An Energy-Efficient MAC Protocol Using Dynamic Queue Management for Delay-Tolerant Mobile Sensor Networks

PubMed Central

Li, Jie; Li, Qiyue; Qu, Yugui; Zhao, Baohua

2011-01-01

Conventional MAC protocols for wireless sensor network perform poorly when faced with a delay-tolerant mobile network environment. Characterized by a highly dynamic and sparse topology, poor network connectivity as well as data delay-tolerance, delay-tolerant mobile sensor networks exacerbate the severe power constraints and memory limitations of nodes. This paper proposes an energy-efficient MAC protocol using dynamic queue management (EQ-MAC) for power saving and data queue management. Via data transfers initiated by the target sink and the use of a dynamic queue management strategy based on priority, EQ-MAC effectively avoids untargeted transfers, increases the chance of successful data transmission, and makes useful data reach the target terminal in a timely manner. Experimental results show that EQ-MAC has high energy efficiency in comparison with a conventional MAC protocol. It also achieves a 46% decrease in packet drop probability, 79% increase in system throughput, and 25% decrease in mean packet delay. PMID:22319385

Synthesizing Existing CSMA and TDMA Based MAC Protocols for VANETs

PubMed Central

Huang, Jiawei; Li, Qi; Zhong, Shaohua; Liu, Lianhai; Zhong, Ping; Wang, Jianxin; Ye, Jin

2017-01-01

Many Carrier Sense Multiple Access (CSMA) and Time Division Multiple Access (TDMA) based medium access control (MAC) protocols for vehicular ad hoc networks (VANETs) have been proposed recently. Contrary to the common perception that they are competitors, we argue that the underlying strategies used in these MAC protocols are complementary. Based on this insight, we design CTMAC, a MAC protocol that synthesizes existing strategies; namely, random accessing channel (used in CSMA-style protocols) and arbitral reserving channel (used in TDMA-based protocols). CTMAC swiftly changes its strategy according to the vehicle density, and its performance is better than the state-of-the-art protocols. We evaluate CTMAC using at-scale simulations. Our results show that CTMAC reduces the channel completion time and increases the network goodput by 45% for a wide range of application workloads and network settings. PMID:28208590

A Power-Optimized Cooperative MAC Protocol for Lifetime Extension in Wireless Sensor Networks.

PubMed

Liu, Kai; Wu, Shan; Huang, Bo; Liu, Feng; Xu, Zhen

2016-10-01

In wireless sensor networks, in order to satisfy the requirement of long working time of energy-limited nodes, we need to design an energy-efficient and lifetime-extended medium access control (MAC) protocol. In this paper, a node cooperation mechanism that one or multiple nodes with higher channel gain and sufficient residual energy help a sender relay its data packets to its recipient is employed to achieve this objective. We first propose a transmission power optimization algorithm to prolong network lifetime by optimizing the transmission powers of the sender and its cooperative nodes to maximize their minimum residual energy after their data packet transmissions. Based on it, we propose a corresponding power-optimized cooperative MAC protocol. A cooperative node contention mechanism is designed to ensure that the sender can effectively select a group of cooperative nodes with the lowest energy consumption and the best channel quality for cooperative transmissions, thus further improving the energy efficiency. Simulation results show that compared to typical MAC protocol with direct transmissions and energy-efficient cooperative MAC protocol, the proposed cooperative MAC protocol can efficiently improve the energy efficiency and extend the network lifetime.

A Power-Optimized Cooperative MAC Protocol for Lifetime Extension in Wireless Sensor Networks

PubMed Central

Liu, Kai; Wu, Shan; Huang, Bo; Liu, Feng; Xu, Zhen

2016-01-01

In wireless sensor networks, in order to satisfy the requirement of long working time of energy-limited nodes, we need to design an energy-efficient and lifetime-extended medium access control (MAC) protocol. In this paper, a node cooperation mechanism that one or multiple nodes with higher channel gain and sufficient residual energy help a sender relay its data packets to its recipient is employed to achieve this objective. We first propose a transmission power optimization algorithm to prolong network lifetime by optimizing the transmission powers of the sender and its cooperative nodes to maximize their minimum residual energy after their data packet transmissions. Based on it, we propose a corresponding power-optimized cooperative MAC protocol. A cooperative node contention mechanism is designed to ensure that the sender can effectively select a group of cooperative nodes with the lowest energy consumption and the best channel quality for cooperative transmissions, thus further improving the energy efficiency. Simulation results show that compared to typical MAC protocol with direct transmissions and energy-efficient cooperative MAC protocol, the proposed cooperative MAC protocol can efficiently improve the energy efficiency and extend the network lifetime. PMID:27706079

An extended smart utilization medium access control (ESU-MAC) protocol for ad hoc wireless systems

NASA Astrophysics Data System (ADS)

Vashishtha, Jyoti; Sinha, Aakash

2006-05-01

The demand for spontaneous setup of a wireless communication system has increased in recent years for areas like battlefield, disaster relief operations etc., where a pre-deployment of network infrastructure is difficult or unavailable. A mobile ad-hoc network (MANET) is a promising solution, but poses a lot of challenges for all the design layers, specifically medium access control (MAC) layer. Recent existing works have used the concepts of multi-channel and power control in designing MAC layer protocols. SU-MAC developed by the same authors, efficiently uses the 'available' data and control bandwidth to send control information and results in increased throughput via decreasing contention on the control channel. However, SU-MAC protocol was limited for static ad-hoc network and also faced the busy-receiver node problem. We present the Extended SU-MAC (ESU-MAC) protocol which works mobile nodes. Also, we significantly improve the scheme of control information exchange in ESU-MAC to overcome the busy-receiver node problem and thus, further avoid the blockage of control channel for longer periods of time. A power control scheme is used as before to reduce interference and to effectively re-use the available bandwidth. Simulation results show that ESU-MAC protocol is promising for mobile, ad-hoc network in terms of reduced contention at the control channel and improved throughput because of channel re-use. Results show a considerable increase in throughput compared to SU-MAC which could be attributed to increased accessibility of control channel and improved utilization of data channels due to superior control information exchange scheme.

Pliable Cognitive MAC for Heterogeneous Adaptive Cognitive Radio Sensor Networks.

PubMed

Al-Medhwahi, Mohammed; Hashim, Fazirulhisyam; Ali, Borhanuddin Mohd; Sali, Aduwati

2016-01-01

The rapid expansion of wireless monitoring and surveillance applications in several domains reinforces the trend of exploiting emerging technologies such as the cognitive radio. However, these technologies have to adjust their working concepts to consider the common characteristics of conventional wireless sensor networks (WSNs). The cognitive radio sensor network (CRSN), still an immature technology, has to deal with new networks that might have different types of data, traffic patterns, or quality of service (QoS) requirements. In this paper, we design and model a new cognitive radio-based medium access control (MAC) algorithm dealing with the heterogeneous nature of the developed networks in terms of either the traffic pattern or the required QoS for the node applications. The proposed algorithm decreases the consumed power on several fronts, provides satisfactory levels of latency and spectrum utilization with efficient scheduling, and manages the radio resources for various traffic conditions. An intensive performance evaluation is conducted to study the impact of key parameters such as the channel idle time length, node density, and the number of available channels. The performance evaluation of the proposed algorithm shows a better performance than the comparable protocols. Moreover, the results manifest that the proposed algorithm is suitable for real time monitoring applications.

Pliable Cognitive MAC for Heterogeneous Adaptive Cognitive Radio Sensor Networks

PubMed Central

Ali, Borhanuddin Mohd; Sali, Aduwati

2016-01-01

The rapid expansion of wireless monitoring and surveillance applications in several domains reinforces the trend of exploiting emerging technologies such as the cognitive radio. However, these technologies have to adjust their working concepts to consider the common characteristics of conventional wireless sensor networks (WSNs). The cognitive radio sensor network (CRSN), still an immature technology, has to deal with new networks that might have different types of data, traffic patterns, or quality of service (QoS) requirements. In this paper, we design and model a new cognitive radio-based medium access control (MAC) algorithm dealing with the heterogeneous nature of the developed networks in terms of either the traffic pattern or the required QoS for the node applications. The proposed algorithm decreases the consumed power on several fronts, provides satisfactory levels of latency and spectrum utilization with efficient scheduling, and manages the radio resources for various traffic conditions. An intensive performance evaluation is conducted to study the impact of key parameters such as the channel idle time length, node density, and the number of available channels. The performance evaluation of the proposed algorithm shows a better performance than the comparable protocols. Moreover, the results manifest that the proposed algorithm is suitable for real time monitoring applications. PMID:27257964

Adaptive low-power listening MAC protocol based on transmission rates.

PubMed

Hwang, Kwang-il; Yi, Gangman

2014-01-01

Even though existing low-power listening (LPL) protocols have enabled ultra-low-power operation in wireless sensor networks (WSN), they do not address trade-off between energy and delay, since they focused only on energy aspect. However, in recent years, a growing interest in various WSN applications is requiring new design factors, such as minimum delay and higher reliability, as well as energy efficiency. Therefore, in this paper we propose a novel sensor multiple access control (MAC) protocol, transmission rate based adaptive low-power listening MAC protocol (TRA-MAC), which is a kind of preamble-based LPL but is capable of controlling preamble sensing cycle adaptively to transmission rates. Through experiments, it is demonstrated that TRA-MAC enables LPL cycle (LC) and preamble transmission length to adapt dynamically to varying transmission rates, compensating trade-off between energy and response time.

ZeroCal: Automatic MAC Protocol Calibration

NASA Astrophysics Data System (ADS)

Meier, Andreas; Woehrle, Matthias; Zimmerling, Marco; Thiele, Lothar

Sensor network MAC protocols are typically configured for an intended deployment scenario once and for all at compile time. This approach, however, leads to suboptimal performance if the network conditions deviate from the expectations. We present ZeroCal, a distributed algorithm that allows nodes to dynamically adapt to variations in traffic volume. Using ZeroCal, each node autonomously configures its MAC protocol at runtime, thereby trying to reduce the maximum energy consumption among all nodes. While the algorithm is readily usable for any asynchronous low-power listening or low-power probing protocol, we validate and demonstrate the effectiveness of ZeroCal on X-MAC. Extensive testbed experiments and simulations indicate that ZeroCal quickly adapts to traffic variations. We further show that ZeroCal extends network lifetime by 50% compared to an optimal configuration with identical and static MAC parameters at all nodes.

W-MAC: A Workload-Aware MAC Protocol for Heterogeneous Convergecast in Wireless Sensor Networks

PubMed Central

Xia, Ming; Dong, Yabo; Lu, Dongming

2011-01-01

The power consumption and latency of existing MAC protocols for wireless sensor networks (WSNs) are high in heterogeneous convergecast, where each sensor node generates different amounts of data in one convergecast operation. To solve this problem, we present W-MAC, a workload-aware MAC protocol for heterogeneous convergecast in WSNs. A subtree-based iterative cascading scheduling mechanism and a workload-aware time slice allocation mechanism are proposed to minimize the power consumption of nodes, while offering a low data latency. In addition, an efficient schedule adjustment mechanism is provided for adapting to data traffic variation and network topology change. Analytical and simulation results show that the proposed protocol provides a significant energy saving and latency reduction in heterogeneous convergecast, and can effectively support data aggregation to further improve the performance. PMID:22163753

I-MAC: an incorporation MAC for wireless sensor networks

NASA Astrophysics Data System (ADS)

Zhao, Jumin; Li, Yikun; Li, Dengao; Lin, Xiaojie

2017-11-01

This paper proposes an innovative MAC protocol called I-MAC. Protocol for wireless sensor networks, which combines the advantages of collision tolerance and collision cancellation. The protocol increases the number of antenna in wireless sensor nodes. The purpose is to monitor the occurrence of packet collisions by increasing the number of antenna in real time. The built-in identity structure is used in the frame structure in order to help the sending node to identify the location of the receiving node after a data packet collision is detected. Packets can be recovered from where the conflict occurred. In this way, we can monitor the conflict for a fixed period of time. It can improve the channel utilisation through changing the transmission probability of collision nodes and solve the problem of hidden terminal through collision feedback mechanism. We have evaluated our protocol. Our results show that the throughput of I-MAC is 5 percentage points higher than that of carrier sense multiple access/collision notification. The network utilisation of I-MAC is more than 92%.

