Beat frequency ultrasonic microsphere contrast agent detection system

NASA Technical Reports Server (NTRS)

Pretlow, Robert A., III (Inventor); Yost, William T. (Inventor); Cantrell, John H., Jr. (Inventor)

1995-01-01

A system for and method of detecting and measuring concentrations of an ultrasonically-reflective microsphere contrast agent involving detecting non-linear sum and difference beat frequencies produced by the microspheres when two impinging signals with non-identical frequencies are combined by mixing. These beat frequencies can be used for a variety of applications such as detecting the presence of and measuring the flow rates of biological fluids and industrial liquids, including determining the concentration level of microspheres in the myocardium.

Beat frequency ultrasonic microsphere contrast agent detection system

NASA Technical Reports Server (NTRS)

Pretlow, III, Robert A. (Inventor); Yost, William T. (Inventor); Cantrell, Jr., John H. (Inventor)

1997-01-01

A system for and method of detecting and measuring concentrations of an ultrasonically-reflective microsphere contrast agent involving detecting non-linear sum and difference beat frequencies produced by the microspheres when two impinging signals with non-identical frequencies are combined by mixing. These beat frequencies can be used for a variety of applications such as detecting the presence of and measuring the flow rates of biological fluids and industrial liquids, including determining the concentration level of microspheres in the myocardium.

Toward detecting deception in intelligent systems

NASA Astrophysics Data System (ADS)

Santos, Eugene, Jr.; Johnson, Gregory, Jr.

2004-08-01

Contemporary decision makers often must choose a course of action using knowledge from several sources. Knowledge may be provided from many diverse sources including electronic sources such as knowledge-based diagnostic or decision support systems or through data mining techniques. As the decision maker becomes more dependent on these electronic information sources, detecting deceptive information from these sources becomes vital to making a correct, or at least more informed, decision. This applies to unintentional disinformation as well as intentional misinformation. Our ongoing research focuses on employing models of deception and deception detection from the fields of psychology and cognitive science to these systems as well as implementing deception detection algorithms for probabilistic intelligent systems. The deception detection algorithms are used to detect, classify and correct attempts at deception. Algorithms for detecting unexpected information rely upon a prediction algorithm from the collaborative filtering domain to predict agent responses in a multi-agent system.

Tuning the properties of conjugated polyelectrolytes and application in a biosensor platform

DOEpatents

Chen, Liaohai

2004-05-18

The present invention provides a method of detecting a biological agent including contacting a sample with a sensor including a polymer system capable of having an alterable measurable property from the group of luminescence, anisotropy, redox potential and uv/vis absorption, the polymer system including an ionic conjugated polymer and an electronically inert polyelectrolyte having a biological agent recognition element bound thereto, the electronically inert polyelectrolyte adapted for undergoing a conformational structural change upon exposure to a biological agent having affinity for binding to the recognition element bound to the electronically inert polyelectrolyte, and, detecting the detectable change in the alterable measurable property. A chemical moiety being the reaction product of (i) a polyelectrolyte monomer and (ii) a biological agent recognition element-substituted polyelectrolyte monomer is also provided.

New method for comprehensive detection of chemical warfare agents using an electron-cyclotron-resonance ion-source mass spectrometer

NASA Astrophysics Data System (ADS)

Kidera, Masanori; Seto, Yasuo; Takahashi, Kazuya; Enomoto, Shuichi; Kishi, Shintaro; Makita, Mika; Nagamatsu, Tsuyoshi; Tanaka, Tatsuhiko; Toda, Masayoshi

2011-03-01

We developed a detection technology for vapor forms of chemical warfare agents (CWAs) with an element analysis system using an electron cyclotron resonance ion source. After the vapor sample was introduced directly into the ion source, the molecular material was decomposed into elements using electron cyclotron resonance plasma and ionized. The following CWAs and stimulants were examined: diisopropyl fluorophosphonate (DFP), 2-chloroethylethylsulfide (2CEES), cyanogen chloride (CNCl), and hydrogen cyanide (HCN). The type of chemical warfare agents, specifically, whether it was a nerve agent, blister agent, blood agent, or choking agent, could be determined by measuring the quantities of the monatomic ions or CN + using mass spectrometry. It was possible to detect gaseous CWAs that could not be detected by a conventional mass spectrometer. The distribution of electron temperature in the plasma could be closely controlled by adjusting the input power of the microwaves used to generate the electron cyclotron resonance plasma, and the target compounds could be detected as molecular ions or fragment ions, enabling identification of the target agents.

[THE DEVELOPMENT OF IMMUNE ENZYME AND IMMUNE CHROMATOGRAPHIC MONOCLONAL TEST-SYSTEM FOR DETECTING TULAREMIA AGENT].

PubMed

Eremkin, A V; Elagin, G D; Petchenkin, D V; Fomenkov, O O; Bogatcheva, N V; Kitmanov, A A; Kuklina, G V; Tikhvinskaya, O V

2016-03-01

The immune enzyme and immunochromatographic test-systems for detecting tularemia agent were developed on the basis of selected set of monoclonal antibodies having immunochemical activity to antigens Francisella tularensis. The evaluation of sensitivity and specificity of developed test-systems demonstrated that samples provided detection of strains of F. tularensis in concentration from 5.0 x 105 mkxcm-3 to 1.0 x 106 mkxcm-3 and gave no false positive results in analysis of heterologous microorganisms in concentration of 1.0 x 108 mkxcm-3.

Portable Analytical Systems for On-Site Diagnosis of Exposure to Pesticides and Nerve Agents

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lin, Yuehe; Wang, Jun; Liu, Guodong

In this chapter, we summarize recent work in our laboratory on the development of sensitive portable analytical systems for use in on-site detection of exposure to organophosphate (OP) pesticides and chemical nerve agents. These systems are based on various nanomaterials functioning as transducers; recognition agents or labels and various elelectrochemical/immunoassay techniques. The studied nanomaterials included functionalized carbon nanotubes (CNT), zirconia nanoparticles (NPs) and quantum dots (QDs). Three biomarkers e.g. the free OPs, metabolites of OPs and protein-OP adducts in biological matrices have been employed for biomonitoring of OP exposure with our developed system. It has been found that the nanomaterial-basedmore » portable analytical systems have high sensitivity for the detection of the biomarkers, which suggest that these technologies offer great promise for the rapid and on-site detection and evaluation of OP exposure.« less

Methods, microfluidic devices, and systems for detection of an active enzymatic agent

DOEpatents

Sommer, Gregory J; Hatch, Anson V; Singh, Anup K; Wang, Ying-Chih

2014-10-28

Embodiments of the present invention provide methods, microfluidic devices, and systems for the detection of an active target agent in a fluid sample. A substrate molecule is used that contains a sequence which may cleave in the presence of an active target agent. A SNAP25 sequence is described, for example, that may be cleaved in the presence of Botulinum Neurotoxin. The substrate molecule includes a reporter moiety. The substrate molecule is exposed to the sample, and resulting reaction products separated using electrophoretic separation. The elution time of the reporter moiety may be utilized to identify the presence or absence of the active target agent.

Enhanced situational awareness in the maritime domain: an agent-based approach for situation management

NASA Astrophysics Data System (ADS)

Brax, Christoffer; Niklasson, Lars

2009-05-01

Maritime Domain Awareness is important for both civilian and military applications. An important part of MDA is detection of unusual vessel activities such as piracy, smuggling, poaching, collisions, etc. Today's interconnected sensorsystems provide us with huge amounts of information over large geographical areas which can make the operators reach their cognitive capacity and start to miss important events. We propose and agent-based situation management system that automatically analyse sensor information to detect unusual activity and anomalies. The system combines knowledge-based detection with data-driven anomaly detection. The system is evaluated using information from both radar and AIS sensors.

Quantitative detection of pathogens in centrifugal microfluidic disks

DOE Office of Scientific and Technical Information (OSTI.GOV)

Koh, Chung-Yan; Schaff, Ulrich Y.; Sommer, Gregory Jon

A system and methods for detection of a nucleic acid including forming a plurality of nucleic acid detection complexes are described, each of the complexes including a nucleic acid analyte, a detection agent and a functionalized probe. The method further including binding the nucleic acid detection complexes to a plurality of functionalized particles in a fluid sample and separating the functionalized particles having the nucleic acid detection complexes bound thereto from the fluid sample using a density media. The nucleic acid analyte is detected by detecting the detection agent.

Hybrid Modified K-Means with C4.5 for Intrusion Detection Systems in Multiagent Systems

PubMed Central

Laftah Al-Yaseen, Wathiq; Ali Othman, Zulaiha; Ahmad Nazri, Mohd Zakree

2015-01-01

Presently, the processing time and performance of intrusion detection systems are of great importance due to the increased speed of traffic data networks and a growing number of attacks on networks and computers. Several approaches have been proposed to address this issue, including hybridizing with several algorithms. However, this paper aims at proposing a hybrid of modified K-means with C4.5 intrusion detection system in a multiagent system (MAS-IDS). The MAS-IDS consists of three agents, namely, coordinator, analysis, and communication agent. The basic concept underpinning the utilized MAS is dividing the large captured network dataset into a number of subsets and distributing these to a number of agents depending on the data network size and core CPU availability. KDD Cup 1999 dataset is used for evaluation. The proposed hybrid modified K-means with C4.5 classification in MAS is developed in JADE platform. The results show that compared to the current methods, the MAS-IDS reduces the IDS processing time by up to 70%, while improving the detection accuracy. PMID:26161437

Hybrid Modified K-Means with C4.5 for Intrusion Detection Systems in Multiagent Systems.

PubMed

Laftah Al-Yaseen, Wathiq; Ali Othman, Zulaiha; Ahmad Nazri, Mohd Zakree

2015-01-01

Presently, the processing time and performance of intrusion detection systems are of great importance due to the increased speed of traffic data networks and a growing number of attacks on networks and computers. Several approaches have been proposed to address this issue, including hybridizing with several algorithms. However, this paper aims at proposing a hybrid of modified K-means with C4.5 intrusion detection system in a multiagent system (MAS-IDS). The MAS-IDS consists of three agents, namely, coordinator, analysis, and communication agent. The basic concept underpinning the utilized MAS is dividing the large captured network dataset into a number of subsets and distributing these to a number of agents depending on the data network size and core CPU availability. KDD Cup 1999 dataset is used for evaluation. The proposed hybrid modified K-means with C4.5 classification in MAS is developed in JADE platform. The results show that compared to the current methods, the MAS-IDS reduces the IDS processing time by up to 70%, while improving the detection accuracy.

Detection of biological warfare agents using ultra violet-laser induced fluorescence LIDAR

NASA Astrophysics Data System (ADS)

Joshi, Deepti; Kumar, Deepak; Maini, Anil K.; Sharma, Ramesh C.

This review has been written to highlight the threat of biological warfare agents, their types and detection. Bacterial biological agent Bacillus anthracis (bacteria causing the disease anthrax) which is most likely to be employed in biological warfare is being discussed in detail. Standoff detection of biological warfare agents in aerosol form using Ultra violet-Laser Induced Fluorescence (UV-LIF) spectroscopy method has been studied. Range-resolved detection and identification of biological aerosols by both nano-second and non-linear femto-second LIDAR is also discussed. Calculated received fluorescence signal for a cloud of typical biological agent Bacillus globigii (Simulants of B. anthracis) at a location of ˜5.0 km at different concentrations in presence of solar background radiation has been described. Overview of current research efforts in internationally available working UV-LIF LIDAR systems are also mentioned briefly.

[Identification of Circulating Tumor Cell（CTC）in Breast Cancer Patients Using a Newly Established CTC Detecting System].

PubMed

Nagata, Takuya; Ohnaga, Takashi; Lu, Xiao Long; Watanabe, Toru; Hirano, Katsuhisa; Okumura, Tomoyuki; Tsukada, Kazuhiro

2015-10-01

We developed a new circulating tumor cell (CTC) chip in order to identify CTCs in the peripheral blood of cancer patients. In this study, we aimed to identify CTCs in the blood of breast cancer patients by using this CTC detecting system. In addition, we used this system to evaluate the response to anticancer agents. We were able to identify CTCs in 5 of 6 patients. In addition, the system showed that the number of CTCs had decreased after chemotherapy. Thus, the CTC detecting system was useful in the identification of CTCs in the breast cancer patients and in the early prediction of response to anticancer agents.

Enhancement of the conductivity detection signal in capillary electrophoresis systems using neutral cyclodextrins as sweeping agents.

PubMed

Boublík, Milan; Riesová, Martina; Dubský, Pavel; Gaš, Bohuslav

2018-06-01

Conductivity detection is a universal detection technique often encountered in electrophoretic separation systems, especially in modern chip-electrophoresis based devices. On the other hand, it is sparsely combined with another contemporary trend of enhancing limits of detection by means of various preconcentration strategies. This can be attributed to the fact that a preconcentration experimental setup usually brings about disturbances in a conductivity baseline. Sweeping with a neutral sweeping agent seems a good candidate for overcoming this problem. A neutral sweeping agent does not hinder the conductivity detection while a charged analyte may preconcentrate on its boundary due to a decrease in its effective mobility. This study investigates such sweeping systems theoretically, by means of computer simulations, and experimentally. A formula is provided for the reliable estimation of the preconcentration factor. Additionally, it is demonstrated that the conductivity signal can significantly benefit from slowing down the analyte and thus the overall signal enhancement can easily overweight amplification caused solely by the sweeping process. The overall enhancement factor can be deduced a priori from the linearized theory of electrophoresis implemented in the PeakMaster freeware. Sweeping by neutral cyclodextrin is demonstrated on an amplification of a conductivity signal of flurbiprofen in a real drug sample. Finally, a possible formation of unexpected system peaks in systems with a neutral sweeping agent is revealed by the computer simulation and confirmed experimentally. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

An artificial bioindicator system for network intrusion detection.

PubMed

Blum, Christian; Lozano, José A; Davidson, Pedro Pinacho

An artificial bioindicator system is developed in order to solve a network intrusion detection problem. The system, inspired by an ecological approach to biological immune systems, evolves a population of agents that learn to survive in their environment. An adaptation process allows the transformation of the agent population into a bioindicator that is capable of reacting to system anomalies. Two characteristics stand out in our proposal. On the one hand, it is able to discover new, previously unseen attacks, and on the other hand, contrary to most of the existing systems for network intrusion detection, it does not need any previous training. We experimentally compare our proposal with three state-of-the-art algorithms and show that it outperforms the competing approaches on widely used benchmark data.

Microfluidic chip with optical sensor for rapid detection of nerve agent Sarin in water samples

NASA Astrophysics Data System (ADS)

Tan, Hsih Yin; Nguyen, Nam-Trung; Loke, Weng Keong; Tan, Yong Teng

2007-12-01

The chemical warfare agent Sarin is an organophosphate that is highly toxic to humans as they can act as cholinesterase inhibitors, that disrupts neuromuscular transmission. As these nerve agents are colorless, odorless and highly toxic, they can be introduced into drinking water as a means of terrorist sabotage. Hence, numerous innovative devices and methods have been developed for rapid detection of these organophosphates. Microfluidic technology allows the implementation of fast and sensitive detection of Sarin. In this paper, a micro-total analysis systems (TAS), also known as Lab-on-a-chip, fitted with an optical detection system has been developed to analyze the presence of the nerve agent sarin in water samples. In the present set-up, inhibition of co-introduced cholinesterase and water samples containing trace amounts of nerve agent sarin into the microfluidic device was used as the basis for selective detection of sarin. The device was fabricated using polymeric micromachining with PMMA (poly (methymethacrylate)) as the substrate material. A chromophore was utilized to measure the activity of remnant cholinesterase activity, which is inversely related to the amount of sarin present in the water samples. Comparisons were made between two different optical detection techniques and the findings will be presented in this paper. The presented measurement method is simple, fast and as sensitive as Gas Chromatography.

Using Nanotechnology to Detect Nerve Agents

DTIC Science & Technology

2011-01-01

56 | Air & Space Power Journal Air Force Institute of Technology Using Nanotechnology to Detect Nerve Agents Lt Col Mark N. Goltz , PhD, USAF...Retired Dr. Dong Shik Kim Maj LeeAnn Racz, PhD, USAF* *Lieutenant Colonel Goltz and Major Racz are faculty members in the Department of Systems and

Chemical warfare agent detection: a review of current trends and future perspective.

PubMed

Pacsial-Ong, Eden Joy; Aguilar, Zoraida P

2013-01-01

The World Health Organization recommends countries to create a public health system that can respond to the deliberate release of chemical warfare agents (CWAs). Procedures for preparedness, response, decontamination protocols and medical countermeasures against CWA attacks are described. Known CWAs, including their properties and pharmacological consequences upon exposure, are tabulated and discussed. Requirements imposed on detection systems by various applications and environmental needs are presented in order to assess the devices for detection and identification of specific CWAs. The review surveys current and near-term detection technologies and equipments, as well as devices that are currently available to the military and civilian first responders. Brief technical discussions of several detection technologies are presented, with emphasis placed in the principles of detection. Finally, enabling technologies that form the basis for advanced sensing systems and devices are described.

Detection of biological warfare agents using ultra violet-laser induced fluorescence LIDAR.

PubMed

Joshi, Deepti; Kumar, Deepak; Maini, Anil K; Sharma, Ramesh C

2013-08-01

This review has been written to highlight the threat of biological warfare agents, their types and detection. Bacterial biological agent Bacillus anthracis (bacteria causing the disease anthrax) which is most likely to be employed in biological warfare is being discussed in detail. Standoff detection of biological warfare agents in aerosol form using Ultra violet-Laser Induced Fluorescence (UV-LIF) spectroscopy method has been studied. Range-resolved detection and identification of biological aerosols by both nano-second and non-linear femto-second LIDAR is also discussed. Calculated received fluorescence signal for a cloud of typical biological agent Bacillus globigii (Simulants of B. anthracis) at a location of ~5.0 km at different concentrations in presence of solar background radiation has been described. Overview of current research efforts in internationally available working UV-LIF LIDAR systems are also mentioned briefly. Copyright © 2013 Elsevier B.V. All rights reserved.

Sensor Systems for Biological Agent Attacks: Protecting Buildings and Military Bases

DTIC Science & Technology

2004-01-01

simple aerosol detectors, to those that identify an agent based on its genetic, structural, or chemical properties , to so- called "functional...Cytometry, 122 Target Binding That Changes Detectable Properties of Smart Sensor Surfaces, 124 Colorimetric Detection, 124 Fluorescence Detection, 125 One...microscopy. In addition to particles directly derived from living organisms, other particles in air may also share properties with the bioaerosols

Consensus pursuit of heterogeneous multi-agent systems under a directed acyclic graph

NASA Astrophysics Data System (ADS)

Yan, Jing; Guan, Xin-Ping; Luo, Xiao-Yuan

2011-04-01

This paper is concerned with the cooperative target pursuit problem by multiple agents based on directed acyclic graph. The target appears at a random location and moves only when sensed by the agents, and agents will pursue the target once they detect its existence. Since the ability of each agent may be different, we consider the heterogeneous multi-agent systems. According to the topology of the multi-agent systems, a novel consensus-based control law is proposed, where the target and agents are modeled as a leader and followers, respectively. Based on Mason's rule and signal flow graph analysis, the convergence conditions are provided to show that the agents can catch the target in a finite time. Finally, simulation studies are provided to verify the effectiveness of the proposed approach.

Development of a persistent chemical agent simulation system

NASA Technical Reports Server (NTRS)

1983-01-01

A Persistent Chemical Agent Simulation System was developed (PCASS) to simulate, for force-on-force training exercises, the field environment produced by the presence of persistent chemical agents. Such a simulant system must satisfy several requirements to be of value as a training aid. Specifically, it must provide for realistic training which will generate competency in at least the following areas: (1) detection of the persistent agent presence; (2) proper use of protective equipment and procedures; (3) determination of the extent of contamination; and (4) decontamination of equipment and personnel.

Path scanning for the detection of anomalous subgraphs and use of DNS requests and host agents for anomaly/change detection and network situational awareness

DOE Office of Scientific and Technical Information (OSTI.GOV)

Neil, Joshua Charles; Fisk, Michael Edward; Brugh, Alexander William

A system, apparatus, computer-readable medium, and computer-implemented method are provided for detecting anomalous behavior in a network. Historical parameters of the network are determined in order to determine normal activity levels. A plurality of paths in the network are enumerated as part of a graph representing the network, where each computing system in the network may be a node in the graph and the sequence of connections between two computing systems may be a directed edge in the graph. A statistical model is applied to the plurality of paths in the graph on a sliding window basis to detect anomalousmore » behavior. Data collected by a Unified Host Collection Agent ("UHCA") may also be used to detect anomalous behavior.« less

Department of Defense Chemical and Biological Defense Program. Volume I: Annual Report to Congress

DTIC Science & Technology

2002-04-01

The M21 RSCAAL is an automatic scanning, passive infrared sensor that detects nerve ( GA , GB, and GD) and blister (H and L) agent vapor clouds based on...Point Detection GA - tabun, a nerve agent System GAO - General Accounting Office IPE - Individual Protective Equipment GAS - Group A Streptococcus...IPR - In-Process Review GB - sarin , a nerve agent IPT - Integrated Product Team GC - gas chromatography IR&D - Independent Research & Development GD

An industrial information integration approach to in-orbit spacecraft

NASA Astrophysics Data System (ADS)

Du, Xiaoning; Wang, Hong; Du, Yuhao; Xu, Li Da; Chaudhry, Sohail; Bi, Zhuming; Guo, Rong; Huang, Yongxuan; Li, Jisheng

2017-01-01

To operate an in-orbit spacecraft, the spacecraft status has to be monitored autonomously by collecting and analysing real-time data, and then detecting abnormities and malfunctions of system components. To develop an information system for spacecraft state detection, we investigate the feasibility of using ontology-based artificial intelligence in the system development. We propose a new modelling technique based on the semantic web, agent, scenarios and ontologies model. In modelling, the subjects of astronautics fields are classified, corresponding agents and scenarios are defined, and they are connected by the semantic web to analyse data and detect failures. We introduce the modelling methodologies and the resulted framework of the status detection information system in this paper. We discuss system components as well as their interactions in details. The system has been prototyped and tested to illustrate its feasibility and effectiveness. The proposed modelling technique is generic which can be extended and applied to the system development of other large-scale and complex information systems.

NBC detection in air and water

NASA Technical Reports Server (NTRS)

Hartley, Frank T.; Smith, Steven J.; McMurtry, Gary M.

2003-01-01

Participating in a Navy STTR project to develop a system capable of the 'real-time' detection and quanitification of nuclear, biological and chemical (NBC) warfare agents, and of related industrial chemicals including NBC agent synthesis by-products in water and in air immediately above the water's surface. This project uses JPL's Soft Ionization Membrane (SIM) technology which totally ionizes molecules without fragmentation (a process that can markedly improve the sensitivity and specificity of molecule compostition identification), and JPL's Rotating Field Mass Spectrometer (RFMS) technology which has large enough dynamic mass range to enable detection of nuclear materials as well as biological and chemical agents. This Navy project integrates these JPL Environmental Monitoring UnitS (REMUS) an autonomous underwater vehicle (AUV). It is anticipated that the REMUS AUV will be capable of 'real-time' detection and quantification of NBC warefare agents.

A smart room for hospitalised elderly people: essay of modelling and first steps of an experiment.

PubMed

Rialle, V; Lauvernay, N; Franco, A; Piquard, J F; Couturier, P

1999-01-01

We present a study of modelling and the first steps of an experiment of a smart room for hospitalised elderly people. The system aims at detecting falls and sicknesses, and implements four main functions: perception of patient and environment through sensors, reasoning from perceived events and patient clinical findings, action by way of alarm triggering and message passing to medical staff, and adaptation to various patient profiles, sensor layouts, house fixtures and architecture. It includes a physical multisensory device located in the patient's room, and a multi-agent system for fall detection and alarm triggering. This system encompasses a perception agent, and a reasoning agent. The latter has two complementary capacities implemented by sub-agents: deduction of type of alarm from incoming events, and knowledge induction from recorded events. The system has been tested with a few patients in real clinical situation, and the first experiment provides encouraging results which are described in a precise manner.

Motion Planning in a Society of Intelligent Mobile Agents

NASA Technical Reports Server (NTRS)

Esterline, Albert C.; Shafto, Michael (Technical Monitor)

2002-01-01

The majority of the work on this grant involved formal modeling of human-computer integration. We conceptualize computer resources as a multiagent system so that these resources and human collaborators may be modeled uniformly. In previous work we had used modal for this uniform modeling, and we had developed a process-algebraic agent abstraction. In this work, we applied this abstraction (using CSP) in uniformly modeling agents and users, which allowed us to use tools for investigating CSP models. This work revealed the power of, process-algebraic handshakes in modeling face-to-face conversation. We also investigated specifications of human-computer systems in the style of algebraic specification. This involved specifying the common knowledge required for coordination and process-algebraic patterns of communication actions intended to establish the common knowledge. We investigated the conditions for agents endowed with perception to gain common knowledge and implemented a prototype neural-network system that allows agents to detect when such conditions hold. The literature on multiagent systems conceptualizes communication actions as speech acts. We implemented a prototype system that infers the deontic effects (obligations, permissions, prohibitions) of speech acts and detects violations of these effects. A prototype distributed system was developed that allows users to collaborate in moving proxy agents; it was designed to exploit handshakes and common knowledge Finally. in work carried over from a previous NASA ARC grant, about fifteen undergraduates developed and presented projects on multiagent motion planning.

Wearable Flexible and Stretchable Glove Biosensor for On-Site Detection of Organophosphorus Chemical Threats

DTIC Science & Technology

2017-03-03

finger enables rapid on-site detection of organophosphate (OP) nerve-agent compounds on suspicious surfaces and agricultural products following their...used as pesticides in agricultural and domestic settings.21,22 These OP neurotoxins severely affect the nervous system and lead to rapid death. Due to...The “on-hand” detection of different OP chemical agents on a variety of surfaces and agricultural foodstuffs demonstrate that the new wireless glove

Standoff detection of explosives and chemical agents using broadly tuned external-cavity quantum cascade lasers (EC-QCLs)

NASA Astrophysics Data System (ADS)

Takeuchi, Eric B.; Rayner, Timothy; Weida, Miles; Crivello, Salvatore; Day, Timothy

2007-10-01

Civilian soft targets such as transportation systems are being targeted by terrorists using IEDs and suicide bombers. Having the capability to remotely detect explosives, precursors and other chemicals would enable these assets to be protected with minimal interruption of the flow of commerce. Mid-IR laser technology offers the potential to detect explosives and other chemicals in real-time and from a safe standoff distance. While many of these agents possess "fingerprint" signatures in the mid-IR (i.e. in the 3-20 micron regime), their effective interrogation by a practical, field-deployable system has been limited by size, complexity, reliability and cost constraints of the base laser technology. Daylight Solutions has addressed these shortcomings by developing compact, portable, broadly tunable mid-IR laser sources based upon external-cavity quantum cascade technology. This technology is now being applied by Daylight in system level architectures for standoff and remote detection of explosives, precursors and chemical agents. Several of these architectures and predicted levels of performance will be presented.

FTIR gas analysis with improved sensitivity and selectivity for CWA and TIC detection

NASA Astrophysics Data System (ADS)

Phillips, Charles M.; Tan, Huwei

2010-04-01

This presentation describes the use of an FTIR (Fourier Transform Infrared)-based spectrometer designed to continuously monitor ambient air for the presence of chemical warfare agents (CWAs) and toxic industrial chemicals (TICs). The necessity of a reliable system capable of quickly and accurately detecting very low levels of CWAs and TICs while simultaneously retaining a negligible false alarm rate will be explored. Technological advancements in FTIR sensing have reduced noise while increasing selectivity and speed of detection. These novel analyzer design characteristics are discussed in detail and descriptions are provided which show how optical throughput, gas cell form factor, and detector response are optimized. The hardware and algorithms described here will explain why this FTIR system is very effective for the simultaneous detection and speciation of a wide variety of toxic compounds at ppb concentrations. Analytical test data will be reviewed demonstrating the system's sensitivity to and selectivity for specific CWAs and TICs; this will include recent data acquired as part of the DHS ARFCAM (Autonomous Rapid Facility Chemical Agent Monitor) project. These results include analyses of the data from live agent testing for the determination of CWA detection limits, immunity to interferences, detection times, residual noise analysis and false alarm rates. Sensing systems such as this are critical for effective chemical hazard identification which is directly relevant to the CBRNE community.

Development of a Fish Cell Biosensor System for Genotoxicity Detection Based on DNA Damage-Induced Trans-Activation of p21 Gene Expression

PubMed Central

Geng, Deyu; Zhang, Zhixia; Guo, Huarong

2012-01-01

p21CIP1/WAF1 is a p53-target gene in response to cellular DNA damage. Here we report the development of a fish cell biosensor system for high throughput genotoxicity detection of new drugs, by stably integrating two reporter plasmids of pGL3-p21-luc (human p21 promoter linked to firefly luciferase) and pRL-CMV-luc (CMV promoter linked to Renilla luciferase) into marine flatfish flounder gill (FG) cells, referred to as p21FGLuc. Initial validation of this genotoxicity biosensor system showed that p21FGLuc cells had a wild-type p53 signaling pathway and responded positively to the challenge of both directly acting genotoxic agents (bleomycin and mitomycin C) and indirectly acting genotoxic agents (cyclophosphamide with metabolic activation), but negatively to cyclophosphamide without metabolic activation and the non-genotoxic agents ethanol and D-mannitol, thus confirming a high specificity and sensitivity, fast and stable response to genotoxic agents for this easily maintained fish cell biosensor system. This system was especially useful in the genotoxicity detection of Di(2-ethylhexyl) phthalate (DEHP), a rodent carcinogen, but negatively reported in most non-mammalian in vitro mutation assays, by providing a strong indication of genotoxicity for DEHP. A limitation for this biosensor system was that it might give false positive results in response to sodium butyrate and any other agents, which can trans-activate the p21 gene in a p53-independent manner. PMID:25585933

Launch Commit Criteria Monitoring Agent

NASA Technical Reports Server (NTRS)

Semmel, Glenn S.; Davis, Steven R.; Leucht, Kurt W.; Rowe, Dan A.; Kelly, Andrew O.; Boeloeni, Ladislau

2005-01-01

The Spaceport Processing Systems Branch at NASA Kennedy Space Center has developed and deployed a software agent to monitor the Space Shuttle's ground processing telemetry stream. The application, the Launch Commit Criteria Monitoring Agent, increases situational awareness for system and hardware engineers during Shuttle launch countdown. The agent provides autonomous monitoring of the telemetry stream, automatically alerts system engineers when predefined criteria have been met, identifies limit warnings and violations of launch commit criteria, aids Shuttle engineers through troubleshooting procedures, and provides additional insight to verify appropriate troubleshooting of problems by contractors. The agent has successfully detected launch commit criteria warnings and violations on a simulated playback data stream. Efficiency and safety are improved through increased automation.

A Multiagent-based Intrusion Detection System with the Support of Multi-Class Supervised Classification

NASA Astrophysics Data System (ADS)

Shyu, Mei-Ling; Sainani, Varsha

The increasing number of network security related incidents have made it necessary for the organizations to actively protect their sensitive data with network intrusion detection systems (IDSs). IDSs are expected to analyze a large volume of data while not placing a significantly added load on the monitoring systems and networks. This requires good data mining strategies which take less time and give accurate results. In this study, a novel data mining assisted multiagent-based intrusion detection system (DMAS-IDS) is proposed, particularly with the support of multiclass supervised classification. These agents can detect and take predefined actions against malicious activities, and data mining techniques can help detect them. Our proposed DMAS-IDS shows superior performance compared to central sniffing IDS techniques, and saves network resources compared to other distributed IDS with mobile agents that activate too many sniffers causing bottlenecks in the network. This is one of the major motivations to use a distributed model based on multiagent platform along with a supervised classification technique.

Development of nanostars as a biocompatible tumor contrast agent: toward in vivo SERS imaging.

PubMed

D'Hollander, Antoine; Mathieu, Evelien; Jans, Hilde; Vande Velde, Greetje; Stakenborg, Tim; Van Dorpe, Pol; Himmelreich, Uwe; Lagae, Liesbet

2016-01-01

The need for sensitive imaging techniques to detect tumor cells is an important issue in cancer diagnosis and therapy. Surface-enhanced Raman scattering (SERS), realized by chemisorption of compounds suitable for Raman spectroscopy onto gold nanoparticles, is a new method for detecting a tumor. As a proof of concept, we studied the use of biocompatible gold nanostars as sensitive SERS contrast agents targeting an ovarian cancer cell line (SKOV3). Due to a high intracellular uptake of gold nanostars after 6 hours of exposure, they could be detected and located with SERS. Using these nanostars for passive targeting after systemic injection in a xenograft mouse model, a detectable signal was measured in the tumor and liver in vivo. These signals were confirmed by ex vivo SERS measurements and darkfield microscopy. In this study, we established SERS nanostars as a highly sensitive contrast agent for tumor detection, which opens the potential for their use as a theranostic agent against cancer.

SiC: An Agent Based Architecture for Preventing and Detecting Attacks to Ubiquitous Databases

NASA Astrophysics Data System (ADS)

Pinzón, Cristian; de Paz, Yanira; Bajo, Javier; Abraham, Ajith; Corchado, Juan M.

One of the main attacks to ubiquitous databases is the structure query language (SQL) injection attack, which causes severe damages both in the commercial aspect and in the user’s confidence. This chapter proposes the SiC architecture as a solution to the SQL injection attack problem. This is a hierarchical distributed multiagent architecture, which involves an entirely new approach with respect to existing architectures for the prevention and detection of SQL injections. SiC incorporates a kind of intelligent agent, which integrates a case-based reasoning system. This agent, which is the core of the architecture, allows the application of detection techniques based on anomalies as well as those based on patterns, providing a great degree of autonomy, flexibility, robustness and dynamic scalability. The characteristics of the multiagent system allow an architecture to detect attacks from different types of devices, regardless of the physical location. The architecture has been tested on a medical database, guaranteeing safe access from various devices such as PDAs and notebook computers.

Detection/classification/quantification of chemical agents using an array of surface acoustic wave (SAW) devices

NASA Astrophysics Data System (ADS)

Milner, G. Martin

2005-05-01

ChemSentry is a portable system used to detect, identify, and quantify chemical warfare (CW) agents. Electro chemical (EC) cell sensor technology is used for blood agents and an array of surface acoustic wave (SAW) sensors is used for nerve and blister agents. The combination of the EC cell and the SAW array provides sufficient sensor information to detect, classify and quantify all CW agents of concern using smaller, lighter, lower cost units. Initial development of the SAW array and processing was a key challenge for ChemSentry requiring several years of fundamental testing of polymers and coating methods to finalize the sensor array design in 2001. Following the finalization of the SAW array, nearly three (3) years of intensive testing in both laboratory and field environments were required in order to gather sufficient data to fully understand the response characteristics. Virtually unbounded permutations of agent characteristics and environmental characteristics must be considered in order to operate against all agents and all environments of interest to the U.S. military and other potential users of ChemSentry. The resulting signal processing design matched to this extensive body of measured data (over 8,000 agent challenges and 10,000 hours of ambient data) is considered to be a significant advance in state-of-the-art for CW agent detection.

Optically coded nanocrystal taggants and optical frequency IDs

NASA Astrophysics Data System (ADS)

Williams, George M., Jr.; Allen, Thomas; Dupuy, Charles; Novet, Thomas; Schut, David

2010-04-01

A series of nanocrystal and nanocrystal quantum dot taggant technologies were developed for covertly tagging and tracking objects of interest. Homogeneous and heterogeneous nanocrystal taggant designs were developed and optimized for ultraviolet through infrared emissions, utilizing either Dexter energy transfer or Förster resonant energy transfer (FRET) between specific absorbing and emitting functionalities. The conversion efficiency, target-specific identification, and adhesion properties of the taggants were engineered by means of various surface ligand chemistries. The ability to engineer poly-functional ligands was shown effective in the detection of a biological agent simulant, detected through a NC photoluminescence that is altered in the presence of the agent of interest; the technique has broad potential applicability to chemical, biological, and explosive (CBE) agent detection. The NC photoluminescence can be detected by a remote LIDAR system; the performance of a taggant system has been modeled and subsequently verified in a series of controlled field tests. LIDAR detection of visible-emitting taggants was shown to exceed 2.8 km in calibrated field tests, and from these field data and calibrated laboratory measurements we predict >5 km range in the covert shortwavelength infrared (SWIR) spectral region.

Design and Implementation of Context-Aware Musuem Guide Agents

NASA Astrophysics Data System (ADS)

Satoh, Ichiro

This paper presents an agent-based system for building and operating context-aware services in public spaces, including museums. The system provides users with agents and detects the locations of users and deploys location-aware user-assistant agents at computers near the their current locations by using active RFID-tags. When a visitor moves between exhibits in a museum, this dynamically deploys his/her agent at the computers close to the exhibits by using mobile agent technology. It annotates the exhibits in his/her personalized form and navigate him/her user to the next exhibits along his/her routes. It also introduces user movement as a natural approach to interacting between users and agents. To demonstrate the utility and effectiveness of the system, we constructed location/user-aware visitor-guide services and experimented them for two weeks in a public museum.

Chemiresistor Devices for Chemical Warfare Agent Detection Based on Polymer Wrapped Single-Walled Carbon Nanotubes

PubMed Central

Fennell, John F.; Hamaguchi, Hitoshi; Yoon, Bora; Swager, Timothy M.

2017-01-01

Chemical warfare agents (CWA) continue to present a threat to civilian populations and military personnel in operational areas all over the world. Reliable measurements of CWAs are critical to contamination detection, avoidance, and remediation. The current deployed systems in United States and foreign militaries, as well as those in the private sector offer accurate detection of CWAs, but are still limited by size, portability and fabrication cost. Herein, we report a chemiresistive CWA sensor using single-walled carbon nanotubes (SWCNTs) wrapped with poly(3,4-ethylenedioxythiophene) (PEDOT) derivatives. We demonstrate that a pendant hexafluoroisopropanol group on the polymer that enhances sensitivity to a nerve agent mimic, dimethyl methylphosphonate, in both nitrogen and air environments to concentrations as low as 5 ppm and 11 ppm, respectively. Additionally, these PEDOT/SWCNT derivative sensor systems experience negligible device performance over the course of two weeks under ambient conditions. PMID:28452929

Chemiresistor Devices for Chemical Warfare Agent Detection Based on Polymer Wrapped Single-Walled Carbon Nanotubes.

PubMed

Fennell, John F; Hamaguchi, Hitoshi; Yoon, Bora; Swager, Timothy M

2017-04-28

Chemical warfare agents (CWA) continue to present a threat to civilian populations and military personnel in operational areas all over the world. Reliable measurements of CWAs are critical to contamination detection, avoidance, and remediation. The current deployed systems in United States and foreign militaries, as well as those in the private sector offer accurate detection of CWAs, but are still limited by size, portability and fabrication cost. Herein, we report a chemiresistive CWA sensor using single-walled carbon nanotubes (SWCNTs) wrapped with poly(3,4-ethylenedioxythiophene) (PEDOT) derivatives. We demonstrate that a pendant hexafluoroisopropanol group on the polymer that enhances sensitivity to a nerve agent mimic, dimethyl methylphosphonate, in both nitrogen and air environments to concentrations as low as 5 ppm and 11 ppm, respectively. Additionally, these PEDOT/SWCNT derivative sensor systems experience negligible device performance over the course of two weeks under ambient conditions.

Thin membrane sensor with biochemical switch

NASA Technical Reports Server (NTRS)

Worley, III, Jennings F. (Inventor); Case, George D. (Inventor)

1994-01-01

A modular biosensor system for chemical or biological agent detection utilizes electrochemical measurement of an ion current across a gate membrane triggered by the reaction of the target agent with a recognition protein conjugated to a channel blocker. The sensor system includes a bioresponse simulator or biochemical switch module which contains the recognition protein-channel blocker conjugate, and in which the detection reactions occur, and a transducer module which contains a gate membrane and a measuring electrode, and in which the presence of agent is sensed electrically. In the poised state, ion channels in the gate membrane are blocked by the recognition protein-channel blocker conjugate. Detection reactions remove the recognition protein-channel blocker conjugate from the ion channels, thus eliciting an ion current surge in the gate membrane which subsequently triggers an output alarm. Sufficiently large currents are generated that simple direct current electronics are adequate for the measurements. The biosensor has applications for environmental, medical, and industrial use.

Overview of the joint services lightweight standoff chemical agent detector (JSLSCAD)

NASA Astrophysics Data System (ADS)

Hammond, Barney; Popa, Mirela

2005-05-01

This paper presents a system-level description of the Joint Services Lightweight Standoff Chemical Agent Detector (JSLSCAD). JSLSCAD is a passive Fourier Transform InfraRed (FTIR) based remote sensing system for detecting chemical warfare agents. Unlike predecessor systems, JSLSCAD is capable of operating while on the move to accomplish reconnaissance, surveillance, and contamination avoidance missions. Additionally, the system is designed to meet the needs for application on air and sea as well as ground mobile and fixed site platforms. The core of the system is a rugged Michelson interferometer with a flexure spring bearing mechanism and bi-directional data acquisition capability. The sensor is interfaced to a small, high performance spatial scanner that provides high-speed, two-axis area coverage. Command, control, and processing electronics have been coupled with real time control software and robust detection/discrimination algorithms. Operator interfaces include local and remote options in addition to interfaces to external communications networks. The modular system design facilitates interfacing to the many platforms targeted for JSLSCAD.

Enhanced monitor system for water protection

DOEpatents

Hill, David E [Knoxville, TN; Rodriquez, Jr., Miguel [Oak Ridge, TN; Greenbaum, Elias [Knoxville, TN

2009-09-22

An automatic, self-contained device for detecting toxic agents in a water supply includes an analyzer for detecting at least one toxic agent in a water sample, introducing a means for introducing a water sample into the analyzer and discharging the water sample from the analyzer, holding means for holding a water sample for a pre-selected period of time before the water sample is introduced into the analyzer, and an electronics package that analyzes raw data from the analyzer and emits a signal indicating the presence of at least one toxic agent in the water sample.

Fluorescent discrimination between traces of chemical warfare agents and their mimics.

PubMed

Díaz de Greñu, Borja; Moreno, Daniel; Torroba, Tomás; Berg, Alexander; Gunnars, Johan; Nilsson, Tobias; Nyman, Rasmus; Persson, Milton; Pettersson, Johannes; Eklind, Ida; Wästerby, Pär

2014-03-19

An array of fluorogenic probes is able to discriminate between nerve agents, sarin, soman, tabun, VX and their mimics, in water or organic solvent, by qualitative fluorescence patterns and quantitative multivariate analysis, thus making the system suitable for the in-the-field detection of traces of chemical warfare agents as well as to differentiate between the real nerve agents and other related compounds.

Autonomous microfluidic sample preparation system for protein profile-based detection of aerosolized bacterial cells and spores.

PubMed

Stachowiak, Jeanne C; Shugard, Erin E; Mosier, Bruce P; Renzi, Ronald F; Caton, Pamela F; Ferko, Scott M; Van de Vreugde, James L; Yee, Daniel D; Haroldsen, Brent L; VanderNoot, Victoria A

2007-08-01

For domestic and military security, an autonomous system capable of continuously monitoring for airborne biothreat agents is necessary. At present, no system meets the requirements for size, speed, sensitivity, and selectivity to warn against and lead to the prevention of infection in field settings. We present a fully automated system for the detection of aerosolized bacterial biothreat agents such as Bacillus subtilis (surrogate for Bacillus anthracis) based on protein profiling by chip gel electrophoresis coupled with a microfluidic sample preparation system. Protein profiling has previously been demonstrated to differentiate between bacterial organisms. With the goal of reducing response time, multiple microfluidic component modules, including aerosol collection via a commercially available collector, concentration, thermochemical lysis, size exclusion chromatography, fluorescent labeling, and chip gel electrophoresis were integrated together to create an autonomous collection/sample preparation/analysis system. The cycle time for sample preparation was approximately 5 min, while total cycle time, including chip gel electrophoresis, was approximately 10 min. Sensitivity of the coupled system for the detection of B. subtilis spores was 16 agent-containing particles per liter of air, based on samples that were prepared to simulate those collected by wetted cyclone aerosol collector of approximately 80% efficiency operating for 7 min.

Potential of Pest and Host Phenological Data in the Attribution of Regional Forest Disturbance Detection Maps According to Causal Agent

NASA Technical Reports Server (NTRS)

Spruce, Joseph; Hargrove, William; Norman Steve; Christie, William

2014-01-01

Near real time forest disturbance detection maps from MODIS NDVI phenology data have been produced since 2010 for the conterminous U.S., as part of the on-line ForWarn national forest threat early warning system. The latter has been used by the forest health community to identify and track many regional forest disturbances caused by multiple biotic and abiotic damage agents. Attribution of causal agents for detected disturbances has been a goal since project initiation in 2006. Combined with detailed cover type maps, geospatial pest phenology data offer a potential means for narrowing the candidate causal agents responsible for a given biotic disturbance. U.S. Aerial Detection Surveys (ADS) employ such phenology data. Historic ADS products provide general locational data on recent insect-induced forest type specific disturbances that may help in determining candidate causal agents for MODIS-based disturbance maps, especially when combined with other historic geospatial disturbance data (e.g., wildfire burn scars and drought maps). Historic ADS disturbance detection polygons can show severe and extensive regional forest disturbances, though they also can show polygons with sparsely scattered or infrequent disturbances. Examples will be discussed that use various historic disturbance data to help determine potential causes of MODIS-detected regional forest disturbance anomalies.

Spatiotemporal trends in the discovery of new swine infectious agents.

PubMed

Fournié, Guillaume; Kearsley-Fleet, Lianne; Otte, Joachim; Pfeiffer, Dirk Udo

2015-09-28

A literature review was conducted to assess the spatiotemporal trend and diversity of infectious agents that were newly found in pigs between 1985 and 2010. We identified 173 new variants from 91 species, of which 73 species had not been previously described in pigs. These new species, of which one third was zoonotic, were taxonomically diverse. They were identified throughout the study period, predominantly in the main pork producing countries, with the rate of discovery of new virus variants doubling within the last 10 years of the study period. Whilst infectious agent species newly detected in high-income countries were more likely to be associated with higher virulence, zoonotic agents prevailed in low- and middle-income countries. Although this trend is influenced by factors conditioning infectious agent detection - diagnostic methods, surveillance efforts, research interests -, it may suggest that different scales and types of production systems promote emergence of certain types of infectious agents. Considering the rapid transformation of the swine industry, concerted efforts are needed for improving our understanding of the factors influencing the emergence of infectious agents. This information then needs to inform the design of risk-based surveillance systems and strategies directly mitigating the risk associated with these factors.

Water cooler towers and other man-made aquatic systems as environmental collection systems for agents of concern

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brigmon, Robin; Kingsley, Mark T.

An apparatus and process of using existing process water sources such as cooling towers, fountains, and waterfalls is provided in which the water sources are utilized as monitoring system for the detection of environmental agents which may be present in the environment. The process water is associated with structures and have an inherent filtering or absorbing capability available in the materials and therefore can be used as a rapid screening tool for quality and quantitative assessment of environmental agents.

A Distributed, Collaborative Intelligent Agent System Approach for Proactive Postmarketing Drug Safety Surveillance

PubMed Central

Ji, Yanqing; Ying, Hao; Farber, Margo S.; Yen, John; Dews, Peter; Miller, Richard E.; Massanari, R. Michael

2014-01-01

Discovering unknown adverse drug reactions (ADRs) in postmarketing surveillance as early as possible is of great importance. The current approach to postmarketing surveillance primarily relies on spontaneous reporting. It is a passive surveillance system and limited by gross underreporting (<10% reporting rate), latency, and inconsistent reporting. We propose a novel team-based intelligent agent software system approach for proactively monitoring and detecting potential ADRs of interest using electronic patient records. We designed such a system and named it ADRMonitor. The intelligent agents, operating on computers located in different places, are capable of continuously and autonomously collaborating with each other and assisting the human users (e.g., the food and drug administration (FDA), drug safety professionals, and physicians). The agents should enhance current systems and accelerate early ADR identification. To evaluate the performance of the ADRMonitor with respect to the current spontaneous reporting approach, we conducted simulation experiments on identification of ADR signal pairs (i.e., potential links between drugs and apparent adverse reactions) under various conditions. The experiments involved over 275 000 simulated patients created on the basis of more than 1000 real patients treated by the drug cisapride that was on the market for seven years until its withdrawal by the FDA in 2000 due to serious ADRs. Healthcare professionals utilizing the spontaneous reporting approach and the ADRMonitor were separately simulated by decision-making models derived from a general cognitive decision model called fuzzy recognition-primed decision (RPD) model that we recently developed. The quantitative simulation results show that 1) the number of true ADR signal pairs detected by the ADRMonitor is 6.6 times higher than that by the spontaneous reporting strategy; 2) the ADR detection rate of the ADRMonitor agents with even moderate decision-making skills is five times higher than that of spontaneous reporting; and 3) as the number of patient cases increases, ADRs could be detected significantly earlier by the ADRMonitor. PMID:20007038

Content modification attacks on consensus seeking multi-agent system with double-integrator dynamics.

PubMed

Dong, Yimeng; Gupta, Nirupam; Chopra, Nikhil

2016-11-01

In this paper, vulnerability of a distributed consensus seeking multi-agent system (MAS) with double-integrator dynamics against edge-bound content modification cyber attacks is studied. In particular, we define a specific edge-bound content modification cyber attack called malignant content modification attack (MCoMA), which results in unbounded growth of an appropriately defined group disagreement vector. Properties of MCoMA are utilized to design detection and mitigation algorithms so as to impart resilience in the considered MAS against MCoMA. Additionally, the proposed detection mechanism is extended to detect the general edge-bound content modification attacks (not just MCoMA). Finally, the efficacies of the proposed results are illustrated through numerical simulations.

Content modification attacks on consensus seeking multi-agent system with double-integrator dynamics

NASA Astrophysics Data System (ADS)

Dong, Yimeng; Gupta, Nirupam; Chopra, Nikhil

2016-11-01

In this paper, vulnerability of a distributed consensus seeking multi-agent system (MAS) with double-integrator dynamics against edge-bound content modification cyber attacks is studied. In particular, we define a specific edge-bound content modification cyber attack called malignant content modification attack (MCoMA), which results in unbounded growth of an appropriately defined group disagreement vector. Properties of MCoMA are utilized to design detection and mitigation algorithms so as to impart resilience in the considered MAS against MCoMA. Additionally, the proposed detection mechanism is extended to detect the general edge-bound content modification attacks (not just MCoMA). Finally, the efficacies of the proposed results are illustrated through numerical simulations.

Vibrational spectroscopy standoff detection of threat chemicals

NASA Astrophysics Data System (ADS)

Ortiz-Rivera, William; Pacheco-Londoño, Leonardo C.; Castro-Suarez, John R.; Felix-Rivera, Hilsamar; Hernandez-Rivera, Samuel P.

2011-06-01

Spectroscopy based standoff detection systems: Raman and FTIR have been tested for detection of threat chemicals, including highly energetic materials, homemade explosives, explosives formulations and high explosives mixtures. Other threat chemicals studied included toxic industrial compounds (TIC) and chemical agent simulants. Microorganisms and biological threat agent simulants have also been detected at standoff distances. Open Path FTIR has been used to detect vapors and chemicals deposited on metal surfaces at μg/cm2 levels at distances as far as 30 m in active mode and 60 m in passive mode. In the case of Raman telescope, standoff distances for acetonitrile and ammonium nitrate were 140 m.

A biolayer interferometry-based assay for rapid and highly sensitive detection of biowarfare agents.

PubMed

Mechaly, Adva; Cohen, Hila; Cohen, Ofer; Mazor, Ohad

2016-08-01

Biolayer interferometry (BLI) is an optical technique that uses fiber-optic biosensors for label-free real-time monitoring of protein-protein interactions. In this study, we coupled the advantages of the Octet Red BLI system (automation, fluidics-free, and on-line monitoring) with a signal enhancement step and developed a rapid and sensitive immunological-based method for detection of biowarfare agents. As a proof of concept, we chose to demonstrate the efficacy of this novel assay for the detection of agents representing two classes of biothreats, proteinaceous toxins, and bacterial pathogens: ricin, a lethal plant toxin, and the gram-negative bacterium Francisella tularensis, the causative agent of tularemia. The assay setup consisted of biotinylated antibodies immobilized to the biosensor coupled with alkaline phosphatase-labeled antibodies as the detection moiety to create nonsoluble substrate crystals that precipitate on the sensor surface, thereby inducing a significant wavelength interference. It was found that this BLI-based assay enables sensitive detection of these pathogens (detection limits of 10 pg/ml and 1 × 10(4) pfu/ml ricin and F. tularensis, respectively) within a very short time frame (17 min). Owing to its simplicity, this assay can be easily adapted to detect other analytes in general, and biowarfare agents in particular, in a rapid and sensitive manner. Copyright © 2016 Elsevier Inc. All rights reserved.

Recent Advances in the Development of Chromophore-Based Chemosensors for Nerve Agents and Phosgene.

PubMed

Chen, Liyan; Wu, Di; Yoon, Juyoung

2018-01-26

The extreme toxicity and ready accessibility of nerve agents and phosgene has caused an increase in the demand to develop effective systems for the detection of these substances. Among the traditional platforms utilized for this purpose, chemosensors including surface acoustic wave (SAW) sensors, enzymes, carbon nanotubes, nanoparticles, and chromophore based sensors have attracted increasing attention. In this review, we describe in a comprehensive manner recent progress that has been made on the development of chromophore-based chemosensors for detecting nerve agents (mimic) and phosgene. This review comprises two sections focusing on studies of the development of chemosensors for nerve agents (mimic) and phosgene. In each of the sections, the discussion follows a format which concentrates on different reaction sites/mechanisms involved in the sensing processes. Finally, chemosensors uncovered in these efforts are compared with those based on other sensing methods and challenges facing the design of more effective chemosensors for the detection of nerve agents (mimic) and phosgene are discussed.

A highly stable minimally processed plant-derived recombinant acetylcholinesterase for nerve agent detection in adverse conditions

PubMed Central

Rosenberg, Yvonne J.; Walker, Jeremy; Jiang, Xiaoming; Donahue, Scott; Robosky, Jason; Sack, Markus; Lees, Jonathan; Urban, Lori

2015-01-01

Although recent innovations in transient plant systems have enabled gram quantities of proteins in 1–2 weeks, very few have been translated into applications due to technical challenges and high downstream processing costs. Here we report high-level production, using a Nicotiana benthamiana/p19 system, of an engineered recombinant human acetylcholinesterase (rAChE) that is highly stable in a minimally processed leaf extract. Lyophylized clarified extracts withstand prolonged storage at 70 °C and, upon reconstitution, can be used in several devices to detect organophosphate (OP) nerve agents and pesticides on surfaces ranging from 0 °C to 50 °C. The recent use of sarin in Syria highlights the urgent need for nerve agent detection and countermeasures necessary for preparedness and emergency responses. Bypassing cumbersome and expensive downstream processes has enabled us to fully exploit the speed, low cost and scalability of transient production systems resulting in the first successful implementation of plant-produced rAChE into a commercial biotechnology product. PMID:26268538

A highly stable minimally processed plant-derived recombinant acetylcholinesterase for nerve agent detection in adverse conditions.

PubMed

Rosenberg, Yvonne J; Walker, Jeremy; Jiang, Xiaoming; Donahue, Scott; Robosky, Jason; Sack, Markus; Lees, Jonathan; Urban, Lori

2015-08-13

Although recent innovations in transient plant systems have enabled gram quantities of proteins in 1-2 weeks, very few have been translated into applications due to technical challenges and high downstream processing costs. Here we report high-level production, using a Nicotiana benthamiana/p19 system, of an engineered recombinant human acetylcholinesterase (rAChE) that is highly stable in a minimally processed leaf extract. Lyophylized clarified extracts withstand prolonged storage at 70 °C and, upon reconstitution, can be used in several devices to detect organophosphate (OP) nerve agents and pesticides on surfaces ranging from 0 °C to 50 °C. The recent use of sarin in Syria highlights the urgent need for nerve agent detection and countermeasures necessary for preparedness and emergency responses. Bypassing cumbersome and expensive downstream processes has enabled us to fully exploit the speed, low cost and scalability of transient production systems resulting in the first successful implementation of plant-produced rAChE into a commercial biotechnology product.

Ultraviolet Raman scattering from persistent chemical warfare agents

NASA Astrophysics Data System (ADS)

Kullander, Fredrik; Wästerby, Pär.; Landström, Lars

2016-05-01

Laser induced Raman scattering at excitation wavelengths in the middle ultraviolet was examined using a pulsed tunable laser based spectrometer system. Droplets of chemical warfare agents, with a volume of 2 μl, were placed on a silicon surface and irradiated with sequences of laser pulses. The Raman scattering from V-series nerve agents, Tabun (GA) and Mustard gas (HD) was studied with the aim of finding the optimum parameters and the requirements for a detection system. A particular emphasis was put on V-agents that have been previously shown to yield relatively weak Raman scattering in this excitation band.

Solid-phase microextraction coupled to gas chromatography for the determination of 2,3-dimethyl-2,3-dinitrobutane as a marking agent for explosives.

PubMed

Li, Xiujuan; Zeng, Zhaorui; Zeng, Yi

2007-06-15

This paper investigates the detection of 2,3-dimethyl-2,3-dinitrobutane (DMNB), a marking agent in explosives, by gas chromatography (GC) with electron capture detection using solid-phase microextraction (SPME) as a sample preparation technique. The 25,27-dihydroxy-26,28-oxy (2',7'-dioxo-3',6'-diazaoctyl) oxy-p-tert-butylcalix[4]arene/hydroxy-terminated silicone oil coated fiber was highly sensitive to trap DMNB from ammonium nitrate matrix. The analysis was performed by extracting 2g of explosives for 30s at room temperature and then immediately introducing into the heated GC injector for 1min of thermal desorption. The method showed good linearity in the range from 0.01 to 1.0mug/g. The relative standard deviations for these extractions were <8%. The calculated limit of detection for DMNB (S/N=3) was 4.43x10(-4)mug/g, which illustrates that the proposed systems are suitable for explosive detection at trace level. This is the first report of an SPME-GC system shown to extract marking agent in explosives for subsequent detection in a simple, rapid, sensitive, and inexpensive manner.

Single-particle aerosol mass spectrometry for the detection and identification of chemical warfare agent simulants.

PubMed

Martin, Audrey N; Farquar, George R; Frank, Matthias; Gard, Eric E; Fergenson, David P

2007-08-15

Single-particle aerosol mass spectrometry (SPAMS) was used for the real-time detection of liquid nerve agent simulants. A total of 1000 dual-polarity time-of-flight mass spectra were obtained for micrometer-sized single particles each of dimethyl methyl phosphonate, diethyl ethyl phosphonate, diethyl phosphoramidate, and diethyl phthalate using laser fluences between 0.58 and 7.83 nJ/microm2, and mass spectral variation with laser fluence was studied. The mass spectra obtained allowed identification of single particles of the chemical warfare agent (CWA) simulants at each laser fluence used although lower laser fluences allowed more facile identification. SPAMS is presented as a promising real-time detection system for the presence of CWAs.

MFIRE-2: A Multi Agent System for Flow-Based Intrusion Detection Using Stochastic Search

DTIC Science & Technology

2012-03-01

attacks that are distributed in nature , but may not protect individual systems effectively without incurring large bandwidth penalties while collecting...system-level information to help prepare for more significant attacks. The type of information potentially revealed by footprinting includes account...key areas where MAS may be appropriate: • The environment is open, highly dynamic, uncertain, or complex • Agents are a natural metaphor—Many

Organization of the secure distributed computing based on multi-agent system

NASA Astrophysics Data System (ADS)

Khovanskov, Sergey; Rumyantsev, Konstantin; Khovanskova, Vera

2018-04-01

Nowadays developing methods for distributed computing is received much attention. One of the methods of distributed computing is using of multi-agent systems. The organization of distributed computing based on the conventional network computers can experience security threats performed by computational processes. Authors have developed the unified agent algorithm of control system of computing network nodes operation. Network PCs is used as computing nodes. The proposed multi-agent control system for the implementation of distributed computing allows in a short time to organize using of the processing power of computers any existing network to solve large-task by creating a distributed computing. Agents based on a computer network can: configure a distributed computing system; to distribute the computational load among computers operated agents; perform optimization distributed computing system according to the computing power of computers on the network. The number of computers connected to the network can be increased by connecting computers to the new computer system, which leads to an increase in overall processing power. Adding multi-agent system in the central agent increases the security of distributed computing. This organization of the distributed computing system reduces the problem solving time and increase fault tolerance (vitality) of computing processes in a changing computing environment (dynamic change of the number of computers on the network). Developed a multi-agent system detects cases of falsification of the results of a distributed system, which may lead to wrong decisions. In addition, the system checks and corrects wrong results.

Chemical-Sensing Cables Detect Potential Threats

NASA Technical Reports Server (NTRS)

2007-01-01

Intelligent Optical Systems Inc. (IOS) completed Phase I and II Small Business Innovation Research (SBIR) contracts with NASA's Langley Research Center to develop moisture- and pH-sensitive sensors to detect corrosion or pre-corrosive conditions, warning of potentially dangerous conditions before significant structural damage occurs. This new type of sensor uses a specially manufactured optical fiber whose entire length is chemically sensitive, changing color in response to contact with its target, and demonstrated to detect potentially corrosive moisture incursions to within 2 cm. After completing the work with NASA, the company received a Defense Advanced Research Projects Agency (DARPA) Phase III SBIR to develop the sensors further for detecting chemical warfare agents, for which they proved just as successful. The company then worked with the U.S. Department of Defense (DoD) to fine tune the sensors for detecting potential threats, such as toxic industrial compounds and nerve agents. In addition to the work with government agencies, Intelligent Optical Systems has sold the chemically sensitive fiber optic cables to major automotive and aerospace companies, who are finding a variety of uses for the devices. Marketed under the brand name Distributed Intrinsic Chemical Agent Sensing and Transmission (DICAST), these unique continuous-cable fiber optic chemical sensors can serve in a variety of applications: Corrosive-condition monitoring, aiding experimentation with nontraditional power sources, as an economical means of detecting chemical release in large facilities, as an inexpensive "alarm" systems to alert the user to a change in the chemical environment anywhere along the cable, or in distance-resolved optical time domain reflectometry systems to provide detailed profiles of chemical concentration versus length.

Fluorescent sensors for the detection of chemical warfare agents.

PubMed

Burnworth, Mark; Rowan, Stuart J; Weder, Christoph

2007-01-01

Along with biological and nuclear threats, chemical warfare agents are some of the most feared weapons of mass destruction. Compared to nuclear weapons they are relatively easy to access and deploy, which makes them in some aspects a greater threat to national and global security. A particularly hazardous class of chemical warfare agents are the nerve agents. Their rapid and severe effects on human health originate in their ability to block the function of acetylcholinesterase, an enzyme that is vital to the central nervous system. This article outlines recent activities regarding the development of molecular sensors that can visualize the presence of nerve agents (and related pesticides) through changes of their fluorescence properties. Three different sensing principles are discussed: enzyme-based sensors, chemically reactive sensors, and supramolecular sensors. Typical examples are presented for each class and different fluorescent sensors for the detection of chemical warfare agents are summarized and compared.

Adaptation of a military FTS to civilian air toxics measurements

DOE Office of Scientific and Technical Information (OSTI.GOV)

Engel, J.R.; Dorval, R.K.

1994-12-31

In many ways, the military problem of chemical agent detection is similar to the civilian problem of toxic and related air pollutants detection. A recent program to design a next generation Fourier transform spectrometer (FTS) based chemical agent detection system has been funded by the US Army. This program has resulted in an FTS system that has a number of characteristics that make it suitable for applications to the civilian measurement problem. Low power, low weight, and small size lead to low installation, operating and maintenance costs. Innovative use of diode lasers in place of HeNe reference sources leads tomore » long lifetimes and high reliability. Absolute scan position servos allow for highly efficient offset scanning. This paper will relate the performance of this system to present air monitoring requirements.« less

An Artificially Intelligent Physical Model-Checking Approach to Detect Switching-Related Attacks on Power Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

El Hariri, Mohamad; Faddel, Samy; Mohammed, Osama

Decentralized and hierarchical microgrid control strategies have lain the groundwork for shaping the future smart grid. Such control approaches require the cooperation between microgrid operators in control centers, intelligent microcontrollers, and remote terminal units via secure and reliable communication networks. In order to enhance the security and complement the work of network intrusion detection systems, this paper presents an artificially intelligent physical model-checking that detects tampered-with circuit breaker switching control commands whether, due to a cyber-attack or human error. In this technique, distributed agents, which are monitoring sectionalized areas of a given microgrid, will be trained and continuously adapted tomore » verify that incoming control commands do not violate the physical system operational standards and do not put the microgrid in an insecure state. The potential of this approach has been tested by deploying agents that monitor circuit breakers status commands on a 14-bus IEEE benchmark system. The results showed the accuracy of the proposed framework in characterizing the power system and successfully detecting malicious and/or erroneous control commands.« less

Pervasive surveillance-agent system based on wireless sensor networks: design and deployment

NASA Astrophysics Data System (ADS)

Martínez, José F.; Bravo, Sury; García, Ana B.; Corredor, Iván; Familiar, Miguel S.; López, Lourdes; Hernández, Vicente; Da Silva, Antonio

2010-12-01

Nowadays, proliferation of embedded systems is enhancing the possibilities of gathering information by using wireless sensor networks (WSNs). Flexibility and ease of installation make these kinds of pervasive networks suitable for security and surveillance environments. Moreover, the risk for humans to be exposed to these functions is minimized when using these networks. In this paper, a virtual perimeter surveillance agent, which has been designed to detect any person crossing an invisible barrier around a marked perimeter and send an alarm notification to the security staff, is presented. This agent works in a state of 'low power consumption' until there is a crossing on the perimeter. In our approach, the 'intelligence' of the agent has been distributed by using mobile nodes in order to discern the cause of the event of presence. This feature contributes to saving both processing resources and power consumption since the required code that detects presence is the only system installed. The research work described in this paper illustrates our experience in the development of a surveillance system using WNSs for a practical application as well as its evaluation in real-world deployments. This mechanism plays an important role in providing confidence in ensuring safety to our environment.

