 1-benzylpiperazine (BZP). Previous research has shown that BZP has similar neurochemical and behavioural effects to MA, and there is a large volume of research showing an association between chronic MA use and aggression. In contrast to this, there has been little research into the consequences of a single administration of MA, which is often portrayed by the media as having the same detrimental effects as chronic use.
The present study was designed to determine whether or not acute MA would induce aggressive behaviour in adolescent male hooded rats. In addition, the study also examined whether BZP had a similar effect to MA. Sixty male hooded rats aged between 41 to 50 postnatal days (PND), were utilised and divided into five groups of 12 rats each: saline; 1mg/kg (low dose) or 2mg/kg (high dose) MA; 10mg/kg (low dose) or 20mg/kg (high dose) BZP. The rats were tested using the resident/intruder test of aggression, consisting of eight measures of aggressive behaviour. The results suggested that, rats treated with either a low or high dose of MA or BZP were significantly less aggressive than saline-treated rats. There appeared to be little to distinguish between the two drugs in their effects on the responses recorded. It was concluded that an acute administration of either MA or BZP did not increase aggression, and thus did not support the view that aggression will result from a single dose of MA (or indeed BZP that has not been previously investigated in this context).
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Security Issues regarding MANET (Mobile Ad Hoc Networks) : Challenges and SolutionsSarwar, Yasir, Ali, Muhammad Arshad January 2011 (has links)
Now a day, it is no longer optional to have security solutions even inevitable for every kind of organizations and individuals. There are number of generic tools which are common for organizations as well as for individual users to provide security which includes; Anti-Spam, Anti-Virus etc., and network security have become essential issue in MANET. Security is one of the main issues in the MANET especially with respect to size and complexity of the network. The aim of the thesis is to discuss different aspects of security in MANET (e.g. multi-layer intrusion detection technique in multi hop network of MANET, security problems relates between multihop network and mobile nodes in MANET etc) and also implement some of the solutions (e.g. comparative study of different routing protocol (AODV, DSR and TORA) security threats within MANET network like intruder behavior, tapping and integrity, MANET link layer and network layer operations with respect to information security etc) with respect to MANET network. This report also discusses different number of scenarios of MANET network which we implement in our simulation. In our simulation we use to implement different routing protocols and also did comparative study that which one is better with respect to different aspects. We also use to implements mechanisms of intruder behavior, tapping and integrity, and MANET link layer and network layer operations with respect to information security.
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A Low-Complexity Algorithm For Intrusion Detection In A PIR-Based Wireless Sensor NetworkSubramanian, Ramanathan 05 1900 (has links) (PDF)
This thesis investigates the problem of detecting an intruder in the presence of clutter in a Passive Infra-Red (PIR) based Wireless Sensor Network (WSN). As one of the major objectives in a WSN is to maximize battery life, data transmission and local computations must be kept to a minimum as they are expensive in terms of energy. But, as intrusion being a rare event and cannot be missed, local computations expend more energy than data transmission. Hence, the need for a low-complexity algorithm for intrusion detection is inevitable.
A low-complexity algorithm for intrusion detection in the presence of clutter arising from wind-blown vegetation, using PIR sensors is presented. The algorithm is based on a combination of Haar Transform (HT) and Support Vector Machine (SVM) based training. The amplitude and frequency of the intruder signature is used to differentiate it from the clutter signal. The HT was preferred to Discrete Fourier Transform (DFT) in computing the spectral signature because of its computational simplicity -just additions and subtractions suffice (scaling coefficients taken care appropriately). Intruder data collected in a laboratory and clutter data collected from various types of vegetation were fed into SVM for training. The optimal decision rule returned by SVM was then used to separate intruder from clutter. Simulation results along with some representative samples in which intrusions were detected and the clutter being rejected by the algorithm is presented.
The implementation of the proposed intruder-detection algorithm in a network setting comprising of 20 sensing nodes is discussed. The field testing performance of the algorithm is then discussed. The limitations of the algorithm is also discussed.
A closed-form analytical expression for the signature generated by a human moving along a straight line in the vicinity of the PIR sensor at constant velocity is provided. It is shown to be a good approximation by showing a close match with the real intruder waveforms. It is then shown how this expression can be exploited to track the intruder from the signatures of three well-positioned sensing nodes.