An ultra low-power and traffic-adaptive medium access control protocol for wireless body area network.

PubMed

Ullah, Sana; Kwak, Kyung Sup

2012-06-01

Wireless Body Area Network (WBAN) consists of low-power, miniaturized, and autonomous wireless sensor nodes that enable physicians to remotely monitor vital signs of patients and provide real-time feedback with medical diagnosis and consultations. It is the most reliable and cheaper way to take care of patients suffering from chronic diseases such as asthma, diabetes and cardiovascular diseases. Some of the most important attributes of WBAN is low-power consumption and delay. This can be achieved by introducing flexible duty cycling techniques on the energy constraint sensor nodes. Stated otherwise, low duty cycle nodes should not receive frequent synchronization and control packets if they have no data to send/receive. In this paper, we introduce a Traffic-adaptive MAC protocol (TaMAC) by taking into account the traffic information of the sensor nodes. The protocol dynamically adjusts the duty cycle of the sensor nodes according to their traffic-patterns, thus solving the idle listening and overhearing problems. The traffic-patterns of all sensor nodes are organized and maintained by the coordinator. The TaMAC protocol is supported by a wakeup radio that is used to accommodate emergency and on-demand events in a reliable manner. The wakeup radio uses a separate control channel along with the data channel and therefore it has considerably low power consumption requirements. Analytical expressions are derived to analyze and compare the performance of the TaMAC protocol with the well-known beacon-enabled IEEE 802.15.4 MAC, WiseMAC, and SMAC protocols. The analytical derivations are further validated by simulation results. It is shown that the TaMAC protocol outperforms all other protocols in terms of power consumption and delay.

Energy Efficient Medium Access Control Protocol for Clustered Wireless Sensor Networks with Adaptive Cross-Layer Scheduling.

PubMed

Sefuba, Maria; Walingo, Tom; Takawira, Fambirai

2015-09-18

This paper presents an Energy Efficient Medium Access Control (MAC) protocol for clustered wireless sensor networks that aims to improve energy efficiency and delay performance. The proposed protocol employs an adaptive cross-layer intra-cluster scheduling and an inter-cluster relay selection diversity. The scheduling is based on available data packets and remaining energy level of the source node (SN). This helps to minimize idle listening on nodes without data to transmit as well as reducing control packet overhead. The relay selection diversity is carried out between clusters, by the cluster head (CH), and the base station (BS). The diversity helps to improve network reliability and prolong the network lifetime. Relay selection is determined based on the communication distance, the remaining energy and the channel quality indicator (CQI) for the relay cluster head (RCH). An analytical framework for energy consumption and transmission delay for the proposed MAC protocol is presented in this work. The performance of the proposed MAC protocol is evaluated based on transmission delay, energy consumption, and network lifetime. The results obtained indicate that the proposed MAC protocol provides improved performance than traditional cluster based MAC protocols.

Energy Efficient Medium Access Control Protocol for Clustered Wireless Sensor Networks with Adaptive Cross-Layer Scheduling

PubMed Central

Sefuba, Maria; Walingo, Tom; Takawira, Fambirai

2015-01-01

This paper presents an Energy Efficient Medium Access Control (MAC) protocol for clustered wireless sensor networks that aims to improve energy efficiency and delay performance. The proposed protocol employs an adaptive cross-layer intra-cluster scheduling and an inter-cluster relay selection diversity. The scheduling is based on available data packets and remaining energy level of the source node (SN). This helps to minimize idle listening on nodes without data to transmit as well as reducing control packet overhead. The relay selection diversity is carried out between clusters, by the cluster head (CH), and the base station (BS). The diversity helps to improve network reliability and prolong the network lifetime. Relay selection is determined based on the communication distance, the remaining energy and the channel quality indicator (CQI) for the relay cluster head (RCH). An analytical framework for energy consumption and transmission delay for the proposed MAC protocol is presented in this work. The performance of the proposed MAC protocol is evaluated based on transmission delay, energy consumption, and network lifetime. The results obtained indicate that the proposed MAC protocol provides improved performance than traditional cluster based MAC protocols. PMID:26393608

Cooperative Energy Harvesting-Adaptive MAC Protocol for WBANs

PubMed Central

Esteves, Volker; Antonopoulos, Angelos; Kartsakli, Elli; Puig-Vidal, Manel; Miribel-Català, Pere; Verikoukis, Christos

2015-01-01

In this paper, we introduce a cooperative medium access control (MAC) protocol, named cooperative energy harvesting (CEH)-MAC, that adapts its operation to the energy harvesting (EH) conditions in wireless body area networks (WBANs). In particular, the proposed protocol exploits the EH information in order to set an idle time that allows the relay nodes to charge their batteries and complete the cooperation phase successfully. Extensive simulations have shown that CEH-MAC significantly improves the network performance in terms of throughput, delay and energy efficiency compared to the cooperative operation of the baseline IEEE 802.15.6 standard. PMID:26029950

Intrusion Detection for Defense at the MAC and Routing Layers of Wireless Networks

DTIC Science & Technology

2007-01-01

Space DoS Denial of Service DSR Dynamic Source Routing IDS Intrusion Detection System LAR Location-Aided Routing MAC Media Access Control MACA Multiple...different mobility parameters. 10 They simulate interaction between three MAC protocols ( MACA , 802.11 and CSMA) and three routing protocols (AODV, DSR

A Cross-Layer Duty Cycle MAC Protocol Supporting a Pipeline Feature for Wireless Sensor Networks

PubMed Central

Tong, Fei; Xie, Rong; Shu, Lei; Kim, Young-Chon

2011-01-01

Although the conventional duty cycle MAC protocols for Wireless Sensor Networks (WSNs) such as RMAC perform well in terms of saving energy and reducing end-to-end delivery latency, they were designed independently and require an extra routing protocol in the network layer to provide path information for the MAC layer. In this paper, we propose a new cross-layer duty cycle MAC protocol with data forwarding supporting a pipeline feature (P-MAC) for WSNs. P-MAC first divides the whole network into many grades around the sink. Each node identifies its grade according to its logical hop distance to the sink and simultaneously establishes a sleep/wakeup schedule using the grade information. Those nodes in the same grade keep the same schedule, which is staggered with the schedule of the nodes in the adjacent grade. Then a variation of the RTS/CTS handshake mechanism is used to forward data continuously in a pipeline fashion from the higher grade to the lower grade nodes and finally to the sink. No extra routing overhead is needed, thus increasing the network scalability while maintaining the superiority of duty-cycling. The simulation results in OPNET show that P-MAC has better performance than S-MAC and RMAC in terms of packet delivery latency and energy efficiency. PMID:22163895

Potential of Wake-Up Radio-Based MAC Protocols for Implantable Body Sensor Networks (IBSN)—A Survey

PubMed Central

Karuppiah Ramachandran, Vignesh Raja; Ayele, Eyuel D.; Meratnia, Nirvana; Havinga, Paul J. M.

2016-01-01

With the advent of nano-technology, medical sensors and devices are becoming highly miniaturized. Consequently, the number of sensors and medical devices being implanted to accurately monitor and diagnose a disease is increasing. By measuring the symptoms and controlling a medical device as close as possible to the source, these implantable devices are able to save lives. A wireless link between medical sensors and implantable medical devices is essential in the case of closed-loop medical devices, in which symptoms of the diseases are monitored by sensors that are not placed in close proximity of the therapeutic device. Medium Access Control (MAC) is crucial to make it possible for several medical devices to communicate using a shared wireless medium in such a way that minimum delay, maximum throughput, and increased network life-time are guaranteed. To guarantee this Quality of Service (QoS), the MAC protocols control the main sources of limited resource wastage, namely the idle-listening, packet collisions, over-hearing, and packet loss. Traditional MAC protocols designed for body sensor networks are not directly applicable to Implantable Body Sensor Networks (IBSN) because of the dynamic nature of the radio channel within the human body and the strict QoS requirements of IBSN applications. Although numerous MAC protocols are available in the literature, the majority of them are designed for Body Sensor Network (BSN) and Wireless Sensor Network (WSN). To the best of our knowledge, there is so far no research paper that explores the impact of these MAC protocols specifically for IBSN. MAC protocols designed for implantable devices are still in their infancy and one of their most challenging objectives is to be ultra-low-power. One of the technological solutions to achieve this objective so is to integrate the concept of Wake-up radio (WuR) into the MAC design. In this survey, we present a taxonomy of MAC protocols based on their use of WuR technology and identify their bottlenecks to be used in IBSN applications. Furthermore, we present a number of open research challenges and requirements for designing an energy-efficient and reliable wireless communication protocol for IBSN. PMID:27916822

Potential of Wake-Up Radio-Based MAC Protocols for Implantable Body Sensor Networks (IBSN)-A Survey.

PubMed

Karuppiah Ramachandran, Vignesh Raja; Ayele, Eyuel D; Meratnia, Nirvana; Havinga, Paul J M

2016-11-29

With the advent of nano-technology, medical sensors and devices are becoming highly miniaturized. Consequently, the number of sensors and medical devices being implanted to accurately monitor and diagnose a disease is increasing. By measuring the symptoms and controlling a medical device as close as possible to the source, these implantable devices are able to save lives. A wireless link between medical sensors and implantable medical devices is essential in the case of closed-loop medical devices, in which symptoms of the diseases are monitored by sensors that are not placed in close proximity of the therapeutic device. Medium Access Control (MAC) is crucial to make it possible for several medical devices to communicate using a shared wireless medium in such a way that minimum delay, maximum throughput, and increased network life-time are guaranteed. To guarantee this Quality of Service (QoS), the MAC protocols control the main sources of limited resource wastage, namely the idle-listening, packet collisions, over-hearing, and packet loss. Traditional MAC protocols designed for body sensor networks are not directly applicable to Implantable Body Sensor Networks (IBSN) because of the dynamic nature of the radio channel within the human body and the strict QoS requirements of IBSN applications. Although numerous MAC protocols are available in the literature, the majority of them are designed for Body Sensor Network (BSN) and Wireless Sensor Network (WSN). To the best of our knowledge, there is so far no research paper that explores the impact of these MAC protocols specifically for IBSN. MAC protocols designed for implantable devices are still in their infancy and one of their most challenging objectives is to be ultra-low-power. One of the technological solutions to achieve this objective so is to integrate the concept of Wake-up radio (WuR) into the MAC design. In this survey, we present a taxonomy of MAC protocols based on their use of WuR technology and identify their bottlenecks to be used in IBSN applications. Furthermore, we present a number of open research challenges and requirements for designing an energy-efficient and reliable wireless communication protocol for IBSN.

A network architecture for precision formation flying using the IEEE 802.11 MAC Protocol

NASA Technical Reports Server (NTRS)

Clare, Loren P.; Gao, Jay L.; Jennings, Esther H.; Okino, Clayton

2005-01-01

Precision Formation Flying missions involve the tracking and maintenance of spacecraft in a desired geometric formation. The strong coupling of spacecraft in formation flying control requires inter-spacecraft communication to exchange information. In this paper, we present a network architecture that supports PFF control, from the initial random deployment phase to the final formation. We show that a suitable MAC layer for the application protocol is IEEE's 802.11 MAC protocol. IEEE 802.11 MAC has two modes of operations: DCF and PCF. We show that DCF is suitable for the initial deployment phase while switching to PCF when the spacecraft are in formation improves jitter and throughput. We also consider the effect of routing on protocol performance and suggest when it is profitable to turn off route discovery to achieve better network performance.

An Enhanced Reservation-Based MAC Protocol for IEEE 802.15.4 Networks

PubMed Central

Afonso, José A.; Silva, Helder D.; Macedo, Pedro; Rocha, Luis A.

