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Sample records for minimizing malicious behavior

  1. Behavioral biometrics for verification and recognition of malicious software agents

    NASA Astrophysics Data System (ADS)

    Yampolskiy, Roman V.; Govindaraju, Venu

    2008-04-01

    Homeland security requires technologies capable of positive and reliable identification of humans for law enforcement, government, and commercial applications. As artificially intelligent agents improve in their abilities and become a part of our everyday life, the possibility of using such programs for undermining homeland security increases. Virtual assistants, shopping bots, and game playing programs are used daily by millions of people. We propose applying statistical behavior modeling techniques developed by us for recognition of humans to the identification and verification of intelligent and potentially malicious software agents. Our experimental results demonstrate feasibility of such methods for both artificial agent verification and even for recognition purposes.

  2. Associations between Peer Nominations, Teacher Ratings, Self-Reports, and Observations of Malicious and Disruptive Behavior

    ERIC Educational Resources Information Center

    Henry, David B.

    2006-01-01

    This study evaluates the validity of two aggression scales for predicting observations of malicious or disruptive behavior at school. Subgroups of a sample of 1,560 children (age 8.6 plus or minus 1.5 years) were assessed using (a) peer nominations of aggression, (b) teacher reports on the Teacher Report Form (TRF) of the Child Behavior Checklist…

  3. Behavioral analysis of malicious code through network traffic and system call monitoring

    NASA Astrophysics Data System (ADS)

    Grégio, André R. A.; Fernandes Filho, Dario S.; Afonso, Vitor M.; Santos, Rafael D. C.; Jino, Mario; de Geus, Paulo L.

    2011-06-01

    Malicious code (malware) that spreads through the Internet-such as viruses, worms and trojans-is a major threat to information security nowadays and a profitable business for criminals. There are several approaches to analyze malware by monitoring its actions while it is running in a controlled environment, which helps to identify malicious behaviors. In this article we propose a tool to analyze malware behavior in a non-intrusive and effective way, extending the analysis possibilities to cover malware samples that bypass current approaches and also fixes some issues with these approaches.

  4. Associations between peer nominations, teacher ratings, self-reports, and observations of malicious and disruptive behavior.

    PubMed

    Henry, David B

    2006-09-01

    This study evaluates the validity of two aggression scales for predicting observations of malicious or disruptive behavior at school. Subgroups of a sample of 1,560 children (age 8.6+/-1.5 years) were assessed using (a) peer nominations of aggression, (b) teacher reports on the Teacher Report Form (TRF) of the Child Behavior Checklist (CBCL) Aggression scale and the peer nomination items, or (c) self-reports on the peer nomination items. Criteria were observations of physical, verbal, initiated, retaliatory, malicious, and disruptive behaviors. Teacher report peer nominations predicted observed physical, verbal, initiated, and retaliatory aggression and disruptive behavior. Peer nominations predicted physical aggression, verbal aggression, initiation and disruptive behavior, and TRFs predicted verbal, initiated, and disruptive behavior. Self-reports did not significantly predict any behavior. Implications for assessment of aggression are discussed. PMID:16880277

  5. Malicious Hubs: Detecting Abnormally Malicious Autonomous Systems

    SciTech Connect

    Kalafut, Andrew J.; Shue, Craig A; Gupta, Prof. Minaxi

    2010-01-01

    While many attacks are distributed across botnets, investigators and network operators have recently targeted malicious networks through high profile autonomous system (AS) de-peerings and network shut-downs. In this paper, we explore whether some ASes indeed are safe havens for malicious activity. We look for ISPs and ASes that exhibit disproportionately high malicious behavior using 12 popular blacklists. We find that some ASes have over 80% of their routable IP address space blacklisted and others account for large fractions of blacklisted IPs. Overall, we conclude that examining malicious activity at the AS granularity can unearth networks with lax security or those that harbor cybercrime.

  6. Distinguishing congestion from malicious behavior in mobile ad-hoc networks

    NASA Astrophysics Data System (ADS)

    Ding, Jin; Medidi, Sirisha R.

    2004-08-01

    Packet dropping in Mobile Ad-hoc Networks could be a result of wireless link errors, congestion, or malicious packet drop attack. Current techniques for detecting malicious behavior either do not consider congestion in the network or are not able to detect in real time. Further more, they usually work at network layer. In this paper, we propose a TCP-Manet protocol, which reacts to congestion like TCP Reno protocol, and has additional capability to distinguish among congestion, wireless link error, and malicious packet drop attack. It is an end-to-end mechanism that does not require additional modifications to the nodes in the network. Since it is an extension of existing TCP protocol, it is compatible with existing protocols. It works in conjunction with the network layer and an unobtrusive monitor to assist the network in the detection and characterization of the nature of the behavior. Experimental results show that TCP-Manet has the same performance as that of TCP-Reno in wired network, and performs better in wireless ad-hoc networks in terms of throughput while having good detection effectiveness.

  7. Detection of malicious computer executables

    DOEpatents

    Cai, Dongming M.; Gokhale, Maya

    2009-04-14

    A method of detecting malicious binary executable files is accomplished by inputting a binary executable file; converting the binary executable file to byte hexadecimal text strings; calculating the frequency of each byte pattern in the byte hexadecimal text strings; selecting characteristic byte pattern frequencies as discriminating features; classifying the discriminating features as malicious or benign; labeling the binary executable file as malicious or benign; and outputting the labeled malicious or benign binary executable file.

  8. Anatomy of malicious singularities

    NASA Astrophysics Data System (ADS)

    Heller, Michael; Odrzygóźdź, Zdzisław; Pysiak, Leszek; Sasin, Wiesław

    2007-09-01

    As well known, the b boundaries of the closed Friedman world model and of Schwarzschild solution consist of a single point. We study this phenomenon in a broader context of differential and structured spaces. We show that it is an equivalence relation ρ, defined on the Cauchy completed total space E¯ of the frame bundle over a given space-time, that is responsible for this pathology. A singularity is called malicious if the equivalence class [p0] related to the singularity remains in close contact with all other equivalence classes, i.e., if p0ɛcl[p] for every p ɛE. We formulate conditions for which such a situation occurs. The differential structure of any space-time with malicious singularities consists only of constant functions which means that, from the topological point of view, everything collapses to a single point. It was noncommutative geometry that was especially devised to deal with such situations. A noncommutative algebra on E¯, which turns out to be a von Neumann algebra of random operators, allows us to study probabilistic properties (in a generalized sense) of malicious singularities. Our main result is that, in the noncommutative regime, even the strongest singularities are probabilistically irrelevant.

  9. Abnormally Malicious Autonomous Systems and their Internet Connectivity

    SciTech Connect

    Shue, Craig A; Kalafut, Prof. Andrew; Gupta, Prof. Minaxi

    2011-01-01

    While many attacks are distributed across botnets, investigators and network operators have recently targeted malicious networks through high profile autonomous system (AS) de-peerings and network shut-downs. In this paper, we explore whether some ASes indeed are safe havens for malicious activity. We look for ISPs and ASes that exhibit disproportionately high malicious behavior using ten popular blacklists, plus local spam data, and extensive DNS resolutions based on the contents of the blacklists. We find that some ASes have over 80% of their routable IP address space blacklisted. Yet others account for large fractions of blacklisted IP addresses. Several ASes regularly peer with ASes associated with significant malicious activity. We also find that malicious ASes as a whole differ from benign ones in other properties not obviously related to their malicious activities, such as more frequent connectivity changes with their BGP peers. Overall, we conclude that examining malicious activity at AS granularity can unearth networks with lax security or those that harbor cybercrime.

  10. Reliable Intersection Computation within Malicious Environments

    NASA Astrophysics Data System (ADS)

    Böttcher, Stefan; Obermeier, Sebastian

    A secure calculation of common data (D 1 ∩ ... ∩ D n ) of different participants without disclosing D i is useful for many applications and has been studied as the Secure Multiparty Computation problem. However, proposed solutions assume all participants act "semi-honest", which means participants may neither alter the protocol execution nor fake database content. In this contribution, we focus on malicious participant behavior and prove that an atomic exchange of common data is not possible under the assumption of malicious participants. We propose a mechanism to calculate the intersection of multiple participants, which does not only reduce the disclosure in case participants cheat by altering the protocol to a negligible amount, it is also resistant against malicious participants that cooperate in order to cheat others. Furthermore, it impedes database content faking, which could be done when using other protocols by participants in order to check if data is contained in the other's databases. Last, we show experimentally the practical usability of our protocol and how the level of trust has an impact on the exchange speed of the intersection.

  11. Towards a testbed for malicious code detection

    SciTech Connect

    Lo, R.; Kerchen, P.; Crawford, R.; Ho, W.; Crossley, J.; Fink, G.; Levitt, K.; Olsson, R.; Archer, M. . Div. of Computer Science)

    1991-01-01

    This paper proposes an environment for detecting many types of malicious code, including computer viruses, Trojan horses, and time/logic bombs. This malicious code testbed (MCT) is based upon both static and dynamic analysis tools developed at the University of California, Davis, which have been shown to be effective against certain types of malicious code. The testbed extends the usefulness of these tools by using them in a complementary fashion to detect more general cases of malicious code. Perhaps more importantly, the MCT allows administrators and security analysts to check a program before installation, thereby avoiding any damage a malicious program might inflict. 5 refs., 2 figs., 2 tabs.

  12. Identification of Malicious Web Pages by Inductive Learning

    NASA Astrophysics Data System (ADS)

    Liu, Peishun; Wang, Xuefang

    Malicious web pages are an increasing threat to current computer systems in recent years. Traditional anti-virus techniques focus typically on detection of the static signatures of Malware and are ineffective against these new threats because they cannot deal with zero-day attacks. In this paper, a novel classification method for detecting malicious web pages is presented. This method is generalization and specialization of attack pattern based on inductive learning, which can be used for updating and expanding knowledge database. The attack pattern is established from an example and generalized by inductive learning, which can be used to detect unknown attacks whose behavior is similar to the example.

  13. Evidence for surprise minimization over value maximization in choice behavior

    PubMed Central

    Schwartenbeck, Philipp; FitzGerald, Thomas H. B.; Mathys, Christoph; Dolan, Ray; Kronbichler, Martin; Friston, Karl

    2015-01-01

    Classical economic models are predicated on the idea that the ultimate aim of choice is to maximize utility or reward. In contrast, an alternative perspective highlights the fact that adaptive behavior requires agents’ to model their environment and minimize surprise about the states they frequent. We propose that choice behavior can be more accurately accounted for by surprise minimization compared to reward or utility maximization alone. Minimizing surprise makes a prediction at variance with expected utility models; namely, that in addition to attaining valuable states, agents attempt to maximize the entropy over outcomes and thus ‘keep their options open’. We tested this prediction using a simple binary choice paradigm and show that human decision-making is better explained by surprise minimization compared to utility maximization. Furthermore, we replicated this entropy-seeking behavior in a control task with no explicit utilities. These findings highlight a limitation of purely economic motivations in explaining choice behavior and instead emphasize the importance of belief-based motivations. PMID:26564686

  14. Automated assistance for detecting malicious code

    SciTech Connect

    Crawford, R.; Kerchen, P.; Levitt, K.; Olsson, R.; Archer, M.; Casillas, M.

    1993-06-18

    This paper gives an update on the continuing work on the Malicious Code Testbed (MCT). The MCT is a semi-automated tool, operating in a simulated, cleanroom environment, that is capable of detecting many types of malicious code, such as viruses, Trojan horses, and time/logic bombs. The MCT allows security analysts to check a program before installation, thereby avoiding any damage a malicious program might inflict.

  15. Differentiation of malicious and non-malicious fire-alarm calls using multidimensional scaling.

    PubMed

    Comber, M; Canter, D

    1983-10-01

    A pilot study was carried out to determine whether malicious and non-malicious fire alarm calls could be distinguished on the basis of their psycholinguistic attributes. Eight malicious and eight non-malicious calls were compared in terms of the number of speech errors of various kinds in the call. Using multi-dimensional scalogram analysis (MSA-I), it was possible to differentiate the two types of call on the basis of the over-all configuration of speech behaviour within the call. PMID:6634327

  16. Dispositional envy revisited: unraveling the motivational dynamics of benign and malicious envy.

    PubMed

    Lange, Jens; Crusius, Jan

    2015-02-01

    Previous research has conceptualized dispositional envy as a unitary construct. Recently however, episodic envy has been shown to emerge in two qualitatively different forms. Benign envy is related to the motivation to move upward, whereas malicious envy is related to pulling superior others down. In four studies (N = 1,094)--using the newly developed Benign and Malicious Envy Scale (BeMaS)--we show that dispositional envy is also characterized by two independent dimensions related to distinct motivational dynamics and behavioral consequences. Dispositional benign and malicious envy uniquely predict envious responding following upward social comparisons. Furthermore, they are differentially connected to hope for success and fear of failure. Corresponding to these links, dispositional benign envy predicted faster race performance of marathon runners mediated via higher goal setting. In contrast, dispositional malicious envy predicted race goal disengagement. The findings highlight that disentangling the two sides of envy opens up numerous research avenues. PMID:25534243

  17. Detecting and isolating malicious nodes in wireless ad hoc networks

    NASA Astrophysics Data System (ADS)

    Li, Fanzhi; Jassim, Sabah

    2007-04-01

    Malicious nodes can seriously impair the performance of wireless ad hoc networks as a result of different actions such as packet dropping. Secure routes are shortest paths on which every node on the route is trusted even if unknown. Secure route discovery requires the adoption of mechanisms of associating trust to nodes. Most existing secure route discovery mechanisms rely on shared keys and digital signature. In the absence of central nodes that act as certification authority, such protocols suffer from heavy computational burden and are vulnerable to malicious attacks. In this paper we shall review existing techniques for secure routing and propose to complement route finding with creditability scores. Each node would have a credit list for its neighbors. Each node monitors its neighbors' pattern of delivering packets and regularly credits are reviewed and updated accordingly. Unlike most existing schemes the focus of our work is based on post route discovery stage, i.e. when packets are transmitted on discovered routes. The level of trust in any route will be based on the credits associated with the neighbors belonging to the discovered route. We shall evaluate the performance of the proposed scheme by modifying our simulation system so that each node has a dynamic changing "credit list" for its neighbors' behavior. We shall conduct a series of simulations with and without the proposed scheme and compare the results. We will demonstrate that the proposed mechanism is capable of isolating malicious nodes and thereby counteracting black hole attacks.

  18. A Learning System for Discriminating Variants of Malicious Network Traffic

    SciTech Connect

    Beaver, Justin M; Symons, Christopher T; Gillen, Rob

    2013-01-01

    Modern computer network defense systems rely primarily on signature-based intrusion detection tools, which generate alerts when patterns that are pre-determined to be malicious are encountered in network data streams. Signatures are created reactively, and only after in-depth manual analysis of a network intrusion. There is little ability for signature-based detectors to identify intrusions that are new or even variants of an existing attack, and little ability to adapt the detectors to the patterns unique to a network environment. Due to these limitations, the need exists for network intrusion detection techniques that can more comprehensively address both known unknown networkbased attacks and can be optimized for the target environment. This work describes a system that leverages machine learning to provide a network intrusion detection capability that analyzes behaviors in channels of communication between individual computers. Using examples of malicious and non-malicious traffic in the target environment, the system can be trained to discriminate between traffic types. The machine learning provides insight that would be difficult for a human to explicitly code as a signature because it evaluates many interdependent metrics simultaneously. With this approach, zero day detection is possible by focusing on similarity to known traffic types rather than mining for specific bit patterns or conditions. This also reduces the burden on organizations to account for all possible attack variant combinations through signatures. The approach is presented along with results from a third-party evaluation of its performance.

  19. Revisiting the Efficiency of Malicious Two-Party Computation

    NASA Astrophysics Data System (ADS)

    Woodruff, David P.

    In a recent paper Mohassel and Franklin study the efficiency of secure two-party computation in the presence of malicious behavior. Their aim is to make classical solutions to this problem, such as zero-knowledge compilation, more efficient. The authors provide several schemes which are the most efficient to date. We propose a modification to their main scheme using expanders. Our modification asymptotically improves at least one measure of efficiency of all known schemes. We also point out an error, and improve the analysis of one of their schemes.

  20. Malicious Use of Nonpharmaceuticals in Children

    ERIC Educational Resources Information Center

    Yin, Shan

    2011-01-01

    Objective: The objective of this study was to describe malicious nonpharmaceutical exposures in children reported to US poison centers. Methods: We performed a retrospective study of all nonpharmaceutical exposures involving children 7 years old reported to the US National Poison Data System (NPDS) from 2000 to 2008 for which the reason for…

  1. Automatic recognition of malicious intent indicators.

    SciTech Connect

    Drescher, D. J.; Yee, Mark L.; Giron, Casey; Fogler, Robert Joseph; Nguyen, Hung D.; Koch, Mark William

    2010-09-01

    A major goal of next-generation physical protection systems is to extend defenses far beyond the usual outer-perimeter-fence boundaries surrounding protected facilities. Mitigation of nuisance alarms is among the highest priorities. A solution to this problem is to create a robust capability to Automatically Recognize Malicious Indicators of intruders. In extended defense applications, it is not enough to distinguish humans from all other potential alarm sources as human activity can be a common occurrence outside perimeter boundaries. Our approach is unique in that it employs a stimulus to determine a malicious intent indicator for the intruder. The intruder's response to the stimulus can be used in an automatic reasoning system to decide the intruder's intent.

  2. Secure Spectrum Data Fusion with Presence of Massive Malicious Users

    NASA Astrophysics Data System (ADS)

    Yao, Junnan; Zhu, Hongbo; Liu, Yan; Zhu, Benyu

    2015-05-01

    Malicious users are critical threats to the collaborative spectrum sensing (CSS) in cognitive radio networks. Especially with increasing number of malicious users, the performance of conventional malicious user detection (MUD) algorithms degrades fiercely. In this paper, we consider the secure CSS issue in the scenario that large number of malicious users exist in CSS system. We propose a new MUD algorithm, which detects the malicious users in a binary hypothesis test fashion. Based on the MUD, we provide a secure CSS approach. It is proved that the proposed secure CSS approach is insensitive with the number of malicious users, and it achieves a favorable performance even when a large number of malicious users are present.

  3. Malicious paraquat poisoning in Oklahoma dogs.

    PubMed

    Bischoff, K; Brizzee-Buxton, B; Gatto, N; Edwards, W C; Stair, E L; Logan, C

    1998-06-01

    Paraquat is a restricted use herbicide which is extremely toxic to companion animals when ingested. This report details one incident of malicious poisoning involving 6 dogs. All dogs were from the same geographic area, and 5 had pulmonary and renal lesions consistent with paraquat toxicosis. Diagnosis was initiated by a modified dithionite spot test on vomitus from 1 dog. Subsequent tissue paraquat levels ranged from non-detectable to 1 ppm. PMID:9610494

  4. Periodic Data Retrieval Problem in Rings Containing a Malicious Host

    NASA Astrophysics Data System (ADS)

    Královič, Rastislav; Miklík, Stanislav

    In the problems of exploration of faulty graphs, a team of cooperating agents is considered moving in a network containing one or more nodes that can harm the agents. A most notable among these problems is the problem of black hole location, where the network contains one node that destroys any incoming agent, and the task of the agents is to determine the location of this node. The main complexity measure is the number of agents needed to solve the problem. In this paper we begin with a study of malicious hosts with more varied behavior. We study the problem of periodic data retrieval which is equivalent to periodic exploration in fault-free networks, and to black hole location in networks with one black hole. The main result of the paper states that, in case of rings, it is sufficient to protect the internal state of the agent (i.e. the malicious host cannot change or create the content of agent's memory), and the periodic data retrieval problem is solvable by a constant number of agents.

  5. Minimal Social Networks Effects Evident in Cancer Screening Behavior

    PubMed Central

    Keating, Nancy L.; O’Malley, A. James; Murabito, Joanne M.; Smith, Kirsten P.; Christakis, Nicholas A.

    2010-01-01

    Background Social networks may influence screening behaviors. We assessed whether screening for breast, prostate, or colorectal cancer is influenced by the actual screening behaviors of siblings, friends, spouse, and coworkers. Methods Observational study using Framingham Heart Study data to assess screening for eligible individuals during the late 1990s. We used logistic regression to assess if the probability of screening for breast, prostate, or colorectal cancer was influenced by the proportion of siblings, friends, and coworkers who had the same screening, as well as spouse’s screening for colorectal cancer, adjusting for other factors that might influence screening rates. Results Among 1660 women aged 41–70, 71.7% reported mammography in the past year; among 1217 men aged 51–70, 43.3% reported prostate specific antigen testing in the past year; and among 1426 men and women aged 51–80, 46.9% reported stool blood testing and/or sigmoidoscopy in the past year. An increasing proportion of sisters who had mammography in the past year was associated with mammography screening in the ego (odds ratio [OR]=1.034, 95% confidence interval [CI]=1.000–1.065 for each 10% increase). A spouse with recent screening was associated with more colorectal cancer screening (OR 1.65, 95% CI=1.39–1.98 vs. unmarried). Otherwise, screening behaviors of siblings, friends, and coworkers were not associated with screening in the ego. Conclusion Aside from a slight increase in breast cancer screening among women whose sisters were screened and colorectal cancer screening if spouses were screened, the screening behavior of siblings, friends, or coworkers did not influence cancer screening behaviors. PMID:21264828

  6. Analysis of Malicious Traffic in Modbus/TCP Communications

    NASA Astrophysics Data System (ADS)

    Kobayashi, Tiago H.; Batista, Aguinaldo B.; Medeiros, João Paulo S.; Filho, José Macedo F.; Brito, Agostinho M.; Pires, Paulo S. Motta

    This paper presents the results of our analysis about the influence of Information Technology (IT) malicious traffic on an IP-based automation environment. We utilized a traffic generator, called MACE (Malicious trAffic Composition Environment), to inject malicious traffic in a Modbus/TCP communication system and a sniffer to capture and analyze network traffic. The realized tests show that malicious traffic represents a serious risk to critical information infrastructures. We show that this kind of traffic can increase latency of Modbus/TCP communication and that, in some cases, can put Modbus/TCP devices out of communication.

  7. Enhancing network robustness against malicious attacks.

    PubMed

    Zeng, An; Liu, Weiping

    2012-06-01

    In a recent work [Schneider et al., Proc. Natl. Acad. Sci. USA 108, 3838 (2011)], the authors proposed a simple measure for network robustness under malicious attacks on nodes. Using a greedy algorithm, they found that the optimal structure with respect to this quantity is an onion structure in which high-degree nodes form a core surrounded by rings of nodes with decreasing degree. However, in real networks the failure can also occur in links such as dysfunctional power cables and blocked airlines. Accordingly, complementary to the node-robustness measurement (R(n)), we propose a link-robustness index (R(l)). We show that solely enhancing R(n) cannot guarantee the improvement of R(l). Moreover, the structure of an R(l)-optimized network is found to be entirely different from that of an onion network. In order to design robust networks that are resistant to a more realistic attack condition, we propose a hybrid greedy algorithm that takes both the R(n) and R(l) into account. We validate the robustness of our generated networks against malicious attacks mixed with both nodes and links failure. Finally, some economical constraints for swapping the links in real networks are considered, and significant improvement in both aspects of robustness is still achieved. PMID:23005185

  8. Enhancing network robustness against malicious attacks

    NASA Astrophysics Data System (ADS)

    Zeng, An; Liu, Weiping

    2012-06-01

    In a recent work [Schneider , Proc. Natl. Acad. Sci. USAPNASA60027-842410.1073/pnas.1009440108 108, 3838 (2011)], the authors proposed a simple measure for network robustness under malicious attacks on nodes. Using a greedy algorithm, they found that the optimal structure with respect to this quantity is an onion structure in which high-degree nodes form a core surrounded by rings of nodes with decreasing degree. However, in real networks the failure can also occur in links such as dysfunctional power cables and blocked airlines. Accordingly, complementary to the node-robustness measurement (Rn), we propose a link-robustness index (Rl). We show that solely enhancing Rn cannot guarantee the improvement of Rl. Moreover, the structure of an Rl-optimized network is found to be entirely different from that of an onion network. In order to design robust networks that are resistant to a more realistic attack condition, we propose a hybrid greedy algorithm that takes both the Rn and Rl into account. We validate the robustness of our generated networks against malicious attacks mixed with both nodes and links failure. Finally, some economical constraints for swapping the links in real networks are considered, and significant improvement in both aspects of robustness is still achieved.

  9. Flunitrazepam abuse and malicious use in Texas, 1998-2003.

    PubMed

    Forrester, Mathias B

    2006-01-01

    Flunitrazepam is a potent benzodiazepine that is subject to abuse and malicious use. This study describes the patterns of flunitrazepam abuse and malicious use calls received by Texas poison centers during 1998-2003. The distribution of calls by year of call, geographic location of caller, patient gender and age, exposure site, and medical outcome were determined. There was no clear annual trend for abuse calls, but there was a consistent decline in the number of malicious use calls. A significantly higher percentage of abuse calls originated in south and west Texas and of malicious use calls in west Texas. Most abuse patients were males (55%) and adolescents (76%), and most of the exposures occurred in patient's own residence (68%), followed by school (16%). Most of the malicious use patients were females (93%) and adults (74%), and the greatest proportion of the exposures occurred in public areas (47%), followed by the patient's own residence (26%). The highest percentage of both abuse (48%) and malicious use (55%) involved minor effects. However, malicious use calls were significantly less likely to involve no effect (2% vs. 21%) and more likely to involve moderate effects (36% vs. 23%). Reported flunitrazepam abuse and malicious use calls in Texas differed with respect to geographic location of the caller, patient gender and age, exposure site, and medical outcome. Poison centers and health care providers might want to consider these differences when targeting populations for education and prevention efforts. PMID:16467007

  10. Detecting a malicious executable without prior knowledge of its patterns

    NASA Astrophysics Data System (ADS)

    Cai, Dongming M.; Theiler, James; Gokhale, Maya

    2005-03-01

    To detect malicious executables, often spread as email attachments, two types of algorithms are usually applied under instance-based statistical learning paradigms: (1) Signature-based template matching, which finds unique tell-tale characteristics of a malicious executable and thus is capable of matching those with known signatures; (2) Two-class supervised learning, which determines a set of features that allow benign and malicious patterns to occupy a disjoint regions in a feature vector space and thus probabilistically identifies malicious executables with the similar features. Nevertheless, given the huge potential variety of malicious executables, we cannot be confident that existing training sets adequately represent the class as a whole. In this study, we investigated the use of byte sequence frequencies to profile only benign data. The malicious executables are identified as outliers or anomalies that significantly deviate from the normal profile. A multivariate Gaussian likelihood model, fit with a Principal Component Analysis (PCA), was compared with a one-class Support Vector Machine (SVM) model for characterizing the benign executables. We found that the Gaussian model substantially outperformed the one-class SVM in its ability to distinguish malicious from benign files. Complementing to the capabilities in reliably detecting those malicious files with known or similar features using two aforementioned methods, the one-class unsupervised approach may provide another layer of safeguard in identifying those novel computer viruses.

  11. Minimizing deviant behavior in healthcare organizations: the effects of supportive leadership and job design.

    PubMed

    Chullen, C Logan; Dunford, Benjamin B; Angermeier, Ingo; Boss, R Wayne; Boss, Alan D

    2010-01-01

    In an era when healthcare organizations are beset by intense competition, lawsuits, and increased administrative costs, it is essential that employees perform their jobs efficiently and without distraction. Deviant workplace behavior among healthcare employees is especially threatening to organizational effectiveness, and healthcare managers must understand the antecedents of such behavior to minimize its prevalence. Deviant employee behavior has been categorized into two major types, individual and organizational, according to the intended target of the behavior. Behavior directed at the individual includes such acts as harassment and aggression, whereas behavior directed at the organization includes such acts as theft, sabotage, and voluntary absenteeism, to name a few (Robinson and Bennett 1995). Drawing on theory from organizational behavior, we examined two important features of supportive leadership, leader-member exchange (LMX) and perceived organizational support (POS), and two important features of job design, intrinsic motivation and depersonalization, as predictors of subsequent deviant behavior in a sample of over 1,900 employees within a large US healthcare organization. Employees who reported weaker perceptions of LMX and greater perceptions of depersonalization were more likely to engage in deviant behavior directed at the individual, whereas employees who reported weaker perceptions of POS and intrinsic motivation were more likely to engage in deviant behavior directed at the organization. These findings give rise to specific prescriptions for healthcare managers to prevent or minimize the frequency of deviant behavior in the workplace. PMID:21166322

  12. Making MANET secured against malicious attack

    NASA Astrophysics Data System (ADS)

    Kush, Ashwani; Taneja, Sunil; Kush, Shagun

    2011-12-01

    A Mobile Adhoc Network (MANET) is characterized by mobile nodes, multihop wireless connectivity, infrastructureless environment and dynamic topology. A recent trend in Ad Hoc network routing is the reactive ondemand philosophy where routes are established only when required. Stable Routing is of major concern in Ad hoc routing. Security and Power efficiency are the major concerns in this field. This paper is an effort to use security to achieve more reliable routing. The ad hoc environment is accessible to both legitimate network users and malicious attackers. The proposed scheme is intended to incorporate security aspect on existing protocols. The study will help in making protocol more robust against attacks to achieve stable routing in routing protocols.

  13. Mitigation of malicious attacks on networks

    PubMed Central

    Schneider, Christian M.; Moreira, André A.; Andrade, José S.; Havlin, Shlomo; Herrmann, Hans J.