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Behavioural profiles and cellular mechanisms of retinoid-induced depressionTrent, Simon January 2010 (has links)
Vitamin A and its derivatives, known as retinoids, are involved in a number of functions in the developing and adult brain (Lane et al., 2005). Roaccutane (13-cis-retinoic acid, 13-cis-RA) is a synthetic retinoid used for the treatment of severe cystic acne, although its use has been controversially associated with adverse psychiatric events including depression. In this thesis, the presence of retinoid receptors in the rat hippocampus was verified and a similar profile of expression was observed in the rat raphe nuclei for the first time. The expression of retinoid receptors in brain regions that are implicitly associated with depression pathology provides proof of concept for retinoids to influence depressive behaviour. The ability of 13-cis-RA treatment to induce a pro-depressive profile in animal models of depression-related behaviour was tested. In the resident-intruder paradigm, adult rats treated for 7 or 14 days with 13-cis-RA (1mg/kg, i.p.) showed reduced aggressive behaviour, with a concomitant increase in flight submit and flight escape behaviours, compared with vehicle-treated controls. These findings are indicative of increased depression-related behaviour. However, chronic treatment did not alter depression-related behaviour in the forced swim test and sucrose consumption anhedonia paradigms The molecular mechanisms mediating 13-cis-RA-induced depression were investigated by examining monoaminergic gene expression, protein levels and neurotransmitter levels in rat brain tissue and plasma and an in vitro model. The majority of serotonergic components (SERT, 5-HT1AR, 5-HT1BR and MAOA) were not altered by chronic 13-cis-RA treatment, with the possible exception of TPH2 gene/protein expression and increased 5-HT levels in platelets. In fact, the expression of D2 dopamine receptor was significantly elevated in the RN46A-B14 cell line (10μM 13-cis-RA, 48 h) and was similarly elevated at the protein level in the juvenile rat hippocampus (1mg/kg/day, i.p., 6 weeks), suggesting dopaminergic pathways may be of importance. There was also a trend in the data to suggest that 13-cis-RA-treated juvenile rats may be more susceptible the molecular alterations than corresponding adult rats. xii
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A Study of Menace, Pause and Silence in Harold Pinter’s Early PlaysPishali Bajestani, Behnam January 2012 (has links)
The particular characteristics of Pinter’s theatre such as the theme of violence, the competitive interpersonal relationships, the implied unwillingness in communication between the characters and the distinctive use of silences and pauses, distinguish his work from the writers of the absurd. Pinter makes particular use of “Silences” and “Pauses” as theatrical techniques that present a non-verbal way of communication in his plays. The frequent use of these particular techniques in Pinter’s dialogue has urged some critics to coin new expressions such as “Pinteresque” or “Pinter Pause” in the vocabulary of drama to specify Pinter’s technique. One of the important objectives in this essay is to point out the fundamental significance and function of the “Silences” and “Pauses” in Pinter’s work and point out their distinction. I will discuss how the silences and pauses function in Pinter’s theatre as a non-verbal way of communication by creating fragments in the dialogue. The plays which will be analyzed in this essay are: The Room, The Dumb Waiter, The Birthday Party and The Caretaker. My objective in this essay is to explore the context of these plays with regards to the theme of menace. In the first chapter, I mainly aim to explore the menacing context of these plays regarding the structure of menace and the ways it takes place in each play separately. This analysis will be presented in relation to the spatial territory in which the characters are confined. My aim is also to describe why menace is presented in a theatrical sense. I have chosen to quote some significant passages of each play in each section to illustrate my purposes in the first chapter. The aim of the second chapter is to define the character types involved in the presentation of menace, “The Intruders” and “The Victims”, and to analyze the strategies their use in encounters with each other. After describing the character types I will explore in detail how “The Intruders” use linguistic strategies to confuse and subdue their victims and finally victimize them and how “The Victims” use strategies to cope with menace in order to survive. There are some passages quoted from the plays to facilitate the purpose of the second chapter. The objective in the third chapter is to define “Silences” and “Pauses” as theatrical techniques used in form of non-verbal communication between the characters. I will discuss, based on Peter Hall’s definition, how these techniques are significant in understanding a Pinter play for the readers and the actors who perform them on stage, and will further explore the function of “Silences” and “Pauses” and their distinction in the context of the plays in question in this essay.