2011-01-01

The IEEE 802.15.4 Medium Access Control (MAC) protocol is an enabling standard for wireless sensor networks. In order to support applications requiring dedicated bandwidth or bounded delay, it provides a reservation-based scheme named Guaranteed Time Slot (GTS). However, the GTS scheme presents some drawbacks, such as inefficient bandwidth utilization and support to a maximum of only seven devices. This paper presents eLPRT (enhanced Low Power Real Time), a new reservation-based MAC protocol that introduces several performance enhancing features in comparison to the GTS scheme. This MAC protocol builds on top of LPRT (Low Power Real Time) and includes various mechanisms designed to increase data transmission reliability against channel errors, improve bandwidth utilization and increase the number of supported devices. A motion capture system based on inertial and magnetic sensors has been used to validate the protocol. The effectiveness of the performance enhancements introduced by each of the new features is demonstrated through the provision of both simulation and experimental results. PMID:22163826

Channel MAC Protocol for Opportunistic Communication in Ad Hoc Wireless Networks

NASA Astrophysics Data System (ADS)

Ashraf, Manzur; Jayasuriya, Aruna; Perreau, Sylvie

2008-12-01

Despite significant research effort, the performance of distributed medium access control methods has failed to meet theoretical expectations. This paper proposes a protocol named "Channel MAC" performing a fully distributed medium access control based on opportunistic communication principles. In this protocol, nodes access the channel when the channel quality increases beyond a threshold, while neighbouring nodes are deemed to be silent. Once a node starts transmitting, it will keep transmitting until the channel becomes "bad." We derive an analytical throughput limit for Channel MAC in a shared multiple access environment. Furthermore, three performance metrics of Channel MAC—throughput, fairness, and delay—are analysed in single hop and multihop scenarios using NS2 simulations. The simulation results show throughput performance improvement of up to 130% with Channel MAC over IEEE 802.11. We also show that the severe resource starvation problem (unfairness) of IEEE 802.11 in some network scenarios is reduced by the Channel MAC mechanism.

TraPy-MAC: Traffic Priority Aware Medium Access Control Protocol for Wireless Body Area Network.

PubMed

Ullah, Fasee; Abdullah, Abdul Hanan; Kaiwartya, Omprakash; Cao, Yue

2017-06-01

Recently, Wireless Body Area Network (WBAN) has witnessed significant attentions in research and product development due to the growing number of sensor-based applications in healthcare domain. Design of efficient and effective Medium Access Control (MAC) protocol is one of the fundamental research themes in WBAN. Static on-demand slot allocation to patient data is the main approach adopted in the design of MAC protocol in literature, without considering the type of patient data specifically the level of severity on patient data. This leads to the degradation of the performance of MAC protocols considering effectiveness and traffic adjustability in realistic medical environments. In this context, this paper proposes a Traffic Priority-Aware MAC (TraPy-MAC) protocol for WBAN. It classifies patient data into emergency and non-emergency categories based on the severity of patient data. The threshold value aided classification considers a number of parameters including type of sensor, body placement location, and data transmission time for allocating dedicated slots patient data. Emergency data are not required to carry out contention and slots are allocated by giving the due importance to threshold value of vital sign data. The contention for slots is made efficient in case of non-emergency data considering threshold value in slot allocation. Moreover, the slot allocation to emergency and non-emergency data are performed parallel resulting in performance gain in channel assignment. Two algorithms namely, Detection of Severity on Vital Sign data (DSVS), and ETS Slots allocation based on the Severity on Vital Sign (ETS-SVS) are developed for calculating threshold value and resolving the conflicts of channel assignment, respectively. Simulations are performed in ns2 and results are compared with the state-of-the-art MAC techniques. Analysis of results attests the benefit of TraPy-MAC in comparison with the state-of-the-art MAC in channel assignment in realistic medical environments.

A Very Low Power MAC (VLPM) Protocol for Wireless Body Area Networks

PubMed Central

Ullah, Niamat; Khan, Pervez; Kwak, Kyung Sup

2011-01-01

Wireless Body Area Networks (WBANs) consist of a limited number of battery operated nodes that are used to monitor the vital signs of a patient over long periods of time without restricting the patient’s movements. They are an easy and fast way to diagnose the patient’s status and to consult the doctor. Device as well as network lifetime are among the most important factors in a WBAN. Prolonging the lifetime of the WBAN strongly depends on controlling the energy consumption of sensor nodes. To achieve energy efficiency, low duty cycle MAC protocols are used, but for medical applications, especially in the case of pacemakers where data have time-limited relevance, these protocols increase latency which is highly undesirable and leads to system instability. In this paper, we propose a low power MAC protocol (VLPM) based on existing wakeup radio approaches which reduce energy consumption as well as improving the response time of a node. We categorize the traffic into uplink and downlink traffic. The nodes are equipped with both a low power wake-up transmitter and receiver. The low power wake-up receiver monitors the activity on channel all the time with a very low power and keeps the MCU (Micro Controller Unit) along with main radio in sleep mode. When a node [BN or BNC (BAN Coordinator)] wants to communicate with another node, it uses the low-power radio to send a wakeup packet, which will prompt the receiver to power up its primary radio to listen for the message that follows shortly. The wake-up packet contains the desired node’s ID along with some other information to let the targeted node to wake-up and take part in communication and let all other nodes to go to sleep mode quickly. The VLPM protocol is proposed for applications having low traffic conditions. For high traffic rates, optimization is needed. Analytical results show that the proposed protocol outperforms both synchronized and unsynchronized MAC protocols like T-MAC, SCP-MAC, B-MAC and X-MAC in terms of energy consumption and response time. PMID:22163818

MQ-MAC: A Multi-Constrained QoS-Aware Duty Cycle MAC for Heterogeneous Traffic in Wireless Sensor Networks

PubMed Central

Monowar, Muhammad Mostafa; Rahman, Md. Obaidur; Hong, Choong Seon; Lee, Sungwon

2010-01-01

Energy conservation is one of the striking research issues now-a-days for power constrained wireless sensor networks (WSNs) and hence, several duty-cycle based MAC protocols have been devised for WSNs in the last few years. However, assimilation of diverse applications with different QoS requirements (i.e., delay and reliability) within the same network also necessitates in devising a generic duty-cycle based MAC protocol that can achieve both the delay and reliability guarantee, termed as multi-constrained QoS, while preserving the energy efficiency. To address this, in this paper, we propose a Multi-constrained QoS-aware duty-cycle MAC for heterogeneous traffic in WSNs (MQ-MAC). MQ-MAC classifies the traffic based on their multi-constrained QoS demands. Through extensive simulation using ns-2 we evaluate the performance of MQ-MAC. MQ-MAC provides the desired delay and reliability guarantee according to the nature of the traffic classes as well as achieves energy efficiency. PMID:22163439

A hybrid MAC protocol design for energy-efficient very-high-throughput millimeter wave, wireless sensor communication networks

NASA Astrophysics Data System (ADS)

Jian, Wei; Estevez, Claudio; Chowdhury, Arshad; Jia, Zhensheng; Wang, Jianxin; Yu, Jianguo; Chang, Gee-Kung

2010-12-01

This paper presents an energy-efficient Medium Access Control (MAC) protocol for very-high-throughput millimeter-wave (mm-wave) wireless sensor communication networks (VHT-MSCNs) based on hybrid multiple access techniques of frequency division multiplexing access (FDMA) and time division multiplexing access (TDMA). An energy-efficient Superframe for wireless sensor communication network employing directional mm-wave wireless access technologies is proposed for systems that require very high throughput, such as high definition video signals, for sensing, processing, transmitting, and actuating functions. Energy consumption modeling for each network element and comparisons among various multi-access technologies in term of power and MAC layer operations are investigated for evaluating the energy-efficient improvement of proposed MAC protocol.

A MAC Protocol for Medical Monitoring Applications of Wireless Body Area Networks

PubMed Central

Shu, Minglei; Yuan, Dongfeng; Zhang, Chongqing; Wang, Yinglong; Chen, Changfang

2015-01-01

Targeting the medical monitoring applications of wireless body area networks (WBANs), a hybrid medium access control protocol using an interrupt mechanism (I-MAC) is proposed to improve the energy and time slot utilization efficiency and to meet the data delivery delay requirement at the same time. Unlike existing hybrid MAC protocols, a superframe structure with a longer length is adopted to avoid unnecessary beacons. The time slots are mostly allocated to nodes with periodic data sources. Short interruption slots are inserted into the superframe to convey the urgent data and to guarantee the real-time requirements of these data. During these interruption slots, the coordinator can break the running superframe and start a new superframe. A contention access period (CAP) is only activated when there are more data that need to be delivered. Experimental results show the effectiveness of the proposed MAC protocol in WBANs with low urgent traffic. PMID:26046596

The cognitive based approach of capacity assessment in psychiatry: a philosophical critique of the MacCAT-T.

PubMed

Breden, Torsten Marcus; Vollmann, Jochen

2004-12-01

This article gives a brief introduction to the MacArthur Competence Assessment Tool-Treatment (MacCAT-T) and critically examines its theoretical presuppositions. On the basis of empirical, methodological and ethical critique it is emphasised that the cognitive bias that underlies the MacCAT-T assessment needs to be modified. On the one hand it has to be admitted that the operationalisation of competence in terms of value-free categories, e.g. rational decision abilities, guarantees objectivity to a great extent; but on the other hand it bears severe problems. Firstly, the cognitive focus is in itself a normative convention in the process of anthropological value-attribution. Secondly, it misses the complexity of the decision process in real life. It is therefore suggested that values, emotions and other biographic and context specific aspects should be considered when interpreting the cognitive standards according to the MacArthur model. To fill the gap between cognitive and non-cognitive approaches the phenomenological theory of personal constructs is briefly introduced. In conclusion some main demands for further research to develop a multi-step model of competence assessment are outlined.

An Efficient and QoS Supported Multichannel MAC Protocol for Vehicular Ad Hoc Networks

PubMed Central

Tan, Guozhen; Yu, Chao

2017-01-01

Vehicular Ad Hoc Networks (VANETs) employ multichannel to provide a variety of safety and non-safety (transport efficiency and infotainment) applications, based on the IEEE 802.11p and IEEE 1609.4 protocols. Different types of applications require different levels Quality-of-Service (QoS) support. Recently, transport efficiency and infotainment applications (e.g., electronic map download and Internet access) have received more and more attention, and this kind of applications is expected to become a big market driver in a near future. In this paper, we propose an Efficient and QoS supported Multichannel Medium Access Control (EQM-MAC) protocol for VANETs in a highway environment. The EQM-MAC protocol utilizes the service channel resources for non-safety message transmissions during the whole synchronization interval, and it dynamically adjusts minimum contention window size for different non-safety services according to the traffic conditions. Theoretical model analysis and extensive simulation results show that the EQM-MAC protocol can support QoS services, while ensuring the high saturation throughput and low transmission delay for non-safety applications. PMID:28991217

An Adaptive OFDMA-Based MAC Protocol for Underwater Acoustic Wireless Sensor Networks

PubMed Central

Khalil, Issa M.; Gadallah, Yasser; Hayajneh, Mohammad; Khreishah, Abdallah

2012-01-01

Underwater acoustic wireless sensor networks (UAWSNs) have many applications across various civilian and military domains. However, they suffer from the limited available bandwidth of acoustic signals and harsh underwater conditions. In this work, we present an Orthogonal Frequency Division Multiple Access (OFDMA)-based Media Access Control (MAC) protocol that is configurable to suit the operating requirements of the underwater sensor network. The protocol has three modes of operation, namely random, equal opportunity and energy-conscious modes of operation. Our MAC design approach exploits the multi-path characteristics of a fading acoustic channel to convert it into parallel independent acoustic sub-channels that undergo flat fading. Communication between node pairs within the network is done using subsets of these sub-channels, depending on the configurations of the active mode of operation. Thus, the available limited bandwidth gets fully utilized while completely avoiding interference. We derive the mathematical model for optimal power loading and subcarrier selection, which is used as basis for all modes of operation of the protocol. We also conduct many simulation experiments to evaluate and compare our protocol with other Code Division Multiple Access (CDMA)-based MAC protocols. PMID:23012517

An adaptive OFDMA-based MAC protocol for underwater acoustic wireless sensor networks.