ARO in Review 2010

DTIC Science & Technology

2010-01-01

develop a fundamental understanding of the key recognition elements in various nerve agents , pesticides , and simulants. Using this knowledge, these groups...SCIENCES DIVISION 29 ARO IN REVIEW 2010 1. Low-power Nerve Agent Detector. Three Phase I CBD-SBIR contracts were awarded to Identizyme Defense...Technologies, Inc., Luna Innovations, Inc., and Lynntech, Inc. to develop a nerve agent detection system that requires little to no operating power

Detection of vulnerable neurons damaged by environmental insults in utero

PubMed Central

Torii, Masaaki; Chang, Yu-Wen; Ishii, Seiji; Waxman, Stephen G.; Kocsis, Jeffery D.; Rakic, Pasko; Hashimoto-Torii, Kazue

2017-01-01

Development of prognostic biomarkers for the detection of prenatally damaged neurons before manifestations of postnatal disorders is an essential step for prevention and treatment of susceptible individuals. We have developed a versatile fluorescence reporter system in mice enabling detection of Heat Shock Factor 1 activation in response to prenatal cellular damage caused by exposure to various harmful chemical or physical agents. Using an intrautero electroporation-mediated reporter assay and transgenic reporter mice, we are able to identify neurons that survive prenatal exposure to harmful agents but remain vulnerable in postnatal life. This system may provide a powerful tool for exploring the pathogenesis and treatment of multiple disorders caused by exposure to environmental stress before symptoms become manifested, exacerbated, and/or irreversible. PMID:28123061

Resilient distributed control in the presence of misbehaving agents in networked control systems.

PubMed

Zeng, Wente; Chow, Mo-Yuen

2014-11-01

In this paper, we study the problem of reaching a consensus among all the agents in the networked control systems (NCS) in the presence of misbehaving agents. A reputation-based resilient distributed control algorithm is first proposed for the leader-follower consensus network. The proposed algorithm embeds a resilience mechanism that includes four phases (detection, mitigation, identification, and update), into the control process in a distributed manner. At each phase, every agent only uses local and one-hop neighbors' information to identify and isolate the misbehaving agents, and even compensate their effect on the system. We then extend the proposed algorithm to the leaderless consensus network by introducing and adding two recovery schemes (rollback and excitation recovery) into the current framework to guarantee the accurate convergence of the well-behaving agents in NCS. The effectiveness of the proposed method is demonstrated through case studies in multirobot formation control and wireless sensor networks.

Synergy of irofulven in combination with other DNA damaging agents: synergistic interaction with altretamine, alkylating, and platinum-derived agents in the MV522 lung tumor model.

PubMed

Kelner, Michael J; McMorris, Trevor C; Rojas, Rafael J; Estes, Leita A; Suthipinijtham, Pharnuk

2008-12-01

Irofulven (MGI 114, NSC 683863) is a semisynthetic derivative of illudin S, a natural product present in the Omphalotus illudins (Jack O'Lantern) mushroom. This novel agent produces DNA damage, that in contrast to other agents, is predominately ignored by the global genome repair pathway of the nucleotide excision repair (NER)(2) system. The aim of this study was to determine the antitumor activity of irofulven when administered in combination with 44 different DNA damaging agents, whose damage is in general detected and repaired by the genome repair pathway. The human lung carcinoma MV522 cell line and its corresponding xenograft model were used to evaluate the activity of irofulven in combination with different DNA damaging agents. Two main classes of DNA damaging agents, platinum-derived agents, and select bifunctional alkylating agents, demonstrated in vivo synergistic or super-additive interaction with irofulven. DNA helicase inhibiting agents also demonstrated synergy in vitro, but an enhanced interaction with irofulven could not be demonstrated in vivo. There was no detectable synergistic activity between irofulven and agents capable of inducing DNA cleavage or intercalating into DNA. These results indicate that the antitumor activity of irofulven is enhanced when combined with platinum-derived agents, altretamine, and select alkylating agents such as melphalan or chlorambucil. A common factor between these agents appears to be the production of intrastrand DNA crosslinks. The synergistic interaction between irofulven and other agents may stem from the nucleotide excision repair system being selectively overwhelmed at two distinct points in the pathway, resulting in prolonged stalling of transcription forks, and subsequent initiation of apoptosis.

Microcantilever technology for law enforcement and anti-terrorism applications: chemical, biological, and explosive material detection

NASA Astrophysics Data System (ADS)

Adams, J. D.; Rogers, B.; Whitten, R.

2005-05-01

The remarkable sensitivity, compactness, low cost, low power-consumption, scalability, and versatility of microcantilever sensors make this technology among the most promising solutions for detection of chemical and biological agents, as well as explosives. The University of Nevada, Reno, and Nevada Nanotech Systems, Inc (NNTS) are currently developing a microcantilever-based detection system that will measure trace concentrations of explosives, toxic chemicals, and biological agents in air. A baseline sensor unit design that includes the sensor array, electronics, power supply and air handling has been created and preliminary demonstrations of the microcantilever platform have been conducted. The envisioned device would measure about two cubic inches, run on a small watch battery and cost a few hundred dollars. The device could be operated by untrained law enforcement personnel. Microcantilever-based devices could be used to "sniff out" illegal and/or hazardous chemical and biological agents in high traffic public areas, or be packaged as a compact, low-power system used to monitor cargo in shipping containers. Among the best detectors for such applications at present is the dog, an animal which is expensive, requires significant training and can only be made to work for limited time periods. The public is already accustomed to explosives and metal detection systems in airports and other public venues, making the integration of the proposed device into such security protocols straightforward.

Development of a HIV-1 Virus Detection System Based on Nanotechnology.

PubMed

Lee, Jin-Ho; Oh, Byung-Keun; Choi, Jeong-Woo

2015-04-27

Development of a sensitive and selective detection system for pathogenic viral agents is essential for medical healthcare from diagnostics to therapeutics. However, conventional detection systems are time consuming, resource-intensive and tedious to perform. Hence, the demand for sensitive and selective detection system for virus are highly increasing. To attain this aim, different aspects and techniques have been applied to develop virus sensor with improved sensitivity and selectivity. Here, among those aspects and techniques, this article reviews HIV virus particle detection systems incorporated with nanotechnology to enhance the sensitivity. This review mainly focused on four different detection system including vertically configured electrical detection based on scanning tunneling microscopy (STM), electrochemical detection based on direct electron transfer in virus, optical detection system based on localized surface plasmon resonance (LSPR) and surface enhanced Raman spectroscopy (SERS) using plasmonic nanoparticle.

On the use of multi-agent systems for the monitoring of industrial systems

NASA Astrophysics Data System (ADS)

Rezki, Nafissa; Kazar, Okba; Mouss, Leila Hayet; Kahloul, Laid; Rezki, Djamil

2016-03-01

The objective of the current paper is to present an intelligent system for complex process monitoring, based on artificial intelligence technologies. This system aims to realize with success all the complex process monitoring tasks that are: detection, diagnosis, identification and reconfiguration. For this purpose, the development of a multi-agent system that combines multiple intelligences such as: multivariate control charts, neural networks, Bayesian networks and expert systems has became a necessity. The proposed system is evaluated in the monitoring of the complex process Tennessee Eastman process.

The influence of active vision on the exoskeleton of intelligent agents

NASA Astrophysics Data System (ADS)

Smith, Patrice; Terry, Theodore B.

2016-04-01

Chameleonization occurs when a self-learning autonomous mobile system's (SLAMR) active vision scans the surface of which it is perched causing the exoskeleton to changes colors exhibiting a chameleon effect. Intelligent agents having the ability to adapt to their environment and exhibit key survivability characteristics of its environments would largely be due in part to the use of active vision. Active vision would allow the intelligent agent to scan its environment and adapt as needed in order to avoid detection. The SLAMR system would have an exoskeleton, which would change, based on the surface it was perched on; this is known as the "chameleon effect." Not in the common sense of the term, but from the techno-bio inspired meaning as addressed in our previous paper. Active vision, utilizing stereoscopic color sensing functionality would enable the intelligent agent to scan an object within its close proximity, determine the color scheme, and match it; allowing the agent to blend with its environment. Through the use of its' optical capabilities, the SLAMR system would be able to further determine its position, taking into account spatial and temporal correlation and spatial frequency content of neighboring structures further ensuring successful background blending. The complex visual tasks of identifying objects, using edge detection, image filtering, and feature extraction are essential for an intelligent agent to gain additional knowledge about its environmental surroundings.

Effect of Reduction of Redox Modifications of Cys-Residues in the Na,K-ATPase α1-Subunit on Its Activity

PubMed Central

Dergousova, Elena A.; Petrushanko, Irina Yu.; Klimanova, Elizaveta A.; Mitkevich, Vladimir A.; Ziganshin, Rustam H.; Lopina, Olga D.; Makarov, Alexander A.

2017-01-01

Sodium-potassium adenosine triphosphatase (Na,K-ATPase) creates a gradient of sodium and potassium ions necessary for the viability of animal cells, and it is extremely sensitive to intracellular redox status. Earlier we found that regulatory glutathionylation determines Na,K-ATPase redox sensitivity but the role of basal glutathionylation and other redox modifications of cysteine residues is not clear. The purpose of this study was to detect oxidized, nitrosylated, or glutathionylated cysteine residues in Na,K-ATPase, evaluate the possibility of removing these modifications and assess their influence on the enzyme activity. To this aim, we have detected such modifications in the Na,K-ATPase α1-subunit purified from duck salt glands and tried to eliminate them by chemical reducing agents and the glutaredoxin1/glutathione reductase enzyme system. Detection of cysteine modifications was performed using mass spectrometry and Western blot analysis. We have found that purified Na,K-ATPase α1-subunit contains glutathionylated, nitrosylated, and oxidized cysteines. Chemical reducing agents partially eliminate these modifications that leads to the slight increase of the enzyme activity. Enzyme system glutaredoxin/glutathione reductase, unlike chemical reducing agents, produces significant increase of the enzyme activity. At the same time, the enzyme system deglutathionylates native Na,K-ATPase to a lesser degree than chemical reducing agents. This suggests that the enzymatic reducing system glutaredoxin/glutathione reductase specifically affects glutathionylation of the regulatory cysteine residues of Na,K-ATPase α1-subunit. PMID:28230807

Passive microlesion detection and mapping for treatment of hypertrophic cardiomyopathy

NASA Astrophysics Data System (ADS)

Zhu, Yiying I.; Miller, Douglas L.; Dou, Chunyan; Kripfgans, Oliver D.

2017-03-01

Intermittent high intensity ultrasound pulses with circulating contrast agent microbubbles can induce scattered microlesions of potential value for myocardial reduction therapy. This paper presents an in vitro setup imitating the treatment for monitoring development. A preclinical imaging system with a single element transducer, synchronization and receive-only imaging transducer array has been implemented on a research platform. Contrast agent microbubbles pumped in a dialysis tubing setup were exposed to high intensity focused ultrasound at 1.0/3.5 MHz center frequencies. Polystyrene spheres were employed as linear scatterers compared to contrast agents for system transfer function equalization. A cavitation mapping technique was employed to spatially locate and depict microbubble activity during treatment. For high acoustic pressure amplitudes a 5 dB difference between contrast agent and solid spheres was observed and spatially mapped. The in-plane resolution was 4.5 mm for axial and 1.5 mm laterally. In the future, this cavitation detection scheme will be applied to monitor in vivo microlesioning in real-time.

Unmanned Aerial Vehicle Non Line of Sight Chemical Detection Final Report

DTIC Science & Technology

2016-12-01

aircraft system that is used to perform point detection of chemical warfare agents and collection of vapor, liquid, and solid samples. A modular payload...Standoff Quadcopter Unmanned aircraft system Modular payload 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18. NUMBER OF...Manufacturing Division, modular payloads are being developed to perform point detection and CBRNE sampling. The available UAS is a quadcopter capable of

Hand-held analyser based on microchip electrophoresis with contactless conductivity detection for measurement of chemical warfare agent degradation products

NASA Astrophysics Data System (ADS)

Duran, Karolina-Petkovic; Zhu, Yonggang; Chen, Chuanpin; Swallow, Anthony; Stewart, Robert; Hoobin, Pam; Leech, Patrick; Ovenden, Simon

2008-12-01

This paper reports on the development of a hand-held device for on-site detection of organophosphonate nerve agent degradation products. This field-deployable analyzer relies on efficient microchip electrophoresis separation of alkyl methylphosphonic acids and their sensitive contactless conductivity detection. Miniaturized, low-powered design is coupled with promising analytical performance for separating the breakdown products of chemical warfare agents such as Soman, Sarin and VX . The detector has a detection limit of about 10 μg/mL and has a good linear response in the range 10-300 μg/mL concentration range. Applicability to environmental samples is demonstrated .The new hand-held analyzer offers great promise for converting conventional ion chromatography or capillary electrophoresis sophisticated systems into a portable forensic laboratory for faster, simpler and more reliable on-site screening.

Chemical and biological threat-agent detection using electrophoresis-based lab-on-a-chip devices.

PubMed

Borowsky, Joseph; Collins, Greg E

2007-10-01

The ability to separate complex mixtures of analytes has made capillary electrophoresis (CE) a powerful analytical tool since its modern configuration was first introduced over 25 years ago. The technique found new utility with its application to the microfluidics based lab-on-a-chip platform (i.e., microchip), which resulted in ever smaller footprints, sample volumes, and analysis times. These features, coupled with the technique's potential for portability, have prompted recent interest in the development of novel analyzers for chemical and biological threat agents. This article will comment on three main areas of microchip CE as applied to the separation and detection of threat agents: detection techniques and their corresponding limits of detection, sampling protocol and preparation time, and system portability. These three areas typify the broad utility of lab-on-a-chip for meeting critical, present-day security, in addition to illustrating areas wherein advances are necessary.

Robust Structural Analysis and Design of Distributed Control Systems to Prevent Zero Dynamics Attacks

DOE Office of Scientific and Technical Information (OSTI.GOV)

Weerakkody, Sean; Liu, Xiaofei; Sinopoli, Bruno

We consider the design and analysis of robust distributed control systems (DCSs) to ensure the detection of integrity attacks. DCSs are often managed by independent agents and are implemented using a diverse set of sensors and controllers. However, the heterogeneous nature of DCSs along with their scale leave such systems vulnerable to adversarial behavior. To mitigate this reality, we provide tools that allow operators to prevent zero dynamics attacks when as many as p agents and sensors are corrupted. Such a design ensures attack detectability in deterministic systems while removing the threat of a class of stealthy attacks in stochasticmore » systems. To achieve this goal, we use graph theory to obtain necessary and sufficient conditions for the presence of zero dynamics attacks in terms of the structural interactions between agents and sensors. We then formulate and solve optimization problems which minimize communication networks while also ensuring a resource limited adversary cannot perform a zero dynamics attacks. Polynomial time algorithms for design and analysis are provided.« less

Surface-enhanced Raman spectroscopy of half-mustard agent.

PubMed

Stuart, Douglas A; Biggs, Kevin B; Van Duyne, Richard P

2006-04-01

The detection and identification of chemical warfare agents is an important analytical goal. Herein, it is demonstrated that 2-chloroethyl ethyl sulfide (half-mustard, CEES) can be successfully analysed using surface-enhanced Raman spectroscopy (SERS). A critical component in this detection system is the fabrication of a robust, yet highly enhancing, sensor surface. Recent advances in substrate fabrication and in the fundamental understanding of the SERS phenomenon enable the development of improved substrates for practical SERS applications.

Considerations in detecting CDC select agents under field conditions

NASA Astrophysics Data System (ADS)

Spinelli, Charles; Soelberg, Scott; Swanson, Nathaneal; Furlong, Clement; Baker, Paul

2008-04-01

Surface Plasmon Resonance (SPR) has become a widely accepted technique for real-time detection of interactions between receptor molecules and ligands. Antibody may serve as receptor and can be attached to the gold surface of the SPR device, while candidate analyte fluids contact the detecting antibody. Minute, but detectable, changes in refractive indices (RI) indicate that analyte has bound to the antibody. A decade ago, an inexpensive, robust, miniature and fully integrated SPR chip, called SPREETA, was developed. University of Washington (UW) researchers subsequently developed a portable, temperature-regulated instrument, called SPIRIT, to simultaneously use eight of these three-channel SPREETA chips. A SPIRIT prototype instrument was tested in the field, coupled to a remote reporting system on a surrogate unmanned aerial vehicle (UAV). Two target protein analytes were released sequentially as aerosols with low analyte concentration during each of three flights and were successfully detected and verified. Laboratory experimentation with a more advanced SPIRIT instrument demonstrated detection of very low levels of several select biological agents that might be employed by bioterrorists. Agent detection under field-like conditions is more challenging, especially as analyte concentrations are reduced and complex matricies are introduced. Two different sample preconditioning protocols have been developed for select agents in complex matrices. Use of these preconditioning techniques has allowed laboratory detection in spiked heavy mud of Francisella tularensis at 10 3 CFU/ml, Bacillus anthracis spores at 10 3 CFU/ml, Staphylococcal enterotoxin B (SEB) at 1 ng/ml, and Vaccinia virus (a smallpox simulant) at 10 5 PFU/ml. Ongoing experiments are aimed at simultaneous detection of multiple agents in spiked heavy mud, using a multiplex preconditioning protocol.

Free-surface microfluidics for detection of airborne explosives

NASA Astrophysics Data System (ADS)

Meinhart, Carl; Piorek, Brian; Banerjee, Sanjoy; Lee, Seung Joon; Moskovits, Martin

2008-11-01

A novel microfluidic, remote-sensing, chemical detection platform has been developed for real-time sensing of airborne agents. The key enabling technology is a newly developed concept termed Free-Surface Fluidics (FSF), where one or more fluidic surfaces of a microchannel flow are confined by surface tension and exposed to the surrounding atmosphere. The result is a unique open channel flow environment that is driven by pressure through surface tension, and not subject to body forces, such as gravity. Evaporation and flow rates are controlled by microchannel geometry, surface chemistry and precisely-controlled temperature profiles. The free-surface fluidic architecture is combined with Surface-Enhanced Raman Spectroscopy (SERS) to allow for real-time profiling of atmospheric species and detection of airborne agents. The aggregation of SERS nanoparticles is controlled using microfluidics, to obtain dimer nanoparticle clusters at known streamwise positions in the microchannel. These dimers form SERS hot-spots, which amplify the Raman signal by 8 -- 10 orders of magnitude. Results indicate that explosive agents such as DNT, TNT, RDX, TATP and picric acid in the surrounding atmosphere can be readily detected by the SERS system. Due to the amplification of the SERS system, explosive molecules with concentrations of parts per trillion can be detected, even in the presence of interferent molecules having six orders of magnitude higher concentration.

Advances in Magnetic Resonance Imaging Contrast Agents for Biomarker Detection

PubMed Central

Sinharay, Sanhita; Pagel, Mark D.

2016-01-01

Recent advances in magnetic resonance imaging (MRI) contrast agents have provided new capabilities for biomarker detection through molecular imaging. MRI contrast agents based on the T2 exchange mechanism have more recently expanded the armamentarium of agents for molecular imaging. Compared with T1 and T2* agents, T2 exchange agents have a slower chemical exchange rate, which improves the ability to design these MRI contrast agents with greater specificity for detecting the intended biomarker. MRI contrast agents that are detected through chemical exchange saturation transfer (CEST) have even slower chemical exchange rates. Another emerging class of MRI contrast agents uses hyperpolarized 13C to detect the agent with outstanding sensitivity. These hyperpolarized 13C agents can be used to track metabolism and monitor characteristics of the tissue microenvironment. Together, these various MRI contrast agents provide excellent opportunities to develop molecular imaging for biomarker detection. PMID:27049630

Distributed event-triggered consensus tracking of second-order multi-agent systems with a virtual leader

NASA Astrophysics Data System (ADS)

Jie, Cao; Zhi-Hai, Wu; Li, Peng

2016-05-01

This paper investigates the consensus tracking problems of second-order multi-agent systems with a virtual leader via event-triggered control. A novel distributed event-triggered transmission scheme is proposed, which is intermittently examined at constant sampling instants. Only partial neighbor information and local measurements are required for event detection. Then the corresponding event-triggered consensus tracking protocol is presented to guarantee second-order multi-agent systems to achieve consensus tracking. Numerical simulations are given to illustrate the effectiveness of the proposed strategy. Project supported by the National Natural Science Foundation of China (Grant Nos. 61203147, 61374047, and 61403168).

Method and apparatus for enhanced detection of toxic agents

DOEpatents

Greenbaum, Elias; Rodriguez, Jr., Miguel; Wu, Jie Jayne; Qi, Hairong

2013-10-01

A biosensor based detection of toxins includes enhancing a fluorescence signal by concentrating a plurality of photosynthetic organisms in a fluid into a concentrated region using biased AC electro-osmosis. A measured photosynthetic activity of the photosynthetic organisms is obtained in the concentrated region, where chemical, biological or radiological agents reduce a nominal photosynthetic activity of the photosynthetic organisms. A presence of the chemical, biological and/or radiological agents or precursors thereof, is determined in the fluid based on the measured photosynthetic activity of the concentrated plurality of photosynthetic organisms. A lab-on-a-chip system is used for the concentrating step. The presence of agents is determined from feature vectors, obtained from processing a time dependent signal using amplitude statistics and/or time-frequency analysis, relative to a control signal. A linear discriminant method including support vector machine classification (SVM) is used to identify the agents.

Electrostatic thin film chemical and biological sensor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Prelas, Mark A.; Ghosh, Tushar K.; Tompson, Jr., Robert V.

A chemical and biological agent sensor includes an electrostatic thin film supported by a substrate. The film includes an electrostatic charged surface to attract predetermined biological and chemical agents of interest. A charge collector associated with said electrostatic thin film collects charge associated with surface defects in the electrostatic film induced by the predetermined biological and chemical agents of interest. A preferred sensing system includes a charge based deep level transient spectroscopy system to read out charges from the film and match responses to data sets regarding the agents of interest. A method for sensing biological and chemical agents includesmore » providing a thin sensing film having a predetermined electrostatic charge. The film is exposed to an environment suspected of containing the biological and chemical agents. Quantum surface effects on the film are measured. Biological and/or chemical agents can be detected, identified and quantified based on the measured quantum surface effects.« less

Imbalance detection in a manufacturing system: An agent-based model usage

NASA Astrophysics Data System (ADS)

Shevchuk, G. K.; Zvereva, O. M.; Medvedev, M. A.

2017-11-01

This paper delivers the results of the research work targeted at communications in a manufacturing system. A computer agent-based model which simulates manufacturing system functioning has been engineered. The system lifecycle consists of two recursively repeated stages: a communication stage and a production stage. Model data sets were estimated with the static Leontief's equilibrium equation usage. In experiments relationships between the manufacturing system lifecycle time and conditions of equilibrium violations have been identified. The research results are to be used to propose violation negative influence compensation methods.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kargupta, H.; Stafford, B.; Hamzaoglu, I.

This paper describes an experimental parallel/distributed data mining system PADMA (PArallel Data Mining Agents) that uses software agents for local data accessing and analysis and a web based interface for interactive data visualization. It also presents the results of applying PADMA for detecting patterns in unstructured texts of postmortem reports and laboratory test data for Hepatitis C patients.

Using Metal Complex Ion-Molecule Reactions in a Miniature Rectilinear Ion Trap Mass Spectrometer to Detect Chemical Warfare Agents

NASA Astrophysics Data System (ADS)

Graichen, Adam M.; Vachet, Richard W.

2013-06-01

The gas-phase reactions of a series of coordinatively unsaturated [Ni(L)n]y+ complexes, where L is a nitrogen-containing ligand, with chemical warfare agent (CWA) simulants in a miniature rectilinear ion trap mass spectrometer were investigated as part of a new approach to detect CWAs. Results show that upon entering the vacuum system via a poly(dimethylsiloxane) (PDMS) membrane introduction, low concentrations of several CWA simulants, including dipropyl sulfide (simulant for mustard gas), acetonitrile (simulant for the nerve agent tabun), and diethyl phosphite (simulant for nerve agents sarin, soman, tabun, and VX), can react with metal complex ions generated by electrospray ionization (ESI), thereby providing a sensitive means of detecting these compounds. The [Ni(L)n]2+ complexes are found to be particularly reactive with the simulants of mustard gas and tabun, allowing their detection at low parts-per-billion (ppb) levels. These detection limits are well below reported exposure limits for these CWAs, which indicates the applicability of this new approach, and are about two orders of magnitude lower than electron ionization detection limits on the same mass spectrometer. The use of coordinatively unsaturated metal complexes as reagent ions offers the possibility of further tuning the ion-molecule chemistry so that desired compounds can be detected selectively or at even lower concentrations.

Biotechnology Research Requirements for Aeronautical Systems through the Year 2000. Volume 1

DTIC Science & Technology

1982-07-30

signature. Reducing the aero contain radic.?z,:"ve fallout. vehicle’s detectibility by reducing the optical, electro, acoustic, and infrared 0 Pulsed...arsenal devoted to agent doses. At this time, basic biochemical and chemical agents, reported use of mycotoxins and pharmacological data are minimal and...mass spectroscopy , quartz chemical agents must be developed. This research microbalances, Industrial hygiene dosimetry, damp should quantify human

Recent advances in rapid and ultrasensitive biosensors for infectious agents: lesson from Bacillus anthracis diagnostic sensors.

PubMed

Kim, Joungmok; Yoon, Moon-Young

2010-06-01

Here, we review the cumulative efforts to develop rapid and ultrasensitive diagnostic systems, especially for the infectious agent, Bacillus anthracis, as a model system. This Minireview focuses on demonstrating the features of various probes for target molecule detection and recent methods of signal generation within the biosensors. Also, we discuss the possibility of using peptides as next-generation probe molecules.

Using an object-based grid system to evaluate a newly developed EP approach to formulate SVMs as applied to the classification of organophosphate nerve agents

NASA Astrophysics Data System (ADS)

Land, Walker H., Jr.; Lewis, Michael; Sadik, Omowunmi; Wong, Lut; Wanekaya, Adam; Gonzalez, Richard J.; Balan, Arun

2004-04-01

This paper extends the classification approaches described in reference [1] in the following way: (1.) developing and evaluating a new method for evolving organophosphate nerve agent Support Vector Machine (SVM) classifiers using Evolutionary Programming, (2.) conducting research experiments using a larger database of organophosphate nerve agents, and (3.) upgrading the architecture to an object-based grid system for evaluating the classification of EP derived SVMs. Due to the increased threats of chemical and biological weapons of mass destruction (WMD) by international terrorist organizations, a significant effort is underway to develop tools that can be used to detect and effectively combat biochemical warfare. This paper reports the integration of multi-array sensors with Support Vector Machines (SVMs) for the detection of organophosphates nerve agents using a grid computing system called Legion. Grid computing is the use of large collections of heterogeneous, distributed resources (including machines, databases, devices, and users) to support large-scale computations and wide-area data access. Finally, preliminary results using EP derived support vector machines designed to operate on distributed systems have provided accurate classification results. In addition, distributed training time architectures are 50 times faster when compared to standard iterative training time methods.

Multispectral photoacoustic decomposition with localized regularization for detecting targeted contrast agent

NASA Astrophysics Data System (ADS)

Tavakoli, Behnoosh; Chen, Ying; Guo, Xiaoyu; Kang, Hyun Jae; Pomper, Martin; Boctor, Emad M.

2015-03-01

Targeted contrast agents can improve the sensitivity of imaging systems for cancer detection and monitoring the treatment. In order to accurately detect contrast agent concentration from photoacoustic images, we developed a decomposition algorithm to separate photoacoustic absorption spectrum into components from individual absorbers. In this study, we evaluated novel prostate-specific membrane antigen (PSMA) targeted agents for imaging prostate cancer. Three agents were synthesized through conjugating PSMA-targeting urea with optical dyes ICG, IRDye800CW and ATTO740 respectively. In our preliminary PA study, dyes were injected in a thin wall plastic tube embedded in water tank. The tube was illuminated with pulsed laser light using a tunable Q-switch ND-YAG laser. PA signal along with the B-mode ultrasound images were detected with a diagnostic ultrasound probe in orthogonal mode. PA spectrums of each dye at 0.5 to 20 μM concentrations were estimated using the maximum PA signal extracted from images which are obtained at illumination wavelengths of 700nm-850nm. Subsequently, we developed nonnegative linear least square optimization method along with localized regularization to solve the spectral unmixing. The algorithm was tested by imaging mixture of those dyes. The concentration of each dye was estimated with about 20% error on average from almost all mixtures albeit the small separation between dyes spectrums.

Design and Analysis of Cost-Efficient Sensor Deployment for Tracking Small UAS with Agent-Based Modeling.

PubMed

Shin, Sangmi; Park, Seongha; Kim, Yongho; Matson, Eric T

2016-04-22

Recently, commercial unmanned aerial systems (UAS) have gained popularity. However, these UAS are potential threats to people in terms of safety in public places, such as public parks or stadiums. To reduce such threats, we consider a design, modeling, and evaluation of a cost-efficient sensor system that detects and tracks small UAS. In this research, we focus on discovering the best sensor deployments by simulating different types and numbers of sensors in a designated area, which provide reasonable detection rates at low costs. Also, the system should cover the crowded areas more thoroughly than vacant areas to reduce direct threats to people underneath. This research study utilized the Agent-Based Modeling (ABM) technique to model a system consisting of independent and heterogeneous agents that interact with each other. Our previous work presented the ability to apply ABM to analyze the sensor configurations with two types of radars in terms of cost-efficiency. The results from the ABM simulation provide a list of candidate configurations and deployments that can be referred to for applications in the real world environment.

Design and Analysis of Cost-Efficient Sensor Deployment for Tracking Small UAS with Agent-Based Modeling

PubMed Central

Shin, Sangmi; Park, Seongha; Kim, Yongho; Matson, Eric T.

2016-01-01

Recently, commercial unmanned aerial systems (UAS) have gained popularity. However, these UAS are potential threats to people in terms of safety in public places, such as public parks or stadiums. To reduce such threats, we consider a design, modeling, and evaluation of a cost-efficient sensor system that detects and tracks small UAS. In this research, we focus on discovering the best sensor deployments by simulating different types and numbers of sensors in a designated area, which provide reasonable detection rates at low costs. Also, the system should cover the crowded areas more thoroughly than vacant areas to reduce direct threats to people underneath. This research study utilized the Agent-Based Modeling (ABM) technique to model a system consisting of independent and heterogeneous agents that interact with each other. Our previous work presented the ability to apply ABM to analyze the sensor configurations with two types of radars in terms of cost-efficiency. The results from the ABM simulation provide a list of candidate configurations and deployments that can be referred to for applications in the real world environment. PMID:27110790

Real-time, wide-area hyperspectral imaging sensors for standoff detection of explosives and chemical warfare agents

NASA Astrophysics Data System (ADS)

Gomer, Nathaniel R.; Tazik, Shawna; Gardner, Charles W.; Nelson, Matthew P.

2017-05-01

Hyperspectral imaging (HSI) is a valuable tool for the detection and analysis of targets located within complex backgrounds. HSI can detect threat materials on environmental surfaces, where the concentration of the target of interest is often very low and is typically found within complex scenery. Unfortunately, current generation HSI systems have size, weight, and power limitations that prohibit their use for field-portable and/or real-time applications. Current generation systems commonly provide an inefficient area search rate, require close proximity to the target for screening, and/or are not capable of making real-time measurements. ChemImage Sensor Systems (CISS) is developing a variety of real-time, wide-field hyperspectral imaging systems that utilize shortwave infrared (SWIR) absorption and Raman spectroscopy. SWIR HSI sensors provide wide-area imagery with at or near real time detection speeds. Raman HSI sensors are being developed to overcome two obstacles present in standard Raman detection systems: slow area search rate (due to small laser spot sizes) and lack of eye-safety. SWIR HSI sensors have been integrated into mobile, robot based platforms and handheld variants for the detection of explosives and chemical warfare agents (CWAs). In addition, the fusion of these two technologies into a single system has shown the feasibility of using both techniques concurrently to provide higher probability of detection and lower false alarm rates. This paper will provide background on Raman and SWIR HSI, discuss the applications for these techniques, and provide an overview of novel CISS HSI sensors focusing on sensor design and detection results.

Biosurveillance: A Review and Update

PubMed Central

Kman, Nicholas E.; Bachmann, Daniel J.

2012-01-01

Since the terrorist attacks and anthrax release in 2001, almost $32 billion has been allocated to biodefense and biosurveillance in the USA alone. Surveillance in health care refers to the continual systematic collection, analysis, interpretation, and dissemination of data. When attempting to detect agents of bioterrorism, surveillance can occur in several ways. Syndromic surveillance occurs by monitoring clinical manifestations of certain illnesses. Laboratory surveillance occurs by looking for certain markers or laboratory data, and environmental surveillance is the process by which the ambient air or environment is continually sampled for the presence of biological agents. This paper focuses on the ways by which we detect bioterrorism agents and the effectiveness of these systems. PMID:22242207

Stand-off CWA imaging system: second sight MS

NASA Astrophysics Data System (ADS)

Bernascolle, Philippe F.; Elichabe, Audrey; Fervel, Franck; Haumonté, Jean-Baptiste

2012-06-01

In recent years, several manufactures of IR imaging devices have launched commercial models applicable to a wide range of chemical species. These cameras are rugged and sufficiently sensitive to detect low concentrations of toxic and combustible gases. Bertin Technologies, specialized in the design and supply of innovating systems for industry, defense and health, has developed a stand-off gas imaging system using a multi-spectral infrared imaging technology. With this system, the gas cloud size, localization and evolution can be displayed in real time. This technology was developed several years ago in partnership with the CEB, a French MoD CBRN organization. The goal was to meet the need for early warning caused by a chemical threat. With a night & day efficiency of up to 5 km, this process is able to detect Chemical Warfare Agents (CWA), critical Toxic Industrial Compounds (TIC) and also flammable gases. The system has been adapted to detect industrial spillage, using off-the-shelf uncooled infrared cameras, allowing 24/7 surveillance without costly frequent maintenance. The changes brought to the system are in compliance with Military Specifications (MS) and primarily focus on the signal processing improving the classification of the detected products and on the simplification of the Human Machine Interface (HMI). Second Sight MS is the only mass produced, passive stand-off CWA imaging system with a wide angle (up to 60°) already used by several regular armies around the world. This paper examines this IR gas imager performance when exposed to several CWA, TIC and simulant compounds. First, we will describe the Second Sight MS system. The theory of gas detection, visualization and classification functions has already been described elsewhere, so we will just summarize it here. We will then present the main topic of this paper which is the results of the tests done in laboratory on live agents and in open field on simulant. The sensitivity threshold of the camera measured in laboratory, on some CWA (G, H agents...) and TIC (ammonia, sulfur dioxide...) will be given. The result of the detection and visualization of a gas cloud in open field testing for some simulants (DMMP, SF6) at a far distance will be also shown.

Rapid Detection of Pathogens

DOE Office of Scientific and Technical Information (OSTI.GOV)

David Perlin

2005-08-14

Pathogen identification is a crucial first defense against bioterrorism. A major emphasis of our national biodefense strategy is to establish fast, accurate and sensitive assays for diagnosis of infectious diseases agents. Such assays will ensure early and appropriate treatment of infected patients. Rapid diagnostics can also support infection control measures, which monitor and limit the spread of infectious diseases agents. Many select agents are highly transmissible in the early stages of disease, and it is critical to identify infected patients and limit the risk to the remainder of the population and to stem potential panic in the general population. Nucleicmore » acid-based molecular approaches for identification overcome many of the deficiencies associated with conventional culture methods by exploiting both large- and small-scale genomic differences between organisms. PCR-based amplification of highly conserved ribosomal RNA (rRNA) genes, intergenic sequences, and specific toxin genes is currently the most reliable approach for bacterial, fungal and many viral pathogenic agents. When combined with fluorescence-based oligonucleotide detection systems, this approach provides real-time, quantitative, high fidelity analysis capable of single nucleotide allelic discrimination (4). These probe systems offer rapid turn around time (<2 h) and are suitable for high throughput, automated multiplex operations that are critical for clinical diagnostic laboratories. In this pilot program, we have used molecular beacon technology invented at the Public health Research Institute to develop a new generation of molecular probes to rapidly detect important agents of infectious diseases. We have also developed protocols to rapidly extract nucleic acids from a variety of clinical specimen including and blood and tissue to for detection in the molecular assays. This work represented a cooperative research development program between the Kramer-Tyagi/Perlin labs on probe development and the Perlin lab in sample preparation and testing in animal models.« less

Protein detection system

DOEpatents

Fruetel, Julie A [Livermore, CA; Fiechtner, Gregory J [Bethesda, MD; Kliner, Dahv A. V. [San Ramon, CA; McIlroy, Andrew [Livermore, CA

2009-05-05

The present embodiment describes a miniature, microfluidic, absorption-based sensor to detect proteins at sensitivities comparable to LIF but without the need for tagging. This instrument utilizes fiber-based evanescent-field cavity-ringdown spectroscopy, in combination with faceted prism microchannels. The combination of these techniques will increase the effective absorption path length by a factor of 10.sup.3 to 10.sup.4 (to .about.1-m), thereby providing unprecedented sensitivity using direct absorption. The coupling of high-sensitivity absorption with high-performance microfluidic separation will enable real-time sensing of biological agents in aqueous samples (including aerosol collector fluids) and will provide a general method with spectral fingerprint capability for detecting specific bio-agents.

Devices, systems, and methods for conducting assays with improved sensitivity using sedimentation

DOEpatents

Schaff, Ulrich Y.; Koh, Chung-Yan; Sommer, Gregory J.

2016-04-05

Embodiments of the present invention are directed toward devices, systems, and method for conducting assays using sedimentation. In one example, a method includes layering a mixture on a density medium, subjecting sedimentation particles in the mixture to sedimentation forces to cause the sedimentation particles to move to a detection area through a density medium, and detecting a target analyte in a detection region of the sedimentation channel. In some examples, the sedimentation particles and labeling agent may have like charges to reduce non-specific binding of labeling agent and sedimentation particles. In some examples, the density medium is provided with a separation layer for stabilizing the assay during storage and operation. In some examples, the sedimentation channel may be provided with a generally flat sedimentation chamber for dispersing the particle pellet over a larger surface area.

Devices, systems, and methods for conducting assays with improved sensitivity using sedimentation

DOEpatents

Schaff, Ulrich Y; Koh, Chung-Yan; Sommer, Gregory J

2015-02-24

Embodiments of the present invention are directed toward devices, systems, and method for conducting assays using sedimentation. In one example, a method includes layering a mixture on a density medium, subjecting sedimentation particles in the mixture to sedimentation forces to cause the sedimentation particles to move to a detection area through a density medium, and detecting a target analyte in a detection region of the sedimentation channel. In some examples, the sedimentation particles and labeling agent may have like charges to reduce non-specific binding of labeling agent and sedimentation particles. In some examples, the density medium is provided with a separation layer for stabilizing the assay during storage and operation. In some examples, the sedimentation channel may be provided with a generally flat sedimentation chamber for dispersing the particle pellet over a larger surface area.

Species-Specific Detection of Mycosphaerella polygoni-cuspidati as a Biological Control Agent for Fallopia japonica by PCR Assay.

PubMed

Kurose, Daisuke; Furuya, Naruto; Saeki, Tetsuya; Tsuchiya, Kenichi; Tsushima, Seiya; Seier, Marion K

2016-10-01

The ascomycete fungus Mycosphaerella polygoni-cuspidati has been undergoing evaluation as a potential classical biological control agent for the invasive weed Fallopia japonica (Japanese knotweed), which has become troublesome in Europe and North America. In advance of the potential release of a biocontrol agent into a new environment, it is crucial to develop an effective monitoring system to enable the evaluation of agent establishment and dispersal within the target host population, as well as any potential attacks on non-target species. Therefore, a primer pair was designed for direct, rapid, and specific detection of the Japanese knotweed pathogen M. polygoni-cuspidati based on the sequences of the internal transcribed spacer regions including the 5.8S rDNA. A PCR product of approximately 298 bp was obtained only when the DNA extracted from mycelial fragments of M. polygoni-cuspidati was used. The lower limit of detection of the PCR method was 100 fg of genomic DNA. Using the specific primer pair, M. polygoni-cuspidati could be detected from both naturally and artificially infected Japanese knotweed plants. No amplification was observed for other Mycosphaerella spp. or fungal endophytes isolated from F. japonica. The designed primer pair is thus effective for the specific detection of M. polygoni-cuspidati in planta.

A solid phase enzyme-linked immunosorbent assay for the antigenic detection of Legionella pneumophila (serogroup 1): A compliment for the space station diagnostic capability

NASA Technical Reports Server (NTRS)

Hejtmancik, Kelly E.

1987-01-01

It is necessary that an adequate microbiology capability be provided as part of the Health Maintenance Facility (HMF) to support expected microbial disease events and environmental monitoring during long periods of space flight. The application of morphological and biochemical studies to confirm the presence of certain bacterial and fungal disease agents are currently available and under consideration. This confirmation would be facilitated through employment of serological methods to aid in the identification of bacterial, fungal, and viral agents. A number of serological approaches are currently being considered, including the use of Enzyme Linked Immunosorbent Assay (ELISA) technology, which could be utilized during microgravity conditions. A solid phase, membrane supported ELISA for the detection of Legionella pneumophila, an expected disease agent, was developed to show a potential model system that would meet the HMF requirements and specifications for the future space station. These studies demonstrate the capability of membrane supported ELISA systems for identification of expected microbial disease agents as part of the HMF.

oRis: multiagents approach for image processing

NASA Astrophysics Data System (ADS)

Rodin, Vincent; Harrouet, Fabrice; Ballet, Pascal; Tisseau, Jacques

1998-09-01

In this article, we present a parallel image processing system based on the concept of reactive agents. This means that, in our system, each agent has a very simple behavior which allows it to take a decision (find out an edge, a region, ...) according to its position in the image and to the information enclosed in it. Our system lies in the oRis language, which allows to describe very finely and simply the agents' behaviors. In fact, oRis is an interpreted and dynamic multiagent language. First of all, oRis is an object language with the use of classes regrouping attributes and methods. The syntax is close to the C++ language and includes notions of multiple inheritance, oRis is also an agent language: every object with a method `main()' becomes an agent. This method is cyclically executed by the system scheduler and corresponds to the agent behavior. We also present an application made with oRis. This application allows to detect concentric striae located on different natural `objects' (age-rings of tree, fish otolith growth rings, striae of some minerals, ...). The stopping of the multiagent system is implemented through a technique issued from immunology: the apoptosis.

Imaging of tumor hypermetabolism with near-infrared fluorescence contrast agents

NASA Astrophysics Data System (ADS)

Chen, Yu; Zheng, Gang; Zhang, Zhihong; Blessington, Dana; Intes, Xavier; Achilefu, Samuel I.; Chance, Britton

2004-08-01

We have developed a high sensitivity near-infrared (NIR) optical imaging system for non-invasive cancer detection through molecular labeled fluorescent contrast agents. Near-infrared (NIR) imaging can probe tissue deeply thus possess the potential for non-invasively detection of breast or lymph node cancer. Recent developments in molecular beacons can selectively label various pre-cancer/cancer signatures and provide high tumor to background contrast. To increase the sensitivity in detecting fluorescent photons and the accuracy of localization, phase cancellation (in- and anti-phase) device is employed. This frequency-domain system utilizes the interference-like pattern of diffuse photon density wave to achieve high detection sensitivity and localization accuracy for the fluorescent heterogeneity embedded inside the scattering media. The opto-electronic system consists of the laser sources, fiber optics, interference filter to select the fluorescent photons and the high sensitivity photon detector (photomultiplier tube). The source-detector pair scans the tissue surface in multiple directions and the two-dimensional localization image can be obtained using goniometric reconstruction. In vivo measurements with tumor-bearing mouse model using the novel Cypate-mono-2-deoxy-glucose (Cypate-2-D-Glucosamide) fluorescent contrast agent, which targets the enhanced tumor glycolysis, demonstrated the feasibility on detection of 2 cm deep subsurface tumor in the tissue-like medium, with a localization accuracy within 2 ~ 3 mm. This instrument has the potential for tumor diagnosis and imaging, and the accuracy of the localization suggests that this system could help to guide the clinical fine-needle biopsy. This portable device would be complementary to X-ray mammogram and provide add-on information on early diagnosis and localization of early breast tumor.

Love-Wave Sensors Combined with Microfluidics for Fast Detection of Biological Warfare Agents

PubMed Central

Matatagui, Daniel; Fontecha, José Luis; Fernández, María Jesús; Gràcia, Isabel; Cané, Carles; Santos, José Pedro; Horrillo, María Carmen

2014-01-01

The following paper examines a time-efficient method for detecting biological warfare agents (BWAs). The method is based on a system of a Love-wave immunosensor combined with a microfluidic chip which detects BWA samples in a dynamic mode. In this way a continuous flow-through of the sample is created, promoting the reaction between antigen and antibody and allowing a fast detection of the BWAs. In order to prove this method, static and dynamic modes have been simulated and different concentrations of BWA simulants have been tested with two immunoreactions: phage M13 has been detected using the mouse monoclonal antibody anti-M13 (AM13), and the rabbit immunoglobulin (Rabbit IgG) has been detected using the polyclonal antibody goat anti-rabbit (GAR). Finally, different concentrations of each BWA simulants have been detected with a fast response time and a desirable level of discrimination among them has been achieved. PMID:25029282

A support vector machine approach to the automatic identification of fluorescence spectra emitted by biological agents

NASA Astrophysics Data System (ADS)

Gelfusa, M.; Murari, A.; Lungaroni, M.; Malizia, A.; Parracino, S.; Peluso, E.; Cenciarelli, O.; Carestia, M.; Pizzoferrato, R.; Vega, J.; Gaudio, P.

2016-10-01

Two of the major new concerns of modern societies are biosecurity and biosafety. Several biological agents (BAs) such as toxins, bacteria, viruses, fungi and parasites are able to cause damage to living systems either humans, animals or plants. Optical techniques, in particular LIght Detection And Ranging (LIDAR), based on the transmission of laser pulses and analysis of the return signals, can be successfully applied to monitoring the release of biological agents into the atmosphere. It is well known that most of biological agents tend to emit specific fluorescence spectra, which in principle allow their detection and identification, if excited by light of the appropriate wavelength. For these reasons, the detection of the UVLight Induced Fluorescence (UV-LIF) emitted by BAs is particularly promising. On the other hand, the stand-off detection of BAs poses a series of challenging issues; one of the most severe is the automatic discrimination between various agents which emit very similar fluorescence spectra. In this paper, a new data analysis method, based on a combination of advanced filtering techniques and Support Vector Machines, is described. The proposed approach covers all the aspects of the data analysis process, from filtering and denoising to automatic recognition of the agents. A systematic series of numerical tests has been performed to assess the potential and limits of the proposed methodology. The first investigations of experimental data have already given very encouraging results.

Acoustic cavitation of individual ultrasound contrast agent microbubbles confined in capillaries

NASA Astrophysics Data System (ADS)

Almaqwashi, Ali; McIntyre, David; Ammi, Azzdine

2011-10-01

Ultrasound targeted therapies mainly rely on the inertial cavitation of ultrasound contrast agent (UCA) microbubbles. Our objective is to determine the cavitation acoustic pressure threshold for the destruction of UCA microbubbles inside cellulose capillaries. Acoustic emission from individual Optison microbubbles confined inside a 200-μm diameter capillary was detected using a passive cavitation detection system. Excitation signals from a 2.25 MHz transmitter were applied to the microbubbles while their acoustic emission was detected by a broadband 15 MHz receiver. Time traces were recorded (100 MHz sampling, 12- bit), and frequency-domain analysis of the received signals was performed to characterize microbubble cavitation. The cavitation acoustic pressure threshold was found to be 1 MPa inside the capillary in comparison with ˜0.7 MPa previously reported for unconfined UCA microbubbles. This work provides a clearer understanding of the role of ultrasound contrast agent dynamics inside a capillary.

A common-path optical coherence tomography based electrode for structural imaging of nerves and recording of action potentials

NASA Astrophysics Data System (ADS)

Islam, M. Shahidul; Haque, Md. Rezuanul; Oh, Christian M.; Wang, Yan; Park, B. Hyle

2013-03-01

Current technologies for monitoring neural activity either use different variety of electrodes (electrical recording) or require contrast agents introduced exogenously or through genetic modification (optical imaging). Here we demonstrate an optical method for non-contact and contrast agent free detection of nerve activity using phase-resolved optical coherence tomography (pr-OCT). A common-path variation of the pr-OCT is recently implemented and the developed system demonstrated the capability to detect rapid transient structural changes that accompany neural spike propagation. No averaging over multiple trials was required, indicating its capability of single-shot detection of individual impulses from functionally stimulated Limulus optic nerve. The strength of this OCT-based optical electrode is that it is a contactless method and does not require any exogenous contrast agent. With further improvements in accuracy and sensitivity, this optical electrode will play a complementary role to the existing recording technologies in future.

Detection of vapor-phase organophosphate threats using wearable conformable integrated epidermal and textile wireless biosensor systems.

PubMed

Mishra, Rupesh K; Martín, Aida; Nakagawa, Tatsuo; Barfidokht, Abbas; Lu, Xialong; Sempionatto, Juliane R; Lyu, Kay Mengjia; Karajic, Aleksandar; Musameh, Mustafa M; Kyratzis, Ilias L; Wang, Joseph

2018-03-15

Flexible epidermal tattoo and textile-based electrochemical biosensors have been developed for vapor-phase detection of organophosphorus (OP) nerve agents. These new wearable sensors, based on stretchable organophosphorus hydrolase (OPH) enzyme electrodes, are coupled with a fully integrated conformal flexible electronic interface that offers rapid and selective square-wave voltammetric detection of OP vapor threats and wireless data transmission to a mobile device. The epidermal tattoo and textile sensors display a good reproducibility (with RSD of 2.5% and 4.2%, respectively), along with good discrimination against potential interferences and linearity over the 90-300mg/L range, with a sensitivity of 10.7µA∙cm 3 ∙mg -1 (R 2 = 0.983) and detection limit of 12mg/L in terms of OP air density. Stress-enduring inks, used for printing the electrode transducers, ensure resilience against mechanical deformations associated with textile and skin-based on-body sensing operations. Theoretical simulations are used to estimate the OP air density over the sensor surface. These fully integrated wearable wireless tattoo and textile-based nerve-agent vapor biosensor systems offer considerable promise for rapid warning regarding personal exposure to OP nerve-agent vapors in variety of decentralized security applications. Copyright © 2017 Elsevier B.V. All rights reserved.

Viral Susceptibility Range of the Fathead Minnow (Pimephales promelas) Poikilothermic Cell Line 1

PubMed Central

Solis, Juan; Mora, Emilio C.

1970-01-01

The viral susceptibility range of a poikilothermic cell line derived from the fathead minnow (Pimephales promelas) (FHM) to infection by a number of homoiothermic viruses representing most of the presently recognized viral groups and a member of the psittacosis-lymphogranuloma-trachoma group of agents was studied. All infectious agents, except poliovirus types 1 and 3, infectious bursal agent, and an avian infectious bronchitis virus (IBV) strain, readily multiplied in the FHM cell culture system, producing a detectable cytopathic effect. Although inconclusive evidence was obtained with two other avian IBV strains, these results indicated the ability of the FHM cell culture system to readily support the propagation of a variety of cytopathogenic homoiothermic viral agents. PMID:5461163

Antigen detection systems

USDA-ARS?s Scientific Manuscript database

Infectious agents or their constituent parts (antigens or nucleic acids) can be detected in fresh, frozen, or fixed tissues or other specimens, using a variety of direct or indirect assays. The assays can be modified to yield the greatest sensitivity and specificity but in most cases a particular m...

Detection of early changes in lung cell cytology by flow-systems analysis techniques, July 1--December 31, 1975

DOE Office of Scientific and Technical Information (OSTI.GOV)

Steinkamp, J.A.; Ingram, M.; Hansen, K.M.

1976-03-01

This report summarizes results of preliminary experiments to demonstrate the feasibility of using automated flow-systems analysis in detecting early changes of respiratory epithelium exposed to physical and chemical agents associated with the by-products of nonnuclear energy production. The Syrian hamster was selected as the experimental test animal to begin investigation of the effects of toxic agents to cells of the respiratory tract. Since initiation of the program approximately six months ago, the goals have been acquisition of adequate numbers of exfoliated cells from the lung; adaptation of cytological techniques developed on human exfoliated gynecological samples to hamster lung epithelium formore » obtaining single-cell suspensions; utilization of existing cell staining methods to measure DNA content in lung cells; and analysis of DNA content and cell size. As the flow-system cell analysis technology is adapted to the measurement of exfoliated lung cells, rapid and quantitative determination of early changes in the physical and biochemical cellular properties will be attempted as a function of exposure to the toxic agents. (auth)« less

Optimized Sensor Network and Multi-Agent Decision Support for Smart Traffic Light Management.

PubMed

Cruz-Piris, Luis; Rivera, Diego; Fernandez, Susel; Marsa-Maestre, Ivan

2018-02-02

One of the biggest challenges in modern societies is to solve vehicular traffic problems. Sensor networks in traffic environments have contributed to improving the decision-making process of Intelligent Transportation Systems. However, one of the limiting factors for the effectiveness of these systems is in the deployment of sensors to provide accurate information about the traffic. Our proposal is using the centrality measurement of a graph as a base to locate the best locations for sensor installation in a traffic network. After integrating these sensors in a simulation scenario, we define a Multi-Agent Systems composed of three types of agents: traffic light management agents, traffic jam detection agents, and agents that control the traffic lights at an intersection. The ultimate goal of these Multi-Agent Systems is to improve the trip duration for vehicles in the network. To validate our solution, we have developed the needed elements for modelling the sensors and agents in the simulation environment. We have carried out experiments using the Simulation of Urban MObility (SUMO) traffic simulator and the Travel and Activity PAtterns Simulation (TAPAS) Cologne traffic scenario. The obtained results show that our proposal allows to reduce the sensor network while still obtaining relevant information to have a global view of the environment. Finally, regarding the Multi-Agent Systems, we have carried out experiments that show that our proposal is able to improve other existing solutions such as conventional traffic light management systems (static or dynamic) in terms of reduction of vehicle trip duration and reduction of the message exchange overhead in the sensor network.

Optimized Sensor Network and Multi-Agent Decision Support for Smart Traffic Light Management

PubMed Central

2018-01-01

One of the biggest challenges in modern societies is to solve vehicular traffic problems. Sensor networks in traffic environments have contributed to improving the decision-making process of Intelligent Transportation Systems. However, one of the limiting factors for the effectiveness of these systems is in the deployment of sensors to provide accurate information about the traffic. Our proposal is using the centrality measurement of a graph as a base to locate the best locations for sensor installation in a traffic network. After integrating these sensors in a simulation scenario, we define a Multi-Agent Systems composed of three types of agents: traffic light management agents, traffic jam detection agents, and agents that control the traffic lights at an intersection. The ultimate goal of these Multi-Agent Systems is to improve the trip duration for vehicles in the network. To validate our solution, we have developed the needed elements for modelling the sensors and agents in the simulation environment. We have carried out experiments using the Simulation of Urban MObility (SUMO) traffic simulator and the Travel and Activity PAtterns Simulation (TAPAS) Cologne traffic scenario. The obtained results show that our proposal allows to reduce the sensor network while still obtaining relevant information to have a global view of the environment. Finally, regarding the Multi-Agent Systems, we have carried out experiments that show that our proposal is able to improve other existing solutions such as conventional traffic light management systems (static or dynamic) in terms of reduction of vehicle trip duration and reduction of the message exchange overhead in the sensor network. PMID:29393884

Small animal imaging platform for quantitative assessment of short-wave infrared-emitting contrast agents

NASA Astrophysics Data System (ADS)

Hu, Philip; Mingozzi, Marco; Higgins, Laura M.; Ganapathy, Vidya; Zevon, Margot; Riman, Richard E.; Roth, Charles M.; Moghe, Prabhas V.; Pierce, Mark C.

2015-03-01

We report the design, calibration, and testing of a pre-clinical small animal imaging platform for use with short-wave infrared (SWIR) emitting contrast agents. Unlike materials emitting at visible or near-infrared wavelengths, SWIR-emitting agents require detection systems with sensitivity in the 1-2 μm wavelength region, beyond the range of commercially available small animal imagers. We used a collimated 980 nm laser beam to excite rare-earth-doped NaYF4:Er,Yb nanocomposites, as an example of a SWIR emitting material under development for biomedical imaging applications. This beam was raster scanned across the animal, with fluorescence in the 1550 nm wavelength region detected by an InGaAs area camera. Background adjustment and intensity non-uniformity corrections were applied in software. The final SWIR fluorescence image was overlaid onto a standard white-light image for registration of contrast agent uptake with respect to anatomical features.

Scaling laws of strategic behavior and size heterogeneity in agent dynamics

NASA Astrophysics Data System (ADS)

Vaglica, Gabriella; Lillo, Fabrizio; Moro, Esteban; Mantegna, Rosario N.

2008-03-01

We consider the financial market as a model system and study empirically how agents strategically adjust the properties of large orders in order to meet their preference and minimize their impact. We quantify this strategic behavior by detecting scaling relations between the variables characterizing the trading activity of different institutions. We also observe power-law distributions in the investment time horizon, in the number of transactions needed to execute a large order, and in the traded value exchanged by large institutions, and we show that heterogeneity of agents is a key ingredient for the emergence of some aggregate properties characterizing this complex system.

In vivo tumor characterization using both MR and optical contrast agents with a hybrid MRI-DOT system

NASA Astrophysics Data System (ADS)

Lin, Yuting; Ghijsen, Michael; Thayer, David; Nalcioglu, Orhan; Gulsen, Gultekin

2011-03-01

Dynamic contrast enhanced MRI (DCE-MRI) has been proven to be the most sensitive modality in detecting breast lesions. Currently available MR contrast agent, Gd-DTPA, is a low molecular weight extracellular agent and can diffuse freely from the vascular space into interstitial space. Due to this reason, DCE-MRI has low sensitivity in differentiating benign and malignant tumors. Meanwhile, diffuse optical tomography (DOT) can be used to provide enhancement kinetics of an FDA approved optical contrast agent, ICG, which behaves like a large molecular weight optical agent due to its binding to albumin. The enhancement kinetics of ICG may have a potential to distinguish between the malignant and benign tumors and hence improve the specificity. Our group has developed a high speed hybrid MRI-DOT system. The DOT is a fully automated, MR-compatible, multi-frequency and multi-spectral imaging system. Fischer-344 rats bearing subcutaneous R3230 tumor are injected simultaneously with Gd-DTPA (0.1nmol/kg) and IC-Green (2.5mg/kg). The enhancement kinetics of both contrast agents are recorded simultaneously with this hybrid MRI-DOT system and evaluated for different tumors.

Spectral pattern recognition of controlled substances in street samples using artificial neural network system

NASA Astrophysics Data System (ADS)

Poryvkina, Larisa; Aleksejev, Valeri; Babichenko, Sergey M.; Ivkina, Tatjana

2011-04-01

The NarTest fluorescent technique is aimed at the detection of analyte of interest in street samples by recognition of its specific spectral patterns in 3-dimentional Spectral Fluorescent Signatures (SFS) measured with NTX2000 analyzer without chromatographic or other separation of controlled substances from a mixture with cutting agents. The illicit drugs have their own characteristic SFS features which can be used for detection and identification of narcotics, however typical street sample consists of a mixture with cutting agents: adulterants and diluents. Many of them interfere the spectral shape of SFS. The expert system based on Artificial Neural Networks (ANNs) has been developed and applied for such pattern recognition in SFS of street samples of illicit drugs.

Devices, systems, and methods for detecting nucleic acids using sedimentation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Koh, Chung-Yan; Schaff, Ulrich Y.; Sommer, Gregory J.

Embodiments of the present invention are directed toward devices, systems, and method for conducting nucleic acid purification and quantification using sedimentation. In one example, a method includes generating complexes which bind to a plurality of beads in a fluid sample, individual ones of the complexes comprising a nucleic acid molecule such as DNA or RNA and a labeling agent. The plurality of beads including the complexes may be transported through a density media, wherein the density media has a density lower than a density of the beads and higher than a density of the fluid sample, and wherein the transportingmore » occurs, at least in part, by sedimentation. Signal may be detected from the labeling agents of the complexes.« less

Mid-infrared gas absorption sensor based on a broadband external cavity quantum cascade laser

NASA Astrophysics Data System (ADS)

Sun, Juan; Deng, Hao; Liu, Ningwu; Wang, Hongliang; Yu, Benli; Li, Jingsong

2016-12-01

We developed a laser absorption sensor based on a pulsed, broadband tunable external cavity quantum cascade laser (ECQCL) centered at 1285 cm-1. Unlike traditional infrared spectroscopy system, a quartz crystal tuning fork (QCTF) as a light detector was used for laser signal detection. Fast Fourier transform was applied to extract vibration intensity information of QCTF. The sensor system is successfully tested on nitrous oxide (N2O) spectroscopy measurements and compared with a standard infrared detector. The wide wavelength tunability of ECQCL will allow us to access the fundamental vibrational bands of many chemical agents, which are well-suited for trace explosive, chemical warfare agent, and toxic industrial chemical detection and spectroscopic analysis.

Mid-infrared gas absorption sensor based on a broadband external cavity quantum cascade laser.

PubMed

Sun, Juan; Deng, Hao; Liu, Ningwu; Wang, Hongliang; Yu, Benli; Li, Jingsong

2016-12-01

We developed a laser absorption sensor based on a pulsed, broadband tunable external cavity quantum cascade laser (ECQCL) centered at 1285 cm -1 . Unlike traditional infrared spectroscopy system, a quartz crystal tuning fork (QCTF) as a light detector was used for laser signal detection. Fast Fourier transform was applied to extract vibration intensity information of QCTF. The sensor system is successfully tested on nitrous oxide (N 2 O) spectroscopy measurements and compared with a standard infrared detector. The wide wavelength tunability of ECQCL will allow us to access the fundamental vibrational bands of many chemical agents, which are well-suited for trace explosive, chemical warfare agent, and toxic industrial chemical detection and spectroscopic analysis.

Organic contaminants in onsite wastewater treatment systems

USGS Publications Warehouse

Conn, K.E.; Siegrist, R.L.; Barber, L.B.; Brown, G.K.

2007-01-01

Wastewater from thirty onsite wastewater treatment systems was sampled during a reconnaissance field study to quantify bulk parameters and the occurrence of organic wastewater contaminants including endocrine disrupting compounds in treatment systems representing a variety of wastewater sources and treatment processes and their receiving environments. Bulk parameters ranged in concentrations representative of the wide variety of wastewater sources (residential vs. non-residential). Organic contaminants such as sterols, surfactant metabolites, antimicrobial agents, stimulants, metal-chelating agents, and other consumer product chemicals, measured by gas chromatography/mass spectrometry were detected frequently in onsite system wastewater. Wastewater composition was unique between source type likely due to differences in source water and chemical usage. Removal efficiencies varied by engineered treatment type and physicochemical properties of the contaminant, resulting in discharge to the soil treatment unit at ecotoxicologically-relevant concentrations. Organic wastewater contaminants were detected less frequently and at lower concentrations in onsite system receiving environments. Understanding the occurrence and fate of organic wastewater contaminants in onsite wastewater treatment systems will aid in minimizing risk to ecological and human health.

Using Swarming Agents for Scalable Security in Large Network Environments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Crouse, Michael; White, Jacob L.; Fulp, Errin W.

2011-09-23

The difficulty of securing computer infrastructures increases as they grow in size and complexity. Network-based security solutions such as IDS and firewalls cannot scale because of exponentially increasing computational costs inherent in detecting the rapidly growing number of threat signatures. Hostbased solutions like virus scanners and IDS suffer similar issues, and these are compounded when enterprises try to monitor these in a centralized manner. Swarm-based autonomous agent systems like digital ants and artificial immune systems can provide a scalable security solution for large network environments. The digital ants approach offers a biologically inspired design where each ant in the virtualmore » colony can detect atoms of evidence that may help identify a possible threat. By assembling the atomic evidences from different ant types the colony may detect the threat. This decentralized approach can require, on average, fewer computational resources than traditional centralized solutions; however there are limits to its scalability. This paper describes how dividing a large infrastructure into smaller managed enclaves allows the digital ant framework to effectively operate in larger environments. Experimental results will show that using smaller enclaves allows for more consistent distribution of agents and results in faster response times.« less

Point detection of bacterial and viral pathogens using oral samples

NASA Astrophysics Data System (ADS)

Malamud, Daniel

2008-04-01

Oral samples, including saliva, offer an attractive alternative to serum or urine for diagnostic testing. This is particularly true for point-of-use detection systems. The various types of oral samples that have been reported in the literature are presented here along with the wide variety of analytes that have been measured in saliva and other oral samples. The paper focuses on utilizing point-detection of infectious disease agents, and presents work from our group on a rapid test for multiple bacterial and viral pathogens by monitoring a series of targets. It is thus possible in a single oral sample to identify multiple pathogens based on specific antigens, nucleic acids, and host antibodies to those pathogens. The value of such a technology for detecting agents of bioterrorism at remote sites is discussed.

Expansion of space station diagnostic capability to include serological identification of viral and bacterial infections

NASA Technical Reports Server (NTRS)

Hejtmancik, Kelly E.

1987-01-01

It is necessary that an adequate microbiology capability be provided as part of the Health Maintenance Facility (HMF) to support expected microbial disease events during long periods of space flight. The applications of morphological and biochemical studies to confirm the presence of certain bacterial and fungal disease agents are currently available and under consideration. This confirmation would be greatly facilitated through employment of serological methods to aid in the identification for not only bacterial and fungal agents, but viruses as well. A number of serological approached were considered, particularly the use of Enzyme Linked Immunosorbent Assays (ELISAs), which could be utilized during space flight conditions. A solid phase, membrane supported ELISA for the detection of Bordetella pertussis was developed to show a potential model system that would meet the HMF requirements and specifications for the future space station. A second model system for the detection of Legionella pneumophilia, an expected bacterial disease agent, is currently under investigation.

Massively multiplexed microbial identification using resequencing DNA microarrays for outbreak investigation

NASA Astrophysics Data System (ADS)

Leski, T. A.; Ansumana, R.; Jimmy, D. H.; Bangura, U.; Malanoski, A. P.; Lin, B.; Stenger, D. A.

2011-06-01

Multiplexed microbial diagnostic assays are a promising method for detection and identification of pathogens causing syndromes characterized by nonspecific symptoms in which traditional differential diagnosis is difficult. Also such assays can play an important role in outbreak investigations and environmental screening for intentional or accidental release of biothreat agents, which requires simultaneous testing for hundreds of potential pathogens. The resequencing pathogen microarray (RPM) is an emerging technological platform, relying on a combination of massively multiplex PCR and high-density DNA microarrays for rapid detection and high-resolution identification of hundreds of infectious agents simultaneously. The RPM diagnostic system was deployed in Sierra Leone, West Africa in collaboration with Njala University and Mercy Hospital Research Laboratory located in Bo. We used the RPM-Flu microarray designed for broad-range detection of human respiratory pathogens, to investigate a suspected outbreak of avian influenza in a number of poultry farms in which significant mortality of chickens was observed. The microarray results were additionally confirmed by influenza specific real-time PCR. The results of the study excluded the possibility that the outbreak was caused by influenza, but implicated Klebsiella pneumoniae as a possible pathogen. The outcome of this feasibility study confirms that application of broad-spectrum detection platforms for outbreak investigation in low-resource locations is possible and allows for rapid discovery of the responsible agents, even in cases when different agents are suspected. This strategy enables quick and cost effective detection of low probability events such as outbreak of a rare disease or intentional release of a biothreat agent.

