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Cellular communication network factor 2 (CCN2) is a matricellular protein that plays important roles in connective tissue. CCN2 is also expressed in the nervous system; however, its role is still unclear. To explore CCN2 function in the brain, we generated forebrain‐specific Ccn2 knockout (FbCcn2 KO) mice. In this study, we examined the behavioral phenotypes of FbCcn2KO mice. Male mice lacking CCN2 in the forebrain exhibited normal locomotion, sensorimotor gating, and social behaviors but signs of anxiety and elevated reactive aggression. We checked the c‐fos expression in aggression‐related brain regions following the resident‐intruder task (RIT), an aggression test. RIT‐induced c‐fos levels in the medial amygdala (MeA) were higher in FbCcn2−/− mice as compared to controls. However, in the prefrontal cortex, RIT‐induced c‐fos levels in FbCcn2−/− mice were lower than controls. Our results suggested in male mice lacking CCN2 in the olfaction‐related regions, olfactory social cues elicit greater signals in the MeA, resulting in greater reactive aggression in the RIT. Further, lacking CCN2 in the prefrontal cortex, the major area related to inhibitory control and emotion regulation, may lead to signs of anxiety and the failure to suppress aggressive behaviors. Our model is useful in elaborating the mechanism underlying reactive aggression and therapeutic strategies. Cellular communication network factor 2 (CCN2) is expressed in the olfactory bulb, anterior olfactory nucleus, frontal cortex (FC), and cortical layer IVb. Intruder mice elicit greater neuronal signals in the medial amygdala, in mice lacking CCN2, resulting in greater reactive aggression during resident‐intruder task. Further, lacking CCN2 in the FC, may lead to the failure of suppressing aggressive behaviors.

The current study investigated stress‐induced aggressive behavior in the resident‐intruder test in males of the genetically stress hyper‐reactive Wistar Kyoto More Immobile (WMI), and the nearly isogenic, control Wistar Kyoto Less Immobile (WLI) strains. Tests were carried out against same‐age intruders during adolescence, and same‐age and juvenile intruders in adulthood. In adolescence and adulthood, prior acute restraint stress decreased social interactions and decreased aggressive behaviors of adolescents and adult WLIs. However, prior stress precipitated aggression in the adult WMI males toward both same‐age, and juvenile intruders compared with control WMIs and WLIs. Trunk blood levels of testosterone and androstenedione increased in stressed WLIs, but not in WMIs, suggesting no direct role of androgens in the increased aggression of WMIs. Expressions of aggression‐relevant genes showed patterns commensurate with being causative in aggressive behavior. The methyl‐CpG binding protein 2 was lower in the frontal cortex of control WMIs, and in the amygdala of stressed WMIs compared with their respective WLIs. Frontal cortex expression of vasopressin receptor 1a and serotonin transporter increased, solely in WMI males after stress. As behaviors were the same toward same‐age and non‐threatening juvenile intruders, the stress‐induced increase in confrontational behavior of the adult WMI male was not because of enhanced fear or anxiety. These results suggest that genetic stress hyper‐reactivity is a risk factor for stress‐induced increases in aggression in males. Additionally, as known aggression‐related genes showed expression patterns paralleling aggressive behavior, this model system could identify novel molecular pathways leading to stress‐enhanced aggression. Genetically stress hyper‐reactive adult males showed enhanced aggressive behavior, unrelated to fear or anxiety, toward same‐age and nonthreatening juvenile intruders after stress. In contrast, prior stress decreased aggressive behavior of the nearly isogenic control males. Of the aggression related genes, stress‐ and strain‐related changes in the expression of arginine vasopressin receptor 1a and the serotonin transporter are likely causally related to stress‐enhanced aggression in vulnerable individuals.

Between 1960 and 1990, 95% of the black rhino population in the world was killed. In South Africa, a rhino was killed every 8 h for its horn throughout 2016. Wild animals, rhinos and elephants, in particular, are facing an ever increasing poaching crisis. In this paper, we review poaching detection technologies that aim to save endangered species from extinction. We present requirements for effective poacher detection and identify research challenges through the survey. We describe poaching detection technologies in four domains: perimeter based, ground based, aerial based, and animal tagging based technologies. Moreover, we discuss the different types of sensor technologies that are used in intruder detection systems such as: radar, magnetic, acoustic, optic, infrared and thermal, radio frequency, motion, seismic, chemical, and animal sentinels. The ultimate long-term solution for the poaching crisis is to remove the drivers of demand by educating people in demanding countries and raising awareness of the poaching crisis. Until prevention of poaching takes effect, there will be a continuous urgent need for new (combined) approaches that take up the research challenges and provide better protection against poaching in wildlife areas.