PubMed

Khalil, Issa M; Gadallah, Yasser; Hayajneh, Mohammad; Khreishah, Abdallah

2012-01-01

Underwater acoustic wireless sensor networks (UAWSNs) have many applications across various civilian and military domains. However, they suffer from the limited available bandwidth of acoustic signals and harsh underwater conditions. In this work, we present an Orthogonal Frequency Division Multiple Access (OFDMA)-based Media Access Control (MAC) protocol that is configurable to suit the operating requirements of the underwater sensor network. The protocol has three modes of operation, namely random, equal opportunity and energy-conscious modes of operation. Our MAC design approach exploits the multi-path characteristics of a fading acoustic channel to convert it into parallel independent acoustic sub-channels that undergo flat fading. Communication between node pairs within the network is done using subsets of these sub-channels, depending on the configurations of the active mode of operation. Thus, the available limited bandwidth gets fully utilized while completely avoiding interference. We derive the mathematical model for optimal power loading and subcarrier selection, which is used as basis for all modes of operation of the protocol. We also conduct many simulation experiments to evaluate and compare our protocol with other Code Division Multiple Access (CDMA)-based MAC protocols.

Industrial WSN Based on IR-UWB and a Low-Latency MAC Protocol

NASA Astrophysics Data System (ADS)

Reinhold, Rafael; Underberg, Lisa; Wulf, Armin; Kays, Ruediger

2016-07-01

Wireless sensor networks for industrial communication require high reliability and low latency. As current wireless sensor networks do not entirely meet these requirements, novel system approaches need to be developed. Since ultra wideband communication systems seem to be a promising approach, this paper evaluates the performance of the IEEE 802.15.4 impulse-radio ultra-wideband physical layer and the IEEE 802.15.4 Low Latency Deterministic Network (LLDN) MAC for industrial applications. Novel approaches and system adaptions are proposed to meet the application requirements. In this regard, a synchronization approach based on circular average magnitude difference functions (CAMDF) and on a clean template (CT) is presented for the correlation receiver. An adapted MAC protocol titled aggregated low latency (ALL) MAC is proposed to significantly reduce the resulting latency. Based on the system proposals, a hardware prototype has been developed, which proves the feasibility of the system and visualizes the real-time performance of the MAC protocol.

BFT replication resistant to MAC attacks

NASA Astrophysics Data System (ADS)

Zbierski, Maciej

2016-09-01

Over the last decade numerous Byzantine fault-tolerant (BFT) replication protocols have been proposed in the literature. However, the vast majority of these solutions reuse the same authentication scheme, which makes them susceptible to a so called MAC attack. Such vulnerability enables malicious clients to undetectably prevent the replicated service from processing incoming client requests, and consequently making it permanently unavailable. While some BFT protocols attempted to address this issue by using different authentication mechanisms, they at the same time significantly degraded the performance achieved in correct environments. This article presents a novel adaptive authentication mechanism which can be combined with practically any Byzantine fault-tolerant replication protocol. Unlike previous solutions, the proposed scheme dynamically switches between two operation modes to combine high performance in correct environments and liveness during MAC attacks. The experiment results presented in the article demonstrate that the proposed mechanism can sufficiently tolerate MAC attacks without introducing any observable overhead whenever no faults are present.

McMAC: Towards a MAC Protocol with Multi-Constrained QoS Provisioning for Diverse Traffic in Wireless Body Area Networks

PubMed Central

Monowar, Muhammad Mostafa; Hassan, Mohammad Mehedi; Bajaber, Fuad; Al-Hussein, Musaed; Alamri, Atif

2012-01-01

The emergence of heterogeneous applications with diverse requirements for resource-constrained Wireless Body Area Networks (WBANs) poses significant challenges for provisioning Quality of Service (QoS) with multi-constraints (delay and reliability) while preserving energy efficiency. To address such challenges, this paper proposes McMAC, a MAC protocol with multi-constrained QoS provisioning for diverse traffic classes in WBANs. McMAC classifies traffic based on their multi-constrained QoS demands and introduces a novel superframe structure based on the “transmit-whenever-appropriate” principle, which allows diverse periods for diverse traffic classes according to their respective QoS requirements. Furthermore, a novel emergency packet handling mechanism is proposed to ensure packet delivery with the least possible delay and the highest reliability. McMAC is also modeled analytically, and extensive simulations were performed to evaluate its performance. The results reveal that McMAC achieves the desired delay and reliability guarantee according to the requirements of a particular traffic class while achieving energy efficiency. PMID:23202224

High-Bandwidth Tactical-Network Data Analysis in a High-Performance-Computing (HPC) Environment: Transport Protocol (Transmission Control Protocol/User Datagram Protocol [TCP/UDP]) Analysis

DTIC Science & Technology

2015-09-01

the network Mac8 Medium Access Control ( Mac ) (Ethernet) address observed as destination for outgoing packets subsessionid8 Zero-based index of...15. SUBJECT TERMS tactical networks, data reduction, high-performance computing, data analysis, big data 16. SECURITY CLASSIFICATION OF: 17...Integer index of row cts_deid Device (instrument) Identifier where observation took place cts_collpt Collection point or logical observation point on

Performance Analysis of IEEE 802.15.3 MAC Protocol with Different ACK Polices

NASA Astrophysics Data System (ADS)

Mehta, S.; Kwak, K. S.

The wireless personal area network (WPAN) is an emerging wireless technology for future short range indoor and outdoor communication applications. The IEEE 802.15.3 medium access control (MAC) is proposed, specially, for short range high data rates applications, to coordinate the access to the wireless medium among the competing devices. This paper uses analytical model to study the performance analysis of WPAN (IEEE 802.15.3) MAC in terms of throughput, efficient bandwidth utilization, and delay with various acknowledgment schemes under different parameters. Also, some important observations are obtained, which can be very useful to the protocol architectures. Finally, we come up with some important research issues to further investigate the possible improvements in the WPAN MAC.

Intelligent Cooperative MAC Protocol for Balancing Energy Consumption

NASA Astrophysics Data System (ADS)

Wu, S.; Liu, K.; Huang, B.; Liu, F.

To extend the lifetime of wireless sensor networks, we proposed an intelligent balanced energy consumption cooperative MAC protocol (IBEC-CMAC) based on the multi-node cooperative transmission model. The protocol has priority to access high-quality channels for reducing energy consumption of each transmission. It can also balance the energy consumption among cooperative nodes by using high residual energy nodes instead of excessively consuming some node's energy. Simulation results show that IBEC-CMAC can obtain longer network lifetime and higher energy utilization than direct transmission.

Modular Energy-Efficient and Robust Paradigms for a Disaster-Recovery Process over Wireless Sensor Networks

PubMed Central

Razaque, Abdul; Elleithy, Khaled

2015-01-01

Robust paradigms are a necessity, particularly for emerging wireless sensor network (WSN) applications. The lack of robust and efficient paradigms causes a reduction in the provision of quality of service (QoS) and additional energy consumption. In this paper, we introduce modular energy-efficient and robust paradigms that involve two archetypes: (1) the operational medium access control (O-MAC) hybrid protocol and (2) the pheromone termite (PT) model. The O-MAC protocol controls overhearing and congestion and increases the throughput, reduces the latency and extends the network lifetime. O-MAC uses an optimized data frame format that reduces the channel access time and provides faster data delivery over the medium. Furthermore, O-MAC uses a novel randomization function that avoids channel collisions. The PT model provides robust routing for single and multiple links and includes two new significant features: (1) determining the packet generation rate to avoid congestion and (2) pheromone sensitivity to determine the link capacity prior to sending the packets on each link. The state-of-the-art research in this work is based on improving both the QoS and energy efficiency. To determine the strength of O-MAC with the PT model; we have generated and simulated a disaster recovery scenario using a network simulator (ns-3.10) that monitors the activities of disaster recovery staff; hospital staff and disaster victims brought into the hospital. Moreover; the proposed paradigm can be used for general purpose applications. Finally; the QoS metrics of the O-MAC and PT paradigms are evaluated and compared with other known hybrid protocols involving the MAC and routing features. The simulation results indicate that O-MAC with PT produced better outcomes. PMID:26153768

Modular Energy-Efficient and Robust Paradigms for a Disaster-Recovery Process over Wireless Sensor Networks.

PubMed

Razaque, Abdul; Elleithy, Khaled

2015-07-06

Robust paradigms are a necessity, particularly for emerging wireless sensor network (WSN) applications. The lack of robust and efficient paradigms causes a reduction in the provision of quality of service (QoS) and additional energy consumption. In this paper, we introduce modular energy-efficient and robust paradigms that involve two archetypes: (1) the operational medium access control (O-MAC) hybrid protocol and (2) the pheromone termite (PT) model. The O-MAC protocol controls overhearing and congestion and increases the throughput, reduces the latency and extends the network lifetime. O-MAC uses an optimized data frame format that reduces the channel access time and provides faster data delivery over the medium. Furthermore, O-MAC uses a novel randomization function that avoids channel collisions. The PT model provides robust routing for single and multiple links and includes two new significant features: (1) determining the packet generation rate to avoid congestion and (2) pheromone sensitivity to determine the link capacity prior to sending the packets on each link. The state-of-the-art research in this work is based on improving both the QoS and energy efficiency. To determine the strength of O-MAC with the PT model; we have generated and simulated a disaster recovery scenario using a network simulator (ns-3.10) that monitors the activities of disaster recovery staff; hospital staff and disaster victims brought into the hospital. Moreover; the proposed paradigm can be used for general purpose applications. Finally; the QoS metrics of the O-MAC and PT paradigms are evaluated and compared with other known hybrid protocols involving the MAC and routing features. The simulation results indicate that O-MAC with PT produced better outcomes.

CoR-MAC: Contention over Reservation MAC Protocol for Time-Critical Services in Wireless Body Area Sensor Networks

PubMed Central

Yu, Jeongseok; Park, Laihyuk; Park, Junho; Cho, Sungrae; Keum, Changsup

2016-01-01

Reserving time slots for urgent data, such as life-critical information, seems to be very attractive to guarantee their deadline requirements in wireless body area sensor networks (WBASNs). On the other hand, this reservation imposes a negative impact on performance for the utilization of a channel. This paper proposes a new channel access scheme referred to as the contention over reservation MAC (CoR-MAC) protocol for time-critical services in wireless body area sensor networks. CoR-MAC uses the dual reservation; if the reserved time slots are known to be vacant, other nodes can access the time slots by contention-based reservation to maximize the utilization of a channel and decrease the delay of the data. To measure the effectiveness of the proposed scheme against IEEE 802.15.4 and IEEE 802.15.6, we evaluated their performances with various performance indexes. The CoR-MAC showed 50% to 850% performance improvement in terms of the delay of urgent and time-critical data according to the number of nodes. PMID:27171085

A Hybrid Lifetime Extended Directional Approach for WBANs

PubMed Central

Li, Changle; Yuan, Xiaoming; Yang, Li; Song, Yueyang

2015-01-01

Wireless Body Area Networks (WBANs) can provide real-time and reliable health monitoring, attributing to the human-centered and sensor interoperability properties. WBANs have become a key component of the ubiquitous eHealth (electronic health) revolution that prospers on the basis of information and communication technologies. The prime consideration in WBAN is how to maximize the network lifetime with battery-powered sensor nodes in energy constraint. Novel solutions in Medium Access Control (MAC) protocols are imperative to satisfy the particular BAN scenario and the need of excellent energy efficiency in healthcare applications. In this paper, we propose a hybrid Lifetime Extended Directional Approach (LEDA) MAC protocol based on IEEE 802.15.6 to reduce energy consumption and prolong network lifetime. The LEDA MAC protocol takes full advantages of directional superiority in energy saving that employs multi-beam directional mode in Carrier Sense Multiple Access/Collision Avoidance (CSMA/CA) and single-beam directional mode in Time Division Multiple Access (TDMA) for alternative in data reservation and transmission according to the traffic varieties. Moreover, the impacts of some inherent problems of directional antennas such as deafness and hidden terminal problem can be decreased owing to that all nodes generate individual beam according to user priorities designated. Furthermore, LEDA MAC employs a Dynamic Polled Allocation Period (DPAP) for burst data transmissions to increase the network reliability and adaptability. Extensive analysis and simulation results show that the proposed LEDA MAC protocol achieves extended network lifetime with improved performance compared with IEEE 802.15.6. PMID:26556357

An Energy Efficient MAC Protocol for Multi-Hop Swallowable Body Sensor Networks

PubMed Central

Lin, Lin; Yang, Chengfeng; Wong, Kai Juan; Yan, Hao; Shen, Junwen; Phee, Soo Jay

2014-01-01

Swallowable body sensor networks (BSNs) are composed of sensors which are swallowed by patients and send the collected data to the outside coordinator. These sensors are energy constraint and the batteries are difficult to be replaced. The medium access control (MAC) protocol plays an important role in energy management. This paper investigates an energy efficient MAC protocol design for swallowable BSNs. Multi-hop communication is analyzed and proved more energy efficient than single-hop communication within the human body when the circuitry power is low. Based on this result, a centrally controlled time slotting schedule is proposed. The major workload is shifted from the sensors to the coordinator. The coordinator collects the path-loss map and calculates the schedules, including routing, slot assignment and transmission power. Sensor nodes follow the schedules to send data in a multi-hop way. The proposed protocol is compared with the IEEE 802.15.6 protocol in terms of energy consumption. The results show that it is more energy efficient than IEEE 802.15.6 for swallowable BSN scenarios. PMID:25330049

An FEC Adaptive Multicast MAC Protocol for Providing Reliability in WLANs

NASA Astrophysics Data System (ADS)

Basalamah, Anas; Sato, Takuro

For wireless multicast applications like multimedia conferencing, voice over IP and video/audio streaming, a reliable transmission of packets within short delivery delay is needed. Moreover, reliability is crucial to the performance of error intolerant applications like file transfer, distributed computing, chat and whiteboard sharing. Forward Error Correction (FEC) is frequently used in wireless multicast to enhance Packet Error Rate (PER) performance, but cannot assure full reliability unless coupled with Automatic Repeat Request forming what is knows as Hybrid-ARQ. While reliable FEC can be deployed at different levels of the protocol stack, it cannot be deployed on the MAC layer of the unreliable IEEE802.11 WLAN due to its inability to exchange ACKs with multiple recipients. In this paper, we propose a Multicast MAC protocol that enhances WLAN reliability by using Adaptive FEC and study it's performance through mathematical analysis and simulation. Our results show that our protocol can deliver high reliability and throughput performance.