A Review of Chemical Warfare Agent (CWA) Detector Technologies and Commercial-Off-The-Shelf Items

DTIC Science & Technology

2009-03-01

Environmental Health Perspectives 1994, 102, 18-38. 21. La Franchi , P., Chemical and Biological Weapons: The War from Hell. ADM September, 1995, pp 9-10...One-to-Five Gas Monitor with VOC Detection. In ENVCO Global . DSTO-GD-0570 98 152. MultiRAE Plus. In RAE Systems: San Jose, CA. 153. ToxiRAE Plus PID...158. Rippen, M., Chemical and Biological Agent Sensor/Detector Systems Technology Development for Applications in the Global War on Terrorism. In

Handheld and mobile hyperspectral imaging sensors for wide-area standoff detection of explosives and chemical warfare agents

NASA Astrophysics Data System (ADS)

Gomer, Nathaniel R.; Gardner, Charles W.; Nelson, Matthew P.

2016-05-01

Hyperspectral imaging (HSI) is a valuable tool for the investigation and analysis of targets in complex background with a high degree of autonomy. HSI is beneficial for the detection of threat materials on environmental surfaces, where the concentration of the target of interest is often very low and is typically found within complex scenery. Two HSI techniques that have proven to be valuable are Raman and shortwave infrared (SWIR) HSI. Unfortunately, current generation HSI systems have numerous size, weight, and power (SWaP) limitations that make their potential integration onto a handheld or field portable platform difficult. The systems that are field-portable do so by sacrificing system performance, typically by providing an inefficient area search rate, requiring close proximity to the target for screening, and/or eliminating the potential to conduct real-time measurements. To address these shortcomings, ChemImage Sensor Systems (CISS) is developing a variety of wide-field hyperspectral imaging systems. Raman HSI sensors are being developed to overcome two obstacles present in standard Raman detection systems: slow area search rate (due to small laser spot sizes) and lack of eye-safety. SWIR HSI sensors have been integrated into mobile, robot based platforms and handheld variants for the detection of explosives and chemical warfare agents (CWAs). In addition, the fusion of these two technologies into a single system has shown the feasibility of using both techniques concurrently to provide higher probability of detection and lower false alarm rates. This paper will provide background on Raman and SWIR HSI, discuss the applications for these techniques, and provide an overview of novel CISS HSI sensors focused on sensor design and detection results.

Method and system for monitoring environmental conditions

DOEpatents

Kulesz, James J [Oak Ridge, TN; Lee, Ronald W [Oak Ridge, TN

2010-11-16

A system for detecting the occurrence of anomalies includes a plurality of spaced apart nodes, with each node having adjacent nodes, each of the nodes having one or more sensors associated with the node and capable of detecting anomalies, and each of the nodes having a controller connected to the sensors associated with the node. The system also includes communication links between adjacent nodes, whereby the nodes form a network. At least one software agent is capable of changing the operation of at least one of the controllers in response to the detection of an anomaly by a sensor.

Iodine Coulometry of Various Reducing Agents Including Thiols with Online Photocell Detection Coupled to a Multifunctional Chemical Analysis Station to Eliminate Student End Point Detection by Eye

ERIC Educational Resources Information Center

Padilla Mercado, Jeralyne B.; Coombs, Eri M.; De Jesus, Jenny P.; Bretz, Stacey Lowery; Danielson, Neil D.

2018-01-01

Multifunctional chemical analysis (MCA) systems provide a viable alternative for large scale instruction while supporting a hands-on approach to more advanced instrumentation. These systems are robust and typically use student stations connected to a remote central computer for data collection, minimizing the need for computers at every student…

Agent Orange

DTIC Science & Technology

2007-05-24

TYPE 3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 5d. PROJECT NUMBER 5e...and X-Ray devices to detect radioactivity . All these systems would provide much needed air support and detection systems that would previously be...dangerous for manned aircraft to provide or would prove too difficult for ground vehicles to get to. These sampling techniques could also be used for

DyHAP: Dynamic Hybrid ANFIS-PSO Approach for Predicting Mobile Malware.

PubMed

Afifi, Firdaus; Anuar, Nor Badrul; Shamshirband, Shahaboddin; Choo, Kim-Kwang Raymond

2016-01-01

To deal with the large number of malicious mobile applications (e.g. mobile malware), a number of malware detection systems have been proposed in the literature. In this paper, we propose a hybrid method to find the optimum parameters that can be used to facilitate mobile malware identification. We also present a multi agent system architecture comprising three system agents (i.e. sniffer, extraction and selection agent) to capture and manage the pcap file for data preparation phase. In our hybrid approach, we combine an adaptive neuro fuzzy inference system (ANFIS) and particle swarm optimization (PSO). Evaluations using data captured on a real-world Android device and the MalGenome dataset demonstrate the effectiveness of our approach, in comparison to two hybrid optimization methods which are differential evolution (ANFIS-DE) and ant colony optimization (ANFIS-ACO).

DyHAP: Dynamic Hybrid ANFIS-PSO Approach for Predicting Mobile Malware

PubMed Central

Afifi, Firdaus; Anuar, Nor Badrul; Shamshirband, Shahaboddin

2016-01-01

To deal with the large number of malicious mobile applications (e.g. mobile malware), a number of malware detection systems have been proposed in the literature. In this paper, we propose a hybrid method to find the optimum parameters that can be used to facilitate mobile malware identification. We also present a multi agent system architecture comprising three system agents (i.e. sniffer, extraction and selection agent) to capture and manage the pcap file for data preparation phase. In our hybrid approach, we combine an adaptive neuro fuzzy inference system (ANFIS) and particle swarm optimization (PSO). Evaluations using data captured on a real-world Android device and the MalGenome dataset demonstrate the effectiveness of our approach, in comparison to two hybrid optimization methods which are differential evolution (ANFIS-DE) and ant colony optimization (ANFIS-ACO). PMID:27611312

Ground truth methods for optical cross-section modeling of biological aerosols

NASA Astrophysics Data System (ADS)

Kalter, J.; Thrush, E.; Santarpia, J.; Chaudhry, Z.; Gilberry, J.; Brown, D. M.; Brown, A.; Carter, C. C.

2011-05-01

Light detection and ranging (LIDAR) systems have demonstrated some capability to meet the needs of a fastresponse standoff biological detection method for simulants in open air conditions. These systems are designed to exploit various cloud signatures, such as differential elastic backscatter, fluorescence, and depolarization in order to detect biological warfare agents (BWAs). However, because the release of BWAs in open air is forbidden, methods must be developed to predict candidate system performance against real agents. In support of such efforts, the Johns Hopkins University Applied Physics Lab (JHU/APL) has developed a modeling approach to predict the optical properties of agent materials from relatively simple, Biosafety Level 3-compatible bench top measurements. JHU/APL has fielded new ground truth instruments (in addition to standard particle sizers, such as the Aerodynamic particle sizer (APS) or GRIMM aerosol monitor (GRIMM)) to more thoroughly characterize the simulant aerosols released in recent field tests at Dugway Proving Ground (DPG). These instruments include the Scanning Mobility Particle Sizer (SMPS), the Ultraviolet Aerodynamic Particle Sizer (UVAPS), and the Aspect Aerosol Size and Shape Analyser (Aspect). The SMPS was employed as a means of measuring smallparticle concentrations for more accurate Mie scattering simulations; the UVAPS, which measures size-resolved fluorescence intensity, was employed as a path toward fluorescence cross section modeling; and the Aspect, which measures particle shape, was employed as a path towards depolarization modeling.

Breaking the Barrier to Slow Water Exchange Rates for Optimal Magnetic Resonance Detection of paraCEST Agents.

PubMed

Fernando, W Shirangi; Martins, André F; Zhao, Piyu; Wu, Yunkou; Kiefer, Garry E; Platas-Iglesias, Carlos; Sherry, A Dean

2016-03-21

EuDOTA-tetraamide complexes as paraCEST agents offer an attractive platform for designing biological sensors and responsive agents. The early versions of these agents showed low sensitivity at temperature and power levels suitable for in vivo applications partly due to non-optimal water exchange rates. Here we report two new EuDOTA derivatives having glutamyl-phosphonate side arms that display the slowest water exchange rates of any other paraCEST agent reported so far. The advantages of such systems are demonstrated experimentally both in vitro and in vivo and DFT calculations were performed to help understand the physical-chemical reasons for this interesting behavior.

Towards the implementation of a spectral database for the detection of biological warfare agents

NASA Astrophysics Data System (ADS)

Carestia, M.; Pizzoferrato, R.; Gelfusa, M.; Cenciarelli, O.; D'Amico, F.; Malizia, A.; Scarpellini, D.; Murari, A.; Vega, J.; Gaudio, P.

2014-10-01

The deliberate use of biological warfare agents (BWA) and other pathogens can jeopardize the safety of population, fauna and flora, and represents a concrete concern from the military and civil perspective. At present, the only commercially available tools for fast warning of a biological attack can perform point detection and require active or passive sampling collection. The development of a stand-off detection system would be extremely valuable to minimize the risk and the possible consequences of the release of biological aerosols in the atmosphere. Biological samples can be analyzed by means of several optical techniques, covering a broad region of the electromagnetic spectrum. Strong evidence proved that the informative content of fluorescence spectra could provide good preliminary discrimination among those agents and it can also be obtained through stand-off measurements. Such a system necessitates a database and a mathematical method for the discrimination of the spectral signatures. In this work, we collected fluorescence emission spectra of the main BWA simulants, to implement a spectral signature database and apply the Universal Multi Event Locator (UMEL) statistical method. Our preliminary analysis, conducted in laboratory conditions with a standard UV lamp source, considers the main experimental setups influencing the fluorescence signature of some of the most commonly used BWA simulants. Our work represents a first step towards the implementation of a spectral database and a laser-based biological stand-off detection and identification technique.

Devices, systems, and methods for conducting sandwich assays using sedimentation

DOEpatents

Schaff, Ulrich Y; Sommer, Gregory J; Singh, Anup K; Hatch, Anson V

2015-02-03

Embodiments of the present invention are directed toward devices, systems, and method for conducting sandwich assays using sedimentation. In one example, a method includes generating complexes on a plurality of beads in a fluid sample, individual ones of the complexes comprising a capture agent, a target analyte, and a labeling agent. The plurality of beads including the complexes may be transported through a density media, wherein the density media has a density lower than a density of the beads and higher than a density of the fluid sample, and wherein the transporting occurs, at least in part, by sedimentation. Signal may be detected from the labeling agents of the complexes.

More About Software for No-Loss Computing

NASA Technical Reports Server (NTRS)

Edmonds, Iarina

2007-01-01

A document presents some additional information on the subject matter of "Integrated Hardware and Software for No- Loss Computing" (NPO-42554), which appears elsewhere in this issue of NASA Tech Briefs. To recapitulate: The hardware and software designs of a developmental parallel computing system are integrated to effectuate a concept of no-loss computing (NLC). The system is designed to reconfigure an application program such that it can be monitored in real time and further reconfigured to continue a computation in the event of failure of one of the computers. The design provides for (1) a distributed class of NLC computation agents, denoted introspection agents, that effects hierarchical detection of anomalies; (2) enhancement of the compiler of the parallel computing system to cause generation of state vectors that can be used to continue a computation in the event of a failure; and (3) activation of a recovery component when an anomaly is detected.

Decentralized Observer with a Consensus Filter for Distributed Discrete-Time Linear Systems

NASA Technical Reports Server (NTRS)

Acikmese, Behcet; Mandic, Milan

2011-01-01

This paper presents a decentralized observer with a consensus filter for the state observation of a discrete-time linear distributed systems. In this setup, each agent in the distributed system has an observer with a model of the plant that utilizes the set of locally available measurements, which may not make the full plant state detectable. This lack of detectability is overcome by utilizing a consensus filter that blends the state estimate of each agent with its neighbors' estimates. We assume that the communication graph is connected for all times as well as the sensing graph. It is proven that the state estimates of the proposed observer asymptotically converge to the actual plant states under arbitrarily changing, but connected, communication and sensing topologies. As a byproduct of this research, we also obtained a result on the location of eigenvalues, the spectrum, of the Laplacian for a family of graphs with self-loops.

Resilient Distributed Estimation Through Adversary Detection

NASA Astrophysics Data System (ADS)

Chen, Yuan; Kar, Soummya; Moura, Jose M. F.

2018-05-01

This paper studies resilient multi-agent distributed estimation of an unknown vector parameter when a subset of the agents is adversarial. We present and analyze a Flag Raising Distributed Estimator ($\\mathcal{FRDE}$) that allows the agents under attack to perform accurate parameter estimation and detect the adversarial agents. The $\\mathcal{FRDE}$ algorithm is a consensus+innovations estimator in which agents combine estimates of neighboring agents (consensus) with local sensing information (innovations). We establish that, under $\\mathcal{FRDE}$, either the uncompromised agents' estimates are almost surely consistent or the uncompromised agents detect compromised agents if and only if the network of uncompromised agents is connected and globally observable. Numerical examples illustrate the performance of $\\mathcal{FRDE}$.

Towards a model of temporal attention for on-line learning in a mobile robot

NASA Astrophysics Data System (ADS)

Marom, Yuval; Hayes, Gillian

2001-06-01

We present a simple attention system, capable of bottom-up signal detection adaptive to subjective internal needs. The system is used by a robotic agent, learning to perform phototaxis and obstacle avoidance by following a teacher agent around a simulated environment, and deciding when to form associations between perceived information and imitated actions. We refer to this kind of decision-making as on-line temporal attention. The main role of the attention system is perception of change; the system is regulated through feedback about cognitive effort. We show how different levels of effort affect both the ability to learn a task, and to execute it.

Nanogels as imaging agents for modalities spanning the electromagnetic spectrum.

PubMed

Chan, Minnie; Almutairi, Adah

2016-01-21

In the past few decades, advances in imaging equipment and protocols have expanded the role of imaging in in vivo diagnosis and disease management, especially in cancer. Traditional imaging agents have rapid clearance and low specificity for disease detection. To improve accuracy in disease identification, localization and assessment, novel nanomaterials are frequently explored as imaging agents to achieve high detection specificity and sensitivity. A promising material for this purpose are hydrogel nanoparticles, whose high hydrophilicity, biocompatibility, and tunable size in the nanometer range make them ideal for imaging. These nanogels (10 to 200 nm) can circumvent uptake by the reticuloendothelial system, allowing longer circulation times than small molecules. In addition, their size/surface properties can be further tailored to optimize their pharmacokinetics for imaging of a particular disease. Herein, we provide a comprehensive review of nanogels as imaging agents in various modalities with sources of signal spanning the electromagnetic spectrum, including MRI, NIR, UV-vis, and PET. Many materials and formulation methods will be reviewed to highlight the versatility of nanogels as imaging agents.

Detection System of the First Rapidly Relocatable Tagged Neutron Inspection System (RRTNIS), Developed in the Framework of the European H2020 C-BORD Project

NASA Astrophysics Data System (ADS)

Fontana, Cristiano Lino; Carnera, Alberto; Lunardon, Marcello; Pino, Felix; Sada, Cinzia; Soramel, Francesca; Stevanato, Luca; Nebbia, Giancarlo; Carasco, Cédric; Perot, Bertrand; Sardet, Alix; Sannie, Guillaume; Iovene, Alessandro; Tintori, Carlo; Grodzicki, Krystian; Moszyński, Marek; Sibczyński, Paweł; Swiderski, Lukasz; Moretto, Sandra

The European project entitled ;effective Container inspection at BORDer control points; (C-BORD) focuses on the development and in-situ tests of a comprehensive cost-effective solution for the generalized Non-Intrusive Inspection (NII) of containers and large-volume freight at the European Union (EU) border. It copes with a large range of targets, including explosives, chemical warfare agents, illicit drugs, tobacco and Special Nuclear Materials. Within the C-BORD project, a new generation of Tagged Neutron Inspection System (TNIS) for cargo containers is foreseen. Unlike its predecessors, this system would be the first Rapidly Relocatable TNIS (RRTNIS). It will be a second-line defense system, to be used on sealed containers in order to detect explosives, illicit drugs and chemical agents in a suspect voxel (elementary volume unit). We report on the status of the RRTNIS system, in particular the overall design, the characterization of the large-volume NaI(Tl) gamma detectors, the digital analysis of the time measurements and the Data Acquisition System (DAQ).

Mouse blood vessel imaging by in-line x-ray phase-contrast imaging

NASA Astrophysics Data System (ADS)

Zhang, Xi; Liu, Xiao-Song; Yang, Xin-Rong; Chen, Shao-Liang; Zhu, Pei-Ping; Yuan, Qing-Xi

2008-10-01

It is virtually impossible to observe blood vessels by conventional x-ray imaging techniques without using contrast agents. In addition, such x-ray systems are typically incapable of detecting vessels with diameters less than 200 µm. Here we show that vessels as small as 30 µm could be detected using in-line phase-contrast x-ray imaging without the use of contrast agents. Image quality was greatly improved by replacing resident blood with physiological saline. Furthermore, an entire branch of the portal vein from the main axial portal vein to the eighth generation of branching could be captured in a single phase-contrast image. Prior to our work, detection of 30 µm diameter blood vessels could only be achieved using x-ray interferometry, which requires sophisticated x-ray optics. Our results thus demonstrate that in-line phase-contrast x-ray imaging, using physiological saline as a contrast agent, provides an alternative to the interferometric method that can be much more easily implemented and also offers the advantage of a larger field of view. A possible application of this methodology is in animal tumor models, where it can be used to observe tumor angiogenesis and the treatment effects of antineoplastic agents.

Development of human cell biosensor system for genotoxicity detection based on DNA damage-induced gene expression.

PubMed

Zager, Valerija; Cemazar, Maja; Hreljac, Irena; Lah, Tamara T; Sersa, Gregor; Filipic, Metka

2010-03-01

Human exposure to genotoxic agents in the environment and everyday life represents a serious health threat. Fast and reliable assessment of genotoxicity of chemicals is of main importance in the fields of new chemicals and drug development as well as in environmental monitoring. The tumor suppressor gene p21, the major downstream target gene of activated p53 which is responsible for cell cycle arrest following DNA damage, has been shown to be specifically up-regulated by genotoxic carcinogens. The aim of our study was to develop a human cell-based biosensor system for simple and fast detection of genotoxic agents. Metabolically active HepG2 human hepatoma cells were transfected with plasmid encoding Enhanced Green Fluorescent Protein (EGFP) under the control of the p21 promoter (p21HepG2GFP). DNA damage was induced by genotoxic agents with known mechanisms of action. The increase in fluorescence intensity, due to p21 mediated EGFP expression, was measured with a fluorescence microplate reader. The viability of treated cells was determined by the colorimetric MTS assay. The directly acting alkylating agent methylmethane sulphonate (MMS) showed significant increase in EGFP production after 48 h at 20 μg/mL. The indirectly acting carcinogen benzo(a)pyren (BaP) and the cross-linking agent cisplatin (CisPt) induced a dose- dependent increase in EGFP fluorescence, which was already significant at concentrations 0.13 μg/mL and 0.41 μg/mL, respectively. Vinblastine (VLB), a spindle poison that does not induce direct DNA damage, induced only a small increase in EGFP fluorescence intensity after 24 h at the lowest concentration (0.1 μg/mL), while exposure to higher concentrations was associated with significantly reduced cell viability. The results of our study demonstrated that this novel assay based on the stably transformed cell line p21HepG2GFP can be used as a fast and simple biosensor system for detection of genetic damage caused by chemical agents.

Detection of Volatile Indicators of Illicit Substances by the Olfactory Receptors of Drosophila melanogaster

PubMed Central

Marshall, Brenton; Warr, Coral G.

2010-01-01

Insects can detect a large range of odors with a numerically simple olfactory system that delivers high sensitivity and accurate discrimination. Therefore, insect olfactory receptors hold great promise as biosensors for detection of volatile organic chemicals in a range of applications. The array of olfactory receptor neurons of Drosophila melanogaster is rapidly becoming the best-characterized natural nose. We have investigated the suitability of Drosophila receptors as detectors for volatiles with applications in law enforcement, emergency response, and security. We first characterized responses of the majority of olfactory neuron types to a set of diagnostic odorants. Being thus able to correctly identify neurons, we then screened for responses from 38 different types of neurons to 35 agents. We identified 13 neuron types with responses to 13 agents. As individual Drosophila receptor genes have been mapped to neuron types, we can infer which genes confer responsiveness to the neurons. The responses were confirmed for one receptor by expressing it in a nonresponsive neuron. The fly olfactory system is mainly adapted to detect volatiles from fermenting fruits. However, our findings establish that volatiles associated with illicit substances, many of which are of nonnatural origin, are also detected by Drosophila receptors. PMID:20530374

Weighted link graphs: a distributed IDS for secondary intrusion detection and defense

NASA Astrophysics Data System (ADS)

Zhou, Mian; Lang, Sheau-Dong

2005-03-01

While a firewall installed at the perimeter of a local network provides the first line of defense against the hackers, many intrusion incidents are the results of successful penetration of the firewalls. One computer"s compromise often put the entire network at risk. In this paper, we propose an IDS that provides a finer control over the internal network. The system focuses on the variations of connection-based behavior of each single computer, and uses a weighted link graph to visualize the overall traffic abnormalities. The functionality of our system is of a distributed personal IDS system that also provides a centralized traffic analysis by graphical visualization. We use a novel weight assignment schema for the local detection within each end agent. The local abnormalities are quantitatively carried out by the node weight and link weight and further sent to the central analyzer to build the weighted link graph. Thus, we distribute the burden of traffic processing and visualization to each agent and make it more efficient for the overall intrusion detection. As the LANs are more vulnerable to inside attacks, our system is designed as a reinforcement to prevent corruption from the inside.

Detection limits of antimicrobials in ewe milk by delvotest photometric measurements.

PubMed

Althaus, R L; Torres, A; Montero, A; Balasch, S; Molina, M P

2003-02-01

The Delvotest method detection limits per manufacturer's instructions at a fixed reading time of 3 h for 24 antimicrobial agents were determined in ewe milk by photometric measurement. For each drug, eight concentrations were tested on 20 ewe milk samples from individual ewes. Detection limits, determined by means of logistic regression models, were (microg/kg): 3, amoxycillin; 2, ampicillin; 18, cloxacillin; 1, penicillin "G"; 34, cefadroxil; 430, cephalosporin "C"; 40, cephalexin; 20, cefoperazone; 33, Ceftiofur; 18, cefuroxime; 6100, streptomycin; 1200, gentamycin; 2600, neomycin; 830, erythromycin; 100, tylosin; 180, doxycycline; 320, oxytetracycline; 590, tetracycline; 88, sulfadiazine; 44, sulfamethoxazole; 140, sulfametoxypyridazine; 48, sulfaquinoxaline; 12,000, chloramphenicol; and 290, trimethoprim. Whereas the beta-lactam antibiotics, sulphonamides, and tylosin were detected by Delvotest method at levels equal to those of maximum residue limits, its sensitivity needs to be enhanced to detect aminoglycosides, tetracyclines, streptomycin, chloramphenicol, and trimethoprim residues in ewe milk or to develop an integrated residue detection system for ewe milk with different sensitive microorganisms for each group of antiinfectious agents.

Proceedings of the Army Science Conference (15th) Held at West Point, New York on 17-19 June 1986. Volume 2. Principal Authors H through L.

DTIC Science & Technology

1986-06-20

Page Leonard, Joseph M. See Seiders, Barbara A. B. V 189 Linden, Carol D. See Canonico, Peter G. 1 127 Little, James S. A Potential Nerve Agent II 271...Semi-Automated System for Testing 11 235 Waring, Paul P. the Efficacy of Nerve Agent Hawkins, George S. Protection/Decontamination Powanda, Michael...potential uses. Among them are: 1) detection of organofluoro- phosphate chemicals, 2) non-corrosive decontamination of nerve agent mate- rials

Current and Developing Technologies for Monitoring Agents of Bioterrorism and Biowarfare

PubMed Central

Lim, Daniel V.; Simpson, Joyce M.; Kearns, Elizabeth A.; Kramer, Marianne F.

2005-01-01

Recent events have made public health officials acutely aware of the importance of rapidly and accurately detecting acts of bioterrorism. Because bioterrorism is difficult to predict or prevent, reliable platforms to rapidly detect and identify biothreat agents are important to minimize the spread of these agents and to protect the public health. These platforms must not only be sensitive and specific, but must also be able to accurately detect a variety of pathogens, including modified or previously uncharacterized agents, directly from complex sample matrices. Various commercial tests utilizing biochemical, immunological, nucleic acid, and bioluminescence procedures are currently available to identify biological threat agents. Newer tests have also been developed to identify such agents using aptamers, biochips, evanescent wave biosensors, cantilevers, living cells, and other innovative technologies. This review describes these current and developing technologies and considers challenges to rapid, accurate detection of biothreat agents. Although there is no ideal platform, many of these technologies have proved invaluable for the detection and identification of biothreat agents. PMID:16223949

29 CFR 1926.903 - Underground transportation of explosives.

Code of Federal Regulations, 2012 CFR

2012-07-01

...) Trucks used for the transportation of explosives underground shall have the electrical system checked weekly to detect any failures which may constitute an electrical hazard. A certification record which... powered by the truck's electrical system, shall be prohibited. (g) Explosives and blasting agents shall be...

29 CFR 1926.903 - Underground transportation of explosives.

Code of Federal Regulations, 2014 CFR

2014-07-01

...) Trucks used for the transportation of explosives underground shall have the electrical system checked weekly to detect any failures which may constitute an electrical hazard. A certification record which... powered by the truck's electrical system, shall be prohibited. (g) Explosives and blasting agents shall be...

29 CFR 1926.903 - Underground transportation of explosives.

Code of Federal Regulations, 2013 CFR

2013-07-01

...) Trucks used for the transportation of explosives underground shall have the electrical system checked weekly to detect any failures which may constitute an electrical hazard. A certification record which... powered by the truck's electrical system, shall be prohibited. (g) Explosives and blasting agents shall be...

29 CFR 1926.903 - Underground transportation of explosives.

Code of Federal Regulations, 2011 CFR

2011-07-01

...) Trucks used for the transportation of explosives underground shall have the electrical system checked weekly to detect any failures which may constitute an electrical hazard. A certification record which... powered by the truck's electrical system, shall be prohibited. (g) Explosives and blasting agents shall be...

29 CFR 1926.903 - Underground transportation of explosives.

Code of Federal Regulations, 2010 CFR

2010-07-01

...) Trucks used for the transportation of explosives underground shall have the electrical system checked weekly to detect any failures which may constitute an electrical hazard. A certification record which... powered by the truck's electrical system, shall be prohibited. (g) Explosives and blasting agents shall be...

Loop-mediated isothermal amplification as an emerging technology for detection of Yersinia ruckeri the causative agent of enteric red mouth disease in fish.

PubMed

Saleh, Mona; Soliman, Hatem; El-Matbouli, Mansour

2008-08-12

Enteric Redmouth (ERM) disease also known as Yersiniosis is a contagious disease affecting salmonids, mainly rainbow trout. The causative agent is the gram-negative bacterium Yersinia ruckeri. The disease can be diagnosed by isolation and identification of the causative agent, or detection of the Pathogen using fluorescent antibody tests, ELISA and PCR assays. These diagnostic methods are laborious, time consuming and need well trained personnel. A loop-mediated isothermal amplification (LAMP) assay was developed and evaluated for detection of Y. ruckeri the etiological agent of enteric red mouth (ERM) disease in salmonids. The assay was optimised to amplify the yruI/yruR gene, which encodes Y. ruckeri quorum sensing system, in the presence of a specific primer set and Bst DNA polymerase at an isothermal temperature of 63 degrees C for one hour. Amplification products were detected by visual inspection, agarose gel electrophoresis and by real-time monitoring of turbidity resulted by formation of LAMP amplicons. Digestion with HphI restriction enzyme demonstrated that the amplified product was unique. The specificity of the assay was verified by the absence of amplification products when tested against related bacteria. The assay had 10-fold higher sensitivity compared with conventional PCR and successfully detected Y. ruckeri not only in pure bacterial culture but also in tissue homogenates of infected fish. The ERM-LAMP assay represents a practical alternative to the microbiological approach for rapid, sensitive and specific detection of Y. ruckeri in fish farms. The assay is carried out in one hour and needs only a heating block or water bath as laboratory furniture. The advantages of the ERM-LAMP assay make it a promising tool for molecular detection of enteric red mouth disease in fish farms.

Biosensor platform based on carbon nanotubes covalently modified with aptamers

NASA Astrophysics Data System (ADS)

Komarov, I. A.; Rubtsova, E. I.; Golovin, A. V.; Bobrinetskiy, I. I.

2016-12-01

We developed a new platform for biosensing applications. Aptamers as sensitive agents have a great potential and gives us possibility to have highest possible selectivity among other sensing agents like enzymes or antibodies. We covalently bound aptamers to the functional groups of c-CNTs and then put this system on the surface of polymer substrate. Thus we got high sensitive flexible transparent biological sensors. We also suggest that by varying aptamer type we can make set of biosensors for disease detection which can be integrated into self-healthcare systems and gadgets.

Adaptive Neuro-Fuzzy Determination of the Effect of Experimental Parameters on Vehicle Agent Speed Relative to Vehicle Intruder.

PubMed

Shamshirband, Shahaboddin; Banjanovic-Mehmedovic, Lejla; Bosankic, Ivan; Kasapovic, Suad; Abdul Wahab, Ainuddin Wahid Bin

2016-01-01

Intelligent Transportation Systems rely on understanding, predicting and affecting the interactions between vehicles. The goal of this paper is to choose a small subset from the larger set so that the resulting regression model is simple, yet have good predictive ability for Vehicle agent speed relative to Vehicle intruder. The method of ANFIS (adaptive neuro fuzzy inference system) was applied to the data resulting from these measurements. The ANFIS process for variable selection was implemented in order to detect the predominant variables affecting the prediction of agent speed relative to intruder. This process includes several ways to discover a subset of the total set of recorded parameters, showing good predictive capability. The ANFIS network was used to perform a variable search. Then, it was used to determine how 9 parameters (Intruder Front sensors active (boolean), Intruder Rear sensors active (boolean), Agent Front sensors active (boolean), Agent Rear sensors active (boolean), RSSI signal intensity/strength (integer), Elapsed time (in seconds), Distance between Agent and Intruder (m), Angle of Agent relative to Intruder (angle between vehicles °), Altitude difference between Agent and Intruder (m)) influence prediction of agent speed relative to intruder. The results indicated that distance between Vehicle agent and Vehicle intruder (m) and angle of Vehicle agent relative to Vehicle Intruder (angle between vehicles °) is the most influential parameters to Vehicle agent speed relative to Vehicle intruder.

The role of ion optics modeling in the design and development of ion mobility spectrometers

NASA Astrophysics Data System (ADS)

Griffin, Matthew T.

2005-05-01

Detection of trace gases by ion mobility spectroscopy (IMS) has become common in recent years. In fact, IMS devices are the most commonly deployed military devices for the detection of classical chemical warfare agents (CWA). IMS devices are protecting the homeland by aiding first responders in the identification of toxic industrial chemicals (TICs) and providing explosive and narcotic screening systems. Spurred by the asymmetric threat posed by new threat agents and the ever expanding list of toxic chemicals, research in the development, improvement, and optimization of IMS systems has increased. Much of the research is focused on increasing the sensitivity and selectivity of IMS systems. Ion optics is a large area of study in the field of mass spectrometry, but has been mostly overlooked in the design and development of IMS systems. Ion optics provides insight into particle trajectories, duty cycle, and efficiency of these systems. This paper will outline the role that ion optics can have in the development of IMS systems and introduce the trade space for traditional IMS as well as differential mobility spectroscopy.

Instrument response measurements of ion mobility spectrometers in situ: maintaining optimal system performance of fielded systems

NASA Astrophysics Data System (ADS)

Wallis, Eric; Griffin, Todd M.; Popkie, Norm, Jr.; Eagan, Michael A.; McAtee, Robert F.; Vrazel, Danet; McKinly, Jim

2005-05-01

Ion Mobility Spectroscopy (IMS) is the most widespread detection technique in use by the military for the detection of chemical warfare agents, explosives, and other threat agents. Moreover, its role in homeland security and force protection has expanded due, in part, to its good sensitivity, low power, lightweight, and reasonable cost. With the increased use of IMS systems as continuous monitors, it becomes necessary to develop tools and methodologies to ensure optimal performance over a wide range of conditions and extended periods of time. Namely, instrument calibration is needed to ensure proper sensitivity and to correct for matrix or environmental effects. We have developed methodologies to deal with the semi-quantitative nature of IMS and allow us to generate response curves that allow a gauge of instrument performance and maintenance requirements. This instrumentation communicates to the IMS systems via a software interface that was developed in-house. The software measures system response, logs information to a database, and generates the response curves. This paper will discuss the instrumentation, software, data collected, and initial results from fielded systems.

Direct sampling of chemical weapons in water by photoionization mass spectrometry.

PubMed

Syage, Jack A; Cai, Sheng-Suan; Li, Jianwei; Evans, Matthew D

2006-05-01

The vulnerability of water supplies to toxic contamination calls for fast and effective means for screening water samples for multiple threats. We describe the use of photoionization (PI) mass spectrometry (MS) for high-speed, high-throughput screening and molecular identification of chemical weapons (CW) threats and other hazardous compounds. The screening technology can detect a wide range of compounds at subacute concentrations with no sample preparation and a sampling cycle time of approximately 45 s. The technology was tested with CW agents VX, GA, GB, GD, GF, HD, HN1, and HN3, in addition to riot agents and precursors. All are sensitively detected and give simple PI mass spectra dominated by the parent ion. The target application of the PI MS method is as a routine, real-time early warning system for CW agents and other hazardous compounds in air and in water. In this work, we also present comprehensive measurements for water analysis and report on the system detection limits, linearity, quantitation accuracy, and false positive (FP) and false negative rates for concentrations at subacute levels. The latter data are presented in the form of receiver operating characteristic curves of the form of detection probability P(D) versus FP probability P(FP). These measurements were made using the CW surrogate compounds, DMMP, DEMP, DEEP, and DIMP. Method detection limits (3sigma) obtained using a capillary injection method yielded 1, 6, 3, and 2 ng/mL, respectively. These results were obtained using 1-microL injections of water samples without any preparation, corresponding to mass detection limits of 1, 6, 3, and 2 pg, respectively. The linear range was about 3-4 decades and the dynamic range about 4-5 decades. The relative standard deviations were generally <10% at CW subacute concentrations levels.

Multispectral photoacoustic tomography for detection of small tumors inside biological tissues

NASA Astrophysics Data System (ADS)

Hirasawa, Takeshi; Okawa, Shinpei; Tsujita, Kazuhiro; Kushibiki, Toshihiro; Fujita, Masanori; Urano, Yasuteru; Ishihara, Miya

2018-02-01

Visualization of small tumors inside biological tissue is important in cancer treatment because that promotes accurate surgical resection and enables therapeutic effect monitoring. For sensitive detection of tumor, we have been developing photoacoustic (PA) imaging technique to visualize tumor-specific contrast agents, and have already succeeded to image a subcutaneous tumor of a mouse using the contrast agents. To image tumors inside biological tissues, extension of imaging depth and improvement of sensitivity were required. In this study, to extend imaging depth, we developed a PA tomography (PAT) system that can image entire cross section of mice. To improve sensitivity, we discussed the use of the P(VDF-TrFE) linear array acoustic sensor that can detect PA signals with wide ranges of frequencies. Because PA signals produced from low absorbance optical absorbers shifts to low frequency, we hypothesized that the detection of low frequency PA signals improves sensitivity to low absorbance optical absorbers. We developed a PAT system with both a PZT linear array acoustic sensor and the P(VDF-TrFE) sensor, and performed experiment using tissue-mimicking phantoms to evaluate lower detection limits of absorbance. As a result, PAT images calculated from low frequency components of PA signals detected by the P(VDF-TrFE) sensor could visualize optical absorbers with lower absorbance.

[Contrast medium enhanced magnetic resonance tomography of liver metastases: positive versus negative contrast media].

PubMed

Hammerstingl, R M; Schwarz, W; Hochmuth, K; Staib-Sebler, E; Lorenz, M; Vogl, T J

2001-01-01

The development in oncologic liver surgery as well as modified interventional therapy strategies of the liver have resulted in improved diagnostic imaging. The evolution of contrast agents for MR imaging of the liver has proceeded along several different paths with the common goal of improving liver-lesion contrast. In MRI contrast agents act indirectly by their effects on relaxation times. Contrast agents used for hepatic MR imaging can be categorized in those that target the extracellular space, the hepatobiliary system, and the reticuloendothelial system. The first two result in a positive enhancement, the last one in a negative enhancement. Positive enhancers allow a better characterization of liver metastases using dynamic sequence protocols. Detection rate of liver metastases is increased using hepatobiliary contrast-enhanced MRI compared to unenhanced MRI. Negative enhancers, iron oxide particles, significantly increase tumor-to-liver contrast and allow detection of more lesions than other diagnostic methods. Iron-oxide enhanced MRI enables differential diagnosis of liver metastases comparing morphologic features using T2 and T1-weighted sequences.

Chemically-functionalized microcantilevers for detection of chemical, biological and explosive material

DOEpatents

Pinnaduwage, Lal A [Knoxville, TN; Thundat, Thomas G [Knoxville, TN; Brown, Gilbert M [Knoxville, TN; Hawk, John Eric [Olive Branch, MS; Boiadjiev, Vassil I [Knoxville, TN

2007-04-24

A chemically functionalized cantilever system has a cantilever coated on one side thereof with a reagent or biological species which binds to an analyte. The system is of particular value when the analyte is a toxic chemical biological warfare agent or an explosive.

EVALUATION OF SENSOR AND MONITORS TO DETECT CHANGES IN WATER QUALITY

EPA Science Inventory

The safety and security of distribution systems has come under reassessment in the past year. Several chemical and biological agents have been identified that might constitute a credible threat against water supply systems. There have also been a few reported threats against wate...

Surface with two paint strips for detection and warning of chemical warfare and radiological agents

DOEpatents

Farmer, Joseph C.

2013-04-02

A system for warning of corrosion, chemical, or radiological substances. The system comprises painting a surface with a paint or coating that includes an indicator material and monitoring the surface for indications of the corrosion, chemical, or radiological substances.

Pharmacological validation of individual animal locomotion, temperature and behavioural analysis in group-housed rats using a novel automated home cage analysis system: A comparison with the modified Irwin test.

PubMed

Tse, Karen; Sillito, Rowland; Keerie, Amy; Collier, Rachel; Grant, Claire; Karp, Natasha A; Vickers, Cathy; Chapman, Kathryn; Armstrong, J Douglas; Redfern, William S

2018-04-01

The ActualHCA™ system continuously monitors the activity, temperature and behavior of group-housed rats without invasive surgery. The system was validated to detect the contrasting effects of sedative and stimulant test agents (chlorpromazine, clonidine and amphetamine), and compared with the modified Irwin test (mIT) with rectal temperature measurements. Six male Han Wistar rats per group were used to assess each test agent and vehicle controls in separate ActualHCA™ recordings and mIT. The mIT was undertaken at 15, 30 mins, 1, 2, 4 and 24 h post-dose. ActualHCA™ recorded continuously for 24 h post-dose under 3 experimental conditions: dosed during light phase, dark phase, and light phase with a scheduled cage change at the time of peak effects determined by mIT. ActualHCA™ detected an increase stimulated activity from the cage change at 1-2 h post-dose which was obliterated by chlorpromazine and clonidine. Amphetamine increased activity up to 4 h post-dose in all conditions. Temperature from ActualHCA™ was affected by all test agents in all conditions. The mIT showed effects on all 3 test agents up to 4 h post-dose, with maximal effects at 1-2 h post-dose. The maximal effects on temperature from ActualHCA™ differed from mIT. Delayed effects on activity were detected by ActualHCA™, but not on mIT. Continuous monitoring has the advantage of capturing effects over time that may be missed with manual tests using pre-determined time points. This automated behavioural system does not replace the need for conventional methods but could be implemented simultaneously to improve our understanding of behavioural pharmacology. Copyright © 2018 Elsevier Inc. All rights reserved.

Adjustably Autonomous Multi-agent Plan Execution with an Internal Spacecraft Free-Flying Robot Prototype

NASA Technical Reports Server (NTRS)

Dorais, Gregory A.; Nicewarner, Keith

2006-01-01

We present an multi-agent model-based autonomy architecture with monitoring, planning, diagnosis, and execution elements. We discuss an internal spacecraft free-flying robot prototype controlled by an implementation of this architecture and a ground test facility used for development. In addition, we discuss a simplified environment control life support system for the spacecraft domain also controlled by an implementation of this architecture. We discuss adjustable autonomy and how it applies to this architecture. We describe an interface that provides the user situation awareness of both autonomous systems and enables the user to dynamically edit the plans prior to and during execution as well as control these agents at various levels of autonomy. This interface also permits the agents to query the user or request the user to perform tasks to help achieve the commanded goals. We conclude by describing a scenario where these two agents and a human interact to cooperatively detect, diagnose and recover from a simulated spacecraft fault.

Design, Implementation and Case Study of WISEMAN: WIreless Sensors Employing Mobile AgeNts

NASA Astrophysics Data System (ADS)

González-Valenzuela, Sergio; Chen, Min; Leung, Victor C. M.

We describe the practical implementation of Wiseman: our proposed scheme for running mobile agents in Wireless Sensor Networks. Wiseman’s architecture derives from a much earlier agent system originally conceived for distributed process coordination in wired networks. Given the memory constraints associated with small sensor devices, we revised the architecture of the original agent system to make it applicable to this type of networks. Agents are programmed as compact text scripts that are interpreted at the sensor nodes. Wiseman is currently implemented in TinyOS ver. 1, its binary image occupies 19Kbytes of ROM memory, and it occupies 3Kbytes of RAM to operate. We describe the rationale behind Wiseman’s interpreter architecture and unique programming features that can help reduce packet overhead in sensor networks. In addition, we gauge the proposed system’s efficiency in terms of task duration with different network topologies through a case study that involves an early-fire-detection application in a fictitious forest setting.

Detection of disease outbreaks by the use of oral manifestations.

PubMed

Torres-Urquidy, M H; Wallstrom, G; Schleyer, T K L

2009-01-01

Oral manifestations of diseases caused by bioterrorist agents could be a potential data source for biosurveillance. This study had the objectives of determining the oral manifestations of diseases caused by bioterrorist agents, measuring the prevalence of these manifestations in emergency department reports, and constructing and evaluating a detection algorithm based on them. We developed a software application to detect oral manifestations in free text and identified positive reports over three years of data. The normal frequency in reports for oral manifestations related to anthrax (including buccal ulcers-sore throat) was 7.46%. The frequency for tularemia was 6.91%. For botulism and smallpox, the frequencies were 0.55% and 0.23%. We simulated outbreaks for these bioterrorism diseases and evaluated the performance of our system. The detection algorithm performed better for smallpox and botulism than for anthrax and tularemia. We found that oral manifestations can be a valuable tool for biosurveillance.

Adaptive Remote-Sensing Techniques Implementing Swarms of Mobile Agents

DOE Office of Scientific and Technical Information (OSTI.GOV)

Asher, R.B.; Cameron, S.M.; Loubriel, G.M.

1998-11-25

In many situations, stand-off remote-sensing and hazard-interdiction techniques over realistic operational areas are often impractical "and difficult to characterize. An alternative approach is to implement an adap- tively deployable array of sensitive agent-specific devices. Our group has been studying the collective be- havior of an autonomous, multi-agent system applied to chedbio detection and related emerging threat applications, The current physics-based models we are using coordinate a sensor array for mukivanate sig- nal optimization and coverage as re,alized by a swarm of robots or mobile vehicles. These intelligent control systems integrate'glob"ally operating decision-making systems and locally cooperative learning neural net- worksmore » to enhance re+-timp operational responses to dynarnical environments examples of which include obstacle avoidance, res~onding to prevailing wind patterns, and overcoming other natural obscurants or in- terferences. Collectively',tkensor nefirons with simple properties, interacting according to basic community rules, can accomplish complex interconnecting functions such as generalization, error correction, pattern recognition, sensor fusion, and localization. Neural nets provide a greater degree of robusmess and fault tolerance than conventional systems in that minor variations or imperfections do not impair performance. The robotic platforms would be equipped with sensor devices that perform opticaI detection of biologicais in combination with multivariate chemical analysis tools based on genetic and neural network algorithms, laser-diode LIDAR analysis, ultra-wideband short-pulsed transmitting and receiving antennas, thermal im- a:ing sensors, and optical Communication technology providing robust data throughput pathways. Mission scenarios under consideration include ground penetrating radar (GPR) for detection of underground struc- tures, airborne systems, and plume migration and mitigation. We will describe our research in these areas anti give a status report on our progress.« less

Detection of cucumber green mottle mosaic virus-infected watermelon seeds using short wave infrared (SWIR) hyperspectral imaging system

USDA-ARS?s Scientific Manuscript database

The cucurbit diseases caused by cucumber green mottle mosaic virus (CGMMV) have led to a serious problem to growers and seed producers because it is difficult to prevent spreading through causal agent of seeds. Conventional detection methods for infected seed such as a biological, serological, and m...

Peptide-based protein capture agents with high affinity, selectivity, and stability as antibody replacements in biodetection assays

NASA Astrophysics Data System (ADS)

Coppock, Matthew B.; Farrow, Blake; Warner, Candice; Finch, Amethist S.; Lai, Bert; Sarkes, Deborah A.; Heath, James R.; Stratis-Cullum, Dimitra

2014-05-01

Current biodetection assays that employ monoclonal antibodies as primary capture agents exhibit limited fieldability, shelf life, and performance due to batch-to-batch production variability and restricted thermal stability. In order to improve upon the detection of biological threats in fieldable assays and systems for the Army, we are investigating protein catalyzed capture (PCC) agents as drop-in replacements for the existing antibody technology through iterative in situ click chemistry. The PCC agent oligopeptides are developed against known protein epitopes and can be mass produced using robotic methods. In this work, a PCC agent under development will be discussed. The performance, including affinity, selectivity, and stability of the capture agent technology, is analyzed by immunoprecipitation, western blotting, and ELISA experiments. The oligopeptide demonstrates superb selectivity coupled with high affinity through multi-ligand design, and improved thermal, chemical, and biochemical stability due to non-natural amino acid PCC agent design.

[EXPERIENCE OF STUDY AND POSSIBLE WAYS OF ELIMINATION OF FALSE POSITIVE AND FALSE NEGATIVE RESULTS DURING EXECUTION OF POLYMERASE CHAIN REACTION ON AN EXAMPLE OF JUNIN VIRUS RNA DETECTION].

PubMed

Sizikova, T E; Lebedev, V N; Pantyukhov, V B; Borisevich, S V; Merkulov, V A

2015-01-01

Experience of study and possible ways of elimination of false positive and false negative results during execution of polymerase chain reaction on an example of Junin virus RNA detection. MATERIALSS AND METHODS: Junin virus--causative agent of Argentine hemorrhagic fever (AHF) strain XJpR37/5787 was obtained from the State collection of pathogenicity group I causative agents of the 48th Central Research Institute. Reagent kit for detection of Junin virus RNA by RT-PCR was developed in the Institute and consists of 4 sets: for isolation of RNA, execution of reverse-transcription reaction, execution of PCR and electrophoretic detection of PCR products. RT-PCR was carried out by a standard technique. Continuous cell cultures of African green monkey Vero B, GMK-AH-1(D) were obtained from the museum of cell culture department of the Centre. An experimental study of the effect of various factors of impact on the sample under investigation ("thawing-freezing", presence of formaldehyde, heparin) on the obtaining of false negative results during Junin virus RNA detection by using RT-PCR was studied. Addition of 0.01% heparin to the samples was shown to completely inhibit PCR. Addition of 0.05% formaldehyde significantly reduces sensitivity of the method. A possibility of reduction of analysis timeframe from 15 to 5 days was shown during detection of the causative agent in samples with low concentration of the latter by growing the samples and subsequent analysis of the material obtained by using RT-PCR. During detection of causative agent by using RT-PCR false negative results could appear in the presence of formaldehyde and heparin in the sample. A possibility of elimination of false negative PCR results due to concentration of the causative agent in the sample under investigation at a level below sensitivity threshold was shown on the example of Junin virus RNA detection by using growing of the pathogen in appropriate accumulation system with subsequent analysis of the material obtained using PCR.

Explanation-aware computing of the prognosis for breast cancer supported by IK-DCBRC: Technical innovation.

PubMed

Khelassi, Abdeldjalil

2014-01-01

Active research is being conducted to determine the prognosis for breast cancer. However, the uncertainty is a major obstacle in this domain of medical research. In that context, explanation-aware computing has the potential for providing meaningful interactions between complex medical applications and users, which would ensure a significant reduction of uncertainty and risks. This paper presents an explanation-aware agent, supported by Intensive Knowledge-Distributed Case-Based Reasoning Classifier (IK-DCBRC), to reduce the uncertainty and risks associated with the diagnosis of breast cancer. A meaningful explanation is generated by inferring from a rule-based system according to the level of abstraction and the reasoning traces. The computer-aided detection is conducted by IK-DCBRC, which is a multi-agent system that applies the case-based reasoning paradigm and a fuzzy similarity function for the automatic prognosis by the class of breast tumors, i.e. malignant or benign, from a pattern of cytological images. A meaningful interaction between the physician and the computer-aided diagnosis system, IK-DCBRC, is achieved via an intelligent agent. The physician can observe the trace of reasoning, terms, justifications, and the strategy to be used to decrease the risks and doubts associated with the automatic diagnosis. The capability of the system we have developed was proven by an example in which conflicts were clarified and transparency was ensured. The explanation agent ensures the transparency of the automatic diagnosis of breast cancer supported by IK-DCBRC, which decreases uncertainty and risks and detects some conflicts.

Detection and isolation of nucleic acid sequences using competitive hybridization probes

DOEpatents

Lucas, Joe N.; Straume, Tore; Bogen, Kenneth T.

1997-01-01

A method for detecting a target nucleic acid sequence in a sample is provided using hybridization probes which competitively hybridize to a target nucleic acid. According to the method, a target nucleic acid sequence is hybridized to first and second hybridization probes which are complementary to overlapping portions of the target nucleic acid sequence, the first hybridization probe including a first complexing agent capable of forming a binding pair with a second complexing agent and the second hybridization probe including a detectable marker. The first complexing agent attached to the first hybridization probe is contacted with a second complexing agent, the second complexing agent being attached to a solid support such that when the first and second complexing agents are attached, target nucleic acid sequences hybridized to the first hybridization probe become immobilized on to the solid support. The immobilized target nucleic acids are then separated and detected by detecting the detectable marker attached to the second hybridization probe. A kit for performing the method is also provided.

Detection and isolation of nucleic acid sequences using competitive hybridization probes

DOEpatents

Lucas, J.N.; Straume, T.; Bogen, K.T.

1997-04-01

A method for detecting a target nucleic acid sequence in a sample is provided using hybridization probes which competitively hybridize to a target nucleic acid. According to the method, a target nucleic acid sequence is hybridized to first and second hybridization probes which are complementary to overlapping portions of the target nucleic acid sequence, the first hybridization probe including a first complexing agent capable of forming a binding pair with a second complexing agent and the second hybridization probe including a detectable marker. The first complexing agent attached to the first hybridization probe is contacted with a second complexing agent, the second complexing agent being attached to a solid support such that when the first and second complexing agents are attached, target nucleic acid sequences hybridized to the first hybridization probe become immobilized on to the solid support. The immobilized target nucleic acids are then separated and detected by detecting the detectable marker attached to the second hybridization probe. A kit for performing the method is also provided. 7 figs.

Detection of Alkylating Agents using Electrical and Mechanical Means

NASA Astrophysics Data System (ADS)

Gerchikov, Yulia; Borzin, Elena; Gannot, Yair; Shemesh, Ariel; Meltzman, Shai; Hertzog-Ronen, Carmit; Tal, Shay; Stolyarova, Sara; Nemirovsky, Yael; Tessler, Nir; Eichen, Yoav

2011-08-01

Alkylating agents are reactive molecules having at least one polar bond between a carbon atom and a good leaving group. These often simple molecules are frequently used in organic synthesis, as sterilizing agents in agriculture and even as anticancer agents in medicine. Unfortunately, for over a century, some of the highly reactive alkylating agents are also being used as blister chemical warfare agents. Being relatively simple to make, the risk is that these will be applied by terrorists as poor people warfare agents. The detection and identification of such alkylating agents is not a simple task because of their high reactivity and simple structure of the reactive site. Here we report on new approaches to the detection and identification of such alkylating agents using electrical (organic field effect transistors) and mechanical (microcantilevers) means.

Surface-enhanced Raman as a water monitor for warfare agents

NASA Astrophysics Data System (ADS)

Spencer, Kevin M.; Sylvia, James M.; Clauson, Susan L.; Janni, James A.

2002-02-01

The threat of chemical warfare agents being released upon civilian and military personnel continues to escalate. One aspect of chemical preparedness is to analyze and protect the portable water supply for the military. Chemical nerve, blister, and choking agents, as well as biological threats must all be analyzed and low limits of detection must be verified. For chemical agents, this generally means detection down to the low ppb levels. Surface-Enhanced Raman Spectroscopy (SERS) is a spectroscopic technique that can detect trace levels of contaminants directly in the aqueous environment. In this paper, results are presented on the use of SERS to detect chemical and biological agent simulants with an end goal of creating a Joint Service Agent Water Monitor. Detection of cyanide, 2-chloroethyl ethyl sulfide, phosphonates, Gram-positive and Gram-negative bacteria using SERS has been performed and is discussed herein. Aspects of transferring laboratory results to an unattended field instrument are also discussed.

Fluorescence/depolarization lidar for mid-range stand-off detection of biological agents

NASA Astrophysics Data System (ADS)

Mierczyk, Z.; Kopczyński, K.; Zygmunt, M.; Wojtanowski, J.; Młynczak, J.; Gawlikowski, A.; Młodzianko, A.; Piotrowski, W.; Gietka, A.; Knysak, P.; Drozd, T.; Muzal, M.; Kaszczuk, M.; Ostrowski, R.; Jakubaszek, M.

2011-06-01

LIDAR system for real-time standoff detection of bio-agents is presented and preliminary experimental results are discussed. The detection approach is based on two independent physical phenomena: (1) laser induced fluorescence (LIF), (2) depolarization resulting from elastic scattering on non-spherical particles. The device includes three laser sources, two receiving telescopes, depolarization component and spectral signature analyzing spectrograph. It was designed to provide the stand-off detection capability at ranges from 200 m up to several kilometers. The system as a whole forms a mobile platform for vehicle or building installation. Additionally, it's combined with a scanning mechanics and advanced software, which enable to conduct the semi-automatic monitoring of a specified space sector. For fluorescence excitation, 3-rd (355 nm) and 4-th (266 nm) harmonics of Nd:YAG pulsed lasers are used. They emit short (~6 ns) pulses with the repetition rate of 20 Hz. Collecting optics for fluorescence echo detection and spectral content analysis includes 25 mm diameter f/4 Newton telescope, Czerny Turner spectrograph and 32-channel PMT. Depending on the grating applied, the spectral resolution from 20 nm up to 3 nm per channel can be achieved. The system is also equipped with an eye-safe (1.5 μm) Nd:YAG OPO laser for elastic backscattering/depolarization detection. The optical echo signal is collected by Cassegrain telescope with aperture diameter of 12.5 mm. Depolarization detection component based on polarizing beam-splitter serves as the stand-off particle-shape analyzer, which is very valuable in case of non-spherical bio-aerosols sensing.

Emerging Gram negative resistance to last-line antimicrobial agents fosfomycin, colistin and ceftazidime-avibactam - epidemiology, laboratory detection and treatment implications.

PubMed

Sherry, Norelle; Howden, Benjamin

2018-04-01

Multidrug-resistant (MDR) and extensively-drug-resistant (XDR) Gram-negative bacteria have emerged as a major threat to human health globally. This has resulted in the 're-discovery' of some older antimicrobials and development of new agents, however resistance has also rapidly emerged to these agents. Areas covered: Here we describe recent developments in resistance to three of the most important last-line antimicrobials for treatment of MDR and XDR Gram negatives: fosfomycin, colistin and ceftazidime-avibactam. Expert commentary: A key challenge for microbiologists and clinicians using these agents for treating patients with MDR and XDR Gram negative infections is the need to ensure appropriate reference methods are being used to test susceptibility to these agents, especially colistin and fosfomycin. These methods are not available in all laboratories meaning accurate results are either delayed, or potentially inaccurate as non-reference methods are employed. Combination therapy for MDR and XDR Gram negatives is likely to become more common, and future studies should focus on the clinical effects of monotherapy vs combination therapy, as well as validation of synergy testing methods. Effective national and international surveillance systems to detect and respond to resistance to these last line agents are also critical.

Toxicology of organophosphorus compounds in view of an increasing terrorist threat.

PubMed

Worek, Franz; Wille, Timo; Koller, Marianne; Thiermann, Horst

2016-09-01

The implementation of the Chemical Weapon Convention (CWC), prohibiting the development, production, storage and use of chemical weapons by 192 nations and the ban of highly toxic OP pesticides, especially class I pesticides according to the WHO classification, by many countries constitutes a great success of the international community. However, the increased interest of terrorist groups in toxic chemicals and chemical warfare agents presents new challenges to our societies. Almost seven decades of research on organophosphorus compound (OP) toxicology was mainly focused on a small number of OP nerve agents despite the fact that a huge number of OP analogues, many of these agents having comparable toxicity to classical nerve agents, were synthesized and published. Only limited physicochemical, toxicological and medical information on nerve agent analogues is available in the open literature. This implies potential gaps of our capabilities to detect, to decontaminate and to treat patients if nerve agent analogues are disseminated and may result in inadequate effectiveness of newly developed countermeasures. In summary, our societies may face new, up to now disregarded, threats by toxic OP which calls for increased awareness and appropriate preparedness of military and civilian CBRN defense, a broader approach for new physical and medical countermeasures and an integrated system of effective detection, decontamination, physical protection and treatment.

Lessons Learned from Autonomous Sciencecraft Experiment

NASA Technical Reports Server (NTRS)

Chien, Steve A.; Sherwood, Rob; Tran, Daniel; Cichy, Benjamin; Rabideau, Gregg; Castano, Rebecca; Davies, Ashley; Mandl, Dan; Frye, Stuart; Trout, Bruce;

Oral Administration and Detection of a Near-Infrared Molecular Imaging Agent in an Orthotopic Mouse Model for Breast Cancer Screening

PubMed Central

2018-01-01

Molecular imaging is advantageous for screening diseases such as breast cancer by providing precise spatial information on disease-associated biomarkers, something neither blood tests nor anatomical imaging can achieve. However, the high cost and risks of ionizing radiation for several molecular imaging modalities have prevented a feasible and scalable approach for screening. Clinical studies have demonstrated the ability to detect breast tumors using nonspecific probes such as indocyanine green, but the lack of molecular information and required intravenous contrast agent does not provide a significant benefit over current noninvasive imaging techniques. Here we demonstrate that negatively charged sulfate groups, commonly used to improve solubility of near-infrared fluorophores, enable sufficient oral absorption and targeting of fluorescent molecular imaging agents for completely noninvasive detection of diseased tissue such as breast cancer. These functional groups improve the pharmacokinetic properties of affinity ligands to achieve targeting efficiencies compatible with clinical imaging devices using safe, nonionizing radiation (near-infrared light). Together, this enables development of a “disease screening pill” capable of oral absorption and systemic availability, target binding, background clearance, and imaging at clinically relevant depths for breast cancer screening. This approach should be adaptable to other molecular targets and diseases for use as a new class of screening agents. PMID:29696981

Oral Administration and Detection of a Near-Infrared Molecular Imaging Agent in an Orthotopic Mouse Model for Breast Cancer Screening.

PubMed

Bhatnagar, Sumit; Verma, Kirti Dhingra; Hu, Yongjun; Khera, Eshita; Priluck, Aaron; Smith, David E; Thurber, Greg M

2018-05-07

Molecular imaging is advantageous for screening diseases such as breast cancer by providing precise spatial information on disease-associated biomarkers, something neither blood tests nor anatomical imaging can achieve. However, the high cost and risks of ionizing radiation for several molecular imaging modalities have prevented a feasible and scalable approach for screening. Clinical studies have demonstrated the ability to detect breast tumors using nonspecific probes such as indocyanine green, but the lack of molecular information and required intravenous contrast agent does not provide a significant benefit over current noninvasive imaging techniques. Here we demonstrate that negatively charged sulfate groups, commonly used to improve solubility of near-infrared fluorophores, enable sufficient oral absorption and targeting of fluorescent molecular imaging agents for completely noninvasive detection of diseased tissue such as breast cancer. These functional groups improve the pharmacokinetic properties of affinity ligands to achieve targeting efficiencies compatible with clinical imaging devices using safe, nonionizing radiation (near-infrared light). Together, this enables development of a "disease screening pill" capable of oral absorption and systemic availability, target binding, background clearance, and imaging at clinically relevant depths for breast cancer screening. This approach should be adaptable to other molecular targets and diseases for use as a new class of screening agents.

Self-organizing team formation for target observation

NASA Astrophysics Data System (ADS)

Bowyer, Richard S.; Bogner, Robert E.

2001-08-01

Target observation is a problem where the application of multiple sensors can improve the probability of detection and observation of the target. Team formation is one method by which seemingly unsophisticated heterogeneous sensors may be organized to achieve a coordinated observation system. The sensors, which we shall refer to as agents, are situated in an area of interest with the goal of observing a moving target. We apply a team approach to this problem, which combines the strengths of individual agents into a cohesive entity - the team. In autonomous systems, the mechanisms that underlie the formation of a team are of interest. Teams may be formed by various mechanisms, which include an externally imposed grouping of agents, or an internally, self-organized (SO) grouping of agents. Internally motivated mechanisms are particularly challenging, but offer the benefit of being unsupervised, an important quality for groups of autonomous cooperating machines. This is the focus of our research. By studying natural systems such as colonies of ants, we obtain insight into these mechanisms of self organization. We propose that the team is an expression of a distributed agent-self, and that a particular realization of the agent-self exists, whilst the environmental conditions are conducive to that existence. We describe an algorithms for agent team formation that is inspired by the self-organizing behavior of ants, and describe simulation results for team formation amongst a lattice of networked sensors.

Colorimetric detection of glucose based on gold nanoparticles coupled with silver nanoparticles

NASA Astrophysics Data System (ADS)

Gao, Yan; Wu, Yiting; Di, Junwei

2017-02-01

We have coupled gold nanoparticles (AuNPs) with silver nanoparticles (AgNPs) to assemble a plasmonic sensing platform for colorimetric detection of glucose. In this system, small AuNPs ( 4 nm) can act as glucose oxidase (GOD) mimic enzyme to catalytically oxidize glucose in the presence of oxygen, producing hydrogen peroxide, which dissolves AgNPs to lead the color changes. Glucose can be detected not only by naked eyes (from yellow to red) but also by spectrophotometer in the concentration range of 5-70 μM, with detection limit of 3 μM. More importantly, we found that L-cysteine added in the system can markedly improve the selectivity for the detection of glucose. The proposed method was used to application for the detection of glucose in human serum with satisfactory results. This system is simple and low cost without using any enzymes and organic chromogenic agents.

Detection of plant quarantine pathogen Ralstonia solanacearum r3b2 with portable POCKIT™ and BLItz® systems

USDA-ARS?s Scientific Manuscript database

Ralstonia solanacearum (Rs) race 3 biovar 2 (r3b2) is designated as a quarantine pathogen in many countries and additionally as a Select Agent in the United States. Rapid, sensitive and accurate detection methods are urgently needed. We report here the development of two portable platforms for r3b...

Magnetic Enzymatic Platform for Organophosphate Pesticide Detection Using Boron-doped Diamond Electrodes.

PubMed

Pino, Flavio; Ivandini, Tribidasari A; Nakata, Kazuya; Fujishima, Akira; Merkoçi, Arben; Einaga, Yasuaki

2015-01-01

A simple and reliable enzymatic system for organophosporus pesticide detection was successfully developed, by exploiting the synergy between the magnetic beads collection capacity and the outstanding electrochemistry property of boron-doped diamond electrodes. The determination of an organophosphate pesticide, chlorpyrifos (CPF), was performed based on the inhibition system of the enzyme acetylcholinesterase bonded to magnetic beads through a biotin-streptavidin complex system. A better sensitivity was found for a system with magnetic beads in the concentration range of 10(-9) to 10(-5) M. The estimated limits of detection based on IC10 (10% acetylcholinesterase (AChE) inhibition) have been detected and optimized to be 5.7 × 10(-10) M CPF. Spiked samples of water of Yokohama (Japan) have been measured to validate the efficiency of the enzymatic system. The results suggested that the use of magnetic beads to immobilize biomolecules or biosensing agents is suitable to maintain the superiority of BDD electrodes.

Multi-agent systems: effective approach for cancer care information management.

PubMed

Mohammadzadeh, Niloofar; Safdari, Reza; Rahimi, Azin

2013-01-01

Physicians, in order to study the causes of cancer, detect cancer earlier, prevent or determine the effectiveness of treatment, and specify the reasons for the treatment ineffectiveness, need to access accurate, comprehensive, and timely cancer data. The cancer care environment has become more complex because of the need for coordination and communication among health care professionals with different skills in a variety of roles and the existence of large amounts of data with various formats. The goals of health care systems in such a complex environment are correct health data management, providing appropriate information needs of users to enhance the integrity and quality of health care, timely access to accurate information and reducing medical errors. These roles in new systems with use of agents efficiently perform well. Because of the potential capability of agent systems to solve complex and dynamic health problems, health care system, in order to gain full advantage of E- health, steps must be taken to make use of this technology. Multi-agent systems have effective roles in health service quality improvement especially in telemedicine, emergency situations and management of chronic diseases such as cancer. In the design and implementation of agent based systems, planning items such as information confidentiality and privacy, architecture, communication standards, ethical and legal aspects, identification opportunities and barriers should be considered. It should be noted that usage of agent systems only with a technical view is associated with many problems such as lack of user acceptance. The aim of this commentary is to survey applications, opportunities and barriers of this new artificial intelligence tool for cancer care information as an approach to improve cancer care management.

Evaluation of real-time data obtained from gravimetric preparation of antineoplastic agents shows medication errors with possible critical therapeutic impact: Results of a large-scale, multicentre, multinational, retrospective study.