The fast and efficient directed motion of particles through crowded environments is challenging problem. In this work, the surface-bound motion of an intruder in a crowd of identical active agents is studied by overdamped Langevin dynamics simulations. Both intruder and agents are modeled as intelligent active Brownian particles (iABPs) with visual perception and directional steering to avoid collisions - which implies non-reciprocal interactions between all particles. The reorientation of intruder and agents is limited by their maximal maneuverability, which controls the ability of an iABP to adjust its velocity direction. The simulation results show that the intruder’s attempt to increase directional speed by steering around agents fails; in fact, this even reduces the directional speed. In contrast, the intruder has to be perceived by the agents so that they can move out of the way in time. The intruder speed and transverse diffusivity are determined as functions of several key control parameters, like maneuverability, vision angle, and agent density. Here, an important parameter is the uniformity of the agent distribution. It is shown that the agent’s self-steering to avoid collision enhances hyperuniformity (class III), which facilitates an easier directional navigation of the intruder. Results are relevant, inter alia, for the motion of emergency personnel in semi-dense human crowds.

Background: Aggressive behaviors are one of the most important negative behaviors that seriously endangers human health. Also, the central para-inflammation of microglia triggered by stress can affect neurological function, plasticity, and behavior. NLRP3 integrates stress-related signals and is a key driver of this neural para-inflammation. However, it is unclear whether the NLRP3 inflammasome is implicated in the development of aggressive behaviors. Methods: First, aggressive behavior model mice were established using the resident intruder paradigm. Then, aggressive behaviors were determined with open-field tests (OFT), elevated plus-maze (EPM), and aggressive behavior tests (AT). Moreover, the expression of P2X7R and NLRP3 inflammasome complexes were assessed by immunofluorescence and Western blot. The levels of NLRP3 and inflammatory cytokines were evaluated using enzyme-linked immunosorbent assay (ELISA) kits. Finally, nerve plasticity damage was observed by immunofluorescence, transmission electron microscope, and BrdU staining. Results: Overall, the resident intruder paradigm induced aggressive behaviors, activated the hippocampal P2X7R and NLRP3 inflammasome, and promoted the release of proinflammatory cytokines IL-1β in mice. Moreover, NLRP3 knockdown, administration of P2X7R antagonist (A804598), and IL-1β blocker (IL-1Ra) prevented NLRP3 inflammasome-driven inflammatory responses and ameliorated resident intruder paradigm-induced aggressive behaviors. Also, the resident intruder paradigm promoted the activation of mouse microglia, damaging synapses in the hippocampus, and suppressing hippocampal regeneration in mice. Besides, NLRP3 knockdown, administration of A804598, and IL-1Ra inhibited the activation of microglia, improved synaptic damage, and restored hippocampal regeneration. Conclusion: The NLRP3 inflammasome-driven inflammatory response contributed to resident intruder paradigm-induced aggressive behavior, which might be related to neuroplasticity. Therefore, the NLRP3 inflammasome can be a potential target to treat aggressive behavior-related mental illnesses.

In rodents, repeated exposure to unavoidable aggression followed by sustained sensory treat can lead to prolonged social aversion. The chronic social defeat stress model explores that phenomenon and it has been used as an animal model for human depression. However, some authors have questioned whether confounding effects may arise as the model also boosts anxiety-related behaviors. Despite its wide acceptance, most studies extract limited information from the behavior of the defeated animal. Often, the normalized occupancy around the social stimulus, the interaction zone, is taken as an index of depression. We hypothesized that this parameter is insufficient to fully characterize the behavioral consequences of this form of stress. Using an ethological approach, we showed that repeated social defeat delayed the expression of social investigation in long (10 min) sessions of social interaction. Also, the incidence of defensive behaviors, including stretched-attend posture and high speed retreats, was significantly higher in defeated mice in comparison to controls. Interestingly, a subpopulation of defeated mice showed recurrent and non-habituating stretched-attend posture and persistent flights during the entire session. Two indexes were created based on defensive behaviors to show that only recurrent flights correlates with sucrose intake. Together, the present study corroborates the idea that this model of social stress can precipitate a myriad of behaviors not readily disentangled. We propose that long sessions (>150 s) and detailed ethological evaluation during social interaction tests are necessary to provide enough information to correctly classify defeated animals in terms of resilience and susceptibility to social defeat stress.

This paper aims to evaluate detection algorithms for perimeter security systems based on phase-sensitive optical time-domain reflectometry (Φ-OTDR). Our own designed and developed sensor system was used for the measurement. The main application of the system is in the area the perimeter fencing intrusion detection. The system is unique thanks to the developed motherboard, which contains a field-programmable gate array (FPGA) that takes care of signal processing. This allows the entire system to be integrated into a 1U rack chassis. A polygon containing two different fence types and also cable laid underground in a plastic tube was used for testing. Edge detection algorithms using the Sobel and Prewitt operators are considered for post-processing. The comparison is made based on the signal-to-noise ratio (SNR) values calculated for each event. Results of algorithms based on edge detection methods are compared with the conventional differential method commonly used in Φ-OTDR systems.