    2011-01-01

    Terrorist attacks on transportation networks have traumatized modern societies. With a single blast, it has become possible to paralyze airline traffic, electric power supply, ground transportation or Internet communication. How and at which cost can one restructure the network such that it will become more robust against a malicious attack? We introduce a new measure for robustness and use it to devise a method to mitigate economically and efficiently this risk. We demonstrate its efficiency on the European electricity system and on the Internet as well as on complex networks models. We show that with small changes in the network structure (low cost) the robustness of diverse networks can be improved dramatically whereas their functionality remains unchanged. Our results are useful not only for improving significantly with low cost the robustness of existing infrastructures but also for designing economically robust network systems. PMID:21368159

  14. Mitigation of malicious attacks on networks.

    PubMed

    Schneider, Christian M; Moreira, André A; Andrade, José S; Havlin, Shlomo; Herrmann, Hans J

    2011-03-01

    Terrorist attacks on transportation networks have traumatized modern societies. With a single blast, it has become possible to paralyze airline traffic, electric power supply, ground transportation or Internet communication. How and at which cost can one restructure the network such that it will become more robust against a malicious attack? We introduce a new measure for robustness and use it to devise a method to mitigate economically and efficiently this risk. We demonstrate its efficiency on the European electricity system and on the Internet as well as on complex networks models. We show that with small changes in the network structure (low cost) the robustness of diverse networks can be improved dramatically whereas their functionality remains unchanged. Our results are useful not only for improving significantly with low cost the robustness of existing infrastructures but also for designing economically robust network systems. PMID:21368159

  15. Mitigation of malicious attacks on network observation

    NASA Astrophysics Data System (ADS)

    Xiao, Yan-Dong; Lao, Song-Yang; Hou, Lv-Lin; Bai, Liang

    2015-02-01

    In the modeling, controlling, and monitoring of complex networks, a fundamental problem concerns the determination and observation of the system's states by using measurements or sensors as few as possible, defined as network observation. This work aims to investigate the robustness of network observation when an approach of minimum dominating set is considered in observing a network. We first investigate the structural properties of the minimum dominating sets, e.g. how the size depends on the degree-degree correlations and how to assess the nodes' importance in the malicious attacks. Then, we introduce a new measurement of robustness for network observation, and implement a hill-climbing algorithm to improve its robustness by edge rewiring. Furthermore, we propose a novel rewiring strategy, called smart rewiring, which could speed up the increment of robustness index. In comparison with previous strategy of edge rewiring, the smart rewiring has been found to be successfully useful on real-world and synthetic networks.

  16. Risk assessment of malicious biocontamination of food.

    PubMed

    Elad, Daniel

    2005-06-01

    Throughout the last decades of the 20th century, the biological threat evolved from primarily a government-controlled weapon to a tool of terrorism. One of the consequences of this trend is the near impossibility of foreseeing when and how an act of bioterrorism will occur. The suitability of food products for such an act stems from the multitude of microorganisms that may be used for contamination and the vulnerability of the products during and after processing. Tests that would enable the detection of a large variety of microorganisms quickly, reliably, and economically should also provide satisfactory means to prevent acts of malicious biocontamination of food products. Until such means become available, a priority-based approach to the problem is probably the most practical. Priorities should be determined based on a systematic risk assessment to define the relative likelihood of a certain microorganism being used in an act of malicious food contamination. Criteria to be evaluated are availability, weaponization processes, delivery of an effective dose, probability of early detection, and the microorganism's resistance to the conditions to which it will be exposed. Because the results of such an assessment may vary according to prevailing conditions, the assessment must be based on the existing circumstances. The results of the assessment should then be applied to the various procedures of food processing, which should further reduce the number of potential microbial threats. Existing methods of screening food for contaminating microorganisms and existing food safety and security procedures such as hazard analysis and critical control point programs may have to be modified to become suitable for the detection of acts of bioterrorism. PMID:15954724

  17. DROP: Detecting Return-Oriented Programming Malicious Code

    NASA Astrophysics Data System (ADS)

    Chen, Ping; Xiao, Hai; Shen, Xiaobin; Yin, Xinchun; Mao, Bing; Xie, Li

    Return-Oriented Programming (ROP) is a new technique that helps the attacker construct malicious code mounted on x86/SPARC executables without any function call at all. Such technique makes the ROP malicious code contain no instruction, which is different from existing attacks. Moreover, it hides the malicious code in benign code. Thus, it circumvents the approaches that prevent control flow diversion outside legitimate regions (such as W ⊕ X ) and most malicious code scanning techniques (such as anti-virus scanners). However, ROP has its own intrinsic feature which is different from normal program design: (1) uses short instruction sequence ending in "ret", which is called gadget, and (2) executes the gadgets contiguously in specific memory space, such as standard GNU libc. Based on the features of the ROP malicious code, in this paper, we present a tool DROP, which is focused on dynamically detecting ROP malicious code. Preliminary experimental results show that DROP can efficiently detect ROP malicious code, and have no false positives and negatives.

  18. Minimizing Bullying Behavior of Middle School Students through Behavioral Intervention and Instruction

    ERIC Educational Resources Information Center

    Drosopoulos, J. Dan; Heald, A. Zachariah; McCue, M. John

    2008-01-01

    This action research project report examined all forms of bullying behaviors and ways to reduce those behaviors. The project included 63 students from both a high school health class and a 6th and 7th grade middle school homeroom. The research was conducted from September 17, 2007 through December 14, 2007. In the specified locations, female to…

  19. Visualizing minimal ingroup and outgroup faces: implications for impressions, attitudes, and behavior.

    PubMed

    Ratner, Kyle G; Dotsch, Ron; Wigboldus, Daniel H J; van Knippenberg, Ad; Amodio, David M

    2014-06-01

    More than 40 years of research have shown that people favor members of their ingroup in their impressions, attitudes, and behaviors. Here, we propose that people also form different mental images of minimal ingroup and outgroup members, and we test the hypothesis that differences in these mental images contribute to the well-established biases that arise from minimal group categorization. In Study 1, participants were assigned to 1 of 2 groups using a classic minimal group paradigm. Next, a reverse correlation image classification procedure was used to create visual renderings of ingroup and outgroup face representations. Subsequently, a 2nd sample naive to the face generation stage rated these faces on a series of trait dimensions. The results indicated that the ingroup face was significantly more likely than the outgroup face to elicit favorable impressions (e.g., trusting, caring, intelligent, attractive). Extending this finding, Study 2 revealed that ingroup face representations elicited more favorable implicitly measured attitudes than did outgroup representations, and Study 3 showed that ingroup faces were trusted more than outgroup faces during an economic game. Finally, Study 4 demonstrated that facial physiognomy associated with trustworthiness more closely resembled the facial structure of the average ingroup than outgroup face representation. Together, these studies suggest that minimal group distinctions can elicit different mental representations, and that this visual bias is sufficient to elicit ingroup favoritism in impressions, attitudes and behaviors. PMID:24841095

  20. Minimization of lumen depreciation in LED lamps using thermal transient behavior analysis and design optimizations.

    PubMed

    Khan, M Nisa

    2016-02-10

    We expansively investigate thermal behaviors of various general-purpose light-emitting diode (LED) lamps and apply our measured results, validated by simulation, to establish lamp design rules for optimizing their optical and thermal properties. These design rules provide the means to minimize lumen depreciation over time by minimizing the periods for lamps to reach thermal steady-state while maintaining their high luminous efficacy and omnidirectional light distribution capability. While it is well known that minimizing the junction temperature of an LED leads to a longer lifetime and an increased lumen output, our study demonstrates, for the first time, to the best of our knowledge, that it is also important to minimize the time it takes to reach thermal equilibrium because doing so minimizes lumen depreciation and enhances light output and color stability during operation. Specifically, we have found that, in addition to inadequate heat-sink fin areas for a lamp configuration, LEDs mounted on multiple boards, as opposed to a single board, lead to longer periods for reaching thermal equilibrium contributing to larger lumen depreciation. PMID:26906393

  1. Clock synchronization of a large multiprocessor system in the presence of malicious faults

    NASA Technical Reports Server (NTRS)

    Shin, Kang G.; Ramanathan, P.

    1987-01-01

    An interconnection algorithm is presented for achieving clock synchronization in a multiprocessor system. The system is assumed to be maliciously faulty, i.e., some processors are out of synchronization and lie about their clock state to other intragroup or intergroup processors. A phase-locked clock network design is proposed which groups the clocks in the system into diverse clusters. The clusters are then treated as single clock units from the perspective of the network. The algorithm minimizes the number of interconnections while permitting synchronization of large multiprocessor systems controlling time-critical applications such as aircraft, nuclear reactors and industrial processes.

  2. Dynamic Malicious Code Detection Based on Binary Translator

    NASA Astrophysics Data System (ADS)

    Fang, Zhe; Li, Minglu; Weng, Chuliang; Luo, Yuan

    The binary translator is a software component of a computer system. It converts binary code of one ISA into binary code of another ISA. Recent trends show that binary translators have been used to save CPU power consumption and CPU die size, which makes binary translators a possible indispensable component of future computer systems. And such situation would give new opportunities to the security of these computer systems. One of the opportunities is that we can perform malicious code checking dynamically in the layer of binary translators. This approach has many advantages, both in terms of capability of detection and checking overhead. In this paper, we proposed a working dynamic malicious code checking module integrated to an existent open-source binary translator, QEMU, and explained that our module's capability of detection is superior to other malicious code checking methods while acceptable performance is still maintained.

  3. Phantom behavior bounce with tachyon and non-minimal derivative coupling

    SciTech Connect

    Banijamali, A.; Fazlpour, B. E-mail: b.fazlpour@umz.ac.ir

    2012-01-01

    The bouncing cosmology provides a successful solution of the cosmological singularity problem. In this paper, we study the bouncing behavior of a single scalar field model with tachyon field non-minimally coupled to itself, its derivative and to the curvature. By utilizing the numerical calculations we will show that the bouncing solution can appear in the universe dominated by such a quintom matter with equation of state crossing the phantom divide line. We also investigate the classical stability of our model using the phase velocity of the homogeneous perturbations of the tachyon scalar field.

  4. Collision-avoidance behaviors of minimally restrained flying locusts to looming stimuli

    PubMed Central

    Chan, R. WM.; Gabbiani, F.

    2013-01-01

    SUMMARY Visually guided collision avoidance is of paramount importance in flight, for instance to allow escape from potential predators. Yet, little is known about the types of collision-avoidance behaviors that may be generated by flying animals in response to an impending visual threat. We studied the behavior of minimally restrained locusts flying in a wind tunnel as they were subjected to looming stimuli presented to the side of the animal, simulating the approach of an object on a collision course. Using high-speed movie recordings, we observed a wide variety of collision-avoidance behaviors including climbs and dives away from – but also towards – the stimulus. In a more restrained setting, we were able to relate kinematic parameters of the flapping wings with yaw changes in the trajectory of the animal. Asymmetric wing flapping was most strongly correlated with changes in yaw, but we also observed a substantial effect of wing deformations. Additionally, the effect of wing deformations on yaw was relatively independent of that of wing asymmetries. Thus, flying locusts exhibit a rich range of collision-avoidance behaviors that depend on several distinct aerodynamic characteristics of wing flapping flight. PMID:23364572

  5. The Use of Behavioral Agreements by Senior Student Affairs Officers and Counseling Center Directors to Manage Student Mental Health Concerns and Minimize Threatening Behavior

    ERIC Educational Resources Information Center

    Geiger, Douglas

    2010-01-01

    This qualitative investigation examines the use of behavioral agreements by Senior Student Affairs Officers and Counseling Center Directors to manage student mental health concerns and minimize behavior that poses threats to campus communities. Six pairs of Senior Student Affairs Officers and Counseling Center Directors at the same institution…

  6. Maintain the structural controllability under malicious attacks on directed networks

    NASA Astrophysics Data System (ADS)

    Wang, Bingbo; Gao, Lin; Gao, Yong; Deng, Yue

    2013-03-01

    The directedness of the links in a network plays a critical role in determining many dynamical processes among which the controllability has received much recent attention. The control robustness of a network against malicious attack and random failure also becomes a significant issue. In this paper, we propose a novel control robustness index motivated by recent studies on the global connectivity and controllability. In its general form, the problem of optimizing the control robustness index is computationally infeasible for large-scale networks. By analysing the influences of several directed topological factors on the dynamical control process, we transform the control robustness problem into the problem of transitivity maximization for control routes, and propose an efficient greedy algorithm to make control routes transitive. A series of experiments on real-world and synthetic networks show that the global connectivity and controllability can be improved simultaneously and we can mitigate the destruction of malicious attack through backing up the control routes.

  7. Transient hepatomegaly and hypoglycemia. A consequence of malicious insulin administration.

    PubMed

    Dershewitz, R; Vestal, B; Maclaren, N K; Cornblath, M

    1976-09-01

    On two occasions, a 3 1/2-year-old black girl had severe hypoglycemia associated with transient hepatomegaly. The plasma insulin level during the second hypoglycemic episode was excessive and led to a diagnosis of malicious insulin administration. We suggest that plasma be obtained for insulin determination in children with hypoglycemia, and that transient hepatomegaly may be a helpful sign in cases of insulin overdose. PMID:961662

  8. Absence of physician recourse in malpractice litigation--malicious prosecution.

    PubMed

    Spector, Richard A

    2002-01-01

    The courts are protective of the plaintiff's rights under law to seek redress in the court by placing the facts of their allegations before a judge or jury. Because the avenue to the court is through representation and advocacy, the courts equally are protective of the agent of that representation, the attorney. To date, no physician who has been sued for medical malpractice in Louisiana has brought a successful malicious prosecution claim against the plaintiff or his attorney. PMID:12014457

  9. Neurophysiological and Behavioral Responses to Music Therapy in Vegetative and Minimally Conscious States

    PubMed Central

    O’Kelly, Julian; James, L.; Palaniappan, R.; Taborin, J.; Fachner, J.; Magee, W. L.

    2013-01-01

    Assessment of awareness for those with disorders of consciousness is a challenging undertaking, due to the complex presentation of the population. Debate surrounds whether behavioral assessments provide greatest accuracy in diagnosis compared to neuro-imaging methods, and despite developments in both, misdiagnosis rates remain high. Music therapy may be effective in the assessment and rehabilitation with this population due to effects of musical stimuli on arousal, attention, and emotion, irrespective of verbal or motor deficits. However, an evidence base is lacking as to which procedures are most effective. To address this, a neurophysiological and behavioral study was undertaken comparing electroencephalogram (EEG), heart rate variability, respiration, and behavioral responses of 20 healthy subjects with 21 individuals in vegetative or minimally conscious states (VS or MCS). Subjects were presented with live preferred music and improvised music entrained to respiration (procedures typically used in music therapy), recordings of disliked music, white noise, and silence. ANOVA tests indicated a range of significant responses (p ≤ 0.05) across healthy subjects corresponding to arousal and attention in response to preferred music including concurrent increases in respiration rate with globally enhanced EEG power spectra responses (p = 0.05–0.0001) across frequency bandwidths. Whilst physiological responses were heterogeneous across patient cohorts, significant post hoc EEG amplitude increases for stimuli associated with preferred music were found for frontal midline theta in six VS and four MCS subjects, and frontal alpha in three VS and four MCS subjects (p = 0.05–0.0001). Furthermore, behavioral data showed a significantly increased blink rate for preferred music (p = 0.029) within the VS cohort. Two VS cases are presented with concurrent changes (p ≤ 0.05) across measures indicative of discriminatory responses to both music therapy

  10. Price-Minimizing Behaviors in a Cohort of Smokers before and after a Cigarette Tax Increase

    PubMed Central

    Betzner, Anne; Boyle, Raymond G.; St. Claire, Ann W.

    2016-01-01

    Cigarette tax increases result in a reduced demand for cigarettes and increased efforts by smokers to reduce their cost of smoking. Less is known about how smokers think about their expenditures for cigarettes and the possible mechanisms that underlie price-minimizing behaviors. In-depth longitudinal interviews were conducted with Minnesota smokers to explore the factors that influence smokers’ decisions one month prior to a $1.75 cigarette tax increase and again one and three months after the increase. A total of 42 were sampled with 35 completed interviews at all three time points, resulting in 106 interviews across all participants at all time points. A qualitative descriptive approach examined smoking and buying habits, as well as reasons behind these decisions. A hierarchy of ways to save money on cigarettes included saving the most money by changing to roll your own pipe tobacco, changing to a cheaper brand, cutting down or quitting, changing to cigarillos, and buying online. Using coupons, shopping around, buying by the carton, changing the style of cigarette, and stocking up prior to the tax increase were described as less effective. Five factors emerged as impacting smokers’ efforts to save money on cigarettes after the tax: brand loyalty, frugality, addiction, stress, and acclimation. PMID:27322301

  11. Price-Minimizing Behaviors in a Cohort of Smokers before and after a Cigarette Tax Increase.

    PubMed

    Betzner, Anne; Boyle, Raymond G; St Claire, Ann W

    2016-01-01

    Cigarette tax increases result in a reduced demand for cigarettes and increased efforts by smokers to reduce their cost of smoking. Less is known about how smokers think about their expenditures for cigarettes and the possible mechanisms that underlie price-minimizing behaviors. In-depth longitudinal interviews were conducted with Minnesota smokers to explore the factors that influence smokers' decisions one month prior to a $1.75 cigarette tax increase and again one and three months after the increase. A total of 42 were sampled with 35 completed interviews at all three time points, resulting in 106 interviews across all participants at all time points. A qualitative descriptive approach examined smoking and buying habits, as well as reasons behind these decisions. A hierarchy of ways to save money on cigarettes included saving the most money by changing to roll your own pipe tobacco, changing to a cheaper brand, cutting down or quitting, changing to cigarillos, and buying online. Using coupons, shopping around, buying by the carton, changing the style of cigarette, and stocking up prior to the tax increase were described as less effective. Five factors emerged as impacting smokers' efforts to save money on cigarettes after the tax: brand loyalty, frugality, addiction, stress, and acclimation. PMID:27322301

  12. How do price minimizing behaviors impact smoking cessation? Findings from the International Tobacco Control (ITC) Four Country Survey.

    PubMed

    Licht, Andrea S; Hyland, Andrew J; O'Connor, Richard J; Chaloupka, Frank J; Borland, Ron; Fong, Geoffrey T; Nargis, Nigar; Cummings, K Michael

    2011-05-01

    This paper examines how price minimizing behaviors impact efforts to stop smoking. Data on 4,988 participants from the International Tobacco Control Policy Evaluation (ITC) Four-Country Survey who were smokers at baseline (wave 5) and interviewed at a 1 year follow-up were used. We examined whether price minimizing behaviors at baseline predicted: (1) cessation, (2) quit attempts, and (3) successful quit attempts at one year follow up using multivariate logistic regression modeling. A subset analysis included 3,387 participants who were current smokers at waves 5 and 6 and were followed through wave 7 to explore effects of changing purchase patterns on cessation. Statistical tests for interaction were performed to examine the joint effect of SES and price/tax avoidance behaviors on cessation outcomes. Smokers who engaged in any price/tax avoidance behaviors were 28% less likely to report cessation. Persons using low/untaxed sources were less likely to quit at follow up, those purchasing cartons were less likely to make quit attempts and quit, and those using discount cigarettes were less likely to succeed, conditional on making attempts. Respondents who utilized multiple behaviors simultaneously were less likely to make quit attempts and to succeed. SES did not modify the effects of price minimizing behaviors on cessation outcomes. The data from this paper indicate that the availability of lower priced cigarette alternatives may attenuate public health efforts aimed at to reduce reducing smoking prevalence through price and tax increases among all SES groups. PMID:21655144

  13. Assisting People with Multiple Disabilities and Minimal Motor Behavior to Control Environmental Stimulation through a Mouse Wheel

    ERIC Educational Resources Information Center

    Shih, Ching-Hsiang; Shih, Ching-Tien; Lin, Kun-Tsan; Chiang, Ming-Shan

    2009-01-01

    This study assessed whether two people with profound multiple disabilities and minimal motor behavior would be able to control environmental stimulation using thumb poke ability with a mouse wheel and a newly developed mouse driver (i.e., a new mouse driver replacing standard mouse driver, and turning a mouse into a precise thumb poke detector).…

  14. Assisting People with Multiple Disabilities and Minimal Motor Behavior to Improve Computer Pointing Efficiency through a Mouse Wheel

    ERIC Educational Resources Information Center

    Shih, Ching-Hsiang; Chang, Man-Ling; Shih, Ching-Tien

    2009-01-01

    This study evaluated whether two people with multiple disabilities and minimal motor behavior would be able to improve their pointing performance using finger poke ability with a mouse wheel through a Dynamic Pointing Assistive Program (DPAP) and a newly developed mouse driver (i.e., a new mouse driver replaces standard mouse driver, changes a…

  15. Children with Multiple Disabilities and Minimal Motor Behavior Using Chin Movements to Operate Microswitches to Obtain Environmental Stimulation

    ERIC Educational Resources Information Center

    Lancioni, Giulio E.; O'Reilly, Mark F.; Singh, Nirbhay N.; Sigafoos, Jeff; Tota, Alessia; Antonucci, Massimo; Oliva, Doretta

    2006-01-01

    In these two studies, two children with multiple disabilities and minimal motor behavior were assessed to see if they could use chin movements to operate microswitches to obtain environmental stimulation. In Study I, we applied an adapted version of a recently introduced electronic microswitch [Lancioni, G. E., O'Reilly, M. F., Singh, N. N.,…

  16. An Overview of Intervention Options for Promoting Adaptive Behavior of Persons with Acquired Brain Injury and Minimally Conscious State

    ERIC Educational Resources Information Center

    Lancioni, Giulio E.; Bosco, Andrea; Belardinelli, Marta Olivetti; Singh, Nirbhay N.; O'Reilly, Mark F.; Sigafoos, Jeff

    2010-01-01

    This paper presents an overview of the studies directed at helping post-coma persons with minimally conscious state improve their adaptive behavior. Twenty-one studies were identified for the 2000-2010 period (i.e., a period in which an intense debate has occurred about diagnostic, rehabilitative, prognostic, and ethical issues concerning people…

  17. Minimizing liability during internal investigations.

    PubMed

    Morris, Cole

    2010-01-01

    Today's security professional must appreciate the potential landmines in any investigative effort and work collaboratively with others to minimize liability risks, the author points out. In this article he examines six civil torts that commonly arise from unprofessionally planned or poorly executed internal investigations-defamation, false imprisonment. intentional infliction of emotional distress, assault and battery, invasion of privacy, and malicious prosecution and abuse of process. PMID:20873494

  18. Onion-like network topology enhances robustness against malicious attacks

    NASA Astrophysics Data System (ADS)

    Herrmann, Hans J.; Schneider, Christian M.; Moreira, André A.; Andrade, José S., Jr.; Havlin, Shlomo

    2011-01-01

    We develop a method to generate robust networks against malicious attacks, as well as to substantially improve the robustness of a given network by swapping edges and keeping the degree distribution fixed. The method, based on persistence of the size of the largest cluster during attacks, was applied to several types of networks with broad degree distributions, including a real network—the Internet. We find that our method can improve the robustness significantly. Our results show that robust networks have a novel 'onion-like' topology consisting of a core of highly connected nodes hierarchically surrounded by rings of nodes with decreasing degree.

  19. Monitoring and Diagnosing Malicious Attacks with Autonomic Software

    NASA Astrophysics Data System (ADS)

    Souza, Vítor E. Silva; Mylopoulos, John

    Monitoring and diagnosing (M&D) software based on requirement models is a problem that has recently received a lot of attention in field of Requirement Engineering. In this context, Wang et al. [1] propose a M&D framework that uses goal models to diagnose failures in software at different levels of granularity. In this paper we extend Wang's framework to monitor and diagnose malicious attacks. Our extensions include the addition of anti-goals to model attacker intentions, as well as context-based modeling of the domain within which our system operates. The extended framework has been implemented and evaluated through a series of experiments intended to test its scalability.

  20. Quantum private comparison with a malicious third party

    NASA Astrophysics Data System (ADS)

    Sun, Zhiwei; Yu, Jianping; Wang, Ping; Xu, Lingling; Wu, Chunhui

    2015-06-01

    In this paper, we will show that quantum private comparison protocol is secure when a malicious third party is presented. The security of the protocol is considered in a cheat-sensitive model, in which the TP is kept honest by the possibility of being caught cheating. Besides, we enhance the privacy of the quantum private comparison protocol, where the participants' inputs and the comparison result can be preserved. Furthermore, in contrast to pervious protocols requiring a large amount of quantum resources, such as entanglement and quantum memory, our protocol is based on BB84 protocol, which is more feasible for practical applications. Finally, we analyze the security of the presented protocol.

  1. Malicious attacks on media authentication schemes based on invertible watermarks

    NASA Astrophysics Data System (ADS)

    Katzenbeisser, Stefan; Dittmann, Jana

    2004-06-01

    The increasing availability and distribution of multimedia technology has made the manipulation of digital images, videos or audio files easy. While this enables numerous new applications, a certain loss of trust in digital media can be observed. In general, there is no guarantee that a digital image "does not lie", i.e., that the image content was not altered. To counteract this risk, fragile watermarks were proposed to protect the integrity of digital multimedia objects. In high security applications, it is necessary to be able to reconstruct the original object out of the watermarked version. This can be achieved by the use of invertible watermarks. While traditional watermarking schemes introduce some small non-invertible distortion in the digital content, invertible watermarks can be completely removed from a watermarked work. In the past, the security of proposed image authentication schemes based on invertible watermarks was only analyzed using ad-hoc methods and neglected the possibility of malicious attacks, which aim at engineering a fake mark so that the attacked object appears to be genuine. In this paper, we characterize and analyze possible malicious attacks against watermark-based image authentication systems and explore the theoretical limits of previous constructions with respect to their security.

  2. Malicious node detection in ad-hoc wireless networks

    NASA Astrophysics Data System (ADS)

    Griswold, Richard L.; Medidi, Sirisha R.

    2003-07-01

    Advances in wireless communications and the proliferation of mobile computing devices has led to the rise of a new type of computer network: the ad-hoc wireless network. Ad-hoc networks are characterized by a lack of fixed infrastructure, which give ad-hoc networks a great deal of flexibility, but also increases the risk of security problems. In wired networks, key pieces of network infrastructure are secured to prevent unauthorized physical access and tampering. Network administrators ensure that everything is properly configured and are on-hand to fix problems and deal with intrusions. In contrast, the nodes in an ad-hoc network are responsible for routing and forwarding data in the network, and there are no network administrators to handle potential problems. This makes an ad-hoc network more vulnerable to a misconfigured, faulty, or compromised node. We propose a means for a node in an ad-hoc network to detect and handle these malicious nodes by comparing data available to the routing protocol, such as cached routes in Dynamic Source Routing, ICMP messages, and transport layer information, such as TCP timeouts. This data can then be used along with network probes to isolate the malicious node.

  3. Eating disorder behaviors and depression: a minimal relationship beyond social comparison, self-esteem, and body dissatisfaction.

    PubMed

    Green, Melinda A; Scott, Norman A; Cross, Susan E; Liao, Kelly Yu-Hsin; Hallengren, Jada J; Davids, Christopher M; Carter, Lindsey P; Kugler, David W; Read, Katherine E; Jepson, Amanda J

    2009-09-01

    Existing literature fails to comprehensively identify factors contributing to the comorbid relationship between eating disorder (ED) behaviors and unipolar depression. Maladaptive social comparison, body dissatisfaction, and low self-esteem are disruptive psychological patterns common to both constructs. It is unclear whether a unique relationship exists between depression and eating disorder behaviors beyond the effects exerted by this negative cognitive triad. The purpose of the present study is to examine whether a unique relationship exists between depression and ED behaviors after controlling for maladaptive social comparison, body dissatisfaction, and low self-esteem. We predict minimal unique variance in ED behaviors will be explained by depression after controlling for this negative cognitive triad. PMID:19388056

  4. Malicious pleasure: schadenfreude at the suffering of another group.

    PubMed

    Leach, Colin Wayne; Spears, Russell; Branscombe, Nyla R; Doosje, Bertjan

    2003-05-01

    Two studies examined intergroup schadenfreude--malicious pleasure at an out-group's misfortune. Study 1 showed that schadenfreude regarding a German loss in soccer was increased by interest in soccer and threats of Dutch inferiority. The effect of inferiority threat was especially strong for participants less interested in soccer; the more interested showed relatively high schadenfreude. Study 2 replicated these effects by showing a similar pattern of schadenfreude regarding losses by Germany and Italy in another setting. However, schadenfreude toward legitimately superior Italy was lower when a norm of honest and direct expression was made salient to participants lower in soccer interest. These results establish schadenfreude as an emotion that is moderated by the salient dimensions of particular intergroup relations. PMID:12757139

  5. Optimization of robustness of network controllability against malicious attacks

    NASA Astrophysics Data System (ADS)

    Xiao, Yan-Dong; Lao, Song-Yang; Hou, Lv-Lin; Bai, Liang

    2014-11-01

    As the controllability of complex networks has attracted much attention recently, how to design and optimize the robustness of network controllability has become a common and urgent problem in the engineering field. In this work, we propose a method that modifies any given network with strict structural perturbation to effectively enhance its robustness against malicious attacks, called dynamic optimization of controllability. Unlike other structural perturbations, the strict perturbation only swaps the links and keeps the in- and out-degree unchanged. A series of extensive experiments show that the robustness of controllability and connectivity can be improved dramatically. Furthermore, the effectiveness of our method is explained from the views of underlying structure. The analysis results indicate that the optimization algorithm makes networks more homogenous and assortative.