PubMed

Terkola, R; Czejka, M; Bérubé, J

2017-08-01

Medication errors are a significant cause of morbidity and mortality especially with antineoplastic drugs, owing to their narrow therapeutic index. Gravimetric workflow software systems have the potential to reduce volumetric errors during intravenous antineoplastic drug preparation which may occur when verification is reliant on visual inspection. Our aim was to detect medication errors with possible critical therapeutic impact as determined by the rate of prevented medication errors in chemotherapy compounding after implementation of gravimetric measurement. A large-scale, retrospective analysis of data was carried out, related to medication errors identified during preparation of antineoplastic drugs in 10 pharmacy services ("centres") in five European countries following the introduction of an intravenous workflow software gravimetric system. Errors were defined as errors in dose volumes outside tolerance levels, identified during weighing stages of preparation of chemotherapy solutions which would not otherwise have been detected by conventional visual inspection. The gravimetric system detected that 7.89% of the 759 060 doses of antineoplastic drugs prepared at participating centres between July 2011 and October 2015 had error levels outside the accepted tolerance range set by individual centres, and prevented these doses from reaching patients. The proportion of antineoplastic preparations with deviations >10% ranged from 0.49% to 5.04% across sites, with a mean of 2.25%. The proportion of preparations with deviations >20% ranged from 0.21% to 1.27% across sites, with a mean of 0.71%. There was considerable variation in error levels for different antineoplastic agents. Introduction of a gravimetric preparation system for antineoplastic agents detected and prevented dosing errors which would not have been recognized with traditional methods and could have resulted in toxicity or suboptimal therapeutic outcomes for patients undergoing anticancer treatment. © 2017 The Authors. Journal of Clinical Pharmacy and Therapeutics Published by John Wiley & Sons Ltd.

Rapid detection of Bacillus anthracis spores using a super-paramagnetic lateral-flow immunological detection system.

PubMed

Wang, Dian-Bing; Tian, Bo; Zhang, Zhi-Ping; Deng, Jiao-Yu; Cui, Zong-Qiang; Yang, Rui-Fu; Wang, Xu-Ying; Wei, Hong-Ping; Zhang, Xian-En

2013-04-15

There is an urgent need for convenient, sensitive, and specific methods to detect the spores of Bacillus anthracis, the causative agent of anthrax, because of the bioterrorism threat posed by this bacterium. In this study, we firstly develop a super-paramagnetic lateral-flow immunological detection system for B. anthracis spores. This system involves the use of a portable magnetic assay reader, super-paramagnetic iron oxide particles, lateral-flow strips and two different monoclonal antibodies directed against B. anthracis spores. This detection system specifically recognises as few as 400 pure B. anthracis spores in 30 min. This system has a linear range of 4×10³-10⁶ CFU ml⁻¹ and reproducible detection limits of 200 spores mg⁻¹ milk powder and 130 spores mg⁻¹ soil for simulated samples. In addition, this approach shows no obvious cross-reaction with other related Bacillus spores, even at high concentrations, and has no significant dependence on the duration of the storage of the immunological strips. Therefore, this super-paramagnetic lateral-flow immunological detection system is a promising tool for the rapid and sensitive detection of Bacillus anthracis spores under field conditions. Copyright © 2012 Elsevier B.V. All rights reserved.

Thioaptamer Diagnostic System (TDS)

NASA Technical Reports Server (NTRS)

Yang, Xianbin

2015-01-01

AM Biotechnologies, LLC, in partnership with Sandia National Laboratories, has developed a diagnostic device that quickly detects sampled biomarkers. The TDS quickly quantifies clinically relevant biomarkers using only microliters of a single sample. The system combines ambient-stable, long shelf-life affinity assays with handheld, microfluidic gel electrophoresis affinity assay quantification technology. The TDS is easy to use, operates in microgravity, and permits simultaneous quantification of 32 biomarkers. In Phase I of the project, the partners demonstrated that a thioaptamer assay used in the microfluidic instrument could quantify a specific biomarker in serum in the low nanomolar range. The team also identified novel affinity agents to bone-specific alkaline phosphatase (BAP) and demonstrated their ability to detect BAP with the microfluidic instrument. In Phase II, AM Biotech expanded the number of ambient affinity agents and demonstrated a TDS prototype. In the long term, the clinical version of the TDS will provide a robust, flight-tested diagnostic capability for space exploration missions.

High-performance computer aided detection system for polyp detection in CT colonography with fluid and fecal tagging

NASA Astrophysics Data System (ADS)

Liu, Jiamin; Wang, Shijun; Kabadi, Suraj; Summers, Ronald M.

2009-02-01

CT colonography (CTC) is a feasible and minimally invasive method for the detection of colorectal polyps and cancer screening. Computer-aided detection (CAD) of polyps has improved consistency and sensitivity of virtual colonoscopy interpretation and reduced interpretation burden. A CAD system typically consists of four stages: (1) image preprocessing including colon segmentation; (2) initial detection generation; (3) feature selection; and (4) detection classification. In our experience, three existing problems limit the performance of our current CAD system. First, highdensity orally administered contrast agents in fecal-tagging CTC have scatter effects on neighboring tissues. The scattering manifests itself as an artificial elevation in the observed CT attenuation values of the neighboring tissues. This pseudo-enhancement phenomenon presents a problem for the application of computer-aided polyp detection, especially when polyps are submerged in the contrast agents. Second, general kernel approach for surface curvature computation in the second stage of our CAD system could yield erroneous results for thin structures such as small (6-9 mm) polyps and for touching structures such as polyps that lie on haustral folds. Those erroneous curvatures will reduce the sensitivity of polyp detection. The third problem is that more than 150 features are selected from each polyp candidate in the third stage of our CAD system. These high dimensional features make it difficult to learn a good decision boundary for detection classification and reduce the accuracy of predictions. Therefore, an improved CAD system for polyp detection in CTC data is proposed by introducing three new techniques. First, a scale-based scatter correction algorithm is applied to reduce pseudo-enhancement effects in the image pre-processing stage. Second, a cubic spline interpolation method is utilized to accurately estimate curvatures for initial detection generation. Third, a new dimensionality reduction classifier, diffusion map and local linear embedding (DMLLE), is developed for classification and false positives (FP) reduction. Performance of the improved CAD system is evaluated and compared with our existing CAD system (without applying those techniques) using CT scans of 1186 patients. These scans are divided into a training set and a test set. The sensitivity of the improved CAD system increased 18% on training data at a rate of 5 FPs per patient and 15% on test data at a rate of 5 FPs per patient. Our results indicated that the improved CAD system achieved significantly better performance on medium-sized colonic adenomas with higher sensitivity and lower FP rate in CTC.

A fluorogenic near-infrared imaging agent for quantifying plasma and local tissue renin activity in vivo and ex vivo

PubMed Central

Zhang, Jun; Preda, Dorin V.; Vasquez, Kristine O.; Morin, Jeff; Delaney, Jeannine; Bao, Bagna; Percival, M. David; Xu, Daigen; McKay, Dan; Klimas, Michael; Bednar, Bohumil; Sur, Cyrille; Gao, David Z.; Madden, Karen; Yared, Wael; Rajopadhye, Milind

2012-01-01

The renin-angiotensin system (RAS) is well studied for its regulation of blood pressure and fluid homeostasis, as well as for increased activity associated with a variety of diseases and conditions, including cardiovascular disease, diabetes, and kidney disease. The enzyme renin cleaves angiotensinogen to form angiotensin I (ANG I), which is further cleaved by angiotensin-converting enzyme to produce ANG II. Although ANG II is the main effector molecule of the RAS, renin is the rate-limiting enzyme, thus playing a pivotal role in regulating RAS activity in hypertension and organ injury processes. Our objective was to develop a near-infrared fluorescent (NIRF) renin-imaging agent for noninvasive in vivo detection of renin activity as a measure of tissue RAS and in vitro plasma renin activity. We synthesized a renin-activatable agent, ReninSense 680 FAST (ReninSense), using a NIRF-quenched substrate derived from angiotensinogen that is cleaved specifically by purified mouse and rat renin enzymes to generate a fluorescent signal. This agent was assessed in vitro, in vivo, and ex vivo to detect and quantify increases in plasma and kidney renin activity in sodium-sensitive inbred C57BL/6 mice maintained on a low dietary sodium and diuretic regimen. Noninvasive in vivo fluorescence molecular tomographic imaging of the ReninSense signal in the kidney detected increased renin activity in the kidneys of hyperreninemic C57BL/6 mice. The agent also effectively detected renin activity in ex vivo kidneys, kidney tissue sections, and plasma samples. This approach could provide a new tool for assessing disorders linked to altered tissue and plasma renin activity and to monitor the efficacy of therapeutic treatments. PMID:22674025

Online Deception Detection Using BDI Agents

ERIC Educational Resources Information Center

Merritts, Richard A.

2013-01-01

This research has two facets within separate research areas. The research area of Belief, Desire and Intention (BDI) agent capability development was extended. Deception detection research has been advanced with the development of automation using BDI agents. BDI agents performed tasks automatically and autonomously. This study used these…

Integration of multi-array sensors and support vector machines for the detection and classification of organophosphate nerve agents

NASA Astrophysics Data System (ADS)

Land, Walker H., Jr.; Sadik, Omowunmi A.; Embrechts, Mark J.; Leibensperger, Dale; Wong, Lut; Wanekaya, Adam; Uematsu, Michiko

2003-08-01

Due to the increased threats of chemical and biological weapons of mass destruction (WMD) by international terrorist organizations, a significant effort is underway to develop tools that can be used to detect and effectively combat biochemical warfare. Furthermore, recent events have highlighted awareness that chemical and biological agents (CBAs) may become the preferred, cheap alternative WMD, because these agents can effectively attack large populations while leaving infrastructures intact. Despite the availability of numerous sensing devices, intelligent hybrid sensors that can detect and degrade CBAs are virtually nonexistent. This paper reports the integration of multi-array sensors with Support Vector Machines (SVMs) for the detection of organophosphates nerve agents using parathion and dichlorvos as model stimulants compounds. SVMs were used for the design and evaluation of new and more accurate data extraction, preprocessing and classification. Experimental results for the paradigms developed using Structural Risk Minimization, show a significant increase in classification accuracy when compared to the existing AromaScan baseline system. Specifically, the results of this research has demonstrated that, for the Parathion versus Dichlorvos pair, when compared to the AromaScan baseline system: (1) a 23% improvement in the overall ROC Az index using the S2000 kernel, with similar improvements with the Gaussian and polynomial (of degree 2) kernels, (2) a significant 173% improvement in specificity with the S2000 kernel. This means that the number of false negative errors were reduced by 173%, while making no false positive errors, when compared to the AromaScan base line performance. (3) The Gaussian and polynomial kernels demonstrated similar specificity at 100% sensitivity. All SVM classifiers provided essentially perfect classification performance for the Dichlorvos versus Trichlorfon pair. For the most difficult classification task, the Parathion versus Paraoxon pair, the following results were achieved (using the three SVM kernels: (1) ROC Az indices from approximately 93% to greater than 99%, (2) partial Az values from ~79% to 93%, (3) specificities from 76% to ~84% at 100 and 98% sensitivity, and (4) PPVs from 73% to ~84% at 100% and 98% sensitivities. These are excellent results, considering only one atom differentiates these nerve agents.

Paired-agent fluorescent imaging to detect micrometastases in breast sentinel lymph node biopsy: experiment design and protocol development

NASA Astrophysics Data System (ADS)

Li, Chengyue; Xu, Xiaochun; Basheer, Yusairah; He, Yusheng; Sattar, Husain A.; Brankov, Jovan G.; Tichauer, Kenneth M.

2018-02-01

Sentinel lymph node status is a critical prognostic factor in breast cancer treatment and is essential to guide future adjuvant treatment. The estimation that 20-60% of micrometastases are missed by conventional pathology has created a demand for the development of more accurate approaches. Here, a paired-agent imaging approach is presented that employs a control imaging agent to allow rapid, quantitative mapping of microscopic populations of tumor cells in lymph nodes to guide pathology sectioning. To test the feasibility of this approach to identify micrometastases, healthy pig lymph nodes were stained with targeted and control imaging agent solution to evaluate the potential for the agents to diffuse into and out of intact nodes. Aby-029, an anti-EGFR affibody was labeled with IRDye 800CW (LICOR) as targeted agent and IRDye 700DX was hydrolyzed as a control agent. Lymph nodes were stained and rinsed by directly injecting the agents into the lymph nodes after immobilization in agarose gel. Subsequently, lymph nodes were frozen-sectioned and imaged under an 80-um resolution fluorescence imaging system (Pearl, LICOR) to confirm equivalence of spatial distribution of both agents in the entire node. The binding potentials were acquired by a pixel-by-pixel calculation and was found to be 0.02 +/- 0.06 along the lymph node in the absence of binding. The results demonstrate this approach's potential to enhance the sensitivity of lymph node pathology by detecting fewer than 1000 cell in a whole human lymph node.

46 CFR 76.05-1 - Fire detecting systems.

Code of Federal Regulations, 2013 CFR

2013-10-01

... required.1 Open decks or enclosed promenades None required None required. Service spaces: Galleys None... dioxide or clean agent system as described in 46 CFR subpart 95.16 or foam.4 Internal combustion or gas... CFR subpart 95.16.5 Electric propulsive motors or generators of open type None required None required...

46 CFR 76.05-1 - Fire detecting systems.

Code of Federal Regulations, 2014 CFR

2014-10-01

... required.1 Open decks or enclosed promenades None required None required. Service spaces: Galleys None... dioxide or clean agent system as described in 46 CFR subpart 95.16 or foam.4 Internal combustion or gas... CFR subpart 95.16.5 Electric propulsive motors or generators of open type None required None required...

46 CFR 76.05-1 - Fire detecting systems.

Code of Federal Regulations, 2012 CFR

2012-10-01

... required.1 Open decks or enclosed promenades None required None required. Service spaces: Galleys None... dioxide or clean agent system as described in 46 CFR subpart 95.16 or foam.4 Internal combustion or gas... CFR subpart 95.16.5 Electric propulsive motors or generators of open type None required None required...

Detection and Learning of Unexpected Behaviors of Systems of Dynamical Systems by Using the Q2 Abstractions

DTIC Science & Technology

2017-11-01

Finite State Machine ............................................... 21 9 Main Ontological Concepts for Representing Structure of a Multi -Agent...19 NetLogo Simulation of persistent surveillance of circular plume by 4 UAVs ........................36 20 Flocking Emergent Behaviors in Multi -UAV...Region) - Undesirable Group Formation ................................................................................... 40 24 Two UAVs Moving in

A review and guidance for pattern selection in spatiotemporal system

NASA Astrophysics Data System (ADS)

Wang, Chunni; Ma, Jun

2018-03-01

Pattern estimation and selection in media can give important clues to understand the collective response to external stimulus by detecting the observable variables. Both reaction-diffusion systems (RDs) and neuronal networks can be treated as multi-agent systems from molecular level, intrinsic cooperation, competition. An external stimulus or attack can cause collapse of spatial order and distribution, while appropriate noise can enhance the consensus in the spatiotemporal systems. Pattern formation and synchronization stability can bridge isolated oscillators and the network by coupling these nodes with appropriate connection types. As a result, the dynamical behaviors can be detected and discussed by developing different spatial patterns and realizing network synchronization. Indeed, the collective response of network and multi-agent system depends on the local kinetics of nodes and cells. It is better to know the standard bifurcation analysis and stability control schemes before dealing with network problems. In this review, dynamics discussion and synchronization control on low-dimensional systems, pattern formation and synchronization stability on network, wave stability in RDs and neuronal network are summarized. Finally, possible guidance is presented when some physical effects such as polarization field and electromagnetic induction are considered.

In vivo plant flow cytometry: A first proof-of-concept

PubMed Central

Nedosekin, Dmitry A.; Khodakovskaya, Mariya V.; Biris, Alexandru S.; Wang, Daoyuan; Xu, Yang; Villagarcia, Hector; Galanzha, Ekaterina I.; Zharov, Vladimir P.

2011-01-01

In vivo flow cytometry has facilitated advances in the ultrasensitive detection of tumor cells, bacteria, nanoparticles, dyes, and other normal and abnormal objects directly in blood and lymph circulatory systems. Here, we propose in vivo plant flow cytometry for the real-time noninvasive study of nanomaterial transport in xylem and phloem plant vascular systems. As a proof of this concept, we demonstrate in vivo real-time photoacoustic monitoring of quantum dot-carbon nanotube conjugate uptake and uptake by roots and spreading through stem to leaves in a tomato plant. In addition, in vivo scanning cytometry using multimodal photoacoustic, photothermal, and fluorescent detection schematics provided multiplex detection and identification of nanoparticles accumulated in plant leaves in the presence of intensive absorption, scattering, and autofluorescent backgrounds. The use of a portable fiber-based photoacoustic flow cytometer for studies of plant vasculature was demonstrated. These integrated cytometry modalities using both endogenous and exogenous contrast agents have a potential to open new avenues of in vivo study of the nutrients, products of photosynthesis and metabolism, nanoparticles, infectious agents, and other objects transported through plant vasculature. PMID:21905208

Design of Protease Activated Optical Contrast Agents That Exploit a Latent Lysosomotropic Effect for Use in Fluorescence-Guided Surgery

PubMed Central

2015-01-01

There is a need for new molecular-guided contrast agents to enhance surgical procedures such as tumor resection that require a high degree of precision. Cysteine cathepsins are highly up-regulated in a wide variety of cancers, both in tumor cells and in the tumor-supporting cells of the surrounding stroma. Therefore, tools that can be used to dynamically monitor their activity in vivo could be used as imaging contrast agents for intraoperative fluorescence image guided surgery (FGS). Although multiple classes of cathepsin-targeted substrate probes have been reported, most suffer from overall fast clearance from sites of protease activation, leading to reduced signal intensity and duration in vivo. Here we describe the design and synthesis of a series of near-infrared fluorogenic probes that exploit a latent cationic lysosomotropic effect (LLE) to promote cellular retention upon protease activation. These probes show tumor-specific retention, fast activation kinetics, and rapid systemic distribution. We demonstrate that they are suitable for detection of diverse cancer types including breast, colon and lung tumors. Most importantly, the agents are compatible with the existing, FDA approved, da Vinci surgical system for fluorescence guided tumor resection. Therefore, our data suggest that the probes reported here can be used with existing clinical instrumentation to detect tumors and potentially other types of inflammatory lesions to guide surgical decision making in real time. PMID:26039341

Rapid detection of bacteria in drinking water and water contamination case studies

NASA Astrophysics Data System (ADS)

Deininger, Rolf A.; Lee, Jiyoung; Clark, Robert M.

2011-12-01

Water systems are inherently vulnerable to physical, chemical and biologic threats that might compromise a systems' ability to reliably deliver safe water. The ability of a water supply to provide water to its customers can be compromised by destroying or disrupting key physical elements of the water system. However, contamination is generally viewed as the most serious potential terrorist threat to water systems. Chemical or biologic agents could spread throughout a distribution system and result in sickness or death among the consumers and for some agents the presence of the contaminant might not be known until emergency rooms report an increase in patients with a particular set of symptoms. Even without serious health impacts, just the knowledge that a water system had been breached could seriously undermine consumer confidence in public water supplies. Therefore, the ability to rapidly detect contamination, especially microbiological contamination, is highly desirable. The authors summarize water contamination case studies and discuss a technique for identifying microbiological contamination based on ATP bioluminescence. This assay allows an estimation of bacterial populations within minutes and can be applied using a local platform. Previous ATP-based methods requires one hour, one liter of water, and has a sensitivity of 100000 cells for detection. The improved method discussed here is 100 times more sensitive, requires one-hundredth of the sample volume, and is over 10 times faster than standard method. This technique has a great deal of potential for application in situations in which a water system has been compromised.

APDS: Autonomous Pathogen Detection System

DOE Office of Scientific and Technical Information (OSTI.GOV)

Langlois, R G; Brown, S; Burris, L

An early warning system to counter bioterrorism, the Autonomous Pathogen Detection System (APDS) continuously monitors the environment for the presence of biological pathogens (e.g., anthrax) and once detected, it sounds an alarm much like a smoke detector warns of a fire. Long before September 11, 2001, this system was being developed to protect domestic venues and events including performing arts centers, mass transit systems, major sporting and entertainment events, and other high profile situations in which the public is at risk of becoming a target of bioterrorist attacks. Customizing off-the-shelf components and developing new components, a multidisciplinary team developed APDS,more » a stand-alone system for rapid, continuous monitoring of multiple airborne biological threat agents in the environment. The completely automated APDS samples the air, prepares fluid samples in-line, and performs two orthogonal tests: immunoassay and nucleic acid detection. When compared to competing technologies, APDS is unprecedented in terms of flexibility and system performance.« less

Recent trends in soft-tissue infection imaging.

PubMed

Petruzzi, Nicholas; Shanthly, Nylla; Thakur, Mathew

2009-03-01

This article discusses the current techniques and future directions of infection imaging with particular attention to respiratory, central nervous system, abdominal, and postoperative infections. The agents currently in use localize to areas of infection and inflammation. An infection-specific imaging agent would greatly improve the utility of scintigraphy in imaging occult infections. The superior spatial resolution of (18)F-fluorodeoxyglucose positron emission tomography ((18)F-FDG-PET) and its lack of reliance on a functional immune system, gives this agent certain advantages over the other radiopharmaceuticals. In respiratory tract infection imaging, an important advancement would be the ability to quantitatively delineate lung inflammation, allowing one to monitor the therapeutic response in a variety of conditions. Current studies suggest PET should be considered the most accurate quantitative method. Scintigraphy has much to offer in localizing abdominal infection as well as inflammation. We may begin to see a gradual increase in the usage of (18)F-FDG-PET in detecting occult abdominal infections. Commonly used modalities for imaging inflammatory bowel disease are scintigraphy with (111)In-oxine/(99m)Tc-HMPAO labeled autologous white blood cells. The literature on central nervous system infection imaging is relatively scarce. Few clinical studies have been performed and numerous new agents have been developed for this use with varying results. Further studies are needed to more clearly delineate the future direction of this field. In evaluating the postoperative spine, (99m)Tc-ciprofloxacin single-photon emission computed tomography (SPECT) was reported to be >80% sensitive in patients more than 6 months after surgery. FDG-PET has also been suggested for this purpose and may play a larger role than originally thought. It appears PET/computed tomography (CT) is gaining support, especially in imaging those with fever of unknown origin or nonfunctional immune systems. Although an infection-specific agent is lacking, the development of one would greatly advance our ability to detect, localize, and quantify infections. Overall, imaging such an agent via SPECT/CT or PET/CT will pave the way for greater clinical reliability in the localization of infection.

Validation of minicams for measuring concentrations of chemical agent in environmental air

DOE Office of Scientific and Technical Information (OSTI.GOV)

Menton, R.G.; Hayes, T.L.; Chou, Y.L.

1993-05-13

Environmental monitoring for chemical agents is necessary to ensure that notification and appropriate action will be taken in the, event that there is a release exceeding control limits of such agents into the workplace outside of engineering controls. Prior to implementing new analytical procedures for environmental monitoring, precision and accuracy (PA) tests are conducted to ensure that an agent monitoring system performs according to specified accuracy, precision, and sensitivity requirements. This testing not only establishes the accuracy and precision of the method, but also determines what factors can affect the method's performance. Performance measures that are particularly important in agentmore » monitoring include the Detection Limit (DL), Decision Limit (DC), Found Action Level (FAL), and the Target Action Level (TAL). PA experiments were performed at Battelle's Medical Research and Evaluation Facility (MREF) to validate the use of the miniature chemical agent monitoring system (MINICAMs) for measuring environmental air concentrations of sulfur mustard (HD). This presentation discusses the experimental and statistical approaches for characterizing the performance of MINICAMS for measuring HD in air.« less

Detection of chemical agent aerosols

NASA Astrophysics Data System (ADS)

Fox, Jay A.; Ahl, Jeffrey L.; D'Amico, Francis M.; Vanderbeek, Richard G.; Moon, Raphael; Swim, Cynthia R.

1999-05-01

One of the major threats presented by a chemical agent attack is that of a munition exploding overhead and 'raining' aerosols which can contaminate surfaces when they impact. Since contact with these surfaces can be fatal, it is imperative to know when such an attack has taken place and the likely threat density and location. We present the results of an experiment designed to show the utility of a CO2 lidar in detecting such an attack. Testing occurred at Dugway Proving Grounds, Utah and involved the simulation of an explosive airburst chemical attack. Explosions occurred at a height of 30 m and liquid droplets from two chemicals, PEG-200 (polyethylene glycol 200) and TEP (triethylphosphate), were expelled and fell to the ground. The munition was the U.S. Army M9 Simulator, Projectile, Airburst, Liquid (SPAL) system that is designed for chemical warfare training exercises. The instrument that was used to detect the presence of the aerosols was the Laser Standoff Chemical Detector (LSCD) which is a light detection and ranging (LIDAR) system that utilizes a rapidly tunable, pulsed CO2 laser. The LIDAR scanned a horizontal path approximately 5 - 8 m above the ground in order to measure the concentration of liquid deposition. The LIDAR data were later correlated with card data to determine how well the system could predict the location and quantity of liquid deposition on the ground.

Development of sandwich-form biosensor to detect Mycobacterium tuberculosis complex in clinical sputum specimens.

PubMed

Shojaei, Taha Roodbar; Mohd Salleh, Mohamad Amran; Tabatabaei, Meisam; Ekrami, Alireza; Motallebi, Roya; Rahmani-Cherati, Tavoos; Hajalilou, Abdollah; Jorfi, Raheleh

2014-01-01

Mycobacterium tuberculosis, the causing agent of tuberculosis, comes second only after HIV on the list of infectious agents slaughtering many worldwide. Due to the limitations behind the conventional detection methods, it is therefore critical to develop new sensitive sensing systems capable of quick detection of the infectious agent. In the present study, the surface modified cadmium-telluride quantum dots and gold nanoparticles conjunct with two specific oligonucleotides against early secretory antigenic target 6 were used to develop a sandwich-form fluorescence resonance energy transfer-based biosensor to detect M. tuberculosis complex and differentiate M. tuberculosis and M. bovis Bacille Calmette-Guerin simultaneously. The sensitivity and specificity of the newly developed biosensor were 94.2% and 86.6%, respectively, while the sensitivity and specificity of polymerase chain reaction and nested polymerase chain reaction were considerably lower, 74.2%, 73.3% and 82.8%, 80%, respectively. The detection limits of the sandwich-form fluorescence resonance energy transfer-based biosensor were far lower (10 fg) than those of the polymerase chain reaction and nested polymerase chain reaction (100 fg). Although the cost of the developed nanobiosensor was slightly higher than those of the polymerase chain reaction-based techniques, its unique advantages in terms of turnaround time, higher sensitivity and specificity, as well as a 10-fold lower detection limit would clearly recommend this test as a more appropriate and cost-effective tool for large scale operations. Copyright © 2014 Elsevier Editora Ltda. All rights reserved.

Development of electrochemical sensors for trace detection of explosives and for the detection of chemical warfare agents

NASA Astrophysics Data System (ADS)

Berger, T.; Ziegler, H.; Krausa, Michael

2000-08-01

A huge number of chemical sensors are based on electrochemical measurement methods. Particularly amperometric sensorsystems are employed for the fast detection of pollutants in industry and environment as well as for analytic systems in the medical diagnosis. The large number of different applications of electrochemical sensors is based on the high sensitivity of electrochemical methods and on the wide of possibilities to enhance the selectivity by variation of electrochemical and chemical parameters. Besides this, electrochemical sensorsystems are frequently simple to operate, transportable and cheap. Up to now the electrochemical method of cyclic voltammetry is used only seldom for sensors. Clearly the efficiency of cyclic voltammetry can be seen at the sensorsystem for the detection of nitro- and aminotoluenes in solids and waters as presented here. The potentiodynamic sensors system can be employed for the fast and easy risk estimation of contaminated areas. Because of the high sensitivity of electrochemical methods the detection of chemical substances with a low vapor pressure is possible also. The vapor pressure of TNT at room temperature is 7 ppb for instances. With a special electrochemical set-up we were able to measure TNT approximately 10 cm above a TNT-sample. In addition we were able to estimate TNT in the gaseous phase approximately 10 cm above a real plastic mine. Therefore it seems to be possible to develop an electrochemical mien detection. Moreover, we present that the electrochemical detection of RDX, HMX and chemical warfare agents is also possible.

Aspects of Tactical Biological Defense

DTIC Science & Technology

1994-06-03

physical proof of Soviet emplcyment of mycotoxins in those countries had been obtained. 30 Biochemical casualties in Laos, Kampuchea and Afghanistan...detection capability. The current system planned for use is the XM-21 Remote Sensing Chemical Agent Alarm (RSCAAL). It uses infrared sensors to detect...Micrometer(s). min. Minute(s). MS. Mans spectroscopy /mass spectrometer. NBC, Nuclear, biological and chemical. pfu. Plaque forming units--the number of

Paired-agent imaging for resection during surgery (PAIRS) of head and neck squamous cell carcinomas (Conference Presentation)

NASA Astrophysics Data System (ADS)

Samkoe, Kimberley S.; Tichauer, Kenneth M.; Chen, Eunice; Gunn, Jason R.; Hoopes, P. Jack; Wells, Wendy A.; Hasan, Tayyaba; Pogue, Brian W.

2016-03-01

Ninety percent of patients with head and neck squamous cell carcinomas (HNSCC) have overexpression of epidermal growth factor receptor (EGFR), which is correlated with poor prognosis. Complete surgical resection of HNSCC tumors has a large impact on patient survival, where detection of tumor at or close to surgical margins increases the risk of death at 5-years by 90%. In addition, large surgical margins can greatly increase the morbidity experienced by the patient due to functional and cosmetic damage of oral and facial structures. Single fluorescence targeting agents are often used for tumor detection in in vivo pre-clinical imaging; however, the arising signal is qualitative at best because it is a complex mixture of vascular perfusion, vascular leakage, inhibited lymphatic clearance, and receptor binding. In vivo ratiometric receptor concentration imaging (RCI) allows quantification of receptor expression (hence identification of cancerous tissue) by utilizing co-administered paired-agents consisting of a targeted agent and non-targeted perfusion agent to reference the plasma delivery and leakage. A panel of HNSCC tumors with varying levels of EGFR expression (SCC-15 >SCC-25 > SCC-09) have been imaged using ABY-029, a clinically relevant anti-EGFR affibody labeled with IRDye 800CW, and affibody control imaging agent labeled with IRDye 680RD. RCI maps of in vivo tissue have been created and are spatially correlated with EGFR and CD31 immunohistochemistry and basic H and E staining. The RCI threshold parameters for distinguishing tumor from normal tissues (skin and muscle) and the accuracy of margin detection in these tumors will be presented. RCI surgical resection will be further developed using a novel multi-channel, gated fluorescence-guided surgery (FGS) imaging system that is capable of performing RCI in normal room light.

Smart Aerospace eCommerce: Using Intelligent Agents in a NASA Mission Services Ordering Application

NASA Technical Reports Server (NTRS)

Moleski, Walt; Luczak, Ed; Morris, Kim; Clayton, Bill; Scherf, Patricia; Obenschain, Arthur F. (Technical Monitor)

2002-01-01

This paper describes how intelligent agent technology was successfully prototyped and then deployed in a smart eCommerce application for NASA. An intelligent software agent called the Intelligent Service Validation Agent (ISVA) was added to an existing web-based ordering application to validate complex orders for spacecraft mission services. This integration of intelligent agent technology with conventional web technology satisfies an immediate NASA need to reduce manual order processing costs. The ISVA agent checks orders for completeness, consistency, and correctness, and notifies users of detected problems. ISVA uses NASA business rules and a knowledge base of NASA services, and is implemented using the Java Expert System Shell (Jess), a fast rule-based inference engine. The paper discusses the design of the agent and knowledge base, and the prototyping and deployment approach. It also discusses future directions and other applications, and discusses lessons-learned that may help other projects make their aerospace eCommerce applications smarter.

Detecting Distributed SQL Injection Attacks in a Eucalyptus Cloud Environment

NASA Technical Reports Server (NTRS)

Kebert, Alan; Barnejee, Bikramjit; Solano, Juan; Solano, Wanda

2013-01-01

The cloud computing environment offers malicious users the ability to spawn multiple instances of cloud nodes that are similar to virtual machines, except that they can have separate external IP addresses. In this paper we demonstrate how this ability can be exploited by an attacker to distribute his/her attack, in particular SQL injection attacks, in such a way that an intrusion detection system (IDS) could fail to identify this attack. To demonstrate this, we set up a small private cloud, established a vulnerable website in one instance, and placed an IDS within the cloud to monitor the network traffic. We found that an attacker could quite easily defeat the IDS by periodically altering its IP address. To detect such an attacker, we propose to use multi-agent plan recognition, where the multiple source IPs are considered as different agents who are mounting a collaborative attack. We show that such a formulation of this problem yields a more sophisticated approach to detecting SQL injection attacks within a cloud computing environment.

Characterization of image heterogeneity using 2D Minkowski functionals increases the sensitivity of detection of a targeted MRI contrast agent.

PubMed

Canuto, Holly C; McLachlan, Charles; Kettunen, Mikko I; Velic, Marko; Krishnan, Anant S; Neves, Andre' A; de Backer, Maaike; Hu, D-E; Hobson, Michael P; Brindle, Kevin M

2009-05-01

A targeted Gd(3+)-based contrast agent has been developed that detects tumor cell death by binding to the phosphatidylserine (PS) exposed on the plasma membrane of dying cells. Although this agent has been used to detect tumor cell death in vivo, the differences in signal intensity between treated and untreated tumors was relatively small. As cell death is often spatially heterogeneous within tumors, we investigated whether an image analysis technique that parameterizes heterogeneity could be used to increase the sensitivity of detection of this targeted contrast agent. Two-dimensional (2D) Minkowski functionals (MFs) provided an automated and reliable method for parameterization of image heterogeneity, which does not require prior assumptions about the number of regions or features in the image, and were shown to increase the sensitivity of detection of the contrast agent as compared to simple signal intensity analysis. (c) 2009 Wiley-Liss, Inc.

Phase II: Automated System for Aneuploidy Detection in Sperm Final Report CRADA No. TC-1554-98

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wyrobek, W. J.; Dunlay, R. T.

This was a collaborative effort between the University of California, Lawrence Livermore National Laboratory (LLNL) and Cellomics, Inc. (formerly BioDx and Biological Detection, Inc.) to develop an automated system for detecting human sperm aneuploidy. Aneuploidy (an abnormal number of chromosomes) is one of the major categories of chromosomally abnormal sperm, which results in chromosomally defective pregnancies and babies. An automated system would be used for testing the effects of toxic agents and for other research and clinical applications. This collaborated effort was funded by a National Institutes of Environmental Health Services, Phase II, Small Business Innovation Research Program (SBIR) grantmore » to Cellornics (Contract No. N44-ES-82004).« less

Remote detection of explosives using field asymmetric ion mobility spectrometer installed on multicopter.

PubMed

Kostyukevich, Yury; Efremov, Denis; Ionov, Vladimir; Kukaev, Eugene; Nikolaev, Eugene

2017-11-01

The detection of explosives and drugs in hard-to-reach places is a considerable challenge. We report the development and initial experimental characterization of the air analysis system that includes Field Asymmetric Ion Mobility Spectrometer, array of the semiconductor gas sensors and is installed on multicopter. The system was developed based on the commercially available DJI Matrix 100 platform. For data collection and communication with operator, the special compact computer (Intel Compute Stick) was installed onboard. The total weight of the system was 3.3 kg. The system allows the 15-minute flight and provides the remote access to the obtained data. The developed system can be effectively used for the detection of impurities in the air, ecology monitoring, detection of chemical warfare agents, and explosives, what is especially important in light of recent terroristic attacks. The capabilities of the system were tested on the several explosives such as trinitrotoluene and nitro powder. Copyright © 2017 John Wiley & Sons, Ltd.

[Usefulness of the molecular techniques for detecting and/or identifing of parasites and fungi in humans and animals or pathogens transmitted by ticks (Part I)].

PubMed

Myjak, P; Majewska, A C; Bajer, A; Siński, E; Wedrychowicz, H; Gołab, E; Budak, A; Stańczak, J

2001-01-01

After a long period of using basic microscopic, immunological and biochemical methods for diagnosis, rapid development of nucleic acids investigation enabled introduction of specific and sensitive methods of detection of pathogenic agents on the molecular level. Among others, polymerase chain reaction (PCR), discovered in mid of 80'ies and then automatized, offered an attractive alternative to conventional testing systems. In this paper we describe reliable diagnostic tests widely used in the world, including Poland, and capable of detecting different disease agents as parasites and fungi in clinical specimens and pathogens of emerging zoonotic diseases in ticks. The possibilities of using molecular methods for determination of Plasmodium falciparum drug resistance is also discussed. Moreover, the report offers information concerning kinds of molecular tests and institutions in which there are executed.

Deep Raman spectroscopy for the non-invasive standoff detection of concealed chemical threat agents.

PubMed

Izake, Emad L; Cletus, Biju; Olds, William; Sundarajoo, Shankaran; Fredericks, Peter M; Jaatinen, Esa

2012-05-30

Deep Raman spectroscopy has been utilized for the standoff detection of concealed chemical threat agents from a distance of 15 m under real life background illumination conditions. By using combined time and space resolved measurements, various explosive precursors hidden in opaque plastic containers were identified non-invasively. Our results confirm that combined time and space resolved Raman spectroscopy leads to higher selectivity towards the sub-layer over the surface layer as well as enhanced rejection of fluorescence from the container surface when compared to standoff spatially offset Raman spectroscopy. Raman spectra that have minimal interference from the packaging material and good signal-to-noise ratio were acquired within 5 s of measurement time. A new combined time and space resolved Raman spectrometer has been designed with nanosecond laser excitation and gated detection, making it of lower cost and complexity than picosecond-based laboratory systems. Copyright © 2012 Elsevier B.V. All rights reserved.

Toxin activity assays, devices, methods and systems therefor

DOEpatents

Koh, Chung-Yan; Schaff, Ulrich Y.; Sommer, Gregory Jon

2016-04-05

Embodiments of the present invention are directed toward devices, system and method for conducting toxin activity assay using sedimentation. The toxin activity assay may include generating complexes which bind to a plurality of beads in a fluid sample. The complexes may include a target toxin and a labeling agent, or may be generated due to presence of active target toxin and/or labeling agent designed to be incorporated into complexes responsive to the presence of target active toxin. The plurality of beads including the complexes may be transported through a density media, wherein the density media has a lower density than a density of the beads and higher than a density of the fluid sample, and wherein the transporting occurs, at least in part, by sedimentation. Signal may be detected from the labeling agents of the complexes.

EVALUATION REPORT SCIENCE APPLICATIONS INTERNATIONAL CORPORATION S-CAD CHEMICAL AGENT DETECTION SYSTEM

EPA Science Inventory

The USEPA's National Homeland Security Research Center (NHSRC)Technology Testing and Evaluation Program (TTEP) is carrying out performance tests on homeland security technologies. Under TTEP, Battelle recently evaluated the performance of the Science Applications International Co...

Ultrasensitive detection of explosives and chemical warfare agents by low-pressure photoionization mass spectrometry.

PubMed

Sun, Wanqi; Liang, Miao; Li, Zhen; Shu, Jinian; Yang, Bo; Xu, Ce; Zou, Yao

2016-08-15

On-spot monitoring of threat agents needs high sensitive instrument. In this study, a low-pressure photoionization mass spectrometer (LPPI-MS) was employed to detect trace amounts of vapor-phase explosives and chemical warfare agent mimetics under ambient conditions. Under 10-s detection time, the limits of detection of 2,4-dinitrotoluene, nitrotoluene, nitrobenzene, and dimethyl methyl phosphonate were 30, 0.5, 4, and 1 parts per trillion by volume, respectively. As compared to those obtained previously with PI mass spectrometric techniques, an improvement of 3-4 orders of magnitude was achieved. This study indicates that LPPI-MS will open new opportunities for the sensitive detection of explosives and chemical warfare agents. Copyright © 2016 Elsevier B.V. All rights reserved.

New Non-Intrusive Inspection Technologies for Nuclear Security and Nonproliferation

NASA Astrophysics Data System (ADS)

Ledoux, Robert J.

2015-10-01

Comprehensive monitoring of the supply chain for nuclear materials has historically been hampered by non-intrusive inspection systems that have such large false alarm rates that they are impractical in the flow of commerce. Passport Systems, Inc. (Passport) has developed an active interrogation system which detects fissionable material, high Z material, and other contraband in land, sea and air cargo. Passport's design utilizes several detection modalities including high resolution imaging, passive radiation detection, effective-Z (EZ-3D™) anomaly detection, Prompt Neutrons from Photofission (PNPF), and Nuclear Resonance Fluorescence (NRF) isotopic identification. These technologies combine to: detect fissionable, high-Z, radioactive and contraband materials, differentiate fissionable materials from high-Z shielding materials, and isotopically identify actinides, Special Nuclear Materials (SNM), and other contraband (e.g. explosives, drugs, nerve agents). Passport's system generates a 3-D image of the scanned object which contains information such as effective-Z and density, as well as a 2-D image and isotopic and fissionable information for regions of interest.

Detection, Isolation and Characterization of an Agent from Febrile Patients in Malaysia Serologically Reactive with Rickettsia sennetsu.

DTIC Science & Technology

1983-12-01

sennetsu by inoculating mice with the blood and bone marrow homogenates of a patient suffering from "Japanese infectious mononucleosis ." Tanaka and...Rickettsia sennetsu in Cell Culture System. Jpn. J. Microbiol. 9:75-86. Misao, T., and Kobayashi, Y. 1954. Studies on Infectious Mononucleosis . I...Isolation of Etiologic Agent from Blood, Bone Marrow and Lymph Node of a Patient with Infectious Mononucleosis by Using Mice. Tokyo Iji Shinshi 71:683-686

Systems and methods for detecting and processing

DOEpatents

Johnson, Michael M [Livermore, CA; Yoshimura, Ann S [Tracy, CA

2006-03-28

Embodiments of the present invention provides systems and method for detecting. Sensing modules are provided in communication with one or more detectors. In some embodiments, detectors are provided that are sensitive to chemical, biological, or radiological agents. Embodiments of sensing modules include processing capabilities to analyze, perform computations on, and/or run models to predict or interpret data received from one or more detectors. Embodiments of sensing modules form various network configurations with one another and/or with one or more data aggregation devices. Some embodiments of sensing modules include power management functionalities.

Passive Standoff Detection of Chemical Warfare Agents on Surfaces

NASA Astrophysics Data System (ADS)

Thériault, Jean-Marc; Puckrin, Eldon; Hancock, Jim; Lecavalier, Pierre; Lepage, Carmela Jackson; Jensen, James O.

2004-11-01

Results are presented on the passive standoff detection and identification of chemical warfare (CW) liquid agents on surfaces by the Fourier-transform IR radiometry. This study was performed during surface contamination trials at Defence Research and Development Canada-Suffield in September 2002. The goal was to verify that passive long-wave IR spectrometric sensors can potentially remotely detect surfaces contaminated with CW agents. The passive sensor, the Compact Atmospheric Sounding Interferometer, was used in the trial to obtain laboratory and field measurements of CW liquid agents, HD and VX. The agents were applied to high-reflectivity surfaces of aluminum, low-reflectivity surfaces of Mylar, and several other materials including an armored personnel carrier. The field measurements were obtained at a standoff distance of 60 m from the target surfaces. Results indicate that liquid contaminant agents deposited on high-reflectivity surfaces can be detected, identified, and possibly quantified with passive sensors. For low-reflectivity surfaces the presence of the contaminants can usually be detected; however, their identification based on simple correlations with the absorption spectrum of the pure contaminant is not possible.

Greyhound meningoencephalitis: PCR-based detection methods highlight an absence of the most likely primary inducing agents.

PubMed

Daly, P; Drudy, D; Chalmers, W S K; Baxendale, W; Fanning, S; Callanan, J J

2006-12-20

Greyhound meningoencephalitis is currently classified as a breed-associated idiopathic central nervous system inflammatory disorder. The non-suppurative inflammatory response can be distinguished from the other breed-associated disorders based on histopathology and lesion topography, however the nature of the response primarily suggests a viral infection. In the present study PCR and RT-PCR technologies were employed on frozen cerebral tissue from confirmed cases of meningoencephalitis to target specific viruses and protozoa likely to be implicated and to exclude the presence of bacterial 16SrRNA. Secondly, degenerate primers were used to detect viruses of the herpesvirus and flavivirus families. In addition cerebral tissues were probed for West Nile Virus. Viral nucleic acid sequences to Borna disease virus, to louping ill, tick borne encephalitis, West Nile and other flaviviruses were not detected. Canine distemper virus was detected in one animal with 97% homology to strain A75/15. Degenerate PCR for herpesviruses detected viral amplification products in one animal with 90% homology to canine herpesvirus DNA polymerase gene. Protozoal amplification products were only detected in a single dog with pathological confirmation of a combination of lesions of greyhound meningoencephalitis and a protozoal encephalomyelitis. Neospora was confirmed with sequence homology to Austrian strain 1. Bacterial 16SrRNA was not detected. The present study supports previous observations that many of the known microbial causes of canine meningoencephalitis are not involved. Findings could reflect that the causal agent was not specifically targeted for detection, or that the agent is at undetectable levels or has been eliminated from brain tissue. The potential roles of genetics and of molecular mimicry also cannot be discounted.

Methods of Advanced Wound Management for Care of Combined Traumatic and Chemical Warfare Injuries

PubMed Central

Graham, John S.; Gerlach, Travis W.; Logan, Thomas P.; Bonar, James P.; Fugo, Richard J.; Lee, Robyn B.; Coatsworth, Matthew A.

2008-01-01

Objective: Chemical warfare agents are potential threats to military personnel and civilians. The potential for associated traumatic injuries is significant. Damage control surgery could expose medical personnel to agents contaminating the wounds. The objectives of this study were to demonstrate efficacy of surgical decontamination and assess exposure risk to attending personnel. Methods: Weanling pigs were randomly assigned to 2 of 4 debridement tools (scalpel, Bovie® knife, Fugo Blade®, and Versajet™ Hydrosurgery System). Penetrating traumatic wounds were created over the shoulder and thigh and then exposed to liquid sulfur mustard (HD) for 60 minutes. Excisional debridement of the injuries was performed while vapors over each site were collected. Gas chromatography was used to measure HD in samples of collected vapors. Unbound HD was quantified in presurgical wound swabs, excised tissues, and peripheral tissue biopsies following solvent extraction. Results: Excisional debridement produced agent-free wound beds (surgical decontamination). A significant amount of HD vapor was detected above the surgical fields with each tool. Apart from the Versajet™ producing significantly lower levels of HD detected over thigh wounds compared with those treated using the scalpel, there were no differences in the amount of agent detected among the tools. All measured levels significantly exceeded established safety limits. Vesicating levels of unbound HD were extracted from excised tissue. There was no measured lateral spreading of HD beyond the surgical margins. Conclusions: There is significant occupational exposure risk to HD during surgical procedures designed to stabilize agent-contaminated wounds. If appropriate protective measures are taken, surgical decontamination is both effective and safe. PMID:18716652

Characterizing emergent properties of immunological systems with multi-cellular rule-based computational modeling.

PubMed

Chavali, Arvind K; Gianchandani, Erwin P; Tung, Kenneth S; Lawrence, Michael B; Peirce, Shayn M; Papin, Jason A

2008-12-01

The immune system is comprised of numerous components that interact with one another to give rise to phenotypic behaviors that are sometimes unexpected. Agent-based modeling (ABM) and cellular automata (CA) belong to a class of discrete mathematical approaches in which autonomous entities detect local information and act over time according to logical rules. The power of this approach lies in the emergence of behavior that arises from interactions between agents, which would otherwise be impossible to know a priori. Recent work exploring the immune system with ABM and CA has revealed novel insights into immunological processes. Here, we summarize these applications to immunology and, particularly, how ABM can help formulate hypotheses that might drive further experimental investigations of disease mechanisms.

An Acoustic Plate Mode Sensor for Biowarfare Toxins, Phase II

DTIC Science & Technology

1997-10-01

Biological agents -- such as bacteria , bacterial toxins and viruses -- must be detected rapidly to allow their neutralization or the quick treatment of...Results were comparable. 16 * r Cyclic voltammetry (CV) studies indicate that the monolayers made with the thiodialkyne, D1, which have been photolyzed...Microprocessor system development is ahead of schedule. Preliminary biosensor data is offered using Y. Pestis. The data indi- cates marginal detection

Chromatographic immunoassays: strategies and recent developments in the analysis of drugs and biological agents

PubMed Central

Matsuda, Ryan; Rodriguez, Elliott; Suresh, Doddavenkatanna; Hage, David S

2015-01-01

A chromatographic immunoassay is a technique in which an antibody or antibody-related agent is used as part of a chromatographic system for the isolation or measurement of a specific target. Various binding agents, detection methods, supports and assay formats have been developed for this group of methods, and applications have been reported that range from drugs, hormones and herbicides to peptides, proteins and bacteria. This review discusses the general principles and applications of chromatographic immunoassays, with an emphasis being given to methods and formats that have been developed for the analysis of drugs and biological agents. The relative advantages or limitations of each format are discussed. Recent developments and research in this field, as well as possible future directions, are also considered. PMID:26571109

Rapid detection of biothreat agents based on cellular machinery.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lane, Todd W.; Gantt, Richard W.

This research addresses rapid and sensitive identification of biological agents in a complex background. We attempted to devise a method by which the specificity of the cellular transcriptional machinery could be used to detect and identify bacterial bio-terror agents in a background of other organisms. Bacterial cells contain RNA polymerases and transcription factors that transcribe genes into mRNA for translation into proteins. RNA polymerases in conjunction with transcription factors recognize regulatory elements (promoters) upstream of the gene. These promoters are, in many cases, recognized by the polymerase and transcription factor combinations of one species only. We have engineered a plasmid,more » for Escherichia coli, containing the virA promoter from the target species Shigella flexneri. This promoter was fused to a reporter gene Green Fluorescent Protein (GFP). In theory the indicator strain (carrying the plasmid) is mixed with the target strain and the two are lysed. The cellular machinery from both cells mixes and the GFP is produced. This report details the results of testing this system.« less

Stand-off spectroscopy for the detection of chemical warfare agents

NASA Astrophysics Data System (ADS)

Clewes, Rhea J.; Howle, Chris R.; Stothard, David J. M.; Dunn, Malcolm H.; Robertson, Gordon; Miller, William; Malcolm, Graeme; Maker, Gareth; Cox, Rick; Williams, Brad; Russell, Matt

2012-10-01

The most desirable configuration for detection of toxic chemicals utilises the maximum distance between detector and hazard. This approach minimises the contamination of equipment or personnel. Where the target chemical is an involatile liquid, indirect detection of the liquid contamination is made difficult by inherently low vapour pressure. In this instance, direct detection of the chemical hazard is the best approach. Recent technology developments have allowed spectroscopic systems to provide multiple options for the stand-off detection of involatile chemical warfare agents (CWAs). Two different stand-off spectroscopic systems, based upon IR absorption and Raman spectroscopic techniques are described here. The Negative Contrast Imager (NCI) is based upon an optical parametric oscillator (OPO) source comprising a Q-switched intracavity MgO:PPLN crystal. This crystal has a fanned grating design and wavelength tuning is achieved by translating the PPLN crystal within the 1064 nm pump beam. This approach enables the production of shortwave and midwave IR radiation (1.5 - 1.8 μm and 2.6 - 3.8 μm, respectively), which is scanned across the scene of interest. Target materials that have an absorption feature commensurate with the wavelength of incoming radiation reduce the intensity of returned signal, resulting in dark pixels in the acquired image. This method enables location and classification of the target material. Stand-off Raman spectroscopy allows target chemicals to be identified at range through comparison of the acquired signature relative to a spectral database. In this work, we used a Raman system based upon a 1047 nm Nd:YLF laser source and a proprietary InGaAsP camera system. Utilisation of a longer excitation wavelength than most conventional stand-off detection systems (e.g. 532 or 785 nm) enables reduction of fluorescence from both the surface and the deposited chemicals, thereby revealing the Raman spectrum. NCI and Raman spectroscopy are able to detect CWAs on surfaces at distances of 2 - 10 metres and have potential to detect over longer ranges. We report the successful identification of at least 60 μl of nitrogen mustard at a distance of a 2 m and 10 m using NCI and Raman spectroscopy.

Dynamic MRI-based computer aided diagnostic systems for early detection of kidney transplant rejection: A survey

NASA Astrophysics Data System (ADS)

Mostapha, Mahmoud; Khalifa, Fahmi; Alansary, Amir; Soliman, Ahmed; Gimel'farb, Georgy; El-Baz, Ayman

2013-10-01

Early detection of renal transplant rejection is important to implement appropriate medical and immune therapy in patients with transplanted kidneys. In literature, a large number of computer-aided diagnostic (CAD) systems using different image modalities, such as ultrasound (US), magnetic resonance imaging (MRI), computed tomography (CT), and radionuclide imaging, have been proposed for early detection of kidney diseases. A typical CAD system for kidney diagnosis consists of a set of processing steps including: motion correction, segmentation of the kidney and/or its internal structures (e.g., cortex, medulla), construction of agent kinetic curves, functional parameter estimation, diagnosis, and assessment of the kidney status. In this paper, we survey the current state-of-the-art CAD systems that have been developed for kidney disease diagnosis using dynamic MRI. In addition, the paper addresses several challenges that researchers face in developing efficient, fast and reliable CAD systems for the early detection of kidney diseases.

Personal glucose meters for detection and quantification of a broad range of analytes

DOEpatents

Lu, Yi; Xiang, Yu

2015-02-03

A general methodology for the development of highly sensitive and selective sensors that can achieve portable, low-cost and quantitative detection of a broad range of targets using only a personal glucose meter (PGM) is disclosed. The method uses recognition molecules that are specific for a target agent, enzymes that can convert an enzyme substrate into glucose, and PGM. Also provided are sensors, which can include a solid support to which is attached a recognition molecule that permits detection of a target agent, wherein the recognition molecule specifically binds to the target agent in the presence of the target agent but not significantly to other agents as well as an enzyme that can catalyze the conversion of a substance into glucose, wherein the enzyme is attached directly or indirectly to the recognition molecule, and wherein in the presence of the target agent the enzyme can convert the substance into glucose. The disclosed sensors can be part of a lateral flow device. Methods of using such sensors for detecting target agents are also provided.

Sensitive and comprehensive detection of chemical warfare agents in air by atmospheric pressure chemical ionization ion trap tandem mass spectrometry with counterflow introduction.

PubMed

Seto, Yasuo; Sekiguchi, Hiroshi; Maruko, Hisashi; Yamashiro, Shigeharu; Sano, Yasuhiro; Takayama, Yasuo; Sekioka, Ryoji; Yamaguchi, Shintaro; Kishi, Shintaro; Satoh, Takafumi; Sekiguchi, Hiroyuki; Iura, Kazumitsu; Nagashima, Hisayuki; Nagoya, Tomoki; Tsuge, Kouichiro; Ohsawa, Isaac; Okumura, Akihiko; Takada, Yasuaki; Ezawa, Naoya; Watanabe, Susumu; Hashimoto, Hiroaki

2014-05-06

A highly sensitive and specific real-time field-deployable detection technology, based on counterflow air introduction atmospheric pressure chemical ionization, has been developed for a wide range of chemical warfare agents (CWAs) comprising gaseous (two blood agents, three choking agents), volatile (six nerve gases and one precursor agent, five blister agents), and nonvolatile (three lachrymators, three vomiting agents) agents in air. The approach can afford effective chemical ionization, in both positive and negative ion modes, for ion trap multiple-stage mass spectrometry (MS(n)). The volatile and nonvolatile CWAs tested provided characteristic ions, which were fragmented into MS(3) product ions in positive and negative ion modes. Portions of the fragment ions were assigned by laboratory hybrid mass spectrometry (MS) composed of linear ion trap and high-resolution mass spectrometers. Gaseous agents were detected by MS or MS(2) in negative ion mode. The limits of detection for a 1 s measurement were typically at or below the microgram per cubic meter level except for chloropicrin (submilligram per cubic meter). Matrix effects by gasoline vapor resulted in minimal false-positive signals for all the CWAs and some signal suppression in the case of mustard gas. The moisture level did influence the measurement of the CWAs.

Measurement of 100 B. anthracis Ames spores within 15 minutes by SERS at the US Army Edgewood Chemical Biological Ctr.

NASA Astrophysics Data System (ADS)

Farquharson, Stuart; Shende, Chetan; Smith, Wayne; Huang, Hermes; Sperry, Jay; Sickler, Todd; Prugh, Amber; Guicheteau, Jason

2014-05-01

Since the distribution of Bacillus anthracis-Ames spores through the US Postal System, there has been a persistent fear that biological warfare agents will be used by terrorists against our military abroad and our civilians at home. While there has been substantial effort since the anthrax attack of 2001 to develop analyzers to detect this and other biological warfare agents, the analyzers remain either too slow, lack sensitivity, produce high false-positive rates, or cannot be fielded. In an effort to overcome these limitations we have been developing a surface-enhanced Raman spectroscopy system. Here we describe the use of silver nanoparticles functionalized with a short peptide to selectively capture Bacillus anthracis spores and produce SER scattering. Specifically, measurements of 100 B. anthracis-Ames spores/mL in ~25 minutes performed at the US Army's Edgewood Chemical Biological Center are presented. The measurements provide a basis for the development of systems that can detect spores collected from the air or water supplies with the potential of saving lives during a biological warfare attack.

Distributed adaptive neural network control for a class of heterogeneous nonlinear multi-agent systems subject to actuation failures

NASA Astrophysics Data System (ADS)

Cui, Bing; Zhao, Chunhui; Ma, Tiedong; Feng, Chi

2017-02-01

In this paper, the cooperative adaptive consensus tracking problem for heterogeneous nonlinear multi-agent systems on directed graph is addressed. Each follower is modelled as a general nonlinear system with the unknown and nonidentical nonlinear dynamics, disturbances and actuator failures. Cooperative fault tolerant neural network tracking controllers with online adaptive learning features are proposed to guarantee that all agents synchronise to the trajectory of one leader with bounded adjustable synchronisation errors. With the help of linear quadratic regulator-based optimal design, a graph-dependent Lyapunov proof provides error bounds that depend on the graph topology, one virtual matrix and some design parameters. Of particular interest is that if the control gain is selected appropriately, the proposed control scheme can be implemented in a unified framework no matter whether there are faults or not. Furthermore, the fault detection and isolation are not needed to implement. Finally, a simulation is given to verify the effectiveness of the proposed method.

Detection and quantification of explosives and CWAs using a handheld widely tunable quantum cascade laser

NASA Astrophysics Data System (ADS)

Deutsch, Erik R.; Haibach, Frederick G.; Mazurenko, Alexander

2012-06-01

The requirements for standoff detection of Explosives and CWA/TICs on surfaces in the battlefield are challenging because of the low detection limits. The variety of targets, backgrounds and interferences increase the challenges. Infrared absorption spectroscopy with traditional infrared detection technologies, incandescent sources that offer broad wavelength range but poor spectral intensity, are particularly challenged in standoff applications because most photons are lost to the target, background and the environment. Using a brighter source for active infrared detection e.g. a widely-tunable quantum cascade laser (QCL) source, provides sufficient spectral intensity to achieve the needed sensitivity and selectivity for explosives, CWAs, and TICs on surfaces. Specific detection of 1-10 μg/cm2 is achieved within seconds. CWAs, and TICs in vapor and aerosol form present a different challenge. Vapors and aerosols are present at low concentrations, so long pathlengths are required to achieve the desired sensitivity. The collimated output beam from the QCL simplifies multi-reflection cells for vapor detection while also enabling large standoff distances. Results obtained by the QCL system indicate that <1 ppm for vapors can be achieved with specificity in a measurement time of seconds, and the QCL system was successfully able to detect agents in the presence of interferents. QCLs provide additional capabilities for the dismounted warfighter. Given the relatively low power consumption, small package, and instant-on capability of the QCL, a handheld device can provide field teams with early detection of toxic agents and energetic materials in standoff, vapor, or aerosol form using a single technology and device which makes it attractive compared other technologies.

Innovative smart micro sensors for Army weaponry applications

NASA Astrophysics Data System (ADS)

Ruffin, Paul B.; Brantley, Christina; Edwards, Eugene

2008-03-01

Micro sensors offer the potential solution to cost, size, and weight issues associated with smart networked sensor systems designed for environmental/missile health monitoring and rocket out-gassing/fuel leak detection, as well as situational awareness on the battlefield. In collaboration with the University of Arkansas (Fayetteville), University of Alabama (Tuscaloosa and Birmingham), Alabama A&M University (Normal), and Streamline Automation (Huntsville, AL), scientists and engineers at the Army Aviation & Missile Research, Development, and Engineering Center (AMRDEC) are investigating several nano-based technologies to solve the problem of sensing extremely small levels of toxic gases associated with both chemical warfare agents (in air and liquids) and potential rocket motor leaks. Innovative techniques are being devised to adapt voltammetry, which is a well established technique for the detection and quantification of substances dissolved in liquids, to low-cost micro sensors for detecting airborne chemical agents and potential missile propellant leakages. In addition, a surface enhanced Raman scattering (SERS) technique, which enhances Raman scattered light by excitation of surface plasmons on nanoporous metal surfaces (nanospheres), is being investigated to develop novel smart sensors for the detection of chemical agents (including rocket motor out-gassing) and potential detection of home-made explosive devices. In this paper, results are delineated that are associated with experimental studies, which are conducted for the aforementioned cases and for several other nano-based technology approaches. The design challenges of each micro sensor technology approach are discussed. Finally, a comparative analysis of the various innovative micro-sensor techniques is provided.

Nanostructured thermites based on iodine pentoxide for bio agent defeat systems.

NASA Astrophysics Data System (ADS)

Hobosyan, Mkhitar; Kazansky, Alexander; Martirosyan, Karen

2011-10-01

The risk for bioterrorist events involving the intentional airborne release of contagious agents has led to development of new approaches for bio agent defeat technologies both indoors and outdoors. Novel approaches to defeat harmful biological agents have generated a strong demand for new active materials. The preferred solutions are to neutralize the biological agents within the immediate target area by using aerosolized biocidal substances released in situ by high energetic reactions. By using nano-thermite reactions, with energy release up to 25 kJ/cc, based on I2O5/Al nanoparticles we intend to generate high quantity of vaporized iodine for spatial deposition onto harmful bacteria for their destruction. In this report, the effect of reaction product on growth and survival of Escherichia coli (E-coli) expressing GFP (Green Fluorescent Protein) was investigated. Moreover, we developed an approach to increase sensitivity of the detection. The study has shown that I2O5/Al nanosystem is extremely effective to disinfect harmful biological agents such (E-coli) bacteria in seconds.

System and method for detecting components of a mixture including a valving scheme for competition assays

DOEpatents

Koh, Chung-Yan; Piccini, Matthew E.; Singh, Anup K.

2017-09-19

Examples are described including measurement systems for conducting competition assays. A first chamber of an assay device may be loaded with a sample containing a target antigen. The target antigen in the sample may be allowed to bind to antibody-coated beads in the first chamber. A control layer separating the first chamber from a second chamber may then be opened to allow a labeling agent loaded in a first portion of the second chamber to bind to any unoccupied sites on the antibodies. A centrifugal force may then be applied to transport the beads through a density media to a detection region for measurement by a detection unit.

System and method for detecting components of a mixture including a valving scheme for competition assays

DOEpatents

Koh, Chung-Yan; Piccini, Matthew E.; Singh, Anup K.

2017-07-11

Examples are described including measurement systems for conducting competition assays. A first chamber of an assay device may be loaded with a sample containing a target antigen. The target antigen in the sample may be allowed to bind to antibody-coated beads in the first chamber. A control layer separating the first chamber from a second chamber may then be opened to allow a labeling agent loaded in a first portion of the second chamber to bind to any unoccupied sites on the antibodies. A centrifugal force may then be applied to transport the beads through a density media to a detection region for measurement by a detection unit.

Protection of Mobile Agents Execution Using a Modified Self-Validating Branch-Based Software Watermarking with External Sentinel

NASA Astrophysics Data System (ADS)

Tomàs-Buliart, Joan; Fernández, Marcel; Soriano, Miguel

Critical infrastructures are usually controlled by software entities. To monitor the well-function of these entities, a solution based in the use of mobile agents is proposed. Some proposals to detect modifications of mobile agents, as digital signature of code, exist but they are oriented to protect software against modification or to verify that an agent have been executed correctly. The aim of our proposal is to guarantee that the software is being executed correctly by a non trusted host. The way proposed to achieve this objective is by the improvement of the Self-Validating Branch-Based Software Watermarking by Myles et al.. The proposed modification is the incorporation of an external element called sentinel which controls branch targets. This technique applied in mobile agents can guarantee the correct operation of an agent or, at least, can detect suspicious behaviours of a malicious host during the execution of the agent instead of detecting when the execution of the agent have finished.

High level expression and immunochemical characterization of botulinum neurotoxin type F light chain.

PubMed

Chauhan, Ritika; Chauhan, Vinita; Rao, Mula Kameshwar; Chaudhary, Dilip; Bhagyawant, Sameer; Dhaked, Ram Kumar

2018-06-01

Botulinum neurotoxins (BoNTs) are the most toxic biological substances known. Their potential use as biological warfare agent results in their classification as category A biowarfare agent by Centers for Disease Control and Prevention (CDC), USA. Presently, there are no approved detection system and pharmacological treatments for BoNT intoxication. Although a toxoid vaccine is available for immuno-prophylaxis, vaccines cannot reverse the effect of pre-translocated toxin. Direct handling of the live BoNTs for developing detection and therapeutics may pose fatal danger. This concern was addressed by purifying the recombinant catalytically active light chain of BoNT/F. BoNT/F-LC gene was amplified from the genomic DNA using specifically designed primers and expressed in Escherichia coli. Expression and purification profile were optimized under different conditions for biologically active light chain production. Specific polyclonal antibodies generated against type F illustrates in vivo neutralization in mice and rabbit. These antibodies play key role in conceiving the development of high throughput SPR based detection system which is a highly precise label free technique for protein interaction analysis. The presented work is first of its kind, signifying the production of highly stable and active rBoNT/F-LC and its immunochemical characterization. The study aids in paving the path towards developing a persistent detection system as well as in presenting comprehended scheme for in vitro small molecule therapeutics analysis. Copyright © 2018 Elsevier Inc. All rights reserved.

15 CFR 700.71 - Audits and investigations.

Code of Federal Regulations, 2010 CFR

2010-01-01

... interviews and a systems evaluation to detect problems or failures in the implementation of this regulation... Commerce to interview the person's employees or agents, to inspect books, records, documents, other... them, and to inspect a person's property when such interviews and inspections are necessary or...