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Intruder Dynamic Response in Particulate MediaWarnakulasooriya, Niranjan Mahaguruge 01 May 2017 (has links)
Many everyday materials, broadly classified as ``particulate media'', are at the heart of many industries and natural phenomena. Examples range from the storage and transport of bulk foods and aggregates such as grains and coal; the processing of pharmaceutical pills and the grinding coffee beans; to the mitigation and cost control of life-threatening events like landslides, earthquakes, and silo failures. The common theme connecting all these phenomena is the mechanical stability of the granular material that arises from interactions at the microscopic level of the grain scale, and how this influences collective properties at the bulk, macroscopic scale. In this dissertation, we present an extensive study of the mechanical properties of a physics-based model of granular particle systems in two dimensions using computer simulations. Specifically, we study the dynamics of an intruder particle that is driven through a dense, disordered packing of particles. This practical technique has the benefit of being amenable to experimental application which we expect will motivate future studies in the area. We find the `microrheology' of the intruder can be traced back to the properties of underlying, original, unperturbed packing, thereby providing a method to characterize the mechanical properties of the material that may otherwise be unavailable. To perform this study, we initially created mechanically stable granular packings of bidisperse discs, for several orders of magnitude of particle friction coefficient $\mu$, over a range in packing densities, or packing fractions $\phi$, in the vicinity of the critical packing fraction $\phi_c$, the density below which the packing is no longer stable. This range in $\phi$ translates to a range in packing pressures $P$, spanning several orders of magnitude down to the $P\rightarrow 0$ limit. For each packing, we apply a driving force to the intruder probe particle and find the critical force $F_{c}$, the minimum force required to induce motion of the probe as it is dragged through the system. We find that $F_{c}(\mu)$ for the different friction packings, scales with the packing pressure $P$ as a power-law according to: $F_{c}(\mu) - F_{c}^{o}(\mu) \sim P^{\beta(\mu)}$. The power-law exponent, $\beta(\mu)$ becomes friction dependent, but approaches the value, $\beta(\mu\to0) = 1.0 \pm 0.1$ in the zero-friction limit. $F_{c}^{o}(\mu)$ is the value of $F_{c}$ in the limit $P \to 0$, that similarly depends on the friction coefficient as, $F_{c}^{o}(\mu) \to 0$, when $\mu \to \infty$. We use this property of $F_{c}^{o}(\mu)$ to characterize the mechanical properties of different frictional packings. Another focus of this study is the `microrheology' of the intruder through force-velocity dependencies in $\mu=0$ systems at different $P$. For this case, the intruder is driven through the packing at a steady-state velocity $$, for driving forces above the critical force $F_D > F_c$. We introduce a scaling function that collapses the force-velocity curves onto a single master curve. This power law scaling of the collapsed curve as $P\rightarrow 0$ is reminiscent of a continuous phase transition, reinforcing the notion that the mechanical state of the system exhibits critical-like features. Furthermore, we also find an alternative scaling collapse of the form: $- \sim (F_{D} - F_{c})^{\alpha}$, where $$ represents a constant velocity term in the limit of small excess forcing, and the critical force $F_{c}$ now appears as fitting parameter that matches our explicit calculations. Thence, we are able to extract $F_{c}$ from a driven probe without a-priori having any knowledge about the state of the system. To further investigate the transition of the system through the different intruder force perturbations, we implemented a coarse graining (CG) technique that transforms our discrete particle interaction force information into continuous stress fields. Through this methodology, we are able to calculate the kinetic and contact stresses as the intruder is driven through the system. We are able to qualify and quantify the directional and distance dependencies of the stress response of the packing due to the driven probe via radial and azimuthal stress calculations. In particular, we find how the stress response not only captures the wake region behind the driven intruder, but also how the stress decays in the forward direction of the intruder, which follows universal behavior.
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A Test of the Female Mimicry Hypothesis in Painted Buntings (Passerina ciris)Gurley, Christine E 05 1900 (has links)
While female mimicry and lower status signaling hypotheses of delayed plumage maturation have received much discussion in the literature, the experimental tests of these hypotheses have been infrequent. Those experimental tests often use a simulated intruder method with artificial model intruders rather than using live conspecific birds as intruders. Subadult male painted buntings (Passerina ciris) possess delayed plumage maturation where they appear visually identical to adult females during their first potential breeding season, while adult males are strikingly different in plumage coloration. Here I test the behavioral responses in a territorial population of painted buntings that exhibits extreme delayed plumage maturation using a simulated territorial intrusion experiment to measure territorial male behavioral response when presented with live caged intruders of both subadult and adult males. Territorial adult males were significantly more likely to initiate an attack and continue to attack caged adult male intruders than compared to caged subadult male intruders. This result supports both the female mimicry and status signaling hypotheses, and does not support the cryptic hypothesis. Additionally, in anecdotal observations, territorial males occasionally performed mating display behaviors to caged subadult male intruders. These results further suggest that territorial male painted buntings may identify subadult males as potential mates, supporting the female mimicry hypothesis for subadult males in this species. To what degree subadult males may benefit from DPM deserves further study.