Treatment Decision-Making Capacity in Children and Adolescents Hospitalized for an Acute Mental Disorder: The Role of Cognitive Functioning and Psychiatric Symptoms.

PubMed

Mandarelli, Gabriele; Sabatello, Ugo; Lapponi, Elisa; Pace, Giulia; Ferrara, Mauro; Ferracuti, Stefano

2017-06-01

This study was conducted to assess treatment decision-making capacity (TDMC) in a child and adolescent psychiatric sample and to verify possible associations between TDMC, psychiatric symptom severity, and cognitive functioning. Twenty-two consecutively recruited patients hospitalized for an acute mental disorder, aged 11-18 years, underwent measurement of TDMC by the MacArthur Competence Assessment Tool for Treatment (MacCAT-T). The MacCAT-T interview focused on patients' current treatment, which comprised second-generation antipsychotics (45.5%), first-generation antipsychotics (13.6%), antiepileptic drugs used as mood stabilizers or lithium carbonate (45.5%), selective serotonin reuptake inhibitors (32%), and benzodiazepines (18%). We moreover measured cognitive functioning (Wechsler Intelligence Scale for Children III) and psychiatric symptom severity (Brief Psychiatric Rating Scale v 4.0). Patients' TDMC varied within the sample, but MacCAT-T scores were good in the sample overall, suggesting that children and adolescents with severe mental disorders could be competent to consent to treatment. The TDMC proved independent of psychiatric diagnosis while being positively associated with cognitive functioning and negatively with excitement. The MacCAT-T proved feasible for measuring TDMC in a child and adolescent psychiatric sample. TDMC in minors with severe mental disorders was not necessarily impaired. These results deserve reconsidering the interplay between minors and surrogate decision-makers as concerning treatment decisions.

IDMA-Based MAC Protocol for Satellite Networks with Consideration on Channel Quality

PubMed Central

2014-01-01

In order to overcome the shortcomings of existing medium access control (MAC) protocols based on TDMA or CDMA in satellite networks, interleave division multiple access (IDMA) technique is introduced into satellite communication networks. Therefore, a novel wide-band IDMA MAC protocol based on channel quality is proposed in this paper, consisting of a dynamic power allocation algorithm, a rate adaptation algorithm, and a call admission control (CAC) scheme. Firstly, the power allocation algorithm combining the technique of IDMA SINR-evolution and channel quality prediction is developed to guarantee high power efficiency even in terrible channel conditions. Secondly, the effective rate adaptation algorithm, based on accurate channel information per timeslot and by the means of rate degradation, can be realized. What is more, based on channel quality prediction, the CAC scheme, combining the new power allocation algorithm, rate scheduling, and buffering strategies together, is proposed for the emerging IDMA systems, which can support a variety of traffic types, and offering quality of service (QoS) requirements corresponding to different priority levels. Simulation results show that the new wide-band IDMA MAC protocol can make accurate estimation of available resource considering the effect of multiuser detection (MUD) and QoS requirements of multimedia traffic, leading to low outage probability as well as high overall system throughput. PMID:25126592

An energy-efficient rate adaptive media access protocol (RA-MAC) for long-lived sensor networks.

PubMed

Hu, Wen; Chen, Quanjun; Corke, Peter; O'Rourke, Damien

2010-01-01

We introduce an energy-efficient Rate Adaptive Media Access Control (RA-MAC) algorithm for long-lived Wireless Sensor Networks (WSNs). Previous research shows that the dynamic and lossy nature of wireless communications is one of the major challenges to reliable data delivery in WSNs. RA-MAC achieves high link reliability in such situations by dynamically trading off data rate for channel gain. The extra gain that can be achieved reduces the packet loss rate which contributes to reduced energy expenditure through a reduced numbers of retransmissions. We achieve this at the expense of raw bit rate which generally far exceeds the application's link requirement. To minimize communication energy consumption, RA-MAC selects the optimal data rate based on the estimated link quality at each data rate and an analytical model of the energy consumption. Our model shows how the selected data rate depends on different channel conditions in order to minimize energy consumption. We have implemented RA-MAC in TinyOS for an off-the-shelf sensor platform (the TinyNode) on top of a state-of-the-art WSN Media Access Control Protocol, SCP-MAC, and evaluated its performance by comparing our implementation with the original SCP-MAC using both simulation and experiment.

Software-Defined Architectures for Spectrally Efficient Cognitive Networking in Extreme Environments

NASA Astrophysics Data System (ADS)

Sklivanitis, Georgios

The objective of this dissertation is the design, development, and experimental evaluation of novel algorithms and reconfigurable radio architectures for spectrally efficient cognitive networking in terrestrial, airborne, and underwater environments. Next-generation wireless communication architectures and networking protocols that maximize spectrum utilization efficiency in congested/contested or low-spectral availability (extreme) communication environments can enable a rich body of applications with unprecedented societal impact. In recent years, underwater wireless networks have attracted significant attention for military and commercial applications including oceanographic data collection, disaster prevention, tactical surveillance, offshore exploration, and pollution monitoring. Unmanned aerial systems that are autonomously networked and fully mobile can assist humans in extreme or difficult-to-reach environments and provide cost-effective wireless connectivity for devices without infrastructure coverage. Cognitive radio (CR) has emerged as a promising technology to maximize spectral efficiency in dynamically changing communication environments by adaptively reconfiguring radio communication parameters. At the same time, the fast developing technology of software-defined radio (SDR) platforms has enabled hardware realization of cognitive radio algorithms for opportunistic spectrum access. However, existing algorithmic designs and protocols for shared spectrum access do not effectively capture the interdependencies between radio parameters at the physical (PHY), medium-access control (MAC), and network (NET) layers of the network protocol stack. In addition, existing off-the-shelf radio platforms and SDR programmable architectures are far from fulfilling runtime adaptation and reconfiguration across PHY, MAC, and NET layers. Spectrum allocation in cognitive networks with multi-hop communication requirements depends on the location, network traffic load, and interference profile at each network node. As a result, the development and implementation of algorithms and cross-layer reconfigurable radio platforms that can jointly treat space, time, and frequency as a unified resource to be dynamically optimized according to inter- and intra-network interference constraints is of fundamental importance. In the next chapters, we present novel algorithmic and software/hardware implementation developments toward the deployment of spectrally efficient terrestrial, airborne, and underwater wireless networks. In Chapter 1 we review the state-of-art in commercially available SDR platforms, describe their software and hardware capabilities, and classify them based on their ability to enable rapid prototyping and advance experimental research in wireless networks. Chapter 2 discusses system design and implementation details toward real-time evaluation of a software-radio platform for all-spectrum cognitive channelization in the presence of narrowband or wideband primary stations. All-spectrum channelization is achieved by designing maximum signal-to-interference-plus-noise ratio (SINR) waveforms that span the whole continuum of the device-accessible spectrum, while satisfying peak power and interference temperature (IT) constraints for the secondary and primary users, respectively. In Chapter 3, we introduce the concept of all-spectrum channelization based on max-SINR optimized sparse-binary waveforms, we propose optimal and suboptimal waveform design algorithms, and evaluate their SINR and bit-error-rate (BER) performance in an SDR testbed. Chapter 4 considers the problem of channel estimation with minimal pilot signaling in multi-cell multi-user multi-input multi-output (MIMO) systems with very large antenna arrays at the base station, and proposes a least-squares (LS)-type algorithm that iteratively extracts channel and data estimates from a short record of data measurements. Our algorithmic developments toward spectrally-efficient cognitive networking through joint optimization of channel access code-waveforms and routes in a multi-hop network are described in Chapter 5. Algorithmic designs are software optimized on heterogeneous multi-core general-purpose processor (GPP)-based SDR architectures by leveraging a novel software-radio framework that offers self-optimization and real-time adaptation capabilities at the PHY, MAC, and NET layers of the network protocol stack. Our system design approach is experimentally validated under realistic conditions in a large-scale hybrid ground-air testbed deployment. Chapter 6 reviews the state-of-art in software and hardware platforms for underwater wireless networking and proposes a software-defined acoustic modem prototype that enables (i) cognitive reconfiguration of PHY/MAC parameters, and (ii) cross-technology communication adaptation. The proposed modem design is evaluated in terms of effective communication data rate in both water tank and lake testbed setups. In Chapter 7, we present a novel receiver configuration for code-waveform-based multiple-access underwater communications. The proposed receiver is fully reconfigurable and executes (i) all-spectrum cognitive channelization, and (ii) combined synchronization, channel estimation, and demodulation. Experimental evaluation in terms of SINR and BER show that all-spectrum channelization is a powerful proposition for underwater communications. At the same time, the proposed receiver design can significantly enhance bandwidth utilization. Finally, in Chapter 8, we focus on challenging practical issues that arise in underwater acoustic sensor network setups where co-located multi-antenna sensor deployment is not feasible due to power, computation, and hardware limitations, and design, implement, and evaluate an underwater receiver structure that accounts for multiple carrier frequency and timing offsets in virtual (distributed) MIMO underwater systems.

Internet-based cognitive behavior therapy for major depressive disorder: A randomized controlled trial.

PubMed

Rosso, Isabelle M; Killgore, William D S; Olson, Elizabeth A; Webb, Christian A; Fukunaga, Rena; Auerbach, Randy P; Gogel, Hannah; Buchholz, Jennifer L; Rauch, Scott L

2017-03-01

Prior research has shown that the Sadness Program, a technician-assisted Internet-based cognitive behavioral therapy (iCBT) intervention developed in Australia, is effective for treating major depressive disorder (MDD). The current study aimed to expand this work by adapting the protocol for an American population and testing the Sadness Program with an attention control group. In this parallel-group, randomized controlled trial, adult MDD participants (18-45 years) were randomized to a 10-week period of iCBT (n = 37) or monitored attention control (MAC; n = 40). Participants in the iCBT group completed six online therapy lessons, which included access to content summaries and homework assignments. During the 10-week trial, iCBT and MAC participants logged into the web-based system six times to complete self-report symptom scales, and a nonclinician technician contacted participants weekly to provide encouragement and support. The primary outcome was the Hamilton Rating Scale for Depression (HRSD), and the secondary outcomes were the Patient Health Questionnaire-9 and Kessler-10. Intent-to-treat analyses revealed significantly greater reductions in depressive symptoms in iCBT compared with MAC participants, using both the self-report measures and the clinician-rated HRSD (d = -0.80). Importantly, iCBT participants also showed significantly higher rates of clinical response and remission. Exploratory analyses did not support illness severity as a moderator of treatment outcome. The Sadness Program led to significant reductions in depression and distress symptoms. With its potential to be delivered in a scalable, cost-efficient manner, iCBT is a promising strategy to enhance access to effective care. © 2016 Wiley Periodicals, Inc.