  6. Protecting software agents from malicious hosts using quantum computing

    NASA Astrophysics Data System (ADS)

    Reisner, John; Donkor, Eric

    2000-07-01

    We evaluate how quantum computing can be applied to security problems for software agents. Agent-based computing, which merges technological advances in artificial intelligence and mobile computing, is a rapidly growing domain, especially in applications such as electronic commerce, network management, information retrieval, and mission planning. System security is one of the more eminent research areas in agent-based computing, and the specific problem of protecting a mobile agent from a potentially hostile host is one of the most difficult of these challenges. In this work, we describe our agent model, and discuss the capabilities and limitations of classical solutions to the malicious host problem. Quantum computing may be extremely helpful in addressing the limitations of classical solutions to this problem. This paper highlights some of the areas where quantum computing could be applied to agent security.

  7. A Study on Architecture of Malicious Code Blocking Scheme with White List in Smartphone Environment

    NASA Astrophysics Data System (ADS)

    Lee, Kijeong; Tolentino, Randy S.; Park, Gil-Cheol; Kim, Yong-Tae

    Recently, the interest and demands for mobile communications are growing so fast because of the increasing prevalence of smartphones around the world. In addition, the existing feature phones were replaced by smartphones and it has widely improved while using the explosive growth of Internet users using smartphones, e-commerce enabled Internet banking transactions and the importance of protecting personal information. Therefore, the development of smartphones antivirus products was developed and launched in order to prevent malicious code or virus infection. In this paper, we proposed a new scheme to protect the smartphone from malicious codes and malicious applications that are element of security threats in mobile environment and to prevent information leakage from malicious code infection. The proposed scheme is based on the white list smartphone application which only allows installing authorized applications and to prevent the installation of malicious and untrusted mobile applications which can possibly infect the applications and programs of smartphones.

  8. An Original Behavior Modification Program for Weight Reduction: Minimal Intervention and Permanent Habit Change.

    ERIC Educational Resources Information Center

    Lublin, Irwin; Kirkish, Patricia

    This description of a weight reduction program, based on generalizations derived from eight years of work with overweight persons, discusses the clients' rationalization of overeating behaviors. In this behavior modification program, the client is required to permanently give up one high calorie food and to write down all foods eaten before actual…

  9. Web Canary: A Virtualized Web Browser to Support Large-Scale Silent Collaboration in Detecting Malicious Web Sites

    NASA Astrophysics Data System (ADS)

    Wang, Jiang; Ghosh, Anup; Huang, Yih

    Malicious Web content poses a serious threat to the Internet, organizations and users. Current approaches to detecting malicious Web content employ high-powered honey clients to scan the Web for potentially malicious pages. These approaches, while effective at detecting malicious content, have the drawbacks of being few and far between, presenting a single snapshot in time of very dynamic phenomena, and having artificial test data. To address these problems, we developed a virtualized Web browser that uses large-scale collaboration to identify URLs that host malicious content on a continuing basis by building in an elective reporting system. The system, which we call a Web canary, runs a standard Web browser in a known, pristine OS every time the browser starts. Users not only report malicious URLs but also benefit from protection against malicious content. Experimental results show that it can detect the malicious Web pages effectively with acceptable overhead.

  10. MIS-behavior: practical heuristics for precise pediatric minimally invasive surgery.

    PubMed

    Blinman, Thane A

    2015-02-01

    Minimally invasive surgery (MIS) has changed pediatric urology and general surgery, offering less morbidity and new surgical options for many procedures. This promise goes unrealized when technical methods lag. Application of MIS in children is uneven after more than 2 decades of application. Principles of versatile and proficient technique may remain unstated and implicit in surgical training, often leaving surgical training an exercise in inference and imitation. This article describes some essential practical principles of precision MIS applied to patients of any size. PMID:25455179

  11. Minimal changes in hypothalamic temperature accompany microwave-induced alteration of thermoregulatory behavior

    SciTech Connect

    Adair, E.R.; Adams, B.W.; Akel, G.M.

    1984-01-01

    This study probed the mechanisms underlying microwave-induced alterations of thermoregulatory behavior. Adult male squirrel monkeys (Saimiri sciureus), trained to regulate the temperature of their immediate environment (Ta) behaviorally, were chronically implanted with Teflon reentrant tubes in the medical preoptic/anterior hypothalamic area (PO/AH), the brainstem region considered to control normal thermoregulatory processes. A Vitek temperature probe inserted into the tube measured PO/AH temperature continuously while changes in thermoregulatory behavior were induced by either brief (10-min) or prolonged (2.5-h) unilateral exposures to planewave 2,450-MHz continuous wave (CW) microwaves (E polarization). Power densities explored ranged from 4 to 20 mW/cm2 (rate of energy absorption (SAR) . 0.05 (W/kg)/cm2)). Rectal temperature and four representative skin temperatures were also monitored, as was the Ta selected by the animal. When the power density was high enough to induce a monkey to select a cooler Ta (8 mW/cm2 and above), PO/AH temperature rose approximately 0.3 degrees C but seldom more. Lower power densities usually produced smaller increases in PO/AH temperature and no reliable change in thermoregulatory behavior. Rectal temperature remained constant while PO/AH temperature rose only 0.2-0.3 degrees C during 2.5-h exposures at 20 mW/cm2 because the Ta selected was 2-3 degrees C cooler than normally preferred. Sometimes PO/AH temperature increments greater than 0.3 degrees C were recorded, but they always accompanied inadequate thermoregulatory behavior. Thus, a PO/AH temperature rise of 0.2-0.3 degrees C, accompanying microwave exposure, appears to be necessary and sufficient to alter thermoregulatory behavior, which ensures in turn that no greater temperature excursions occur in this hypothalamic thermoregulatory center.

  12. Cognitive behavioral therapy and exercise minimally help Gulf War veterans' illnesses.

    PubMed

    Luttermoser, Gary

    2003-06-01

    Cognitive behavioral therapy and aerobic exercise provide only modest relief from symptoms of Gulf War veterans' illnesses. Unfortunately, over 80% of the patients showed no improvement of symptoms after 1 year of either or both treatments. With the Iraqi war ending, the outcomes of veterans of this previous conflict may prove significant. PMID:12791222

  13. IDMA: improving the defense against malicious attack for mobile ad hoc networks based on ARIP protocol

    NASA Astrophysics Data System (ADS)

    Peng, Chaorong; Chen, Chang Wen

    2008-04-01

    Malicious nodes are mounting increasingly sophisticated attacking operations on the Mobile Ad Hoc Networks (MANETs). This is mainly because the IP-based MANETs are vulnerable to attacks by various malicious nodes. However, the defense against malicious attack can be improved when a new layer of network architecture can be developed to separate true IP address from disclosing to the malicious nodes. In this paper, we propose a new algorithm to improve the defense against malicious attack (IDMA) that is based on a recently developed Assignment Router Identify Protocol (ARIP) for the clustering-based MANET management. In the ARIP protocol, we design the ARIP architecture based on the new Identity instead of the vulnerable IP addresses to provide the required security that is embedded seamlessly into the overall network architecture. We make full use of ARIP's special property to monitor gateway forward packets by Reply Request Route Packets (RREP) without additional intrusion detection layer. We name this new algorithm IDMA because of its inherent capability to improve the defense against malicious attacks. Through IDMA, a watching algorithm can be established so as to counterattack the malicious node in the routing path when it unusually drops up packets. We provide analysis examples for IDMA for the defense against a malicious node that disrupts the route discovery by impersonating the destination, or by responding with state of corrupted routing information, or by disseminating forged control traffic. The IDMA algorithm is able to counterattack the malicious node in the cases when the node lunch DoS attack by broadcast a large number of route requests, or make Target traffic congestion by delivering huge mount of data; or spoof the IP addresses and send forge packets with a fake ID to the same Target causing traffic congestion at that destination. We have implemented IDMA algorism using the GloMoSim simulator and have demonstrated its performance under a variety of

  14. Parsing (malicious) pleasures: schadenfreude and gloating at others' adversity.

    PubMed

    Leach, Colin Wayne; Spears, Russell; Manstead, Antony S R

    2015-01-01

    We offer the first empirical comparison of the pleasure in seeing (i.e., schadenfreude) and in causing (i.e., gloating) others' adversity. In Study 1, we asked participants to recall and report on an (individual or group) episode of pleasure that conformed to our formal definition of schadenfreude, gloating, pride, or joy, without reference to an emotion word. Schadenfreude and gloating were distinct in the situational features of the episode, participants' appraisals of it, and their expressions of pleasure (e.g., smiling, boasting). In Study 2, we had participants imagine being in an (individual or group) emotion episode designed to fit our conceptualization of schadenfreude or gloating. Individual and group versions of the emotions did not differ much in either study. However, the two pleasures differed greatly in their situational features, appraisals, experience, and expression. This parsing of the particular pleasures of schadenfreude and gloating brings nuance to the study of (malicious) pleasure, which tends to be less finely conceptualized and examined than displeasure despite its importance to social relations. PMID:25767455

  15. Audio watermarking forensics: detecting malicious re-embedding

    NASA Astrophysics Data System (ADS)

    Zmudzinski, Sascha; Steinebach, Martin; Katzenbeisser, Stefan; Rührmair, Ulrich

    2010-01-01

    Digital watermarking has become a widely used security technology in the domain of digital rights management and copyright protection as well as in other applications. In this work, we show recent results regarding a particular security attack: Embedding a new message in a previously watermarked cover using the same key as the original message. This re-embedding can be the consequence of the absence of truly asymmetric watermarking solutions, especially if the watermark is to be detected in public. In public detection scenarios, every detector needs the same key the embedder used to watermark the cover. With knowledge of the embedding algorithm, everybody who is able to detect the message can also maliciously embed a new message with the same key over the old one. This scenario is relevant in the case that an attacker intends to counterfeit a copyright notice, transaction ID or to change an embedded authentication code. This work presents experimental results on mechanisms for identifying such multiple embeddings in a spreadspectrum patchwork audio watermarking approach. We demonstrate that under certain circumstances such multiple embedding can be detected by watermarking-forensics.

  16. Parsing (malicious) pleasures: schadenfreude and gloating at others’ adversity

    PubMed Central

    Leach, Colin Wayne; Spears, Russell; Manstead, Antony S. R.

    2015-01-01

    We offer the first empirical comparison of the pleasure in seeing (i.e., schadenfreude) and in causing (i.e., gloating) others’ adversity. In Study 1, we asked participants to recall and report on an (individual or group) episode of pleasure that conformed to our formal definition of schadenfreude, gloating, pride, or joy, without reference to an emotion word. Schadenfreude and gloating were distinct in the situational features of the episode, participants’ appraisals of it, and their expressions of pleasure (e.g., smiling, boasting). In Study 2, we had participants imagine being in an (individual or group) emotion episode designed to fit our conceptualization of schadenfreude or gloating. Individual and group versions of the emotions did not differ much in either study. However, the two pleasures differed greatly in their situational features, appraisals, experience, and expression. This parsing of the particular pleasures of schadenfreude and gloating brings nuance to the study of (malicious) pleasure, which tends to be less finely conceptualized and examined than displeasure despite its importance to social relations. PMID:25767455

  17. Energy barriers, entropy barriers, and non-Arrhenius behavior in a minimal glassy model

    NASA Astrophysics Data System (ADS)

    Du, Xin; Weeks, Eric R.

    2016-06-01

    We study glassy dynamics using a simulation of three soft Brownian particles confined to a two-dimensional circular region. If the circular region is large, the disks freely rearrange, but rearrangements are rarer for smaller system sizes. We directly measure a one-dimensional free-energy landscape characterizing the dynamics. This landscape has two local minima corresponding to the two distinct disk configurations, separated by a free-energy barrier that governs the rearrangement rate. We study several different interaction potentials and demonstrate that the free-energy barrier is composed of a potential-energy barrier and an entropic barrier. The heights of both of these barriers depend on temperature and system size, demonstrating how non-Arrhenius behavior can arise close to the glass transition.

  18. An Efficient Protocol for Secure Two-Party Computation in the Presence of Malicious Adversaries

    NASA Astrophysics Data System (ADS)

    Lindell, Yehuda; Pinkas, Benny

    We show an efficient secure two-party protocol, based on Yao's construction, which provides security against malicious adversaries. Yao's original protocol is only secure in the presence of semi-honest adversaries. Security against malicious adversaries can be obtained by applying the compiler of Goldreich, Micali and Wigderson (the "GMW compiler"). However, this approach does not seem to be very practical as it requires using generic zero-knowledge proofs.

  19. A provably secure revocable ID-based authenticated group key exchange protocol with identifying malicious participants.

    PubMed

    Wu, Tsu-Yang; Tsai, Tung-Tso; Tseng, Yuh-Min

    2014-01-01

    The existence of malicious participants is a major threat for authenticated group key exchange (AGKE) protocols. Typically, there are two detecting ways (passive and active) to resist malicious participants in AGKE protocols. In 2012, the revocable identity- (ID-) based public key system (R-IDPKS) was proposed to solve the revocation problem in the ID-based public key system (IDPKS). Afterwards, based on the R-IDPKS, Wu et al. proposed a revocable ID-based AGKE (RID-AGKE) protocol, which adopted a passive detecting way to resist malicious participants. However, it needs three rounds and cannot identify malicious participants. In this paper, we fuse a noninteractive confirmed computation technique to propose the first two-round RID-AGKE protocol with identifying malicious participants, which is an active detecting way. We demonstrate that our protocol is a provably secure AGKE protocol with forward secrecy and can identify malicious participants. When compared with the recently proposed ID/RID-AGKE protocols, our protocol possesses better performance and more robust security properties. PMID:24991641

  20. A Provably Secure Revocable ID-Based Authenticated Group Key Exchange Protocol with Identifying Malicious Participants

    PubMed Central

    Tsai, Tung-Tso

    2014-01-01

    The existence of malicious participants is a major threat for authenticated group key exchange (AGKE) protocols. Typically, there are two detecting ways (passive and active) to resist malicious participants in AGKE protocols. In 2012, the revocable identity- (ID-) based public key system (R-IDPKS) was proposed to solve the revocation problem in the ID-based public key system (IDPKS). Afterwards, based on the R-IDPKS, Wu et al. proposed a revocable ID-based AGKE (RID-AGKE) protocol, which adopted a passive detecting way to resist malicious participants. However, it needs three rounds and cannot identify malicious participants. In this paper, we fuse a noninteractive confirmed computation technique to propose the first two-round RID-AGKE protocol with identifying malicious participants, which is an active detecting way. We demonstrate that our protocol is a provably secure AGKE protocol with forward secrecy and can identify malicious participants. When compared with the recently proposed ID/RID-AGKE protocols, our protocol possesses better performance and more robust security properties. PMID:24991641

  1. Evil acts and malicious gossip: a multiagent model of the effects of gossip in socially distributed person perception.

    PubMed

    Smith, Eliot R

    2014-11-01

    Although person perception is central to virtually all human social behavior, it is ordinarily studied in isolated individual perceivers. Conceptualizing it as a socially distributed process opens up a variety of novel issues, which have been addressed in scattered literatures mostly outside of social psychology. This article examines some of these issues using a series of multiagent models. Perceivers can use gossip (information from others about social targets) to improve their ability to detect targets who perform rare negative behaviors. The model suggests that they can simultaneously protect themselves against being influenced by malicious gossip intended to defame specific targets. They can balance these potentially conflicting goals by using specific strategies including disregarding gossip that differs from a personally obtained impression. Multiagent modeling demonstrates the outcomes produced by different combinations of assumptions about gossip, and suggests directions for further research and theoretical development. PMID:24727973

  2. Justifying the need for forensically ready protocols: A case study of identifying malicious web servers using client honeypots

    SciTech Connect

    Seifert, Christian; Endicott-Popovsky, Barbara E.; Frincke, Deborah A.; Komisarczuk, Peter; Muschevici, Radu; Welch, Ian D.

    2008-01-03

    Abstract: Client honeypot technology can find malicious web servers that attack web browsers and push malware, so called drive-by-downloads, to the client machine. Merely recording the network traffic is insufficient to perform an efficient forensic analysis of the attack. Custom tools need to be developed to access and examine the embedded data of the network protocols. Once the information is extracted from the network data, it cannot be used to perform a behavioral analysis on the attack, therefore limiting the ability to answer what exactly happened on the attacked system. Implementation of a record/ replay mechanism is proposed that allows the forensic examiner to easily extract application data from recorded network streams and allows applications to interact with such data for behavioral analysis purposes. A concrete implementation of such a setup for HTTP and DNS protocols using the HTTP proxy Squid and DNS proxy pdnsd is presented and its effect on digital forensic analysis demonstrated.

  3. Self-help cognitive-behavioral therapy with minimal therapist contact for social phobia: a controlled trial.

    PubMed

    Abramowitz, Jonathan S; Moore, Elizabeth L; Braddock, Autumn E; Harrington, Diana L

    2009-03-01

    Due to treatment accessibility and cost issues, interest in self-help programs (e.g., bibliotherapy, telehealth) for common psychological disorders is growing. Research supporting the efficacy of such a program for social anxiety, however, is limited. The present study examined the efficacy of an 8-week self-directed cognitive behavioral treatment with minimal therapist involvement for social phobia based on a widely available self-help book. Twenty-one adults with social phobia initially received either treatment (i.e. assigned readings in the workbook with limited therapist contact) or were wait-listed. Wait-listed patients eventually received the same self-directed treatment. Results revealed that the self-help/minimal therapist contact treatment was superior to wait-list on most outcome measures. Across the entire sample, reductions in social anxiety, global severity, general anxiety, and depression were observed at posttest and 3-month follow-up. These findings provide preliminary support for using this self-help workbook for individuals with mild to moderate social anxiety in conjunction with infrequent therapist visits to reinforce the treatment principles. Study limitations and future directions are discussed. PMID:18514614

  4. Striking a Balance in Communicating Pharmacogenetic Test Results: Promoting Comprehension and Minimizing Adverse Psychological and Behavioral Response

    PubMed Central

    Haga, Susanne B.; Mills, Rachel; Bosworth, Hayden

    2014-01-01

    Objective Pharmacogenetic (PGx) testing can provide information about a patient’s likelihood to respond to a medication or experience an adverse event, and be used to inform medication selection and/or dosing. Promoting patient comprehension of PGx test results will be important to improving engagement and understanding of treatment decisions Methods The discussion in this paper is based on our experiences and the literature on communication of genetic test results for disease risk and broad risk communication strategies. Results Clinical laboratory reports often describe PGx test results using standard terminology such as ‘poor metabolizer’ or ‘ultra-rapid metabolizer.’ While this type of terminology may promote patient recall with its simple, yet descriptive nature, it may be difficult for some patients to comprehend and/or cause adverse psychological or behavioral responses. Conclusion The language used to communicate results and their significance to patients will be important to consider in order to minimize confusion and potential psychological consequences such as increased anxiety that can adversely impact medication-taking behaviors. Practice Implications Due to patients’ unfamiliarity with PGx testing and the potential for confusion, adverse psychological effects, and decreased medication adherence, health providers need to be cognizant of the language used in discussing PGx test results with patients. PMID:24985359

  5. A fragile zero watermarking scheme to detect and characterize malicious modifications in database relations.

    PubMed

    Khan, Aihab; Husain, Syed Afaq

    2013-01-01

    We put forward a fragile zero watermarking scheme to detect and characterize malicious modifications made to a database relation. Most of the existing watermarking schemes for relational databases introduce intentional errors or permanent distortions as marks into the database original content. These distortions inevitably degrade the data quality and data usability as the integrity of a relational database is violated. Moreover, these fragile schemes can detect malicious data modifications but do not characterize the tempering attack, that is, the nature of tempering. The proposed fragile scheme is based on zero watermarking approach to detect malicious modifications made to a database relation. In zero watermarking, the watermark is generated (constructed) from the contents of the original data rather than introduction of permanent distortions as marks into the data. As a result, the proposed scheme is distortion-free; thus, it also resolves the inherent conflict between security and imperceptibility. The proposed scheme also characterizes the malicious data modifications to quantify the nature of tempering attacks. Experimental results show that even minor malicious modifications made to a database relation can be detected and characterized successfully. PMID:23818831

  6. A Fragile Zero Watermarking Scheme to Detect and Characterize Malicious Modifications in Database Relations

    PubMed Central

    Husain, Syed Afaq

    2013-01-01

    We put forward a fragile zero watermarking scheme to detect and characterize malicious modifications made to a database relation. Most of the existing watermarking schemes for relational databases introduce intentional errors or permanent distortions as marks into the database original content. These distortions inevitably degrade the data quality and data usability as the integrity of a relational database is violated. Moreover, these fragile schemes can detect malicious data modifications but do not characterize the tempering attack, that is, the nature of tempering. The proposed fragile scheme is based on zero watermarking approach to detect malicious modifications made to a database relation. In zero watermarking, the watermark is generated (constructed) from the contents of the original data rather than introduction of permanent distortions as marks into the data. As a result, the proposed scheme is distortion-free; thus, it also resolves the inherent conflict between security and imperceptibility. The proposed scheme also characterizes the malicious data modifications to quantify the nature of tempering attacks. Experimental results show that even minor malicious modifications made to a database relation can be detected and characterized successfully. PMID:23818831

  7. Socio-economic variation in price minimizing behaviors: findings from the International Tobacco Control (ITC) Four Country Survey.

    PubMed

    Licht, Andrea S; Hyland, Andrew J; O'Connor, Richard J; Chaloupka, Frank J; Borland, Ron; Fong, Geoffrey T; Nargis, Nigar; Cummings, K Michael

    2011-01-01

    This paper examines how socio-economic status (SES) modifies how smokers adjust to changes in the price of tobacco products through utilization of multiple price minimizing techniques. Data come from the International Tobacco Control Policy Evaluation (ITC) Four Country Survey, nationally representative samples of adult smokers and includes respondents from Canada, the United States, the United Kingdom and Australia. Cross-sectional analyses were completed among 8,243 respondents (7,038 current smokers) from the survey wave conducted between October 2006 and February 2007. Analyses examined predictors of purchasing from low/untaxed sources, using discount cigarettes or roll-your-own (RYO) tobacco, purchasing cigarettes in cartons, and engaging in high levels of price and tax avoidance at last purchase. All analyses tested for interactions with SES and were weighted to account for changing and under-represented demographics. Relatively high levels of price and tax avoidance behaviors were present; 8% reported buying from low or untaxed source; 36% used discount or generic brands, 13.5% used RYO tobacco, 29% reported purchasing cartons, and 63% reported using at least one of these high price avoidance behaviors. Respondents categorized as having low SES were approximately 26% less likely to report using low or untaxed sources and 43% less likely to purchase tobacco by the carton. However, respondents with low SES were 85% more likely to report using discount brands/RYO compared to participants with higher SES. Overall, lower SES smokers were 25% more likely to engage in at least one or more tax avoidance behaviors compared to their higher SES counterparts. Price and tax avoidance behaviors are relatively common among smokers of all SES strata, but strategies differed with higher SES groups more likely to report traveling to a low-tax location to avoid paying higher prices, purchase duty free tobacco, and purchase by cartons instead of packs all of which were less

  8. Effect of soaking in noni (Morinda citrifolia) juice on the microbiological and color behavior of Haden minimally processed mango.

    PubMed

    Ulloa, José Armando; González Tapia, Noemí T; Rosas Ulloa, Petra; Ramírez Ramírez, José Carmen; Ulloa Rangel, Blanca E

    2015-05-01

    The purpose of this study was to evaluate the effect of soaking in noni juice on the microbiological and color behavior of minimally processed mango. Two batches of Haden mango cubes were treated by immersion in noni juice for 2.5 or 5.0 min. Each batch was packed in polypropylene boxes and stored at 6 °C for up to 15 days; in addition, a control group of mango cubes was prepared by immersion in sterile water for the same duration. According to the results, the soaking of mango cubes in noni juice had an antimicrobial effect on mesophilic aerobic bacteria, molds and yeasts during storage at 6 °C for 15 days, without significantly (P < 0.05) affecting the CIE L*, a*, b*, chroma and hue angle values, in comparison with the control after 12 days of storage. The noni juice soaking treatment was demonstrated to be a potentially valuable technology for decontamination of fresh-cut fruit surfaces. PMID:25892812

  9. Impact of malicious servers over trust and reputation models in wireless sensor networks

    NASA Astrophysics Data System (ADS)

    Verma, Vinod Kumar; Singh, Surinder; Pathak, N. P.

    2016-03-01

    This article deals with the impact of malicious servers over different trust and reputation models in wireless sensor networks. First, we analysed the five trust and reputation models, namely BTRM-WSN, Eigen trust, peer trust, power trust, linguistic fuzzy trust model. Further, we proposed wireless sensor network design for optimisation of these models. Finally, influence of malicious servers on the behaviour of above mentioned trust and reputation models is discussed. Statistical analysis has been carried out to prove the validity of our proposal.

  10. Accuracy comparison among different machine learning techniques for detecting malicious codes

    NASA Astrophysics Data System (ADS)

    Narang, Komal

    2016-03-01

    In this paper, a machine learning based model for malware detection is proposed. It can detect newly released malware i.e. zero day attack by analyzing operation codes on Android operating system. The accuracy of Naïve Bayes, Support Vector Machine (SVM) and Neural Network for detecting malicious code has been compared for the proposed model. In the experiment 400 benign files, 100 system files and 500 malicious files have been used to construct the model. The model yields the best accuracy 88.9% when neural network is used as classifier and achieved 95% and 82.8% accuracy for sensitivity and specificity respectively.

  11. Assisting People with Multiple Disabilities and Minimal Motor Behavior to Improve Computer Drag-and-Drop Efficiency through a Mouse Wheel

    ERIC Educational Resources Information Center

    Shih, Ching-Hsiang

    2011-01-01

    This study evaluated whether two people with multiple disabilities and minimal motor behavior would be able to improve their Drag-and-Drop (DnD) performance using their finger/thumb poke ability with a mouse scroll wheel through a Dynamic Drag-and-Drop Assistive Program (DDnDAP). A multiple probe design across participants was used in this study…

  12. Teaching Generative Reading Via Recombination of Minimal Textual Units: A Legacy of Verbal Behavior to Children in Brazil

    PubMed Central

    de Souza, Deisy G.; de Rose, Julio C.; Faleiros, Thais C.; Bortoloti, Renato; Hanna, Elenice Seixas; McIlvane, William J.

    2009-01-01

    This paper reports results of two studies that sought to teach generative reading skills to a large group of Brazilian children who were exhibiting protracted failure in school. Inspired by Skinner’s analysis of verbal relations and minimal verbal units, the methodology took advantage of certain characteristics of Portuguese. Many words in this language are comprised of two-letter syllabic units (e.g., BO+LA= ball, CA+BO= handle, LA+TA= can) that can be recombined to form new words (e.g., BOCA= mouth, BOTA= boot), thus establishing a route to generative reading via recombinative generalization. Such syllabic units were incorporated within curricular framework that used matching-to-sample and learning by exclusion methods to teach matching relations involving pictures, printed and spoken words, and printed and spoken syllables. Study 1 was conducted within a university-based learning center that maintained certain aspects of laboratory conditions. It showed that teaching textual relations between dictated and printed syllables could control procedurally the inter- and intra-participant variability observed in past studies that lacked this feature -resulting in virtually universally positive teaching outcomes. Study 2 was conducted in a public school programs that applied the same basic training methodology. Positive training outcomes in an experimental group were approximately 3–5 times greater than that in a placebo control group. Together, these studies illustrate that the functional analysis in Verbal Behavior is having a direct impact in educational science in Brazil. It has led to procedures that can be effectively translated from the laboratory to the community via delivery systems that can be implemented in the developing world. PMID:19960112

  13. Leveling up and down: the experiences of benign and malicious envy.

    PubMed

    van de Ven, Niels; Zeelenberg, Marcel; Pieters, Rik

    2009-06-01

    Envy is the painful emotion caused by the good fortune of others. This research empirically supports the distinction between two qualitatively different types of envy, namely benign and malicious envy. It reveals that the experience of benign envy leads to a moving-up motivation aimed at improving one's own position, whereas the experience of malicious envy leads to a pulling-down motivation aimed at damaging the position of the superior other. Study 1 used guided recall of the two envy types in a culture (the Netherlands) that has separate words for benign and malicious envy. Analyses of the experiential content of these emotions found the predicted differences. Study 2 and 3 used one sample from the United States and one from Spain, respectively, where a single word exists for both envy types. A latent class analysis based on the experiential content of envy confirmed the existence of separate experiences of benign and malicious envy in both these cultures as well. The authors discuss the implications of distinguishing the two envy types for theories of cooperation, group performance, and Schadenfreude. PMID:19485619

  14. The effects of malicious nodes on performance of mobile ad hoc networks

    NASA Astrophysics Data System (ADS)

    Li, Fanzhi; Shi, Xiyu; Jassim, Sabah; Adams, Christopher

    2006-05-01

    Wireless ad hoc networking offers convenient infrastructureless communication over the shared wireless channel. However, the nature of ad hoc networks makes them vulnerable to security attacks. Unlike their wired counterpart, infrastructureless ad hoc networks do not have a clear line of defense, their topology is dynamically changing, and every mobile node can receive messages from its neighbors and can be contacted by all other nodes in its neighborhood. This poses a great danger to network security if some nodes behave in a malicious manner. The immediate concern about the security in this type of networks is how to protect the network and the individual mobile nodes against malicious act of rogue nodes from within the network. This paper is concerned with security aspects of wireless ad hoc networks. We shall present results of simulation experiments on ad hoc network's performance in the presence of malicious nodes. We shall investigate two types of attacks and the consequences will be simulated and quantified in terms of loss of packets and other factors. The results show that network performance, in terms of successful packet delivery ratios, significantly deteriorates when malicious nodes act according to the defined misbehaving characteristics.