Detecting Chemical Weapons: Threats, Requirements, Solutions, and Future Challenges

NASA Astrophysics Data System (ADS)

Boso, Brian

2011-03-01

Although chemicals have been reportedly used as weapons for thousands of years, it was not until 1915 at Ypres, France that an industrial chemical, chlorine, was used in World War I as an offensive weapon in significant quantity, causing mass casualties. From that point until today the development, detection, production and protection from chemical weapons has be an organized endeavor of many of the world's armed forces and in more recent times, non-governmental terrorist organizations. The number of Chemical Warfare Agents (CWAs) has steadily increased as research into more toxic substances continued for most of the 20 th century. Today there are over 70 substances including harassing agents like tear gas, incapacitating agents, and lethal agents like blister, blood, chocking, and nerve agents. The requirements for detecting chemical weapons vary depending on the context in which they are encountered and the concept of operation of the organization deploying the detection equipment. The US DoD, for example, has as a requirement, that US forces be able to continue their mission, even in the event of a chemical attack. This places stringent requirements on detection equipment. It must be lightweight (<2 lbs), detect a large array of chemical warfare agents and toxic industrial chemicals, detect and warn at concentration levels and time duration to prevent acute health effects, meet military ruggedness specifications and work over a wide range of temperature and humidity, and have a very high probability of detection with a similarly low probability of false positives. The current technology of choice to meet these stringent requirements is Ion Mobility Spectrometry. Many technologies are capable of detecting chemicals at the trace levels required and have been extensively developed for this application, including, but not limited to: mass spectroscopy, IR spectroscopy, RAMAN spectroscopy, MEMs micro-cantilever sensors, surface acoustic wave sensors, differential mobility spectrometry, and amplifying fluorescence polymers. In the future the requirements for detection equipment will continue to become even more stringent. The continuing increase in the sheer number of threats that will need to be detected, the development of binary agents requiring that even the precursor chemicals be detected, the development of new types of agents unlike any of the current chemistries, and the expansion of the list of toxic industrial chemical will require new techniques with higher specificity and more sensitivity.

Processing Diabetes Mellitus Composite Events in MAGPIE.

PubMed

Brugués, Albert; Bromuri, Stefano; Barry, Michael; Del Toro, Óscar Jiménez; Mazurkiewicz, Maciej R; Kardas, Przemyslaw; Pegueroles, Josep; Schumacher, Michael

2016-02-01

The focus of this research is in the definition of programmable expert Personal Health Systems (PHS) to monitor patients affected by chronic diseases using agent oriented programming and mobile computing to represent the interactions happening amongst the components of the system. The paper also discusses issues of knowledge representation within the medical domain when dealing with temporal patterns concerning the physiological values of the patient. In the presented agent based PHS the doctors can personalize for each patient monitoring rules that can be defined in a graphical way. Furthermore, to achieve better scalability, the computations for monitoring the patients are distributed among their devices rather than being performed in a centralized server. The system is evaluated using data of 21 diabetic patients to detect temporal patterns according to a set of monitoring rules defined. The system's scalability is evaluated by comparing it with a centralized approach. The evaluation concerning the detection of temporal patterns highlights the system's ability to monitor chronic patients affected by diabetes. Regarding the scalability, the results show the fact that an approach exploiting the use of mobile computing is more scalable than a centralized approach. Therefore, more likely to satisfy the needs of next generation PHSs. PHSs are becoming an adopted technology to deal with the surge of patients affected by chronic illnesses. This paper discusses architectural choices to make an agent based PHS more scalable by using a distributed mobile computing approach. It also discusses how to model the medical knowledge in the PHS in such a way that it is modifiable at run time. The evaluation highlights the necessity of distributing the reasoning to the mobile part of the system and that modifiable rules are able to deal with the change in lifestyle of the patients affected by chronic illnesses.

Parallel Molecular Distributed Detection With Brownian Motion.

PubMed

Rogers, Uri; Koh, Min-Sung

2016-12-01

This paper explores the in vivo distributed detection of an undesired biological agent's (BAs) biomarkers by a group of biological sized nanomachines in an aqueous medium under drift. The term distributed, indicates that the system information relative to the BAs presence is dispersed across the collection of nanomachines, where each nanomachine possesses limited communication, computation, and movement capabilities. Using Brownian motion with drift, a probabilistic detection and optimal data fusion framework, coined molecular distributed detection, will be introduced that combines theory from both molecular communication and distributed detection. Using the optimal data fusion framework as a guide, simulation indicates that a sub-optimal fusion method exists, allowing for a significant reduction in implementation complexity while retaining BA detection accuracy.

The processing of social stimuli in early infancy: from faces to biological motion perception.

PubMed

Simion, Francesca; Di Giorgio, Elisa; Leo, Irene; Bardi, Lara

2011-01-01

There are several lines of evidence which suggests that, since birth, the human system detects social agents on the basis of at least two properties: the presence of a face and the way they move. This chapter reviews the infant research on the origin of brain specialization for social stimuli and on the role of innate mechanisms and perceptual experience in shaping the development of the social brain. Two lines of convergent evidence on face detection and biological motion detection will be presented to demonstrate the innate predispositions of the human system to detect social stimuli at birth. As for face detection, experiments will be presented to demonstrate that, by virtue of nonspecific attentional biases, a very coarse template of faces become active at birth. As for biological motion detection, studies will be presented to demonstrate that, since birth, the human system is able to detect social stimuli on the basis of their properties such as the presence of a semi-rigid motion named biological motion. Overall, the empirical evidence converges in supporting the notion that the human system begins life broadly tuned to detect social stimuli and that the progressive specialization will narrow the system for social stimuli as a function of experience. Copyright © 2011 Elsevier B.V. All rights reserved.

[Membrane-filtration immunoassay: reagents, methods and the diagnostic and technical means for detection].

PubMed

Khramov, E N; Osin, N S; Pomelova, V G; Vikha, I V; Bychenkova, T A; Smirnova, V G; Grakina, G I; Kas'ianova, T A

1999-01-01

The comprehensive development of dot-EIA made at the State Research Institute of Biological Instrument-Making Industry has provided devices KIMF-02 and KIMF-03), a base of chemical reagents, immunoassays, test systems for detection of a wide range of causative agents of viral and bacterial infections, that of serodiagnosis of their related diseases. The KIMF-02 kit has undergone engineering and medical tests and recommended for the Ministry of Health of the Russian Federation to produce them in stock. The kit includes all required for analysis even in an ill-equipped laboratory, a set of attached agents ensures a valid visual recording of results. The developed procedures and test systems allow the immunoassay to be as sensitive as TIFA; however, they are laborious and much simpler in design. The simple and rapid procedures of dot-EIA are recommended for incorporation into the a package of laboratory methods for verification of the accumulation of virus-specific antigens in various biological substrata, environmental samples, for control of the activity of antigens and antibodies used in serological tests, for detection of specific antigens in the clinical samples, and for serodiagnosis of infections.

Civilian exposure to toxic agents: emergency medical response.

PubMed

Baker, David

2004-01-01

Civilian populations are at risk from exposure to toxic materials as a result of accidental or deliberate exposure. In addition to industrial hazards, toxic agents designed for use in warfare now are a potential hazard in everyday life through terrorist action. Civil emergency medical responders should be able to adapt their plans for dealing with casualties from hazardous materials (HazMat) to deal with the new threat. Chemical and biological warfare (CBW) and HazMat agents can be viewed as a continuous spectrum. Each of these hazards is characterized by qualities of toxicity, latency of action, persistency, and transmissibility. The incident and medical responses to release of any agent is determined by these characteristics. Chemical and biological wardare agents usually are classified as weapons of mass destruction, but strictly, they are agents of mass injury. The relationship between mass injury and major loss of life depends very much on the protection, organization, and emergency care provided. Detection of a civil toxic agent release where signs and symptoms in casualties may be the first indicator of exposure is different from the military situation where intelligence information and tuned detection systems generally will be available. It is important that emergency medical care should be given in the context of a specific action plan. Within an organized and protected perimeter, triage and decontamination (if the agent is persistent) can proceed while emergency medical care is provided at the same time. The provision of advanced life support (TOXALS) in this zone by protected and trained medical responders now is technically feasible using specially designed ventilation equipment. Leaving life support until after decontamination may have fatal consequences. Casualties from terrorist attacks also may suffer physical as well as toxic trauma and the medical response also should be capable of dealing with mixed injuries.

A programmable palm-size gas analyzer for use in micro-autonomous systems

NASA Astrophysics Data System (ADS)

Gordenker, Robert J. M.; Wise, Kensall D.

2012-06-01

Gas analysis systems having small size, low power, and high selectivity are badly needed for defense (detection of explosives and chemical warfare agents), homeland security, health care, and environmental applications. This paper presents a palm-size gas chromatography system having analysis times of 5-50sec, detection limits less than 1ppb, and an average power dissipation less than one watt. It uses no consumables. The three-chip fluidic system consists of a preconcentrator, a 25cm-3m separation column, and a chemi-resistive detector and is supported by a microcomputer and circuitry for programmable temperature control. The entire system, including the mini-pump and battery, occupies less than 200cc and is configured for use on autonomous robotic vehicles.

Double agents and secret agents: the emerging fields of exogenous chemical exchange saturation transfer and T2-exchange magnetic resonance imaging contrast agents for molecular imaging.

PubMed

Daryaei, Iman; Pagel, Mark D

2015-01-01

Two relatively new types of exogenous magnetic resonance imaging contrast agents may provide greater impact for molecular imaging by providing greater specificity for detecting molecular imaging biomarkers. Exogenous chemical exchange saturation transfer (CEST) agents rely on the selective saturation of the magnetization of a proton on an agent, followed by chemical exchange of a proton from the agent to water. The selective detection of a biomarker-responsive CEST signal and an unresponsive CEST signal, followed by the ratiometric comparison of these signals, can improve biomarker specificity. We refer to this improvement as a "double-agent" approach to molecular imaging. Exogenous T 2 -exchange agents also rely on chemical exchange of protons between the agent and water, especially with an intermediate rate that lies between the slow exchange rates of CEST agents and the fast exchange rates of traditional T 1 and T 2 agents. Because of this intermediate exchange rate, these agents have been relatively unknown and have acted as "secret agents" in the contrast agent research field. This review exposes these secret agents and describes the merits of double agents through examples of exogenous agents that detect enzyme activity, nucleic acids and gene expression, metabolites, ions, redox state, temperature, and pH. Future directions are also provided for improving both types of contrast agents for improved molecular imaging and clinical translation. Therefore, this review provides an overview of two new types of exogenous contrast agents that are becoming useful tools within the armamentarium of molecular imaging.

Functionalized gold nanoparticle supported sensory mechanisms applied in detection of chemical and biological threat agents: a review.

PubMed

Upadhyayula, Venkata K K

2012-02-17

There is a great necessity for development of novel sensory concepts supportive of smart sensing capabilities in defense and homeland security applications for detection of chemical and biological threat agents. A smart sensor is a detection device that can exhibit important features such as speed, sensitivity, selectivity, portability, and more importantly, simplicity in identifying a target analyte. Emerging nanomaterial based sensors, particularly those developed by utilizing functionalized gold nanoparticles (GNPs) as a sensing component potentially offer many desirable features needed for threat agent detection. The sensitiveness of physical properties expressed by GNPs, e.g. color, surface plasmon resonance, electrical conductivity and binding affinity are significantly enhanced when they are subjected to functionalization with an appropriate metal, organic or biomolecular functional groups. This sensitive nature of functionalized GNPs can be potentially exploited in the design of threat agent detection devices with smart sensing capabilities. In the presence of a target analyte (i.e., a chemical or biological threat agent) a change proportional to concentration of the analyte is observed, which can be measured either by colorimetric, fluorimetric, electrochemical or spectroscopic means. This article provides a review of how functionally modified gold colloids are applied in the detection of a broad range of threat agents, including radioactive substances, explosive compounds, chemical warfare agents, biotoxins, and biothreat pathogens through any of the four sensory means mentioned previously. Copyright © 2011 Elsevier B.V. All rights reserved.

Sensitivity to synchronicity of biological motion in normal and amblyopic vision

PubMed Central

Luu, Jennifer Y.; Levi, Dennis M.

2017-01-01

Amblyopia is a developmental disorder of spatial vision that results from abnormal early visual experience usually due to the presence of strabismus, anisometropia, or both strabismus and anisometropia. Amblyopia results in a range of visual deficits that cannot be corrected by optics because the deficits reflect neural abnormalities. Biological motion refers to the motion patterns of living organisms, and is normally displayed as points of lights positioned at the major joints of the body. In this experiment, our goal was twofold. We wished to examine whether the human visual system in people with amblyopia retained the higher-level processing capabilities to extract visual information from the synchronized actions of others, therefore retaining the ability to detect biological motion. Specifically, we wanted to determine if the synchronized interaction of two agents performing a dancing routine allowed the amblyopic observer to use the actions of one agent to predict the expected actions of a second agent. We also wished to establish whether synchronicity sensitivity (detection of synchronized versus desynchronized interactions) is impaired in amblyopic observers relative to normal observers. The two aims are differentiated in that the first aim looks at whether synchronized actions result in improved expected action predictions while the second aim quantitatively compares synchronicity sensitivity, or the ratio of desynchronized to synchronized detection sensitivities, to determine if there is a difference between normal and amblyopic observers. Our results show that the ability to detect biological motion requires more samples in both eyes of amblyopes than in normal control observers. The increased sample threshold is not the result of low-level losses but may reflect losses in feature integration due to undersampling in the amblyopic visual system. However, like normal observers, amblyopes are more sensitive to synchronized versus desynchronized interactions, indicating that higher-level processing of biological motion remains intact. We also found no impairment in synchronicity sensitivity in the amblyopic visual system relative to the normal visual system. Since there is no impairment in synchronicity sensitivity in either the nonamblyopic or amblyopic eye of amblyopes, our results suggest that the higher order processing of biological motion is intact. PMID:23474301

Different blocking agents cause variation in the immunologic detection of proteins transferred to nitrocellulose membranes.

PubMed

Spinola, S M; Cannon, J G

1985-07-16

We compared bovine serum albumin, commercial non-fat dry milk, and Tween 20 as blocking agents for immunologic probing of bacterial proteins transferred to nitrocellulose sheets. There were quantitative and qualitative differences in antigens detected that depended on which blocking agents were used. We suggest that several methods for blocking and washing nitrocellulose should be compared when Western blotting is used to detect immunologically reactive proteins.

Tricks, tips, and literature review on the adapted vaporize system to deliver volatile agents during cardiopulmonary bypass

PubMed Central

Nigro Neto, Caetano; De Simone, Francesco; Cassarà, Luigi; Dos Santos Silva, Carlos Gustavo; Maranhão Cardoso, Thiago Augusto Almeida; Carcò, Francesco; Zangrillo, Alberto; Landoni, Giovanni

2016-01-01

Background: Recently, evidence of cardio-protection and reduction in mortality due to the use of volatile agents during cardiac surgery led to an increase in their use during cardiopulmonary bypass (CPB). These findings seem to be enhanced when the volatile agents are used during all the surgical procedure, including the CPB period. Aims: Since the administration of volatile agents through CPB can be beneficial to the patients, we decided to review the use of volatile agents vaporized in the CPB circuit and to summarize some tricks and tips of this technique using our 10-year experience of Brazilian and Italian centers with a large volume of cardiac surgeries. Study Setting: Hospital. Methods: A literature review. Results: During the use of the volatile agents in CPB, it is very important to analyze all gases that come in and go out of the membrane oxygenators. The proper monitoring of inhaled and exhaled fraction of the gas allows not only monitoring of anesthesia level, but also the detection of possible leakage in the circuit. Any volatile agent in the membrane oxygenator is supposed to pollute the operating theater. This is the major reason why proper scavenging systems are always necessary when this technique is used. Conclusion: While waiting for industry upgrades, we recommend that volatile agents should be used during CPB only by skilled perfusionists and physicians with the aim to reduce postoperative morbidity and mortality. PMID:27052063

[Interference for Various Quench Agents of Chemical Disinfectants on Detection of Endotoxin Activities in Water].

PubMed

Zhang, Can; Liu, Wen-jun; Shi, Yun; An, Dai-zhi; Bai, Miao; Xu, Wen

2015-05-01

The quenching agents such as histidine, glycine, ascorbic acid, Tween-80, sodium sulfite and sodium hyposulfite are commonly used for quenching the residual disinfectant in water. In this paper, in order to select the optimal type and concentration range of quenching agents prior to the Limulus assays, the interference effects of each quenching agent at different concentrations on endotoxin detection were investigated by the Limulus assays of kinetic-turbidity. Our results identified that, as for 0-1.0% concentration of histidine, ascorbic acid, Tween-80, sodium sulfite (pH unadjusted and pH neutral), interference on the Limulus assays was existed. Hence, these quenching agents could not be applied as neutralizers prior to Limulus assays. Although, there was no interference on endotoxin detection for the glycine, a yellow color, developed by the quenching products of glycine and glutaric dialdehyde, contributed to false positive results. Hence, glycine should not be used as quenching agents in Limulus assays for samples containing glutaric dialdehyde. Compared with other quenching agents as histidine, glycine, ascorbic acid, Tween-80, sodium sulfite, 0-1.0% concentration of sodium hyposulfite elicited no obvious interference, while 1.0%-5.0% concentration of sodium hyposulfite illustrated exhibition effect for endotoxin detection. All in all, compared with other quenching agents as histidine, glycine, ascorbic acid, Tween-80 and sodium sulfite, sodium hyposulfite is suitable for quenching chemicals prior to endotoxin detection and less than 0.5% of concentration is allowable.

Thin-Membrane Sensor With Biochemical Switch

NASA Technical Reports Server (NTRS)

Case, George D.; Worley, Jennings F.

1992-01-01

Modular sensor electrochemically detects chemical or biological agent, indicating presence of agent via gate-membrane-crossing ion current triggered by chemical reaction between agent and recognition protein conjugated to channel blocker. Used in such laboratory, industrial, or field applications as detection of bacterial toxins in food, military chemical agents in air, and pesticides or other contaminants in environment. Also used in biological screening for hepatitis, acquired immune-deficiency syndrome, and like.

Remote Continuous Wave and Pulsed Laser Raman Detection of Chemical Warfare Agents Simulants and Toxic Industrial Compounds

NASA Astrophysics Data System (ADS)

Ortiz-Rivera, William; Pacheco-Londoño, Leonardo C.; Hernández-Rivera, Samuel P.

2010-09-01

This study describes the design, assembly, testing and comparison of two Remote Raman Spectroscopy (RRS) systems intended for standoff detection of hazardous chemical liquids. Raman spectra of Chemical Warfare Agents Simulants (CWAS) and Toxic Industrial Compounds (TIC) were measured in the laboratory at a 6.6 m source-target distance using continuous wave (CW) laser detection. Standoff distances for pulsed measurements were 35 m for dimethyl methylphosphonate (DMMP) detection and 60, 90 and 140 m for cyclohexane detection. The prototype systems consisted of a Raman spectrometer equipped with a CCD detector (for CW measurements) and an I-CCD camera with time-gated electronics (for pulsed laser measurements), a reflecting telescope, a fiber optic assembly, a single-line CW laser source (514.5, 488.0, 351.1 and 363.8 nm) and a frequency-doubled single frequency Nd:YAG 532 nm laser (5 ns pulses at 10 Hz). The telescope was coupled to the spectrograph using an optical fiber, and filters were used to reject laser radiation and Rayleigh scattering. Two quartz convex lenses were used to collimate the light from the telescope from which the telescope-focusing eyepiece was removed, and direct it to the fiber optic assembly. To test the standoff sensing system, the Raman Telescope was used in the detection of liquid TIC: benzene, chlorobenzene, toluene, carbon tetrachloride, cyclohexane and carbon disulfide. Other compounds studied were CWAS: dimethylmethyl phosphonate, 2-chloroethyl ethyl sulfide and 2-(butylamino)-ethanethiol. Relative Raman scattering cross sections of liquid CWAS were measured using single-line sources at 532.0, 488.0, 363.8 and 351.1 nm. Samples were placed in glass and quartz vials at the standoff distances from the telescope for the Remote Raman measurements. The mass of DMMP present in water solutions was also quantified as part of the system performance tests.

Detecting Bioterrorism: Is Chemistry Enough?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Omberg, Kristin M.

2014-03-13

This slide shows how most bioaerosol detection systems work. There is a lot of concern in the biothreat community, and in the federal government, about a large-scale aerosolized attack. Because of that, we’ve implemented environmental monitoring programs that use aerosol collectors to continuously monitor for the presence of threat agents in the air. Air samples are usually analyzed using PCR, which is one of the most effective analytical techniques we have for identifying DNA. Experiments and modeling have shown these systems are effective, and can warn public health of an impending crisis in time to mount an effective response.

Radioisotope Detection Device and Methods of Radioisotope Collection

DOEpatents

Tranter, Troy J [Idaho Falls, ID; Oertel, Christopher P [Idaho Falls, ID; Giles, John R [Pocatello, ID; Mann, Nicholas R [Rigby, ID; McIlwain, Michael E [Idaho Falls, ID

2011-04-12

A device for collection of radionuclides includes a mixture of a polymer, a fluorescent organic scintillator and a chemical extractant. A radionuclide detector system includes a collection device comprising a mixture of a polymer, a fluorescent agent and a selective ligand. The system includes at least one photomultiplier tube (PMT). A method of detecting radionuclides includes providing a collector device comprising a mixture comprising a polymer, a fluorescent organic scintillator and a chemical extractant. An aqueous environment is exposed to the device and radionuclides are collected from the environment. Radionuclides can be concentrated within the device.

Ultrasonic Analysis of Peptide- and Antibody-Targeted Microbubble Contrast Agents for Molecular Imaging of αvβ3-Expressing Cells

PubMed Central

Dayton, Paul A.; Pearson, David; Clark, Jarrod; Simon, Scott; Schumann, Patricia A.; Zutshi, Reena; Matsunaga, Terry O.; Ferrara, Katherine W.

2008-01-01

The goal of targeted ultrasound contrast agents is to significantly and selectively enhance the detection of a targeted vascular site. In this manuscript, three distinct contrast agents targeted to the αvβ3 integrin are examined. The αvβ3 integrin has been shown to be highly expressed on metastatic tumors and endothelial cells during neovascularization, and its expression has been shown to correlate with tumor grade. Specific adhesion of these contrast agents to αvβ3-expressing cell monolayers is demonstrated in vitro, and compared with that of nontargeted agents. Acoustic studies illustrate a backscatter amplitude increase from monolayers exposed to the targeted contrast agents of up to 13-fold (22 dB) relative to enhancement due to control bubbles. A linear dependence between the echo amplitude and bubble concentration was observed for bound agents. The decorrelation of the echo from adherent targeted agents is observed over successive pulses as a function of acoustic pressure and bubble density. Frequency–domain analysis demonstrates that adherent targeted bubbles exhibit high-amplitude narrowband echo components, in contrast to the primarily wideband response from free microbubbles. Results suggest that adherent targeted contrast agents are differentiable from free-floating microbubbles, that targeted contrast agents provide higher sensitivity in the detection of angiogenesis, and that conventional ultrasound imaging techniques such as signal subtraction or decorrelation detection can be used to detect integrin-expressing vasculature with sufficient signal-to-noise. PMID:15296677

DOSE RESPONSE DEETERMINATION OF NMDA ANTAGONISTS AND GABA AGONIST ON SUSTAINED ATTENTION.

EPA Science Inventory

We have shown that acute inhalation of toluene impairs sustained attention as assessed with a visual signal detection task (SDT). In vitro studies indicate that the NMDA and GABA systems are primary targets of anesthetic agents and organic solvents such as toluene. Pharmacologica...

Microfluidics-Based Lab-on-Chip Systems in DNA-Based Biosensing: An Overview

PubMed Central

Dutse, Sabo Wada; Yusof, Nor Azah

2011-01-01

Microfluidics-based lab-on-chip (LOC) systems are an active research area that is revolutionising high-throughput sequencing for the fast, sensitive and accurate detection of a variety of pathogens. LOCs also serve as portable diagnostic tools. The devices provide optimum control of nanolitre volumes of fluids and integrate various bioassay operations that allow the devices to rapidly sense pathogenic threat agents for environmental monitoring. LOC systems, such as microfluidic biochips, offer advantages compared to conventional identification procedures that are tedious, expensive and time consuming. This paper aims to provide a broad overview of the need for devices that are easy to operate, sensitive, fast, portable and sufficiently reliable to be used as complementary tools for the control of pathogenic agents that damage the environment. PMID:22163925

Department of Defense Chemical and Biological Defense Programs. Annual Report to Congress 2007

DTIC Science & Technology

2007-04-01

Bio aerosol Detection GREEN CB.37 CB agent Water monitor AMBER CB.42 environmental Fate of agents GREEN CB.45 Self -Detoxifying materials AMBER CB.46...nano-Closure Systems • Self -Detoxifying Surfaces/materials 32 C h a P t e r 2 C he m ic al a nd B io lo gi ca l D ef en se r eq ui re m en ts...resistant, selective permeable materials, and aerosol and vapor-resistant breathable materials. The addition of a self -detoxification component is

'Lowering the threshold of effective deterrence'-Testing the effect of private security agents in public spaces on crime: A randomized controlled trial in a mass transit system.

PubMed

Ariel, Barak; Bland, Matthew; Sutherland, Alex

2017-01-01

Supplementing local police forces is a burgeoning multibillion-dollar private security industry. Millions of formal surveillance agents in public settings are tasked to act as preventative guardians, as their high visibility presence is hypothesized to create a deterrent threat to potential offenders. Yet, rigorous evidence is lacking. We randomly assigned all train stations in the South West of England that experienced crime into treatment and controls conditions over a six-month period. Treatment consisted of directed patrol by uniformed, unarmed security agents. Hand-held trackers on every agent yielded precise measurements of all patrol time in the stations. Count-based regression models, estimated marginal means and odds-ratios are used to assess the effect of these patrols on crimes reported to the police by victims, as well as new crimes detected by police officers. Outcomes are measured at both specified target locations to which security guards were instructed to attend, as well as at the entire station complexes. Analyses show that 41% more patrol visits and 29% more minutes spent by security agents at treatment compared to control stations led to a significant 16% reduction in victim-generated crimes at the entirety of the stations' complexes, with a 49% increase in police-generated detections at the target locations. The findings illustrate the efficacy of private policing for crime prevention theory.

Double agents and secret agents: the emerging fields of exogenous chemical exchange saturation transfer and T2-exchange magnetic resonance imaging contrast agents for molecular imaging

PubMed Central

Daryaei, Iman; Pagel, Mark D

2016-01-01

Two relatively new types of exogenous magnetic resonance imaging contrast agents may provide greater impact for molecular imaging by providing greater specificity for detecting molecular imaging biomarkers. Exogenous chemical exchange saturation transfer (CEST) agents rely on the selective saturation of the magnetization of a proton on an agent, followed by chemical exchange of a proton from the agent to water. The selective detection of a biomarker-responsive CEST signal and an unresponsive CEST signal, followed by the ratiometric comparison of these signals, can improve biomarker specificity. We refer to this improvement as a “double-agent” approach to molecular imaging. Exogenous T2-exchange agents also rely on chemical exchange of protons between the agent and water, especially with an intermediate rate that lies between the slow exchange rates of CEST agents and the fast exchange rates of traditional T1 and T2 agents. Because of this intermediate exchange rate, these agents have been relatively unknown and have acted as “secret agents” in the contrast agent research field. This review exposes these secret agents and describes the merits of double agents through examples of exogenous agents that detect enzyme activity, nucleic acids and gene expression, metabolites, ions, redox state, temperature, and pH. Future directions are also provided for improving both types of contrast agents for improved molecular imaging and clinical translation. Therefore, this review provides an overview of two new types of exogenous contrast agents that are becoming useful tools within the armamentarium of molecular imaging. PMID:27747191

Recent Trends in Soft Tissue Infection Imaging

PubMed Central

Petruzzi, Nicholas; Shanthly, Nylla; Thakur, Mathew

2009-01-01

This article discusses the current techniques and future directions of infection imaging with particular attention to respiratory, CNS, abdominal, and postoperative infections. The agents currently in use localize to areas of infection and inflammation. An infection specific imaging agent would greatly improve the utility of scintigraphy in imaging occult infections. The superior spatial resolution of 18F-FDG PET and its lack of reliance on a functional immune system, gives this agent certain advantages over the other radiopharmaceuticals. In respiratory infection imaging, an important advancement would be the ability to quantitatively delineate lung inflammation, allowing one to monitor the therapeutic response in a variety of conditions. Current studies suggest PET should be considered the most accurate quantitative method. Scintigraphy has much to offer in localizing abdominal infection as well as inflammation. We may begin to see a gradual increase in the usage of FDG PET in detecting occult abdominal infections. Commonly used modalities for imaging inflammatory bowel disease are scintigraphy with 111In-oxine/99mTc-HMPAO labeled autologous white blood cells. The literature on CNS infection imaging is relatively scarce. Few clinical studies have been performed and numerous new agents have been developed for this use with varying results. Further studies are needed to more clearly delineate the future direction of this field. In evaluating the post-operative spine, 99mTc-ciprofloxacin SPECT was reported to be >80% sensitive in patients more than 6 months post-surgery. FDG PET has also been suggested for this purpose and may play a larger role than originally thought. It appears PET/CT is gaining support, especially in imaging those with fever of unknown origin or nonfunctional immune systems. While an infection specific agent is lacking, the development of one would greatly advance our ability to detect, localize, and quantify infections. Overall, imaging such an agent via SPECT/CT or PET/CT will pave the way for greater clinical reliability in the localization of infection. PMID:19187804

Inconsistency as a diagnostic tool in a society of intelligent agents.

PubMed

McShane, Marjorie; Beale, Stephen; Nirenburg, Sergei; Jarrell, Bruce; Fantry, George

2012-07-01

To use the detection of clinically relevant inconsistencies to support the reasoning capabilities of intelligent agents acting as physicians and tutors in the realm of clinical medicine. We are developing a cognitive architecture, OntoAgent, that supports the creation and deployment of intelligent agents capable of simulating human-like abilities. The agents, which have a simulated mind and, if applicable, a simulated body, are intended to operate as members of multi-agent teams featuring both artificial and human agents. The agent architecture and its underlying knowledge resources and processors are being developed in a sufficiently generic way to support a variety of applications. We show how several types of inconsistency can be detected and leveraged by intelligent agents in the setting of clinical medicine. The types of inconsistencies discussed include: test results not supporting the doctor's hypothesis; the results of a treatment trial not supporting a clinical diagnosis; and information reported by the patient not being consistent with observations. We show the opportunities afforded by detecting each inconsistency, such as rethinking a hypothesis, reevaluating evidence, and motivating or teaching a patient. Inconsistency is not always the absence of the goal of consistency; rather, it can be a valuable trigger for further exploration in the realm of clinical medicine. The OntoAgent cognitive architecture, along with its extensive suite of knowledge resources an processors, is sufficient to support sophisticated agent functioning such as detecting clinically relevant inconsistencies and using them to benefit patient-centered medical training and practice. Copyright © 2012 Elsevier B.V. All rights reserved.

Quantum coherence of biophotons and living systems.

PubMed

Bajpai, R P

2003-05-01

Coherence is a property of the description of the system in the classical framework in which the subunits of a system act in a cooperative manner. Coherence becomes classical if the agent causing cooperation is discernible otherwise it is quantum coherence. Both stimulated and spontaneous biophoton signals show properties that can be attributed to the cooperative actions of many photon-emitting units. But the agents responsible for the cooperative actions of units have not been discovered so far. The stimulated signal decays with non-exponential character. It is system and situation specific and sensitive to many physiological and environmental factors. Its measurable holistic parameters are strength, shape, relative strengths of spectral components, and excitation curve. The spontaneous signal is non-decaying with the probabilities of detecting various number of photons to be neither normal nor Poisson. The detected probabilities in a signal of Parmelia tinctorum match with probabilities expected in a squeezed state of photons. It is speculated that an in vivo nucleic acid molecule is an assembly of intermittent quantum patches that emit biophoton in quantum transitions. The distributions of quantum patches and their lifetimes determine the holistic features of biophoton signals, so that the coherence of biophotons is merely a manifestation of the coherence of living systems.

Federal Research and Development Funding: FY2010

DTIC Science & Technology

2009-12-24

weapon systems or components (e.g., the Joint Strike Fighter or missile defense systems), for which an operational need has been determined and an...million to the S&T Directorate to fund developmental testing of the BioWatch Generation 3 biological agent detection system. The Administration requested...142 142 143 143 R&D, Acquisition, and Operations 800 826 825 844 856 Border and Maritime 33 40 40 40 44 Chemical and Biological 200 207 222 207

Sensor-enabled chem/bio contamination detection system dedicated to situational awareness of water distribution security status

NASA Astrophysics Data System (ADS)

Ginsberg, Mark D.; Smith, Eddy D.; VanBlaricum, Vicki; Hock, Vincent F.; Kroll, Dan; Russell, Kevin J.

2010-04-01

Both real events and models have proven that drinking water systems are vulnerable to deliberate and/or accidental contamination. Additionally, homeland security initiatives and modeling efforts have determined that it is relatively easy to orchestrate the contamination of potable water supplies. Such contamination can be accomplished with classic and non-traditional chemical agents, toxic industrial chemicals (TICs), and/or toxic industrial materials (TIMs). Subsequent research and testing has developed a proven network for detection and response to these threats. The method uses offthe- shelf, broad-spectrum analytical instruments coupled with advanced interpretive algorithms. The system detects and characterizes any backflow events involving toxic contaminants by employing unique chemical signature (fingerprint) response data. This instrumentation has been certified by the Office of Homeland Security for detecting deliberate and/or accidental contamination of critical water infrastructure. The system involves integration of several mature technologies (sensors, SCADA, dynamic models, and the HACH HST Guardian Blue instrumentation) into a complete, real-time, management system that also can be used to address other water distribution concerns, such as corrosion. This paper summarizes the reasons and results for installing such a distribution-based detection and protection system.

[Recommendations for selecting antimicrobial agents for in vitro susceptibility studies using automatic and semiautomatic systems].

PubMed

Cantón, Rafael; Alós, Juan Ignacio; Baquero, Fernando; Calvo, Jorge; Campos, José; Castillo, Javier; Cercenado, Emilia; Domínguez, M Angeles; Liñares, Josefina; López-Cerezo, Lorena; Marco, Francesc; Mirelis, Beatriz; Morosini, María-Isabel; Navarro, Ferran; Oliver, Antonio; Pérez-Trallero, Emilio; Torres, Carmen; Martínez-Martínez, Luis

2007-01-01

The number of clinical microbiology laboratories that have incorporated automatic susceptibility testing devices has increased in recent years. The majority of these systems determine MIC values using microdilution panels or specific cards, with grouping into clinical categories (susceptible, intermediate or resistant) and incorporate expert systems to infer resistance mechanisms. This document presents the recommendations of a group of experts designated by Grupo de Estudio de los Mecanismos de Acción y Resistencia a los Antimicrobianos (GEMARA, Study group on mechanisms of action and resistance to antimicrobial agents) and Mesa Española de Normalización de la Sensibilidad y Resistencia a los Antimicrobianos (MENSURA, Spanish Group for Normalizing Antimicrobial Susceptibility and Antimicrobial Resistance), with the aim of including antimicrobial agents and selecting concentrations for the susceptibility testing panels of automatic systems. The following have been defined: various antimicrobial categories (A: must be included in the study panel; B: inclusion is recommended; and C: inclusion is secondary, but may facilitate interpretative reading of the antibiogram) and groups (0: not used in therapeutics but may facilitate the detection of resistance mechanisms; 1: must be studied and always reported; 2: must be studied and selectively reported; 3: must be studied and reported at a second level; and 4: should be studied in urinary tract pathogens isolated in urine and other specimens). Recommended antimicrobial concentrations are adapted from the breakpoints established by EUCAST, CLSI and MENSURA. This approach will lead to more accurate susceptibility testing results with better detection of resistance mechanisms, and allowing to reach the clinical goal of the antibiogram.

Rapid diagnosis of Propionibacterium acnes infection in patient with hyperpyrexia after hematopoietic stem cell transplantation by next-generation sequencing: a case report.

PubMed

Ye, Mingzhi; Wei, Wei; Yang, Zhikai; Li, Yingzhen; Cheng, Shaomin; Wang, Kang; Zhou, Tianliangwen; Sun, Jingmeng; Liu, Sha; Ni, Na; Jiang, Hui; Jiang, Hua

2016-01-08

The rapid determination of pathogenic agent is very important to clinician for guiding their clinical medication. However, current diagnostic methods are of limitation in many aspects, such as detecting range, time-consuming, specificity and sensitivity. In this report, we apply our new-developing pathogen detection method to clarify that Propionibacterium acnes is the causative agent of a two-year-old boy with juvenile myelomonocytic leukemia presenting clinical symptoms including serious rash and hyperpyrexia while traditional clinical methods of diagnosis fail to detect the pathogenic agent and multiple antimicrobial drugs are almost ineffective Propionibacterium acnes is confirmed to be the infectious agent by quantitative real-time polymerase chain reaction. After haploidentical hematopoietic stem cell transplantation, a two-year-old boy with juvenile myelomonocytic leukemia presented to a pediatrist in a medical facility with hyperpyrexia and red skin rash which later changed to black skin rash all over his body. Traditional diagnostic assays were unrevealing, and several routine antimicrobial treatments were ineffective, including the vancomycin, meropenem, tobramycin, cefepime and rifampin. In this case, pediatrist resorted to the next-generation sequencing technology for uncovering potential pathogens so as to direct their use of specific drugs against pathogenic bacteria. Therefore, based on the BGISEQ100 (Ion Proton System) which performed sequencing-by-synthesis, with electrochemical detection of synthesis, and each such reaction coupled to its own sensor, which are in turn organized into a massively parallel sensor array on a complementary metal-oxidesemiconductor chip, we detect and identify the potential pathogens. As a result, we detected a significantly higher abundance of skin bacteria Propionibacterium acnes in patient's blood than controls. It had been reported that patients infected by Propionibacterium acnes almost always had history of immunodeficiency, trauma or surgery. Considering this possible cause, antimicrobial treatment was adjusted to target this rare opportunistic pathogen. Fever and black skin rashes were rapidly reduced after administrating specific drugs against Propionibacterium acnes. This case showed our new-developing pathogen detection method was a powerful tool in assisting clinical diagnosis and treatment. And it should be paid more attention to Propionibacterium acnes infection in clinical cases.

Proximal detection of chemical warfare agents using PMIRRAS

NASA Astrophysics Data System (ADS)

Petryk, Michael W. P.; Marenco, Armando J.

2010-04-01

Non-contact chemical warfare agent detection has been demonstrated on military painted surfaces using polarization modulation infrared reflection-absorption spectroscopy (PMIRRAS). Notably, VX has been detected on chemical agent resistance coating (CARC) paint at a distance of approximately 10 cm. PMIRRAS does not rely on the presence of chemical vapors and is not affected by many common battlefield interferants such as aerosolized dust, water and diesel vapors, etc., making it highly suitable for use in operational environments.

Airborne Particulate Threat Assessment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Patrick Treado; Oksana Klueva; Jeffrey Beckstead

Aerosol threat detection requires the ability to discern between threat agents and ambient background particulate matter (PM) encountered in the environment. To date, Raman imaging technology has been demonstrated as an effective strategy for the assessment of threat agents in the presence of specific, complex backgrounds. Expanding our understanding of the composition of ambient particulate matter background will improve the overall performance of Raman Chemical Imaging (RCI) detection strategies for the autonomous detection of airborne chemical and biological hazards. Improving RCI detection performance is strategic due to its potential to become a widely exploited detection approach by several U.S. governmentmore » agencies. To improve the understanding of the ambient PM background with subsequent improvement in Raman threat detection capability, ChemImage undertook the Airborne Particulate Threat Assessment (APTA) Project in 2005-2008 through a collaborative effort with the National Energy Technology Laboratory (NETL), under cooperative agreement number DE-FC26-05NT42594. During Phase 1 of the program, a novel PM classification based on molecular composition was developed based on a comprehensive review of the scientific literature. In addition, testing protocols were developed for ambient PM characterization. A signature database was developed based on a variety of microanalytical techniques, including scanning electron microscopy, FT-IR microspectroscopy, optical microscopy, fluorescence and Raman chemical imaging techniques. An automated particle integrated collector and detector (APICD) prototype was developed for automated collection, deposition and detection of biothreat agents in background PM. During Phase 2 of the program, ChemImage continued to refine the understanding of ambient background composition. Additionally, ChemImage enhanced the APICD to provide improved autonomy, sensitivity and specificity. Deliverables included a Final Report detailing our findings and APICD Gen II subsystems for automated collection, deposition and detection of ambient particulate matter. Key findings from the APTA Program include: Ambient biological PM taxonomy; Demonstration of key subsystems needed for autonomous bioaerosol detection; System design; Efficient electrostatic collection; Automated bioagent recognition; Raman analysis performance validating Td<9 sec; Efficient collection surface regeneration; and Development of a quantitative bioaerosol defection model. The objective of the APTA program was to advance the state of our knowledge of ambient background PM composition. Operation of an automated aerosol detection system was enhanced by a more accurate assessment of background variability, especially for sensitive and specific sensing strategies like Raman detection that are background-limited in performance. Based on this improved knowledge of background, the overall threat detection performance of Raman sensors was improved.« less

Current methods for detecting the presence of botulinum neurotoxins in food and other biological samples

USDA-ARS?s Scientific Manuscript database

Current methods for detecting the presence of botulinum neurotoxins in food and other biological samples Botulinum neurotoxins (BoNTs), the causative agents of botulism, are among the most lethal human bacterial toxins and the causative agent of botulism. BoNTs are also classified as Select Agents ...

An optical system for detecting 3D high-speed oscillation of a single ultrasound microbubble

PubMed Central

Liu, Yuan; Yuan, Baohong

2013-01-01

As contrast agents, microbubbles have been playing significant roles in ultrasound imaging. Investigation of microbubble oscillation is crucial for microbubble characterization and detection. Unfortunately, 3-dimensional (3D) observation of microbubble oscillation is challenging and costly because of the bubble size—a few microns in diameter—and the high-speed dynamics under MHz ultrasound pressure waves. In this study, a cost-efficient optical confocal microscopic system combined with a gated and intensified charge-coupled device (ICCD) camera were developed to detect 3D microbubble oscillation. The capability of imaging microbubble high-speed oscillation with much lower costs than with an ultra-fast framing or streak camera system was demonstrated. In addition, microbubble oscillations along both lateral (x and y) and axial (z) directions were demonstrated. Accordingly, this system is an excellent alternative for 3D investigation of microbubble high-speed oscillation, especially when budgets are limited. PMID:24049677

Microfluidics-based integrated airborne pathogen detection systems

NASA Astrophysics Data System (ADS)

Northrup, M. Allen; Alleman-Sposito, Jennifer; Austin, Todd; Devitt, Amy; Fong, Donna; Lin, Phil; Nakao, Brian; Pourahmadi, Farzad; Vinas, Mary; Yuan, Bob

2006-09-01

Microfluidic Systems is focused on building microfluidic platforms that interface front-end mesofluidics to handle real world sample volumes for optimal sensitivity coupled to microfluidic circuitry to process small liquid volumes for complex reagent metering, mixing, and biochemical analysis, particularly for pathogens. MFSI is the prime contractor on two programs for the US Department of Homeland Security: BAND (Bioagent Autonomous Networked Detector) and IBADS (Instantaneous Bio-Aerosol Detection System). The goal of BAND is to develop an autonomous system for monitoring the air for known biological agents. This consists of air collection, sample lysis, sample purification, detection of DNA, RNA, and toxins, and a networked interface to report the results. For IBADS, MFSI is developing the confirmatory device which must verify the presence of a pathogen with 5 minutes of an air collector/trigger sounding an alarm. Instrument designs and biological assay results from both BAND and IBADS will be presented.

[Assessment of the quality of laboratory diagnosis of intestinal parasitic diseases by the laboratories participating in the Federal System of External Quality Assessment of Clinical Laboratory Testing].

PubMed

Malakhov, V N; Dovgalev, A S; Astanina, S Iu; Serdiuk, A P

2014-01-01

In 2010-2013, the quality of microscopic detection of the causative agents ofparasitic diseases in the feces has been assessed by the specialists of the laboratories of the therapeutic-and-prophylactic institutions (TPIs) and Hygiene and Epidemiology Centers, Russian Inspectorate for the Protection of Consumer Rights and Human Welfare, which are participants of the Federal System of External Quality Assessment of Clinical Laboratory Testing. Thirty-two specimens containing 16 species of human helminths and 4 species of enteric protozoa in different combinations were examined. The findings suggest that the quality of microscopic detection of the causative agents of parasitic diseases is low in the laboratories of health care facilities and that the specialists of the laboratories of TPIs and Hygiene and Epidemiology Centers, Russian Inspectorate for the Protection of Consumer Rights and Human Welfare, do not not possess the knowledge and skills necessary to make a laboratory diagnosis of helminths and enteric protozoa. The average detection rates of helminths and protozoa were at a level of 64 and 36%, respectively. The correct results showed that the proportion of helminths and protozoa were 94.5 and 5.5%, respectively. According to the biological and epidemiological classification of helminths, there were higher detection rates for contact group parasites (Enterobius vermicularis and Hymenolepis nana) and geohelminths (Ascaris, Trichuris trichiura, and others). Biohelminths (Opisthorchis, tapeworms, and others) Were detectable slightly worse.

Quantitation of five organophosphorus nerve agent metabolites in serum using hydrophilic interaction liquid chromatography and tandem mass spectrometry

PubMed Central

Hamelin, Elizabeth I.; Schulze, Nicholas D.; Shaner, Rebecca L.; Coleman, Rebecca M.; Lawrence, Richard J.; Crow, Brian S.; Jakubowski, E. M.; Johnson, Rudolph C.

2015-01-01

Although nerve agent use is prohibited, concerns remain for human exposure to nerve agents during decommissioning, research, and warfare. Exposure can be detected through the analysis of the hydrolysis products in urine as well as blood. An analytical method to detect exposure to five nerve agents, including VX, VR (Russian VX), GB (sarin), GD (soman) and GF (cyclosarin), through the analysis of the hydrolysis products, which are the primary metabolites, in serum has been developed and characterized. This method uses solid phase extraction coupled with high performance liquid chromatography for separation and isotopic dilution tandem mass spectrometry for detection. An uncommon buffer of ammonium fluoride was used to enhance ionization and improve sensitivity when coupled with hydrophilic interaction liquid chromatography resulting in detection limits from 0.3–0.5 ng/mL. The assessment of two quality control samples demonstrated high accuracy (101–105%) and high precision (5–8%) for the detection of these five nerve agent hydrolysis products in serum. PMID:24633507

Technological advancements for the detection of and protection against biological and chemical warfare agents.

PubMed

Eubanks, Lisa M; Dickerson, Tobin J; Janda, Kim D

2007-03-01

There is a growing need for technological advancements to combat agents of chemical and biological warfare, particularly in the context of the deliberate use of a chemical and/or biological warfare agent by a terrorist organization. In this tutorial review, we describe methods that have been developed both for the specific detection of biological and chemical warfare agents in a field setting, as well as potential therapeutic approaches for treating exposure to these toxic species. In particular, nerve agents are described as a typical chemical warfare agent, and the two potent biothreat agents, anthrax and botulinum neurotoxin, are used as illustrative examples of potent weapons for which countermeasures are urgently needed.

Evidence of VX nerve agent use from contaminated white mustard plants

PubMed Central

Gravett, Matthew R.; Hopkins, Farrha B.; Self, Adam J.; Webb, Andrew J.; Timperley, Christopher M.; Baker, Matthew J.

2014-01-01

The Chemical Weapons Convention prohibits the development, production, acquisition, stockpiling, retention, transfer or use of chemical weapons by Member States. Verification of compliance and investigations into allegations of use require accurate detection of chemical warfare agents (CWAs) and their degradation products. Detection of CWAs such as organophosphorus nerve agents in the environment relies mainly upon the analysis of soil. We now present a method for the detection of the nerve agent VX and its hydrolysis products by gas chromatography and liquid chromatography mass spectrometry of ethanol extracts of contaminated white mustard plants (Sinapis alba) which retained the compounds of interest for up to 45 days. VX is hydrolysed by the plants to ethyl methylphosphonic acid and then to methylphosphonic acid. The utility of white mustard as a nerve agent detector and remediator of nerve agent-polluted sites is discussed. The work described will help deter the employment of VX in conflict. PMID:25104906

Immunoassay procedures for fiber optic sensors

NASA Astrophysics Data System (ADS)

Ligler, Frances S.

1988-04-01

There is an increasing need for the development of an ultrasensitive immunoassay for use with fiber optic sensors. These detection systems can be used for such applications as disease diagnosis, detection of chemical and biological warfare agents or drugs of abuse, pollution control, therapeutic monitoring, and explosive detection. This specific program is designed to produce generic chemistries for use with existing fiber optic-based sensors to detect pathogens of particular threat to Army personnel as determined by USAMRIID. The detection system under development involves the attachment of antibodies to an optical fiber at high density. In addition, the immobilization must be achieved in a way which retains the antibody's ability to bind antigen. The functionality of the antibody will be tested through the binding of a labelled antigen. In the future, this assay could incorporate the antibodies developed by the Army for pathogens of particularly military concern.

pH-Sensitive Microparticles with Matrix-Dispersed Active Agent

NASA Technical Reports Server (NTRS)

Calle, Luz M. (Inventor); Jolley, Scott T. (Inventor); Buhrow, Jerry W. (Inventor); Li, Wenyan (Inventor)

2014-01-01

Methods to produce pH-sensitive microparticles that have an active agent dispersed in a polymer matrix have certain advantages over microcapsules with an active agent encapsulated in an interior compartment/core inside of a polymer wall. The current invention relates to pH-sensitive microparticles that have a corrosion-detecting or corrosion-inhibiting active agent or active agents dispersed within a polymer matrix of the microparticles. The pH-sensitive microparticles can be used in various coating compositions on metal objects for corrosion detecting and/or inhibiting.

Isoelectric Bovine Serum Albumin: Robust Blocking Agent for Enhanced Performance in Optical-Fiber Based DNA Sensing.

PubMed

Wang, Ruoyu; Zhou, Xiaohong; Zhu, Xiyu; Yang, Chao; Liu, Lanhua; Shi, Hanchang

2017-02-24

Surface blocking is a well-known process for reducing unwanted nonspecific adsorption in sensor fabrication, especially important in the emerging field where DNA/RNA applied. Bovine serum albumin (BSA) is one of the most popular blocking agents with an isoelectric point at pH 4.6. Although it is widely recognized that the adsorption of a blocking agent is strongly affected by its net charge and the maximum adsorption is often observed under its isoelectric form, BSA has long been perfunctorily used for blocking merely in neutral solution, showing poor blocking performances in the optical-fiber evanescent wave (OFEW) based sensing toward DNA target. To meet this challenge, we first put forward the view that isoelectric BSA (iep-BSA) has the best blocking performance and use an OFEW sensor platform to demonstrate this concept. An optical-fiber was covalently modified with amino-DNA, and further coupled with the optical system to detect fluorophore labeled complementary DNA within the evanescent field. A dramatic improvement in the reusability of this DNA modified sensing surface was achieved with 120 stable detection cycles, which ensured accurate quantitative bioassay. As expected, the iep-BSA blocked OFEW system showed enhanced sensing performance toward target DNA with a detection limit of 125 pM. To the best of our knowledge, this is the highest number of regeneration cycles ever reported for a DNA immobilized optical-fiber surface. This study can also serve as a good reference and provide important implications for developing similar DNA-directed surface biosensors.

Dosimetry using silver salts

DOEpatents

Warner, Benjamin P.

2003-06-24

The present invention provides a method for detecting ionizing radiation. Exposure of silver salt AgX to ionizing radiation results in the partial reduction of the salt to a mixture of silver salt and silver metal. The mixture is further reduced by a reducing agent, which causes the production of acid (HX) and the oxidized form of the reducing agent (R). Detection of HX indicates that the silver salt has been exposed to ionizing radiation. The oxidized form of the reducing agent (R) may also be detected. The invention also includes dosimeters employing the above method for detecting ionizing radiation.

Method for improved selectivity in photo-activation and detection of molecular diagnostic agents

DOEpatents

Wachter, Eric A.; Fisher, Walter G.; Dees, H. Craig

1998-01-01

A method for the imaging of a particular volume of plant or animal tissue, wherein the plant or animal tissue contains at least one photo-active molecular agent. The method includes the steps of treating the particular volume of the plant or animal tissue with light sufficient to promote a simultaneous two-photon excitation of the photo-active molecular agent contained in the particular volume of the plant or animal tissue, photo-activating at least one of the at least one photo-active molecular agent in the particular volume of the plant or animal tissue, thereby producing at least one photo-activated molecular agent, wherein the at least one photo-activated molecular agent emits energy, detecting the energy emitted by the at least one photo-activated molecular agent, and producing a detected energy signal which is characteristic of the particular volume of plant or animal tissue. The present invention is also a method for the imaging of a particular volume of material, wherein the material contains at least one photo-active molecular agent.

Method for improved selectivity in photo-activation and detection of molecular diagnostic agents

DOEpatents

Wachter, E.A.; Fisher, W.G.; Dees, H.C.

1998-11-10

A method for the imaging of a particular volume of plant or animal tissue, wherein the plant or animal tissue contains at least one photo-active molecular agent. The method includes the steps of treating the particular volume of the plant or animal tissue with light sufficient to promote a simultaneous two-photon excitation of the photo-active molecular agent contained in the particular volume of the plant or animal tissue, photo-activating at least one of the at least one photo-active molecular agent in the particular volume of the plant or animal tissue, thereby producing at least one photo-activated molecular agent, wherein the at least one photo-activated molecular agent emits energy, detecting the energy emitted by the at least one photo-activated molecular agent, and producing a detected energy signal which is characteristic of the particular volume of plant or animal tissue. The present invention is also a method for the imaging of a particular volume of material, wherein the material contains at least one photo-active molecular agent. 13 figs.

Methods for improved selectivity in photo-activation and detection of molecular diagnostic agents

DOEpatents

Wachter, Eric A [Oak Ridge, TN; Fisher, Walter G [Knoxville, TN; Dees, H Craig [Knoxville, TN

2008-03-18

A method for the imaging of a particular volume of plant or animal tissue, wherein the plant or animal tissue contains at least one photo-active molecular agent. The method comprises the steps of treating the particular volume of the plant or animal tissue with light sufficient to promote a simultaneous two-photon excitation of the photo-active molecular agent contained in the particular volume of the plant or animal tissue, photo-activating at least one of the at least one photo-active molecular agent in the particular volume of the plant or animal tissue, thereby producing at least one photo-activated molecular agent, wherein the at least one photo-activated molecular agent emits energy, detecting the energy emitted by the at least one photo-activated molecular agent, and producing a detected energy signal which is characteristic of the particular volume of plant or animal tissue. The present invention also provides a method for the imaging of a particular volume of material, wherein the material contains at least one photo-active molecular agent.

PCR Testing of a Ventilated Caging System to Detect Murine Fur Mites

PubMed Central

Jensen, Eric S; Allen, Kenneth P; Henderson, Kenneth S; Szabo, Aniko; Thulin, Joseph D

2013-01-01

Rodents housed in microisolation caging are commonly monitored for infectious agents by the use of soiled bedding sentinels. This strategy relies on the successful transmission of rodent pathogens from the index rodents via soiled bedding to sentinel cages and the subsequent infection or colonization of sentinel rodents. When the prevalence of a pathogen is low or the target agent is not readily transmitted by soiled bedding, alternative testing methodologies should be used. Given the continued prevalence of institutions self-reporting murine fur mites and with the advent of a new sensitive and specific PCR assay for mites, we sought to determine whether the exhaust system of an individual ventilated caging (IVC) system could be used for monitoring the rack's rodent population for mites rather than relying on the responses of sentinels. We deployed single cages of mice (Mus musculus) that were known to be infested with either Radfordia affinis or Myobia musculi on a 70-cage rack, sampled the horizontal exhaust manifolds weekly, and used the new PCR assay to test these samples for mite DNA. We detected the presence of fur mites at a 94.1% probability of detection within 4 wk of placement. Therefore, we recommend swabbing and testing the shelf exhaust manifolds of IVC racks rather than relying on soiled-bedding sentinels as an indicator of the mite status of the rodents on that rack. PMID:23562030

Human Parvovirus 4 as Potential Cause of Encephalitis in Children, India

PubMed Central

Benjamin, Laura A.; Lewthwaite, Penny; Vasanthapuram, Ravi; Zhao, Guoyan; Sharp, Colin; Simmonds, Peter; Wang, David

2011-01-01

To investigate whether uncharacterized infectious agents were associated with neurologic disease, we analyzed cerebrospinal fluid specimens from 12 children with acute central nervous system infection. A high-throughput pyrosequencing screen detected human parvovirus 4 DNA in cerebrospinal fluid of 2 children with encephalitis of unknown etiology. PMID:21801629

78 FR 18814 - Amendment to the Export Administration Regulations: List of Items Classified Under Export Control...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-28

... RIN 0694-AF73. FOR FURTHER INFORMATION CONTACT: Elizabeth Sangine, Director, Chemical and Biological... detection, identification, warning or monitoring of biological agents that is subject to the licensing... approved collections: (1) The Simplified Network Application Processing + System (control number 0694-0088...

Integrated Semiconductor-based Diagnostics System for Multiplexed Genomic Amplification and Electrochemical Detection of Biothreat Agents

DTIC Science & Technology

2009-01-01

microporous disc with adhesive backing. Figure 6. Illustration of the bottom polypropylene layer with the PCR chamber. PCR Chamber UNCLASSIFIED...consistent heating in the PCR chamber. Using insulation and a modified commercial temperature sensor, consistent thermal cycling was achieved with this

Fire protection for a Martian colony

NASA Astrophysics Data System (ADS)

Beattie, Robert M., Jr.

The fire prevention failures that occurred in Apollo 1 and Challenger accidents are reviewed and used to discuss fire protection measures that should be taken in a Martian colony. Fire detection systems, classes of fire, and suppression agents are described. The organization of fire fighting personnel appropriate for Mars is addressed.

Microdose fluorescence imaging of ABY-029 on an operating microscope adapted by custom illumination and imaging modules.

PubMed

Elliott, Jonathan T; Dsouza, Alisha V; Marra, Kayla; Pogue, Brian W; Roberts, David W; Paulsen, Keith D

2016-09-01

Fluorescence guided surgery has the potential to positively impact surgical oncology; current operating microscopes and stand-alone imaging systems are too insensitive or too cumbersome to maximally take advantage of new tumor-specific agents developed through the microdose pathway. To this end, a custom-built illumination and imaging module enabling picomolar-sensitive near-infrared fluorescence imaging on a commercial operating microscope is described. The limits of detection and system specifications are characterized, and in vivo efficacy of the system in detecting ABY-029 is evaluated in a rat orthotopic glioma model following microdose injections, showing the suitability of the device for microdose phase 0 clinical trials.

Microdose fluorescence imaging of ABY-029 on an operating microscope adapted by custom illumination and imaging modules

PubMed Central

Dsouza, Alisha V.; Marra, Kayla; Pogue, Brian W.; Roberts, David W.; Paulsen, Keith D.

2016-01-01

Fluorescence guided surgery has the potential to positively impact surgical oncology; current operating microscopes and stand-alone imaging systems are too insensitive or too cumbersome to maximally take advantage of new tumor-specific agents developed through the microdose pathway. To this end, a custom-built illumination and imaging module enabling picomolar-sensitive near-infrared fluorescence imaging on a commercial operating microscope is described. The limits of detection and system specifications are characterized, and in vivo efficacy of the system in detecting ABY-029 is evaluated in a rat orthotopic glioma model following microdose injections, showing the suitability of the device for microdose phase 0 clinical trials. PMID:27699098

Measuring indigenous photosynthetic organisms to detect chemical warefare agents in water

DOEpatents

Greenbaum, Elias; Sanders, Charlene A.

2005-11-15

A method of testing water to detect the presence of a chemical or biological warfare agent is disclosed. The method is carried out by establishing control data by providing control water containing indigenous organisms but substantially free of a chemical and a biological warfare agent. Then measuring photosynthetic activity of the control water with a fluorometer to obtain control data to compare with test data to detect the presence of the chemical or agent. The test data is gathered by providing test water comprising the same indigenous organisms as contained in the control water. Further, the test water is suspected of containing the chemical or agent to be tested for. Photosynthetic activity is also measured by fluorescence induction in the test water using a fluorometer.

Analysis of DIRAC's behavior using model checking with process algebra

NASA Astrophysics Data System (ADS)

Remenska, Daniela; Templon, Jeff; Willemse, Tim; Bal, Henri; Verstoep, Kees; Fokkink, Wan; Charpentier, Philippe; Graciani Diaz, Ricardo; Lanciotti, Elisa; Roiser, Stefan; Ciba, Krzysztof

2012-12-01

DIRAC is the grid solution developed to support LHCb production activities as well as user data analysis. It consists of distributed services and agents delivering the workload to the grid resources. Services maintain database back-ends to store dynamic state information of entities such as jobs, queues, staging requests, etc. Agents use polling to check and possibly react to changes in the system state. Each agent's logic is relatively simple; the main complexity lies in their cooperation. Agents run concurrently, and collaborate using the databases as shared memory. The databases can be accessed directly by the agents if running locally or through a DIRAC service interface if necessary. This shared-memory model causes entities to occasionally get into inconsistent states. Tracing and fixing such problems becomes formidable due to the inherent parallelism present. We propose more rigorous methods to cope with this. Model checking is one such technique for analysis of an abstract model of a system. Unlike conventional testing, it allows full control over the parallel processes execution, and supports exhaustive state-space exploration. We used the mCRL2 language and toolset to model the behavior of two related DIRAC subsystems: the workload and storage management system. Based on process algebra, mCRL2 allows defining custom data types as well as functions over these. This makes it suitable for modeling the data manipulations made by DIRAC's agents. By visualizing the state space and replaying scenarios with the toolkit's simulator, we have detected race-conditions and deadlocks in these systems, which, in several cases, were confirmed to occur in the reality. Several properties of interest were formulated and verified with the tool. Our future direction is automating the translation from DIRAC to a formal model.

Detection of electrophilic and nucleophilic chemical agents

DOE Office of Scientific and Technical Information (OSTI.GOV)

McElhanon, James R.; Shepodd, Timothy J.

2014-08-12

A "real time" method for detecting chemical agents generally and particularly electrophilic and nucleophilic species by employing tunable, precursor sensor materials that mimic the physiological interaction of these agents to form highly florescent berberine-type alkaloids that can be easily and rapidly detected. These novel precursor sensor materials can be tuned for reaction with both electrophilic (chemical species, toxins) and nucleophilic (proteins and other biological molecules) species. By bonding or otherwise attaching these precursor molecules to a surface or substrate they can be used in numerous applications.

A Software Framework for Remote Patient Monitoring by Using Multi-Agent Systems Support

PubMed Central

2017-01-01

Background Although there have been significant advances in network, hardware, and software technologies, the health care environment has not taken advantage of these developments to solve many of its inherent problems. Research activities in these 3 areas make it possible to apply advanced technologies to address many of these issues such as real-time monitoring of a large number of patients, particularly where a timely response is critical. Objective The objective of this research was to design and develop innovative technological solutions to offer a more proactive and reliable medical care environment. The short-term and primary goal was to construct IoT4Health, a flexible software framework to generate a range of Internet of things (IoT) applications, containing components such as multi-agent systems that are designed to perform Remote Patient Monitoring (RPM) activities autonomously. An investigation into its full potential to conduct such patient monitoring activities in a more proactive way is an expected future step. Methods A framework methodology was selected to evaluate whether the RPM domain had the potential to generate customized applications that could achieve the stated goal of being responsive and flexible within the RPM domain. As a proof of concept of the software framework’s flexibility, 3 applications were developed with different implementations for each framework hot spot to demonstrate potential. Agents4Health was selected to illustrate the instantiation process and IoT4Health’s operation. To develop more concrete indicators of the responsiveness of the simulated care environment, an experiment was conducted while Agents4Health was operating, to measure the number of delays incurred in monitoring the tasks performed by agents. Results IoT4Health’s construction can be highlighted as our contribution to the development of eHealth solutions. As a software framework, IoT4Health offers extensibility points for the generation of applications. Applications can extend the framework in the following ways: identification, collection, storage, recovery, visualization, monitoring, anomalies detection, resource notification, and dynamic reconfiguration. Based on other outcomes involving observation of the resulting applications, it was noted that its design contributed toward more proactive patient monitoring. Through these experimental systems, anomalies were detected in real time, with agents sending notifications instantly to the health providers. Conclusions We conclude that the cost-benefit of the construction of a more generic and complex system instead of a custom-made software system demonstrated the worth of the approach, making it possible to generate applications in this domain in a more timely fashion. PMID:28347973

Oligonucleotide-based theranostic nanoparticles in cancer therapy

PubMed Central

Shahbazi, Reza; Ozpolat, Bulent; Ulubayram, Kezban

2016-01-01

Theranostic approaches, combining the functionality of both therapy and imaging, have shown potential in cancer nanomedicine. Oligonucleotides such as small interfering RNA and microRNA, which are powerful therapeutic agents, have been effectively employed in theranostic systems against various cancers. Nanoparticles are used to deliver oligonucleotides into tumors by passive or active targeting while protecting the oligonucleotides from nucleases in the extracellular environment. The use of quantum dots, iron oxide nanoparticles and gold nanoparticles and tagging with contrast agents, like fluorescent dyes, optical or magnetic agents and various radioisotopes, has facilitated early detection of tumors and evaluation of therapeutic efficacy. In this article, we review the advantages of theranostic applications in cancer therapy and imaging, with special attention to oligonucleotide-based therapeutics. PMID:27102380

Ligand-directed nanobialys as theranostic agent for drug delivery and manganese-based magnetic resonance imaging of vascular targets.

PubMed

Pan, Dipanjan; Caruthers, Shelton D; Hu, Grace; Senpan, Angana; Scott, Mike J; Gaffney, Patrick J; Wickline, Samuel A; Lanza, Gregory M

2008-07-23

Although gadolinium has been the dominant paramagnetic metal for MR paramagnetic contrast agents, the recent association of this lanthanide with nephrogenic systemic fibrosis, an untreatable disease, has spawned renewed interest in alternative metals for MR molecular imaging. We have developed a self-assembled, manganese(III)-labeled nanobialys (1), a toroidal-shaped MR theranostic nanoparticle. In this report, Mn(III) nanobialys are characterized as MR molecular imaging agents for targeted detection of fibrin, a major biochemical feature of thrombus. A complementary ability of nanobialys to incorporate chemotherapeutic compounds with greater than 98% efficiency and to retain more than 80% of these drugs after infinite sink dissolution, point to the theranostic potential of this platform technology.