Medium Access Control for Opportunistic Concurrent Transmissions under Shadowing Channels

PubMed Central

Son, In Keun; Mao, Shiwen; Hur, Seung Min

2009-01-01

We study the problem of how to alleviate the exposed terminal effect in multi-hop wireless networks in the presence of log-normal shadowing channels. Assuming node location information, we propose an extension of the IEEE 802.11 MAC protocol that sched-ules concurrent transmissions in the presence of log-normal shadowing, thus mitigating the exposed terminal problem and improving network throughput and delay performance. We observe considerable improvements in throughput and delay achieved over the IEEE 802.11 MAC under various network topologies and channel conditions in ns-2 simulations, which justify the importance of considering channel randomness in MAC protocol design for multi-hop wireless networks. PMID:22408556

Performance and analysis of MAC protocols based on application

NASA Astrophysics Data System (ADS)

Yadav, Ravi; Daniel, A. K.

2018-04-01

Wireless Sensor Network is one of the rapid emerging technology in recent decades. It covers large application area as civilian and military. Wireless Sensor Network primary consists of sensor nodes having low-power, low cost and multifunctional activities to collaborates and communicates via wireless medium. The deployment of sensor nodes are adhoc in nature, so sensor nodes are auto organize themselves in such a way to communicate with each other. The characteristics make more challenging areas on WSNs. This paper gives overview about characteristics of WSNs, Architecture and Contention Based MAC protocol. The paper present analysis of various protocol based on performance.

Treatment Decision-Making Capacity in Children and Adolescents Hospitalized for an Acute Mental Disorder: The Role of Cognitive Functioning and Psychiatric Symptoms

PubMed Central

Sabatello, Ugo; Lapponi, Elisa; Pace, Giulia; Ferrara, Mauro; Ferracuti, Stefano

2017-01-01

Abstract Objective: This study was conducted to assess treatment decision-making capacity (TDMC) in a child and adolescent psychiatric sample and to verify possible associations between TDMC, psychiatric symptom severity, and cognitive functioning. Methods: Twenty-two consecutively recruited patients hospitalized for an acute mental disorder, aged 11–18 years, underwent measurement of TDMC by the MacArthur Competence Assessment Tool for Treatment (MacCAT-T). The MacCAT-T interview focused on patients' current treatment, which comprised second-generation antipsychotics (45.5%), first-generation antipsychotics (13.6%), antiepileptic drugs used as mood stabilizers or lithium carbonate (45.5%), selective serotonin reuptake inhibitors (32%), and benzodiazepines (18%). We moreover measured cognitive functioning (Wechsler Intelligence Scale for Children III) and psychiatric symptom severity (Brief Psychiatric Rating Scale v 4.0). Results: Patients' TDMC varied within the sample, but MacCAT-T scores were good in the sample overall, suggesting that children and adolescents with severe mental disorders could be competent to consent to treatment. The TDMC proved independent of psychiatric diagnosis while being positively associated with cognitive functioning and negatively with excitement. Conclusion: The MacCAT-T proved feasible for measuring TDMC in a child and adolescent psychiatric sample. TDMC in minors with severe mental disorders was not necessarily impaired. These results deserve reconsidering the interplay between minors and surrogate decision-makers as concerning treatment decisions. PMID:27935747

Intelligent Local Avoided Collision (iLAC) MAC Protocol for Very High Speed Wireless Network

NASA Astrophysics Data System (ADS)

Hieu, Dinh Chi; Masuda, Akeo; Rabarijaona, Verotiana Hanitriniala; Shimamoto, Shigeru

Future wireless communication systems aim at very high data rates. As the medium access control (MAC) protocol plays the central role in determining the overall performance of the wireless system, designing a suitable MAC protocol is critical to fully exploit the benefit of high speed transmission that the physical layer (PHY) offers. In the latest 802.11n standard [2], the problem of long overhead has been addressed adequately but the issue of excessive colliding transmissions, especially in congested situation, remains untouched. The procedure of setting the backoff value is the heart of the 802.11 distributed coordination function (DCF) to avoid collision in which each station makes its own decision on how to avoid collision in the next transmission. However, collision avoidance is a problem that can not be solved by a single station. In this paper, we introduce a new MAC protocol called Intelligent Local Avoided Collision (iLAC) that redefines individual rationality in choosing the backoff counter value to avoid a colliding transmission. The distinguishing feature of iLAC is that it fundamentally changes this decision making process from collision avoidance to collaborative collision prevention. As a result, stations can avoid colliding transmissions with much greater precision. Analytical solution confirms the validity of this proposal and simulation results show that the proposed algorithm outperforms the conventional algorithms by a large margin.

[Study protocol of a prevention of recurrent suicidal behaviour program based on case management (PSyMAC)].

PubMed

Sáiz, Pilar A; Rodríguez-Revuelta, Julia; González-Blanco, Leticia; Burón, Patricia; Al-Halabí, Susana; Garrido, Marlen; García-Alvarez, Leticia; García-Portilla, Paz; Bobes, Julio

2014-01-01

Prevention of suicidal behaviour is a public health priority in the European Union. A previous suicide attempt is the best risk predictor for future attempts, as well as completed suicides. The primary aim of this article is to describe a controlled study protocol designed for prevention of recurrent suicidal behaviour that proposes case management, and includes a psychoeducation program, as compared with the standard intervention (PSyMAC). Patients admitted from January 2011 to June 2013 to the emergency room of the Hospital Universitario Central de Asturias were evaluated using a protocol including sociodemographic, psychiatric, and psychosocial assessment. Patients were randomly assigned to either a group receiving continuous case management including participation in a psychoeducation program (experimental group), or a control group receiving standard care. The primary objective is to examine whether or not the period of time until recurrent suicidal behaviour in the experimental group is significantly different from that of the control group. PSyMAC proposes low cost and easily adaptable interventions to the usual clinical setting that can help to compensate the shortcoming of specific action protocols and suicidal behaviour prevention programs in our country. The evaluation of PSyMAC results will determine their real effectivity as a case-magament program to reduce suicidal risk. Copyright © 2013 SEP y SEPB. Published by Elsevier España. All rights reserved.

Strategies for Optimal MAC Parameters Tuning in IEEE 802.15.6 Wearable Wireless Sensor Networks.

PubMed

Alam, Muhammad Mahtab; Ben Hamida, Elyes

2015-09-01

Wireless body area networks (WBAN) has penetrated immensely in revolutionizing the classical heath-care system. Recently, number of WBAN applications has emerged which introduce potential limits to existing solutions. In particular, IEEE 802.15.6 standard has provided great flexibility, provisions and capabilities to deal emerging applications. In this paper, we investigate the application-specific throughput analysis by fine-tuning the physical (PHY) and medium access control (MAC) parameters of the IEEE 802.15.6 standard. Based on PHY characterizations in narrow band, at the MAC layer, carrier sense multiple access collision avoidance (CSMA/CA) and scheduled access protocols are extensively analyzed. It is concluded that, IEEE 802.15.6 standard can satisfy most of the WBANs applications throughput requirements by maximum achieving 680 Kbps. However, those emerging applications which require high quality audio or video transmissions, standard is not able to meet their constraints. Moreover, delay, energy efficiency and successful packet reception are considered as key performance metrics for comparing the MAC protocols. CSMA/CA protocol provides the best results to meet the delay constraints of medical and non-medical WBAN applications. Whereas, the scheduled access approach, performs very well both in energy efficiency and packet reception ratio.

Multimedia Consent for Research in People With Schizophrenia and Normal Subjects: a Randomized Controlled Trial

PubMed Central

Jeste, Dilip V.; Palmer, Barton W.; Golshan, Shahrokh; Eyler, Lisa T.; Dunn, Laura B.; Meeks, Thomas; Glorioso, Danielle; Fellows, Ian; Kraemer, Helena; Appelbaum, Paul S.

2009-01-01

Limitations of printed, text-based, consent forms have long been documented and may be particularly problematic for persons at risk for impaired decision-making capacity, such as those with schizophrenia. We conducted a randomized controlled comparison of the effectiveness of a multimedia vs routine consent procedure (augmented with a 10-minute control video presentation) as a means of enhancing comprehension among 128 middle-aged and older persons with schizophrenia and 60 healthy comparison subjects. The primary outcome measure was manifest decisional capacity (understanding, appreciation, reasoning, and expression of choice) for participation in a (hypothetical) clinical drug trial, as measured with the MacArthur Competence Assessment Tool for Clinical Research (MacCAT-CR) and the University of California San Diego (UCSD) Brief Assessment for Capacity to Consent (UBACC). The MacCAT-CR and UBACC were administered by research assistants kept blind to consent condition. Additional assessments included standardized measures of psychopathology and cognitive functioning. Relative to patients in the routine consent condition, schizophrenia patients receiving multimedia consent had significantly better scores on the UBACC and on the MacCAT-CR understanding and expression of choice subscales and were significantly more likely to be categorized as being capable to consent than those in the routine consent condition (as categorized with several previously established criteria). Among the healthy subjects, there were few significant effects of consent condition. These findings suggest that multimedia consent procedures may be a valuable consent aid that should be considered for use when enrolling participants at risk for impaired decisional capacity, particularly for complex and/or high-risk research protocols. PMID:18245061

An Application of MacLaury's Vantage Theory to Abstract Categories: Identity and the Process of Categorisation

ERIC Educational Resources Information Center

Fabiszak, Malgorzata

2010-01-01

This paper is an application of Robert E. MacLaury's Vantage Theory (VT) to the analysis of real life spoken discourse. It utilizes Dennis R. Preston's (1994) modification of MacLaury's VT. It elucidates how cognitive processes of coordinate selection and combination contribute to the on-line construction of category membership in the abstract…

Design and Implementation of a MAC Protocol for Timely and Reliable Delivery of Command and Data in Dynamic Wireless Sensor Networks

PubMed Central

Oh, Hoon; Van Vinh, Phan

2013-01-01

This paper proposes and implements a new TDMA-based MAC protocol for providing timely and reliable delivery of data and command for monitoring and control networks. In this kind of network, sensor nodes are required to sense data from the monitoring environment periodically and then send the data to a sink. The sink determines whether the environment is safe or not by analyzing the acquired data. Sometimes, a command or control message is sent from the sink to a particular node or a group of nodes to execute the services or request further interested data. The proposed MAC protocol enables bidirectional communication, controls active and sleep modes of a sensor node to conserve energy, and addresses the problem of load unbalancing between the nodes near a sink and the other nodes. It can improve reliability of communication significantly while extending network lifetime. These claims are supported by the experimental results. PMID:24084116

Design and implementation of a MAC protocol for timely and reliable delivery of command and data in dynamic wireless sensor networks.

PubMed

Oh, Hoon; Van Vinh, Phan

2013-09-30

This paper proposes and implements a new TDMA-based MAC protocol for providing timely and reliable delivery of data and command for monitoring and control networks. In this kind of network, sensor nodes are required to sense data from the monitoring environment periodically and then send the data to a sink. The sink determines whether the environment is safe or not by analyzing the acquired data. Sometimes, a command or control message is sent from the sink to a particular node or a group of nodes to execute the services or request further interested data. The proposed MAC protocol enables bidirectional communication, controls active and sleep modes of a sensor node to conserve energy, and addresses the problem of load unbalancing between the nodes near a sink and the other nodes. It can improve reliability of communication significantly while extending network lifetime. These claims are supported by the experimental results.

Right hemisphere damage: Communication processing in adults evaluated by the Brazilian Protocole MEC - Bateria MAC.