  15. On the Performance of Online Learning Methods for Detecting Malicious Executables

    NASA Astrophysics Data System (ADS)

    Maloof, Marcus A.

    We present results from an empirical study of seven online-learning methods on the task of detecting previously unseen malicious executables. Malicious software has disrupted computer and network operation and has compromised or destroyed sensitive information. Methods of machine learning, which build predictive models that generalize training data, have proven useful for detecting previously unseen malware. In previous studies, batch methods detected malicious and benign executables with high true-positive and true-negative rates, but doing so required significant time and space, which may limit applicability. Online methods of learning can update models quickly with only a single example, but potential trade-offs in performance are not well-understood for this task. Accuracy of the best performing online methods was 93#x0025;, which was 3-4% lower than that of batch methods. For applications that require immediate updates of models, this may be an acceptable trade-off. Our study characterizes these tradeoffs, thereby giving researchers and practitioners insights into the performance of online methods of machine learning on the task of detecting malicious executables.

  16. Detecting Targeted Malicious Email through Supervised Classification of Persistent Threat and Recipient Oriented Features

    ERIC Educational Resources Information Center

    Amin, Rohan Mahesh

    2010-01-01

    Targeted email attacks to enable computer network exploitation have become more prevalent, more insidious, and more widely documented in recent years. Beyond nuisance spam or phishing designed to trick users into revealing personal information, targeted malicious email (TME) facilitates computer network exploitation and the gathering of sensitive…

  17. Non-developmental item computer systems and the malicious software threat

    NASA Technical Reports Server (NTRS)

    Bown, Rodney L.

    1991-01-01

    The following subject areas are covered: a DOD development system - the Army Secure Operating System; non-development commercial computer systems; security, integrity, and assurance of service (SI and A); post delivery SI and A and malicious software; computer system unique attributes; positive feedback to commercial computer systems vendors; and NDI (Non-Development Item) computers and software safety.

  18. Do you see what I see? Can non-experts with minimal training reproduce expert ratings in behavioral assessments of working dogs?

    PubMed

    Fratkin, Jamie L; Sinn, David L; Thomas, Scott; Hilliard, Stewart; Olson, Zezelia; Gosling, Samuel D

    2015-01-01

    Working-dog organizations often use behavioral ratings by experts to evaluate a dog's likelihood of success. However, these experts are frequently under severe time constraints. One way to alleviate the pressure on limited organizational resources would be to use non-experts to assess dog behavior. Here, in populations of military working dogs (Study 1) and explosive-detection dogs (Study 2), we evaluated the reliability and validity of behavioral ratings assessed by minimally trained non-experts from videotapes. Analyses yielded evidence for generally good levels of inter-observer reliability and criterion validity (indexed by convergence between the non-expert ratings and ratings made previously by experts). We found some variation across items in Study 2 such that reliability and validity was significantly lower for three out of the 18 items, and one item had reliability and validity estimates that were impacted heavily by the behavioral test environment. There were no differences in reliability and validity based on the age of the dog. Overall the results suggest that ratings made by minimally trained non-experts for most items can serve as a viable alternative to expert ratings freeing limited resources of highly trained staff. This article is part of a Special Issue entitled: Canine Behavior. PMID:25267466

  19. An Evaluation of Machine Learning Methods to Detect Malicious SCADA Communications

    SciTech Connect

    Beaver, Justin M; Borges, Raymond Charles; Buckner, Mark A

    2013-01-01

    Critical infrastructure Supervisory Control and Data Acquisition (SCADA) systems were designed to operate on closed, proprietary networks where a malicious insider posed the greatest threat potential. The centralization of control and the movement towards open systems and standards has improved the efficiency of industrial control, but has also exposed legacy SCADA systems to security threats that they were not designed to mitigate. This work explores the viability of machine learning methods in detecting the new threat scenarios of command and data injection. Similar to network intrusion detection systems in the cyber security domain, the command and control communications in a critical infrastructure setting are monitored, and vetted against examples of benign and malicious command traffic, in order to identify potential attack events. Multiple learning methods are evaluated using a dataset of Remote Terminal Unit communications, which included both normal operations and instances of command and data injection attack scenarios.

  20. Dynamics of a Delayed Model for the Transmission of Malicious Objects in Computer Network

    PubMed Central

    Yang, Huizhong

    2014-01-01

    An SEIQRS model for the transmission of malicious objects in computer network with two delays is investigated in this paper. We show that possible combination of the two delays can affect the stability of the model and make the model bifurcate periodic solutions under some certain conditions. For further investigation, properties of the periodic solutions are studied by using the normal form method and center manifold theory. Finally, some numerical simulations are given to justify the theoretical results. PMID:25147837

  1. Automatic Identification of Critical Data Items in a Database to Mitigate the Effects of Malicious Insiders

    NASA Astrophysics Data System (ADS)

    White, Jonathan; Panda, Brajendra

    A major concern for computer system security is the threat from malicious insiders who target and abuse critical data items in the system. In this paper, we propose a solution to enable automatic identification of critical data items in a database by way of data dependency relationships. This identification of critical data items is necessary because insider threats often target mission critical data in order to accomplish malicious tasks. Unfortunately, currently available systems fail to address this problem in a comprehensive manner. It is more difficult for non-experts to identify these critical data items because of their lack of familiarity and due to the fact that data systems are constantly changing. By identifying the critical data items automatically, security engineers will be better prepared to protect what is critical to the mission of the organization and also have the ability to focus their security efforts on these critical data items. We have developed an algorithm that scans the database logs and forms a directed graph showing which items influence a large number of other items and at what frequency this influence occurs. This graph is traversed to reveal the data items which have a large influence throughout the database system by using a novel metric based formula. These items are critical to the system because if they are maliciously altered or stolen, the malicious alterations will spread throughout the system, delaying recovery and causing a much more malignant effect. As these items have significant influence, they are deemed to be critical and worthy of extra security measures. Our proposal is not intended to replace existing intrusion detection systems, but rather is intended to complement current and future technologies. Our proposal has never been performed before, and our experimental results have shown that it is very effective in revealing critical data items automatically.

  2. Dynamics of a delayed model for the transmission of malicious objects in computer network.

    PubMed

    Zhang, Zizhen; Yang, Huizhong

    2014-01-01

    An SEIQRS model for the transmission of malicious objects in computer network with two delays is investigated in this paper. We show that possible combination of the two delays can affect the stability of the model and make the model bifurcate periodic solutions under some certain conditions. For further investigation, properties of the periodic solutions are studied by using the normal form method and center manifold theory. Finally, some numerical simulations are given to justify the theoretical results. PMID:25147837

  3. Minimizing the cost of translocation failure with decision-tree models that predict species' behavioral response in translocation sites.

    PubMed

    Ebrahimi, Mehregan; Ebrahimie, Esmaeil; Bull, C Michael

    2015-08-01

    The high number of failures is one reason why translocation is often not recommended. Considering how behavior changes during translocations may improve translocation success. To derive decision-tree models for species' translocation, we used data on the short-term responses of an endangered Australian skink in 5 simulated translocations with different release conditions. We used 4 different decision-tree algorithms (decision tree, decision-tree parallel, decision stump, and random forest) with 4 different criteria (gain ratio, information gain, gini index, and accuracy) to investigate how environmental and behavioral parameters may affect the success of a translocation. We assumed behavioral changes that increased dispersal away from a release site would reduce translocation success. The trees became more complex when we included all behavioral parameters as attributes, but these trees yielded more detailed information about why and how dispersal occurred. According to these complex trees, there were positive associations between some behavioral parameters, such as fight and dispersal, that showed there was a higher chance, for example, of dispersal among lizards that fought than among those that did not fight. Decision trees based on parameters related to release conditions were easier to understand and could be used by managers to make translocation decisions under different circumstances. PMID:25737134

  4. Behavioral investigation of the influence of social categorization on empathy for pain: a minimal group paradigm study.

    PubMed

    Montalan, Benoît; Lelard, Thierry; Godefroy, Olivier; Mouras, Harold

    2012-01-01

    Research on empathy for pain has provided evidence of an empathic bias toward racial ingroup members. In this study, we used for the first time the "minimal group paradigm" in which participants were assigned to artificial groups and required to perform pain judgments of pictures of hands and feet in painful or non-painful situations from self, ingroup, and outgroup perspectives. Findings showed that the mere categorization of people into two distinct arbitrary social groups appears to be sufficient to elicit an ingroup bias in empathy for pain. PMID:23087657

  5. Behavioral Investigation of the Influence of Social Categorization on Empathy for Pain: A Minimal Group Paradigm Study

    PubMed Central

    Montalan, Benoît; Lelard, Thierry; Godefroy, Olivier; Mouras, Harold

    2012-01-01

    Research on empathy for pain has provided evidence of an empathic bias toward racial ingroup members. In this study, we used for the first time the “minimal group paradigm” in which participants were assigned to artificial groups and required to perform pain judgments of pictures of hands and feet in painful or non-painful situations from self, ingroup, and outgroup perspectives. Findings showed that the mere categorization of people into two distinct arbitrary social groups appears to be sufficient to elicit an ingroup bias in empathy for pain. PMID:23087657

  6. Minimal cosmography

    NASA Astrophysics Data System (ADS)

    Piazza, Federico; Schücker, Thomas

    2016-04-01

    The minimal requirement for cosmography—a non-dynamical description of the universe—is a prescription for calculating null geodesics, and time-like geodesics as a function of their proper time. In this paper, we consider the most general linear connection compatible with homogeneity and isotropy, but not necessarily with a metric. A light-cone structure is assigned by choosing a set of geodesics representing light rays. This defines a "scale factor" and a local notion of distance, as that travelled by light in a given proper time interval. We find that the velocities and relativistic energies of free-falling bodies decrease in time as a consequence of cosmic expansion, but at a rate that can be different than that dictated by the usual metric framework. By extrapolating this behavior to photons' redshift, we find that the latter is in principle independent of the "scale factor". Interestingly, redshift-distance relations and other standard geometric observables are modified in this extended framework, in a way that could be experimentally tested. An extremely tight constraint on the model, however, is represented by the blackbody-ness of the cosmic microwave background. Finally, as a check, we also consider the effects of a non-metric connection in a different set-up, namely, that of a static, spherically symmetric spacetime.

  7. Searching for a minimal set of behaviors for autism detection through feature selection-based machine learning.

    PubMed

    Kosmicki, J A; Sochat, V; Duda, M; Wall, D P

    2015-01-01

    Although the prevalence of autism spectrum disorder (ASD) has risen sharply in the last few years reaching 1 in 68, the average age of diagnosis in the United States remains close to 4--well past the developmental window when early intervention has the largest gains. This emphasizes the importance of developing accurate methods to detect risk faster than the current standards of care. In the present study, we used machine learning to evaluate one of the best and most widely used instruments for clinical assessment of ASD, the Autism Diagnostic Observation Schedule (ADOS) to test whether only a subset of behaviors can differentiate between children on and off the autism spectrum. ADOS relies on behavioral observation in a clinical setting and consists of four modules, with module 2 reserved for individuals with some vocabulary and module 3 for higher levels of cognitive functioning. We ran eight machine learning algorithms using stepwise backward feature selection on score sheets from modules 2 and 3 from 4540 individuals. We found that 9 of the 28 behaviors captured by items from module 2, and 12 of the 28 behaviors captured by module 3 are sufficient to detect ASD risk with 98.27% and 97.66% accuracy, respectively. A greater than 55% reduction in the number of behaviorals with negligible loss of accuracy across both modules suggests a role for computational and statistical methods to streamline ASD risk detection and screening. These results may help enable development of mobile and parent-directed methods for preliminary risk evaluation and/or clinical triage that reach a larger percentage of the population and help to lower the average age of detection and diagnosis. PMID:25710120

  8. Searching for a minimal set of behaviors for autism detection through feature selection-based machine learning

    PubMed Central

    Kosmicki, J A; Sochat, V; Duda, M; Wall, D P

    2015-01-01

    Although the prevalence of autism spectrum disorder (ASD) has risen sharply in the last few years reaching 1 in 68, the average age of diagnosis in the United States remains close to 4—well past the developmental window when early intervention has the largest gains. This emphasizes the importance of developing accurate methods to detect risk faster than the current standards of care. In the present study, we used machine learning to evaluate one of the best and most widely used instruments for clinical assessment of ASD, the Autism Diagnostic Observation Schedule (ADOS) to test whether only a subset of behaviors can differentiate between children on and off the autism spectrum. ADOS relies on behavioral observation in a clinical setting and consists of four modules, with module 2 reserved for individuals with some vocabulary and module 3 for higher levels of cognitive functioning. We ran eight machine learning algorithms using stepwise backward feature selection on score sheets from modules 2 and 3 from 4540 individuals. We found that 9 of the 28 behaviors captured by items from module 2, and 12 of the 28 behaviors captured by module 3 are sufficient to detect ASD risk with 98.27% and 97.66% accuracy, respectively. A greater than 55% reduction in the number of behaviorals with negligible loss of accuracy across both modules suggests a role for computational and statistical methods to streamline ASD risk detection and screening. These results may help enable development of mobile and parent-directed methods for preliminary risk evaluation and/or clinical triage that reach a larger percentage of the population and help to lower the average age of detection and diagnosis. PMID:25710120

  9. Detecting Heap-Spraying Code Injection Attacks in Malicious Web Pages Using Runtime Execution

    NASA Astrophysics Data System (ADS)

    Choi, Younghan; Kim, Hyoungchun; Lee, Donghoon

    The growing use of web services is increasing web browser attacks exponentially. Most attacks use a technique called heap spraying because of its high success rate. Heap spraying executes a malicious code without indicating the exact address of the code by copying it into many heap objects. For this reason, the attack has a high potential to succeed if only the vulnerability is exploited. Thus, attackers have recently begun using this technique because it is easy to use JavaScript to allocate the heap memory area. This paper proposes a novel technique that detects heap spraying attacks by executing a heap object in a real environment, irrespective of the version and patch status of the web browser. This runtime execution is used to detect various forms of heap spraying attacks, such as encoding and polymorphism. Heap objects are executed after being filtered on the basis of patterns of heap spraying attacks in order to reduce the overhead of the runtime execution. Patterns of heap spraying attacks are based on analysis of how an web browser accesses benign web sites. The heap objects are executed forcibly by changing the instruction register into the address of them after being loaded into memory. Thus, we can execute the malicious code without having to consider the version and patch status of the browser. An object is considered to contain a malicious code if the execution reaches a call instruction and then the instruction accesses the API of system libraries, such as kernel32.dll and ws_32.dll. To change registers and monitor execution flow, we used a debugger engine. A prototype, named HERAD(HEap spRAying Detector), is implemented and evaluated. In experiments, HERAD detects various forms of exploit code that an emulation cannot detect, and some heap spraying attacks that NOZZLE cannot detect. Although it has an execution overhead, HERAD produces a low number of false alarms. The processing time of several minutes is negligible because our research focuses on

  10. 76 FR 22925 - Assumption Buster Workshop: Abnormal Behavior Detection Finds Malicious Actors

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-25

    ... more than 50 miles from Washington DC. SUMMARY: The NCO, on behalf of the Special Cyber Operations Research and Engineering (SCORE) Committee, an interagency working group that coordinates cyber security... Coordination Office (NCO) for the Networking and Information Technology Research and Development...

  11. Trouble Brewing: Using Observations of Invariant Behavior to Detect Malicious Agency in Distributed Control Systems

    NASA Astrophysics Data System (ADS)

    McEvoy, Thomas Richard; Wolthusen, Stephen D.

    Recent research on intrusion detection in supervisory data acquisition and control (SCADA) and DCS systems has focused on anomaly detection at protocol level based on the well-defined nature of traffic on such networks. Here, we consider attacks which compromise sensors or actuators (including physical manipulation), where intrusion may not be readily apparent as data and computational states can be controlled to give an appearance of normality, and sensor and control systems have limited accuracy. To counter these, we propose to consider indirect relations between sensor readings to detect such attacks through concurrent observations as determined by control laws and constraints.

  12. An Efficient Energy based Detection of Malicious Node in Mobile Wireless Sensor Networks

    NASA Astrophysics Data System (ADS)

    Sharmila, S.; Umamaheswari, G.

    2012-03-01

    Mobile wireless sensor networks (MWSN) are composed of a large number of wireless sensors and they require a careful consumption of available energy to prolong the life of the network. From the security point of view, existing detection schemes consumes node energy and thus reduces the life time of the network. This paper focuses on energy based scheme for detecting the malicious node in the forward routing path. This detection scheme suits any standard routing protocol. The forward route selection path is identified by using dynamic source routing protocol. The proposed scheme is simulated in glomosim and evaluated using packet throughput, percentage of byte overheads, energy consumption, and the accuracy of detection. The network with moderate mobility is used and the proposed scheme consumes 20 % of node energy.

  13. Prevention of Malicious Nodes Communication in MANETs by Using Authorized Tokens

    NASA Astrophysics Data System (ADS)

    Chandrakant, N.; Shenoy, P. Deepa; Venugopal, K. R.; Patnaik, L. M.

    A rapid increase of wireless networks and mobile computing applications has changed the landscape of network security. A MANET is more susceptible to the attacks than wired network. As a result, attacks with malicious intent have been and will be devised to take advantage of these vulnerabilities and to cripple the MANET operation. Hence we need to search for new architecture and mechanisms to protect the wireless networks and mobile computing applications. In this paper, we examine the nodes that come under the vicinity of base node and members of the network and communication is provided to genuine nodes only. It is found that the proposed algorithm is a effective algorithm for security in MANETs.

  14. Minimal Reduplication

    ERIC Educational Resources Information Center

    Kirchner, Jesse Saba

    2010-01-01

    This dissertation introduces Minimal Reduplication, a new theory and framework within generative grammar for analyzing reduplication in human language. I argue that reduplication is an emergent property in multiple components of the grammar. In particular, reduplication occurs independently in the phonology and syntax components, and in both cases…

  15. Taxonomic minimalism.

    PubMed

    Beattle, A J; Oliver, I

    1994-12-01

    Biological surveys are in increasing demand while taxonomic resources continue to decline. How much formal taxonomy is required to get the job done? The answer depends on the kind of job but it is possible that taxonomic minimalism, especially (1) the use of higher taxonomic ranks, (2) the use of morphospecies rather than species (as identified by Latin binomials), and (3) the involvement of taxonomic specialists only for training and verification, may offer advantages for biodiversity assessment, environmental monitoring and ecological research. As such, formal taxonomy remains central to the process of biological inventory and survey but resources may be allocated more efficiently. For example, if formal Identification is not required, resources may be concentrated on replication and increasing sample sizes. Taxonomic minimalism may also facilitate the inclusion in these activities of important but neglected groups, especially among the invertebrates, and perhaps even microorganisms. PMID:21236933

  16. Tumor necrosis factor-α synthesis inhibitor, 3’6,dithiothalidomide, reverses behavioral impairments induced by minimal traumatic brain injury in mice

    PubMed Central

    Baratz, Renana; Tweedie, David; Rubovitch, Vardit; Luo, Weiming; Yoon, Jeong Seon; Hoffer, Barry J.; Greig, Nigel H.; Pick, Chaim G.

    2012-01-01

    Mild traumatic brain injury (mTBI) patients do not show clear structural brain defects and, in general, do not require hospitalization, but frequently suffer from long-lasting cognitive, behavioral and emotional difficulties. Although there is no current effective treatment or cure for mTBI, tumor necrosis factor-alpha (TNF-α), a cytokine fundamental in the systemic inflammatory process, represents a potential drug target. TNF-α levels increase after mTBI and may induce or exacerbate secondary damage to brain tissue. The present study evaluated the efficacy of the experimental TNF-α synthesis inhibitor, 3,6'-dithiothalidomide, on recovery of mice from mTBI in a closed head weight-drop model that induces an acute elevation in brain TNF-α and an impairment in cognitive performance, as assessed by the Y-maze, by novel object recognition and by passive avoidance paradigms at 72 hr and 7 days after injury. These impairments were fully ameliorated in mice that received a one time administration of 3,6'-dithiothalidomide at either a low (28 mg/kg) or high (56 mg/kg) dose provided either 1 hr prior to injury, or at 1 or 12 hr post injury. Together, these results implicate TNF-α as a drug target for mTBI and suggests that 3,6'-dithiothalidomide may act as a neuroprotective drug to minimize impairment. PMID:21740439

  17. Develop a solution for protecting and securing enterprise networks from malicious attacks

    NASA Astrophysics Data System (ADS)

    Kamuru, Harshitha; Nijim, Mais

    2014-05-01

    In the world of computer and network security, there are myriad ways to launch an attack, which, from the perspective of a network, can usually be defined as "traffic that has huge malicious intent." Firewall acts as one of the measure in order to secure the device from incoming unauthorized data. There are infinite number of computer attacks that no firewall can prevent, such as those executed locally on the machine by a malicious user. From the network's perspective, there are numerous types of attack. All the attacks that degrade the effectiveness of data can be grouped into two types: brute force and precision. The Firewall that belongs to Juniper has the capability to protect against both types of attack. Denial of Service (DoS) attacks are one of the most well-known network security threats under brute force attacks, which is largely due to the high-profile way in which they can affect networks. Over the years, some of the largest, most respected Internet sites have been effectively taken offline by Denial of Service (DOS) attacks. A DoS attack typically has a singular focus, namely, to cause the services running on a particular host or network to become unavailable. Some DoS attacks exploit vulnerabilities in an operating system and cause it to crash, such as the infamous Win nuke attack. Others submerge a network or device with traffic so that there are no more resources to handle legitimate traffic. Precision attacks typically involve multiple phases and often involves a bit more thought than brute force attacks, all the way from reconnaissance to machine ownership. Before a precision attack is launched, information about the victim needs to be gathered. This information gathering typically takes the form of various types of scans to determine available hosts, networks, and ports. The hosts available on a network can be determined by ping sweeps. The available ports on a machine can be located by port scans. Screens cover a wide variety of attack traffic

  18. A malicious pattern detection engine for embedded security systems in the Internet of Things.

    PubMed

    Oh, Doohwan; Kim, Deokho; Ro, Won Woo

    2014-01-01

    With the emergence of the Internet of Things (IoT), a large number of physical objects in daily life have been aggressively connected to the Internet. As the number of objects connected to networks increases, the security systems face a critical challenge due to the global connectivity and accessibility of the IoT. However, it is difficult to adapt traditional security systems to the objects in the IoT, because of their limited computing power and memory size. In light of this, we present a lightweight security system that uses a novel malicious pattern-matching engine. We limit the memory usage of the proposed system in order to make it work on resource-constrained devices. To mitigate performance degradation due to limitations of computation power and memory, we propose two novel techniques, auxiliary shifting and early decision. Through both techniques, we can efficiently reduce the number of matching operations on resource-constrained systems. Experiments and performance analyses show that our proposed system achieves a maximum speedup of 2.14 with an IoT object and provides scalable performance for a large number of patterns. PMID:25521382

  19. A theoretical estimation for the optimal network robustness measure R against malicious node attacks

    NASA Astrophysics Data System (ADS)

    Ma, Liangliang; Liu, Jing; Duan, Boping; Zhou, Mingxing

    2015-07-01

    In a recent work (Schneider C. M. et al., Proc. Natl. Acad. Sci. U.S.A., 108 (2011) 3838), Schneider et al. introduced an effective measure R to evaluate the network robustness against malicious attacks on nodes. Take R as the objective function, they used a heuristic algorithm to optimize the network robustness. In this paper, a theoretical analysis is conducted to estimate the value of R for different types of networks, including regular networks, WS networks, ER networks, and BA networks. The experimental results show that the theoretical value of R is approximately equal to that of optimized networks. Furthermore, the theoretical analysis also shows that regular networks are the most robust than other networks. To validate this result, a heuristic method is proposed to optimize the network structure, in which the degree distribution can be changed and the number of nodes and edges remains invariant. The optimization results show that the degree of most nodes in the optimal networks is close to the average degree, and the optimal network topology is close to regular networks, which confirms the theoretical analysis.

  20. A memetic algorithm for enhancing the robustness of scale-free networks against malicious attacks

    NASA Astrophysics Data System (ADS)

    Zhou, Mingxing; Liu, Jing

    2014-09-01

    The robustness of the infrastructure of various real-life systems, which can be represented by networks and manifests the scale-free property, is of great importance. Thus, in this paper, a new memetic algorithm (MA), which is a type of effective optimization method combining both global and local searches, is proposed to enhance the robustness of scale-free (RSF) networks against malicious attacks (MA) without changing the degree distribution. The proposed algorithm is abbreviated as MA-RSF MA. Especially, with the intrinsic properties of the problem of optimizing network structure in mind, a crossover operator which can perform global search and a local search operator are designed. In the experiments, both synthetic scale-free networks and real-world networks, like the EU power grid network and the real Internet at the level of autonomous system (AS), are used. MA-RSFMA shows a strong ability in searching for the most robust network structure, and clearly outperforms existing local search methods.

  1. A Malicious Pattern Detection Engine for Embedded Security Systems in the Internet of Things

    PubMed Central

    Oh, Doohwan; Kim, Deokho; Ro, Won Woo

    2014-01-01

    With the emergence of the Internet of Things (IoT), a large number of physical objects in daily life have been aggressively connected to the Internet. As the number of objects connected to networks increases, the security systems face a critical challenge due to the global connectivity and accessibility of the IoT. However, it is difficult to adapt traditional security systems to the objects in the IoT, because of their limited computing power and memory size. In light of this, we present a lightweight security system that uses a novel malicious pattern-matching engine. We limit the memory usage of the proposed system in order to make it work on resource-constrained devices. To mitigate performance degradation due to limitations of computation power and memory, we propose two novel techniques, auxiliary shifting and early decision. Through both techniques, we can efficiently reduce the number of matching operations on resource-constrained systems. Experiments and performance analyses show that our proposed system achieves a maximum speedup of 2.14 with an IoT object and provides scalable performance for a large number of patterns. PMID:25521382

  2. Design of Cyber Attack Precursor Symptom Detection Algorithm through System Base Behavior Analysis and Memory Monitoring

    NASA Astrophysics Data System (ADS)

    Jung, Sungmo; Kim, Jong Hyun; Cagalaban, Giovanni; Lim, Ji-Hoon; Kim, Seoksoo

    More recently, botnet-based cyber attacks, including a spam mail or a DDos attack, have sharply increased, which poses a fatal threat to Internet services. At present, antivirus businesses make it top priority to detect malicious code in the shortest time possible (Lv.2), based on the graph showing a relation between spread of malicious code and time, which allows them to detect after malicious code occurs. Despite early detection, however, it is not possible to prevent malicious code from occurring. Thus, we have developed an algorithm that can detect precursor symptoms at Lv.1 to prevent a cyber attack using an evasion method of 'an executing environment aware attack' by analyzing system behaviors and monitoring memory.

  3. Intense or malicious? The decoding of eyebrow-lowering frowning in laughter animations depends on the presentation mode.

    PubMed

    Hofmann, Jennifer

    2014-01-01

    Joyful laughter is the only laughter type that has received sufficient validation in terms of morphology (i.e., face, voice). Still, it is unclear whether joyful laughter involves one prototypical facial-morphological configuration (Duchenne Display and mouth opening) to be decoded as such, or whether qualitatively distinct facial markers occur at different stages of laughter intensity. It was proposed that intense laughter goes along with eyebrow-lowering frowning, but in decoding studies of pictures, these "frowns" were associated with perceived maliciousness rather than higher intensity. Thus, two studies were conducted to investigate the influence of the presentation mode (static, dynamic) and eyebrow-lowering frowning on the perception of laughter animations of different intensity. In Study 1, participants (N = 110) were randomly assigned to two presentation modes (static pictures vs. dynamic videos) to watch animations of Duchenne laughter and laughter with added eyebrow-lowering frowning. Ratings on the intensity, valence, and contagiousness of the laughter were completed. In Study 2, participants (N = 55) saw both animation types in both presentation modes sequentially. Results confirmed that the static presentation lead to eyebrow-lowering frowning in intense laughter being perceived as more malicious, less intense, less benevolent, and less contagious compared to the dynamic presentation. This was replicated for maliciousness in Study 2, although participants could potentially infer the "frown" as a natural element of the laugh, as they had seen the video and the picture. Thus, a dynamic presentation is necessary for detecting graduating intensity markers in the joyfully laughing face. While this study focused on the decoding, future studies should investigate the encoding of frowning in laughter. This is important, as tools assessing facially expressed joy might need to account for laughter intensity markers that differ from the Duchenne Display. PMID

  4. Intense or malicious? The decoding of eyebrow-lowering frowning in laughter animations depends on the presentation mode

    PubMed Central

    Hofmann, Jennifer

    2014-01-01

    Joyful laughter is the only laughter type that has received sufficient validation in terms of morphology (i.e., face, voice). Still, it is unclear whether joyful laughter involves one prototypical facial-morphological configuration (Duchenne Display and mouth opening) to be decoded as such, or whether qualitatively distinct facial markers occur at different stages of laughter intensity. It was proposed that intense laughter goes along with eyebrow-lowering frowning, but in decoding studies of pictures, these “frowns” were associated with perceived maliciousness rather than higher intensity. Thus, two studies were conducted to investigate the influence of the presentation mode (static, dynamic) and eyebrow-lowering frowning on the perception of laughter animations of different intensity. In Study 1, participants (N = 110) were randomly assigned to two presentation modes (static pictures vs. dynamic videos) to watch animations of Duchenne laughter and laughter with added eyebrow-lowering frowning. Ratings on the intensity, valence, and contagiousness of the laughter were completed. In Study 2, participants (N = 55) saw both animation types in both presentation modes sequentially. Results confirmed that the static presentation lead to eyebrow-lowering frowning in intense laughter being perceived as more malicious, less intense, less benevolent, and less contagious compared to the dynamic presentation. This was replicated for maliciousness in Study 2, although participants could potentially infer the “frown” as a natural element of the laugh, as they had seen the video and the picture. Thus, a dynamic presentation is necessary for detecting graduating intensity markers in the joyfully laughing face. While this study focused on the decoding, future studies should investigate the encoding of frowning in laughter. This is important, as tools assessing facially expressed joy might need to account for laughter intensity markers that differ from the Duchenne Display

  5. FORENSIC ANALYSIS OF WINDOW’S® VIRTUAL MEMORY INCORPORATING THE SYSTEM’S PAGEFILE COUNTERINTELLIGENCE THROUGH MALICIOUS CODE ANALYSIS

    SciTech Connect

    Jared Stimson Edward Murphy

    2007-06-01

    FORENSIC ANALYSIS OF WINDOW’S® VIRTUAL MEMORY INCORPORATING THE SYSTEM’S PAGEFILE Computer Forensics is concerned with the use of computer investigation and analysis techniques in order to collect evidence suitable for presentation in court. The examination of volatile memory is a relatively new but important area in computer forensics. More recently criminals are becoming more forensically aware and are now able to compromise computers without accessing the hard disk of the target computer. This means that traditional incident response practice of pulling the plug will destroy the only evidence of the crime. While some techniques are available for acquiring the contents of main memory, few exist which can analyze these data in a meaningful way. One reason for this is how memory is managed by the operating system. Data belonging to one process can be distributed arbitrarily across physical memory or the hard disk, making it very difficult to recover useful information. This report will focus on how these disparate sources of information can be combined to give a single, contiguous address space for each process. Using address translation a tool is developed to reconstruct the virtual address space of a process by combining a physical memory dump with the page-file on the hard disk. COUNTERINTELLIGENCE THROUGH MALICIOUS CODE ANALYSIS As computer network technology continues to grow so does the reliance on this technology for everyday business functionality. To appeal to customers and employees alike, businesses are seeking an increased online prescience, and to increase productivity the same businesses are computerizing their day-to-day operations. The combination of a publicly accessible interface to the businesses network, and the increase in the amount of intellectual property present on these networks presents serious risks. All of this intellectual property now faces constant attacks from a wide variety of malicious software that is intended to uncover

  6. Hydrodynamic behavior and electrochemical impedance of the Hanging Meniscus Rotating Disk (HMRD) electrode. I - Meniscus shape under rotation. II - I-BIEM calculations of frequency dispersion and minimization

    NASA Technical Reports Server (NTRS)

    Cahan, Boris D.