Metal cation detection in positive ion mode electrospray ionization mass spectrometry using a tetracationic salt as a gas-phase ion-pairing agent: evaluation of the effect of chelating agents on detection sensitivity.

PubMed

Xu, Chengdong; Dodbiba, Edra; Padivitage, Nilusha L T; Breitbach, Zachary S; Armstrong, Daniel W

2012-12-30

The detection of metal cations continues to be essential in many scientific and industrial areas of interest. The most common electrospray ionization mass spectrometry (ESI-MS) approach involves chelating the metal ions and detecting the organometallic complex in the negative ion mode. However, it is well known that negative ion mode ESI-MS is generally less sensitive than the positive ion mode. To achieve greater sensitivity, it is necessary to examine the feasibility of detecting the chelated metal cations in positive ion mode ESI-MS. Since highly solvated native metal cations have relatively low ionization efficiency in ESI-MS, and can be difficult to detect in the positive ion mode, a tetracationic ion-pairing agent was added to form a complex with the negatively charged metal chelate. The use of the ion-pairing agent leads to the generation of an overall positively charged complex, which can be detected at higher m/z values in the positive ion mode by electrospray ionization linear quadrupole ion trap mass spectrometry. Thirteen chelating agents with diverse structures were evaluated in this study. The nature of the chelating agent played as important a role as was previously determined for cationic pairing agents. The detection limits of six metal cations reached sub-picogram levels and significant improvements were observed when compared to negative ion mode detection where the metal-chelates were monitored without adding the ion-pairing reagent (IPR). Also, selective reaction monitoring (SRM) analyses were performed on the ternary complexes, which improved detection limits by one to three orders of magnitude. With this method it was possible to analyze the metal cations in the positive ion mode ESI-MS with the advantage of speed, sensitivity and selectivity. The optimum solution pH for this type of analysis is 5-7. Tandem mass spectrometry (MS/MS) further increases the sensitivity. Speciation is straightforward making this a broadly useful approach for the analysis of metal ions. Copyright © 2012 John Wiley & Sons, Ltd.

Point-Counterpoint: A Nucleic Acid Amplification Test for Streptococcus pyogenes Should Replace Antigen Detection and Culture for Detection of Bacterial Pharyngitis.

PubMed

Pritt, Bobbi S; Patel, Robin; Kirn, Thomas J; Thomson, Richard B

2016-10-01

Nucleic acid amplification tests (NAATs) have frequently been the standard diagnostic approach when specific infectious agents are sought in a clinic specimen. They can be applied for specific agents such as S. pyogenes, or commercial multiplex NAATs for detection of a variety of pathogens in gastrointestinal, bloodstream, and respiratory infections may be used. NAATs are both rapid and sensitive. For many years, S. pyogenes testing algorithms used a rapid and specific group A streptococcal antigen test to screen throat specimens, followed, in some clinical settings, by a throat culture for S. pyogenes to increase the sensitivity of its detection. Now S. pyogenes NAATs are being used with increasing frequency. Given their accuracy, rapidity, and ease of use, should they replace antigen detection and culture for the detection of bacterial pharyngitis? Bobbi Pritt and Robin Patel of the Mayo Clinic, where S. pyogenes NAATs have been used for well over a decade with great success, will explain the advantages of this approach, while Richard (Tom) Thomson and Tom Kirn of the NorthShore University HealthSystem will discuss their concerns about this approach to diagnosing bacterial pharyngitis. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Detection and identification of alkylating agents by using a bioinspired "chemical nose".

PubMed

Hertzog-Ronen, Carmit; Borzin, Elena; Gerchikov, Yulia; Tessler, Nir; Eichen, Yoav

2009-10-12

Alkylating agents are simple and reactive molecules that are commonly used in many and diverse fields such as organic synthesis, medicine, and agriculture. Some highly reactive alkylating species are also being used as blister chemical-warfare agents. The detection and identification of alkylating agents is not a trivial issue because of their high reactivity and simple structure. Herein, we report on a new multispot luminescence-based approach to the detection and identification of alkylating agents. In order to demonstrate the potential of the approach, seven pi-conjugated oligomers and polymers bearing nucleophilic pyridine groups, 1-7, were adsorbed onto a solid support and exposed to vapors of alkylators 8-15. The alkylation-induced color-shift patterns of the seven-spot array allow clear discrimination of the different alkylators. The spots are sensitive to minute concentrations of alkylators and, because the detection is based on the formation of new covalent bonds, these spots saturate at about 50 ppb.

Biosensor Based on Self-Assembling Acetylcholinesterase on Carbon Nanotubes for Flow injection/Amperometric Detection of Organophosphate Pesticides and Nerve Agents

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Guodong; Lin, Yuehe

A highly sensitive flow-injection amperometric biosensor for organophosphate pesticides and nerve agents based on self-assembly of acetylcholinesterase (AChE) on carbon nanotube (CNT)-modified glassy carbon (GC) electrode is described. AChE is immobilized on the negatively-charged CNT surface by alternatively assembling a cationic polydiallyldimethylammonium chloride (PDDA) layer and an AChE layer. Transmission electron microscopy images confirm the formation of layer-by-layer nanostructures on carboxyl functionalized CNTs. The unique sandwich-like structure (PDDA/AChE/PDDA) on the CNT surface formed by self-assembly provides a favorable microenvironment to keep the bioactivity of AChE and to prevent enzyme molecule leakage. The electrocatalytic activity of CNT leads to a greatlymore » improved electrochemical detection of the enzymatically generated thiocholine product, including a low oxidation overvoltage (+150 mV), higher sensitivity, and stability. The developed PDDA/AChE/PDDA/CNT/GC biosensor integrated into a flow injection system was used to monitor organophosphate pesticides and nerve agents, such as paraoxon. The sensor performance, including inhibition time and regeneration conditions, was optimized with respect to operating conditions. Under the optimal conditions, the biosensor was used to measure as low as 0.4 pM paraoxon with a 6-min inhibition time. The biosensor had excellent operational lifetime stability with no decrease in the activity of enzymes for more than 20 repeated measurements over a 1-week period. The developed biosensor system is an ideal tool for online monitoring of organophosphate pesticides and nerve agents.« less

Metabolic Imaging of Patients with Prostate Cancer Using Hyperpolarized [1-13C]Pyruvate

PubMed Central

Nelson, Sarah J.; Kurhanewicz, John; Vigneron, Daniel B.; Larson, Peder E. Z.; Harzstark, Andrea L.; Ferrone, Marcus; van Criekinge, Mark; Chang, Jose W.; Bok, Robert; Park, Ilwoo; Reed, Galen; Carvajal, Lucas; Small, Eric J.; Munster, Pamela; Weinberg, Vivian K.; Ardenkjaer-Larsen, Jan Henrik; Chen, Albert P.; Hurd, Ralph E.; Odegardstuen, Liv-Ingrid; Robb, Fraser J.; Tropp, James; Murray, Jonathan A.

2014-01-01

This first-in-man imaging study evaluated the safety and feasibility of hyperpolarized [1-13C]pyruvate as an agent for noninvasively characterizing alterations in tumor metabolism for patients with prostate cancer. Imaging living systems with hyperpolarized agents can result in more than 10,000-fold enhancement in signal relative to conventional magnetic resonance (MR) imaging. When combined with the rapid acquisition of in vivo 13C MR data, it is possible to evaluate the distribution of agents such as [1-13C]pyruvate and its metabolic products lactate, alanine, and bicarbonate in a matter of seconds. Preclinical studies in cancer models have detected elevated levels of hyperpolarized [1-13C]lactate in tumor, with the ratio of [1-13C]lactate/[1-13C]pyruvate being increased in high-grade tumors and decreased after successful treatment. Translation of this technology into humans was achieved by modifying the instrument that generates the hyperpolarized agent, constructing specialized radio frequency coils to detect 13C nuclei, and developing new pulse sequences to efficiently capture the signal. The study population comprised patients with biopsy-proven prostate cancer, with 31 subjects being injected with hyperpolarized [1-13C]pyruvate. The median time to deliver the agent was 66 s, and uptake was observed about 20 s after injection. No dose-limiting toxicities were observed, and the highest dose (0.43 ml/kg of 230 mM agent) gave the best signal-to-noise ratio for hyperpolarized [1-13C]pyruvate. The results were extremely promising in not only confirming the safety of the agent but also showing elevated [1-13C]lactate/[1-13C]pyruvate in regions of biopsy-proven cancer. These findings will be valuable for noninvasive cancer diagnosis and treatment monitoring in future clinical trials. PMID:23946197

Reactive chromophores for sensitive and selective detection of chemical warfare agents and toxic industrial chemicals

NASA Astrophysics Data System (ADS)

Frye-Mason, Greg; Leuschen, Martin; Wald, Lara; Paul, Kateri; Hancock, Lawrence F.

2005-05-01

A reactive chromophore developed at MIT exhibits sensitive and selective detection of surrogates for G-class nerve agents. This reporter acts by reacting with the agent to form an intermediate that goes through an internal cyclization reaction. The reaction locks the molecule into a form that provides a strong fluorescent signal. Using a fluorescent sensor platform, Nomadics has demonstrated rapid and sensitive detection of reactive simulants such as diethyl chloro-phosphate (simulant for sarin, soman, and related agents) and diethyl cyanophosphate (simulant for tabun). Since the unreacted chromophore does not fluoresce at the excitation wavelength used for the cyclized reporter, the onset of fluo-rescence can be easily detected. This fluorescence-based detection method provides very high sensitivity and could enable rapid detection at permissible exposure levels. Tests with potential interferents show that the reporter is very selective, with responses from only a few highly toxic, electrophilic chemicals such as phosgene, thionyl chloride, and strong acids such as HF, HCl, and nitric acid. Dimethyl methyl phosphonate (DMMP), a common and inactive simu-lant for other CW detectors, is not reactive enough to generate a signal. The unique selectivity to chemical reactivity means that a highly toxic and hazardous chemical is present when the reporter responds and illustrates that this sensor can provide very low false alarm rates. Current efforts focus on demonstrating the sensitivity and range of agents and toxic industrial chemicals detected with this reporter as well as developing additional fluorescent reporters for a range of chemical reactivity classes. The goal is to produce a hand-held sensor that can sensitively detect a broad range of chemical warfare agent and toxic industrial chemical threats.

27 CFR 555.180 - Prohibitions relating to unmarked plastic explosives.

Code of Federal Regulations, 2014 CFR

2014-04-01

... person shall manufacture any plastic explosive that does not contain a detection agent. (b) No person..., receive, or possess any plastic explosive that does not contain a detection agent. This paragraph does not... Plastic Explosives means the Convention on the Marking of Plastic Explosives for the Purposes of Detection...

27 CFR 555.180 - Prohibitions relating to unmarked plastic explosives.

Code of Federal Regulations, 2012 CFR

2012-04-01

... person shall manufacture any plastic explosive that does not contain a detection agent. (b) No person..., receive, or possess any plastic explosive that does not contain a detection agent. This paragraph does not... Plastic Explosives means the Convention on the Marking of Plastic Explosives for the Purposes of Detection...

27 CFR 555.180 - Prohibitions relating to unmarked plastic explosives.

Code of Federal Regulations, 2013 CFR

2013-04-01

... person shall manufacture any plastic explosive that does not contain a detection agent. (b) No person..., receive, or possess any plastic explosive that does not contain a detection agent. This paragraph does not... Plastic Explosives means the Convention on the Marking of Plastic Explosives for the Purposes of Detection...

Utility of a prototype liposomal contrast agent for x-ray imaging of breast cancer: a proof of concept using micro-CT in small animals

NASA Astrophysics Data System (ADS)

Badea, C. T.; Samei, E.; Ghaghada, K.; Saunders, R.; Yuan, H.; Qi, Y.; Hedlund, L. W.; Mukundan, S.

2008-03-01

Imaging tumor angiogenesis in small animals is extremely challenging due to the size of the tumor vessels. Consequently, both dedicated small animal imaging systems and specialized intravascular contrast agents are required. The goal of this study was to investigate the use of a liposomal contrast agent for high-resolution micro-CT imaging of breast tumors in small animals. A liposomal blood pool agent encapsulating iodine with a concentration of 65.5 mg/ml was used with a Duke Center for In Vivo Microscopy (CIVM) prototype micro-computed tomography (micro-CT) system to image the R3230AC mammary carcinoma implanted in rats. The animals were injected with equivalent volume doses (0.02 ml/kg) of contrast agent. Micro-CT with the liposomal blood pool contrast agent ensured a signal difference between the blood and the muscle higher than 450 HU allowing the visualization of the tumors 3D vascular architecture in exquisite detail at 100-micron resolution. The micro-CT data correlated well with the histological examination of tumor tissue. We also studied the ability to detect vascular enhancement with limited angle based reconstruction, i.e. tomosynthesis. Tumor volumes and their regional vascular percentage were estimated. This imaging approach could be used to better understand tumor angiogenesis and be the basis for evaluating anti-angiogenic therapies.

A study on gaseous extinguishing agent sensing with a simple measurement method

NASA Astrophysics Data System (ADS)

Guan, Yu; Lu, Song; Yuan, Wei; Qian, Hanjie

2018-03-01

As research on the concentration distribution for evaluating the effectiveness of a gas fire extinguisher system is quite important, the proper sensing technology is necessary. Here, a simple method used for measuring the concentration of agent is introduced, and the manufacture of the sensing part is described clearly. The sensing unit is composed of a pressure reducing structure and pressure sensor element. The detection was achieved by sensing the change of pressure difference caused by gas flow. In order to verify the theory and characterize the sensing performance, two types of fire extinguishing agents, bromotrifluoromethane (CBrF3) and heptafluoropropane (C3HF7), were used in the experiments. The results showed a high sensitivity from 0 to 100%, good repeatability and fast response/recovery time. Furthermore, the effect of operating temperature, humidity and geometric structure on the response were investigated. Measurements showed, for CBrF3, that the temperature had a linear impact on the response and the influence of humidity in the sensor was negligible. Through the analysis of the geometry parameter, it was found that the sensing performance could be greatly improved through adjusting the geometry structure. This technique provides a low-cost and highly reliable sensor for the detection of gaseous extinguishing agent that can be easily fabricated.

Deterring Online Advertising Fraud through Optimal Payment in Arrears

NASA Astrophysics Data System (ADS)

Edelman, Benjamin

Online advertisers face substantial difficulty in selecting and supervising small advertising partners: Fraud can be well-hidden, and limited reputation systems reduce accountability. But partners are not paid until after their work is complete, and advertisers can extend this delay both to improve detection of improper partner practices and to punish partners who turn out to be rule-breakers. I capture these relationships in a screening model with delayed payments and probabilistic delayed observation of agents’ types. I derive conditions in which an advertising principal can set its payment delay to deter rogue agents and to attract solely or primarily good-type agents. Through the savings from excluding rogue agents, the principal can increase its profits while offering increased payments to good-type agents. I estimate that a leading affiliate network could have invoked an optimal payment delay to eliminate 71% of fraud without decreasing profit.

Aviation Engine Test Facilities (AETF) fire protection study

NASA Astrophysics Data System (ADS)

Beller, R. C.; Burns, R. E.; Leonard, J. T.

1989-07-01

An analysis is presented to the effectiveness of various types of fire fighting agents in extinguishing the kinds of fires anticipated in Aviation Engine Test Facilities (AETF), otherwise known as Hush Houses. The agents considered include Aqueous Film-Forming Foam, Halon 1301, Halon 1211 and water. Previous test work has shown the rapidity with which aircraft, especially high performance aircraft, can be damaged by fire. Based on this, tentative criteria for this evaluation included a maximum time of 20 s from fire detection to extinguishment and a period of 30 min in which the agent would prevent reignition. Other issues examined included: toxicity, corrosivity, ease of personnel egress, system reliability, and cost effectiveness. The agents were evaluated for their performance in several fire scenarios, including: under frame fire, major engine fire, engine disintegration fire, high-volume pool fire with simultaneous spill fire, internal electrical fire, and runaway engine fire.

Environmental factors associated with a spectrum of neurodevelopmental deficits.

PubMed

Mendola, Pauline; Selevan, Sherry G; Gutter, Suzanne; Rice, Deborah

2002-01-01

A number of environmental agents have been shown to demonstrate neurotoxic effects either in human or laboratory animal studies. Critical windows of vulnerability to the effects of these agents occur both pre- and postnatally. The nervous system is relatively unique in that different parts are responsible for different functional domains, and these develop at different times (e.g., motor control, sensory, intelligence and attention). In addition, the many cell types in the brain have different windows of vulnerability with varying sensitivities to environmental agents. This review focuses on two environmental agents, lead and methylmercury, to illustrate the neurobehavioral and cognitive effects that can result from early life exposures. Special attention is paid to distinguishing between the effects detected following episodes of poisoning and those detected following lower dose exposures. Perinatal and childhood exposure to high doses of lead results in encephalopathy and convulsions. Lower-dose lead exposures have been associated with impairment in intellectual function and attention. At high levels of prenatal exposure, methylmercury produces mental retardation, cerebral palsy and visual and auditory deficits in children of exposed mothers. At lower levels of methylmercury exposure, the effects in children have been more subtle. Other environmental neurotoxicants that have been shown to produce developmental neurotoxicity include polychlorinated biphenyls (PCBs), dioxins, pesticides, ionizing radiation, environmental tobacco smoke, and maternal use of alcohol, tobacco, marijuana and cocaine. Exposure to environmental agents with neurotoxic effects can result in a spectrum of adverse outcomes from severe mental retardation and disability to more subtle changes in function depending on the timing and dose of the chemical agent. Copyright 2002 Wiley-Liss, Inc.

Characteristics of Gadolinium Oxide Nanoparticles Using Terahertz Spectroscopy (abstract)

NASA Astrophysics Data System (ADS)

Lee, Dongkyu; Maeng, Inhee; Oh, Seung Jae; Kim, Taekhoon; Cho, Byung Kyu; Lee, Kwangyeol; Son, Joo-Hiuk

2009-04-01

The penetration property of the terahertz electromagnetic (THz) wave is relevant to its use. We used the THz wave spectroscopy system which easily penetrates some materials that do not contain water, e.g., plastic and ceramics. The system has been developed for several purposes, including measuring the properties of semiconductors and bio-materials, and detecting plastic bombs and ceramic knives at airports. It is also used for medical imaging systems, such as magnetic resonance imaging (MRI), at some research institutes. It can show not only the difference in amplitude, but also the difference of the phase of each point of sample. MRI technology usually uses contrast agents to enhance the quality of the image. Gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA), made with a heavy metal ion, is commonly used as a clinical MRI contrast agent. Gadolinium oxide (Gd2O3) nanoparticle is a new contrast agent. It serves to equip the core of each particle with antibodies or ligands. It can freely circulate in blood vessels without amassing in the liver or lungs. This study shows the characteristics of gadolinium oxide nanoparticles to further advance terahertz medical imaging.

A simplified building airflow model for agent concentration prediction.

PubMed

Jacques, David R; Smith, David A

2010-11-01

A simplified building airflow model is presented that can be used to predict the spread of a contaminant agent from a chemical or biological attack. If the dominant means of agent transport throughout the building is an air-handling system operating at steady-state, a linear time-invariant (LTI) model can be constructed to predict the concentration in any room of the building as a result of either an internal or external release. While the model does not capture weather-driven and other temperature-driven effects, it is suitable for concentration predictions under average daily conditions. The model is easily constructed using information that should be accessible to a building manager, supplemented with assumptions based on building codes and standard air-handling system design practices. The results of the model are compared with a popular multi-zone model for a simple building and are demonstrated for building examples containing one or more air-handling systems. The model can be used for rapid concentration prediction to support low-cost placement strategies for chemical and biological detection sensors.

Multiagent Work Practice Simulation: Progress and Challenges

NASA Technical Reports Server (NTRS)

Clancey, William J.; Sierhuis, Maarten; Shaffe, Michael G. (Technical Monitor)

2001-01-01

Modeling and simulating complex human-system interactions requires going beyond formal procedures and information flows to analyze how people interact with each other. Such work practices include conversations, modes of communication, informal assistance, impromptu meetings, workarounds, and so on. To make these social processes visible, we have developed a multiagent simulation tool, called Brahms, for modeling the activities of people belonging to multiple groups, situated in a physical environment (geographic regions, buildings, transport vehicles, etc.) consisting of tools, documents, and a computer system. We are finding many useful applications of Brahms for system requirements analysis, instruction, implementing software agents, and as a workbench for relating cognitive and social theories of human behavior. Many challenges remain for representing work practices, including modeling: memory over multiple days, scheduled activities combining physical objects, groups, and locations on a timeline (such as a Space Shuttle mission), habitat vehicles with trajectories (such as the Shuttle), agent movement in 3D space (e.g., inside the International Space Station), agent posture and line of sight, coupled movements (such as carrying objects), and learning (mimicry, forming habits, detecting repetition, etc.).

Multiagent Work Practice Simulation: Progress and Challenges

NASA Technical Reports Server (NTRS)

Clancey, William J.; Sierhuis, Maarten

2002-01-01

Modeling and simulating complex human-system interactions requires going beyond formal procedures and information flows to analyze how people interact with each other. Such work practices include conversations, modes of communication, informal assistance, impromptu meetings, workarounds, and so on. To make these social processes visible, we have developed a multiagent simulation tool, called Brahms, for modeling the activities of people belonging to multiple groups, situated in a physical environment (geographic regions, buildings, transport vehicles, etc.) consisting of tools, documents, and computer systems. We are finding many useful applications of Brahms for system requirements analysis, instruction, implementing software agents, and as a workbench for relating cognitive and social theories of human behavior. Many challenges remain for representing work practices, including modeling: memory over multiple days, scheduled activities combining physical objects, groups, and locations on a timeline (such as a Space Shuttle mission), habitat vehicles with trajectories (such as the Shuttle), agent movement in 3d space (e.g., inside the International Space Station), agent posture and line of sight, coupled movements (such as carrying objects), and learning (mimicry, forming habits, detecting repetition, etc.).

Fe3O4-based PLGA nanoparticles as MR contrast agents for the detection of thrombosis

PubMed Central

Liu, Jia; Xu, Jie; Zhou, Jun; Zhang, Yu; Guo, Dajing; Wang, Zhigang

2017-01-01

Thrombotic disease is a great threat to human health, and early detection is particularly important. Magnetic resonance (MR) molecular imaging provides noninvasive imaging with the potential for early disease diagnosis. In this study, we developed Fe3O4-based poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) surface-modified with a cyclic Arg-Gly-Asp (cRGD) peptide as an MR contrast agent for the detection of thrombosis. The physical and chemical characteristics, biological toxicity, ability to target thrombi, and biodistribution of the NPs were studied. The Fe3O4-PLGA-cRGD NPs were constructed successfully, and hematologic and pathologic assays indicated no in vivo toxicity of the NPs. In a rat model of FeCl3-induced abdominal aorta thrombosis, the NPs readily and selectively accumulated on the surface of the thrombosis and under vascular endothelial cells ex vivo and in vivo. In the in vivo experiment, the biodistribution of the NPs suggested that the NPs might be internalized by the macrophages of the reticuloendothelial system in the liver and the spleen. The T2 signal decreased at the mural thrombus 10 min after injection and then gradually increased until 50 min. These results suggest that the NPs are suitable for in vivo molecular imaging of thrombosis under high shear stress conditions and represent a very promising MR contrast agent for sensitive and specific detection of thrombosis. PMID:28223802

Single-layer and dual-layer contrast-enhanced mammography using amorphous selenium flat panel detectors

NASA Astrophysics Data System (ADS)

Allec, N.; Abbaszadeh, S.; Karim, K. S.

2011-09-01

The accumulation of injected contrast agents allows the image enhancement of lesions through the use of contrast-enhanced mammography. In this technique, the combination of two acquired images is used to create an enhanced image. There exist several methods to acquire the images to be combined, which include dual energy subtraction using a single detection layer that suffers from motion artifacts due to patient motion between image acquisition. To mitigate motion artifacts, a detector composed of two layers may be used to simultaneously acquire the low and high energy images. In this work, we evaluate both of these methods using amorphous selenium as the detection material to find the system parameters (tube voltage, filtration, photoconductor thickness and relative intensity ratio) leading to the optimal performance. We then compare the performance of the two detectors under the variation of contrast agent concentration, tumor size and dose. The detectability was found to be most comparable at the lower end of the evaluated factors. The single-layer detector not only led to better contrast, due to its greater spectral separation capabilities, but also had lower quantum noise. The single-layer detector was found to have a greater detectability by a factor of 2.4 for a 2.5 mm radius tumor having a contrast agent concentration of 1.5 mg ml-1 in a 4.5 cm thick 50% glandular breast. The inclusion of motion artifacts in the comparison is part of ongoing research efforts.

Single-layer and dual-layer contrast-enhanced mammography using amorphous selenium flat panel detectors.

PubMed

Allec, N; Abbaszadeh, S; Karim, K S

2011-09-21

The accumulation of injected contrast agents allows the image enhancement of lesions through the use of contrast-enhanced mammography. In this technique, the combination of two acquired images is used to create an enhanced image. There exist several methods to acquire the images to be combined, which include dual energy subtraction using a single detection layer that suffers from motion artifacts due to patient motion between image acquisition. To mitigate motion artifacts, a detector composed of two layers may be used to simultaneously acquire the low and high energy images. In this work, we evaluate both of these methods using amorphous selenium as the detection material to find the system parameters (tube voltage, filtration, photoconductor thickness and relative intensity ratio) leading to the optimal performance. We then compare the performance of the two detectors under the variation of contrast agent concentration, tumor size and dose. The detectability was found to be most comparable at the lower end of the evaluated factors. The single-layer detector not only led to better contrast, due to its greater spectral separation capabilities, but also had lower quantum noise. The single-layer detector was found to have a greater detectability by a factor of 2.4 for a 2.5 mm radius tumor having a contrast agent concentration of 1.5 mg ml(-1) in a 4.5 cm thick 50% glandular breast. The inclusion of motion artifacts in the comparison is part of ongoing research efforts.

A demonstrator for an integrated subway protection system

NASA Astrophysics Data System (ADS)

Detoma, E.; Capetti, P.; Casati, G.; Billington, S.

2008-04-01

In 2006 SEPA has carried on the installation and tests of a demonstrator for an integrated subway protection system at a new subway station in the Naples, Italy) metropolitan area. Protection of a subway system is a difficult task given the amount of passengers transported every day. The demonstrator has been limited to non-intrusive detection techniques not to impair the passenger flow into the station. The demonstrator integrates several technologies and products that have been developed by SEPA or are already available on the market (MKS Instruments,...). The main purpose is to provide detection capabilities for attempts to introduce radioactive substances in the subway station, in order to foil possible attempts to place a dirty bomb, and threat detection and identification following release of chemical agents. The system integrates additional sensors such as video surveillance cameras and air flow sensing to complement the basic sensors suite. The need to protect sensitive installations such as subway stations has been highlighted by the series of terroristics actions carried out in recent years in the subway in London. However, given the number of passengers of a metro system, it is impossible to propose security techniques operating in ways similar to the screening of passengers in airports. Passengers screening and threat detection and identification must be quick, non-intrusive and capable of screening a large number of passengers to be applicable to mass transit systems. In 2005 SEPA, a small company operating in the field of trains video-surveillance systems and radiation detectors, started developing an integrated system to provide a comprehensive protection to subway stations, based on ready available or off-the-shelf components in order to quickly develop a reliable system with available technology. We ruled out at the beginning any new development in order to speed up the fielding of the system in less than one year. The system was developed with commercial sensors and deployed in a new station of the Naples metropolitan transit system in Mugnano. The station was particularly suitable for the demonstration since it is a new station that includes air venting control, water barriers (for fire and smoke containment) and a complete SCADA system to integrate technical and video surveillance operations. In order to protect the subway, we tackled four basic technologies, all readily available in-house or on the market: - radiation detection, to detect the introduction in the station of radionuclides, that may be dispersed by conventional explosive (a "dirty" bomb); - chemical agents detection and identification (after release), complemented with air speed and velocity sensors to estimate, track and predict the contamination plume; - video surveillance, integrated with the SCADA system and already available in the station.

Comparison of traditional and molecular analytical methods for detecting biological agents in raw and drinking water following ultrafiltration

USGS Publications Warehouse

Francy, D.S.; Bushon, R.N.; Brady, A.M.G.; Bertke, E.E.; Kephart, C.M.; Likirdopulos, C.A.; Mailot, B.E.; Schaefer, F. W.; Lindquist, H.D. Alan

2009-01-01

Aims: To compare the performance of traditional methods to quantitative polymerase chain reaction (qPCR) for detecting five biological agents in large-volume drinking-water samples concentrated by ultrafiltration (UF). Methods and Results: Drinking-water samples (100 l) were seeded with Bacillus anthracis, Cryptospordium parvum, Francisella tularensis, Salmonella Typhi, and Vibrio cholerae and concentrated by UF. Recoveries by traditional methods were variable between samples and between some replicates; recoveries were not determined by qPCR. Francisella tularensis and V. cholerae were detected in all 14 samples after UF, B. anthracis was detected in 13, and C. parvum was detected in 9 out of 14 samples. Numbers found by qPCR after UF were significantly or nearly related to those found by traditional methods for all organisms except for C. parvum. A qPCR assay for S. Typhi was not available. Conclusions: qPCR can be used to rapidly detect biological agents after UF as well as traditional methods, but additional work is needed to improve qPCR assays for several biological agents, determine recoveries by qPCR, and expand the study to other areas. Significance and Impact of the Study: To our knowledge, this is the first study to compare the use of traditional and qPCR methods to detect biological agents in large-volume drinking-water samples. ?? 2009 The Society for Applied Microbiology.

SU-E-I-84: MRI Relaxation Properties of a Pre-Clinical Hypoxia-Sensitive MRI Contrast Agent

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yee, S; Wilson, G; Chavez, F

2014-06-01

Purpose: A possible hypoxia-sensitive MRI agent, hexamethyldisiloxane (HMDSO), has been tried to image oxygen level in proton-based MRI (Kodibagkar et al, NMR Biomed, 2008). The induced changes of T1 (or R1) value by the HMDSO as the oxygenation level changes are the principle that the hypoxia agent is based on: the R1 increases as the oxygen level increases. However, as reported previously, the range of R1 values (0.1–0.3 s-1, corresponding to 3–10 s of T1) is not in the range where a regular MRI technique can easily detect the change. In order for this agent to be widely applied inmore » an MRI environment, more relaxation properties of this agent, including T1 in the rotating frame (T1rho) and T2, need to be explored. Here, the relaxation properties of this agent are explored. Methods: A phantom was made with HMDSO, water and mineral oil, each of which was prepared with oxygen and nitrogen, and was imaged in a 3T MRI system. The T1 properties were explored by the inversion recovery (TR=3000ms, TE=65ms) while varying the inversion time (TI), and also by the fast-field-echo (TR=2 ms, TE=2.8ms) while varying the flip angle (FA). T1rho was explored with a 5-pulse spin-locking technique (TR=5000ms, TE=10ms, spin-lock field=500Hz) while varying the spin-lock duration. T2 was explored with multi-shot TSE (TR=2500ms) while varying TE. Results: With the variable FA and TI, the signals of HMDSO with oxygen and nitrogen change in a similar way and do not respond well by the change of oxygen level, which confirms the large T1 value of HMDSO. The T1rho and T2, however, have a better sensitivity. Conclusion: For the possible pre-clinical hypoxia MRI agent (HMDSO), the detection of T1 (or R1) changes may be more challenging than the detection of other relaxation properties, particularly T2, as the oxygen level changes.« less

Controllable assembly and disassembly of nanoparticle systems via protein and DNA agents

DOEpatents

Lee, Soo-Kwan; Gang, Oleg; van der Lelie, Daniel

2014-05-20

The invention relates to the use of peptides, proteins, and other oligomers to provide a means by which normally quenched nanoparticle fluorescence may be recovered upon detection of a target molecule. Further, the inventive technology provides a structure and method to carry out detection of target molecules without the need to label the target molecules before detection. In another aspect, a method for forming arbitrarily shaped two- and three-dimensional protein-mediated nanoparticle structures and the resulting structures are described. Proteins mediating structure formation may themselves be functionalized with a variety of useful moieties, including catalytic functional groups.

Distributed Intrusion Detection for Computer Systems Using Communicating Agents

DTIC Science & Technology

2000-01-01

Log for a variety of suspicious events (like repeated failed login attempts), and alerts the IDAgent processes immediately via pipes when it finds...UX, IBM LAN Server, Raptor Eagle Firewalls, ANS Interlock Firewalls, and SunOS BSM. This program appears to be robust across many platforms. EMERALD ...Neumann, 1999] is a system developed by SRI International with research funding from DARPA. The EMERALD project will be the successor to Next

Electrophysiological and Electrochemical Methods Development for the Detection of Biologically Active Chemical Agents

DTIC Science & Technology

1988-11-01

Bilayer ........................................... 14 5. Current-Voltage Curve for Gramacidin in a Lecithin -Sphingomyelin Patch Bilayer... lecithin (Avanti). 9 2. MATERIALS 2.1 Patch Microprobe Instrumentation. The basis of the microprobe system is an AxoPatch Patch- Clamping Amplifier System...histogram of 1024 events cut above 2 pA. Events sampled are thought to be from the same single gramacidin channel in a lecithin : sphingomyelin (5:1) patch

High-sensitivity, high-selectivity detection of chemical warfare agents

NASA Astrophysics Data System (ADS)

Pushkarsky, Michael B.; Webber, Michael E.; Macdonald, Tyson; Patel, C. Kumar N.

2006-01-01

We report high-sensitivity detection of chemical warfare agents (nerve gases) with very low probability of false positives (PFP). We demonstrate a detection threshold of 1.2ppb (7.7μg/m3 equivalent of Sarin) with a PFP of <1:106 in the presence of many interfering gases present in an urban environment through the detection of diisopropyl methylphosphonate, an accepted relatively harmless surrogate for the nerve agents. For the current measurement time of ˜60s, a PFP of 1:106 corresponds to one false alarm approximately every 23months. The demonstrated performance satisfies most current homeland and military security requirements.

Disposable pen-shaped capillary gel electrophoresis cartridge for fluorescence detection of bio-molecules

NASA Astrophysics Data System (ADS)

Amirkhanian, Varoujan; Tsai, Shou-Kuan

2014-03-01

We introduce a novel and cost-effective capillary gel electrophoresis (CGE) system utilizing disposable pen-shaped gelcartridges for highly efficient, high speed, high throughput fluorescence detection of bio-molecules. The CGE system has been integrated with dual excitation and emission optical-fibers with micro-ball end design for fluorescence detection of bio-molecules separated and detected in a disposable pen-shaped capillary gel electrophoresis cartridge. The high-performance capillary gel electrophoresis (CGE) analyzer has been optimized for glycoprotein analysis type applications. Using commercially available labeling agent such as ANTS (8-aminonapthalene-1,3,6- trisulfonate) as an indicator, the capillary gel electrophoresis-based glycan analyzer provides high detection sensitivity and high resolving power in 2-5 minutes of separations. The system can hold total of 96 samples, which can be automatically analyzed within 4-5 hours. This affordable fiber optic based fluorescence detection system provides fast run times (4 minutes vs. 20 minutes with other CE systems), provides improved peak resolution, good linear dynamic range and reproducible migration times, that can be used in laboratories for high speed glycan (N-glycan) profiling applications. The CGE-based glycan analyzer will significantly increase the pace at which glycoprotein research is performed in the labs, saving hours of preparation time and assuring accurate, consistent and economical results.

Handheld hyperspectral imager for standoff detection of chemical and biological aerosols

NASA Astrophysics Data System (ADS)

Hinnrichs, Michele; Jensen, James O.; McAnally, Gerard

2004-02-01

Pacific Advanced Technology has developed a small hand held imaging spectrometer, Sherlock, for gas leak and aerosol detection and imaging. The system is based on a patent technique that uses diffractive optics and image processing algorithms to detect spectral information about objects in the scene of the camera (IMSS Image Multi-spectral Sensing). This camera has been tested at Dugway Proving Ground and Dstl Porton Down facility looking at Chemical and Biological agent simulants. The camera has been used to investigate surfaces contaminated with chemical agent simulants. In addition to Chemical and Biological detection the camera has been used for environmental monitoring of green house gases and is currently undergoing extensive laboratory and field testing by the Gas Technology Institute, British Petroleum and Shell Oil for applications for gas leak detection and repair. The camera contains an embedded Power PC and a real time image processor for performing image processing algorithms to assist in the detection and identification of gas phase species in real time. In this paper we will present an over view of the technology and show how it has performed for different applications, such as gas leak detection, surface contamination, remote sensing and surveillance applications. In addition a sampling of the results form TRE field testing at Dugway in July of 2002 and Dstl at Porton Down in September of 2002 will be given.

Fast Flux Watch: A mechanism for online detection of fast flux networks.

PubMed

Al-Duwairi, Basheer N; Al-Hammouri, Ahmad T

2014-07-01

Fast flux networks represent a special type of botnets that are used to provide highly available web services to a backend server, which usually hosts malicious content. Detection of fast flux networks continues to be a challenging issue because of the similar behavior between these networks and other legitimate infrastructures, such as CDNs and server farms. This paper proposes Fast Flux Watch (FF-Watch), a mechanism for online detection of fast flux agents. FF-Watch is envisioned to exist as a software agent at leaf routers that connect stub networks to the Internet. The core mechanism of FF-Watch is based on the inherent feature of fast flux networks: flux agents within stub networks take the role of relaying client requests to point-of-sale websites of spam campaigns. The main idea of FF-Watch is to correlate incoming TCP connection requests to flux agents within a stub network with outgoing TCP connection requests from the same agents to the point-of-sale website. Theoretical and traffic trace driven analysis shows that the proposed mechanism can be utilized to efficiently detect fast flux agents within a stub network.

Detection of the agents of human ehrlichioses in ixodid ticks from California.

PubMed

Kramer, V L; Randolph, M P; Hui, L T; Irwin, W E; Gutierrez, A G; Vugia, D J

1999-01-01

A study was conducted in northern California to estimate the prevalence and distribution in ixodid ticks of the rickettsial agents of human monocytic (HME) and human granulocytic (HGE) ehrlichioses. More than 650 ixodid ticks were collected from 17 sites in six California counties over a 15-month period. Ehrlichia chaffeensis, the causative agent of HME, was detected by a nested polymerase chain reaction (PCR) in Ixodes pacificus (minimum infection rate [MIR] = 13.3%) and Dermacentor variabilis (infection rate=20.0%) from a municipal park in Santa Cruz County. The HGE agent was detected by nested PCR in I. pacificus adults from a heavily used recreational area in Alameda County (MIR = 4.7%) and a semirural community in Sonoma County (MIR = 6.7%). Evidence of infection with Ehrlichia spp. was not detected in D. occidentalis adults or I. pacificus nymphs. This study represents the first detection of E. chaffeensis in California ticks and the first report of infection in Ixodes spp. The competency of I. pacificus to be coinfected with and to transmit multiple disease agents, including those of human ehrlichioses and Lyme disease, has yet to be determined.

A novel sensitive pathogen detection system based on Microbead Quantum Dot System.

PubMed

Wu, Tzong-Yuan; Su, Yi-Yu; Shu, Wei-Hsien; Mercado, Augustus T; Wang, Shi-Kwun; Hsu, Ling-Yi; Tsai, Yow-Fu; Chen, Chung-Yung

2016-04-15

A fast and accurate detection system for pathogens can provide immediate measurements for the identification of infectious agents. Therefore, the Microbead Quantum-dots Detection System (MQDS) was developed to identify and measure target DNAs of pathogenic microorganisms and eliminated the need of PCR amplifications. This nanomaterial-based technique can detect different microorganisms by flow cytometry measurements. In MQDS, pathogen specific DNA probes were designed to form a hairpin structure and conjugated on microbeads. In the presence of the complementary target DNA sequence, the probes will compete for binding with the reporter probes but will not interfere with the binding between the probe and internal control DNA. To monitor the binding process by flow cytometry, both the reporter probes and internal control probes were conjugated with Quantum dots that fluoresce at different emission wavelengths using the click reaction. When MQDS was used to detect the pathogens in environmental samples, a high correlation coefficient (R=0.994) for Legionella spp., with a detection limit of 0.1 ng of the extracted DNAs and 10 CFU/test, can be achieved. Thus, this newly developed technique can also be applied to detect other pathogens, particularly viruses and other genetic diseases. Copyright © 2015 Elsevier B.V. All rights reserved.

Leptospirosis from water sources

PubMed Central

Wynwood, Sarah Jane; Graham, Glenn Charles; Weier, Steven Lance; Collet, Trudi Anne; McKay, David Brian; Craig, Scott Benjamin

2014-01-01

Leptospirosis outbreaks have been associated with many common water events including water consumption, water sports, environmental disasters, and occupational exposure. The ability of leptospires to survive in moist environments makes them a high-risk agent for infection following contact with any contaminated water source. Water treatment processes reduce the likelihood of leptospirosis or other microbial agents causing infection provided that they do not malfunction and the distribution networks are maintained. Notably, there are many differences in water treatment systems around the world, particularly between developing and developed countries. Detection of leptospirosis in water samples is uncommonly performed by molecular methods. PMID:25348115

Method and system for real-time analysis of biosensor data

DOEpatents

Greenbaum, Elias; Rodriguez, Jr., Miguel

2014-08-19

A method of biosensor-based detection of toxins includes the steps of providing a fluid to be analyzed having a plurality of photosynthetic organisms therein, wherein chemical, biological or radiological agents alter a nominal photosynthetic activity of the photosynthetic organisms. At a first time a measured photosynthetic activity curve is obtained from the photosynthetic organisms. The measured curve is automatically compared to a reference photosynthetic activity curve to determine differences therebetween. The presence of the chemical, biological or radiological agents, or precursors thereof, are then identified if present in the fluid using the differences.

‘Lowering the threshold of effective deterrence’—Testing the effect of private security agents in public spaces on crime: A randomized controlled trial in a mass transit system

PubMed Central

Bland, Matthew; Sutherland, Alex

2017-01-01

Supplementing local police forces is a burgeoning multibillion-dollar private security industry. Millions of formal surveillance agents in public settings are tasked to act as preventative guardians, as their high visibility presence is hypothesized to create a deterrent threat to potential offenders. Yet, rigorous evidence is lacking. We randomly assigned all train stations in the South West of England that experienced crime into treatment and controls conditions over a six-month period. Treatment consisted of directed patrol by uniformed, unarmed security agents. Hand-held trackers on every agent yielded precise measurements of all patrol time in the stations. Count-based regression models, estimated marginal means and odds-ratios are used to assess the effect of these patrols on crimes reported to the police by victims, as well as new crimes detected by police officers. Outcomes are measured at both specified target locations to which security guards were instructed to attend, as well as at the entire station complexes. Analyses show that 41% more patrol visits and 29% more minutes spent by security agents at treatment compared to control stations led to a significant 16% reduction in victim-generated crimes at the entirety of the stations’ complexes, with a 49% increase in police-generated detections at the target locations. The findings illustrate the efficacy of private policing for crime prevention theory. PMID:29211735

Diagnostic Assay for Rickettsia japonica

PubMed Central

Hanaoka, Nozomu; Matsutani, Minenosuke; Kawabata, Hiroki; Yamamoto, Seigo; Fujita, Hiromi; Sakata, Akiko; Azuma, Yoshinao; Ogawa, Motohiko; Takano, Ai; Watanabe, Haruo; Kishimoto, Toshio; Shirai, Mutsunori; Kurane, Ichiro

2009-01-01

We developed a specific and rapid detection system for Rickettsia japonica and R. heilongjiangensis, the causative agents of spotted fever, using a TaqMan minor groove binder probe for a particular open reading frame (ORF) identified by the R. japonica genome project. The target ORF was present only in R. japonica–related strains. PMID:19961684

The effect of triclosan on the uterotrophic response to extended doses of ethinyl estradiol in the weanling rat

EPA Science Inventory

Triclosan (TCS), a broad-spectrum antimicrobial agent found in many personal care products, has been detected in humans and has been shown to interact with endocrine systems in rats. We previously reported that TCS potentiated the estrogenic effect of ethinyl estradiol (EE) on u...

[The error analysis and experimental verification of laser radar spectrum detection and terahertz time domain spectroscopy].

PubMed

Liu, Wen-Tao; Li, Jing-Wen; Sun, Zhi-Hui

2010-03-01

Terahertz waves (THz, T-ray) lie between far-infrared and microwave in electromagnetic spectrum with frequency from 0.1 to 10 THz. Many chemical agent explosives show characteristic spectral features in the terahertz. Compared with conventional methods of detecting a variety of threats, such as weapons and chemical agent, THz radiation is low frequency and non-ionizing, and does not give rise to safety concerns. The present paper summarizes the latest progress in the application of terahertz time domain spectroscopy (THz-TDS) to chemical agent explosives. A kind of device on laser radar detecting and real time spectrum measuring was designed which measures the laser spectrum on the bases of Fourier optics and optical signal processing. Wedge interferometer was used as the beam splitter to wipe off the background light and detect the laser and measure the spectrum. The result indicates that 10 ns laser radar pulse can be detected and many factors affecting experiments are also introduced. The combination of laser radar spectrum detecting, THz-TDS, modern pattern recognition and signal processing technology is the developing trend of remote detection for chemical agent explosives.

Detection of early changes in lung cell cytology by flow-systems analysis techniques. Progress report, October 1, 1976--June 30, 1977. [Damage induced by exposure to toxic agents associated with production of synthetic fuels from oil shale and coal

DOE Office of Scientific and Technical Information (OSTI.GOV)

Steinkamp, J.A.; Hansen, K.M.; Wilson, J.S.

1977-07-01

This report summarizes results of continuing experiments to develop cytological and biochemical indicators for estimating damage to respiratory tract cells in animals exposed to toxic agents associated with production of synthetic fuels from oil shale and coal, the specific goal being the application of advanced flow-systems technologies to the detection of early atypical cellular changes in lung epithelium. The objectives of the program during the past 6 months were: to develop standard methods for lavaging lungs of several rodent species (hamster, rat, and mouse) to increase cell yield; initiate oil shale exposures in hamsters and rats; study the effects ofmore » macrophage mobility in the presence of oil shale; and determine the effects of different fixatives on lung cell morphology using electron microscopy. To develop standard methods for lavaging the respiratory tract of test animals, experiments were devised to increase cell yield with minimal debris and blood. Proteolytic enzymes such as trypsin were also tested but produced excessive amounts of fibrinated blood. Experimental animals were exposed to raw and spent oil shale particulates to determine if changes in lung cell differential counts and/or atypical cellular changes were noted. Since the multiparameter cell separator system was inoperative during this reporting period due to major modifications, including the addition of an uv krypton laser, emphasis was primarily on cytological techniques. As the flow-systems instrumentation becomes fully operational during the next month, automated analysis of respiratory tract cells and measurement of physical and biochemical properties as a function of exposure to toxic agents will continue.« less

Development of biosensors for the detection of biological warfare agents: its issues and challenges.

PubMed

Kumar, Harish; Rani, Renu

2013-01-01

This review discusses current development in biosensors for the detection of biological warfare agents (BWAs). BWAs include bacteria, virus and toxins that are added deliberately into air water and food to spread terrorism and cause disease or death. The rapid and unambiguous detection and identification of BWAs with early warning signals for detecting possible biological attack is a major challenge for government agencies particularly military and health. The detection devices--biosensors--can be classified (according to their physicochemical transducers) into four types: electrochemical, nucleic acid, optical and piezoelectric. Advantages and limitations of biosensors are discussed in this review followed by an assessment of the current state of development of different types of biosensors. The research and development in biosensors for biological warfare agent detection is of great interest for the public as well as for governments.

Nano-sized Contrast Agents to Non-Invasively Detect Renal Inflammation by Magnetic Resonance Imaging

PubMed Central

Thurman, Joshua M.; Serkova, Natalie J.

2013-01-01

Several molecular imaging methods have been developed that employ nano-sized contrast agents to detect markers of inflammation within tissues. Renal inflammation contributes to disease progression in a wide range of autoimmune and inflammatory diseases, and a biopsy is currently the only method of definitively diagnosing active renal inflammation. However, the development of new molecular imaging methods that employ contrast agents capable of detecting particular immune cells or protein biomarkers will allow clinicians to evaluate inflammation throughout the kidneys, and to assess a patient's response to immunomodulatory drugs. These imaging tools will improve our ability to validate new therapies and to optimize the treatment of individual patients with existing therapies. This review describes the clinical need for new methods of monitoring renal inflammation, and recent advances in the development of nano-sized contrast agents for detection of inflammatory markers of renal disease. PMID:24206601

Identification of V-type nerve agents in vapor samples using a field-portable capillary gas chromatography/membrane-interfaced electron ionization quadrupole mass spectrometry instrument with Tri-Bed concentrator and fluoridating conversion tube.

PubMed

Ohrui, Y; Nagoya, T; Kurimata, N; Sodeyama, M; Seto, Y

2017-07-01

A field-portable gas chromatography-mass spectrometry (GC-MS) system (Hapsite ER) was evaluated for the detection of nonvolatile V-type nerve agents (VX and Russian VX (RVX)) in the vapor phase. The Hapsite ER system consists of a Tri-Bed concentrator gas sampler, a nonpolar low thermal-mass capillary GC column and a hydrophobic membrane-interfaced electron ionization quadrupole mass spectrometer evacuated by a non-evaporative getter pump. The GC-MS system was attached to a VX-G fluoridating conversion tube containing silver nitrate and potassium fluoride. Sample vapors of VX and RVX were converted into O-ethyl methylphosphonofluoridate (EtGB) and O-isobutyl methylphosphonofluoridate (iBuGB), respectively. These fluoridated derivatives were detected within 10 min. No compounds were detected when the VX and RVX samples were analyzed without the conversion tube. A vapor sample of tabun (GA) was analyzed, in which GA and O-ethyl N,N-dimethylphosphoramidofluoridate were detected. The molar recovery percentages of EtGB and iBuGB from VX and RVX vapors varied from 0.3 to 17%, which was attributed to variations in the vaporization efficiency of the glass vapor container. The conversion efficiencies of the VX-G conversion tube for VX and RVX to their phosphonate derivatives were estimated to be 40%. VX and RVX vapors were detected at concentrations as low as 0.3 mg m -3 . Gasoline vapor was found to interfere with the analyses of VX and RVX. In the presence of 160 mg m -3 gasoline, the detection limits of VX and RVX vapor were increased to 20 mg m -3 . Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Fast and precise detection of ricin with microcapillary sensor system

NASA Astrophysics Data System (ADS)

Lee, Jun-Tae; Dosev, Dosi; Nichkova, Mikaela; Ma, Zhiya; Gee, Shirley; Hammock, Bruce D.; Kennedy, Ian M.

2009-02-01

Ricin is an easily available toxin which can be used as a bio-terror agent. Fast and inexpensive methods for its detection in different samples are needed. Recently we have developed a novel fluorescent sandwich immunoassay for ricin using magnetic-luminescent nanoparticles (MLNPs) as carriers in a microcapillary system for incubation and detection. Antiricin antibody coated MLNPs that were dispersed in buffer solution were introduced in the capillary tube and immobilized inside using an external electromagnet. Then the sample containing ricin was injected while the MLNPs were mixed by an alternating magnetic field. After the incubation, washing solution and secondary antibody conjugated with Alexa-fluorescent were injected into the capillary while the MLNPs were constantly mixed. After the final wash, the particles were immobilized for detection. The total analysis time was reduced to less than forty minutes which is about 8-10 fold improvement in comparison with the plate-based protocols. This system is promising for the development of a portable biosensor and can be used for the detection of other analytes of interest.

Doxycycline Inducible Melanogenic Vaccinia Virus as Theranostic Anti-Cancer Agent.

PubMed

Kirscher, Lorenz; Deán-Ben, Xosé Luis; Scadeng, Miriam; Zaremba, Angelika; Zhang, Qian; Kober, Christina; Fehm, Thomas Felix; Razansky, Daniel; Ntziachristos, Vasilis; Stritzker, Jochen; Szalay, Aladar A

2015-01-01

We reported earlier the diagnostic potential of a melanogenic vaccinia virus based system in magnetic resonance (MRI) and optoacoustic deep tissue imaging (MSOT). Since melanin overproduction lead to attenuated virus replication, we constructed a novel recombinant vaccinia virus strain (rVACV), GLV-1h462, which expressed the key enzyme of melanogenesis (tyrosinase) under the control of an inducible promoter-system. In this study melanin production was detected after exogenous addition of doxycycline in two different tumor xenograft mouse models. Furthermore, it was confirmed that this novel vaccinia virus strain still facilitated signal enhancement as detected by MRI and optoacoustic tomography. At the same time we demonstrated an enhanced oncolytic potential compared to the constitutively melanin synthesizing rVACV system.

Analysis of chemical warfare agents in food products by atmospheric pressure ionization-high field asymmetric waveform ion mobility spectrometry-mass spectrometry.

PubMed

Kolakowski, Beata M; D'Agostino, Paul A; Chenier, Claude; Mester, Zoltán

2007-11-01

Flow injection high field asymmetric waveform ion mobility spectrometry (FAIMS)-mass spectrometry (MS) methodology was developed for the detection and identification of chemical warfare (CW) agents in spiked food products. The CW agents, soman (GD), sarin (GB), tabun (GA), cyclohexyl sarin (GF), and four hydrolysis products, ethylphosphonic acid (EPA), methylphosphonic acid (MPA), pinacolyl methylphosphonic acid (Pin MPA), and isopropyl methylphosphonic acid (IMPA) were separated and detected by positive ion and negative ion atmospheric pressure ionization-FAIMS-MS. Under optimized conditions, the compensation voltages were 7.2 V for GD, 8.0 V for GA, 7.2 V for GF, 7.6 V for GB, 18.2 V for EPA, 25.9 V for MPA, -1.9 V for PinMPA, and +6.8 V for IMPA. Sample preparation was kept to a minimum, resulting in analysis times of 3 min or less per sample. The developed methodology was evaluated by spiking bottled water, canola oil, cornmeal, and honey samples at low microgram per gram (or microg/mL) levels with the CW agents or CW agent hydrolysis products. The detection limits observed for the CW agents in the spiked food samples ranged from 3 to 15 ng/mL in bottled water, 1-33 ng/mL in canola oil, 1-34 ng/g in cornmeal, and 13-18 ng/g in honey. Detection limits were much higher for the CW agent hydrolysis products, with only MPA being detected in spiked honey samples.

Normalization of test and evaluation of biothreat detection systems: overcoming microbial air content fluctuations by using a standardized reagent bacterial mixture.

PubMed

Berchebru, Laurent; Rameil, Pascal; Gaudin, Jean-Christophe; Gausson, Sabrina; Larigauderie, Guilhem; Pujol, Céline; Morel, Yannick; Ramisse, Vincent

2014-10-01

Test and evaluation of engineered biothreat agent detection systems ("biodetectors") are a challenging task for government agencies and industries involved in biosecurity and biodefense programs. In addition to user friendly features, biodetectors need to perform both highly sensitive and specific detection, and must not produce excessive false alerts. In fact, the atmosphere displays a number of variables such as airborne bacterial content that can interfere with the detection process, thus impeding comparative tests when carried out at different times or places. To overcome these bacterial air content fluctuations, a standardized reagent bacterial mixture (SRBM), consisting in a collection of selected cultivable environmental species that are prevalent in temperate climate bioaerosols, was designed to generate a stable, reproducible, and easy to use surrogate of bioaerosol sample. The rationale, design, and production process are reported. The results showed that 8.59; CI 95%: 8.46-8.72 log cfu distributed into vials underwent a 0.95; CI 95%: 0.65-1.26 log viability decay after dehydration and subsequent reconstitution, thus advantageously mimicking a natural bioaerosol sample which is typically composed of cultivable and uncultivable particles. Dehydrated SRBM was stable for more than 12months at 4°C and allowed the reconstitution of a dead/live cells aqueous suspension that is stable for 96h at +4°C, according to plate counts. Specific detection of a simulating biothreat agent (e.g. Bacillus atrophaeus) by immuno-magnetic or PCR assays did not display any significant loss of sensitivity, false negative or positive results in the presence of SRBM. This work provides guidance on testing and evaluating detection devices, and may contribute to the establishment of suitable standards and normalized procedures. Copyright © 2014 Elsevier B.V. All rights reserved.

Detection of human pathogenic Ehrlichia muris-like agent in Peromyscus leucopus.

PubMed

Castillo, Caroline G; Eremeeva, Marina E; Paskewitz, Susan M; Sloan, Lynne M; Lee, Xia; Irwin, William E; Tonsberg, Stefan; Pritt, Bobbi S

2015-03-01

An Ehrlichia muris-like (EML) bacterium was recently detected in humans and Ixodes scapularis ticks in Minnesota and Wisconsin. The reservoir for this agent is unknown. To investigate the occurrence of the EML agent, groEL PCR testing and sequencing was performed on blood from small mammals and white-tailed deer that were collected in areas where human and tick infections were previously demonstrated. DNA of the EML agent was detected in two Peromyscus leucopus of 146 small mammals (1.4%); while 181 O. virginianus tested negative. This report provides the first evidence that DNA from the EML agent is found in P. leucopus, the same animal that is a reservoir for Anaplasma phagocytophilum in this region. The role of white-tailed deer remains inconclusive. Further sampling is warranted to understand the spatial and temporal distribution, transmission and maintenance of this pathogen. Copyright © 2014 Elsevier GmbH. All rights reserved.

Neutron Interrogation System For Underwater Threat Detection And Identification

NASA Astrophysics Data System (ADS)

Barzilov, Alexander P.; Novikov, Ivan S.; Womble, Phil C.

2009-03-01

Wartime and terrorist activities, training and munitions testing, dumping and accidents have generated significant munitions contamination in the coastal and inland waters in the United States and abroad. Although current methods provide information about the existence of the anomaly (for instance, metal objects) in the sea bottom, they fail to identify the nature of the found objects. Field experience indicates that often in excess of 90% of objects excavated during the course of munitions clean up are found to be non-hazardous items (false alarm). The technology to detect and identify waterborne or underwater threats is also vital for protection of critical infrastructures (ports, dams, locks, refineries, and LNG/LPG). We are proposing a compact neutron interrogation system, which will be used to confirm possible threats by determining the chemical composition of the suspicious underwater object. The system consists of an electronic d-T 14-MeV neutron generator, a gamma detector to detect the gamma signal from the irradiated object and a data acquisition system. The detected signal then is analyzed to quantify the chemical elements of interest and to identify explosives or chemical warfare agents.

Interleukin 16- (IL-16-) Targeted Ultrasound Imaging Agent Improves Detection of Ovarian Tumors in Laying Hens, a Preclinical Model of Spontaneous Ovarian Cancer.

PubMed

Barua, Animesh; Yellapa, Aparna; Bahr, Janice M; Adur, Malavika K; Utterback, Chet W; Bitterman, Pincas; Basu, Sanjib; Sharma, Sameer; Abramowicz, Jacques S

2015-01-01

Limited resolution of transvaginal ultrasound (TVUS) scanning is a significant barrier to early detection of ovarian cancer (OVCA). Contrast agents have been suggested to improve the resolution of TVUS scanning. Emerging evidence suggests that expression of interleukin 16 (IL-16) by the tumor epithelium and microvessels increases in association with OVCA development and offers a potential target for early OVCA detection. The goal of this study was to examine the feasibility of IL-16-targeted contrast agents in enhancing the intensity of ultrasound imaging from ovarian tumors in hens, a model of spontaneous OVCA. Contrast agents were developed by conjugating biotinylated anti-IL-16 antibodies with streptavidin coated microbubbles. Enhancement of ultrasound signal intensity was determined before and after injection of contrast agents. Following scanning, ovarian tissues were processed for the detection of IL-16 expressing cells and microvessels. Compared with precontrast, contrast imaging enhanced ultrasound signal intensity significantly in OVCA hens at early (P < 0.05) and late stages (P < 0.001). Higher intensities of ultrasound signals in OVCA hens were associated with increased frequencies of IL-16 expressing cells and microvessels. These results suggest that IL-16-targeted contrast agents improve the visualization of ovarian tumors. The laying hen may be a suitable model to test new imaging agents and develop targeted anti-OVCA therapeutics.

VMSoar: a cognitive agent for network security

NASA Astrophysics Data System (ADS)

Benjamin, David P.; Shankar-Iyer, Ranjita; Perumal, Archana

2005-03-01

VMSoar is a cognitive network security agent designed for both network configuration and long-term security management. It performs automatic vulnerability assessments by exploring a configuration"s weaknesses and also performs network intrusion detection. VMSoar is built on the Soar cognitive architecture, and benefits from the general cognitive abilities of Soar, including learning from experience, the ability to solve a wide range of complex problems, and use of natural language to interact with humans. The approach used by VMSoar is very different from that taken by other vulnerability assessment or intrusion detection systems. VMSoar performs vulnerability assessments by using VMWare to create a virtual copy of the target machine then attacking the simulated machine with a wide assortment of exploits. VMSoar uses this same ability to perform intrusion detection. When trying to understand a sequence of network packets, VMSoar uses VMWare to make a virtual copy of the local portion of the network and then attempts to generate the observed packets on the simulated network by performing various exploits. This approach is initially slow, but VMSoar"s learning ability significantly speeds up both vulnerability assessment and intrusion detection. This paper describes the design and implementation of VMSoar, and initial experiments with Windows NT and XP.

Wireless sensors and sensor networks for homeland security applications.

PubMed

Potyrailo, Radislav A; Nagraj, Nandini; Surman, Cheryl; Boudries, Hacene; Lai, Hanh; Slocik, Joseph M; Kelley-Loughnane, Nancy; Naik, Rajesh R

2012-11-01

New sensor technologies for homeland security applications must meet the key requirements of sensitivity to detect agents below risk levels, selectivity to provide minimal false-alarm rates, and response speed to operate in high throughput environments, such as airports, sea ports, and other public places. Chemical detection using existing sensor systems is facing a major challenge of selectivity. In this review, we provide a brief summary of chemical threats of homeland security importance; focus in detail on modern concepts in chemical sensing; examine the origins of the most significant unmet needs in existing chemical sensors; and, analyze opportunities, specific requirements, and challenges for wireless chemical sensors and wireless sensor networks (WSNs). We further review a new approach for selective chemical sensing that involves the combination of a sensing material that has different response mechanisms to different species of interest, with a transducer that has a multi-variable signal-transduction ability. This new selective chemical-sensing approach was realized using an attractive ubiquitous platform of battery-free passive radio-frequency identification (RFID) tags adapted for chemical sensing. We illustrate the performance of RFID sensors developed in measurements of toxic industrial materials, humidity-independent detection of toxic vapors, and detection of chemical-agent simulants, explosives, and strong oxidizers.

Distributed reconfigurable control strategies for switching topology networked multi-agent systems.

PubMed

Gallehdari, Z; Meskin, N; Khorasani, K

2017-11-01

In this paper, distributed control reconfiguration strategies for directed switching topology networked multi-agent systems are developed and investigated. The proposed control strategies are invoked when the agents are subject to actuator faults and while the available fault detection and isolation (FDI) modules provide inaccurate and unreliable information on the estimation of faults severities. Our proposed strategies will ensure that the agents reach a consensus while an upper bound on the team performance index is ensured and satisfied. Three types of actuator faults are considered, namely: the loss of effectiveness fault, the outage fault, and the stuck fault. By utilizing quadratic and convex hull (composite) Lyapunov functions, two cooperative and distributed recovery strategies are designed and provided to select the gains of the proposed control laws such that the team objectives are guaranteed. Our proposed reconfigurable control laws are applied to a team of autonomous underwater vehicles (AUVs) under directed switching topologies and subject to simultaneous actuator faults. Simulation results demonstrate the effectiveness of our proposed distributed reconfiguration control laws in compensating for the effects of sudden actuator faults and subject to fault diagnosis module uncertainties and unreliabilities. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

Separation and detection of VX and its methylphosphonic acid degradation products on a microchip using indirect laser-induced fluorescence.

PubMed

Heleg-Shabtai, Vered; Gratziany, Natzach; Liron, Zvi

2006-05-01

The application of indirect LIF (IDLIF) technique for on-chip electrophoretic separation and detection of the nerve agent O-ethyl S-[2-(diisopropylamino)ethyl] methylphosphonothiolate (VX) and its major phosphonic degradation products, ethyl methylphosphonic acid (EMPA) and methylphosphonic acid (MPA) was demonstrated. Separation and detection of MPA degradation products of VX and the nerve agent isopropyl methylphosphonofluoridate (GB) are presented. The negatively charged dye eosin was found to be a good fluorescent marker for both the negatively charged phosphonic acids and the positively charged VX, and was chosen as the IDLIF visualization fluorescent dye. Separation and detection of VX, EMPA, and MPA in a simple-cross microchip were completed within less than a minute, and consumed only a 50 pL sample volume. A characteristic system peak that appeared in all IDLIF electropherograms served as an internal standard that increased the reliability of peak identification. The negative peak of both VX and the MPAs is in agreement with indirect detection theory and with previous reports in the literature. The LOD of VX and EMPA by IDLIF was 30 and 37 microM, respectively. Despite the fact that the detection sensitivity is relatively low, the rapid simultaneous on-chip analysis of both VX and its degradation products as well as the separation and detection of the MPA degradation products of both VX and GB, increases detection reliability and may present a choice when sensitivity is not critical compared with speed and simplicity of the assay.

APDS: the autonomous pathogen detection system.

PubMed

Hindson, Benjamin J; Makarewicz, Anthony J; Setlur, Ujwal S; Henderer, Bruce D; McBride, Mary T; Dzenitis, John M

2005-04-15

We have developed and tested a fully autonomous pathogen detection system (APDS) capable of continuously monitoring the environment for airborne biological threat agents. The system was developed to provide early warning to civilians in the event of a bioterrorism incident and can be used at high profile events for short-term, intensive monitoring or in major public buildings or transportation nodes for long-term monitoring. The APDS is completely automated, offering continuous aerosol sampling, in-line sample preparation fluidics, multiplexed detection and identification immunoassays, and nucleic acid-based polymerase chain reaction (PCR) amplification and detection. Highly multiplexed antibody-based and duplex nucleic acid-based assays are combined to reduce false positives to a very low level, lower reagent costs, and significantly expand the detection capabilities of this biosensor. This article provides an overview of the current design and operation of the APDS. Certain sub-components of the ADPS are described in detail, including the aerosol collector, the automated sample preparation module that performs multiplexed immunoassays with confirmatory PCR, and the data monitoring and communications system. Data obtained from an APDS that operated continuously for 7 days in a major U.S. transportation hub is reported.

Exposure of hospital workers to airborne antineoplastic agents

DOE Office of Scientific and Technical Information (OSTI.GOV)

deWerk Neal, A.; Wadden, R.A.; Chiou, W.L.

