Detection of Gray Hole Attack in Software Defined Networks

Gray Hole Attack is an advanced transformation of black hole attack. Both of them are a common type of attack in Wireless Sensor Network (WSN). Malicious nodes may constantly or randomly drop packets and therefore reduce the efficiency of the networking system. Furthermore Software Define Network (SDN) has been highly developed in recent years. In this type of networks switch/router functionality is separated into the control plane and data plane. Network managers can select control policies and build operating rules according to their own preferences. In addition, network protocols and packet fields are also programmable. Because the switch/router only implements the data transmission and executes the switching/routing decisions based on commends coming from control plane. Compromised switches/routers themselves or malicious control instructions both can result in selectively dropped packets. This makes a gray hole attack possible in the infrastructure of SDN. Therefore, this paper would like to discuss time-base and random-base gray hole attack in SDN, and then propose a useful detection method based on weighted K-Nearest Neighbor (KNN) and Genetic Algorithm (GA). The simulation data collected from switches/routers indicate that our method does demonstrate pretty good performance

PROPERTIES OF THE TOMBUSVIRUS MOVEMENT PROTEIN AND RNAi SUPPRESSOR THAT INFLUENCE PATHOGENESIS

Tomato bushy stunt virus (TBSV) provides a good model system to investigate molecular virus-host interactions in plants. P22 and P19 proteins encoded by TBSV contribute to multiple invasion-associated functions. Green fluorescence-mediated visualization of TBSV invasion in this study suggests that virus exit from inoculated epidermal cells is a crucial event. Close examination of one P22 mutant showed that it had lost the capacity to move between epidermis and mesophyll which was possibly due to an altered subcellular localization. P19 is a potent suppressor of RNA interference (RNAi) in various systems by forming dimers that bind 21-nucleotide (nt) duplex siRNAs (short interfering RNAs), to affect the programming of the RNA-induced silencing complex (RISC). P19 is attractive for biotechnological and research purposes to prevent RNAi of certain value-added genes in plants. To obtain a good plant-based expression platform, a suppression-active mutant P19 was expressed in transgenic N. benthamiana lines. This is the first example of P19 accumulating to detectable levels in a transgenic plant and initial results suggest it is actively suppressing RNAi. Furthermore, to investigate the correlation between siRNA binding of P19 and its various biological roles, predicted siRNA-interacting sites of TBSV P19 were modified, and the corresponding TBSV mutants were used to inoculate plants. Substitutions on siRNA-contact sites on the central domain of P19 resulted in more severe symptoms in N. benthamiana compared to those affecting peripheral regions. All tested combinations of siRNA-binding mutations were associated with reduced accumulation of total TBSV-derived siRNAs, and loss of siRNA sequestration by P19. Additionally, some modifications were found to cause RNAi-mediated disappearance of viral and host materials in N. benthamiana but not in spinach. In conclusion, exit out of epidermal cells is a key host range determinant for TBSV and particular amino acids on P22 may influence this by regulating the proper subcellular localization. Mutant P19 transgenic plants were successfully established with minor physiological effects to be applied as a platform to study RNAi and to over-express proteins. Finally, a compromised P19-siRNA binding impacts symptom development, systemic invasion, integrity of virus plus host RNA and proteins, and that all in a hostdependent manner

Dynamic computation migration in distributed shared memory systems

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1995.Vita.Includes bibliographical references (p. 123-131).by Wilson Cheng-Yi Hsieh.Ph.D

Psychosocial Determinants of Insomnia in Adolescents: Roles of Mental Health, Behavioral Health, and Social Environment

The theoretical explanation of human problems is derived from the complex interplay of psychological, social, economic, political, and physical factors. Aims: This study examined the roles of behavioral health (i.e., alcohol abuse and suicidality) and social environment (i.e., family support, school connectedness, and favorable neighborhood) and mental health [i.e., depression, anxiety, and attention deficit hyperactivity disorder (ADHD)] in predicting insomnia in adolescents in an ecological perspective. Methods: Approximately 6445 high school students in Taiwan were administered an anonymous self-report survey. Hierarchical multiple regression was performed to examine how multidimensional social environment, behavioral health, and mental health factors were associated with insomnia in adolescents. Results: The prevalence rate of insomnia in the sample was 30%. The results indicated that alcohol abuse (β = 0.04), suicidality (β = 0.06), depression (β = 0.29), anxiety (β = 0.14), and ADHD (β = 0.11) were positively associated with insomnia (p \u3c 0.001), whereas family support (β = −0.06), school connectedness (β = −0.05), and favorable neighborhood (β = −0.10) were negatively associated with insomnia (p \u3c 0.001). Sex did not predict insomnia, but age was positively associated with insomnia (β = 0.09, p \u3c 0.001). Among all predictors of insomnia in the study, mental health factors, especially depression, play a major role on insomnia among adolescents, and is as much important as social environment factors. Conclusion: This study demonstrated how both psychosocial variables (social environment and behavioral health) and psychological symptoms were associated with insomnia in adolescents when the demographic variables (sex and age) were controlled and provided valuable information and evidence for clinicians, social workers, and health professionals who provide support to adolescents with insomnia. Applying an ecological approach in practice can aid in understanding at individual, family, school, and community levels and in identifying the strengths and weaknesses of their interactions with each other. Implications: This perspective enables practitioners in effectively treating problems and addressing the needs of the various levels, including the individual, family, school, and the broader community. Thus, prevention and intervention of insomnia in adolescents should focus on multidimensional risk and protective factors, including mental health, behavioral health, and social environment, in the context of an ecological system

The History, Mechanism, and Clinical Application of Auricular Therapy in Traditional Chinese Medicine

Auricular therapy includes acupuncture, electroacupuncture, acupressure, lasering, cauterization, moxibustion, and bloodletting in the auricle. For 2500 years, people have employed auricular therapy for treating diseases, but the methods have been limited to bloodletting and cauterization. Only after 1957, the international scientific community became aware that the map of the ear resembles an inverted fetus, its introduction has led to auricular acupuncture (AA) becoming a more systemic approach, and, following the identification and standardization of more precise points, AA has been employed in clinical applications. The mechanisms of AA are considered to have a close relationship with the autonomic nervous system, the neuroendocrine system, neuroimmunological factors, neuroinflammation, and neural reflex, as well as antioxidation. Auricular therapy has been applied, for example, for pain relief, for the treatment of epilepsy, anxiety, and obesity, and for improving sleep quality. However, the mechanisms and evidence for auricular therapy warrant further study

Development and Validation of the Parents\u27 Perceived Self-Efficacy to Manage Children\u27s Internet Use Scale for Parents of Adolescents with Attention-Deficit/Hyperactivity Disorder

Background and aims: This study developed and validated the Parents’ Perceived Self-Efficacy to Manage Children’s Internet Use Scale (PSMIS) in the parents of children with attention-deficit/hyperactivity disorder (ADHD). Methods: In total, 231 parents of children with ADHD were invited to complete the PSMIS, followed by the Chen Internet Addiction Scale and the short version of Swanson, Nolan, and Pelham, Version IV Scale – Chinese version for analyzing Internet addiction severity and ADHD symptoms, respectively. Results: The results of exploratory and confirmatory factor analyses confirmed the four-factor structure of the 18-item PSMIS. The significant difference in the levels of parents’ perceived self-efficacy between the parents of children with and without Internet addiction supported the criterion-related validity of the PSMIS. The internal consistency and 1-month test–retest reliability were acceptable. Conclusion: The results indicate that the PSMIS has acceptable validity and reliability and can be used for measuring parents’ perceived self-efficacy to manage children’s Internet use among parents of children with ADHD