    1991-01-01

    The shape equations for an HMRD in static and rotating configurations are developed and solved numerically. A rationale for the applicability of the standard Levich equations to the rotating case is given. The region of stability of the HMRD is examined, and the observed small negative intercept for a Levich plot is explained. The iterative boundary integral equation method is applied to the problem of frequency dispersion at an HMRD electrode. It is shown that a range of disk sizes and heights can be chosen to give almost uniform primary and secondary current distribution and minimal frequency disperison.

  7. Introducing Female Black Swiss Mice: Minimal Effects of Sex in a Strain-Specific Battery of Tests for Mania-Like Behavior and Response to Lithium.

    PubMed

    Ene, Hila M; Kara, Nirit Z; Einat, Haim

    2015-01-01

    Black Swiss (BS) mice were shown to be an advantageous strain to model behavioral domains of mania, but to date only male mice were tested, whereas bipolar disorder (BPD) is equally prevalent in women and men. This study was therefore designed to examine the possibility of using both male and female BS mice in future studies. Groups of male and female BS mice were compared with each other, with or without lithium treatment, in tests for domains of mania-like behavior including activity in an open field, sweet solution preference, elevated plus maze, forced swim and amphetamine-induced hyperactivity. The results indicate mostly a similarity between female and male BS mice, both naïve and after chronic lithium treatment. The results are discussed in the context of the deficiency in utilizing female mice in animal models research and suggest that both male and female BS mice can be used to model domains of mania-like behavior. PMID:25924800

  8. Esophagectomy - minimally invasive

    MedlinePlus

    Minimally invasive esophagectomy; Robotic esophagectomy; Removal of the esophagus - minimally invasive; Achalasia - esophagectomy; Barrett esophagus - esophagectomy; Esophageal cancer - esophagectomy - laparoscopic; Cancer of the ...

  9. Malicious whites, greedy women, and virtuous volunteers: negotiating social relations through clinical trial narratives in South Africa.

    PubMed

    Saethre, Eirik; Stadler, Jonathan

    2013-03-01

    As clinical trial research increasingly permeates sub-Saharan Africa, tales of purposeful HIV infection, blood theft, and other harmful outcomes are widely reported by participants and community members. Examining responses to the Microbicide Development Programme 301-a randomized, double-blind, placebo-controlled microbicide trial-we investigate the ways in which these accounts embed medical research within postcolonial contexts. We explore three popular narratives circulating around the Johannesburg trial site: malicious whites killing participants and selling their blood, greedy women enrolling in the trial solely for financial gain, and virtuous volunteers attempting to ensure their health and aid others through trial participation. We argue that trial participants and community members transform medical research into a meaningful tool that alternately affirms, debates, and challenges contemporary social relations. PMID:23674325

  10. SIV/Macaque Model of HIV Infection in Cocaine Users: Minimal Effects of Cocaine on Behavior, Virus Replication, and CNS Inflammation

    PubMed Central

    Weed, Michael; Adams, Robert J.; Hienz, Robert D.; Meulendyke, Kelly A.; Linde, Michael E.; Clements, Janice E.; Mankowski, Joseph L.; Zink, M. Christine

    2011-01-01

    Studies of the effects of drugs of abuse on HIV immune status, disease progression, and neuroAIDS have produced conflicting data and have not definitively shown whether this combination promotes cognitive impairment or disease progression. Using a consistent SIV–macaque model, we investigated the effects of cocaine on behavior, virologic parameters, and CNS inflammation. Macaques received either vehicle or chronic administration of behaviorally active doses of cocaine (1.7 or 3.2 mg/kg/day). Chronic cocaine administration reduced CD8+ T cell counts during acute and late stage infection but had no effect on CD4+ T cell counts. Low-dose cocaine-treated animals had lower CSF vRNA levels late in infection, but cocaine did not alter plasma viral load or vRNA or protein in brain. There were no differences in CSF CCL-2 or interleukin (IL)-6 levels or severity of encephalitis in cocaine-treated as compared to vehicle-treated macaques. There were no differences in brain inflammation or neurodegeneration markers, as determined by interferon (IFN)-β, MxA, CCL2, IL-6, TNFα, IFNγ, and indolamine 2,3-deoxygenase mRNA levels. APP levels also were not altered. The executive function of inhibitory control was not impaired in cocaine-treated or control animals following SIV infection. However, animals receiving 3.2 mg/kg/day cocaine performed more slowly in a bimanual motor test. Thus, chronic administration of cocaine produced only minor changes in behavior, encephalitis severity, CNS inflammation/neurodegeneration, and virus replication in SIV-infected pigtailed macaques, suggesting that cocaine would have only modest effects on the progression of neuroAIDS in HIV-infected individuals. PMID:21626125

  11. Depressive-like behavior observed with a minimal loss of locus coeruleus (LC) neurons following administration of 6-hydroxydopamine is associated with electrophysiological changes and reversed with precursors of norepinephrine.

    PubMed

    Szot, Patricia; Franklin, Allyn; Miguelez, Cristina; Wang, Yangqing; Vidaurrazaga, Igor; Ugedo, Luisa; Sikkema, Carl; Wilkinson, Charles W; Raskind, Murray A

    2016-02-01

    Depression is a common co-morbid condition most often observed in subjects with mild cognitive impairment (MCI) and during the early stages of Alzheimer's disease (AD). Dysfunction of the central noradrenergic nervous system is an important component in depression. In AD, locus coeruleus (LC) noradrenergic neurons are significantly reduced pathologically and the reduction of LC neurons is hypothesized to begin very early in the progression of the disorder; however, it is not known if dysfunction of the noradrenergic system due to early LC neuronal loss is involved in mediating depression in early AD. Therefore, the purpose of this study was to determine in an animal model if a loss of noradrenergic LC neurons results in depressive-like behavior. The LC noradrenergic neuronal population was reduced by the bilateral administration of the neurotoxin 6-hydroxydopamine (6-OHDA) directly into the LC. Forced swim test (FST) was performed three weeks after the administration of 6-OHDA (5, 10 and 14 μg/μl), animals administered the 5 μg/μl of 6-OHDA demonstrated a significant increase in immobility, indicating depressive-like behavior. This increase in immobility at the 5 μg/μl dose was observed with a minimal loss of LC noradrenergic neurons as compared to LC neuronal loss observed at 10 and 14 μg/μl dose. A significant positive correlation between the number of surviving LC neurons after 6-OHDA and FST immobile time was observed, suggesting that in animals with a minimal loss of LC neurons (or a greater number of surviving LC neurons) following 6-OHDA demonstrated depressive-like behavior. As the 6-OHDA-induced loss of LC neurons is increased, the time spent immobile is reduced. Depressive-like behavior was also observed with the 5 μg/μl dose of 6-OHDA with a second behavior test, sucrose consumption. FST increased immobility following 6-OHDA (5 μg/μl) was reversed by the administration of a single dose of L-1-3-4-dihydroxyphenylalanine (DOPA) or l-threo-3

  12. Behaviorism

    ERIC Educational Resources Information Center

    Moore, J.

    2011-01-01

    Early forms of psychology assumed that mental life was the appropriate subject matter for psychology, and introspection was an appropriate method to engage that subject matter. In 1913, John B. Watson proposed an alternative: classical S-R behaviorism. According to Watson, behavior was a subject matter in its own right, to be studied by the…

  13. Is goal ascription possible in minimal mindreading?

    PubMed

    Butterfill, Stephen A; Apperly, Ian A

    2016-03-01

    In this response to the commentary by Michael and Christensen, we first explain how minimal mindreading is compatible with the development of increasingly sophisticated mindreading behaviors that involve both executive functions and general knowledge and then sketch 1 approach to a minimal account of goal ascription. PMID:26901746

  14. Minimal change disease

    MedlinePlus

    ... seen under a very powerful microscope called an electron microscope. Minimal change disease is the most common ... biopsy and examination of the tissue with an electron microscope can show signs of minimal change disease.

  15. Minimal change disease

    MedlinePlus

    Minimal change nephrotic syndrome; Nil disease; Lipoid nephrosis; Idiopathic nephrotic syndrome of childhood ... which filter blood and produce urine. In minimal change disease, there is damage to the glomeruli. These ...

  16. Toward a Minimal Artificial Axon.

    PubMed

    Ariyaratne, Amila; Zocchi, Giovanni

    2016-07-01

    The electrophysiology of action potentials is usually studied in neurons, through relatively demanding experiments which are difficult to scale up to a defined network. Here we pursue instead the minimal artificial system based on the essential biological components-ion channels and lipid bilayers-where action potentials can be generated, propagated, and eventually networked. The fundamental unit is the classic supported bilayer: a planar bilayer patch with embedded ion channels in a fluidic environment where an ionic gradient is imposed across the bilayer. Two such units electrically connected form the basic building block for a network. The system is minimal in that we demonstrate that one kind of ion channel and correspondingly a gradient of only one ionic species is sufficient to generate an excitable system which shows amplification and threshold behavior. PMID:27049652

  17. Documents from malicious terminals

    NASA Astrophysics Data System (ADS)

    Berta, Istvan Z.; Vajda, Istvan

    2003-04-01

    The user wishes to communicate with a remote partner over an insecure network. Since the user is a human being, a terminal is needed for communication. Cryptographic algorithms running on the terminal may provide authenticity for the user's messages. In this paper the problem of sending authentic messages from insecure or untrusted terminals is analyzed. In this case attackers are able to gain total control over the terminal, so the user must consider the terminal a potential attacker. Smart cards are often considered the ultimate tool for secure messaging from untrusted terminals. However, their lack of user interface enables man-in-the middle attack from the terminal. The authors assume, that user is a human being with limited memory and computational power, and also makes mistakes in his calculations. They demnostrate, that only exceptional useres are able to authenticate messages without a trusted device. Several biometric media encapsulate the content of the message and the identity of the sender, such as speech, video and handwriting. The authors suggest, that such media is far more difficult to counterfeit than plaintext. Thus, the user must rely on his other resources, like biometric ones. In the protocol proposed by the authors, the user sends messages in a biometric format, strengthened by simple algorithmic authenticators. The smart card functions as a secure time gate ensuring, that the attacker has extremely little time to counterfeit both the biometric and the algorithmic protection on the message. The authors claim, that with the proper calibration of the biometric method and the time gate of the smart card, their protocol is strong enough for practical use.

  18. Malicious masquerade: myxoid melanoma.

    PubMed

    Hitchcock, M G; White, W L

    1998-08-01

    The morphological spectrum of malignant melanoma is broad. Unusual stromal changes can distract pathologists from the correct diagnosis. Fibroblastic, chondroid, osteoid, and myxoid stroma have been documented in melanomas. Myxoid melanoma is problematic--introducing carcinomas and soft tissue sarcomas into the differential diagnosis. This review examines the clinicopathologic aspects of myxoid malignant melanoma, with emphasis on its differential diagnosis. PMID:9711669

  19. Minimally Invasive Valve Surgery

    PubMed Central

    Pope, Nicolas H.; Ailawadi, Gorav

    2014-01-01

    Cardiac valve surgery is life saving for many patients. The advent of minimally invasive surgical techniques has historically allowed for improvement in both post-operative convalescence and important clinical outcomes. The development of minimally invasive cardiac valve repair and replacement surgery over the past decade is poised to revolutionize the care of cardiac valve patients. Here, we present a review of the history and current trends in minimally invasive aortic and mitral valve repair and replacement, including the development of sutureless bioprosthetic valves. PMID:24797148

  20. Prostate resection - minimally invasive

    MedlinePlus

    ... are: Erection problems (impotence) No symptom improvement Passing semen back into your bladder instead of out through ... Whelan JP, Goeree L. Systematic review and meta-analysis of transurethral resection of the prostate versus minimally ...

  1. Minimizing Shortness of Breath

    MedlinePlus

    ... Top Doctors in the Nation Departments & Divisions Home Health Insights Stress & Relaxation Breathing and Relaxation Minimizing Shortness of Breath ... Management Assess Your Stress Coping Strategies Identifying ... & Programs Health Insights Doctors & Departments Research & Science Education & Training Make ...

  2. Minimalism. Clip and Save.

    ERIC Educational Resources Information Center

    Hubbard, Guy

    2002-01-01

    Provides background information on the art movement called "Minimalism" discussing why it started and its characteristics. Includes learning activities and information on the artist, Donald Judd. Includes a reproduction of one of his art works and discusses its content. (CMK)

  3. Minimal Orderings Revisited

    SciTech Connect

    Peyton, B.W.

    1999-07-01

    When minimum orderings proved too difficult to deal with, Rose, Tarjan, and Leuker instead studied minimal orderings and how to compute them (Algorithmic aspects of vertex elimination on graphs, SIAM J. Comput., 5:266-283, 1976). This paper introduces an algorithm that is capable of computing much better minimal orderings much more efficiently than the algorithm in Rose et al. The new insight is a way to use certain structures and concepts from modern sparse Cholesky solvers to re-express one of the basic results in Rose et al. The new algorithm begins with any initial ordering and then refines it until a minimal ordering is obtained. it is simple to obtain high-quality low-cost minimal orderings by using fill-reducing heuristic orderings as initial orderings for the algorithm. We examine several such initial orderings in some detail.

  4. Minimally invasive hip replacement

    MedlinePlus

    ... Smits SA, Swinford RR, Bahamonde RE. A randomized, prospective study of 3 minimally invasive surgical approaches in total hip arthroplasty: comprehensive gait analysis. J Arthroplasty . 2008;23:68-73. PMID: 18722305 ...

  5. Minimally invasive procedures

    PubMed Central

    Baltayiannis, Nikolaos; Michail, Chandrinos; Lazaridis, George; Anagnostopoulos, Dimitrios; Baka, Sofia; Mpoukovinas, Ioannis; Karavasilis, Vasilis; Lampaki, Sofia; Papaiwannou, Antonis; Karavergou, Anastasia; Kioumis, Ioannis; Pitsiou, Georgia; Katsikogiannis, Nikolaos; Tsakiridis, Kosmas; Rapti, Aggeliki; Trakada, Georgia; Zissimopoulos, Athanasios; Zarogoulidis, Konstantinos

    2015-01-01

    Minimally invasive procedures, which include laparoscopic surgery, use state-of-the-art technology to reduce the damage to human tissue when performing surgery. Minimally invasive procedures require small “ports” from which the surgeon inserts thin tubes called trocars. Carbon dioxide gas may be used to inflate the area, creating a space between the internal organs and the skin. Then a miniature camera (usually a laparoscope or endoscope) is placed through one of the trocars so the surgical team can view the procedure as a magnified image on video monitors in the operating room. Specialized equipment is inserted through the trocars based on the type of surgery. There are some advanced minimally invasive surgical procedures that can be performed almost exclusively through a single point of entry—meaning only one small incision, like the “uniport” video-assisted thoracoscopic surgery (VATS). Not only do these procedures usually provide equivalent outcomes to traditional “open” surgery (which sometimes require a large incision), but minimally invasive procedures (using small incisions) may offer significant benefits as well: (I) faster recovery; (II) the patient remains for less days hospitalized; (III) less scarring and (IV) less pain. In our current mini review we will present the minimally invasive procedures for thoracic surgery. PMID:25861610

  6. Minimally Invasive Radiofrequency Devices.

    PubMed

    Sadick, Neil; Rothaus, Kenneth O

    2016-07-01

    This article reviews minimally invasive radiofrequency options for skin tightening, focusing on describing their mechanism of action and clinical profile in terms of safety and efficacy and presenting peer-reviewed articles associated with the specific technologies. Treatments offered by minimally invasive radiofrequency devices (fractional, microneedling, temperature-controlled) are increasing in popularity due to the dramatic effects they can have without requiring skin excision, downtime, or even extreme financial burden from the patient's perspective. Clinical applications thus far have yielded impressive results in treating signs of the aging face and neck, either as stand-alone or as postoperative maintenance treatments. PMID:27363771

  7. Ways To Minimize Bullying.

    ERIC Educational Resources Information Center

    Mueller, Mary Ellen; Parisi, Mary Joy

    This report delineates a series of interventions aimed at minimizing incidences of bullying in a suburban elementary school. The social services staff was scheduled to initiate an anti-bullying incentive in fall 2001 due to the increased occurrences of bullying during the prior year. The target population consisted of third- and fourth-grade…

  8. Periodic minimal surfaces

    NASA Astrophysics Data System (ADS)

    Mackay, Alan L.

    1985-04-01

    A minimal surface is one for which, like a soap film with the same pressure on each side, the mean curvature is zero and, thus, is one where the two principal curvatures are equal and opposite at every point. For every closed circuit in the surface, the area is a minimum. Schwarz1 and Neovius2 showed that elements of such surfaces could be put together to give surfaces periodic in three dimensions. These periodic minimal surfaces are geometrical invariants, as are the regular polyhedra, but the former are curved. Minimal surfaces are appropriate for the description of various structures where internal surfaces are prominent and seek to adopt a minimum area or a zero mean curvature subject to their topology; thus they merit more complete numerical characterization. There seem to be at least 18 such surfaces3, with various symmetries and topologies, related to the crystallographic space groups. Recently, glyceryl mono-oleate (GMO) was shown by Longley and McIntosh4 to take the shape of the F-surface. The structure postulated is shown here to be in good agreement with an analysis of the fundamental geometry of periodic minimal surfaces.

  9. The Minimal Era

    ERIC Educational Resources Information Center

    Van Ness, Wilhelmina

    1974-01-01

    Described the development of Minimal Art, a composite name that has been applied to the scattering of bland, bleak, non-objective fine arts painting and sculpture forms that proliferated slightly mysteriously in the middle 1960's as Pop Art began to decline. (Author/RK)

  10. Minimally invasive pancreatic surgery.

    PubMed

    Yiannakopoulou, E

    2015-12-01

    Minimally invasive pancreatic surgery is feasible and safe. Laparoscopic distal pancreatectomy should be widely adopted for benign lesions of the pancreas. Laparoscopic pancreaticoduodenectomy, although technically demanding, in the setting of pancreatic ductal adenocarcinoma has a number of advantages including shorter hospital stay, faster recovery, allowing patients to recover in a timelier manner and pursue adjuvant treatment options. Furthermore, it seems that progression-free survival is longer in patients undergoing laparoscopic pancreaticoduodenectomy in comparison with those undergoing open pancreaticoduodenectomy. Minimally invasive middle pancreatectomy seems appropriate for benign or borderline tumors of the neck of the pancreas. Technological advances including intraoperative ultrasound and intraoperative fluorescence imaging systems are expected to facilitate the wide adoption of minimally invasive pancreatic surgery. Although, the oncological outcome seems similar with that of open surgery, there are still concerns, as the majority of relevant evidence comes from retrospective studies. Large multicenter randomized studies comparing laparoscopic with open pancreatectomy as well as robotic assisted with both open and laparoscopic approaches are needed. Robotic approach could be possibly shown to be less invasive than conventional laparoscopic approach through the less traumatic intra-abdominal handling of tissues. In addition, robotic approach could enable the wide adoption of the technique by surgeon who is not that trained in advanced laparoscopic surgery. A putative clinical benefit of minimally invasive pancreatic surgery could be the attenuated surgical stress response leading to reduced morbidity and mortality as well as lack of the detrimental immunosuppressive effect especially for the oncological patients. PMID:26530291

  11. Non-minimal Inflationary Attractors

    SciTech Connect

    Kallosh, Renata; Linde, Andrei E-mail: alinde@stanford.edu

    2013-10-01

    Recently we identified a new class of (super)conformally invariant theories which allow inflation even if the scalar potential is very steep in terms of the original conformal variables. Observational predictions of a broad class of such theories are nearly model-independent. In this paper we consider generalized versions of these models where the inflaton has a non-minimal coupling to gravity with a negative parameter ξ different from its conformal value -1/6. We show that these models exhibit attractor behavior. With even a slight increase of |ξ| from |ξ| = 0, predictions of these models for n{sub s} and r rapidly converge to their universal model-independent values corresponding to conformal coupling ξ = −1/6. These values of n{sub s} and r practically coincide with the corresponding values in the limit ξ → −∞.

  12. Minimally invasive radioguided parathyroidectomy.

    PubMed

    Costello, D; Norman, J

    1999-07-01

    The last decade has been characterized by an emphasis on minimizing interventional techniques, hospital stays, and overall costs of patient care. It is clear that most patients with sporadic HPT do not require a complete neck exploration. We now know that a minimal approach is appropriate for this disease. Importantly, the MIRP technique can be applied to most patients with sporadic HPT and can be performed by surgeons with modest advanced training. The use of a gamma probe as a surgical tool converts the sestamibi to a functional and anatomical scan eliminating the need for any other preoperative localizing study. Quantification of the radioactivity within the removed gland eliminates the need for routine frozen section histologic examination and obviates the need for costly intraoperative parathyroid hormone measurements. This radioguided technique allows the benefit of local anesthesia, dramatically reduces operative times, eliminates postoperative blood tests, provides a smaller scar, requires minimal time spent in the hospital, and almost assures a rapid, near pain-free recovery. This combination is beneficial to the patient whereas helping achieve a reduction in overall costs. PMID:10448697

  13. Waste Minimization Crosscut Plan

    SciTech Connect

    Not Available

    1992-05-13

    On November 27, 1991, the Secretary of Energy directed that a Department of Energy (DOE) crosscut plan for waste minimization (WMin) be prepared and submitted by March 1, 1992. This Waste Minimization Crosscut Plan responds to the Secretary`s direction and supports the National Energy Strategy (NES) goals of achieving greater energy security, increasing energy and economic efficiency, and enhancing environmental quality. It provides a DOE-wide planning framework for effective coordination of all DOE WMin activities. This Plan was jointly prepared by the following Program Secretarial Officer (PSO) organizations: Civilian Radioactive Waste Management (RW); Conservation and Renewable Energy (CE); Defense Programs (DP); Environmental Restoration and Waste Management (EM), lead; Energy Research (ER); Fossil Energy (FE); Nuclear Energy (NE); and New Production Reactors (NP). Assistance and guidance was provided by the offices of Policy, Planning, and Analysis (PE) and Environment, Safety and Health (EH). Comprehensive application of waste minimization within the Department and in both the public and private sectors will provide significant benefits and support National Energy Strategy goals. These benefits include conservation of a substantial proportion of the energy now used by industry and Government, improved environmental quality, reduced health risks, improved production efficiencies, and longer useful life of disposal capacity. Taken together, these benefits will mean improved US global competitiveness, expanded job opportunities, and a better quality of life for all citizens.

  14. Minimally invasive mediastinal surgery.

    PubMed

    Melfi, Franca M A; Fanucchi, Olivia; Mussi, Alfredo

    2016-01-01

    In the past, mediastinal surgery was associated with the necessity of a maximum exposure, which was accomplished through various approaches. In the early 1990s, many surgical fields, including thoracic surgery, observed the development of minimally invasive techniques. These included video-assisted thoracic surgery (VATS), which confers clear advantages over an open approach, such as less trauma, short hospital stay, increased cosmetic results and preservation of lung function. However, VATS is associated with several disadvantages. For this reason, it is not routinely performed for resection of mediastinal mass lesions, especially those located in the anterior mediastinum, a tiny and remote space that contains vital structures at risk of injury. Robotic systems can overcome the limits of VATS, offering three-dimensional (3D) vision and wristed instrumentations, and are being increasingly used. With regards to thymectomy for myasthenia gravis (MG), unilateral and bilateral VATS approaches have demonstrated good long-term neurologic results with low complication rates. Nevertheless, some authors still advocate the necessity of maximum exposure, especially when considering the distribution of normal and ectopic thymic tissue. In recent studies, the robotic approach has shown to provide similar neurological outcomes when compared to transsternal and VATS approaches, and is associated with a low morbidity. Importantly, through a unilateral robotic technique, it is possible to dissect and remove at least the same amount of mediastinal fat tissue. Preliminary results on early-stage thymomatous disease indicated that minimally invasive approaches are safe and feasible, with a low rate of pleural recurrence, underlining the necessity of a "no-touch" technique. However, especially for thymomatous disease characterized by an indolent nature, further studies with long follow-up period are necessary in order to assess oncologic and neurologic results through minimally invasive

  15. Minimally invasive mediastinal surgery

    PubMed Central

    Melfi, Franca M. A.; Mussi, Alfredo

    2016-01-01

    In the past, mediastinal surgery was associated with the necessity of a maximum exposure, which was accomplished through various approaches. In the early 1990s, many surgical fields, including thoracic surgery, observed the development of minimally invasive techniques. These included video-assisted thoracic surgery (VATS), which confers clear advantages over an open approach, such as less trauma, short hospital stay, increased cosmetic results and preservation of lung function. However, VATS is associated with several disadvantages. For this reason, it is not routinely performed for resection of mediastinal mass lesions, especially those located in the anterior mediastinum, a tiny and remote space that contains vital structures at risk of injury. Robotic systems can overcome the limits of VATS, offering three-dimensional (3D) vision and wristed instrumentations, and are being increasingly used. With regards to thymectomy for myasthenia gravis (MG), unilateral and bilateral VATS approaches have demonstrated good long-term neurologic results with low complication rates. Nevertheless, some authors still advocate the necessity of maximum exposure, especially when considering the distribution of normal and ectopic thymic tissue. In recent studies, the robotic approach has shown to provide similar neurological outcomes when compared to transsternal and VATS approaches, and is associated with a low morbidity. Importantly, through a unilateral robotic technique, it is possible to dissect and remove at least the same amount of mediastinal fat tissue. Preliminary results on early-stage thymomatous disease indicated that minimally invasive approaches are safe and feasible, with a low rate of pleural recurrence, underlining the necessity of a “no-touch” technique. However, especially for thymomatous disease characterized by an indolent nature, further studies with long follow-up period are necessary in order to assess oncologic and neurologic results through minimally

  16. The ZOOM minimization package

    SciTech Connect

    Fischler, Mark S.; Sachs, D.; /Fermilab

    2004-11-01

    A new object-oriented Minimization package is available for distribution in the same manner as CLHEP. This package, designed for use in HEP applications, has all the capabilities of Minuit, but is a re-write from scratch, adhering to modern C++ design principles. A primary goal of this package is extensibility in several directions, so that its capabilities can be kept fresh with as little maintenance effort as possible. This package is distinguished by the priority that was assigned to C++ design issues, and the focus on producing an extensible system that will resist becoming obsolete.

  17. Minimally Invasive Parathyroidectomy

    PubMed Central

    Starker, Lee F.; Fonseca, Annabelle L.; Carling, Tobias; Udelsman, Robert

    2011-01-01

    Minimally invasive parathyroidectomy (MIP) is an operative approach for the treatment of primary hyperparathyroidism (pHPT). Currently, routine use of improved preoperative localization studies, cervical block anesthesia in the conscious patient, and intraoperative parathyroid hormone analyses aid in guiding surgical therapy. MIP requires less surgical dissection causing decreased trauma to tissues, can be performed safely in the ambulatory setting, and is at least as effective as standard cervical exploration. This paper reviews advances in preoperative localization, anesthetic techniques, and intraoperative management of patients undergoing MIP for the treatment of pHPT. PMID:21747851

  18. Minimally refined biomass fuel

    DOEpatents

    Pearson, Richard K.; Hirschfeld, Tomas B.