PubMed

Fonseca, Rochele Paz; Fachel, Jandyra Maria Guimarães; Chaves, Márcia Lorena Fagundes; Liedtke, Francéia Veiga; Parente, Maria Alice de Mattos Pimenta

2007-01-01

Right-brain-damaged individuals may present discursive, pragmatic, lexical-semantic and/or prosodic disorders. To verify the effect of right hemisphere damage on communication processing evaluated by the Brazilian version of the Protocole Montréal d'Évaluation de la Communication (Montreal Communication Evaluation Battery) - Bateria Montreal de Avaliação da Comunicação, Bateria MAC, in Portuguese. A clinical group of 29 right-brain-damaged participants and a control group of 58 non-brain-damaged adults formed the sample. A questionnaire on sociocultural and health aspects, together with the Brazilian MAC Battery was administered. Significant differences between the clinical and control groups were observed in the following MAC Battery tasks: conversational discourse, unconstrained, semantic and orthographic verbal fluency, linguistic prosody repetition, emotional prosody comprehension, repetition and production. Moreover, the clinical group was less homogeneous than the control group. A right-brain-damage effect was identified directly, on three communication processes: discursive, lexical-semantic and prosodic processes, and indirectly, on pragmatic process.

Design and performance evaluation of a distributed OFDMA-based MAC protocol for MANETs.

PubMed

Park, Jaesung; Chung, Jiyoung; Lee, Hyungyu; Lee, Jung-Ryun

2014-01-01

In this paper, we propose a distributed MAC protocol for OFDMA-based wireless mobile ad hoc multihop networks, in which the resource reservation and data transmission procedures are operated in a distributed manner. A frame format is designed considering the characteristics of OFDMA that each node can transmit or receive data to or from multiple nodes simultaneously. Under this frame structure, we propose a distributed resource management method including network state estimation and resource reservation processes. We categorize five types of logical errors according to their root causes and show that two of the logical errors are inevitable while three of them are avoided under the proposed distributed MAC protocol. In addition, we provide a systematic method to determine the advertisement period of each node by presenting a clear relation between the accuracy of estimated network states and the signaling overhead. We evaluate the performance of the proposed protocol in respect of the reservation success rate and the success rate of data transmission. Since our method focuses on avoiding logical errors, it could be easily placed on top of the other resource allocation methods focusing on the physical layer issues of the resource management problem and interworked with them.

Cognitive function and advanced kidney disease: longitudinal trends and impact on decision-making.

PubMed

Iyasere, Osasuyi; Okai, David; Brown, Edwina

2017-02-01

Background: Cognitive impairment commonly affects renal patients. But little is known about the influence of dialysis modality on cognitive trends or the influence of cognitive impairment on decision-making in renal patients. This study evaluated cognitive trends amongst chronic kidney disease (CKD), haemodialysis (HD) and peritoneal dialysis (PD) patients. The relationship between cognitive impairment and decision-making capacity (DMC) was also assessed. Methods: Patients were recruited from three outpatient clinics. Cognitive function was assessed 4-monthly for up to 2 years, using the Montreal Cognitive Assessment (MoCA) tool. Cognitive trends were assessed using mixed model analysis. DMC was assessed using the Macarthur Competency Assessment tool (MacCAT-T). MacCAT-T scores were compared between patients with cognitive impairment (MoCA <26) and those without. Results: In total, 102 (41 HD, 25 PD and 36 CKD) patients were recruited into the prospective study. After multivariate analysis, the total MoCA scores declined faster in dialysis compared with CKD patients [coefficient = -0.03, 95% confidence interval (95% CI) = -0.056 to - 0.004; P = 0.025]. The MoCA executive scores declined faster in the HD compared with PD patients (coefficient = -0.12, 95% CI = -0.233 to - 0.007; P = 0.037). DMC was assessed in 10 patients. Those with cognitive impairment had lower MacCAT-T compared with those without [median (interquartile range) 19 (17.9-19.6) versus 17.4 (16.3-18.4); P = 0.049]. Conclusions: Cognition declines faster in dialysis patients compared with CKD patients and in HD patients compared with PD patients. Cognitive impairment affects DMC in patients with advanced kidney disease.

Low Duty-Cycling MAC Protocol for Low Data-Rate Medical Wireless Body Area Networks

PubMed Central

Zhang, Chongqing; Wang, Yinglong; Liang, Yongquan; Shu, Minglei; Zhang, Jinquan; Ni, Lina

2017-01-01

Wireless body area networks (WBANs) are severely energy constrained, and how to improve the energy efficiency so as to prolong the network lifetime as long as possible is one of the most important goals of WBAN research. Low data-rate WBANs are promising to cut down the energy consumption and extend the network lifetime. Considering the characteristics and demands of low data-rate WBANs, a low duty-cycling medium access control (MAC) protocol is specially designed for this kind of WBAN in this paper. Longer superframes are exploited to cut down the energy consumed on the transmissions and receptions of redundant beacon frames. Insertion time slots are embedded into the inactive part of a superframe to deliver the frames and satisfy the quality of service (QoS) requirements. The number of the data subsections in an insertion time slot can be adaptively adjusted so as to accommodate low data-rate WBANs with different traffic. Simulation results show that the proposed MAC protocol performs well under the condition of low data-rate monitoring traffic. PMID:28509849

Behavior Therapy for Pediatric Trichotillomania: A Randomized Controlled Trial

ERIC Educational Resources Information Center

Franklin, Martin E.; Edson, Aubrey L.; Ledley, Deborah A.; Cahill, Shawn P.

2011-01-01

Objective: To examine the efficacy and durability of a behavioral therapy (BT) protocol for pediatric TTM compared with a minimal attention control (MAC) condition. It was hypothesized that the BT condition would be superior to MAC at the end of acute treatment, and would also demonstrate durability of gains through the maintenance treatment…

Right hemisphere damage: Communication processing in adults evaluated by the Brazilian Protocole MEC – Bateria MAC

PubMed Central

Fonseca, Rochele Paz; Fachel, Jandyra Maria Guimarães; Chaves, Márcia Lorena Fagundes; Liedtke, Francéia Veiga; Parente, Maria Alice de Mattos Pimenta

2007-01-01

Right-brain-damaged individuals may present discursive, pragmatic, lexical-semantic and/or prosodic disorders. Objective To verify the effect of right hemisphere damage on communication processing evaluated by the Brazilian version of the Protocole Montréal d’Évaluation de la Communication (Montreal Communication Evaluation Battery) – Bateria Montreal de Avaliação da Comunicação, Bateria MAC, in Portuguese. Methods A clinical group of 29 right-brain-damaged participants and a control group of 58 non-brain-damaged adults formed the sample. A questionnaire on sociocultural and health aspects, together with the Brazilian MAC Battery was administered. Results Significant differences between the clinical and control groups were observed in the following MAC Battery tasks: conversational discourse, unconstrained, semantic and orthographic verbal fluency, linguistic prosody repetition, emotional prosody comprehension, repetition and production. Moreover, the clinical group was less homogeneous than the control group. Conclusions A right-brain-damage effect was identified directly, on three communication processes: discursive, lexical-semantic and prosodic processes, and indirectly, on pragmatic process. PMID:29213400

Exploitation of Existing Voice Over Internet Protocol Technology for Department of the Navy Application

DTIC Science & Technology

2002-09-01

Protocol LAN Local Area Network LDAP Lightweight Directory Access Protocol LLQ Low Latency Queuing MAC Media Access Control MarCorSysCom Marine...Description Protocol SIP Session Initiation Protocol SMTP Simple Mail Transfer Protocol SPAWAR Space and Naval Warfare Systems Center SS7 ...PSTN infrastructure previously required to carry the conversation. The cost of accessing the PSTN is thereby eliminated. In cases where Internet

Traffic Management for Emergency Vehicle Priority Based on Visual Sensing.

PubMed

Nellore, Kapileswar; Hancke, Gerhard P

2016-11-10

Vehicular traffic is endlessly increasing everywhere in the world and can cause terrible traffic congestion at intersections. Most of the traffic lights today feature a fixed green light sequence, therefore the green light sequence is determined without taking the presence of the emergency vehicles into account. Therefore, emergency vehicles such as ambulances, police cars, fire engines, etc. stuck in a traffic jam and delayed in reaching their destination can lead to loss of property and valuable lives. This paper presents an approach to schedule emergency vehicles in traffic. The approach combines the measurement of the distance between the emergency vehicle and an intersection using visual sensing methods, vehicle counting and time sensitive alert transmission within the sensor network. The distance between the emergency vehicle and the intersection is calculated for comparison using Euclidean distance, Manhattan distance and Canberra distance techniques. The experimental results have shown that the Euclidean distance outperforms other distance measurement techniques. Along with visual sensing techniques to collect emergency vehicle information, it is very important to have a Medium Access Control (MAC) protocol to deliver the emergency vehicle information to the Traffic Management Center (TMC) with less delay. Then only the emergency vehicle is quickly served and can reach the destination in time. In this paper, we have also investigated the MAC layer in WSNs to prioritize the emergency vehicle data and to reduce the transmission delay for emergency messages. We have modified the medium access procedure used in standard IEEE 802.11p with PE-MAC protocol, which is a new back off selection and contention window adjustment scheme to achieve low broadcast delay for emergency messages. A VANET model for the UTMS is developed and simulated in NS-2. The performance of the standard IEEE 802.11p and the proposed PE-MAC is analysed in detail. The NS-2 simulation results have shown that the PE-MAC outperforms the IEEE 802.11p in terms of average end-to-end delay, throughput and energy consumption. The performance evaluation results have proven that the proposed PE-MAC prioritizes the emergency vehicle data and delivers the emergency messages to the TMC with less delay compared to the IEEE 802.11p. The transmission delay of the proposed PE-MAC is also compared with the standard IEEE 802.15.4, and Enhanced Back-off Selection scheme for IEEE 802.15.4 protocol [EBSS, an existing protocol to ensure fast transmission of the detected events on the road towards the TMC] and the comparative results have proven the effectiveness of the PE-MAC over them. Furthermore, this research work will provide an insight into the design of an intelligent urban traffic management system for the effective management of emergency vehicles and will help to save lives and property.

Scalable Lunar Surface Networks and Adaptive Orbit Access

NASA Technical Reports Server (NTRS)

Wang, Xudong

2015-01-01

Teranovi Technologies, Inc., has developed innovative network architecture, protocols, and algorithms for both lunar surface and orbit access networks. A key component of the overall architecture is a medium access control (MAC) protocol that includes a novel mechanism of overlaying time division multiple access (TDMA) and carrier sense multiple access with collision avoidance (CSMA/CA), ensuring scalable throughput and quality of service. The new MAC protocol is compatible with legacy Institute of Electrical and Electronics Engineers (IEEE) 802.11 networks. Advanced features include efficiency power management, adaptive channel width adjustment, and error control capability. A hybrid routing protocol combines the advantages of ad hoc on-demand distance vector (AODV) routing and disruption/delay-tolerant network (DTN) routing. Performance is significantly better than AODV or DTN and will be particularly effective for wireless networks with intermittent links, such as lunar and planetary surface networks and orbit access networks.

Design of the frame structure for a multiservice interactive system using ATM-PON

NASA Astrophysics Data System (ADS)

Nam, Jae-Hyun; Jang, Jongwook; Lee, Jung-Tae

1998-10-01

The MAC (Medium Access Control) protocol controls B-NT1s' (Optical Network Unit) access to the shared capacity on the PON, this protocol is very important if TDMA (Time Division Multiple Access) multiplexing is used on the upstream. To control the upstream traffic some kind of access protocol has to be implemented. There are roughly two different approaches to use request cells: in a collision free way or such that collisions in a request slot are allowed. It is the objective of this paper to describe a MAC-protocol structure that supports both approaches and hybrids of it. In our paper we grantee the QoS (Quality of Service) of each B-NT1 through LOC, LOV, LOA field that are the length field of the transmitted cell at each B-NT1. Each B-NT1 transmits its status of request on request cell.