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Possible Interactions of Serotonin and Oxytocin in the Neural Regulation of Aggressive BehaviorHazlett, Emily G. 15 May 2012 (has links)
No description available.
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Efeitos do canabidiol no comportamento agressivo induzido por isolamento social em camundongos / Cannabidiol effects on agressive-like behaviors induced by social isolation in miceAlice Hartmann dos Santos 28 January 2016 (has links)
O Canabidiol (CBD), principal composto não-psicotomimético da Cannabis sativa, possui diversas propriedades farmacológicas, incluindo a indução de efeitos tipoantidepressivos e ansiolíticos em roedores após administração sistêmica. O isolamento social aumenta comportamentos agressivos em camundongos, condição denominada agressão induzida pelo isolamento social ou agressão territorial. Drogas ansiolíticas e antidepressivas podem atenuar comportamentos agressivos. Desse modo, o objetivo do presente trabalho foi avaliar se o CBD atenuaria comportamentos agressivos induzidos pelo isolamento social em camundongos. Camundongos Suíços machos (7-8 semanas de idade no dia do isolamento, 30-40 g no dia do teste) foram mantidos isolados (camundongos residentes) para indução dos comportamentos agressivos. Paralelamente, camundongos co-específicos (camundongos intrusos) foram mantidos agrupados (oito por caixa). Neste modelo, um camundongo intruso da mesma linhagem, sexo e idade foi colocado na caixa moradia do residente. As interações entre os camundongos residente e intruso foram gravadas por 20 min e a latência para a primeira mordida contra o intruso, o número de ataques e o tempo total de ataques foram analisados por um observador cego aos grupos experimentais. Após 10 dias de isolamento social, foi testado se a administração aguda (i.p.) de CBD (5, 15, 30 ou 60 mg/kg), 30 min antes do teste, atenuaria comportamentos agressivos dos camundongos residentes contra os intrusos. Para avaliar a participação de receptores 5-HT1A e CB1 nos efeitos do CBD, grupos independentes de animais receberam 1 injeção prévia de WAY 100635 (antagonista dos receptores 5-HT1A, 0,3 mg/kg) ou AM251 (antagonista dos receptores CB1, 1 mg/kg), 30 min antes do CBD (15 mg/kg). Para controlar possíveis efeitos motores da droga, grupos independentes de animais tratados com doses efetivas de CBD ou não efetivas de WAY100635 ou AM251 foram submetidos ao actímetro para avaliação da atividade locomotora total. O CBD (15 mg/kg) aumentou a latência para o residente atacar o intruso e este efeito foi atenuado tanto pela administração prévia de AM251 (VEI+VEI: 186,62±83,16; VEI+CBD: 956,25±150,77; AM+VEI: 271,71±156,18; AM+CBD: 395,86±208,24; p=0,030) quanto WAY100635 (VEI+VEI: 116,33±29,38; VEI+CBD: 860,87±177,36; WAY+VEI: 305,12±159,16; WAY+CBD: 302,57±154,68; p=0,011). Além disso, o CBD reduziu o número de ataques em todas as doses testadas (VEI: 23,00±3,66; CBD 5: 12,25±2,43; CBD 15: 6,62±2,43; CBD 30: 7,71±3,24; CBD 60: 8,16±2,36; p=0,002) e as doses intermediárias (15 e 30 mg/kg) foram capazes de diminuir o tempo total de ataques (VEI: 114,37±22,65; CBD 5: 80,87±23,83; CBD 15: 40,00±14,58; CBD 30: 25,86±12,88; CBD 60: 54,67±9,68; p=0,018), ambos os efeitos sendo atenuados pelo AM251 (Número de ataques - VEI+VEI: 19,25±2,56; VEI+CBD: 3,25±2,36; AM+VEI: 22,86±4,97; AM+CBD: 14,14±4,10; p=0,028; Tempo total de ataques - VEI+VEI: 66,62±9,19; VEI+CBD: 11,75±9,56; AM+VEI: 118,86±31,00; AM+CBD: 58,71±17,45; p=0,049) e WAY100635 (Número de ataques - VEI+VEI: 30,83±6,77; VEI+CBD: 7,87±4,68; WAY+VEI: 22,50±5,06; WAY+CBD: 23,57±6,74; p=0,059; Tempo total de ataques - VEI+VEI: 151,17±32,65; VEI+CBD: 16,75±10,88; WAY+VEI: 113,75±24,66; WAY+CBD: 76,29±21,36; p=0,002). Não foi observado efeito motor do CBD em nenhuma