    1984-01-01

    A minimally refined fluid composition, suitable as a fuel mixture and derived from biomass material, is comprised of one or more water-soluble carbohydrates such as sucrose, one or more alcohols having less than four carbons, and water. The carbohydrate provides the fuel source; water solubilizes the carbohydrates; and the alcohol aids in the combustion of the carbohydrate and reduces the vicosity of the carbohydrate/water solution. Because less energy is required to obtain the carbohydrate from the raw biomass than alcohol, an overall energy savings is realized compared to fuels employing alcohol as the primary fuel.

  19. Wake Vortex Minimization

    NASA Technical Reports Server (NTRS)

    1977-01-01

    A status report is presented on research directed at reducing the vortex disturbances of aircraft wakes. The objective of such a reduction is to minimize the hazard to smaller aircraft that might encounter these wakes. Inviscid modeling was used to study trailing vortices and viscous effects were investigated. Laser velocimeters were utilized in the measurement of aircraft wakes. Flight and wind tunnel tests were performed on scale and full model scale aircraft of various design. Parameters investigated included the effect of wing span, wing flaps, spoilers, splines and engine thrust on vortex attenuation. Results indicate that vortives may be alleviated through aerodynamic means.

  20. Minimizing hazardous waste

    SciTech Connect

    DeClue, S.C.

    1996-06-01

    Hazardous waste minimization is a broad term often associated with pollution prevention, saving the environment or protecting Mother Earth. Some associate hazardous waste minimization with saving money. Thousands of hazardous materials are used in processes every day, but when these hazardous materials become hazardous wastes, dollars must be spent for disposal. When hazardous waste is reduced, an organization will spend less money on hazardous waste disposal. In 1993, Fort Bragg reduced its hazardous waste generation by over 100,000 pounds and spent nearly $90,000 less on hazardous waste disposal costs than in 1992. Fort Bragg generates a variety of wastes: Vehicle maintenance wastes such as antifreeze, oil, grease and solvents; helicopter maintenance wastes, including solvents, adhesives, lubricants and paints; communication operation wastes such as lithium, magnesium, mercury and nickel-cadmium batteries; chemical defense wastes detection, decontamination, and protective mask filters. The Hazardous Waste Office has the responsibility to properly identify, characterize, classify and dispose of these waste items in accordance with US Environmental Protection Agency (EPA) and US Department of Transportation (DOT) regulations.

  1. Safeguarding Rights, Minimizing Exposure.

    ERIC Educational Resources Information Center

    Essex, Nathan L.

    1999-01-01

    School officials have a moral and legal duty to preserve all students' safety and well-being while not trampling on the constitutional rights of students involved in disruptive behavior. Administrators must adopt defensible school policies, ensure parent understanding, observe due process, and exercise administrative authority in a reasonable…

  2. Minimal noise subsystems

    NASA Astrophysics Data System (ADS)

    Wang, Xiaoting; Byrd, Mark; Jacobs, Kurt

    2016-03-01

    A system subjected to noise contains a decoherence-free subspace or subsystem (DFS) only if the noise possesses an exact symmetry. Here we consider noise models in which a perturbation breaks a symmetry of the noise, so that if S is a DFS under a given noise process it is no longer so under the new perturbed noise process. We ask whether there is a subspace or subsystem that is more robust to the perturbed noise than S . To answer this question we develop a numerical method that allows us to search for subspaces or subsystems that are maximally robust to arbitrary noise processes. We apply this method to a number of examples, and find that a subsystem that is a DFS is often not the subsystem that experiences minimal noise when the symmetry of the noise is broken by a perturbation. We discuss which classes of noise have this property.

  3. Minimal quiver standard model

    SciTech Connect

    Berenstein, David; Pinansky, Samuel

    2007-05-01

    This paper discusses the minimal quiver gauge theory embedding of the standard model that could arise from brane world type string theory constructions. It is based on the low energy effective field theory of D branes in the perturbative regime. The model differs from the standard model by the addition of one extra massive gauge boson, and contains only one additional parameter to the standard model: the mass of this new particle. The coupling of this new particle to the standard model is uniquely determined by input from the standard model and consistency conditions of perturbative string theory. We also study some aspects of the phenomenology of this model and bounds on its possible observation at the Large Hadron Collider.

  4. [Minimally invasive breast surgery].

    PubMed

    Mátrai, Zoltán; Gulyás, Gusztáv; Kunos, Csaba; Sávolt, Akos; Farkas, Emil; Szollár, András; Kásler, Miklós

    2014-02-01

    Due to the development in medical science and industrial technology, minimally invasive procedures have appeared in the surgery of benign and malignant breast diseases. In general , such interventions result in significantly reduced breast and chest wall scars, shorter hospitalization and less pain, but they require specific, expensive devices, longer surgical time compared to open surgery. Furthermore, indications or oncological safety have not been established yet. It is quite likely, that minimally invasive surgical procedures with high-tech devices - similar to other surgical subspecialties -, will gradually become popular and it may form part of routine breast surgery even. Vacuum-assisted core biopsy with a therapeutic indication is suitable for the removal of benign fibroadenomas leaving behind an almost invisible scar, while endoscopically assisted skin-sparing and nipple-sparing mastectomy, axillary staging and reconstruction with latissimus dorsi muscle flap are all feasible through the same short axillary incision. Endoscopic techniques are also suitable for the diagnostics and treatment of intracapsular complications of implant-based breast reconstructions (intracapsular fluid, implant rupture, capsular contracture) and for the biopsy of intracapsular lesions with uncertain pathology. Perception of the role of radiofrequency ablation of breast tumors requires further hands-on experience, but it is likely that it can serve as a replacement of surgical removal in a portion of primary tumors in the future due to the development in functional imaging and anticancer drugs. With the reduction of the price of ductoscopes routine examination of the ductal branch system, guided microdochectomy and targeted surgical removal of terminal ducto-lobular units or a "sick lobe" as an anatomical unit may become feasible. The paper presents the experience of the authors and provides a literature review, for the first time in Hungarian language on the subject. Orv. Hetil

  5. Minimally invasive parathyroid surgery

    PubMed Central

    Noureldine, Salem I.; Gooi, Zhen

    2015-01-01

    Traditionally, bilateral cervical exploration for localization of all four parathyroid glands and removal of any that are grossly enlarged has been the standard surgical treatment for primary hyperparathyroidism (PHPT). With the advances in preoperative localization studies and greater public demand for less invasive procedures, novel targeted, minimally invasive techniques to the parathyroid glands have been described and practiced over the past 2 decades. Minimally invasive parathyroidectomy (MIP) can be done either through the standard Kocher incision, a smaller midline incision, with video assistance (purely endoscopic and video-assisted techniques), or through an ectopically placed, extracervical, incision. In current practice, once PHPT is diagnosed, preoperative evaluation using high-resolution radiographic imaging to localize the offending parathyroid gland is essential if MIP is to be considered. The imaging study results suggest where the surgeon should begin the focused procedure and serve as a road map to allow tailoring of an efficient, imaging-guided dissection while eliminating the unnecessary dissection of multiple glands or a bilateral exploration. Intraoperative parathyroid hormone (IOPTH) levels may be measured during the procedure, or a gamma probe used during radioguided parathyroidectomy, to ascertain that the correct gland has been excised and that no other hyperfunctional tissue is present. MIP has many advantages over the traditional bilateral, four-gland exploration. MIP can be performed using local anesthesia, requires less operative time, results in fewer complications, and offers an improved cosmetic result and greater patient satisfaction. Additional advantages of MIP are earlier hospital discharge and decreased overall associated costs. This article aims to address the considerations for accomplishing MIP, including the role of preoperative imaging studies, intraoperative adjuncts, and surgical techniques. PMID:26425454

  6. Minimal Marking: A Success Story

    ERIC Educational Resources Information Center

    McNeilly, Anne

    2014-01-01

    The minimal-marking project conducted in Ryerson's School of Journalism throughout 2012 and early 2013 resulted in significantly higher grammar scores in two first-year classes of minimally marked university students when compared to two traditionally marked classes. The "minimal-marking" concept (Haswell, 1983), which requires…

  7. Swarm robotics and minimalism

    NASA Astrophysics Data System (ADS)

    Sharkey, Amanda J. C.

    2007-09-01

    Swarm Robotics (SR) is closely related to Swarm Intelligence, and both were initially inspired by studies of social insects. Their guiding principles are based on their biological inspiration and take the form of an emphasis on decentralized local control and communication. Earlier studies went a step further in emphasizing the use of simple reactive robots that only communicate indirectly through the environment. More recently SR studies have moved beyond these constraints to explore the use of non-reactive robots that communicate directly, and that can learn and represent their environment. There is no clear agreement in the literature about how far such extensions of the original principles could go. Should there be any limitations on the individual abilities of the robots used in SR studies? Should knowledge of the capabilities of social insects lead to constraints on the capabilities of individual robots in SR studies? There is a lack of explicit discussion of such questions, and researchers have adopted a variety of constraints for a variety of reasons. A simple taxonomy of swarm robotics is presented here with the aim of addressing and clarifying these questions. The taxonomy distinguishes subareas of SR based on the emphases and justifications for minimalism and individual simplicity.

  8. Minimal distances between SCFTs

    NASA Astrophysics Data System (ADS)

    Buican, Matthew

    2014-01-01

    We study lower bounds on the minimal distance in theory space between four-dimensional superconformal field theories (SCFTs) connected via broad classes of renormalization group (RG) flows preserving various amounts of supersymmetry (SUSY). For = 1 RG flows, the ultraviolet (UV) and infrared (IR) endpoints of the flow can be parametrically close. On the other hand, for RG flows emanating from a maximally supersymmetric SCFT, the distance to the IR theory cannot be arbitrarily small regardless of the amount of (non-trivial) SUSY preserved along the flow. The case of RG flows from =2 UV SCFTs is more subtle. We argue that for RG flows preserving the full =2 SUSY, there are various obstructions to finding examples with parametrically close UV and IR endpoints. Under reasonable assumptions, these obstructions include: unitarity, known bounds on the c central charge derived from associativity of the operator product expansion, and the central charge bounds of Hofman and Maldacena. On the other hand, for RG flows that break = 2 → = 1, it is possible to find IR fixed points that are parametrically close to the UV ones. In this case, we argue that if the UV SCFT possesses a single stress tensor, then such RG flows excite of order all the degrees of freedom of the UV theory. Furthermore, if the UV theory has some flavor symmetry, we argue that the UV central charges should not be too large relative to certain parameters in the theory.

  9. Minimal Higgs inflation

    NASA Astrophysics Data System (ADS)

    Hamada, Yuta; Kawai, Hikaru; Oda, Kin-ya

    2014-02-01

    We consider a possibility that the Higgs field in the Standard Model (SM) serves as an inflaton when its value is around the Planck scale. We assume that the SM is valid up to an ultraviolet cutoff scale Λ , which is slightly below the Planck scale, and that the Higgs potential becomes almost flat above Λ . Contrary to the ordinary Higgs inflation scenario, we do not assume the huge non-minimal coupling, of O(10^4), of the Higgs field to the Ricci scalar. We find that Λ must be less than 5× 10^{17} {GeV} in order to explain the observed fluctuation of the cosmic microwave background, no matter how we extrapolate the Higgs potential above Λ . The scale 10^{17} {GeV} coincides with the perturbative string scale, which suggests that the SM is directly connected with string theory. For this to be true, the top quark mass is restricted to around 171 GeV, with which Λ can exceed 10^{17} {GeV}. As a concrete example of the potential above Λ , we propose a simple log-type potential. The predictions of this specific model for the e-foldings N_*=50-60 are consistent with the current observation, namely, the scalar spectral index is n_s=0.977hbox {-}0.983 and the tensor to scalar ratio 0

  10. Influenza SIRS with Minimal Pneumonitis

    PubMed Central

    Erramilli, Shruti; Mannam, Praveen; Manthous, Constantine A.

    2016-01-01

    Although systemic inflammatory response syndrome (SIRS) is a known complication of severe influenza pneumonia, it has been reported very rarely in patients with minimal parenchymal lung disease. We here report a case of severe SIRS, anasarca, and marked vascular phenomena with minimal or no pneumonitis. This case highlights that viruses, including influenza, may cause vascular dysregulation causing SIRS, even without substantial visceral organ involvement.

  11. Guidelines for mixed waste minimization

    SciTech Connect

    Owens, C.

    1992-02-01

    Currently, there is no commercial mixed waste disposal available in the United States. Storage and treatment for commercial mixed waste is limited. Host States and compacts region officials are encouraging their mixed waste generators to minimize their mixed wastes because of management limitations. This document provides a guide to mixed waste minimization.

  12. Waste minimization handbook, Volume 1

    SciTech Connect

    Boing, L.E.; Coffey, M.J.

    1995-12-01

    This technical guide presents various methods used by industry to minimize low-level radioactive waste (LLW) generated during decommissioning and decontamination (D and D) activities. Such activities generate significant amounts of LLW during their operations. Waste minimization refers to any measure, procedure, or technique that reduces the amount of waste generated during a specific operation or project. Preventive waste minimization techniques implemented when a project is initiated can significantly reduce waste. Techniques implemented during decontamination activities reduce the cost of decommissioning. The application of waste minimization techniques is not limited to D and D activities; it is also useful during any phase of a facility`s life cycle. This compendium will be supplemented with a second volume of abstracts of hundreds of papers related to minimizing low-level nuclear waste. This second volume is expected to be released in late 1996.

  13. Minimal relativistic three-particle equations

    SciTech Connect

    Lindesay, J.

    1981-07-01

    A minimal self-consistent set of covariant and unitary three-particle equations is presented. Numerical results are obtained for three-particle bound states, elastic scattering and rearrangement of bound pairs with a third particle, and amplitudes for breakup into states of three free particles. The mathematical form of the three-particle bound state equations is explored; constraints are set upon the range of eigenvalues and number of eigenstates of these one parameter equations. The behavior of the number of eigenstates as the two-body binding energy decreases to zero in a covariant context generalizes results previously obtained non-relativistically by V. Efimov.

  14. The minimal length and quantum partition functions

    NASA Astrophysics Data System (ADS)

    Abbasiyan-Motlaq, M.; Pedram, P.

    2014-08-01

    We study the thermodynamics of various physical systems in the framework of the generalized uncertainty principle that implies a minimal length uncertainty proportional to the Planck length. We present a general scheme to analytically calculate the quantum partition function of the physical systems to first order of the deformation parameter based on the behavior of the modified energy spectrum and compare our results with the classical approach. Also, we find the modified internal energy and heat capacity of the systems for the anti-Snyder framework.

  15. Flocking with minimal cooperativity: The panic model

    NASA Astrophysics Data System (ADS)

    Pilkiewicz, Kevin R.; Eaves, Joel D.

    2014-01-01

    We present a two-dimensional lattice model of self-propelled spins that can change direction only upon collision with another spin. We show that even with ballistic motion and minimal cooperativity, these spins display robust flocking behavior at nearly all densities, forming long bands of stripes. The structural transition in this system is not a thermodynamic phase transition, but it can still be characterized by an order parameter, and we demonstrate that if this parameter is studied as a dynamical variable rather than a steady-state observable, we can extract a detailed picture of how the flocking mechanism varies with density.

  16. Minimizing waste in environmental restoration

    SciTech Connect

    Moos, L.; Thuot, J.R.

    1996-07-01

    Environmental restoration, decontamination and decommissioning and facility dismantelment projects are not typically known for their waste minimization and pollution prevention efforts. Typical projects are driven by schedules and milestones with little attention given to cost or waste minimization. Conventional wisdom in these projects is that the waste already exists and cannot be reduced or minimized. In fact, however, there are three significant areas where waste and cost can be reduced. Waste reduction can occur in three ways: beneficial reuse or recycling; segregation of waste types; and reducing generation of secondary waste. This paper will discuss several examples of reuse, recycle, segregation, and secondary waste reduction at ANL restoration programs.

  17. Minimization In Digital Design As A Meta-Planning Problem

    NASA Astrophysics Data System (ADS)

    Ho, William P. C.; Wu, Jung-Gen

    1987-05-01

    In our model-based expert system for automatic digital system design, we formalize the design process into three sub-processes - compiling high-level behavioral specifications into primitive behavioral operations, grouping primitive operations into behavioral functions, and grouping functions into modules. Consideration of design minimization explicitly controls decision-making in the last two subprocesses. Design minimization, a key task in the automatic design of digital systems, is complicated by the high degree of interaction among the time sequence and content of design decisions. In this paper, we present an AI approach which directly addresses these interactions and their consequences by modeling the minimization prob-lem as a planning problem, and the management of design decision-making as a meta-planning problem.

  18. Heart bypass surgery - minimally invasive

    MedlinePlus

    ... in 30-day outcomes in high-risk patients randomized to off-pump versus on-pump coronary bypass ... Thiele H, Neumann-Schniedewind P, Jacobs S, et al. Randomized comparison of minimally invasive direct coronary artery bypass ...

  19. Mitral valve surgery - minimally invasive

    MedlinePlus

    ... that does many of these procedures. Minimally invasive heart valve surgery has improved greatly in recent years. These ... WT, Mack MJ. Transcatheter cardiac valve interventions. Surg Clin North Am . 2009;89:951-66. ...

  20. Minimizing pollutants with multimedia strategies

    SciTech Connect

    Phillips, J.B.; Hindawi, M.A.

    1997-01-01

    A multimedia approach to pollution prevention that focuses on minimizing or eliminating production of pollutants is one of the most advantageous strategies to adopt in preparing an overall facility environmental plan. If processes are optimized to preclude or minimize the manufacture of streams containing pollutants, or to reduce the levels of pollutants in waste streams, then the task of multimedia pollution prevention becomes more manageable simply as a result of a smaller problem needing to be addressed. An orderly and systematic approach to waste minimization can result in a comprehensive strategy to reduce the production of waste streams and simultaneously improve the profitability of a process or industrial operation. There are a number of miscellaneous strategies for a waste minimization that attack the problem via process chemistry or engineering. Examples include installation of low-NO{sub x} burners, selection of valves that minimize fugitive emissions, high-level switches on storage tanks, the use of in-plant stills for recycling and reusing solvents and using water-based products instead of hydrocarbon-based products wherever possible. Other waste minimization countermeasures can focus on O and M issues.

  1. Free energies for singleton minimal states

    NASA Astrophysics Data System (ADS)

    Golden, J. M.

    2016-06-01

    It is assumed that any free energy function exhibits strict periodic behavior for histories that have been periodic for all past times. This is not the case for the work function, which, however, has the usual defining properties of a free energy. Forms given in fairly recent years for the minimum and related free energies of linear materials with memory have this property. Materials for which the minimal states are all singletons are those for which at least some of the singularities of the Fourier transform of the relaxation function are not isolated. For such materials, the maximum free energy is the work function, and free energies intermediate between the minimum free energy and the work function should be given by a linear relation involving these two quantities. All such functionals, except the minimum free energy, therefore do not have strict periodic behavior for periodic histories, which contradicts our assumption. A way out of the difficulty is explored which involves approximating the relaxation function by a form for which the minimal states are no longer singletons. A representation can then be given of an arbitrary free energy as a linear combination of the minimum, maximum and intermediate free energies derived in earlier work. This representation obeys our periodicity assumption. Numerical data are presented, supporting the consistency of this approach.

  2. Probabilistic Characterization of Adversary Behavior in Cyber Security

    SciTech Connect

    Meyers, C A; Powers, S S; Faissol, D M

    2009-10-08

    The objective of this SMS effort is to provide a probabilistic characterization of adversary behavior in cyber security. This includes both quantitative (data analysis) and qualitative (literature review) components. A set of real LLNL email data was obtained for this study, consisting of several years worth of unfiltered traffic sent to a selection of addresses at ciac.org. The email data was subjected to three interrelated analyses: a textual study of the header data and subject matter, an examination of threats present in message attachments, and a characterization of the maliciousness of embedded URLs.

  3. Do chimpanzees (Pan troglodytes schweinfurthii) exhibit sleep related behaviors that minimize exposure to parasitic arthropods? A preliminary report on the possible anti-vector function of chimpanzee sleeping platforms.

    PubMed

    Samson, David R; Muehlenbein, Michael P; Hunt, Kevin D

    2013-01-01

    Great apes spend half of their lives in a nightly "nest" or sleeping platform (SP), a complex object created by modifying foliage, which functions as a stable substrate on which to sleep. Of the several purported functions of SPs, one hypothesis is that they protect against parasitic infection. Here we investigate the role of SP site choice in avoiding molestation by arthropods. This study presents preliminary data on the insect-repellent properties of preferred sleeping tree species Cynometra alexandri. Insect traps were deployed in gallery forest habitats in which chimpanzees typically "nest." We compared traps placed adjacent to SPs artificially manufactured with C. alexandri trees to an open area within the same habitat. Multiple measures of arthropod counts indicate that simulated C. alexandri SP sites have fewer arthropods than similar non-SP sites. Volatile compounds secreted by C. alexandri foliage are hypothesized to repel annoying arthropods and/or mask chimpanzee olfactory signals. Of the total insects captured (n = 6,318), n = 145 were mosquitoes. Of the total mosquitoes captured, n = 47 were identified as Anopheles (female, n = 12). The prominent malarial vector Anopheles gambiae was identified among the captured mosquito sample. These results suggest that the presence of broken branches of the tree species C. alexandri reduce the amount of insects a chimpanzee is exposed to throughout a night's sleep. This great ape behavioral and socio-technological adaptation may have evolved, in part, to increase quality of sleep as well as decrease exposure to vectors of disease. PMID:23011513

  4. Incentives, Behavior, and Risk Management

    ERIC Educational Resources Information Center

    Liu, Debin

    2011-01-01

    Insiders are one of the most serious threats to an organization's information assets. Generally speaking, there are two types of insider threats based on the insiders' intents. Malicious Insiders are individuals with varying degrees of harmful intentions. Inadvertent Insiders are individuals without malicious intent. In this dissertation, I…

  5. Minimally invasive video-assisted versus minimally invasive nonendoscopic thyroidectomy.

    PubMed

    Fík, Zdeněk; Astl, Jaromír; Zábrodský, Michal; Lukeš, Petr; Merunka, Ilja; Betka, Jan; Chovanec, Martin

    2014-01-01

    Minimally invasive video-assisted thyroidectomy (MIVAT) and minimally invasive nonendoscopic thyroidectomy (MINET) represent well accepted and reproducible techniques developed with the main goal to improve cosmetic outcome, accelerate healing, and increase patient's comfort following thyroid surgery. Between 2007 and 2011, a prospective nonrandomized study of patients undergoing minimally invasive thyroid surgery was performed to compare advantages and disadvantages of the two different techniques. There were no significant differences in the length of incision to perform surgical procedures. Mean duration of hemithyroidectomy was comparable in both groups, but it was more time consuming to perform total thyroidectomy by MIVAT. There were more patients undergoing MIVAT procedures without active drainage in the postoperative course and we also could see a trend for less pain in the same group. This was paralleled by statistically significant decreased administration of both opiates and nonopiate analgesics. We encountered two cases of recurrent laryngeal nerve palsies in the MIVAT group only. MIVAT and MINET represent safe and feasible alternative to conventional thyroid surgery in selected cases and this prospective study has shown minimal differences between these two techniques. PMID:24800227

  6. The New Minimal Standard Model

    SciTech Connect

    Davoudiasl, Hooman; Kitano, Ryuichiro; Li, Tianjun; Murayama, Hitoshi

    2005-01-13

    We construct the New Minimal Standard Model that incorporates the new discoveries of physics beyond the Minimal Standard Model (MSM): Dark Energy, non-baryonic Dark Matter, neutrino masses, as well as baryon asymmetry and cosmic inflation, adopting the principle of minimal particle content and the most general renormalizable Lagrangian. We base the model purely on empirical facts rather than aesthetics. We need only six new degrees of freedom beyond the MSM. It is free from excessive flavor-changing effects, CP violation, too-rapid proton decay, problems with electroweak precision data, and unwanted cosmological relics. Any model of physics beyond the MSM should be measured against the phenomenological success of this model.

  7. LLNL Waste Minimization Program Plan

    SciTech Connect

    Not Available

    1990-02-14

    This document is the February 14, 1990 version of the LLNL Waste Minimization Program Plan (WMPP). The Waste Minimization Policy field has undergone continuous changes since its formal inception in the 1984 HSWA legislation. The first LLNL WMPP, Revision A, is dated March 1985. A series of informal revision were made on approximately a semi-annual basis. This Revision 2 is the third formal issuance of the WMPP document. EPA has issued a proposed new policy statement on source reduction and recycling. This policy reflects a preventative strategy to reduce or eliminate the generation of environmentally-harmful pollutants which may be released to the air, land surface, water, or ground water. In accordance with this new policy new guidance to hazardous waste generators on the elements of a Waste Minimization Program was issued. In response to these policies, DOE has revised and issued implementation guidance for DOE Order 5400.1, Waste Minimization Plan and Waste Reduction reporting of DOE Hazardous, Radioactive, and Radioactive Mixed Wastes, final draft January 1990. This WMPP is formatted to meet the current DOE guidance outlines. The current WMPP will be revised to reflect all of these proposed changes when guidelines are established. Updates, changes and revisions to the overall LLNL WMPP will be made as appropriate to reflect ever-changing regulatory requirements. 3 figs., 4 tabs.

  8. WASTE MINIMIZATION OPPORTUNITY ASSESSMENT MANUAL

    EPA Science Inventory

    Waste minimization (WM) is a policy specifically mandated by the U.S. Congress in the 1984 Hazardous and Solid Wastes Amendments to the Resource Conservation and Recovery Act (RCRA). The RCRA regulations require that generators of hazardous waste have a program in place to reduce...

  9. Assembly of a minimal protocell

    NASA Astrophysics Data System (ADS)

    Rasmussen, Steen

    2007-03-01

    What is minimal life, how can we make it, and how can it be useful? We present experimental and computational results towards bridging nonliving and living matter, which results in life that is different and much simpler than contemporary life. A simple yet tightly coupled catalytic cooperation between genes, metabolism, and container forms the design underpinnings of our protocell, which is a minimal self-replicating molecular machine. Experimentally, we have recently demonstrated this coupling by having an informational molecule (8-oxoguanine) catalytically control the light driven metabolic (Ru-bpy based) production of container materials (fatty acids). This is a significant milestone towards assembling a minimal self-replicating molecular machine. Recent theoretical investigations indicate that coordinated exponential component growth should naturally emerge as a result from such a catalytic coupling between the main protocellular components. A 3-D dissipative particle simulation (DPD) study of the full protocell life-cycle exposes a number of anticipated systemic issues associated with the remaining experimental challenges for the implementation of the minimal protocell. Finally we outline how more general self-replicating materials could be useful.

  10. Minimally invasive aortic valve surgery.

    PubMed

    Castrovinci, Sebastiano; Emmanuel, Sam; Moscarelli, Marco; Murana, Giacomo; Caccamo, Giuseppa; Bertolino, Emanuela Clara; Nasso, Giuseppe; Speziale, Giuseppe; Fattouch, Khalil

    2016-09-01

    Aortic valve disease is a prevalent disorder that affects approximately 2% of the general adult population. Surgical aortic valve replacement is the gold standard treatment for symptomatic patients. This treatment has demonstrably proven to be both safe and effective. Over the last few decades, in an attempt to reduce surgical trauma, different minimally invasive approaches for aortic valve replacement have been developed and are now being increasingly utilized. A narrative review of the literature was carried out to describe the surgical techniques for minimally invasive aortic valve surgery and report the results from different experienced centers. Minimally invasive aortic valve replacement is associated with low perioperative morbidity, mortality and a low conversion rate to full sternotomy. Long-term survival appears to be at least comparable to that reported for conventional full sternotomy. Minimally invasive aortic valve surgery, either with a partial upper sternotomy or a right anterior minithoracotomy provides early- and long-term benefits. Given these benefits, it may be considered the standard of care for isolated aortic valve disease. PMID:27582764

  11. A Defense of Semantic Minimalism

    ERIC Educational Resources Information Center

    Kim, Su

    2012-01-01

    Semantic Minimalism is a position about the semantic content of declarative sentences, i.e., the content that is determined entirely by syntax. It is defined by the following two points: "Point 1": The semantic content is a complete/truth-conditional proposition. "Point 2": The semantic content is useful to a theory of…

  12. Minimally invasive aortic valve surgery

    PubMed Central

    Castrovinci, Sebastiano; Emmanuel, Sam; Moscarelli, Marco; Murana, Giacomo; Caccamo, Giuseppa; Bertolino, Emanuela Clara; Nasso, Giuseppe; Speziale, Giuseppe; Fattouch, Khalil

    2016-01-01

    Aortic valve disease is a prevalent disorder that affects approximately 2% of the general adult population. Surgical aortic valve replacement is the gold standard treatment for symptomatic patients. This treatment has demonstrably proven to be both safe and effective. Over the last few decades, in an attempt to reduce surgical trauma, different minimally invasive approaches for aortic valve replacement have been developed and are now being increasingly utilized. A narrative review of the literature was carried out to describe the surgical techniques for minimally invasive aortic valve surgery and report the results from different experienced centers. Minimally invasive aortic valve replacement is associated with low perioperative morbidity, mortality and a low conversion rate to full sternotomy. Long-term survival appears to be at least comparable to that reported for conventional full sternotomy. Minimally invasive aortic valve surgery, either with a partial upper sternotomy or a right anterior minithoracotomy provides early- and long-term benefits. Given these benefits, it may be considered the standard of care for isolated aortic valve disease. PMID:27582764

  13. Minimal formulation of joint motion for biomechanisms

    PubMed Central

    Seth, Ajay; Sherman, Michael; Eastman, Peter; Delp, Scott

    2010-01-01

    Biomechanical systems share many properties with mechanically engineered systems, and researchers have successfully employed mechanical engineering simulation software to investigate the mechanical behavior of diverse biological mechanisms, ranging from biomolecules to human joints. Unlike their man-made counterparts, however, biomechanisms rarely exhibit the simple, uncoupled, pure-axial motion that is engineered into mechanical joints such as sliders, pins, and ball-and-socket joints. Current mechanical modeling software based on internal-coordinate multibody dynamics can formulate engineered joints directly in minimal coordinates, but requires additional coordinates restricted by constraints to model more complex motions. This approach can be inefficient, inaccurate, and difficult for biomechanists to customize. Since complex motion is the rule rather than the exception in biomechanisms, the benefits of minimal coordinate modeling are not fully realized in biomedical research. Here we introduce a practical implementation for empirically-defined internal-coordinate joints, which we call “mobilizers.” A mobilizer encapsulates the observations, measurement frame, and modeling requirements into a hinge specification of the permissible-motion manifold for a minimal set of internal coordinates. Mobilizers support nonlinear mappings that are mathematically equivalent to constraint manifolds but have the advantages of fewer coordinates, no constraints, and exact representation of the biomechanical motion-space—the benefits long enjoyed for internal-coordinate models of mechanical joints. Hinge matrices within the mobilizer are easily specified by user-supplied functions, and provide a direct means of mapping permissible motion derived from empirical data. We present computational results showing substantial performance and accuracy gains for mobilizers versus equivalent joints implemented with constraints. Examples of mobilizers for joints from human biomechanics

  14. Power Minimization techniques for Networked Data Centers.

    SciTech Connect

    Low, Steven; Tang, Kevin

    2011-09-28

    Our objective is to develop a mathematical model to optimize energy consumption at multiple levels in networked data centers, and develop abstract algorithms to optimize not only individual servers, but also coordinate the energy consumption of clusters of servers within a data center and across geographically distributed data centers to minimize the overall energy cost and consumption of brown energy of an enterprise. In this project, we have formulated a variety of optimization models, some stochastic others deterministic, and have obtained a variety of qualitative results on the structural properties, robustness, and scalability of the optimal policies. We have also systematically derived from these models decentralized algorithms to optimize energy efficiency, analyzed their optimality and stability properties. Finally, we have conducted preliminary numerical simulations to illustrate the behavior of these algorithms. We draw the following conclusion. First, there is a substantial opportunity to minimize both the amount and the cost of electricity consumption in a network of datacenters, by exploiting the fact that traffic load, electricity cost, and availability of renewable generation fluctuate over time and across geographical locations. Judiciously matching these stochastic processes can optimize the tradeoff between brown energy consumption, electricity cost, and response time. Second, given the stochastic nature of these three processes, real-time dynamic feedback should form the core of any optimization strategy. The key is to develop decentralized algorithms that can be implemented at different parts of the network as simple, local algorithms that coordinate through asynchronous message passing.