Lift and drag forces on moving intruders in flowing granular materials are of fundamental interest but have not yet been fully characterized. Drag on an intruder in granular shear flow has been studied almost exclusively for the intruder moving across flow streamlines, and the few studies of the lift explore a relatively limited range of parameters. Here, we use discrete element method simulations to measure the lift force, $F_{{L}}$ , and the drag force on a spherical intruder in a uniformly sheared bed of smaller spheres for a range of streamwise intruder slip velocities, $u_{{s}}$ . The streamwise drag matches the previously characterized Stokes-like cross-flow drag. However, $F_{{L}}$ in granular shear flow acts in the opposite direction to the Saffman lift in a sheared fluid at low $u_{{s}}$ , reaches a maximum value and then decreases with increasing $u_{{s}}$ , eventually reversing direction. This non-monotonic response holds over a range of flow conditions, and the $F_{{L}}$ versus $u_{{s}}$ data collapse when both quantities are scaled using the particle size, shear rate and overburden pressure. Analogous fluid simulations demonstrate that the flow around the intruder particle is similar in the granular and fluid cases. However, the shear stress on the granular intruder is notably less than that in a fluid shear flow. This difference, combined with a void behind the intruder in granular flow in which the stresses are zero, significantly changes the lift-force-inducing stresses acting on the intruder between the granular and fluid cases.

BackgroundAlcohol binge drinking may compromise the functioning of the nucleus accumbens (NAc), i.e. the neural hub for processing reward and aversive responses.MethodsAs socially stressful events pose particular challenges at developmental stages, this research applied the resident–intruder paradigm as a model of social stress, to highlight behavioural neuroendocrine and molecular maladaptive plasticity in rats at withdrawal from binge-like alcohol exposure in adolescence. In search of a rescue agent, cannabidiol (CBD) was selected due to its favourable effects on alcohol- and stress-related harms.ResultsBinge-like alcohol exposed intruder rats displayed a compromised defensive behaviour against the resident and a blunted response of the stress system, in addition to indexes of abnormal dopamine (DA)/glutamate plasticity and dysfunctional spine dynamics in the NAc. CBD administration (60 mg/kg) was able to: (1) increase social exploration in the binge-like alcohol exposed intruder rats, at the expenses of freezing time, and in control rats, which received less aggressive attacks from the resident; (2) reduce corticosterone levels independently on alcohol previous exposure; (3) restore DA transmission and (4) facilitate excitatory postsynaptic strength and remodelling.ConclusionsOverall, the maladaptive behavioural and synaptic plasticity promoted by the intersection between binge-like alcohol withdrawal and exposure to adverse social stress can be rescued by a CBD détente effect that results in a successful defensive strategy, supported by a functional endocrine and synaptic plasticity. The current data highlight CBD's relevant therapeutic potential in alcohol- and stress-related harms, and prompt further investigation on its molecular targets.

The cellular integrity of the kidney in homeostatic regulation has constantly been compromised by oxidative stress following exposure to varying nature of stressor present within the environment. The objective of the work was to evaluate the renal effect of the different stressor stimuli applied. Twenty-four adult female rats weighing averagely 160–200 g and within the ages of 12–14 weeks were used for experiment-1, while 12 offspring were utilized for experiment-2. Three stress models namely; restraint, mirror chamber and cat intruder stressors were used. Tissues were isolated from the animal and homogenized for tissue antioxidant assay. Serum was collected for assays of urea and creatinine for the kidney function test using ELISA. Data collected were analyzed for Mean ± SEM using One Way ANOVA. The present study revealed that exposure of rats to different stressors reduced relative kidney weights but did not significantly alter serum creatinine concentration in the Wistar rats, although the concentrations were slightly increased compared to controls. Urea concentration was significantly ( p  < 0.05) increased in rats exposed to restraint and intruder stressors. Exposure to a mirror chamber stressor did not significantly alter urea concentration. Offspring from parents of stressed female rats exhibited a significant ( p  < 0.05) increase in serum urea level, minimal increase in serum creatinine levels. GSH and GST levels showed no significant difference when compared to control group, whereas, GPx were significantly ( p  < 0.05) decreased irrespective of the stressor applied. SOD activity were significantly ( p  < 0.05) reduced in the group exposed to restraint or cat intruder stressor. CAT activities were significantly ( p  < 0.05) reduced in the rats exposed to restraint or cat intruder stressor. In all, the different stress model altered the antioxidant capacity of the kidney tissues. Exposure of rats to a stressful condition of the different nature of stressor has the tendency of compromising the functional integrity of the kidney, thus, with the potency of complicating female renal function.