das doses testadas, bem como do WAY100635 e AM251. Esses resultados evidenciam que o CBD atenua comportamentos agressivos em camundongos e nos permitem sugerir um mecanismo misto, visto que há o envolvimento de receptores CB1 e 5-HT1A. Desse modo, este fitocanabinoide poderia ser uma alternativa terapêutica para tratar comportamentos agressivos associados a transtornos psiquiátricos / Cannabidiol (CBD), a major non-psychotomimetic compound from Cannabis sativa plant, induces anxiolytic- and antidepressant-like effects in rodents after systemic administration. Long-term individual housing increases aggressive behavior in mice, a condition named isolation-induced aggression or territorial aggression, which can be attenuated by anxiolytic and antidepressant drugs. Thus, the aim of the present study was to verify whether CBD would attenuate the aggressive behavior induced by social isolation. Male Swiss mice (7-8 weeks of age on the isolation day, 30-40 g on the test day) were individually housed (resident mice) to induce aggressive behavior, while conspecific mice (intruder mice) were grouped housed (eight per cage). In this model, an intruder mouse of the same strain, sex and age is placed in the resident home cage. The resident-intruder interactions were videotaped for 20 min and the latency to the first bite against the intruder, the number of attacks and the total duration of aggressive encounters were recorded and later analyzed by an observer blind to the treatment groups. After 10 days of social isolation, we tested if acute intraperitoneal CBD administration (5, 15, 30 and 60 mg/kg) to the resident mice 30 min prior to the test would attenuate aggressive-like behavior towards the intruder animal. To evaluate the involvement of 5-HT1A and CB1 receptors in the CBD effects, independent groups of animals were injected with WAY100635 (0.3 mg/kg) or AM251(1 mg/kg) 30 min prior to CBD (15 mg/kg). To control possible motor effects, independent animals treated with effective doses of CBD or ineffective doses of WAY100635 or AM251 were submitted to the actimeter to evaluate the total locomotor activity. CBD (15 mg/kg) increased latency to attack the intruder and this effect was attenuated by the prior administration of AM251 (VEI+VEI: 186.62±83.16; VEI+CBD: 956.25±150.77; AM+VEI: 271.71±156.18; AM+CBD: 395.86±208.24; p=0.030) or WAY100635 (VEI+VEI: 116.33±29.38; VEI+CBD: 860.87±177.36; WAY+VEI: 305.12±159.16; WAY+CBD: 302.57±154.68; p=0.011). Moreover, CBD reduced the number of attacks in all tested doses (VEI: 23.00±3.66; CBD 5: 12.25±2.43; CBD 15: 6.62±2.43; CBD 30: 7.71±3.24; CBD 60: 8.16±2.36; p=0.002) as well as the duration of aggressive behavior encounters in the intermediary doses (15 and 30 mg/kg; VEI: 114.37±22.65; CBD 5: 80.87±23.83; CBD 15: 40.00±14.58; CBD 30: 25.86±12.88; CBD 60: 54.67±9.68; p=0.018), both effects were attenuated by AM251 (Number of attacks - VEI+VEI: 19.25±2.56; VEI+CBD: 3.25±2.36; AM+VEI: 22.86±4.97; AM+CBD: 14.14±4.10; p=0.028; Total time of attacks - VEI+VEI: 66.62±9.19; VEI+CBD: 11.75±9.56; AM+VEI: 118.86±31.00; AM+CBD: 58.71±17.45; p=0.049) and WAY100635 (Number of attacks - VEI+VEI: 30.83±6.77; VEI+CBD: 7.87±4.68; WAY+VEI: 22.50±5.06; WAY+CBD: 23.57±6.74; p=0.059; Total time of attacks - VEI+VEI: 151.17±32.65; VEI+CBD: 16.75±10.88; WAY+VEI: 113.75±24.66; WAY+CBD: 76.29±21.36; p=0.002). CBD, in all tested doses, as well as WAY100635 and AM251, did not induce locomotor changes. These findings suggest that CBD decreases aggressive behaviors in mice and allow us to suggest that this effect involves CB1 and 5-HT1A receptors. Therefore, this phytocannabinoid may be therapeutically useful to treat aggressive behaviors that are usually associated with psychiatric disorders
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