  15. On the generalized minimal massive gravity

    NASA Astrophysics Data System (ADS)

    Setare, M. R.

    2015-09-01

    In this paper we study the Generalized Minimal Massive Gravity (GMMG) in asymptotically AdS3 background. The generalized minimal massive gravity theory is realized by adding the CS deformation term, the higher derivative deformation term, and an extra term to pure Einstein gravity with a negative cosmological constant. We study the linearized excitations around the AdS3 background and find that at special point (tricritical) in parameter space the two massive graviton solutions become massless and they are replaced by two solutions with logarithmic and logarithmic-squared boundary behavior. So it is natural to propose that GMMG model could also provide a holographic description for a 3-rank Logarithmic Conformal Field Theory (LCFT). We calculate the energy of the linearized gravitons in AdS3 background, and show that the theory is free of negative-energy bulk modes. Then we obtain the central charges of the CFT dual explicitly and show GMMG also avoids the aforementioned "bulk-boundary unitarity clash". After that we show that General Zwei-Dreibein Gravity (GZDG) model can reduce to GMMG model. Finally by a Hamiltonian analysis we show that the GMMG model has no Boulware-Deser ghosts and this model propagates only two physical modes.

  16. Minimal Doubling and Point Splitting

    SciTech Connect

    Creutz, M.

    2010-06-14

    Minimally-doubled chiral fermions have the unusual property of a single local field creating two fermionic species. Spreading the field over hypercubes allows construction of combinations that isolate specific modes. Combining these fields into bilinears produces meson fields of specific quantum numbers. Minimally-doubled fermion actions present the possibility of fast simulations while maintaining one exact chiral symmetry. They do, however, introduce some peculiar aspects. An explicit breaking of hyper-cubic symmetry allows additional counter-terms to appear in the renormalization. While a single field creates two different species, spreading this field over nearby sites allows isolation of specific states and the construction of physical meson operators. Finally, lattice artifacts break isospin and give two of the three pseudoscalar mesons an additional contribution to their mass. Depending on the sign of this mass splitting, one can either have a traditional Goldstone pseudoscalar meson or a parity breaking Aoki-like phase.

  17. Anaesthesia for minimally invasive surgery

    PubMed Central

    Dec, Marta

    2015-01-01

    Minimally invasive surgery (MIS) is rising in popularity. It offers well-known benefits to the patient. However, restricted access to the surgical site and gas insufflation into the body cavities may result in severe complications. From the anaesthetic point of view MIS poses unique challenges associated with creation of pneumoperitoneum, carbon dioxide absorption, specific positioning and monitoring a patient to whom the anaesthetist has often restricted access, in a poorly lit environment. Moreover, with refinement of surgical procedures and growing experience the anaesthetist is presented with patients from high-risk groups (obese, elderly, with advanced cardiac and respiratory disease) who once were deemed unsuitable for the laparoscopic technique. Anaesthetic management is aimed at getting the patient safely through the procedure, minimizing the specific risks arising from laparoscopy and the patient's coexisting medical problems, ensuring quick recovery and a relatively pain-free postoperative course with early return to normal function. PMID:26865885

  18. Minimal universal quantum heat machine.

    PubMed

    Gelbwaser-Klimovsky, D; Alicki, R; Kurizki, G

    2013-01-01

    In traditional thermodynamics the Carnot cycle yields the ideal performance bound of heat engines and refrigerators. We propose and analyze a minimal model of a heat machine that can play a similar role in quantum regimes. The minimal model consists of a single two-level system with periodically modulated energy splitting that is permanently, weakly, coupled to two spectrally separated heat baths at different temperatures. The equation of motion allows us to compute the stationary power and heat currents in the machine consistent with the second law of thermodynamics. This dual-purpose machine can act as either an engine or a refrigerator (heat pump) depending on the modulation rate. In both modes of operation, the maximal Carnot efficiency is reached at zero power. We study the conditions for finite-time optimal performance for several variants of the model. Possible realizations of the model are discussed. PMID:23410316

  19. Principle of minimal work fluctuations.

    PubMed

    Xiao, Gaoyang; Gong, Jiangbin

    2015-08-01

    Understanding and manipulating work fluctuations in microscale and nanoscale systems are of both fundamental and practical interest. For example, in considering the Jarzynski equality 〈e-βW〉=e-βΔF, a change in the fluctuations of e-βW may impact how rapidly the statistical average of e-βW converges towards the theoretical value e-βΔF, where W is the work, β is the inverse temperature, and ΔF is the free energy difference between two equilibrium states. Motivated by our previous study aiming at the suppression of work fluctuations, here we obtain a principle of minimal work fluctuations. In brief, adiabatic processes as treated in quantum and classical adiabatic theorems yield the minimal fluctuations in e-βW. In the quantum domain, if a system initially prepared at thermal equilibrium is subjected to a work protocol but isolated from a bath during the time evolution, then a quantum adiabatic process without energy level crossing (or an assisted adiabatic process reaching the same final states as in a conventional adiabatic process) yields the minimal fluctuations in e-βW, where W is the quantum work defined by two energy measurements at the beginning and at the end of the process. In the classical domain where the classical work protocol is realizable by an adiabatic process, then the classical adiabatic process also yields the minimal fluctuations in e-βW. Numerical experiments based on a Landau-Zener process confirm our theory in the quantum domain, and our theory in the classical domain explains our previous numerical findings regarding the suppression of classical work fluctuations [G. Y. Xiao and J. B. Gong, Phys. Rev. E 90, 052132 (2014)]. PMID:26382367

  20. Principle of minimal work fluctuations

    NASA Astrophysics Data System (ADS)

    Xiao, Gaoyang; Gong, Jiangbin

    2015-08-01

    Understanding and manipulating work fluctuations in microscale and nanoscale systems are of both fundamental and practical interest. For example, in considering the Jarzynski equality =e-β Δ F , a change in the fluctuations of e-β W may impact how rapidly the statistical average of e-β W converges towards the theoretical value e-β Δ F, where W is the work, β is the inverse temperature, and Δ F is the free energy difference between two equilibrium states. Motivated by our previous study aiming at the suppression of work fluctuations, here we obtain a principle of minimal work fluctuations. In brief, adiabatic processes as treated in quantum and classical adiabatic theorems yield the minimal fluctuations in e-β W. In the quantum domain, if a system initially prepared at thermal equilibrium is subjected to a work protocol but isolated from a bath during the time evolution, then a quantum adiabatic process without energy level crossing (or an assisted adiabatic process reaching the same final states as in a conventional adiabatic process) yields the minimal fluctuations in e-β W, where W is the quantum work defined by two energy measurements at the beginning and at the end of the process. In the classical domain where the classical work protocol is realizable by an adiabatic process, then the classical adiabatic process also yields the minimal fluctuations in e-β W. Numerical experiments based on a Landau-Zener process confirm our theory in the quantum domain, and our theory in the classical domain explains our previous numerical findings regarding the suppression of classical work fluctuations [G. Y. Xiao and J. B. Gong, Phys. Rev. E 90, 052132 (2014), 10.1103/PhysRevE.90.052132].

  1. Modeling Human Behavior to Anticipate Insider Attacks

    SciTech Connect

    Greitzer, Frank L.; Hohimer, Ryan E.

    2011-06-09

    The insider threat ranks among the most pressing cybersecurity challenges that threaten government and industry information infrastructures. To date, no systematic methods have been developed that provide a complete and effective approach to prevent data leakage, espionage and sabotage. Current practice is forensic in nature, relegating to the analyst the bulk of the responsibility to monitor, analyze, and correlate an overwhelming amount of data. We describe a predictive modeling framework that integrates a diverse set of data sources from the cyber domain as well as inferred psychological/motivational factors that may underlie malicious insider exploits. This comprehensive threat assessment approach provides automated support for the detection of high-risk behavioral “triggers” to help focus the analyst’s attention and inform the analysis. Designed to be domain independent, the system may be applied to many different threat and warning analysis/sensemaking problems.

  2. Minimizing medical litigation, part 2.

    PubMed

    Harold, Tan Keng Boon

    2006-01-01

    Provider-patient disputes are inevitable in the healthcare sector. Healthcare providers and regulators should recognize this and plan opportunities to enforce alternative dispute resolution (ADR) a early as possible in the care delivery process. Negotiation is often the main dispute resolution method used by local healthcare providers, failing which litigation would usually follow. The role of mediation in resolving malpractice disputes has been minimal. Healthcare providers, administrators, and regulators should therefore look toward a post-event communication-cum-mediation framework as the key national strategy to resolving malpractice disputes. PMID:16711089

  3. The minimal scenario of leptogenesis

    NASA Astrophysics Data System (ADS)

    Blanchet, Steve; Di Bari, Pasquale

    2012-12-01

    We review the main features and results of thermal leptogenesis within the type I seesaw mechanism, the minimal extension of the Standard Model explaining neutrino masses and mixing. After presenting the simplest approach, the vanilla scenario, we discuss various important developments of recent years, such as the inclusion of lepton and heavy neutrino flavour effects, a description beyond a hierarchical heavy neutrino mass spectrum and an improved kinetic description within the density matrix and the closed-time-path formalisms. We also discuss how leptogenesis can ultimately represent an important phenomenological tool to test the seesaw mechanism and the underlying model of new physics.

  4. About the ZOOM minimization package

    SciTech Connect

    Fischler, M.; Sachs, D.; /Fermilab

    2004-11-01

    A new object-oriented Minimization package is available for distribution in the same manner as CLHEP. This package, designed for use in HEP applications, has all the capabilities of Minuit, but is a re-write from scratch, adhering to modern C++ design principles. A primary goal of this package is extensibility in several directions, so that its capabilities can be kept fresh with as little maintenance effort as possible. This package is distinguished by the priority that was assigned to C++ design issues, and the focus on producing an extensible system that will resist becoming obsolete.

  5. Prepulse minimization in KALI-5000.

    PubMed

    Kumar, D Durga Praveen; Mitra, S; Senthil, K; Sharma, Vishnu K; Singh, S K; Roy, A; Sharma, Archana; Nagesh, K V; Chakravarthy, D P

    2009-07-01

    A pulse power system (1 MV, 50 kA, and 100 ns) based on Marx generator and Blumlein pulse forming line has been built for generating high power microwaves. The Blumlein configuration poses a prepulse problem and hence the diode gap had to be increased to match the diode impedance to the Blumlein impedance during the main pulse. A simple method to eliminate prepulse voltage using a vacuum sparkgap and a resistor is given. Another fundamental approach of increasing the inductance of Marx generator to minimize the prepulse voltage is also presented. Experimental results for both of these configurations are given. PMID:19655979

  6. Prepulse minimization in KALI-5000

    NASA Astrophysics Data System (ADS)

    Kumar, D. Durga Praveen; Mitra, S.; Senthil, K.; Sharma, Vishnu K.; Singh, S. K.; Roy, A.; Sharma, Archana; Nagesh, K. V.; Chakravarthy, D. P.

    2009-07-01

    A pulse power system (1 MV, 50 kA, and 100 ns) based on Marx generator and Blumlein pulse forming line has been built for generating high power microwaves. The Blumlein configuration poses a prepulse problem and hence the diode gap had to be increased to match the diode impedance to the Blumlein impedance during the main pulse. A simple method to eliminate prepulse voltage using a vacuum sparkgap and a resistor is given. Another fundamental approach of increasing the inductance of Marx generator to minimize the prepulse voltage is also presented. Experimental results for both of these configurations are given.

  7. Risk minimization through portfolio replication

    NASA Astrophysics Data System (ADS)

    Ciliberti, S.; Mã©Zard, M.

    2007-05-01

    We use a replica approach to deal with portfolio optimization problems. A given risk measure is minimized using empirical estimates of asset values correlations. We study the phase transition which happens when the time series is too short with respect to the size of the portfolio. We also study the noise sensitivity of portfolio allocation when this transition is approached. We consider explicitely the cases where the absolute deviation and the conditional value-at-risk are chosen as a risk measure. We show how the replica method can study a wide range of risk measures, and deal with various types of time series correlations, including realistic ones with volatility clustering.

  8. Diagnosis of minimal hepatic encephalopathy.

    PubMed

    Weissenborn, Karin

    2015-03-01

    Minimal hepatic encephalopathy (mHE) has significant impact upon a liver patient's daily living and health related quality of life. Therefore a majority of clinicians agree that mHE should be diagnosed and treated. The optimal means for diagnosing mHE, however, is controversial. This paper describes the currently most frequently used methods-EEG, critical flicker frequency, Continuous Reaction time Test, Inhibitory Control Test, computerized test batteries such as the Cognitive Drug Research test battery, the psychometric hepatic encephalopathy score (PHES) and the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS)-and their pros and cons. PMID:26041959

  9. Detecting and classifying method based on similarity matching of Android malware behavior with profile.

    PubMed

    Jang, Jae-Wook; Yun, Jaesung; Mohaisen, Aziz; Woo, Jiyoung; Kim, Huy Kang

    2016-01-01

    Mass-market mobile security threats have increased recently due to the growth of mobile technologies and the popularity of mobile devices. Accordingly, techniques have been introduced for identifying, classifying, and defending against mobile threats utilizing static, dynamic, on-device, and off-device techniques. Static techniques are easy to evade, while dynamic techniques are expensive. On-device techniques are evasion, while off-device techniques need being always online. To address some of those shortcomings, we introduce Andro-profiler, a hybrid behavior based analysis and classification system for mobile malware. Andro-profiler main goals are efficiency, scalability, and accuracy. For that, Andro-profiler classifies malware by exploiting the behavior profiling extracted from the integrated system logs including system calls. Andro-profiler executes a malicious application on an emulator in order to generate the integrated system logs, and creates human-readable behavior profiles by analyzing the integrated system logs. By comparing the behavior profile of malicious application with representative behavior profile for each malware family using a weighted similarity matching technique, Andro-profiler detects and classifies it into malware families. The experiment results demonstrate that Andro-profiler is scalable, performs well in detecting and classifying malware with accuracy greater than 98 %, outperforms the existing state-of-the-art work, and is capable of identifying 0-day mobile malware samples. PMID:27006882

  10. Finding minimal action sequences with a simple evaluation of actions

    PubMed Central

    Shah, Ashvin; Gurney, Kevin N.

    2014-01-01

    Animals are able to discover the minimal number of actions that achieves an outcome (the minimal action sequence). In most accounts of this, actions are associated with a measure of behavior that is higher for actions that lead to the outcome with a shorter action sequence, and learning mechanisms find the actions associated with the highest measure. In this sense, previous accounts focus on more than the simple binary signal of “was the outcome achieved?”; they focus on “how well was the outcome achieved?” However, such mechanisms may not govern all types of behavioral development. In particular, in the process of action discovery (Redgrave and Gurney, 2006), actions are reinforced if they simply lead to a salient outcome because biological reinforcement signals occur too quickly to evaluate the consequences of an action beyond an indication of the outcome's occurrence. Thus, action discovery mechanisms focus on the simple evaluation of “was the outcome achieved?” and not “how well was the outcome achieved?” Notwithstanding this impoverishment of information, can the process of action discovery find the minimal action sequence? We address this question by implementing computational mechanisms, referred to in this paper as no-cost learning rules, in which each action that leads to the outcome is associated with the same measure of behavior. No-cost rules focus on “was the outcome achieved?” and are consistent with action discovery. No-cost rules discover the minimal action sequence in simulated tasks and execute it for a substantial amount of time. Extensive training, however, results in extraneous actions, suggesting that a separate process (which has been proposed in action discovery) must attenuate learning if no-cost rules participate in behavioral development. We describe how no-cost rules develop behavior, what happens when attenuation is disrupted, and relate the new mechanisms to wider computational and biological context. PMID:25506326

  11. Microrover Operates With Minimal Computation

    NASA Technical Reports Server (NTRS)

    Miller, David P.; Loch, John L.; Gat, Erann; Desai, Rajiv S.; Angle, Colin; Bickler, Donald B.

    1992-01-01

    Small, light, highly mobile robotic vehicles called "microrovers" use sensors and artificial intelligence to perform complicated tasks autonomously. Vehicle navigates, avoids obstacles, and picks up objects using reactive control scheme selected from among few preprogrammed behaviors to respond to environment while executing assigned task. Under development for exploration and mining of other planets. Also useful in firefighting, cleaning up chemical spills, and delivering materials in factories. Reactive control scheme and principle of behavior-description language useful in reducing computational loads in prosthetic limbs and automotive collision-avoidance systems.

  12. Minimizing travel claims cost with minimal-spanning tree model

    NASA Astrophysics Data System (ADS)

    Jamalluddin, Mohd Helmi; Jaafar, Mohd Azrul; Amran, Mohd Iskandar; Ainul, Mohd Sharizal; Hamid, Aqmar; Mansor, Zafirah Mohd; Nopiah, Zulkifli Mohd

    2014-06-01

    Travel demand necessitates a big expenditure in spending, as has been proven by the National Audit Department (NAD). Every year the auditing process is carried out throughout the country involving official travel claims. This study focuses on the use of the Spanning Tree model to determine the shortest path to minimize the cost of the NAD's official travel claims. The objective is to study the possibility of running a network based in the Kluang District Health Office to eight Rural Clinics in Johor state using the Spanning Tree model applications for optimizing travelling distances and make recommendations to the senior management of the Audit Department to analyze travelling details before an audit is conducted. Result of this study reveals that there were claims of savings of up to 47.4% of the original claims, over the course of the travel distance.

  13. Annual Waste Minimization Summary Report

    SciTech Connect

    Alfred J. Karns

    2007-01-01

    This report summarizes the waste minimization efforts undertaken by National Security Technologies, LLC (NSTec), for the U. S. Department of Energy (DOE) National Nuclear Security Administration Nevada Site Office (NNSA/NSO), during CY06. This report was developed in accordance with the requirements of the Nevada Test Site (NTS) Resource Conservation and Recovery Act (RCRA) Permit (No. NEV HW0021) and as clarified in a letter dated April 21, 1995, from Paul Liebendorfer of the Nevada Division of Environmental Protection to Donald Elle of the DOE, Nevada Operations Office. The NNSA/NSO Pollution Prevention (P2) Program establishes a process to reduce the volume and toxicity of waste generated by the NNSA/NSO and ensures that proposed methods of treatment, storage, and/or disposal of waste minimize potential threats to human health and the environment. The following information provides an overview of the P2 Program, major P2 accomplishments during the reporting year, a comparison of the current year waste generation to prior years, and a description of efforts undertaken during the year to reduce the volume and toxicity of waste generated by the NNSA/NSO.

  14. Less minimal supersymmetric standard model

    SciTech Connect

    de Gouvea, Andre; Friedland, Alexander; Murayama, Hitoshi

    1998-03-28

    Most of the phenomenological studies of supersymmetry have been carried out using the so-called minimal supergravity scenario, where one assumes a universal scalar mass, gaugino mass, and trilinear coupling at M{sub GUT}. Even though this is a useful simplifying assumption for phenomenological analyses, it is rather too restrictive to accommodate a large variety of phenomenological possibilities. It predicts, among other things, that the lightest supersymmetric particle (LSP) is an almost pure B-ino, and that the {mu}-parameter is larger than the masses of the SU(2){sub L} and U(1){sub Y} gauginos. We extend the minimal supergravity framework by introducing one extra parameter: the Fayet'Iliopoulos D-term for the hypercharge U(1), D{sub Y}. Allowing for this extra parameter, we find a much more diverse phenomenology, where the LSP is {tilde {nu}}{sub {tau}}, {tilde {tau}} or a neutralino with a large higgsino content. We discuss the relevance of the different possibilities to collider signatures. The same type of extension can be done to models with the gauge mediation of supersymmetry breaking. We argue that it is not wise to impose cosmological constraints on the parameter space.

  15. Symmetry breaking for drag minimization

    NASA Astrophysics Data System (ADS)

    Roper, Marcus; Squires, Todd M.; Brenner, Michael P.

    2005-11-01

    For locomotion at high Reynolds numbers drag minimization favors fore-aft asymmetric slender shapes with blunt noses and sharp trailing edges. On the other hand, in an inertialess fluid the drag experienced by a body is independent of whether it travels forward or backward through the fluid, so there is no advantage to having a single preferred swimming direction. In fact numerically determined minimum drag shapes are known to exhibit almost no fore-aft asymmetry even at moderate Re. We show that asymmetry persists, albeit extremely weakly, down to vanishingly small Re, scaling asymptotically as Re^3. The need to minimize drag to maximize speed for a given propulsive capacity gives one possible mechanism for the increasing asymmetry in the body plans seen in nature, as organisms increase in size and swimming speed from bacteria like E-Coli up to pursuit predator fish such as tuna. If it is the dominant mechanism, then this signature scaling will be observed in the shapes of motile micro-organisms.

  16. Next-to-minimal SOFTSUSY

    NASA Astrophysics Data System (ADS)

    Allanach, B. C.; Athron, P.; Tunstall, Lewis C.; Voigt, A.; Williams, A. G.

    2014-09-01

    We describe an extension to the SOFTSUSY program that provides for the calculation of the sparticle spectrum in the Next-to-Minimal Supersymmetric Standard Model (NMSSM), where a chiral superfield that is a singlet of the Standard Model gauge group is added to the Minimal Supersymmetric Standard Model (MSSM) fields. Often, a Z3 symmetry is imposed upon the model. SOFTSUSY can calculate the spectrum in this case as well as the case where general Z3 violating (denoted as =) terms are added to the soft supersymmetry breaking terms and the superpotential. The user provides a theoretical boundary condition for the couplings and mass terms of the singlet. Radiative electroweak symmetry breaking data along with electroweak and CKM matrix data are used as weak-scale boundary conditions. The renormalisation group equations are solved numerically between the weak scale and a high energy scale using a nested iterative algorithm. This paper serves as a manual to the NMSSM mode of the program, detailing the approximations and conventions used. Catalogue identifier: ADPM_v4_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADPM_v4_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 154886 No. of bytes in distributed program, including test data, etc.: 1870890 Distribution format: tar.gz Programming language: C++, fortran. Computer: Personal computer. Operating system: Tested on Linux 3.x. Word size: 64 bits Classification: 11.1, 11.6. Does the new version supersede the previous version?: Yes Catalogue identifier of previous version: ADPM_v3_0 Journal reference of previous version: Comput. Phys. Comm. 183 (2012) 785 Nature of problem: Calculating supersymmetric particle spectrum and mixing parameters in the next-to-minimal supersymmetric standard model. The solution to the

  17. Update on designing and building minimal cells

    PubMed Central

    Jewett, Michael C.; Forster, Anthony C.

    2010-01-01

    Summary Minimal cells comprise only the genes and biomolecular machinery necessary for basic life. Synthesizing minimal and minimized cells will improve understanding of core biology, enhance development of biotechnology strains of bacteria, and enable evolutionary optimization of natural and unnatural biopolymers. Design and construction of minimal cells is proceeding in two different directions: “top-down” reduction of bacterial genomes in vivo and “bottom-up” integration of DNA/RNA/protein/membrane syntheses in vitro. Major progress in the last 5 years has occurred in synthetic genomics, minimization of the Escherichia coli genome, sequencing of minimal bacterial endosymbionts, identification of essential genes, and integration of biochemical systems. PMID:20638265

  18. Simulating granular materials by energy minimization

    NASA Astrophysics Data System (ADS)

    Krijgsman, D.; Luding, S.

    2016-03-01

    Discrete element methods are extremely helpful in understanding the complex behaviors of granular media, as they give valuable insight into all internal variables of the system. In this paper, a novel discrete element method for performing simulations of granular media is presented, based on the minimization of the potential energy in the system. Contrary to most discrete element methods (i.e., soft-particle method, event-driven method, and non-smooth contact dynamics), the system does not evolve by (approximately) integrating Newtons equations of motion in time, but rather by searching for mechanical equilibrium solutions for the positions of all particles in the system, which is mathematically equivalent to locally minimizing the potential energy. The new method allows for the rapid creation of jammed initial conditions (to be used for further studies) and for the simulation of quasi-static deformation problems. The major advantage of the new method is that it allows for truly static deformations. The system does not evolve with time, but rather with the externally applied strain or load, so that there is no kinetic energy in the system, in contrast to other quasi-static methods. The performance of the algorithm for both types of applications of the method is tested. Therefore we look at the required number of iterations, for the system to converge to a stable solution. For each single iteration, the required computational effort scales linearly with the number of particles. During the process of creating initial conditions, the required number of iterations for two-dimensional systems scales with the square root of the number of particles in the system. The required number of iterations increases for systems closer to the jamming packing fraction. For a quasi-static pure shear deformation simulation, the results of the new method are validated by regular soft-particle dynamics simulations. The energy minimization algorithm is able to capture the evolution of the

  19. Minimally invasive posterior hamstring harvest.

    PubMed

    Wilson, Trent J; Lubowitz, James H

    2013-01-01

    Autogenous hamstring harvesting for knee ligament reconstruction is a well-established standard. Minimally invasive posterior hamstring harvest is a simple, efficient, reproducible technique for harvest of the semitendinosus or gracilis tendon or both medial hamstring tendons. A 2- to 3-cm longitudinal incision from the popliteal crease proximally, in line with the semitendinosus tendon, is sufficient. The deep fascia is bluntly penetrated, and the tendon or tendons are identified. Adhesions are dissected. Then, an open tendon stripper is used to release the tendon or tendons proximally; a closed, sharp tendon stripper is used to release the tendon or tendons from the pes. Layered, absorbable skin closure is performed, and the skin is covered with a skin sealant, bolster dressing, and plastic adhesive bandage for 2 weeks. PMID:24266003

  20. Minimally Invasive Spigelian Hernia Repair

    PubMed Central

    Baucom, Catherine; Nguyen, Quan D.; Hidalgo, Marco

    2009-01-01

    Introduction: Spigelian hernia is an uncommon ventral hernia characterized by a defect in the linea semilunaris. Repair of spigelian hernia has traditionally been accomplished via an open transverse incision and primary repair. The purpose of this article is to present 2 case reports of incarcerated spigelian hernia that were successfully repaired laparoscopically using Gortex mesh and to present a review of the literature regarding laparoscopic repair of spigelian hernias. Methods: Retrospective chart review and Medline literature search. Results: Two patients underwent laparoscopic mesh repair of incarcerated spigelian hernias. Both were started on a regular diet on postoperative day 1 and discharged on postoperative days 2 and 3. One patient developed a seroma that resolved without intervention. There was complete resolution of preoperative symptoms at the 12-month follow-up. Conclusion: Minimally invasive repair of spigelian hernias is an alternative to the traditional open surgical technique. Further studies are needed to directly compare the open and the laparoscopic repair. PMID:19660230

  1. Minimally invasive radioguided parathyroidectomy (MIRP).

    PubMed

    Goldstein, R E; Martin, W H; Richards, K

    2003-06-01

    The technique of parathyroidectomy has traditionally involved a bilateral exploration of the neck with the intent of visualizing 4 parathyroid glands and resecting pathologically enlarged glands. Parathyroid scanning using technetium-99m sestamibi has evolved and can now localize 80% to 90% of parathyroid adenomas. The technique of minimally invasive radioguided parathyroidectomy (MIRP) is a surgical option for most patients with primary hyperparathyroidism and a positive preoperative parathyroid scan. The technique makes use of a hand-held gamma probe that is used intraoperatively to guide the dissection in a highly directed manner with the procedure often performed under local anesthesia. The technique results in excellent cure rates while allowing most patients to leave the hospital within a few hours after the completion of the procedure. Current data also suggest the procedure can decrease hospital charges by approximately 50%. This technique may significantly change the management of primary hyperparathyroidism. PMID:12955045

  2. [MINIMALLY INVASIVE AORTIC VALVE REPLACEMENT].