Practices for handling antineoplastic drugs were surveyed, and ambient-air sampling for four antineoplastic agents was conducted in outpatient oncology clinics. A questionnaire was administered in 1981 to the nurse or pharmacist in charge of drug preparation at 10 hospital oncology clinics. At three sites, air samples were collected during working hours in medication-preparation rooms and nearby offices. The air-sampling pumps contained filters at breathing-zone height; room air was drawn through each filter for 40 hours. Extracts from the filters were assayed by high-performance liquid chromatography (HPLC) for fluorouracil and cyclophosphamide in seven sets of samples and methotrexate and doxorubicin inmore » five sets of samples. Mass spectrometry (MS) was used to confirm detection of fluorouracil. Total use of each monitored drug was recorded at each site. Nine clinics had no ventilation hood, and drugs were prepared by nurses in eight clinics. Routine use of gloves (three clinics) and masks (one clinic) was uncommon, and wastes were disposed of in uncovered receptacles in four of the clinics. Eating and drinking occurred in seven of the preparation rooms. At the main air-sampling site, fluorouracil (0.12-82.26 ng/cu m) was detected in air during 200 of the 320 hours monitored. Cyclophosphamide (370 ng/cu m) was present during 80 hours. In the two other sites, fluorouracil was detected by HPLC but not confirmed by MS, and no cyclophosphamide was detected. No detectable amounts of methotrexate and doxorubicin were present. Fluorouracil was the most frequently used drug, and cyclophosphamide was second. Results suggest that personnel handling antineoplastic drugs are subject to potential systemic absorption of these agents by inhalation.« less

Western blot (immunoblot) assay of small, round-structured virus associated with an acute gastroenteritis outbreak in Tokyo.

PubMed

Hayashi, Y; Ando, T; Utagawa, E; Sekine, S; Okada, S; Yabuuchi, K; Miki, T; Ohashi, M

1989-08-01

Small, round-structured virus (SRSV) was detected in a stool specimen of a patient during an acute gastroenteritis outbreak in Tokyo and was tentatively named SRSV-9. SRSV-9 was purified by sucrose velocity gradient centrifugation after CsCl density gradient centrifugation. The buoyant density of SRSV-9 appeared to be 1.36 g/ml in CsCl. A Western blot (immunoblot) assay using the biotin-avidin system revealed that SRSV-9 was antigenically related to the Hawaii agent but distinct from the Norwalk agent and contained a single major structural protein with a molecular size of 63.0 +/- 0.6 kilodaltons. The prevalence of SRSV-9 infection in Tokyo was surveyed by the Western blot antibody assay by using a crude virus preparation as the antigen. Seroconversion was observed in 56.5% of the patients involved in the outbreaks from which SRSV was detected by electron microscopy.

Infrared point sensors for homeland defense applications

NASA Astrophysics Data System (ADS)

Thomas, Ross C.; Carter, Michael T.; Homrighausen, Craig L.

2004-03-01

We report recent progress toward the development of infrared point sensors for the detection of chemical warfare agents and explosive related chemicals, which pose a significant threat to both health and environment. Technical objectives have focused on the development of polymer sorbents to enhance the infrared response of these hazardous organic compounds. For example, infrared point sensors which part-per-billion detection limits have been developed that rapidlypartition chemical warfare agents and explosive related chemicals into polymer thin films with desirable chemical and physical properties. These chemical sensors demonstrate novel routes to reversible sensing of hazardous organic compounds. The development of small, low-power, sensitive, and selective instruments employing these chemical sensors would enhance the capabilities of federal, state, and local emergency response to incidents involving chemical terrorism. Specific applications include chemical defense systems for military personnel and homeland defense, environmental monitors for remediation and demilitarization, and point source detectors for emergency and maintenance response teams.

Federal Research and Development Funding: FY2010

DTIC Science & Technology

2009-11-23

represent the more research-oriented part of the RDT&E program. Budget activities 6.4 and 6.5 focus on the development of specific weapon systems or...to fund developmental testing of the BioWatch Generation 3 biological agent detection system. The Administration requested these funds for the...Acquisition, and Operations 800 826 825 844 856 Border and Maritime 33 40 40 40 44 Chemical and Biological 200 207 222 207 207 Command, Control, and

Optoacoustic sensing of ocular bacterial antigen using targeted gold nanorods

NASA Astrophysics Data System (ADS)

Maswadi, Saher; Page, Leland; Woodward, Lee; Glickman, Randolph D.; Barsalou, Norman

2008-02-01

Bacterial contamination can be detected using a minimally invasive optical method, based on laser-induced optoacoustic spectroscopy, to probe for specific antigens associated with a specific infectious agent. As a model system, we have used a surface antigen (Ag), isolated from Chlamydia trachomatis, and a complementary antibody (Ab). A preparation of 0.2 mg/ml of monoclonal Ab specific to the C. trachomatis surface Ag was conjugated to gold nanorods using standard commercial reagents, in order to produce a targeted contrast agent with a strong optoacoustic signal. The C. trachomatis Ag was absorbed in standard plastic microwells, and the binding of the complementary Ab-nanorod conjugate was tested in an immunoaffinity assay. Optoacoustic signals were elicited from the bound nanorods, using an optical parametric oscillator (OPO) laser system as the optical pump. The wavelength tuneability of the OPO optimized the spectroscopic measurement by exciting the nanorods at their optical absorption maxima. Optoacoustic responses were measured in the microwells using a probe beam deflection technique. Immunoaffinity assays were performed on several dilutions of purified C. trachomatis antigen ranging from 50 μg/ml to 1 pg/ml, in order to determine the detection limit for the optoacoustic-based assay. Only when the antigen was present, and the complementary Ab-NR reagent was introduced into the microwell, was an enhanced optoacoustic signal obtained, which indicated specific binding of the Ab-NR complex. The limit of detection with the current system design is between 1 and 5 pg/ml of bacterial Ag.

Detection of proteins and bacteria using an array of feedback capacitance sensors.

PubMed

Mehta, Manav; Hanumanthaiah, Chandra Sekar; Betala, Pravin Ajitkumar; Zhang, Hong; Roh, SaeWeon; Buttner, William; Penrose, William R; Stetter, Joseph R; Pérez-Luna, Victor H

2007-12-15

An integrated array of micron-dimension capacitors, originally developed for biometric applications (fingerprint identification), was engineered for detection of biological agents such as proteins and bacteria. This device consists of an array of 93,184 (256 x 364) individual capacitor-based sensing elements located underneath a thin (0.8 microm) layer of glass. This glass layer can be functionalized with organosilane-based monolayers to provide groups amenable for the immobilization of bioreceptors such as antibodies, enzymes, peptides, aptamers, and nucleotides. Upon functionalization with antibodies and in conjunction with signal amplification schemes that result in perturbation of the dielectric constant around the captured antigens, this system can be used as a detector of biological agents. Two signal amplification schemes were tested in this work: one consisted of 4 microm diameter latex immunobeads and a second one was based on colloidal gold catalyzed reduction of silver. These signal amplification approaches were demonstrated and show that this system is capable of specific detection of bacteria (Escherichia coli) and proteins (ovalbumin). The present work shows proof-of-principle demonstration that a simple fingerprint detector based on feedback capacitance measurements can be implemented as a biosensor. The approach presented could be easily expanded to simultaneously test for a large number of analytes and multiple samples given that this device has a large number of detectors. The device and required instrumentation is highly portable and does not require expensive and bulky instrumentation because it relies purely on electronic detection.

High-level specification of a proposed information architecture for support of a bioterrorism early-warning system.

PubMed

Berkowitz, Murray R

2013-01-01

Current information systems for use in detecting bioterrorist attacks lack a consistent, overarching information architecture. An overview of the use of biological agents as weapons during a bioterrorist attack is presented. Proposed are the design, development, and implementation of a medical informatics system to mine pertinent databases, retrieve relevant data, invoke appropriate biostatistical and epidemiological software packages, and automatically analyze these data. The top-level information architecture is presented. Systems requirements and functional specifications for this level are presented. Finally, future studies are identified.

Investigations of chemical warfare agents and toxic industrial compounds with proton-transfer-reaction mass spectrometry for a real-time threat monitoring scenario.

PubMed

Kassebacher, Thomas; Sulzer, Philipp; Jürschik, Simone; Hartungen, Eugen; Jordan, Alfons; Edtbauer, Achim; Feil, Stefan; Hanel, Gernot; Jaksch, Stefan; Märk, Lukas; Mayhew, Chris A; Märk, Tilmann D

2013-01-30

Security and protection against terrorist attacks are major issues in modern society. One especially challenging task is the monitoring and protection of air conditioning and heating systems of buildings against terrorist attacks with toxic chemicals. As existing technologies have low selectivity, long response times or insufficient sensitivity, there is a need for a novel approach such as we present here. We have analyzed various chemical warfare agents (CWAs) and/or toxic industrial compounds (TICs) and related compounds, namely phosgene, diphosgene, chloroacetone, chloroacetophenone, diisopropylaminoethanol, and triethyl phosphate, utilizing a high-resolution proton-transfer-reaction time-of-flight mass spectrometry (PTR-TOFMS) instrument with the objective of finding key product ions and their intensities, which will allow a low-resolution quadrupole mass spectrometry based PTR-MS system to be used with high confidence in the assignment of threat agents in the atmosphere. We obtained high accuracy PTR-TOFMS mass spectra of the six compounds under study at two different values for the reduced electric field in the drift tube (E/N). From these data we have compiled a table containing product ions, and isotopic and E/N ratios for highly selective threat compound detection with a compact and cost-effective quadrupole-based PTR-MS instrument. Furthermore, using chloroacetophenone (tear gas), we demonstrated that this instrument's response is highly linear in the concentration range of typical Acute Exposure Guideline Levels (AEGLs). On the basis of the presented results it is possible to develop a compact and cost-effective PTR-QMS instrument that monitors air supply systems and triggers an alarm as soon as the presence of a threat agent is detected. We hope that this real-time surveillance device will help to seriously improve safety and security in environments vulnerable to terrorist attacks with toxic chemicals. Copyright © 2012 John Wiley & Sons, Ltd.

A Miniaturized Colorimeter with a Novel Design and High Precision for Photometric Detection.

PubMed

Yan, Jun-Chao; Chen, Yan; Pang, Yu; Slavik, Jan; Zhao, Yun-Fei; Wu, Xiao-Ming; Yang, Yi; Yang, Si-Fan; Ren, Tian-Ling

2018-03-08

Water quality detection plays an increasingly important role in environmental protection. In this work, a novel colorimeter based on the Beer-Lambert law was designed for chemical element detection in water with high precision and miniaturized structure. As an example, the colorimeter can detect phosphorus, which was accomplished in this article to evaluate the performance. Simultaneously, a modified algorithm was applied to extend the linear measurable range. The colorimeter encompassed a near infrared laser source, a microflow cell based on microfluidic technology and a light-sensitive detector, then Micro-Electro-Mechanical System (MEMS) processing technology was used to form a stable integrated structure. Experiments were performed based on the ammonium molybdate spectrophotometric method, including the preparation of phosphorus standard solution, reducing agent, chromogenic agent and color reaction. The device can obtain a wide linear response range (0.05 mg/L up to 7.60 mg/L), a wide reliable measuring range up to 10.16 mg/L after using a novel algorithm, and a low limit of detection (0.02 mg/L). The size of flow cell in this design is 18 mm × 2.0 mm × 800 μm, obtaining a low reagent consumption of 0.004 mg ascorbic acid and 0.011 mg ammonium molybdate per determination. Achieving these advantages of miniaturized volume, high precision and low cost, the design can also be used in automated in situ detection.

A Miniaturized Colorimeter with a Novel Design and High Precision for Photometric Detection

PubMed Central

Chen, Yan; Pang, Yu; Slavik, Jan; Zhao, Yun-Fei; Wu, Xiao-Ming; Yang, Yi; Yang, Si-Fan; Ren, Tian-Ling

2018-01-01

Water quality detection plays an increasingly important role in environmental protection. In this work, a novel colorimeter based on the Beer-Lambert law was designed for chemical element detection in water with high precision and miniaturized structure. As an example, the colorimeter can detect phosphorus, which was accomplished in this article to evaluate the performance. Simultaneously, a modified algorithm was applied to extend the linear measurable range. The colorimeter encompassed a near infrared laser source, a microflow cell based on microfluidic technology and a light-sensitive detector, then Micro-Electro-Mechanical System (MEMS) processing technology was used to form a stable integrated structure. Experiments were performed based on the ammonium molybdate spectrophotometric method, including the preparation of phosphorus standard solution, reducing agent, chromogenic agent and color reaction. The device can obtain a wide linear response range (0.05 mg/L up to 7.60 mg/L), a wide reliable measuring range up to 10.16 mg/L after using a novel algorithm, and a low limit of detection (0.02 mg/L). The size of flow cell in this design is 18 mm × 2.0 mm × 800 μm, obtaining a low reagent consumption of 0.004 mg ascorbic acid and 0.011 mg ammonium molybdate per determination. Achieving these advantages of miniaturized volume, high precision and low cost, the design can also be used in automated in situ detection. PMID:29518059

The development of GADD45α luciferase reporter assays in human cells for assessing the genotoxicity of environmental pollutants.

PubMed

Xin, Lili; Wang, Jianshu; Wu, Yanhu; Guo, Sifan

2015-02-01

In order to assess the potential carcinogenic and genotoxic responses induced by environmental pollutants, genotoxicity test systems based on a GADD45α promoter-driven luciferase reporter in human A549 and HepG2 cells were established. Four different types of environmental toxicants including DNA alkylating agents, precarcinogenic agents, DNA cross-linking agents and non-carcinogenic agents, and three environmental samples collected from a coke oven plant were used to evaluate the test systems. After treated with the tested agents and environmental samples for 12 h, the cell viabilities and luciferase activities of the luciferase reporter cells were determined, respectively. Methyl methanesulfonate, benzo[a]pyrene, formaldehyde and the extractable organic matter (EOM) from coke oven emissions in ambient air generally produced significant induction of relative luciferase activity in a similar dose-dependent manner in A549- and HepG2-luciferase cells. No significant increases in relative luciferase activity were observed in pyrene-treated A549- or HepG2-luciferase cells. Significant increase in relative luciferase activity was already evident after 2.5 µM benzo[a]pyrene, 5 µM formaldehyde, 0.006 µg/L bottom-EOM, 0.10 µg/L side-EOM or 0.06 µg/L top-EOM, where no cytotoxic damage was observed. Compared with the A549-luciferase cells, the tested pollutants produced higher induction of relative luciferase activity in HepG2-luciferase cells. Therefore, the new genotoxicity test systems can detect different types of genotoxic agents and low concentrations of environmental samples. The luciferase reporter cells, especially the HepG2-luciferase cells, could provide a valuable tool for rapid screening of the genotoxic damage of environmental pollutants and their complex mixtures.

Characterization of novel molecular photoacoustic contrast agents for in vivo photoacoustic tomography

NASA Astrophysics Data System (ADS)

Laoui, Samir

Photoacoustic tomography is a hybrid imaging modality that takes advantage of the high contrast of pure optical imaging and the high intrinsic resolution of ultrasound without the necessity of ionizing radiation. Photoacoustic imaging (PM) is neither purely optical nor purely acoustical in nature, but a combination of the two. It is fundamentally based on light excitation and ultrasonic detection. Photoacoustic imaging has been successful without the introduction of exogenous contrast agents; however, to image deeper regions of biological tissue, a contrast agent is necessary. Several types of photoacoustic contrast agents have been made available for diagnostic purposes; however, the majority of literature has focused on gold nanoparticle systems for which the surface-plasmon resonance effect is important. The only option currently available for molecular PM contrast agents is to choose an existing near infrared absorbing fluorescent probes with the hope that they may generate a substantial photoacoustic (PA) response. However, these dyes have been designed with an optimized fluorescence emission response and are not anticipated to generate an adequate photoacoustic response. This dissertation addresses this lack of precedence in the literature for understanding the mechanism of a photoacoustic signal generation from strongly absorbing dye molecules including BODIPY, cyanine and curcumin systems. This work represents preliminary efforts in bringing novel molecular photoacoustic contrast agents (MPACs) into the photoacoustic imaging arena. To this end, photoacoustic and optical Z-scan experiments, and quenching studies were employed to demonstrate correlation of photoacoustic emission enhancement with excited state absorption mechanisms. To investigate further the photoacoustic emission in a practical imaging setting, MPACs were imaged using a recently developed photoacoustic imaging tomography system which was constructed exclusively for the purpose of this study.

Mass spectrometry for the detection of bioterrorism agents: from environmental to clinical applications.

PubMed

Duriez, Elodie; Armengaud, Jean; Fenaille, François; Ezan, Eric

2016-03-01

In the current context of international conflicts and localized terrorist actions, there is unfortunately a permanent threat of attacks with unconventional warfare agents. Among these, biological agents such as toxins, microorganisms, and viruses deserve particular attention owing to their ease of production and dissemination. Mass spectrometry (MS)-based techniques for the detection and quantification of biological agents have a decisive role to play for countermeasures in a scenario of biological attacks. The application of MS to every field of both organic and macromolecular species has in recent years been revolutionized by the development of soft ionization techniques (MALDI and ESI), and by the continuous development of MS technologies (high resolution, accurate mass HR/AM instruments, novel analyzers, hybrid configurations). New possibilities have emerged for exquisite specific and sensitive detection of biological warfare agents. MS-based strategies for clinical application can now address a wide range of analytical questions mainly including issues related to the complexity of biological samples and their available volume. Multiplexed toxin detection, discovery of new markers through omics approaches, and identification of untargeted microbiological or of novel molecular targets are examples of applications. In this paper, we will present these technological advances along with the novel perspectives offered by omics approaches to clinical detection and follow-up. Copyright © 2016 John Wiley & Sons, Ltd.

Noninvasive detection and staging of oral cancer in vivo with confocal optoacoustic tomography

NASA Astrophysics Data System (ADS)

Savateeva, Elena V.; Karabutov, Alexander A.; Motamedi, Massoud; Bell, Brent A.; Johnigan, Richard M.; Oraevsky, Alexander A.

2000-05-01

Confocal opto-acoustic transducer (COAT) was developed and applied for detection of early stages of squamous cell carcinoma in hamster model of oral cancer. COAT is a novel imaging modality with optical and acoustic lens utilized for detecting in-depth opto-acoustic front surface transducer is an improved lateral resolution of 60-micrometers . The bandwidth of the confocal opto-acoustic transducer is more than 100 MHz. Therefore, in-depth axial resolution defined by the laser pulse duration and detection system equals 15-micrometers . Imaging was performed at the wavelength of the Nd:YAG laser second harmonic, which provided sufficient depth of monitoring and significant tissue contrast. Correlation of the opto- acoustic images with H and E histology sections in control animals and in animals treated with carcinogenic agent, DMBA, confirmed previous findings that early cancer lesions invisible by the naked eye may be detected with the opto- acoustic tomography. Compact design of COAT allows, in principle, application of the opto-acoustic imaging in any organ of the human digestive system.

Detection of Electrophilic and Nucleophilic Chemical Agents

DOEpatents

McElhanon, James R.; Shepodd, Timothy J.

2008-11-11

A "real time" method for detecting electrophilic and nucleophilic species generally by employing tunable, precursor sensor materials that mimic the physiological interaction of these agents to form highly florescent berberine-type alkaloids that can be easily and rapidly detected. These novel precursor sensor materials can be tuned for reaction with both electrophilic (chemical species, toxins) and nucleophilic (proteins and other biological molecules) species.

Instrument Would Detect and Collect Biological Aerosols

NASA Technical Reports Server (NTRS)

Savoy, Steve; Mayo, Mike

2006-01-01

A proposed compact, portable instrument would sample micron-sized airborne particles, would discriminate between biological ones (e.g., bacteria) and nonbiological ones (e.g., dust particles), and would collect the detected biological particles for further analysis. The instrument is intended to satisfy a growing need for means of rapid, inexpensive collection of bioaerosols in a variety of indoor and outdoor settings. Purposes that could be served by such collection include detecting airborne pathogens inside buildings and their ventilation systems, measuring concentrations of airborne biological contaminants around municipal waste-processing facilities, monitoring airborne effluents from suspected biowarfare facilities, and warning of the presence of airborne biowarfare agents

Structure Prediction of Protein Complexes

NASA Astrophysics Data System (ADS)

Pierce, Brian; Weng, Zhiping

Protein-protein interactions are critical for biological function. They directly and indirectly influence the biological systems of which they are a part. Antibodies bind with antigens to detect and stop viruses and other infectious agents. Cell signaling is performed in many cases through the interactions between proteins. Many diseases involve protein-protein interactions on some level, including cancer and prion diseases.

Lab-on-a-bubble: direct and indirect assays with portable Raman instrumentation

NASA Astrophysics Data System (ADS)

Carron, Keith; Schmit, Virginia; Scott, Brandon; Martoglio, Richard

2012-10-01

Lab-on-a-Bubble (LoB) is a new method for SERS (Surface Enhanced Raman Scattering) assays that combines separationand concentration of the assay results. A direct LoB assay is comprised of gold nanoparticles coupled directly to the ~30 μm diameter buoyant silica bubble. The direct LoB method was evaluated with cyanide and 5,5'-dithiobis(2-nitrobenzoic acid) (DTNB). An indirect assay uses the same ~ 30 μm diameter buoyant silica bubble and a silica coated SERS reporter. Both the bubble and SERS reporter are coated with a coupling agent for the analyte. The assay measures the amount of SERS reporter coupled to the bubble through a sandwich created by the analyte. The couling agent could consist of an immunological coupling agent (antibody) or a nucleic acid coupling agent (single strand DNA). The indirect LoB method was examined with Cholera toxin (CT) and antibodies against the β subunit. An LOD of ~ 170 pptrillion was measured for cyanide and a limit of detection of 1100 ng was found for CT. Instrumentation for the assay and a novel technique of dynamic SERS (DSERS) will also be discussed. The instrument is a small hand-held Raman device called the CBEx (Chemical Biological Explosive) with a novel raster system to detect heterogeneous or light sensitive materials. DSERS is a mathematical algorithm which eliminates background interference in SERS measurements with colloidal nanoparticles.

Detection of early changes in lung cell cytology by flow-systems analysis techniques. Progress report, January 1--December 31, 1978. [Resulting from exposure to toxic agents associated with production and use of synthetic fuels from oil shale and coal

DOE Office of Scientific and Technical Information (OSTI.GOV)

Steinkamp, J.A.; Wilson, J.S.; Svitra, Z.V.

1979-02-01

This report summarizes ongoing experiments to develop cytological and biochemical indicators for measuring damage to respiratory tract cells of experimental animals exposed by inhalation to environmental toxic agents. The specific goal is to apply flow cytometric methods to analyze and detect changes in lung epithelium as a function of exposure to toxic agents associated with the production and utilization of synthetic fuels from oil shale and coal. During the past 6 months, hamsters were exposed to raw and spent oil shale particulates, silica dust, and ozone, and DNA content measurements were performed on lung cell samples. Although initial shale exposuresmore » did not yield the expected results, recent data show atypical changes in DNA content per cell distributions. Ozone exposures also were expanded to include DNA measurements and cytology, ranging up to 72 h postexposure. Progress was achieved in developing a new method for quantitating pulmonary macrophage phagocytosis in rats using micron-sized fluorescent spheres. New methods for determining alkaline phosphatase, DNA content, and protein also were under development. Plans are to continue developing cytological and biochemical markers for measuring atypical cellular changes, including macrophage function, and to emphasize exposing experimental animals to particulates and gaseous agents for studying dose-damage relationships.« less

Differential mobility spectroscopy for chemical agent detection

NASA Astrophysics Data System (ADS)

Griffin, M. Todd

2006-05-01

General Dynamics ATP (GDATP) and Sionex Corporation (Sionex) are carrying out a cooperative development for a handheld chemical agent detector, being called JUNO TM, which will have lower false positives, higher sensitivity, and improved interference rejection compared with presently available detectors. This enhanced performance is made possible by the use of a new principle of ion separation called Differential Mobility Spectrometry (DMS). The enhanced selectivity is provided by the field tunable nature of the Sionex differential mobility technology (microDMxTM) which forms the analytical heart of the JUNO system and enables fingerprinting of molecules by characterization of the ionized molecular behavior under multiple electric field conditions. This enhanced selectivity is valuable in addressing not only the traditional list of chemical warfare agents (CWA) but also the substantial list of Toxic Industrial Compounds (TICs) and Toxic Industrial Materials (TIMs) which may be released in warfare or terrorist situations. Experimental results showing the ability of the microDMx to reject interferences, detect and resolve live agents are presented. An additional breakthrough in the technology was realized by operating the device at a reduced pressure of around 0.5 atmospheres. This reduced pressure operation resulted in roughly doubling the spectrometers resolution over what has previously been reported [1]. Advances have also been made in power consumption and packaging leading to a device suitable for portable, handheld, applications. Experimental results illustrating the performance of the microDMx technology employed in JUNO are highlighted.

Contrast-enhanced digital mammography (CEDM): imaging modeling, computer simulations, and phantom study

NASA Astrophysics Data System (ADS)

Chen, Biao; Jing, Zhenxue; Smith, Andrew

2005-04-01

Contrast enhanced digital mammography (CEDM), which is based upon the analysis of a series of x-ray projection images acquired before/after the administration of contrast agents, may provide physicians critical physiologic and morphologic information of breast lesions to determine the malignancy of lesions. This paper proposes to combine the kinetic analysis (KA) of contrast agent uptake/washout process and the dual-energy (DE) contrast enhancement together to formulate a hybrid contrast enhanced breast-imaging framework. The quantitative characteristics of materials and imaging components in the x-ray imaging chain, including x-ray tube (tungsten) spectrum, filter, breast tissues/lesions, contrast agents (non-ionized iodine solution), and selenium detector, were systematically modeled. The contrast-noise-ration (CNR) of iodinated lesions and mean absorbed glandular dose were estimated mathematically. The x-ray techniques optimization was conducted through a series of computer simulations to find the optimal tube voltage, filter thickness, and exposure levels for various breast thicknesses, breast density, and detectable contrast agent concentration levels in terms of detection efficiency (CNR2/dose). A phantom study was performed on a modified Selenia full field digital mammography system to verify the simulated results. The dose level was comparable to the dose in diagnostic mode (less than 4 mGy for an average 4.2 cm compressed breast). The results from the computer simulations and phantom study are being used to optimize an ongoing clinical study.

Nucleic acid in-situ hybridization detection of infectious agents

NASA Astrophysics Data System (ADS)

Thompson, Curtis T.

2000-04-01

Limitations of traditional culture methods and newer polymerase chain reaction (PCR)-based methods for detection and speciation of infectious agents demonstrate the need for more rapid and better diagnostics. Nucleic acid hybridization is a detection technology that has gained wide acceptance in cancer and prenatal cytogenetics. Using a modification of the nucleic acid hybridization technique known as fluorescence in-situ hybridization, infectious agents can be detected in a variety of specimens with high sensitivity and specificity. The specimens derive from all types of human and animal sources including body fluids, tissue aspirates and biopsy material. Nucleic acid hybridization can be performed in less than one hour. The result can be interpreted either using traditional fluorescence microscopy or automated platforms such as micro arrays. This paper demonstrates proof of concept for nucleic acid hybridization detection of different infectious agents. Interpretation within a cytologic and histologic context is possible with fluorescence microscopic analysis, thereby providing confirmatory evidence of hybridization. With careful probe selection, nucleic acid hybridization promises to be a highly sensitive and specific practical diagnostic alternative to culture, traditional staining methods, immunohistochemistry and complicated nucleic acid amplification tests.

A Software Framework for Remote Patient Monitoring by Using Multi-Agent Systems Support.

PubMed

Fernandes, Chrystinne Oliveira; Lucena, Carlos José Pereira De

2017-03-27

Although there have been significant advances in network, hardware, and software technologies, the health care environment has not taken advantage of these developments to solve many of its inherent problems. Research activities in these 3 areas make it possible to apply advanced technologies to address many of these issues such as real-time monitoring of a large number of patients, particularly where a timely response is critical. The objective of this research was to design and develop innovative technological solutions to offer a more proactive and reliable medical care environment. The short-term and primary goal was to construct IoT4Health, a flexible software framework to generate a range of Internet of things (IoT) applications, containing components such as multi-agent systems that are designed to perform Remote Patient Monitoring (RPM) activities autonomously. An investigation into its full potential to conduct such patient monitoring activities in a more proactive way is an expected future step. A framework methodology was selected to evaluate whether the RPM domain had the potential to generate customized applications that could achieve the stated goal of being responsive and flexible within the RPM domain. As a proof of concept of the software framework's flexibility, 3 applications were developed with different implementations for each framework hot spot to demonstrate potential. Agents4Health was selected to illustrate the instantiation process and IoT4Health's operation. To develop more concrete indicators of the responsiveness of the simulated care environment, an experiment was conducted while Agents4Health was operating, to measure the number of delays incurred in monitoring the tasks performed by agents. IoT4Health's construction can be highlighted as our contribution to the development of eHealth solutions. As a software framework, IoT4Health offers extensibility points for the generation of applications. Applications can extend the framework in the following ways: identification, collection, storage, recovery, visualization, monitoring, anomalies detection, resource notification, and dynamic reconfiguration. Based on other outcomes involving observation of the resulting applications, it was noted that its design contributed toward more proactive patient monitoring. Through these experimental systems, anomalies were detected in real time, with agents sending notifications instantly to the health providers. We conclude that the cost-benefit of the construction of a more generic and complex system instead of a custom-made software system demonstrated the worth of the approach, making it possible to generate applications in this domain in a more timely fashion. ©Chrystinne Oliveira Fernandes, Carlos José Pereira De Lucena. Originally published in JMIR Medical Informatics (http://medinform.jmir.org), 27.03.2017.

Viral vectors for gene modification of plants as chem/bio sensors.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Manginell, Monica; Harper, Jason C.; Arango, Dulce C.

2006-11-01

Chemical or biological sensors that are specific, sensitive, and robust allowing intelligence gathering for verification of nuclear non-proliferation treaty compliance and detouring production of weapons of mass destruction are sorely needed. Although much progress has been made in the area of biosensors, improvements in sensor lifetime, robustness, and device packaging are required before these devices become widely used. Current chemical and biological detection and identification techniques require less-than-covert sample collection followed by transport to a laboratory for analysis. In addition to being expensive and time consuming, results can often be inconclusive due to compromised sample integrity during collection and transport.more » We report here a demonstration of a plant based sensor technology which utilizes mature and seedling plants as chemical sensors. One can envision genetically modifying native plants at a site of interest that can report the presence of specific toxins or chemicals. In this one year project we used a developed inducible expression system to show the feasibility of plant sensors. The vector was designed as a safe, non-infectious vector which could be used to invade, replicate, and introduce foreign genes into mature host plants that then allow the plant to sense chem/bio agents. The genes introduced through the vector included a reporter gene that encodes for green fluorescent protein (GFP) and a gene that encodes for a mammalian receptor that recognizes a chemical agent. Specifically, GFP was induced by the presence of 17-{beta}-Estradiol (estrogen). Detection of fluorescence indicated the presence of the target chemical agent. Since the sensor is a plant, costly device packaging development or manufacturing of the sensor were not required. Additionally, the biological recognition and reporting elements are maintained in a living, natural environment and therefore do not suffer from lifetime disadvantages typical of most biosensing platforms. Detection of the chem/bio agent reporter (GFP) can be detected only at a specific wavelength.« less

Development of a gas-cylinder-free plasma desorption/ionization system for on-site detection of chemical warfare agents.

PubMed

Iwai, Takahiro; Kakegawa, Ken; Aida, Mari; Nagashima, Hisayuki; Nagoya, Tomoki; Kanamori-Kataoka, Mieko; Miyahara, Hidekazu; Seto, Yasuo; Okino, Akitoshi

2015-06-02

A gas-cylinder-free plasma desorption/ionization system was developed to realize a mobile on-site analytical device for detection of chemical warfare agents (CWAs). In this system, the plasma source was directly connected to the inlet of a mass spectrometer. The plasma can be generated with ambient air, which is drawn into the discharge region by negative pressure in the mass spectrometer. High-power density pulsed plasma of 100 kW could be generated by using a microhollow cathode and a laboratory-built high-intensity pulsed power supply (pulse width: 10-20 μs; repetition frequency: 50 Hz). CWAs were desorbed and protonated in the enclosed space adjacent to the plasma source. Protonated sample molecules were introduced to the mass spectrometer by airflow through the discharge region. To evaluate the analytical performance of this device, helium and air plasma were directly irradiated to CWAs in the gas-cylinder-free plasma desorption/ionization system and the protonated molecules were analyzed by using an ion-trap mass spectrometer. A blister agent (nitrogen mustard 3) and nerve gases [cyclohexylsarin (GF), tabun (GA), and O-ethyl S-2-N,N-diisopropylaminoethyl methylphosphonothiolate (VX)] in solution in n-hexane were applied to the Teflon rod and used as test samples, after solvent evaporation. As a result, protonated molecules of CWAs were successfully observed as the characteristic ion peaks at m/z 204, 181, 163, and 268, respectively. In air plasma, the limits of detection were estimated to be 22, 20, 4.8, and 1.0 pmol, respectively, which were lower than those obtained with helium plasma. To achieve quantitative analysis, calibration curves were made by using CWA stimulant dipinacolyl methylphosphonate as an internal standard; straight correlation lines (R(2) = 0.9998) of the peak intensity ratios (target per internal standard) were obtained. Remarkably, GA and GF gave protonated dimer ions, and the ratios of the protonated dimer ions to the protonated monomers increased with the amount of GA and GF applied.

VEGFR2-Targeted Ultrasound Imaging Agent Enhances the Detection of Ovarian Tumors at Early Stage in Laying Hens, a Preclinical Model of Spontaneous Ovarian Cancer.

PubMed

Barua, Animesh; Yellapa, Aparna; Bahr, Janice M; Machado, Sergio A; Bitterman, Pincas; Basu, Sanjib; Sharma, Sameer; Abramowicz, Jacques S

2015-07-01

Tumor-associated neoangiogenesis (TAN) is an early event in ovarian cancer (OVCA) development. Increased expression of vascular endothelial growth factor receptor 2 (VEGFR2) by TAN vessels presents a potential target for early detection by ultrasound imaging. The goal of this study was to examine the suitability of VEGFR2-targeted ultrasound contrast agents in detecting spontaneous OVCA in laying hens. Effects of VEGFR2-targeted contrast agents in enhancing the intensity of ultrasound imaging from spontaneous ovarian tumors in hens were examined in a cross-sectional study. Enhancement in the intensity of ultrasound imaging was determined before and after injection of VEGFR2-targeted contrast agents. All ultrasound images were digitally stored and analyzed off-line. Following scanning, ovarian tissues were collected and processed for histology and detection of VEGFR2-expressing microvessels. Enhancement in visualization of ovarian morphology was detected by gray-scale imaging following injection of VEGFR2-targeted contrast agents. Compared with pre-contrast, contrast imaging enhanced the intensities of ultrasound imaging significantly (p < 0.0001) irrespective of the pathological status of ovaries. In contrast to normal hens, the intensity of ultrasound imaging was significantly (p < 0.0001) higher in hens with early stage OVCA and increased further in hens with late stage OVCA. Higher intensities of ultrasound imaging in hens with OVCA were positively correlated with increased (p < 0.0001) frequencies of VEGFR2-expressing microvessels. The results of this study suggest that VEGFR2-targeted contrast agents enhance the visualization of spontaneous ovarian tumors in hens at early and late stages of OVCA. The laying hen may be a suitable model to test new imaging agents and develop targeted therapeutics. © The Author(s) 2014.

Trust Management Considerations For the Cooperative Infrastructure Defense Framework: Trust Relationships, Evidence, and Decisions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maiden, Wendy M.

Cooperative Infrastructure Defense (CID) is a hierarchical, agent-based, adaptive, cyber-security framework designed to collaboratively protect multiple enclaves or organizations participating in a complex infrastructure. CID employs a swarm of lightweight, mobile agents called Sensors designed to roam hosts throughout a security enclave to find indications of anomalies and report them to host-based Sentinels. The Sensors’ findings become pieces of a larger puzzle, which the Sentinel puts together to determine the problem and respond per policy as given by the enclave-level Sergeant agent. Horizontally across multiple enclaves and vertically within each enclave, authentication and access control technologies are necessary but insufficientmore » authorization mechanisms to ensure that CID agents continue to fulfill their roles in a trustworthy manner. Trust management fills the gap, providing mechanisms to detect malicious agents and offering more robust mechanisms for authorization. This paper identifies the trust relationships throughout the CID hierarchy, the types of trust evidence that could be gathered, and the actions that the CID system could take if an entity is determined to be untrustworthy.« less

A three-state kinetic agent-based model to analyze tax evasion dynamics

NASA Astrophysics Data System (ADS)

Crokidakis, Nuno

2014-11-01

In this work we study the problem of tax evasion on a fully-connected population. For this purpose, we consider that the agents may be in three different states, namely honest tax payers, tax evaders and undecided, that are individuals in an intermediate class among honests and evaders. Every individual can change his/her state following a kinetic exchange opinion dynamics, where the agents interact by pairs with competitive negative (with probability q) and positive (with probability 1-q) couplings, representing agreement/disagreement between pairs of agents. In addition, we consider the punishment rules of the Zaklan econophysics model, for which there is a probability pa of an audit each agent is subject to in every period and a length of time k detected tax evaders remain honest. Our results suggest that below the critical point qc=1/4 of the opinion dynamics the compliance is high, and the punishment rules have a small effect in the population. On the other hand, for q>qc the tax evasion can be considerably reduced by the enforcement mechanism. We also discuss the impact of the presence of the undecided agents in the evolution of the system.

Biological and chemical terrorism: strategic plan for preparedness and response. Recommendations of the CDC Strategic Planning Workgroup.

PubMed

2000-04-21

The U.S. national civilian vulnerability to the deliberate use of biological and chemical agents has been highlighted by recognition of substantial biological weapons development programs and arsenals in foreign countries, attempts to acquire or possess biological agents by militants, and high-profile terrorist attacks. Evaluation of this vulnerability has focused on the role public health will have detecting and managing the probable covert biological terrorist incident with the realization that the U.S. local, state, and federal infrastructure is already strained as a result of other important public health problems. In partnership with representatives for local and state health departments, other federal agencies, and medical and public health professional associations, CDC has developed a strategic plan to address the deliberate dissemination of biological or chemical agents. The plan contains recommendations to reduce U.S. vulnerability to biological and chemical terrorism--preparedness planning, detection and surveillance, laboratory analysis, emergency response, and communication systems. Training and research are integral components for achieving these recommendations. Success of the plan hinges on strengthening the relationships between medical and public health professionals and on building new partnerships with emergency management, the military, and law enforcement professionals.

Detection and isolation of nucleic acid sequences using a bifunctional hybridization probe

DOEpatents

Lucas, Joe N.; Straume, Tore; Bogen, Kenneth T.

2000-01-01

A method for detecting and isolating a target sequence in a sample of nucleic acids is provided using a bifunctional hybridization probe capable of hybridizing to the target sequence that includes a detectable marker and a first complexing agent capable of forming a binding pair with a second complexing agent. A kit is also provided for detecting a target sequence in a sample of nucleic acids using a bifunctional hybridization probe according to this method.

Role of phermones and kairmones for insect suppression systems and their possible health and environmental impacts.

PubMed Central

Knipling, E F

1976-01-01

Insects produce pheromones as a chemical communication system to facilitate reproduction. These highly active chemical attractants have been synthesized for some of the most important insect pests, including the boll weevil, gypsy moth, codling moth, tobacco budworm, European corn borer, and several bark beetles. While none of the synthetic sex attractants have yet been developed for use in insect control, they offer opportunities for the future both as control agents and to greatly improved insect detection. Investigations are underway on insect trapping systems employing the phermones and on air permeation techniques to disrupt insect reproduction. The pheromones are generally highly species-specific and are not likely to pose hazards to nontarget organisms in the environment. Toxicological studies indicate that they are low in toxicity to mammals, birds, and fish, but adequate toxicological data are necessary before they can be registered for use in insect control. Another new class of compounds called kaironomes has been discovered. These chemicals are involved in the detection of hosts or prey by insect parasites and predators. Kairomones may prove useful in manipulating natural or released biological agents for more effective biological control of insect pests. No information is yet available on the toxicology of these chemicals. PMID:789061

How new concepts become universal scientific approaches: insights from citation network analysis of agent-based complex systems science.

PubMed

Vincenot, Christian E

2018-03-14

Progress in understanding and managing complex systems comprised of decision-making agents, such as cells, organisms, ecosystems or societies, is-like many scientific endeavours-limited by disciplinary boundaries. These boundaries, however, are moving and can actively be made porous or even disappear. To study this process, I advanced an original bibliometric approach based on network analysis to track and understand the development of the model-based science of agent-based complex systems (ACS). I analysed research citations between the two communities devoted to ACS research, namely agent-based (ABM) and individual-based modelling (IBM). Both terms refer to the same approach, yet the former is preferred in engineering and social sciences, while the latter prevails in natural sciences. This situation provided a unique case study for grasping how a new concept evolves distinctly across scientific domains and how to foster convergence into a universal scientific approach. The present analysis based on novel hetero-citation metrics revealed the historical development of ABM and IBM, confirmed their past disjointedness, and detected their progressive merger. The separation between these synonymous disciplines had silently opposed the free flow of knowledge among ACS practitioners and thereby hindered the transfer of methodological advances and the emergence of general systems theories. A surprisingly small number of key publications sparked the ongoing fusion between ABM and IBM research. Beside reviews raising awareness of broad-spectrum issues, generic protocols for model formulation and boundary-transcending inference strategies were critical means of science integration. Accessible broad-spectrum software similarly contributed to this change. From the modelling viewpoint, the discovery of the unification of ABM and IBM demonstrates that a wide variety of systems substantiate the premise of ACS research that microscale behaviours of agents and system-level dynamics are inseparably bound. © 2018 The Author(s).

Characteristics of Gadolinium Oxide Nanoparticles Using Terahertz Spectroscopy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Dongkyu; Maeng, Inhee; Son, Joo-Hiuk

2009-04-19

The penetration property of the terahertz electromagnetic (THz) wave is relevant to its use. We used the THz wave spectroscopy system which easily penetrates some materials that do not contain water, e.g., plastic and ceramics. The system has been developed for several purposes, including measuring the properties of semiconductors and bio-materials, and detecting plastic bombs and ceramic knives at airports. It is also used for medical imaging systems, such as magnetic resonance imaging (MRI), at some research institutes. It can show not only the difference in amplitude, but also the difference of the phase of each point of sample. MRImore » technology usually uses contrast agents to enhance the quality of the image. Gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA), made with a heavy metal ion, is commonly used as a clinical MRI contrast agent. Gadolinium oxide (Gd{sub 2}O{sub 3}) nanoparticle is a new contrast agent. It serves to equip the core of each particle with antibodies or ligands. It can freely circulate in blood vessels without amassing in the liver or lungs. This study shows the characteristics of gadolinium oxide nanoparticles to further advance terahertz medical imaging.« less

Sample preparation and detection device for infectious agents

DOEpatents

Miles, Robin R.; Wang, Amy W.; Fuller, Christopher K.; Lemoff, Asuncion V.; Bettencourt, Kerry A.; Yu, June

2003-06-10

A sample preparation and analysis device which incorporates both immunoassays and PCR assays in one compact, field-portable microchip. The device provides new capabilities in fluid and particle control which allows the building of a fluidic chip with no moving parts, thus decreasing fabrication cost and increasing the robustness of the device. The device can operate in a true continuous (not batch) mode. The device incorporates magnetohydrodynamic (MHD) pumps to move the fluid through the system, acoustic mixing and fractionation, dielectropheretic (DEP) sample concentration and purification, and on-chip optical detection capabilities.

Effects of Wearing NBC (Nuclear, Biological and Chemical) Protective Clothing in the Heat on Detection of Visual Signals

DTIC Science & Technology

1985-02-01

agents, as well as nuclear weaponry. In the face of’ such threats, the United States Army has developed equinment and clothing systems designed to...AD_ REPORT NO. T7185 EFFECTS OF WEARING NBC PROTECTIVE CLOTHING IN THE HEAT ON DETECTION OF VISUAL SIGNALS U S ARMY RESEARCH INSTITUTE N OF...CATALOG NUMBER T7/•5 ( 4. TITLE (and Subtitle) 5. TYPE OF REPORT & PERIOD COVERED Effects of Wearing NBC Protective Clothing in the Technical Report Heat

pH imaging of mouse kidneys in vivo using a frequency-dependent paraCEST agent

PubMed Central

Wu, Yunkou; Zhang, Shanrong; Soesbe, Todd C.; Yu, Jing; Vinogradov, Elena; Lenkinski, Robert E.; Sherry, A. Dean

2015-01-01

Purpose This study explored the feasibility of using a pH responsive paraCEST agent to image the pH gradient in kidneys of healthy mice. Methods CEST signals were acquired on an Agilent 9.4 T small animal MRI system using a steady-state gradient echo pulse sequence after a bolus injection of agent. The magnetic field inhomogeneity across each kidney was corrected using the WASSR method and pH maps were calculated by measuring the frequency of water exchange signal arising from the agent. Results Dynamic CEST studies demonstrated that the agent was readily detectable in kidneys only between 4 to 12 min post-injection. The CEST images showed a higher signal intensity in the pelvis and calyx regions and lower signal intensity in the medulla and cortex regions. The pH maps reflected tissue pH values spanning from 6.0 to 7.5 in kidneys of healthy mice. Conclusion This study demonstrated that pH maps of the kidney can be imaged in vivo by measuring the pH-dependent chemical shift of a single water exchange CEST peak without prior knowledge of the agent concentration in vivo. The results demonstrate the potential of using a simple frequency-dependent paraCEST agent for mapping tissue pH in vivo. PMID:26173637

A Multi Agent System for Flow-Based Intrusion Detection Using Reputation and Evolutionary Computation

DTIC Science & Technology

2011-03-01

the actions of malicious and benign users of the Internet, as well as the engi- neering decisions giving rise to observed network topologies. Say and...with resilience, which is particularly important in the domain of quickly-evolving cyber threats. “Self-organization,” says Meadows, “is basically the...system design paradigm is to leverage the advantages of a distributed approach? What is meant by saying the witness conceptually rates the target

Evaluation of (1-Sarcosine, 8-Isoleucine) Angiotensin II as a Therapeutic Agent for OLEIC Acid-Induced Pulmonary Edema

DTIC Science & Technology

1986-02-01

during continuous intravenous infusion of the drug. No for angiotensinogenic hypertension . Clinical trials indi- changes were detected in systemic or...results suggest that (1-Sar, 8-Ile) A II may have of synthetic angiotensin 11 analogue. Jpn Circ J 38:997.1003, some desirable effects on the systemic ...Hata T, sive Kumahara Y: Changes of blood pressure, plasma renin activity pressure and peripheral resistance without changing and plasma aldosterone

Mechanistic insights into the luminescent sensing of organophosphorus chemical warfare agents and simulants using trivalent lanthanide complexes.

PubMed

Dennison, Genevieve H; Johnston, Martin R

2015-04-20

Organophosphorus chemical warfare agents (OP CWAs) are potent acetylcholinesterase inhibitors that can cause incapacitation and death within minutes of exposure, and furthermore are largely undetectable by the human senses. Fast, efficient, sensitive and selective detection of these compounds is therefore critical to minimise exposure. Traditional molecular-based sensing approaches have exploited the chemical reactivity of the OP CWAs, whereas more recently supramolecular-based approaches using non-covalent interactions have gained momentum. This is due, in part, to the potential development of sensors with second-generation properties, such as reversibility and multifunction capabilities. Supramolecular sensors also offer opportunities for incorporation of metal ions allowing for the exploitation of their unique properties. In particular, trivalent lanthanide ions are being increasingly used in the OP CWA sensing event and their use in supramolecular sensors is discussed in this Minireview. We focus on the fundamental interactions of simple lanthanide systems with OP CWAs and simulants, along with the development of more elaborate and complex systems including those containing nanotubes, polymers and gold nanoparticles. Whilst literature investigations into lanthanide-based OP CWA detection systems are relatively scarce, their unique and versatile properties provide a promising platform for the development of more efficient and complex sensing systems into the future. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Occurrence and fate of organic contaminants during onsite wastewater treatment

USGS Publications Warehouse

Conn, K.E.; Barber, L.B.; Brown, G.K.; Siegrist, R.L.

2006-01-01

Onsite wastewater treatment systems serve approximately 25% of the U.S. population. However, little is known regarding the occurrence and fate of organic wastewater contaminants (OWCs), including endocrine disrupting compounds, during onsite treatment. A range of OWCs including surfactant metabolites, steroids, stimulants, metal-chelating agents, disinfectants, antimicrobial agents, and pharmaceutical compounds was quantified in wastewater from 30 onsite treatment systems in Summit and Jefferson Counties, CO. The onsite systems represent a range of residential and nonresidential sources. Eighty eight percent of the 24 target compounds were detected in one or more samples, and several compounds were detected in every wastewater sampled. The wastewater matrices were complex and showed unique differences between source types due to differences in water and consumer product use. Nonresidential sources generally had more OWCs at higher concentrations than residential sources. Additional aerobic biofilter-based treatment beyond the traditional anaerobic tank-based treatment enhanced removal for many OWCs. Removal mechanisms included volatilization, biotransformation, and sorption with efficiencies from 99% depending on treatment type and physicochemical properties of the compound. Even with high removal rates during confined unit onsite treatment, OWCs are discharged to soil dispersal units at loadings up to 20 mg/m2/d, emphasizing the importance of understanding removal mechanisms and efficiencies in onsite treatment systems that discharge to the soil and water environments. ?? 2006 American Chemical Society.

A game theoretic algorithm to detect overlapping community structure in networks

NASA Astrophysics Data System (ADS)

Zhou, Xu; Zhao, Xiaohui; Liu, Yanheng; Sun, Geng

2018-04-01

Community detection can be used as an important technique for product and personalized service recommendation. A game theory based approach to detect overlapping community structure is introduced in this paper. The process of the community formation is converted into a game, when all agents (nodes) cannot improve their own utility, the game process will be terminated. The utility function is composed of a gain and a loss function and we present a new gain function in this paper. In addition, different from choosing action randomly among join, quit and switch for each agent to get new label, two new strategies for each agent to update its label are designed during the game, and the strategies are also evaluated and compared for each agent in order to find its best result. The overlapping community structure is naturally presented when the stop criterion is satisfied. The experimental results demonstrate that the proposed algorithm outperforms other similar algorithms for detecting overlapping communities in networks.

[The development and implementation of polymerase chain reaction to detect in real-time operation mode yersinia pestis in field material].

PubMed

Afanas'ev, M V; Chipanin, E V; Shestakov, V E; Denisov, A V; Fomina, L A; Ostiak, A S; Balakhonov, S V

2013-03-01

The article presents the results of development and practical implementation of system of polymerase chain reaction testing in real-time operation mode to detect agent of plague infield material. In laboratory conditions the system demonstrated good results and hence it was applied in conditions of field laboratory of epidemiologic team during planned epizootologic examination of Gorno-Altaisk hot spot of plague. The sampling consisted of more than 1400 objects. It was demonstrated that high sensitivity and specificity is immanent to proposed system. The adaptation of the system to the real time amplifier "Smart Cycler" (Cephid, USA) having some specific technical characteristics makes it possible to consider the proposed test-system as an effective sensitive and precise instrument for screening studies in the process of regular epizootologic examinations of hot spots of plague.

Just one look: Direct gaze briefly disrupts visual working memory.

PubMed

Wang, J Jessica; Apperly, Ian A

2017-04-01

Direct gaze is a salient social cue that affords rapid detection. A body of research suggests that direct gaze enhances performance on memory tasks (e.g., Hood, Macrae, Cole-Davies, & Dias, Developmental Science, 1, 67-71, 2003). Nonetheless, other studies highlight the disruptive effect direct gaze has on concurrent cognitive processes (e.g., Conty, Gimmig, Belletier, George, & Huguet, Cognition, 115(1), 133-139, 2010). This discrepancy raises questions about the effects direct gaze may have on concurrent memory tasks. We addressed this topic by employing a change detection paradigm, where participants retained information about the color of small sets of agents. Experiment 1 revealed that, despite the irrelevance of the agents' eye gaze to the memory task at hand, participants were worse at detecting changes when the agents looked directly at them compared to when the agents looked away. Experiment 2 showed that the disruptive effect was relatively short-lived. Prolonged presentation of direct gaze led to recovery from the initial disruption, rather than a sustained disruption on change detection performance. The present study provides the first evidence that direct gaze impairs visual working memory with a rapidly-developing yet short-lived effect even when there is no need to attend to agents' gaze.

Response of detoxification system genes on Chironomus riparius aquatic larvae after antibacterial agent triclosan exposures.

PubMed

Martínez-Paz, Pedro

2018-05-15

Triclosan (TCS) is an antimicrobial agent used in a range of personal care and consumer products and is commonly detected in aquatic ecosystems. In the present study, the effects of TCS at the molecular level on the detoxification system of Chironomus riparius aquatic larvae, a test organism widely used for the assessment of aquatic toxicology, were evaluated. The obtained results show that this xenobiotic was able to induce significant changes in transcripts from different cytochrome P450s and glutathione s-transferases genes, involved in phase I and phase II of detoxification system, respectively. In contrast, TCS did not affect the glutathione S-transferase enzyme activity nor the expression pattern of multidrug resistance-associated protein 1, which belongs to phase III of detoxification system. These results provide information about the effects of TCS on the detoxification mechanism of C. riparius and offers different biomarker genes that could be useful in ecotoxicological studies, risk assessment and bioremediation. Copyright © 2017 Elsevier B.V. All rights reserved.

Application of zonal model on indoor air sensor network design

NASA Astrophysics Data System (ADS)

Chen, Y. Lisa; Wen, Jin

2007-04-01

Growing concerns over the safety of the indoor environment have made the use of sensors ubiquitous. Sensors that detect chemical and biological warfare agents can offer early warning of dangerous contaminants. However, current sensor system design is more informed by intuition and experience rather by systematic design. To develop a sensor system design methodology, a proper indoor airflow modeling approach is needed. Various indoor airflow modeling techniques, from complicated computational fluid dynamics approaches to simplified multi-zone approaches, exist in the literature. In this study, the effects of two airflow modeling techniques, multi-zone modeling technique and zonal modeling technique, on indoor air protection sensor system design are discussed. Common building attack scenarios, using a typical CBW agent, are simulated. Both multi-zone and zonal models are used to predict airflows and contaminant dispersion. Genetic Algorithm is then applied to optimize the sensor location and quantity. Differences in the sensor system design resulting from the two airflow models are discussed for a typical office environment and a large hall environment.

Triage, monitoring, and treatment of mass casualty events involving chemical, biological, radiological, or nuclear agents

PubMed Central

Ramesh, Aruna C.; Kumar, S.

2010-01-01

In a mass casualty situation due to chemical, biological, radiological, or nuclear (CBRN) event, triage is absolutely required for categorizing the casualties in accordance with medical care priorities. Dealing with a CBRN event always starts at the local level. Even before the detection and analysis of agents can be undertaken, zoning, triage, decontamination, and treatment should be initiated promptly. While applying the triage system, the available medical resources and maximal utilization of medical assets should be taken into consideration by experienced triage officers who are most familiar with the natural course of the injury presented and have detailed information on medical assets. There are several triage systems that can be applied to CBRN casualties. With no one standardized system globally or nationally available, it is important for deploying a triage and decontamination system which is easy to follow and flexible to the available medical resources, casualty number, and severity of injury. PMID:21829319

Development and Evaluation of Sensor Concepts for Ageless Aerospace Vehicles: Report 5 - Phase 2 Implementation of the Concept Demonstrator

NASA Technical Reports Server (NTRS)

Batten, Adam; Dunlop, John; Edwards, Graeme; Farmer, Tony; Gaffney, Bruce; Hedley, Mark; Hoschke, Nigel; Isaacs, Peter; Johnson, Mark; Lewis, Chris;

Advances in Molecular Imaging of Locally Delivered Targeted Therapeutics for Central Nervous System Tumors

PubMed Central

Tosi, Umberto; Marnell, Christopher S.; Chang, Raymond; Cho, William C.; Ting, Richard; Maachani, Uday B.; Souweidane, Mark M.

2017-01-01

Thanks to the recent advances in the development of chemotherapeutics, the morbidity and mortality of many cancers has decreased significantly. However, compared to oncology in general, the field of neuro-oncology has lagged behind. While new molecularly targeted chemotherapeutics have emerged, the impermeability of the blood–brain barrier (BBB) renders systemic delivery of these clinical agents suboptimal. To circumvent the BBB, novel routes of administration are being applied in the clinic, ranging from intra-arterial infusion and direct infusion into the target tissue (convection enhanced delivery (CED)) to the use of focused ultrasound to temporarily disrupt the BBB. However, the current system depends on a “wait-and-see” approach, whereby drug delivery is deemed successful only when a specific clinical outcome is observed. The shortcomings of this approach are evident, as a failed delivery that needs immediate refinement cannot be observed and corrected. In response to this problem, new theranostic agents, compounds with both imaging and therapeutic potential, are being developed, paving the way for improved and monitored delivery to central nervous system (CNS) malignancies. In this review, we focus on the advances and the challenges to improve early cancer detection, selection of targeted therapy, and evaluation of therapeutic efficacy, brought forth by the development of these new agents. PMID:28208698

Advances in Molecular Imaging of Locally Delivered Targeted Therapeutics for Central Nervous System Tumors.

PubMed

Tosi, Umberto; Marnell, Christopher S; Chang, Raymond; Cho, William C; Ting, Richard; Maachani, Uday B; Souweidane, Mark M

2017-02-08

Thanks to the recent advances in the development of chemotherapeutics, the morbidity and mortality of many cancers has decreased significantly. However, compared to oncology in general, the field of neuro-oncology has lagged behind. While new molecularly targeted chemotherapeutics have emerged, the impermeability of the blood-brain barrier (BBB) renders systemic delivery of these clinical agents suboptimal. To circumvent the BBB, novel routes of administration are being applied in the clinic, ranging from intra-arterial infusion and direct infusion into the target tissue (convection enhanced delivery (CED)) to the use of focused ultrasound to temporarily disrupt the BBB. However, the current system depends on a "wait-and-see" approach, whereby drug delivery is deemed successful only when a specific clinical outcome is observed. The shortcomings of this approach are evident, as a failed delivery that needs immediate refinement cannot be observed and corrected. In response to this problem, new theranostic agents, compounds with both imaging and therapeutic potential, are being developed, paving the way for improved and monitored delivery to central nervous system (CNS) malignancies. In this review, we focus on the advances and the challenges to improve early cancer detection, selection of targeted therapy, and evaluation of therapeutic efficacy, brought forth by the development of these new agents.

Fluorine (19F) MRS and MRI in biomedicine

PubMed Central

Ruiz-Cabello, Jesús; Barnett, Brad P.; Bottomley, Paul A.; Bulte, Jeff W.M.

2011-01-01

Shortly after the introduction of 1H MRI, fluorinated molecules were tested as MR-detectable tracers or contrast agents. Many fluorinated compounds, which are nontoxic and chemically inert, are now being used in a broad range of biomedical applications, including anesthetics, chemotherapeutic agents, and molecules with high oxygen solubility for respiration and blood substitution. These compounds can be monitored by fluorine (19F) MRI and/or MRS, providing a noninvasive means to interrogate associated functions in biological systems. As a result of the lack of endogenous fluorine in living organisms, 19F MRI of ‘hotspots’ of targeted fluorinated contrast agents has recently opened up new research avenues in molecular and cellular imaging. This includes the specific targeting and imaging of cellular surface epitopes, as well as MRI cell tracking of endogenous macrophages, injected immune cells and stem cell transplants. PMID:20842758

Combination of Multi-Agent Systems and Wireless Sensor Networks for the Monitoring of Cattle

PubMed Central

Barriuso, Alberto L.; De Paz, Juan F.; Lozano, Álvaro

2018-01-01

Precision breeding techniques have been widely used to optimize expenses and increase livestock yields. Notwithstanding, the joint use of heterogeneous sensors and artificial intelligence techniques for the simultaneous analysis or detection of different problems that cattle may present has not been addressed. This study arises from the necessity to obtain a technological tool that faces this state of the art limitation. As novelty, this work presents a multi-agent architecture based on virtual organizations which allows to deploy a new embedded agent model in computationally limited autonomous sensors, making use of the Platform for Automatic coNstruction of orGanizations of intElligent Agents (PANGEA). To validate the proposed platform, different studies have been performed, where parameters specific to each animal are studied, such as physical activity, temperature, estrus cycle state and the moment in which the animal goes into labor. In addition, a set of applications that allow farmers to remotely monitor the livestock have been developed. PMID:29301310

Sonosensitive MRI nanosystems as Cancer Theranostics: a recent update

NASA Astrophysics Data System (ADS)

Garello, Francesca; Terreno, Enzo

2018-05-01

In the tireless search for innovative and more efficient cancer therapies, sonosensitive Magnetic Resonance Imaging (MRI) agents play an important role. Basically, these systems consist of nano/microvesicles composed by a biocompatible membrane, responsive to ultrasound-induced thermal or mechanical effects, and an aqueous core, filled up with a MRI detectable probe and a therapeutic agent. They offer the possibility to trigger and monitor in real time drug release in a spatio-temporal domain, with the expectation to predict the therapeutic outcome. In this review, the key items to design sonosensitive MRI agents will be examined and an overview on the different approaches available so far will be given. Due to the extremely wide range of adopted ultrasound settings and formulations conceived, it is hard to compare the numerous preclinical studies reported. However, in general, a significantly better therapeutic outcome was noticed when exploiting ultrasound triggered drug release in comparison to traditional therapies, thus paving the way to the possible clinical translation of optimized sonosensitive MRI agents.

Combination of Multi-Agent Systems and Wireless Sensor Networks for the Monitoring of Cattle.

PubMed

Barriuso, Alberto L; Villarrubia González, Gabriel; De Paz, Juan F; Lozano, Álvaro; Bajo, Javier

2018-01-02

Precision breeding techniques have been widely used to optimize expenses and increase livestock yields. Notwithstanding, the joint use of heterogeneous sensors and artificial intelligence techniques for the simultaneous analysis or detection of different problems that cattle may present has not been addressed. This study arises from the necessity to obtain a technological tool that faces this state of the art limitation. As novelty, this work presents a multi-agent architecture based on virtual organizations which allows to deploy a new embedded agent model in computationally limited autonomous sensors, making use of the Platform for Automatic coNstruction of orGanizations of intElligent Agents (PANGEA). To validate the proposed platform, different studies have been performed, where parameters specific to each animal are studied, such as physical activity, temperature, estrus cycle state and the moment in which the animal goes into labor. In addition, a set of applications that allow farmers to remotely monitor the livestock have been developed.

A cognitive robotic system based on the Soar cognitive architecture for mobile robot navigation, search, and mapping missions

NASA Astrophysics Data System (ADS)

Hanford, Scott D.

Most unmanned vehicles used for civilian and military applications are remotely operated or are designed for specific applications. As these vehicles are used to perform more difficult missions or a larger number of missions in remote environments, there will be a great need for these vehicles to behave intelligently and autonomously. Cognitive architectures, computer programs that define mechanisms that are important for modeling and generating domain-independent intelligent behavior, have the potential for generating intelligent and autonomous behavior in unmanned vehicles. The research described in this presentation explored the use of the Soar cognitive architecture for cognitive robotics. The Cognitive Robotic System (CRS) has been developed to integrate software systems for motor control and sensor processing with Soar for unmanned vehicle control. The CRS has been tested using two mobile robot missions: outdoor navigation and search in an indoor environment. The use of the CRS for the outdoor navigation mission demonstrated that a Soar agent could autonomously navigate to a specified location while avoiding obstacles, including cul-de-sacs, with only a minimal amount of knowledge about the environment. While most systems use information from maps or long-range perceptual capabilities to avoid cul-de-sacs, a Soar agent in the CRS was able to recognize when a simple approach to avoiding obstacles was unsuccessful and switch to a different strategy for avoiding complex obstacles. During the indoor search mission, the CRS autonomously and intelligently searches a building for an object of interest and common intersection types. While searching the building, the Soar agent builds a topological map of the environment using information about the intersections the CRS detects. The agent uses this topological model (along with Soar's reasoning, planning, and learning mechanisms) to make intelligent decisions about how to effectively search the building. Once the object of interest has been detected, the Soar agent uses the topological map to make decisions about how to efficiently return to the location where the mission began. Additionally, the CRS can send an email containing step-by-step directions using the intersections in the environment as landmarks that describe a direct path from the mission's start location to the object of interest. The CRS has displayed several characteristics of intelligent behavior, including reasoning, planning, learning, and communication of learned knowledge, while autonomously performing two missions. The CRS has also demonstrated how Soar can be integrated with common robotic motor and perceptual systems that complement the strengths of Soar for unmanned vehicles and is one of the few systems that use perceptual systems such as occupancy grid, computer vision, and fuzzy logic algorithms with cognitive architectures for robotics. The use of these perceptual systems to generate symbolic information about the environment during the indoor search mission allowed the CRS to use Soar's planning and learning mechanisms, which have rarely been used by agents to control mobile robots in real environments. Additionally, the system developed for the indoor search mission represents the first known use of a topological map with a cognitive architecture on a mobile robot. The ability to learn both a topological map and production rules allowed the Soar agent used during the indoor search mission to make intelligent decisions and behave more efficiently as it learned about its environment. While the CRS has been applied to two different missions, it has been developed with the intention that it be extended in the future so it can be used as a general system for mobile robot control. The CRS can be expanded through the addition of new sensors and sensor processing algorithms, development of Soar agents with more production rules, and the use of new architectural mechanisms in Soar.

Studies of MRI relaxivities of gadolinium-labeled dendrons

NASA Astrophysics Data System (ADS)

Pan, Hongmu; Daniel, Marie-Christine

2011-05-01

In cancer detection, imaging techniques have a great importance in early diagnosis. The more sensitive the imaging technique and the earlier the tumor can be detected. Contrast agents have the capability to increase the sensitivity in imaging techniques such as magnetic resonance imaging (MRI). Until now, gadolinium-based contrast agents are mainly used for MRI, and show good enhancement. But improvement is needed for detection of smaller tumors at the earliest stage possible. The dendrons complexed with Gd(DOTA) were synthesized and evaluated as a new MRI contrast agent. The longitudinal and transverse relaxation effects were tested and compared with commercial drug Magnevist, Gd(DTPA).

Identification of chemical warfare agents from vapor samples using a field-portable capillary gas chromatography/membrane-interfaced electron ionization quadrupole mass spectrometry instrument with Tri-Bed concentrator.