    PubMed

    Tabata, Minoru

    2016-03-01

    Minimally invasive aortic valve replacement (MIAVR) is defined as aortic valve replacement avoiding full sternotomy. Common approaches include a partial sternotomy right thoracotomy, and a parasternal approach. MIAVR has been shown to have advantages over conventional AVR such as shorter length of stay and smaller amount of blood transfusion and better cosmesis. However, it is also known to have disadvantages such as longer cardiopulmonary bypass and aortic cross-clamp times and potential complications related to peripheral cannulation. Appropriate patient selection is very important. Since the procedure is more complex than conventional AVR, more intensive teamwork in the operating room is essential. Additionally, a team approach during postoperative management is critical to maximize the benefits of MIAVR. PMID:27295772

  3. Strategies to Minimize Antibiotic Resistance

    PubMed Central

    Lee, Chang-Ro; Cho, Ill Hwan; Jeong, Byeong Chul; Lee, Sang Hee

    2013-01-01

    Antibiotic resistance can be reduced by using antibiotics prudently based on guidelines of antimicrobial stewardship programs (ASPs) and various data such as pharmacokinetic (PK) and pharmacodynamic (PD) properties of antibiotics, diagnostic testing, antimicrobial susceptibility testing (AST), clinical response, and effects on the microbiota, as well as by new antibiotic developments. The controlled use of antibiotics in food animals is another cornerstone among efforts to reduce antibiotic resistance. All major resistance-control strategies recommend education for patients, children (e.g., through schools and day care), the public, and relevant healthcare professionals (e.g., primary-care physicians, pharmacists, and medical students) regarding unique features of bacterial infections and antibiotics, prudent antibiotic prescribing as a positive construct, and personal hygiene (e.g., handwashing). The problem of antibiotic resistance can be minimized only by concerted efforts of all members of society for ensuring the continued efficiency of antibiotics. PMID:24036486

  4. Minimizing the pain on burnout

    SciTech Connect

    Billings, A.

    1985-03-01

    An investment in an oil and gas shelter warrants an additional investment to fund tax liability on burnout. A relatively liquid and low-risk investment is preferable so as to assure timely satisfaction of tax liability when burnout occurs. If an investor decides to allow the shelter to die a timely death, the investment funds could be used to fund annual tax liability. In situations where a leak develops, the fund will once again be invaluable. When a leak or burnout occurs, investors may be able to do no more than minimize their maximum losses. Relief of debt on most dispositions will be deemed receipt of cash, thus triggering gains. Ordinary income will result by operation of Code Sections 1245, 1250, and 1254. Bankruptcy or a charitable contribution will grant limited reprieve from tax losses; however, economic losses will still result.

  5. Minimal unitary (covariant) scattering theory

    SciTech Connect

    Lindesay, J.V.; Markevich, A.

    1983-06-01

    In the minimal three particle equations developed by Lindesay the two body input amplitude was an on shell relativistic generalization of the non-relativistic scattering model characterized by a single mass parameter ..mu.. which in the two body (m + m) system looks like an s-channel bound state (..mu.. < 2m) or virtual state (..mu.. > 2m). Using this driving term in covariant Faddeev equations generates a rich covariant and unitary three particle dynamics. However, the simplest way of writing the relativisitic generalization of the Faddeev equations can take the on shell Mandelstam parameter s = 4(q/sup 2/ + m/sup 2/), in terms of which the two particle input is expressed, to negative values in the range of integration required by the dynamics. This problem was met in the original treatment by multiplying the two particle input amplitude by THETA(s). This paper provides what we hope to be a more direct way of meeting the problem.

  6. Minimally packed phases in holography

    NASA Astrophysics Data System (ADS)

    Donos, Aristomenis; Gauntlett, Jerome P.

    2016-03-01

    We numerically construct asymptotically AdS black brane solutions of D = 4 Einstein-Maxwell theory coupled to a pseudoscalar. The solutions are holographically dual to d = 3 CFTs at finite chemical potential and in a constant magnetic field, which spontaneously break translation invariance leading to the spontaneous formation of abelian and momentum magnetisation currents flowing around the plaquettes of a periodic Bravais lattice. We analyse the three-dimensional moduli space of lattice solutions, which are generically oblique, and show, for a specific value of the magnetic field, that the free energy is minimised by the triangular lattice, associated with minimal packing of circles in the plane. We show that the average stress tensor for the thermodynamically preferred phase is that of a perfect fluid and that this result applies more generally to spontaneously generated periodic phases. The triangular structure persists at low temperatures indicating the existence of novel crystalline ground states.

  7. The minimal composite Higgs model

    NASA Astrophysics Data System (ADS)

    Agashe, Kaustubh; Contino, Roberto; Pomarol, Alex

    2005-07-01

    We study the idea of a composite Higgs in the framework of a five-dimensional AdS theory. We present the minimal model of the Higgs as a pseudo-Goldstone boson in which electroweak symmetry is broken dynamically via top loop effects, all flavour problems are solved, and contributions to electroweak precision observables are below experimental bounds. Since the 5D theory is weakly coupled, we are able to fully determine the Higgs potential and other physical quantities. The lightest resonances are expected to have a mass around 2 TeV and should be discovered at the LHC. The top sector is mostly composite and deviations from Standard Model couplings are expected.

  8. Natural supersymmetric minimal dark matter

    NASA Astrophysics Data System (ADS)

    Fabbrichesi, Marco; Urbano, Alfredo

    2016-03-01

    We show how the Higgs boson mass is protected from the potentially large corrections due to the introduction of minimal dark matter if the new physics sector is made supersymmetric. The fermionic dark matter candidate (a 5-plet of S U (2 )L) is accompanied by a scalar state. The weak gauge sector is made supersymmetric, and the Higgs boson is embedded in a supersymmetric multiplet. The remaining standard model states are nonsupersymmetric. Nonvanishing corrections to the Higgs boson mass only appear at three-loop level, and the model is natural for dark matter masses up to 15 TeV—a value larger than the one required by the cosmological relic density. The construction presented stands as an example of a general approach to naturalness that solves the little hierarchy problem which arises when new physics is added beyond the standard model at an energy scale around 10 TeV.

  9. Chemical basis for minimal cognition.

    PubMed

    Hanczyc, Martin M; Ikegami, Takashi

    2010-01-01

    We have developed a simple chemical system capable of self-movement in order to study the physicochemical origins of movement. We propose how this system may be useful in the study of minimal perception and cognition. The system consists simply of an oil droplet in an aqueous environment. A chemical reaction within the oil droplet induces an instability, the symmetry of the oil droplet breaks, and the droplet begins to move through the aqueous phase. The complement of physical phenomena that is then generated indicates the presence of feedback cycles that, as will be argued, form the basis for self-regulation, homeostasis, and perhaps an extended form of autopoiesis. We discuss the result that simple chemical systems are capable of sensory-motor coupling and possess a homeodynamic state from which cognitive processes may emerge. PMID:20586578

  10. A minimal little Higgs model

    NASA Astrophysics Data System (ADS)

    Barceló, Roberto; Masip, Manuel

    2008-11-01

    We discuss a little Higgs scenario that introduces below the TeV scale just the two minimal ingredients of these models, a vectorlike T quark and a singlet component (implying anomalous couplings) in the Higgs field, together with a pseudoscalar singlet η. In the model, which is a variation of Schmaltz’s simplest little Higgs model, all the extra vector bosons are much heavier than the T quark. In the Yukawa sector the global symmetry is approximate, implying a single large coupling per flavor, whereas in the scalar sector it is only broken at the loop level. We obtain the one-loop effective potential and show that it provides acceptable masses for the Higgs h and for the singlet η with no need for an extra μ term. We find that mη can be larger than mh/2, which would forbid the (otherwise dominant) decay mode h→ηη.

  11. Waste minimization in analytical methods

    SciTech Connect

    Green, D.W.; Smith, L.L.; Crain, J.S.; Boparai, A.S.; Kiely, J.T.; Yaeger, J.S. Schilling, J.B.

    1995-05-01

    The US Department of Energy (DOE) will require a large number of waste characterizations over a multi-year period to accomplish the Department`s goals in environmental restoration and waste management. Estimates vary, but two million analyses annually are expected. The waste generated by the analytical procedures used for characterizations is a significant source of new DOE waste. Success in reducing the volume of secondary waste and the costs of handling this waste would significantly decrease the overall cost of this DOE program. Selection of appropriate analytical methods depends on the intended use of the resultant data. It is not always necessary to use a high-powered analytical method, typically at higher cost, to obtain data needed to make decisions about waste management. Indeed, for samples taken from some heterogeneous systems, the meaning of high accuracy becomes clouded if the data generated are intended to measure a property of this system. Among the factors to be considered in selecting the analytical method are the lower limit of detection, accuracy, turnaround time, cost, reproducibility (precision), interferences, and simplicity. Occasionally, there must be tradeoffs among these factors to achieve the multiple goals of a characterization program. The purpose of the work described here is to add waste minimization to the list of characteristics to be considered. In this paper the authors present results of modifying analytical methods for waste characterization to reduce both the cost of analysis and volume of secondary wastes. Although tradeoffs may be required to minimize waste while still generating data of acceptable quality for the decision-making process, they have data demonstrating that wastes can be reduced in some cases without sacrificing accuracy or precision.

  12. Minimalism context-aware displays.

    PubMed

    Cai, Yang

    2004-12-01

    Despite the rapid development of cyber technologies, today we still have very limited attention and communication bandwidth to process the increasing information flow. The goal of the study is to develop a context-aware filter to match the information load with particular needs and capacities. The functions include bandwidth-resolution trade-off and user context modeling. From the empirical lab studies, it is found that the resolution of images can be reduced in order of magnitude if the viewer knows that he/she is looking for particular features. The adaptive display queue is optimized with real-time operational conditions and user's inquiry history. Instead of measuring operator's behavior directly, ubiquitous computing models are developed to anticipate user's behavior from the operational environment data. A case study of the video stream monitoring for transit security is discussed in the paper. In addition, the author addresses the future direction of coherent human-machine vision systems. PMID:15687797

  13. The Impact of Emotions and Empathy-Related Traits on Punishment Behavior: Introduction and Validation of the Inequality Game.

    PubMed

    Klimecki, Olga M; Vuilleumier, Patrik; Sander, David

    2016-01-01

    In the prevention and resolution of conflicts in social contexts, an important step is to understand how different emotions and empathic traits are linked to punishment behaviors. Unfortunately, few paradigms exist to study these phenomena. Here, we developed the Inequality Game (IG) as an economic and verbal interaction paradigm in which participants are faced with an "unfair other" as opposed to a "fair other" and subsequently have the opportunity to engage in a range of social behaviors. These social behaviors include cooperative or competitive economic choices and nice or derogatory verbal behavior toward the unfair and fair other. Participants could thus engage in punishment or forgiveness behavior toward the unfair other as well as in cooperative or aggressive behavior toward the fair other. We validated the IG through multimodal measures comprising the assessment of personality traits, emotions (by means of facial expressions and self-reports), arousal (by means of skin conductance responses), physical effort (force exertion), and behavioral reactions. Second, we examined the influence of emotions and empathy-related traits on punishment behavior. With regard to emotions, we observed a positive relation between malicious joy and punishment behavior. This result highlights the role of reward-related mechanisms in favoring punishment behavior. In addition, different empathic traits had opposing effects on antisocial behavior. Whereas personal distress predicted aggressive verbal behavior, perspective taking and empathic concern predicted a reduction in punishment behavior. Empathic traits also modulated emotional experience and person evaluations, such that perspective taking was related to more positive affect (less frowning and more smiling) and a more favorable evaluation of the unfair other. The current data validate the IG, reveal that malicious joy is positively related to punishment behavior, and show that different types of empathic traits can have

  14. The Impact of Emotions and Empathy-Related Traits on Punishment Behavior: Introduction and Validation of the Inequality Game

    PubMed Central

    Klimecki, Olga M.; Vuilleumier, Patrik; Sander, David

    2016-01-01

    In the prevention and resolution of conflicts in social contexts, an important step is to understand how different emotions and empathic traits are linked to punishment behaviors. Unfortunately, few paradigms exist to study these phenomena. Here, we developed the Inequality Game (IG) as an economic and verbal interaction paradigm in which participants are faced with an “unfair other” as opposed to a “fair other” and subsequently have the opportunity to engage in a range of social behaviors. These social behaviors include cooperative or competitive economic choices and nice or derogatory verbal behavior toward the unfair and fair other. Participants could thus engage in punishment or forgiveness behavior toward the unfair other as well as in cooperative or aggressive behavior toward the fair other. We validated the IG through multimodal measures comprising the assessment of personality traits, emotions (by means of facial expressions and self-reports), arousal (by means of skin conductance responses), physical effort (force exertion), and behavioral reactions. Second, we examined the influence of emotions and empathy-related traits on punishment behavior. With regard to emotions, we observed a positive relation between malicious joy and punishment behavior. This result highlights the role of reward-related mechanisms in favoring punishment behavior. In addition, different empathic traits had opposing effects on antisocial behavior. Whereas personal distress predicted aggressive verbal behavior, perspective taking and empathic concern predicted a reduction in punishment behavior. Empathic traits also modulated emotional experience and person evaluations, such that perspective taking was related to more positive affect (less frowning and more smiling) and a more favorable evaluation of the unfair other. The current data validate the IG, reveal that malicious joy is positively related to punishment behavior, and show that different types of empathic traits can

  15. Minimal length uncertainty and accelerating universe

    NASA Astrophysics Data System (ADS)

    Farmany, A.; Mortazavi, S. S.

    2016-06-01

    In this paper, minimal length uncertainty is used as a constraint to solve the Friedman equation. It is shown that, based on the minimal length uncertainty principle, the Hubble scale is decreasing which corresponds to an accelerating universe.

  16. Mini-Med School Planning Guide

    ERIC Educational Resources Information Center

    National Institutes of Health, Office of Science Education, 2008

    2008-01-01

    Mini-Med Schools are public education programs now offered by more than 70 medical schools, universities, research institutions, and hospitals across the nation. There are even Mini-Med Schools in Ireland, Malta, and Canada! The program is typically a lecture series that meets once a week and provides "mini-med students" information on some of the…

  17. Closed locally minimal nets on tetrahedra

    SciTech Connect

    Strelkova, Nataliya P

    2011-01-31

    Closed locally minimal networks are in a sense a generalization of closed geodesics. A complete classification is known of closed locally minimal networks on regular (and generally any equihedral) tetrahedra. In the present paper certain necessary and certain sufficient conditions are given for at least one closed locally minimal network to exist on a given non-equihedral tetrahedron. Bibliography: 6 titles.

  18. Minimal flow units for magnetohydrodynamic turbulence

    NASA Astrophysics Data System (ADS)

    Orlandi, P.

    2016-08-01

    We present direct numerical simulations of two minimal flow units (MFUs) to investigate the differences between inviscid and viscous simulations, and the different behavior of the evolution for conducting fluids. In these circumstances the introduction of the Lorentz force in the momentum equation produces different scenarios. The Taylor–Green vortex, in the past, was an MFU widely considered for both conducting and non-conducting fluids. The simulations were performed by pseudo-spectral numerical methods; these are repeated here by using a finite difference second-order accurate, energy-conserving scheme for ν =0. Having observed that this initial condition could be inefficient for capturing the eventual occurrence of a finite time singularity a potentially more efficient MFU consisting of two interacting Lamb dipoles was considered. It was found that the two flows have a different time evolution in the vortical dominated stage. In this stage, turbulent structures of different size are generated leading to spectra, in the inviscid conditions, with a {k}-3 range. In real conditions the viscosity produces smaller scales characteristic of fully developed turbulence with energy spectra with well defined exponential and inertial ranges. In the presence of non-conducting conditions the passive vector behaves as the vorticity. The evolution is different in the presence of conducting conditions. Although the time evolution is different, both flows lead to spectra in Kolmogorov units with the same shape at high and intermediate wave numbers.

  19. Minimal modeling of the extratropical general circulation

    NASA Technical Reports Server (NTRS)

    O'Brien, Enda; Branscome, Lee E.

    1989-01-01

    The ability of low-order, two-layer models to reproduce basic features of the mid-latitude general circulation is investigated. Changes in model behavior with increased spectral resolution are examined in detail. Qualitatively correct time-mean heat and momentum balances are achieved in a beta-plane channel model which includes the first and third meridional modes. This minimal resolution also reproduces qualitatively realistic surface and upper-level winds and mean meridional circulations. Higher meridional resolution does not result in substantial changes in the latitudinal structure of the circulation. A qualitatively correct kinetic energy spectrum is produced when the resolution is high enough to include several linearly stable modes. A model with three zonal waves and the first three meridional modes has a reasonable energy spectrum and energy conversion cycle, while also satisfying heat and momentum budget requirements. This truncation reproduces the basic mechanisms and zonal circulation features that are obtained at higher resolution. The model performance improves gradually with higher resolution and is smoothly dependent on changes in external parameters.

  20. Differentially Private Empirical Risk Minimization

    PubMed Central

    Chaudhuri, Kamalika; Monteleoni, Claire; Sarwate, Anand D.

    2011-01-01

    Privacy-preserving machine learning algorithms are crucial for the increasingly common setting in which personal data, such as medical or financial records, are analyzed. We provide general techniques to produce privacy-preserving approximations of classifiers learned via (regularized) empirical risk minimization (ERM). These algorithms are private under the ε-differential privacy definition due to Dwork et al. (2006). First we apply the output perturbation ideas of Dwork et al. (2006), to ERM classification. Then we propose a new method, objective perturbation, for privacy-preserving machine learning algorithm design. This method entails perturbing the objective function before optimizing over classifiers. If the loss and regularizer satisfy certain convexity and differentiability criteria, we prove theoretical results showing that our algorithms preserve privacy, and provide generalization bounds for linear and nonlinear kernels. We further present a privacy-preserving technique for tuning the parameters in general machine learning algorithms, thereby providing end-to-end privacy guarantees for the training process. We apply these results to produce privacy-preserving analogues of regularized logistic regression and support vector machines. We obtain encouraging results from evaluating their performance on real demographic and benchmark data sets. Our results show that both theoretically and empirically, objective perturbation is superior to the previous state-of-the-art, output perturbation, in managing the inherent tradeoff between privacy and learning performance. PMID:21892342

  1. Against Explanatory Minimalism in Psychiatry

    PubMed Central

    Thornton, Tim

    2015-01-01

    The idea that psychiatry contains, in principle, a series of levels of explanation has been criticized not only as empirically false but also, by Campbell, as unintelligible because it presupposes a discredited pre-Humean view of causation. Campbell’s criticism is based on an interventionist-inspired denial that mechanisms and rational connections underpin physical and mental causation, respectively, and hence underpin levels of explanation. These claims echo some superficially similar remarks in Wittgenstein’s Zettel. But attention to the context of Wittgenstein’s remarks suggests a reason to reject explanatory minimalism in psychiatry and reinstate a Wittgensteinian notion of levels of explanation. Only in a context broader than the one provided by interventionism is that the ascription of propositional attitudes, even in the puzzling case of delusions, justified. Such a view, informed by Wittgenstein, can reconcile the idea that the ascription mental phenomena presupposes a particular level of explanation with the rejection of an a priori claim about its connection to a neurological level of explanation. PMID:26696908

  2. Against Explanatory Minimalism in Psychiatry.

    PubMed

    Thornton, Tim

    2015-01-01

    The idea that psychiatry contains, in principle, a series of levels of explanation has been criticized not only as empirically false but also, by Campbell, as unintelligible because it presupposes a discredited pre-Humean view of causation. Campbell's criticism is based on an interventionist-inspired denial that mechanisms and rational connections underpin physical and mental causation, respectively, and hence underpin levels of explanation. These claims echo some superficially similar remarks in Wittgenstein's Zettel. But attention to the context of Wittgenstein's remarks suggests a reason to reject explanatory minimalism in psychiatry and reinstate a Wittgensteinian notion of levels of explanation. Only in a context broader than the one provided by interventionism is that the ascription of propositional attitudes, even in the puzzling case of delusions, justified. Such a view, informed by Wittgenstein, can reconcile the idea that the ascription mental phenomena presupposes a particular level of explanation with the rejection of an a priori claim about its connection to a neurological level of explanation. PMID:26696908

  3. Minimalism through intraoperative functional mapping.

    PubMed

    Berger, M S

    1996-01-01

    Intraoperative stimulation mapping may be used to avoid unnecessary risk to functional regions subserving language and sensori-motor pathways. Based on the data presented here, language localization is variable in the entire population, with only certainty existing for the inferior frontal region responsible for motor speech. Anatomical landmarks such as the anterior temporal tip for temporal lobe language sites and the posterior aspect of the lateral sphenoid wing for the frontal lobe language zones are unreliable in avoiding postoperative aphasias. Thus, individual mapping to identify essential language sites has the greatest likelihood of avoiding permanent deficits in naming, reading, and motor speech. In a similar approach, motor and sensory pathways from the cortex and underlying white matter may be reliably stimulated and mapped in both awake and asleep patients. Although these techniques require an additional operative time and equipment nominally priced, the result is often gratifying, as postoperative morbidity has been greatly reduced in the process of incorporating these surgical strategies. The patients quality of life is improved in terms of seizure control, with or without antiepileptic drugs. This avoids having to perform a second costly operative procedure, which is routinely done when extraoperative stimulation and recording is done via subdural grids. In addition, an aggressive tumor resection at the initial operation lengthens the time to tumor recurrence and often obviates the need for a subsequent reoperation. Thus, intraoperative functional mapping may be best alluded to as a surgical technique that results in "minimalism in the long term". PMID:9247814

  4. Minimally invasive medial hip approach.

    PubMed

    Chiron, P; Murgier, J; Cavaignac, E; Pailhé, R; Reina, N

    2014-10-01

    The medial approach to the hip via the adductors, as described by Ludloff or Ferguson, provides restricted visualization and incurs a risk of neurovascular lesion. We describe a minimally invasive medial hip approach providing broader exposure of extra- and intra-articular elements in a space free of neurovascular structures. With the lower limb in a "frog-leg" position, the skin incision follows the adductor longus for 6cm and then the aponeurosis is incised. A slide plane between all the adductors and the aponeurosis is easily released by blunt dissection, with no interposed neurovascular elements. This gives access to the lesser trochanter, psoas tendon and inferior sides of the femoral neck and head, anterior wall of the acetabulum and labrum. We report a series of 56 cases, with no major complications: this approach allows treatment of iliopsoas muscle lesions and resection or filling of benign tumors of the cervical region and enables intra-articular surgery (arthrolysis, resection of osteophytes or foreign bodies, labral suture). PMID:25164350

  5. Minimal complexity control law synthesis

    NASA Technical Reports Server (NTRS)

    Bernstein, Dennis S.; Haddad, Wassim M.; Nett, Carl N.

    1989-01-01

    A paradigm for control law design for modern engineering systems is proposed: Minimize control law complexity subject to the achievement of a specified accuracy in the face of a specified level of uncertainty. Correspondingly, the overall goal is to make progress towards the development of a control law design methodology which supports this paradigm. Researchers achieve this goal by developing a general theory of optimal constrained-structure dynamic output feedback compensation, where here constrained-structure means that the dynamic-structure (e.g., dynamic order, pole locations, zero locations, etc.) of the output feedback compensation is constrained in some way. By applying this theory in an innovative fashion, where here the indicated iteration occurs over the choice of the compensator dynamic-structure, the paradigm stated above can, in principle, be realized. The optimal constrained-structure dynamic output feedback problem is formulated in general terms. An elegant method for reducing optimal constrained-structure dynamic output feedback problems to optimal static output feedback problems is then developed. This reduction procedure makes use of star products, linear fractional transformations, and linear fractional decompositions, and yields as a byproduct a complete characterization of the class of optimal constrained-structure dynamic output feedback problems which can be reduced to optimal static output feedback problems. Issues such as operational/physical constraints, operating-point variations, and processor throughput/memory limitations are considered, and it is shown how anti-windup/bumpless transfer, gain-scheduling, and digital processor implementation can be facilitated by constraining the controller dynamic-structure in an appropriate fashion.

  6. On Modelling Minimal Disease Activity

    PubMed Central

    Jackson, Christopher H.; Su, Li; Gladman, Dafna D.

    2016-01-01

    Objective To explore methods for statistical modelling of minimal disease activity (MDA) based on data from intermittent clinic visits. Methods The analysis was based on a 2‐state model. Comparisons were made between analyses based on “complete case” data from visits at which MDA status was known, and the use of hidden model methodology that incorporated information from visits at which only some MDA defining criteria could be established. Analyses were based on an observational psoriatic arthritis cohort. Results With data from 856 patients and 7,024 clinic visits, analysis was based on virtually all visits, although only 62.6% provided enough information to determine MDA status. Estimated mean times for an episode of MDA varied from 4.18 years to 3.10 years, with smaller estimates derived from the hidden 2‐state model analysis. Over a 10‐year period, the estimated expected times spent in MDA episodes of longer than 1 year was 3.90 to 4.22, and the probability of having such an MDA episode was estimated to be 0.85 to 0.91, with longer times and greater probabilities seen with the hidden 2‐state model analysis. Conclusion A 2‐state model provides a useful framework for the analysis of MDA. Use of data from visits at which MDA status can not be determined provide more precision, and notable differences are seen in estimated quantities related to MDA episodes based on complete case and hidden 2‐state model analyses. The possibility of bias, as well as loss of precision, should be recognized when complete case analyses are used. PMID:26315478

  7. In the Opponent's Shoes: Increasing the Behavioral Validity of Attackers' Judgments in Counterterrorism Models.

    PubMed

    Sri Bhashyam, Sumitra; Montibeller, Gilberto

    2016-04-01

    A key objective for policymakers and analysts dealing with terrorist threats is trying to predict the actions that malicious agents may take. A recent trend in counterterrorism risk analysis is to model the terrorists' judgments, as these will guide their choices of such actions. The standard assumptions in most of these models are that terrorists are fully rational, following all the normative desiderata required for rational choices, such as having a set of constant and ordered preferences, being able to perform a cost-benefit analysis of their alternatives, among many others. However, are such assumptions reasonable from a behavioral perspective? In this article, we analyze the types of assumptions made across various counterterrorism analytical models that represent malicious agents' judgments and discuss their suitability from a descriptive point of view. We then suggest how some of these assumptions could be modified to describe terrorists' preferences more accurately, by drawing knowledge from the fields of behavioral decision research, politics, philosophy of choice, public choice, and conflict management in terrorism. Such insight, we hope, might help make the assumptions of these models more behaviorally valid for counterterrorism risk analysis. PMID:26040996

  8. A Framework for Behavior-Based Malware Analysis in the Cloud

    NASA Astrophysics Data System (ADS)

    Martignoni, Lorenzo; Paleari, Roberto; Bruschi, Danilo

    To ease the analysis of potentially malicious programs, dynamic behavior-based techniques have been proposed in the literature. Unfortunately, these techniques often give incomplete results because the execution environments in which they are performed are synthetic and do not faithfully resemble the environments of end-users, the intended targets of the malicious activities. In this paper, we present a new framework for improving behavior-based analysis of suspicious programs. Our framework allows an end-user to delegate security labs, the cloud, the execution and the analysis of a program and to force the program to behave as if it were executed directly in the environment of the former. The evaluation demonstrated that the proposed framework allows security labs to improve the completeness of the analysis, by analyzing a piece of malware on behalf of multiple end-users simultaneously, while performing a fine-grained analysis of the behavior of the program with no computational cost for end-users.

  9. A strategy for minimizing common mode human error in executing critical functions and tasks

    SciTech Connect

    Beltracchi, L.; Lindsay, R.W.

    1992-05-01

    Human error in execution of critical functions and tasks can be costly. The Three Mile Island and the Chernobyl Accidents are examples of results from human error in the nuclear industry. There are similar errors that could no doubt be cited from other industries. This paper discusses a strategy to minimize common mode human error in the execution of critical functions and tasks. The strategy consists of the use of human redundancy, and also diversity in human cognitive behavior: skill-, rule-, and knowledge-based behavior. The authors contend that the use of diversity in human cognitive behavior is possible, and it minimizes common mode error.

  10. A strategy for minimizing common mode human error in executing critical functions and tasks

    SciTech Connect

    Beltracchi, L. ); Lindsay, R.W. )

    1992-01-01

    Human error in execution of critical functions and tasks can be costly. The Three Mile Island and the Chernobyl Accidents are examples of results from human error in the nuclear industry. There are similar errors that could no doubt be cited from other industries. This paper discusses a strategy to minimize common mode human error in the execution of critical functions and tasks. The strategy consists of the use of human redundancy, and also diversity in human cognitive behavior: skill-, rule-, and knowledge-based behavior. The authors contend that the use of diversity in human cognitive behavior is possible, and it minimizes common mode error.