PubMed

Nagashima, Hisayuki; Kondo, Tomohide; Nagoya, Tomoki; Ikeda, Toru; Kurimata, Naoko; Unoke, Shohei; Seto, Yasuo

2015-08-07

A field-portable gas chromatograph-mass spectrometer (Hapsite ER system) was evaluated for the detection of chemical warfare agents (CWAs) in the vapor phase. The system consisted of Tri-Bed concentrator gas sampler (trapping time: 3s(-1)min), a nonpolar low thermal-mass capillary gas chromatography column capable of raising temperatures up to 200°C, a hydrophobic membrane-interfaced electron ionization quadrupole mass spectrometer evacuated by a non-evaporative getter pump for data acquisition, and a personal computer for data analysis. Sample vapors containing as little as 22μg sarin (GB), 100μg soman (GD), 210μg tabun (GA), 55μg cyclohexylsarin (GF), 4.8μg sulfur mustard, 390μg nitrogen mustard 1, 140μg of nitrogen mustard 2, 130μg nitrogen mustard 3, 120μg of 2-chloroacetophenone and 990μg of chloropicrin per cubic meter could be confirmed after Tri-Bed micro-concentration (for 1min) and automated AMDIS search within 12min. Using manual deconvolution by background subtraction of neighboring regions on the extracted ion chromatograms, the above-mentioned CWAs could be confirmed at lower concentration levels. The memory effects were also examined and we found that blister agents showed significantly more carry-over than nerve agents. Gasoline vapor was found to interfere with the detection of GB and GD, raising the concentration limits for confirmation in the presence of gasoline by both AMDIS search and manual deconvolution; however, GA and GF were not subject to interference by gasoline. Lewisite 1, and o-chlorobenzylidene malononitrile could also be confirmed by gas chromatography, but it was hard to quantify them. Vapors of phosgene, chlorine, and cyanogen chloride could be confirmed by direct mass spectrometric detection at concentration levels higher than 2, 140, and 10mg/m(3) respectively, by bypassing the micro-concentration trap and gas chromatographic separation. Copyright © 2015 Elsevier B.V. All rights reserved.

MicroChemLab, A Novel Approach for Handheld Chemical Sensing

NASA Astrophysics Data System (ADS)

Lewis, Patrick

2003-03-01

In 1996, Sandia National Laboratories began development of a chemical sensing platform based on microfabricated components. The goal of the project was to develop a handheld system for the detection of chemical warfare (CW) agent vapors in air. The components developed for this project are analogous to devices used in analytical laboratories. The benefit of microfabrication is that the resulting components are small and require little power to operate. The key elements of MicroChemLab are a sample collector - preconcentrator, a GC column and a surface acoustic wave (SAW) array detector. The preconcentrator is a thermally isolated silicon nitride membrane with a resistive heater patterned on one side and a sorptive sol gel film deposited on the other. Since the membrane has a very small mass, the resistive heater can ballistically elevate the temperature of the sorptive film to 200° C in approximately 10 ms. The sol gel film collects target compounds efficiently, but rejects volatile industrial solvents like alcohols, ketones, etc. The GC column is a one-meter high aspect ratio spiral channel etched in silicon with an anodically bonded pyrex lid completing the channel. A heater patterned on the silicon allows the column to be temperature ramped. Analytes injected from the preconcentrator are separated in this stage. The SAW array detector contains 3 delay lines used for sensing and 1 reference delay line. Each delay line is driven by an application specific integrated circuit (ASIC) at 500 MHz. Instead of counting frequency, additional ASICs incorporate a phase comparator that delivers a DC signal proportional to the amount of phase change. The three sensing elements of the detector provide a pattern that is indicative of the class of compound detected i.e. nerve agents or blister agents. Combined, these components provide a selective and sensitive handheld solution for the detection of chemical warfare agents. We will present lab data showing the performance of individual components and field data demonstrating the performance of this system. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy under Contract DE-AC04-94AL85000.

Nanodiamond-Manganese dual mode MRI contrast agents for enhanced liver tumor detection.

PubMed

Hou, Weixin; Toh, Tan Boon; Abdullah, Lissa Nurrul; Yvonne, Tay Wei Zheng; Lee, Kuan J; Guenther, Ilonka; Chow, Edward Kai-Hua

2017-04-01

Contrast agent-enhanced magnetic resonance (MR) imaging is critical for the diagnosis and monitoring of a number of diseases, including cancer. Certain clinical applications, including the detection of liver tumors, rely on both T1 and T2-weighted images even though contrast agent-enhanced MR imaging is not always reliable. Thus, there is a need for improved dual mode contrast agents with enhanced sensitivity. We report the development of a nanodiamond-manganese dual mode contrast agent that enhanced both T1 and T2-weighted MR imaging. Conjugation of manganese to nanodiamonds resulted in improved longitudinal and transverse relaxivity efficacy over unmodified MnCl 2 as well as clinical contrast agents. Following intravenous administration, nanodiamond-manganese complexes outperformed current clinical contrast agents in an orthotopic liver cancer mouse model while also reducing blood serum concentration of toxic free Mn 2+ ions. Thus, nanodiamond-manganese complexes may serve as more effective dual mode MRI contrast agent, particularly in cancer. Copyright © 2016 Elsevier Inc. All rights reserved.

Military Role in Countering Terrorist Use of Weapons of Mass Destruction

DTIC Science & Technology

1999-04-01

chemical and biological mobile point detection. “The M21 Remote Sensing Chemical Agent Alarm (RSCAAL) is an automatic scanning, passive infrared sensor...The M21 detects nerve and blister agent clouds based on changes in the background infrared spectra caused by the presence of the agent vapor.”15...required if greater than 3 years since last vaccine. VEE Yes Multiple vaccines required. VHF No Botulism Yes SEB No Ricin No Mycotoxin s No Source

Biocompatible, Biodegradable, and Enzymatic-Cleavable MRI Contrast Agents for Early Detection of Bone Metastatic Breast Cancer

DTIC Science & Technology

2012-04-01

detection of bone metastasis from breast cancer. The proposed imaging agent is consist of bone targeting moiety of Asp8 and MRI imaging moiety of DOTA ...peptide onto DOTA followed by Gd complexation was performed to achieve the proposed imaging agent. Non-targeting and CTSK-insensitive controls were...synthesis (SPPS) strategy, and purified by preparative HPLC. The chemical structures of peptides were shown below. Peptides reacted with DOTA -NHS

Ultrasound detection and identification of cosmetic fillers in the skin.

PubMed

Wortsman, X; Wortsman, J; Orlandi, C; Cardenas, G; Sazunic, I; Jemec, G B E

2012-03-01

While the incidence of cosmetic filler injections is rising world-wide, neither exact details of the procedure nor the agent used are always reported or remembered by the patients. Thus, although complications are reportedly rare, availability of a precise diagnostic tool to detect cutaneous filler deposits could help clarify the association between the procedure and the underlying pathology. The aim of this study was to evaluate cutaneous sonography in the detection and identification of cosmetic fillers deposits and, describe dermatological abnormalities found associated with the presence of those agents. We used ultrasound in a porcine skin model to determine the sonographic characteristics of commonly available filler agents, and subsequently applied the analysis to detect and identify cosmetic fillers among patients referred for skin disorders. Fillers are recognizable on ultrasound and generate different patterns of echogenicity and posterior acoustic artefacts. Cosmetic fillers were identified in 118 dermatological patients; most commonly hyaluronic acid among degradable agents and silicone oil among non-degradable. Fillers deposits were loosely scattered throughout the subcutaneous tissue, with occasional infiltration of local muscles and loco-regional lymph nodes. Accompanying dermatopathies were represented by highly localized inflammatory processes unresponsive to conventional treatment, morphea-like reactions, necrosis of fatty tissue and epidermal cysts; in the case of non-degradable agents, the associated dermatopathies were transient, resolving upon disappearance of the filler. Cosmetic filler agents may be detected and identified during routine ultrasound of dermatological lesions; the latter appear to be pathologically related to the cosmetic procedure. © 2011 The Authors. Journal of the European Academy of Dermatology and Venereology © 2011 European Academy of Dermatology and Venereology.

Visual discrimination of dihydroxybenzene isomers based on a nitrogen-doped graphene quantum dot-silver nanoparticle hybrid

NASA Astrophysics Data System (ADS)

Shi, Bingfang; Su, Yubin; Zhao, Jingjin; Liu, Rongjun; Zhao, Yan; Zhao, Shulin

2015-10-01

A room temperature reducing agent-free strategy for the synthesis of a nitrogen-doped graphene quantum dot-silver nanoparticle (N-GQD/AgNP) hybrid was presented. In this strategy, N-GQDs were used as a reducing agent and stabilizer for the formation of the N-GQD/AgNP hybrid, and the formation of the N-GQD/AgNP hybrid may result from the extraordinary reduction properties of N-GQDs, which are attributed to the nature of the surface oxygen-containing functional groups. The N-GQD/AgNP hybrid exhibits good dispersity and outstanding catalytic ability toward the oxidation of catechol (CC) and hydroquinone (HQ) by Ag+. In the presence of the N-GQD/AgNP hybrid, the reduction of Ag+ by CC and HQ was improved. CC enhanced the absorbance of the N-GQD/AgNP-Ag+ system the most, and HQ followed, while resorcinol (RC) had only a little effect on the absorption intensity of the system. Thus, a sensitive and selective colorimetric sensing method based on the N-GQD/AgNP-Ag+ system was developed for the discrimination of CC, HQ and RC. A good linear relationship was obtained from 0.1 to 15.0 μM for CC and from 0.3 to 20.0 μM for HQ. The detection limits of CC and HQ were 0.03 and 0.1 μM, respectively. In addition, the proposed method also shows a high selectivity for the detection of CC and HQ, and appreciable changes in color of the N-GQD/AgNP-Ag+ system toward CC, RC and HQ were observed.A room temperature reducing agent-free strategy for the synthesis of a nitrogen-doped graphene quantum dot-silver nanoparticle (N-GQD/AgNP) hybrid was presented. In this strategy, N-GQDs were used as a reducing agent and stabilizer for the formation of the N-GQD/AgNP hybrid, and the formation of the N-GQD/AgNP hybrid may result from the extraordinary reduction properties of N-GQDs, which are attributed to the nature of the surface oxygen-containing functional groups. The N-GQD/AgNP hybrid exhibits good dispersity and outstanding catalytic ability toward the oxidation of catechol (CC) and hydroquinone (HQ) by Ag+. In the presence of the N-GQD/AgNP hybrid, the reduction of Ag+ by CC and HQ was improved. CC enhanced the absorbance of the N-GQD/AgNP-Ag+ system the most, and HQ followed, while resorcinol (RC) had only a little effect on the absorption intensity of the system. Thus, a sensitive and selective colorimetric sensing method based on the N-GQD/AgNP-Ag+ system was developed for the discrimination of CC, HQ and RC. A good linear relationship was obtained from 0.1 to 15.0 μM for CC and from 0.3 to 20.0 μM for HQ. The detection limits of CC and HQ were 0.03 and 0.1 μM, respectively. In addition, the proposed method also shows a high selectivity for the detection of CC and HQ, and appreciable changes in color of the N-GQD/AgNP-Ag+ system toward CC, RC and HQ were observed. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr04659a

Development of stereotactic mass spectrometry for brain tumor surgery.

PubMed

Agar, Nathalie Y R; Golby, Alexandra J; Ligon, Keith L; Norton, Isaiah; Mohan, Vandana; Wiseman, Justin M; Tannenbaum, Allen; Jolesz, Ferenc A

2011-02-01

Surgery remains the first and most important treatment modality for the majority of solid tumors. Across a range of brain tumor types and grades, postoperative residual tumor has a great impact on prognosis. The principal challenge and objective of neurosurgical intervention is therefore to maximize tumor resection while minimizing the potential for neurological deficit by preserving critical tissue. To introduce the integration of desorption electrospray ionization mass spectrometry into surgery for in vivo molecular tissue characterization and intraoperative definition of tumor boundaries without systemic injection of contrast agents. Using a frameless stereotactic sampling approach and by integrating a 3-dimensional navigation system with an ultrasonic surgical probe, we obtained image-registered surgical specimens. The samples were analyzed with ambient desorption/ionization mass spectrometry and validated against standard histopathology. This new approach will enable neurosurgeons to detect tumor infiltration of the normal brain intraoperatively with mass spectrometry and to obtain spatially resolved molecular tissue characterization without any exogenous agent and with high sensitivity and specificity. Proof of concept is presented in using mass spectrometry intraoperatively for real-time measurement of molecular structure and using that tissue characterization method to detect tumor boundaries. Multiple sampling sites within the tumor mass were defined for a patient with a recurrent left frontal oligodendroglioma, World Health Organization grade II with chromosome 1p/19q codeletion, and mass spectrometry data indicated a correlation between lipid constitution and tumor cell prevalence. The mass spectrometry measurements reflect a complex molecular structure and are integrated with frameless stereotaxy and imaging, providing 3-dimensional molecular imaging without systemic injection of any agents, which can be implemented for surgical margins delineation of any organ and with a rapidity that allows real-time analysis.

Enhanced Deployment Strategy for Role-based Hierarchical Application Agents in Wireless Sensor Networks with Established Clusterheads

NASA Astrophysics Data System (ADS)

Gendreau, Audrey

Efficient self-organizing virtual clusterheads that supervise data collection based on their wireless connectivity, risk, and overhead costs, are an important element of Wireless Sensor Networks (WSNs). This function is especially critical during deployment when system resources are allocated to a subsequent application. In the presented research, a model used to deploy intrusion detection capability on a Local Area Network (LAN), in the literature, was extended to develop a role-based hierarchical agent deployment algorithm for a WSN. The resulting model took into consideration the monitoring capability, risk, deployment distribution cost, and monitoring cost associated with each node. Changing the original LAN methodology approach to model a cluster-based sensor network depended on the ability to duplicate a specific parameter that represented the monitoring capability. Furthermore, other parameters derived from a LAN can elevate costs and risk of deployment, as well as jeopardize the success of an application on a WSN. A key component of the approach presented in this research was to reduce the costs when established clusterheads in the network were found to be capable of hosting additional detection agents. In addition, another cost savings component of the study addressed the reduction of vulnerabilities associated with deployment of agents to high volume nodes. The effectiveness of the presented method was validated by comparing it against a type of a power-based scheme that used each node's remaining energy as the deployment value. While available energy is directly related to the model used in the presented method, the study deliberately sought out nodes that were identified with having superior monitoring capability, cost less to create and sustain, and are at low-risk of an attack. This work investigated improving the efficiency of an intrusion detection system (IDS) by using the proposed model to deploy monitoring agents after a temperature sensing application had established the network traffic flow to the sink. The same scenario was repeated using a power-based IDS to compare it against the proposed model. To identify a clusterhead's ability to host monitoring agents after the temperature sensing application terminated, the deployed IDS utilized the communication history and other network factors in order to rank the nodes. Similarly, using the node's communication history, the deployed power-based IDS ranked nodes based on their remaining power. For each individual scenario, and after the IDS application was deployed, the temperature sensing application was run for a second time. This time, to monitor the temperature sensing agents as the data flowed towards the sink, the network traffic was rerouted through the new intrusion detection clusterheads. Consequently, if the clusterheads were shared, the re-routing step was not preformed. Experimental results in this research demonstrated the effectiveness of applying a robust deployment metric to improve upon the energy efficiency of a deployed application in a multi-application WSN. It was found that in the scenarios with the intrusion detection application that utilized the proposed model resulted in more remaining energy than in the scenarios that implemented the power-based IDS. The algorithm especially had a positive impact on the small, dense, and more homogeneous networks. This finding was reinforced by the smaller percentage of new clusterheads that was selected. Essentially, the energy cost of the route to the sink was reduced because the network traffic was rerouted through fewer new clusterheads. Additionally, it was found that the intrusion detection topology that used the proposed approach formed smaller and more connected sets of clusterheads than the power-based IDS. As a consequence, this proposed approach essentially achieved the research objective for enhancing energy use in a multi-application WSN.

An agent-oriented approach to automated mission operations

NASA Technical Reports Server (NTRS)

Truszkowski, Walt; Odubiyi, Jide

1994-01-01

As we plan for the next generation of Mission Operations Control Center (MOCC) systems, there are many opportunities for the increased utilization of innovative knowledge-based technologies. The innovative technology discussed is an advanced use of agent-oriented approaches to the automation of mission operations. The paper presents an overview of this technology and discusses applied operational scenarios currently being investigated and prototyped. A major focus of the current work is the development of a simple user mechanism that would empower operations staff members to create, in real time, software agents to assist them in common, labor intensive operations tasks. These operational tasks would include: handling routine data and information management functions; amplifying the capabilities of a spacecraft analyst/operator to rapidly identify, analyze, and correct spacecraft anomalies by correlating complex data/information sets and filtering error messages; improving routine monitoring and trend analysis by detecting common failure signatures; and serving as a sentinel for spacecraft changes during critical maneuvers enhancing the system's capabilities to support nonroutine operational conditions with minimum additional staff. An agent-based testbed is under development. This testbed will allow us to: (1) more clearly understand the intricacies of applying agent-based technology in support of the advanced automation of mission operations and (2) access the full set of benefits that can be realized by the proper application of agent-oriented technology in a mission operations environment. The testbed under development addresses some of the data management and report generation functions for the Explorer Platform (EP)/Extreme UltraViolet Explorer (EUVE) Flight Operations Team (FOT). We present an overview of agent-oriented technology and a detailed report on the operation's concept for the testbed.

An Acetylcholinesterase-Based Chronoamperometric Biosensor for Fast and Reliable Assay of Nerve Agents

PubMed Central

Pohanka, Miroslav; Adam, Vojtech; Kizek, Rene

2013-01-01

The enzyme acetylcholinesterase (AChE) is an important part of cholinergic nervous system, where it stops neurotransmission by hydrolysis of the neurotransmitter acetylcholine. It is sensitive to inhibition by organophosphate and carbamate insecticides, some Alzheimer disease drugs, secondary metabolites such as aflatoxins and nerve agents used in chemical warfare. When immobilized on a sensor (physico-chemical transducer), it can be used for assay of these inhibitors. In the experiments described herein, an AChE- based electrochemical biosensor using screen printed electrode systems was prepared. The biosensor was used for assay of nerve agents such as sarin, soman, tabun and VX. The limits of detection achieved in a measuring protocol lasting ten minutes were 7.41 × 10−12 mol/L for sarin, 6.31 × 10−12 mol/L for soman, 6.17 × 10−11 mol/L for tabun, and 2.19 × 10−11 mol/L for VX, respectively. The assay was reliable, with minor interferences caused by the organic solvents ethanol, methanol, isopropanol and acetonitrile. Isopropanol was chosen as suitable medium for processing lipophilic samples. PMID:23999806

Fluctuation-Enhanced Sensing for Biological Agent Detection and Identification

DTIC Science & Technology

2009-01-01

method for bacterium detection published earlier; sensing and evaluating the odors of microbes ; and spectral and amplitude distribution analysis of noise...REPORT TYPE 3. DATES COVERED 00-00-2009 to 00-00-2009 4. TITLE AND SUBTITLE Fluctuation-Enhanced Sensing for Biological Agent Detection and...evaluating the odors of microbes ; and spectral and amplitude distribution analysis of noise in light scattering to identify spores based on their

Functionalized graphene oxide quantum dot-PVA hydrogel: a colorimetric sensor for Fe2+, Co2+ and Cu2+ ions

NASA Astrophysics Data System (ADS)

Baruah, Upama; Chowdhury, Devasish

2016-04-01

Functionalized graphene oxide quantum dots (GOQDs)-poly(vinyl alcohol) (PVA) hybrid hydrogels were prepared using a simple, facile and cost-effective strategy. GOQDs bearing different surface functional groups were introduced as the cross-linking agent into the PVA matrix thereby resulting in gelation. The four different types of hybrid hydrogels were prepared using graphene oxide, reduced graphene oxide, ester functionalized graphene oxide and amine functionalized GOQDs as cross-linking agents. It was observed that the hybrid hydrogel prepared with amine functionalized GOQDs was the most stable. The potential applicability of using this solid sensing platform has been subsequently explored in an easy, simple, effective and sensitive method for optical detection of M2+ (Fe2+, Co2+ and Cu2+) in aqueous media involving colorimetric detection. Amine functionalized GOQDs-PVA hybrid hydrogel when put into the corresponding solution of Fe2+, Co2+ and Cu2+ renders brown, orange and blue coloration respectively of the solution detecting the presence of Fe2+, Co2+ and Cu2+ ions in the solution. The minimum detection limit observed was 1 × 10-7 M using UV-visible spectroscopy. Further, the applicability of the sensing material was also tested for a mixture of co-existing ions in solution to demonstrate the practical applicability of the system. Insight into the probable mechanistic pathway involved in the detection process is also being discussed.

Molecular detection of viral causes of encephalitis and meningitis in New York State.

PubMed

Dupuis, Michelle; Hull, Rene; Wang, Heng; Nattanmai, Seela; Glasheen, Bernadette; Fusco, Heather; Dzigua, Lela; Markey, Katie; Tavakoli, Norma P

2011-12-01

The etiology of encephalitis and meningitis, serious diseases of the central nervous system (CNS), in most cases remains unknown. The importance of establishing a diagnosis however, becomes even more important as advances are made in effective therapy. Molecular methods of detection, in particular, PCR, are being used routinely and have established a place in the arsenal of tools for diagnosis of CNS infections. In this study a viral etiological agent was detected by PCR in 340 of the total 2,357 specimens from patients who exhibited symptoms of encephalitis or meningitis. The detection rate increased from 8.9% during the first year of the study to 14.8% during the second year of the study with improved methodology and an expanded panel of viral agents. Methods were enhanced by developing real-time PCR assays (some multiplexed), using increased automation, superior nucleic acid extraction, and reverse transcription (RT) methods, and incorporation of an internal extraction control. Additionally, adenovirus and human herpes virus 6 (HHV-6) were added to the original panel of 10 viruses that included enteroviruses, herpesviruses, and arboviruses. The most common viruses detected were enteroviruses (129; 5.5%), Epstein-Barr virus (EBV) (85; 3.6%), herpes simplex viruses (HSVs) 1 and 2 (67; 2.8%), and varicella zoster virus (VZV) (44; 1.9%). Copyright © 2011 Wiley Periodicals, Inc.

Fluorescence background subtraction technique for hybrid fluorescence molecular tomography/x-ray computed tomography imaging of a mouse model of early stage lung cancer.

PubMed

Ale, Angelique; Ermolayev, Vladimir; Deliolanis, Nikolaos C; Ntziachristos, Vasilis

2013-05-01

The ability to visualize early stage lung cancer is important in the study of biomarkers and targeting agents that could lead to earlier diagnosis. The recent development of hybrid free-space 360-deg fluorescence molecular tomography (FMT) and x-ray computed tomography (XCT) imaging yields a superior optical imaging modality for three-dimensional small animal fluorescence imaging over stand-alone optical systems. Imaging accuracy was improved by using XCT information in the fluorescence reconstruction method. Despite this progress, the detection sensitivity of targeted fluorescence agents remains limited by nonspecific background accumulation of the fluorochrome employed, which complicates early detection of murine cancers. Therefore we examine whether x-ray CT information and bulk fluorescence detection can be combined to increase detection sensitivity. Correspondingly, we research the performance of a data-driven fluorescence background estimator employed for subtraction of background fluorescence from acquisition data. Using mice containing known fluorochromes ex vivo, we demonstrate the reduction of background signals from reconstructed images and sensitivity improvements. Finally, by applying the method to in vivo data from K-ras transgenic mice developing lung cancer, we find small tumors at an early stage compared with reconstructions performed using raw data. We conclude with the benefits of employing fluorescence subtraction in hybrid FMT-XCT for early detection studies.

Performance of Traditional and Molecular Methods for Detecting Biological Agents in Drinking Water

EPA Science Inventory

USGS Report - To reduce the impact from a possible bioterrorist attack on drinking-water supplies, analytical methods are needed to rapidly detect the presence of biological agents in water. To this end, 13 drinking-water samples were collected at 9 water-treatment plants in Ohio...

9 CFR 113.55 - Detection of extraneous agents in Master Seed Virus.

Code of Federal Regulations, 2013 CFR

2013-01-01

... Master Seed Virus. 113.55 Section 113.55 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Ingredient Requirements § 113.55 Detection of extraneous agents in Master Seed Virus...

9 CFR 113.55 - Detection of extraneous agents in Master Seed Virus.

Code of Federal Regulations, 2014 CFR

2014-01-01

... Master Seed Virus. 113.55 Section 113.55 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Ingredient Requirements § 113.55 Detection of extraneous agents in Master Seed Virus...

9 CFR 113.55 - Detection of extraneous agents in Master Seed Virus.

Code of Federal Regulations, 2011 CFR

2011-01-01

... Master Seed Virus. 113.55 Section 113.55 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Ingredient Requirements § 113.55 Detection of extraneous agents in Master Seed Virus...

9 CFR 113.55 - Detection of extraneous agents in Master Seed Virus.

Code of Federal Regulations, 2012 CFR

2012-01-01

... Master Seed Virus. 113.55 Section 113.55 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Ingredient Requirements § 113.55 Detection of extraneous agents in Master Seed Virus...

27 CFR 555.184 - Statements of process and samples.

Code of Federal Regulations, 2011 CFR

2011-04-01

... regard to any plastic explosive or to any detection agent that is to be introduced into a plastic... importer, upon request, to the Director. (b) Samples of any plastic explosive or detection agent shall be..., FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE EXPLOSIVES COMMERCE IN EXPLOSIVES Marking of Plastic...

27 CFR 555.184 - Statements of process and samples.

Code of Federal Regulations, 2012 CFR

2012-04-01

... regard to any plastic explosive or to any detection agent that is to be introduced into a plastic... importer, upon request, to the Director. (b) Samples of any plastic explosive or detection agent shall be..., FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE EXPLOSIVES COMMERCE IN EXPLOSIVES Marking of Plastic...

27 CFR 555.184 - Statements of process and samples.

Code of Federal Regulations, 2013 CFR

2013-04-01

... regard to any plastic explosive or to any detection agent that is to be introduced into a plastic... importer, upon request, to the Director. (b) Samples of any plastic explosive or detection agent shall be..., FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE EXPLOSIVES COMMERCE IN EXPLOSIVES Marking of Plastic...

27 CFR 555.184 - Statements of process and samples.

Code of Federal Regulations, 2014 CFR

2014-04-01

... regard to any plastic explosive or to any detection agent that is to be introduced into a plastic... importer, upon request, to the Director. (b) Samples of any plastic explosive or detection agent shall be..., FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE EXPLOSIVES COMMERCE IN EXPLOSIVES Marking of Plastic...

27 CFR 555.184 - Statements of process and samples.

Code of Federal Regulations, 2010 CFR

2010-04-01

... regard to any plastic explosive or to any detection agent that is to be introduced into a plastic... importer, upon request, to the Director. (b) Samples of any plastic explosive or detection agent shall be..., FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE EXPLOSIVES COMMERCE IN EXPLOSIVES Marking of Plastic...

Nano-LISA for in vitro diagnostic applications

NASA Astrophysics Data System (ADS)

Maswadi, Saher; Glickman, Randolph D.; Elliott, Rowe; Barsalou, Norman

2011-03-01

We previously reported the detection of bacterial antigen with immunoaffinity reactions using laser optoacoustic spectroscopy and antibody-coupled gold nanorods (Ab-NR) as a contrast agent specifically targeted to the antigen of interest. The Nano-LISA (Nanoparticle Linked Immunosorbent Assay) method has been adapted to detect three very common blood-borne viral infectious agents, i.e. human T-lymphotropic virus (HTLV), human immunodeficiency virus (HIV) and hepatitis-B (Hep-B). These agents were used in a model test panel to illustrate the performance of the Nano-LISA technique. A working laboratory prototype of a Nano-LISA microplate reader-sensor was assembled and tested against the panel containing specific antigens of each of the infectious viral agents. Optoacoustic (OA) responses generated by the samples were detected using the probe beam deflection technique, an all-optical, non-contact technique. A LabView graphical user interface was developed for control of the instrument and real-time display of the test results. The detection limit of Nano-LISA is at least 1 ng/ml of viral antigen, and can reach 10 pg/ml, depending on the binding affinity of the specific detection antibody used to synthesize the Ab-NR. The method has sufficient specificity, i.e. the detection reagents do not cross-react with noncomplementary antigens. Thus, the OA microplate reader, incorporating NanoLISA, has adequate detection sensitivity and specificity for use in clinical in vitro diagnostic testing.

Intraoperative Identification of the Parathyroid Gland with a Fluorescence Detection System.

PubMed

Shinden, Yoshiaki; Nakajo, Akihiro; Arima, Hideo; Tanoue, Kiyonori; Hirata, Munetsugu; Kijima, Yuko; Maemura, Kosei; Natsugoe, Shoji

2017-06-01

Intraoperative identification of the difficult-to-spot parathyroid gland is critical during surgery for thyroid and parathyroid disease. Recently, intrinsic fluorescence of the parathyroid gland was identified, and a new method was developed for intraoperative detection of the parathyroid with an original fluorescent detection apparatus. Here, we describe a method for intraoperative detection of the parathyroid using a ready-made photodynamic eye (PDE) system without any fluorescent dye or contrast agents. Seventeen patients who underwent surgical treatment for thyroid or parathyroid disease at Kagoshima University Hospital were enrolled in this study. Intrinsic fluorescence of various tissues was detected with the PDE system. Intraoperative in vivo and ex vivo intrinsic fluorescence of the parathyroid, thyroid, lymph nodes and fat tissues was measured and analyzed. The parathyroid gland had a significantly higher fluorescence intensity than the other tissues, including the thyroid glands, lymph nodes and fat tissues, and we could identify them during surgery using the fluorescence-guided method. Our method could be applicable for two intraoperative clinical procedures: ex vivo tissue identification of parathyroid tissue and in vivo identification of the location of the parathyroid gland, including ectopic glands. The PDE system may be an easy and highly feasible method to identify the parathyroid gland during surgery.

Trace material detection of surfaces via single-beam femtosecond MCARS

NASA Astrophysics Data System (ADS)

Bowman Pilkington, Sherrie S.; Roberson, Stephen D.; Pellegrino, Paul M.

2016-05-01

There is a significant need for the development of optical diagnostics for rapid and accurate detection of chemical species in convoluted systems. In particular, chemical warfare agents and explosive materials are of interest, however, identification of these species is difficult for a wide variety of reasons. Low vapor pressures, for example, cause traditional Raman scattering to be ineffective due to the incredibly long signal collection times that are required. Multiplex Coherent Anti-Stokes Raman Scattering (MCARS) spectroscopy generates a complete Raman spectrum from the material of interest using a combination of a broadband pulse which drives multiple molecular vibrations simultaneously and a narrow band probe pulse. For most species, the complete Raman spectrum can be detected in milliseconds; this makes MCARS an excellent technique for trace material detection in complex systems. In this paper, we present experimental MCARS results on solid state chemical species in complex systems. The 40fs Ti:Sapphire laser used in this study has sufficient output power to produce both the broadband continuum pulse and narrow band probe pulse simultaneously. A series of explosive materials of interest have been identified and compared with spontaneous Raman spectra, showing the specificity and stability of this system.

Sustainable medicines and global health care.

PubMed

Cordell, Geoffrey A

2011-07-01

The global population has now exceeded 7 billion, and forests and other resources around the world are being irreversibly depleted for energy, food, shelter, material goods, and drugs to accommodate population needs. For most of the world's population, plants, based on many well-established systems of medicine, in either crude or extract form, represent the foundation of primary health care for the foreseeable future. Contemporary harvesting methods for medicinal plants are severely depleting these critical indigenous resources. However, maintaining and enhancing the availability of quality medicinal agents on a sustainable basis is an unappreciated public health care concept. To accomplish these goals for future health care, and restore the health of the Earth, a profound paradigm shift is necessary: ALL medicinal agents should be regarded as a sustainable commodity, irrespective of their source. Several approaches to enhancing the availability of safe and efficacious plant-based medicinal agents will be presented including integrated strategies to manifest the four pillars (information, botany, chemistry, and biology) for medicinal plant quality control. These integrated initiatives involve information systems, DNA barcoding, metabolomics, biotechnology, nanotechnology, in-field analysis of medicinal plants, and the application of new detection techniques for the development of medicinal plants with enhanced levels of safe and reproducible biological agents. © Georg Thieme Verlag KG Stuttgart · New York.

An empirically grounded agent based model for modeling directs, conflict detection and resolution operations in air traffic management.

PubMed

Bongiorno, Christian; Miccichè, Salvatore; Mantegna, Rosario N

2017-01-01

We present an agent based model of the Air Traffic Management socio-technical complex system aiming at modeling the interactions between aircraft and air traffic controllers at a tactical level. The core of the model is given by the conflict detection and resolution module and by the directs module. Directs are flight shortcuts that are given by air controllers to speed up the passage of an aircraft within a certain airspace and therefore to facilitate airline operations. Conflicts between flight trajectories can occur for two main reasons: either the planning of the flight trajectory was not sufficiently detailed to rule out all potential conflicts or unforeseen events during the flight require modifications of the flight plan that can conflict with other flight trajectories. Our model performs a local conflict detection and resolution procedure. Once a flight trajectory has been made conflict-free, the model searches for possible improvements of the system efficiency by issuing directs. We give an example of model calibration based on real data. We then provide an illustration of the capability of our model in generating scenario simulations able to give insights about the air traffic management system. We show that the calibrated model is able to reproduce the existence of a geographical localization of air traffic controllers' operations. Finally, we use the model to investigate the relationship between directs and conflict resolutions (i) in the presence of perfect forecast ability of controllers, and (ii) in the presence of some degree of uncertainty in flight trajectory forecast.

An empirically grounded agent based model for modeling directs, conflict detection and resolution operations in air traffic management

PubMed Central

Bongiorno, Christian; Mantegna, Rosario N.

2017-01-01

We present an agent based model of the Air Traffic Management socio-technical complex system aiming at modeling the interactions between aircraft and air traffic controllers at a tactical level. The core of the model is given by the conflict detection and resolution module and by the directs module. Directs are flight shortcuts that are given by air controllers to speed up the passage of an aircraft within a certain airspace and therefore to facilitate airline operations. Conflicts between flight trajectories can occur for two main reasons: either the planning of the flight trajectory was not sufficiently detailed to rule out all potential conflicts or unforeseen events during the flight require modifications of the flight plan that can conflict with other flight trajectories. Our model performs a local conflict detection and resolution procedure. Once a flight trajectory has been made conflict-free, the model searches for possible improvements of the system efficiency by issuing directs. We give an example of model calibration based on real data. We then provide an illustration of the capability of our model in generating scenario simulations able to give insights about the air traffic management system. We show that the calibrated model is able to reproduce the existence of a geographical localization of air traffic controllers’ operations. Finally, we use the model to investigate the relationship between directs and conflict resolutions (i) in the presence of perfect forecast ability of controllers, and (ii) in the presence of some degree of uncertainty in flight trajectory forecast. PMID:28419160

Advances in analytical technologies for environmental protection and public safety.

PubMed

Sadik, O A; Wanekaya, A K; Andreescu, S

2004-06-01

Due to the increased threats of chemical and biological agents of injury by terrorist organizations, a significant effort is underway to develop tools that can be used to detect and effectively combat chemical and biochemical toxins. In addition to the right mix of policies and training of medical personnel on how to recognize symptoms of biochemical warfare agents, the major success in combating terrorism still lies in the prevention, early detection and the efficient and timely response using reliable analytical technologies and powerful therapies for minimizing the effects in the event of an attack. The public and regulatory agencies expect reliable methodologies and devices for public security. Today's systems are too bulky or slow to meet the "detect-to-warn" needs for first responders such as soldiers and medical personnel. This paper presents the challenges in monitoring technologies for warfare agents and other toxins. It provides an overview of how advances in environmental analytical methodologies could be adapted to design reliable sensors for public safety and environmental surveillance. The paths to designing sensors that meet the needs of today's measurement challenges are analyzed using examples of novel sensors, autonomous cell-based toxicity monitoring, 'Lab-on-a-Chip' devices and conventional environmental analytical techniques. Finally, in order to ensure that the public and legal authorities are provided with quality data to make informed decisions, guidelines are provided for assessing data quality and quality assurance using the United States Environmental Protection Agency (US-EPA) methodologies.

The "social" and "interpersonal" body in spatial cognition. The role of agency and interagency.

PubMed

Crivelli, Davide; Balconi, Michela

2015-09-01

In order to interact effectively, we need to represent our action as produced by human beings. According to direct access theories, the first steps of visual information processing offer us an informed direct grasp of the situation, especially when social and interpersonal components are implicated. Biological system detection may be the gateway of such smart processes and then may influence initial stages of perception fostering adaptive social behaviour. To investigate early neural correlates of human agency detection in ecological situations with more high or low social impact, we compared scenes showing a human versus artificial agent interacting with a human agent. Twenty volunteers participated in the study. They were asked to observe dynamic visual stimuli showing realistic interactions. ERP (event-related potentials) were recorded. Each stimulus depicted an arm executing a gesture addressed to a human agent. Visual features of the arm were manipulated: in half of trials, it was real; in other trials, it was deprived of some details and transformed in a statue-like arm. EEG morphological analysis revealed an early negative deflection peaking at about 155 ms. Peak amplitude data have been statistically analysed by repeated-measures ANOVAs. It was found that the peak was ampler in the left inferior posterior region when the gesturing arm was human. The early negative deflection, N150, which we found to be different between the human and artificial conditions, is presumably associated with human agency detection in high interpersonal context.

Miniaturized low-cost ion mobility spectrometer for fast detection of chemical warfare agents.

PubMed

Zimmermann, Stefan; Barth, Sebastian; Baether, Wolfgang K M; Ringer, Joachim

2008-09-01

Ion mobility spectrometry (IMS) is a well-known method for detecting hazardous compounds in air. Typical applications are the detection of chemical warfare agents, highly toxic industrial compounds, explosives, and drugs of abuse. Detection limits in the low part per billion range, fast response times, and simple instrumentation make this technique more and more popular. In particular, there is an increasing demand for miniaturized low-cost IMS for hand-held devices and air monitoring of public areas by sensor networks. In this paper, we present a miniaturized aspiration condenser type ion mobility spectrometer for fast detection of chemical warfare agents. The device is easy to manufacture and allows single substance identification down to low part per billion-level concentrations within seconds. The improved separation power results from ion focusing by means of geometric constraints and fluid dynamics. A simple pattern recognition algorithm is used for the identification of trained substances in air. The device was tested at the German Armed Forces Scientific Institute for Protection Technologies-NBC-Protection. Different chemical warfare agents, such as sarin, tabun, soman, US-VX, sulfur mustard, nitrogen mustard, and lewisite were tested. The results are presented here.

IMS software developments for the detection of chemical warfare agent

NASA Technical Reports Server (NTRS)

Klepel, ST.; Graefenhain, U.; Lippe, R.; Stach, J.; Starrock, V.

1995-01-01

Interference compounds like gasoline, diesel, burning wood or fuel, etc. are presented in common battlefield situations. These compounds can cause detectors to respond as a false positive or interfere with the detector's ability to respond to target compounds such as chemical warfare agents. To ensure proper response of the ion mobility spectrometer to chemical warfare agents, two special software packages were developed and incorporated into the Bruker RAID-1. The programs suppress interferring signals caused by car exhaust or smoke gases resulting from burning materials and correct the influence of variable sample gas humidity which is important for detection and quantification of blister agents like mustard gas or lewisite.

Usefulness of high-density barium for detection of leaks after esophagogastrectomy, total gastrectomy, and total laryngectomy.

PubMed

Swanson, Jonathan O; Levine, Marc S; Redfern, Regina O; Rubesin, Stephen E

2003-08-01

The purpose of this study was to determine the usefulness of a high-density (250% weight/volume) barium compared with a water-soluble contrast agent for the detection of esophageal leaks in patients who had undergone esophagogastrectomy, total gastrectomy, or total laryngectomy. A search of our radiology database from 1998 to 2001 revealed 46 eligible radiographic studies performed using a water-soluble contrast agent alone or a water-soluble contrast agent followed by barium that showed leaks in patients who had undergone esophagogastrectomy, total gastrectomy, or total laryngectomy. The images were reviewed to determine the morphology of the leaks (i.e., blind-ending tracks, sealed-off collections, or free extravasation of contrast material). Medical records were also reviewed to determine whether detection of the leaks seen on the radiographic studies affected patient management. Of the 46 leaks seen on radiographic studies, 23 (50%) were detected with a water-soluble contrast agent and 23 (50%) were detected only with high-density barium. Of the 23 leaks visualized with water-soluble contrast media, six (26%) were characterized by blind-ending tracks, 14 (61%) by sealed-off collections, and three (13%) by free extravasation of contrast material into the mediastinum or neck. Of the 23 leaks visualized only with high-density barium, 19 (83%) were characterized by blind-ending tracks and four (17%) by sealed-off collections. Thus, leaks detected only on images obtained with high-density barium were significantly more likely to be characterized by blind-ending tracks than those detected on images obtained with a water-soluble contrast agent (p = 0.0007). Of the 33 patients with clinical follow-up, the findings seen on these imaging studies affected management in 12 (86%) of 14 patients with leaks depicted by water-soluble contrast media and in 10 (53%) of 19 with leaks depicted only by high-density barium. Our findings support the use of high-density barium as part of the routine postoperative radiographic examination when no leaks are detected on images obtained with a water-soluble contrast agent.

Lightweight autonomous chemical identification system (LACIS)

NASA Astrophysics Data System (ADS)

Lozos, George; Lin, Hai; Burch, Timothy

2012-06-01

Smiths Detection and Intelligent Optical Systems have developed prototypes for the Lightweight Autonomous Chemical Identification System (LACIS) for the US Department of Homeland Security. LACIS is to be a handheld detection system for Chemical Warfare Agents (CWAs) and Toxic Industrial Chemicals (TICs). LACIS is designed to have a low limit of detection and rapid response time for use by emergency responders and could allow determination of areas having dangerous concentration levels and if protective garments will be required. Procedures for protection of responders from hazardous materials incidents require the use of protective equipment until such time as the hazard can be assessed. Such accurate analysis can accelerate operations and increase effectiveness. LACIS is to be an improved point detector employing novel CBRNE detection modalities that includes a militaryproven ruggedized ion mobility spectrometer (IMS) with an array of electro-resistive sensors to extend the range of chemical threats detected in a single device. It uses a novel sensor data fusion and threat classification architecture to interpret the independent sensor responses and provide robust detection at low levels in complex backgrounds with minimal false alarms. The performance of LACIS prototypes have been characterized in independent third party laboratory tests at the Battelle Memorial Institute (BMI, Columbus, OH) and indoor and outdoor field tests at the Nevada National Security Site (NNSS). LACIS prototypes will be entering operational assessment by key government emergency response groups to determine its capabilities versus requirements.

Fitting new technologies into the safety paradigm: use of microarrays in transfusion.

PubMed

Fournier-Wirth, C; Coste, J

2007-01-01

Until the late 1990s, mandatory blood screening for transmissible infectious agents depended entirely on antigen/antibody-based detection assays. The recent emergence of Nucleic acid Amplification Technologies (NAT) has revolutionised viral diagnosis, not only by increasing the level of sensitivity but also by facilitating the detection of several viruses in parallel by multiplexing specific primers. In more complex biological situations, when a broad spectrum of pathogens must be screened, the limitations of these first generation technologies became apparent. High throughput systems, such as DNA Arrays, permit a conceptually new approach. These miniaturised micro systems allow the detection of hundreds of different targets simultaneously, inducing a dramatic decrease in reagent consumption, a reduction in the number of confirmation tests and a simplification of data interpretation. However, the systems currently available require additional instrumentation and reagents for sample preparation and target amplification prior to detection on the DNA array. A major challenge in the area of DNA detection is the development of methods that do not rely on target amplification systems. Likewise, the advances of protein microarrays have lagged because of poor stability of proteins, complex coupling chemistry and weak detection signals. Emerging technologies like Biosensors and nano-particle based DNA or Protein Bio-Barcode Amplification Assays are promising diagnostic tools for a wide range of clinical applications, including blood donation screening.

A new contrast media for functional MR urography: Gd-MAG3.

PubMed

Algin, Oktay

2011-07-01

Tc-99m-MAG3 (tubular agent) provides high imaging quality and extraction efficiency; and has become one of the most widely used agent for scintigraphic examinations of urinary system pathologies and renal transplants. Recently, it was reported that functional magnetic resonance urography (FMRU) can be sufficient in detection of urinary tract obstruction, renal artery stenosis, calculation of kidney functions and evaluation of renal transplants. However the pharmacokinetics of magnetic resonance (MR) contrast-media used in FMRU and Tc-99m-MAG3 differs from each other. This may cause discordant results between the FMRU and most of the scintigraphic studies. To our knowledge, there is no contrast-media which is specific for FMRU. A kidney specific contrast material can be developed for FMRU studies as well. MAG3 is a good candidate for this chelation. In conclusion, MR imaging (MRI) will be the most useful and important technique for morphologic-functional evaluation of urinary system. FMRU examinations performed with MAG3 chelated gadolinium can be sufficient for the complete evaluation of urinary tract even in patients with impaired renal functions ("all in one MRI"). MRI has some important advantages including no risk for radiation exposure, high temporal and spatial resolution, no need for nephrotoxic contrast agent; besides being a fast and feasible technique. Gadolinium-containing contrast agents may cause a life-threatening adverse reaction known as nephrogenic systemic fibrosis in patients with severe renal impairment, but Gd-MAG3 may reduce the risk of nephrogenic systemic fibrosis due to its higher extraction capacity and other features. Copyright © 2011 Elsevier Ltd. All rights reserved.

Reliability of plant root comet assay in comparison with human leukocyte comet assay for assessment environmental genotoxic agents.

PubMed

Reis, Gabriela Barreto Dos; Andrade-Vieira, Larissa Fonseca; Moraes, Isabella de Campos; César, Pedro Henrique Souza; Marcussi, Silvana; Davide, Lisete Chamma

2017-08-01

Comet assay is an efficient test to detect genotoxic compounds based on observation of DNA damage. The aim of this work was to compare the results obtained from the comet assay in two different type of cells extracted from the root tips from Lactuca sativa L. and human blood. For this, Spent Pot Liner (SPL), and its components (aluminum and fluoride) were applied as toxic agents. SPL is a solid waste generated in industry from the aluminum mining and processing with known toxicity. Three concentrations of all tested solutions were applied and the damages observed were compared to negative and positive controls. It was observed an increase in the frequency of DNA damage for human leukocytes and plant cells, in all treatments. On human leukocytes, SPL induced the highest percentage of damage, with an average of 87.68%. For root tips cells of L. sativa the highest percentage of damage was detected for aluminum (93.89%). Considering the arbitrary units (AU), the average of nuclei with high levels of DNA fragmentation was significant for both cells type evaluated. The tested cells demonstrated equal effectiveness for detection of the genotoxicity induced by the SPL and its chemical components, aluminum and fluoride. Further, using a unique method, the comet assay, we proved that cells from root tips of Lactuca sativa represent a reliable model to detect DNA damage induced by genotoxic pollutants is in agreement of those observed in human leukocytes as model. So far, plant cells may be suggested as important system to assess the toxicological risk of environmental agents. Copyright © 2017 Elsevier Inc. All rights reserved.

ELISA assays and alcohol: increasing carbon chain length can interfere with detection of cytokines

PubMed Central

von Maltzan, Kristine; Pruett, Stephen B.

2010-01-01

Enzyme-linked immunosorbent assays (ELISA) are frequently used in studies on cytokine production in response to treatment of cell cultures or laboratory animals. When an ELISA assay is performed on cell culture supernatants, samples often contain the treatment agents. The purpose of the present study was to determine if some of the agents evaluated might inhibit cytokine detection by interfering with the ELISA, leaving the question of whether cytokine production was inhibited unanswered. Mouse and human cytokine ELISA kits from BD Biosciences were used according to the manufacturer’s instructions. Cytokine proteins were subjected to one to five carbon alcohols at 86.8 mM (methanol, ethanol, 1-propanol, 2-propanol, n-butanol, and n-pentanol). After treating cell cultures with alcohols of different carbon chain lengths, we found that some of the alcohols interfered with measurement of some cytokines by ELISA, thus making their effects on cytokine production by cells in culture unclear. Increasing carbon chain length of straight chain alcohols positively correlated with their ability to inhibit detection of TNF-α and IL-10, but not with the detection of IL-6, IL-8, and IL-12. To avoid misinterpretation of treatment effects, ELISA assays should be tested with the reference protein and the treatment agent first, before testing biological samples. These results along with other recent results we obtained using circular dichroism indicate that alcohols with 2 or more carbons can directly alter protein conformation enough to disrupt binding in an ELISA (shown in the present study) or to inhibit ligand induced conformational changes (results not shown). Such direct effects have not been given enough consideration as a mechanism of ethanol action in the immune system. PMID:20843633

Counter-propagating wave interaction for contrast-enhanced ultrasound imaging

NASA Astrophysics Data System (ADS)

Renaud, G.; Bosch, J. G.; ten Kate, G. L.; Shamdasani, V.; Entrekin, R.; de Jong, N.; van der Steen, A. F. W.

2012-11-01

Most techniques for contrast-enhanced ultrasound imaging require linear propagation to detect nonlinear scattering of contrast agent microbubbles. Waveform distortion due to nonlinear propagation impairs their ability to distinguish microbubbles from tissue. As a result, tissue can be misclassified as microbubbles, and contrast agent concentration can be overestimated; therefore, these artifacts can significantly impair the quality of medical diagnoses. Contrary to biological tissue, lipid-coated gas microbubbles used as a contrast agent allow the interaction of two acoustic waves propagating in opposite directions (counter-propagation). Based on that principle, we describe a strategy to detect microbubbles that is free from nonlinear propagation artifacts. In vitro images were acquired with an ultrasound scanner in a phantom of tissue-mimicking material with a cavity containing a contrast agent. Unlike the default mode of the scanner using amplitude modulation to detect microbubbles, the pulse sequence exploiting counter-propagating wave interaction creates no pseudoenhancement behind the cavity in the contrast image.

Masking of endotoxin in surfactant samples: Effects on Limulus-based detection systems.

PubMed

Reich, Johannes; Lang, Pierre; Grallert, Holger; Motschmann, Hubert

2016-09-01

Over the last few decades Limulus Amebocyte Lysate (LAL) has been the most sensitive method for the detection of endotoxins (Lipopolysaccharides) and is well accepted in a broad field of applications. Recently, Low Endotoxin Recovery (LER) in biopharmaceutical drug products has been noticed, whereby the detection of potential endotoxin contaminations is not ensured. Notably, most of these drug products contain surfactants, which can have crucial effects on the detectability of endotoxin. In order to analyze the driving forces of LER, endotoxin detection in samples containing nonionic surfactants in various buffer systems was investigated. The results show that the process of LER is kinetically controlled and temperature-dependent. Furthermore, only the simultaneous presence of nonionic surfactants and components capable of forming metal complexes resulted in LER. In addition, capacity experiments show that even hazardous amounts of endotoxin can remain undetectable within such formulation compositions. In conclusion, the LER phenomenon is caused by endotoxin masking and not by test interference. In this process, the supramolecular structure of endotoxin is altered and exhibits only a limited susceptibility in binding to the Factor C of Limulus-based detection systems. We propose a two-step mechanism of endotoxin masking by complex forming agents and nonionic surfactants. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Nucleic Acid-Based Approaches for Detection of Viral Hepatitis

PubMed Central

Behzadi, Payam; Ranjbar, Reza; Alavian, Seyed Moayed

2014-01-01

Context: To determining suitable nucleic acid diagnostics for individual viral hepatitis agent, an extensive search using related keywords was done in major medical library and data were collected, categorized, and summarized in different sections. Results: Various types of molecular biology tools can be used to detect and quantify viral genomic elements and analyze the sequences. These molecular assays are proper technologies for rapidly detecting viral agents with high accuracy, high sensitivity, and high specificity. Nonetheless, the application of each diagnostic method is completely dependent on viral agent. Conclusions: Despite rapidity, automation, accuracy, cost-effectiveness, high sensitivity, and high specificity of molecular techniques, each type of molecular technology has its own advantages and disadvantages. PMID:25789132

Benzene derivatives produced by Fusarium graminearum - Short communication.

PubMed

Ntushelo, Khayalethu; Setshedi, Itumeleng

2015-06-01

Using NMR spectroscopy benzene derivatives were detected in mycelia of Fusarium graminearum, a pathogen of wheat and maize. In previous studies F. graminearum was found to cause cancer to humans and benzene derivatives were detected in breath of cancer sufferers. Surprisingly, no study found benzene derivatives to be the cancerous agents in F. graminearum. In this study we detected benzene derivatives in F. graminearum and propose to study their role as cancer agents.

Dual Contrast CT Method Enables Diagnostics of Cartilage Injuries and Degeneration Using a Single CT Image.

PubMed

Saukko, Annina E A; Honkanen, Juuso T J; Xu, Wujun; Väänänen, Sami P; Jurvelin, Jukka S; Lehto, Vesa-Pekka; Töyräs, Juha

2017-12-01

Cartilage injuries may be detected using contrast-enhanced computed tomography (CECT) by observing variations in distribution of anionic contrast agent within cartilage. Currently, clinical CECT enables detection of injuries and related post-traumatic degeneration based on two subsequent CT scans. The first scan allows segmentation of articular surfaces and lesions while the latter scan allows evaluation of tissue properties. Segmentation of articular surfaces from the latter scan is difficult since the contrast agent diffusion diminishes the image contrast at surfaces. We hypothesize that this can be overcome by mixing anionic contrast agent (ioxaglate) with bismuth oxide nanoparticles (BINPs) too large to diffuse into cartilage, inducing a high contrast at the surfaces. Here, a dual contrast method employing this mixture is evaluated by determining the depth-wise X-ray attenuation profiles in intact, enzymatically degraded, and mechanically injured osteochondral samples (n = 3 × 10) using a microCT immediately and at 45 min after immersion in contrast agent. BiNPs were unable to diffuse into cartilage, producing high contrast at articular surfaces. Ioxaglate enabled the detection of enzymatic and mechanical degeneration. In conclusion, the dual contrast method allowed detection of injuries and degeneration simultaneously with accurate cartilage segmentation using a single scan conducted at 45 min after contrast agent administration.

Noninvasive, localized, and transient brain drug delivery using focused ultrasound and microbubbles

NASA Astrophysics Data System (ADS)

Choi, James J.

In the United States, Alzheimer's disease (AD), Parkinson's disease (PD), and brain cancer caused 72,432, 19,566 and 12,886 deaths in 2006, respectively. Whereas the number of deaths due to major disorders such as heart disease, stroke, and prostate cancer have decreased since 2006, deaths attributed to AD, PD, and brain cancer have not. Treatment options for patients with CNS disorders remain limited despite significant advances in knowledge of CNS disease pathways and development of neurologically potent agents. One of the major obstacles is that the cerebral microvasculature is lined by a specialized and highly regulated blood-brain barrier (BBB) that prevents large agents from entering the brain extracellular space. The purpose of this dissertation is to design a noninvasive, localized, and transient BBB opening system using focused ultrasound (FUS) and determine ultrasound and microbubble conditions that can effectively and safely deliver large pharmacologically-relevant-sized agents to the brain. To meet this end, an in vivo mouse brain drug delivery system using a stereotactic-based targeting method was developed. FUS was applied noninvasively through the intact skin and skull, which allowed for long-term and high-throughput studies. With this system, more than 150 mice were exposed to one of 31 distinct acoustic and microbubble conditions. The feasibility of delivering a large MRI contrast agent was first demonstrated in vivo in both wild-type and transgenic Alzheimer's disease model (APP/PS1) mice. A wide range of acoustic and microbubble conditions were then evaluated for their ability to deliver agents to a target region. Interestingly, the possible design space of parameters was found to be vast and different conditions resulted in distinct spatial distributions and doses delivered. In particular, BBB opening was shown to be dependent on the microbubble diameter, acoustic pressure, pulse repetition frequency (PRF), and pulse length (PL). Each set of conditions determined both the size of agents that can traverse the BBB, and also the level of safety of the technique. In one set of conditions (peak-rarefactional pressure: 0.61 MPa, PRF: 10 Hz, PL: 20 ms), large 70-kDa dextran was delivered to a target region, but were associated with detectable damaged sites as indicated by dark neurons, microvacuolations, and erythrocyte extravasations. Another set of conditions (peak-rarefactional pressure: 0.46 MPa, PRF: 5 Hz, PL: 0.2 ms) delivered 3-kDa dextran homogeneously and diffusely to a target region in the brain without any detectable dark neurons, microvacuolations, or erythrocyte extravasations. Each distinct set of conditions may thus be used for different clinical application, i.e., treatment of brain cancer and AD. In conclusion, an effective method to noninvasively, locally, and transiently deliver large therapeutic agents through the BBB was developed.

Detection of early changes in lung cell cytology by flow-systems analysis techniques. Progress report, July 1--December 31, 1977

DOE Office of Scientific and Technical Information (OSTI.GOV)

Steinkamp, J.A.; Hansen, K.M.; Wilson, J.S.

1978-04-01

This report summarizes ongoing experiments to develop cytological and biochemical indicators for measuring damage to respiratory tract cells exposed by inhalation of environmental toxic agents. The specific goal of this project is to apply flow cytometric methods to analyze and detect changes in lung epithelium as a function of exposure to toxic agents such as those associated with the production of synthetic fuels from oil shale and coal. The objectives during the past 6 months were to complete modifications to the multiparameter cell separator by adding a krypton laser with an output capability of specific wavelengths ranging from the uvmore » to the ir; analyze and separate lung cells based on their DNA content; evaluate some new fluorescent DNA and protein stains; and treat hamster lung cells with proteolytic enzymes for increasing cell yield. Future experiments will involve the continued analysis and characterization of exfoliated lung cells based primarily on cellular DNA content, protein, morphological features, and specific enzyme activities; quantitation of macrophage activity; exposure of hamsters to toxic agents such as oil shale particulates and ozone; and continued analysis of cells based on DNA content. As this new technology becomes adapted to analyzing respiratory tract cells, the measurement of physical and biochemical cell properties as a function of exposure to toxic agents will be increased. This analytical approach is designed to assist in the establishment of guidelines for estimating risks to exposed humans.« less

Modeling Co-evolution of Speech and Biology.

PubMed

de Boer, Bart

2016-04-01

Two computer simulations are investigated that model interaction of cultural evolution of language and biological evolution of adaptations to language. Both are agent-based models in which a population of agents imitates each other using realistic vowels. The agents evolve under selective pressure for good imitation. In one model, the evolution of the vocal tract is modeled; in the other, a cognitive mechanism for perceiving speech accurately is modeled. In both cases, biological adaptations to using and learning speech evolve, even though the system of speech sounds itself changes at a more rapid time scale than biological evolution. However, the fact that the available acoustic space is used maximally (a self-organized result of cultural evolution) is constant, and therefore biological evolution does have a stable target. This work shows that when cultural and biological traits are continuous, their co-evolution may lead to cognitive adaptations that are strong enough to detect empirically. Copyright © 2016 Cognitive Science Society, Inc.

Fluorine (19F) MRS and MRI in biomedicine.

PubMed

Ruiz-Cabello, Jesús; Barnett, Brad P; Bottomley, Paul A; Bulte, Jeff W M

2011-02-01

Shortly after the introduction of (1)H MRI, fluorinated molecules were tested as MR-detectable tracers or contrast agents. Many fluorinated compounds, which are nontoxic and chemically inert, are now being used in a broad range of biomedical applications, including anesthetics, chemotherapeutic agents, and molecules with high oxygen solubility for respiration and blood substitution. These compounds can be monitored by fluorine ((19)F) MRI and/or MRS, providing a noninvasive means to interrogate associated functions in biological systems. As a result of the lack of endogenous fluorine in living organisms, (19)F MRI of 'hotspots' of targeted fluorinated contrast agents has recently opened up new research avenues in molecular and cellular imaging. This includes the specific targeting and imaging of cellular surface epitopes, as well as MRI cell tracking of endogenous macrophages, injected immune cells and stem cell transplants. Copyright © 2010 John Wiley & Sons, Ltd.

Antibody mimetics: promising complementary agents to animal-sourced antibodies.

PubMed

Baloch, Abdul Rasheed; Baloch, Abdul Wahid; Sutton, Brian J; Zhang, Xiaoying

2016-01-01

Despite their wide use as therapeutic, diagnostic and detection agents, the limitations of polyclonal and monoclonal antibodies have inspired scientists to design the next generation biomedical agents, so-called antibody mimetics that offer many advantages over conventional antibodies. Antibody mimetics can be constructed by protein-directed evolution or fusion of complementarity-determining regions through intervening framework regions. Substantial progress in exploiting human, butterfly (Pieris brassicae) and bacterial systems to design and select mimetics using display technologies has been made in the past 10 years, and one of these mimetics [Kalbitor® (Dyax)] has made its way to market. Many challenges lie ahead to develop mimetics for various biomedical applications, especially those for which conventional antibodies are ineffective, and this review describes the current characteristics, construction and applications of antibody mimetics compared to animal-sourced antibodies. The possible limitations of mimetics and future perspectives are also discussed.

9 CFR 113.43 - Detection of chlamydial agents.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Detection of chlamydial agents. 113.43 Section 113.43 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF... in a filed Outline of Production. (a) The yolk sac of 6-day-old chicken embryos shall be injected...

78 FR 16513 - Application of Advances in Nucleic Acid and Protein Based Detection Methods to Multiplex...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-15

... Transfusion-Transmissible Agents and Blood Cell Antigens in Blood Donations; Public Workshop AGENCY: Food and... Methods to Multiplex Detection of Transfusion- Transmissible Agents and Blood Cell Antigens in Blood... and the use of these tests in blood donor screening and blood cell antigen typing. The public workshop...

Disease-associated prion protein detected in lymphoid tissues from pigs challenged with the agent of chronic wasting disease

USDA-ARS?s Scientific Manuscript database

Aims: Chronic wasting disease (CWD) is a naturally-occurring, fatal neurodegenerative disease of cervids. We previously demonstrated that disease-associated prion protein (PrPSc) can be detected in the brain and retina from pigs challenged intracranially or orally with the CWD agent. In that study,...

The sequential injection system with adsorptive stripping voltammetric detection.

PubMed

Kubiak, W W; Latonen, R M; Ivaska, A

2001-03-16

Two sequential injection systems have been developed for adsorptive stripping voltammetric measurement. One is for substances adsorbing at mercury, e.g. riboflavin. In this case, a simple arrangement with only sample aspiration is needed. Reproducibility was 3% and detection limit 0.07 muM. The measuring system was applied to determination of riboflavin in vitamin pills and to study the photodegradation process of riboflavin in aqueous solutions. In the second case, metal ions were determined. They have to be complexed before deposition on the mercury surface. Thus, both the sample and the ligand have to be aspirated in the system. In this case, the reproducibility was approximately 6% and the detection limit <0.1 ppm for cadmium, lead and copper when complexation with oxine was used. Dimethylglyoxime was used in determination of nickel and cobalt and nioxime complexes were used in determination of nickel and copper. With these complexing agents, the reproducibility was the same as with oxine, but the metals could be determined at concentrations lower than 0.01 ppm. Application of two ligands in a SIA system with AdSV detection was also studied. Simultaneous determination of copper, lead, cadmium and cobalt was possible by using oxine and dimethylglyoxime. Copper and nickel were simultaneously determined by using dimethylglyoxime and nioxime.

Prevalence study of Simkania negevensis in cooling towers in Spain.

PubMed

Pérez, Leonardo Martín; Codony, Francesc; Ríos, Karina; Adrados, Bárbara; Fittipaldi, Mariana; De Dios, Gregori; Peñuela, Gustavo; Morató, Jordi

2011-06-01

Simkania negevensis is an obligate intracellular bacterium grouped into the order Chlamydiales. This new amoeba-resistant intracellular bacterium might represent a novel etiologic agent of bronchiolitis and community-acquired pneumonia and occurs in aquatic habitats such as drinking water and reclaimed wastewater. Another amoeba-related bacterium, Legionella pneumophila, is an etiologic agent of pneumonia transmitted by environmental aerosols or contaminated water/air cooling systems. These transmission pathways are important in the natural history of Legionellae infections and possibly other intracellular microorganisms such as Parachlamydiaceae; thus, understanding the feasibility of Simkania infection by these routes is relevant. In the present work, we investigated the prevalence of this newly identified pathogenic bacterium in cooling towers by quantitative PCR (qPCR) and its possible relationship with Legionella pneumophila co-infection. Our results show Simkania detection in 2 of 70 cooling towers analyzed. To our knowledge, this report is the first describing Simkania negevensis detection in this category of environmental water samples.

Department of Defense Chemical, Biological, Defense Program, Annual Report to Congress, March 2005

DTIC Science & Technology

2005-03-01

nerve agents ( GA , GB, GD, and GF), V type nerve agents , and H (mustard) type blister agents . M8 paper can identify agents through...The M21 RSCAAL is an automatic scanning, passive infrared sensor that detects nerve ( GA , GB, and GD) and blister (H and L) agent vapor clouds...Chief of Staff for Programs GA – tabun, a nerve agent GAO – General Accounting Office GB – sarin, a nerve agent GD – soman, a nerve

Highly efficient amplification of chronic wasting disease agent by protein misfolding cyclical amplification with beads (PMCAb)

USGS Publications Warehouse

Johnson, Chad J.; Aiken, Judd M.; McKenzie, Debbie; Samuel, Michael D.; Pedersen, Joel A.

2012-01-01

Protein misfolding cyclic amplification (PMCA) has emerged as an important technique for detecting low levels of pathogenic prion protein in biological samples. The method exploits the ability of the pathogenic prion protein to convert the normal prion protein to a proteinase K-resistant conformation. Inclusion of Teflon® beads in the PMCA reaction (PMCAb) has been previously shown to increase the sensitivity and robustness of detection for the 263 K and SSLOW strains of hamster-adapted prions. Here, we demonstrate that PMCAb with saponin dramatically increases the sensitivity of detection for chronic wasting disease (CWD) agent without compromising the specificity of the assay (i.e., no false positive results). Addition of Teflon® beads increased the robustness of the PMCA reaction, resulting in a decrease in the variability of PMCA results. Three rounds of serial PMCAb allowed detection of CWD agent from a 6.7×10−13 dilution of 10% brain homogenate (1.3 fg of source brain). Titration of the same brain homogenate in transgenic mice expressing cervid prion protein (Tg(CerPrP)1536+/−mice) allowed detection of CWD agent from the 10−6 dilution of 10% brain homogenate. PMCAb is, thus, more sensitive than bioassay in transgenic mice by a factor exceeding 105. Additionally, we are able to amplify CWD agent from brain tissue and lymph nodes of CWD-positive white-tailed deer having Prnp alleles associated with reduced disease susceptibility.