Actively station: Effects on global cognition of mature adults and healthy elderly program using eletronic games

PubMed Central

Ordonez, Tiago Nascimento; Borges, Felipe; Kanashiro, Camila Sato; Santos, Carolina Carneiro das Neves; Hora, Samara Santos; Lima-Silva, Thais Bento

2017-01-01

Studies show that aging is accompanied by decline in cognitive functions but also indicate that interventions, such as training on electronic games, can enhance performance and promote maintenance of cognitive abilities in healthy older adults. Objective To investigate the effects of an electronic game program, called Actively Station, on the performance of global cognition of adults aged over 50 years. Methods 124 mature and elderly adults enrolled in the "Actively Station" cognitive stimulation program of São Caetano do Sul City, in the State of São Paulo, participated in training for learning of electronic games. Participants were divided into two groups: training group (TG) n=102 and control group (CG) n=22. Protocol: a sociodemographic questionnaire, the Mini-Mental State Examination (MMSE), the Addenbrooke's Cognitive Examination Revised (ACE-R), the Memory Complaint Questionnaire (MAC-Q), the scale of frequency of forgetfulness, the Geriatric Depression Scale (GDS-15), the Geriatric Anxiety Inventory (GAI), the Global Satisfaction with Life Scale, and two scales on learning in the training. Results The cognitive performance of the TG improved significantly after the program, particularly in the domains of language and memory, and there was a decrease on the anxiety index and frequency of memory complaints, when compared to the CG. Conclusion These findings suggest that the acquisition of new knowledge and the use of new stimuli, such as electronic games, can promote improvements in cognition and mood and reduce the frequency of memory complaints. PMID:29213510

Traffic Management for Emergency Vehicle Priority Based on Visual Sensing

PubMed Central

Nellore, Kapileswar; Hancke, Gerhard P.

2016-01-01

Vehicular traffic is endlessly increasing everywhere in the world and can cause terrible traffic congestion at intersections. Most of the traffic lights today feature a fixed green light sequence, therefore the green light sequence is determined without taking the presence of the emergency vehicles into account. Therefore, emergency vehicles such as ambulances, police cars, fire engines, etc. stuck in a traffic jam and delayed in reaching their destination can lead to loss of property and valuable lives. This paper presents an approach to schedule emergency vehicles in traffic. The approach combines the measurement of the distance between the emergency vehicle and an intersection using visual sensing methods, vehicle counting and time sensitive alert transmission within the sensor network. The distance between the emergency vehicle and the intersection is calculated for comparison using Euclidean distance, Manhattan distance and Canberra distance techniques. The experimental results have shown that the Euclidean distance outperforms other distance measurement techniques. Along with visual sensing techniques to collect emergency vehicle information, it is very important to have a Medium Access Control (MAC) protocol to deliver the emergency vehicle information to the Traffic Management Center (TMC) with less delay. Then only the emergency vehicle is quickly served and can reach the destination in time. In this paper, we have also investigated the MAC layer in WSNs to prioritize the emergency vehicle data and to reduce the transmission delay for emergency messages. We have modified the medium access procedure used in standard IEEE 802.11p with PE-MAC protocol, which is a new back off selection and contention window adjustment scheme to achieve low broadcast delay for emergency messages. A VANET model for the UTMS is developed and simulated in NS-2. The performance of the standard IEEE 802.11p and the proposed PE-MAC is analysed in detail. The NS-2 simulation results have shown that the PE-MAC outperforms the IEEE 802.11p in terms of average end-to-end delay, throughput and energy consumption. The performance evaluation results have proven that the proposed PE-MAC prioritizes the emergency vehicle data and delivers the emergency messages to the TMC with less delay compared to the IEEE 802.11p. The transmission delay of the proposed PE-MAC is also compared with the standard IEEE 802.15.4, and Enhanced Back-off Selection scheme for IEEE 802.15.4 protocol [EBSS, an existing protocol to ensure fast transmission of the detected events on the road towards the TMC] and the comparative results have proven the effectiveness of the PE-MAC over them. Furthermore, this research work will provide an insight into the design of an intelligent urban traffic management system for the effective management of emergency vehicles and will help to save lives and property. PMID:27834924

A memory and organizational aid improves Alzheimer disease research consent capacity: results of a randomized, controlled trial.

PubMed

Rubright, Jonathan; Sankar, Pamela; Casarett, David J; Gur, Ruben; Xie, Sharon X; Karlawish, Jason

2010-12-01

Early and progressive cognitive impairments of patients with Alzheimer disease (AD) hinder their capacity to provide informed consent. Unfortunately, the limited research on techniques to improve capacity has shown mixed results. Therefore, the authors tested whether a memory and organizational aid improves the performance of patients with AD on measures of capacity and competency to give informed consent. Patients with AD randomly assigned to standard consent or standard plus a memory and organizational aid. Memory and organizational aid summarized the content of information mandated under the informed consent disclosure requirements of the Common Rule at a sixth grade reading level. Three psychiatrists without access to patient data independently reviewed MacArthur Competence Assessment Tool for Clinical Research (MacCAT-CR) interview transcripts to judge whether the patient was capable of providing informed consent. The agreement of at least two of the three experts defined a participant as capable of providing informed consent. Secondary outcomes are MacCAT-CR measures of understanding, appreciation and reasoning, and comparison with cognitively normal older adult norms. AD intervention and control groups were similar in terms of age, education, and cognitive status. The intervention group was more likely to be judged competent than control group and had higher scores on MacCAT-CR measure of understanding. The intervention had no effect on the measures of appreciation or reasoning. A consent process that addresses the deficits in memory and attention of a patient with AD can improve capacity to give informed consent for early phase AD research. The results also validate the MacCAT-CR as an instrument to measure capacity, especially the understanding subscale. ClinicalTrials.Gov#NCT00105612, http://clinicaltrials.gov/show/NCT00105612.

A memory and organizational aid improves AD research consent capacity: Results of a randomized, controlled trial

PubMed Central

Rubright, Jonathan; Sankar, Pamela; Casarett, David J; Gur, Ruben; Xie, Sharon X; Karlawish, Jason

2010-01-01

Objectives AD patients' early and progressive cognitive impairments hinder their capacity to provide informed consent. Unfortunately, the limited research on techniques to improve capacity has shown mixed results. Therefore, we tested whether a memory and organizational aid improves AD patient performance on measures of capacity and competency to give informed consent. Design, Setting, and Participants AD patients randomly assigned to standard consent, or standard plus a memory and organizational aid. Intervention Memory and organizational aid summarized at a 6th grade reading level the content of information mandated under the Common Rule's informed consent disclosure requirements. Measurements Three psychiatrists without access to patient data independently reviewed MacArthur Competence Assessment Tool for Clinical Research (MacCAT-CR) interview transcripts to judge whether the patient was capable of providing informed consent. The agreement of at least two of three experts defined a participant as capable of providing informed consent. Secondary outcomes are MacCAT-CR measures of understanding, appreciation and reasoning, and comparison to cognitively normal older adult norms. Results AD intervention and control groups were similar in terms of age, education, and cognitive status. The intervention group was more likely to be judged competent than control group and had higher scores on MacCAT-CR measure of understanding. The intervention had no effect on measures of appreciation or reasoning. Conclusions A consent process that addresses an AD patients' deficits in memory and attention can improve capacity to give informed consent for early phase AD research. The results also validate the MacCAT-CR as an instrument to measure capacity, especially the understanding subscale. PMID:20808101

The Bridge: Linking Mood Induction, Self-Report, and Psychophysiology to Vocabulary Learning on a Paired-Associates Learning Task

ERIC Educational Resources Information Center

Fox, Jessica Kate

2017-01-01

Researchers in the field of second language acquisition continue to establish links between cognition and emotion (Dewaele, 2013; MacIntyre, 2002; MacIntyre & Gardner, 1989, 1991b, 1994; Segalowitz & Trofimovich, 2011). The purpose of the present study is to investigate to what extent physiological and self-report measures predict…

Semi-automated protocol for purification of Mycobacterium leprae from tissues using the gentleMACS™ Octo Dissociator.

PubMed

Williams, Diana L; Adams, Linda B; Lahiri, Ramanuj

2014-10-01

Mycobacterium leprae, etiologic agent of leprosy, is propagated in athymic nude mouse footpads (FPs). The current purification protocol is tedious and physically demanding. A simpler, semi-automated protocol was developed using gentleMACS™ Octo Dissociator. The gentleMACS protocol provided a very effective means for purification of highly viable M. leprae from tissue. Copyright © 2014. Published by Elsevier B.V.

Distributed Multiple Access Control for the Wireless Mesh Personal Area Networks

NASA Astrophysics Data System (ADS)

Park, Moo Sung; Lee, Byungjoo; Rhee, Seung Hyong

Mesh networking technologies for both high-rate and low-rate wireless personal area networks (WPANs) are under development by several standardization bodies. They are considering to adopt distributed TDMA MAC protocols to provide seamless user mobility as well as a good peer-to-peer QoS in WPAN mesh. It has been, however, pointed out that the absence of a central controller in the wireless TDMA MAC may cause a severe performance degradation: e. g., fair allocation, service differentiation, and admission control may be hard to achieve or can not be provided. In this paper, we suggest a new framework of resource allocation for the distributed MAC protocols in WPANs. Simulation results show that our algorithm achieves both a fair resource allocation and flexible service differentiations in a fully distributed way for mesh WPANs where the devices have high mobility and various requirements. We also provide an analytical modeling to discuss about its unique equilibrium and to compute the lengths of reserved time slots at the stable point.

[Spanish validation of the MacArthur Competence Assessment Tool for Treatment interview to assess patients competence to consent treatment].

PubMed

Alvarez Marrodán, Ignacio; Baón Pérez, Beatriz; Navío Acosta, Mercedes; López-Antón, Raul; Lobo Escolar, Elena; Ventura Faci, Tirso

2014-09-09

To validate the MacArthur Competence Assessment Tool for Treatment (MacCAT-T) Spanish version, which assesses the mental capacity of patients to consent treatment, by examining 4 areas (Understanding, Appreciation, Reasoning and Expressing a choice). 160 subjects (80 Internal Medicine inpatients, 40 Psychiatric inpatients and 40 healthy controls). MacCAT-T, Mini-Mental Status Examination (MMSE). Feasibility study, reliability and validity calculations (against to gold standard of clinical expert). Mean duration of the MacCAT-T interview was 18min. Inter-rater reliability: Intraclass correlation coefficient for Understanding=0.98, Appreciation=0.97, Reasoning=0.98, Expressing a choice=0.91. Internal consistency (Cronbach's alpha): Understanding=0.87, for Appreciation=0.76, for Reasoning=0.86. Patients considered to be incapable (gold standard) scored lower in all the MacCAT-T areas. Poor performance on the MacCAT-T was related to cognitive impairment assessed by MMSE. Spanish version of the MacCAT-T is feasible, reliable, and valid for assessing the capacity of patients to consent treatment. Copyright © 2013 Elsevier España, S.L. All rights reserved.

LAN attack detection using Discrete Event Systems.

PubMed

Hubballi, Neminath; Biswas, Santosh; Roopa, S; Ratti, Ritesh; Nandi, Sukumar

2011-01-01

Address Resolution Protocol (ARP) is used for determining the link layer or Medium Access Control (MAC) address of a network host, given its Internet Layer (IP) or Network Layer address. ARP is a stateless protocol and any IP-MAC pairing sent by a host is accepted without verification. This weakness in the ARP may be exploited by malicious hosts in a Local Area Network (LAN) by spoofing IP-MAC pairs. Several schemes have been proposed in the literature to circumvent these attacks; however, these techniques either make IP-MAC pairing static, modify the existing ARP, patch operating systems of all the hosts etc. In this paper we propose a Discrete Event System (DES) approach for Intrusion Detection System (IDS) for LAN specific attacks which do not require any extra constraint like static IP-MAC, changing the ARP etc. A DES model is built for the LAN under both a normal and compromised (i.e., spoofed request/response) situation based on the sequences of ARP related packets. Sequences of ARP events in normal and spoofed scenarios are similar thereby rendering the same DES models for both the cases. To create different ARP events under normal and spoofed conditions the proposed technique uses active ARP probing. However, this probing adds extra ARP traffic in the LAN. Following that a DES detector is built to determine from observed ARP related events, whether the LAN is operating under a normal or compromised situation. The scheme also minimizes extra ARP traffic by probing the source IP-MAC pair of only those ARP packets which are yet to be determined as genuine/spoofed by the detector. Also, spoofed IP-MAC pairs determined by the detector are stored in tables to detect other LAN attacks triggered by spoofing namely, man-in-the-middle (MiTM), denial of service etc. The scheme is successfully validated in a test bed. Copyright © 2010 ISA. Published by Elsevier Ltd. All rights reserved.

Traffic Adaptive Energy Efficient and Low Latency Medium Access Control for Wireless Sensor Networks

NASA Astrophysics Data System (ADS)

Yadav, Rajesh; Varma, Shirshu; Malaviya, N.

2008-05-01

Medium access control for wireless sensor networks has been a very active research area in the recent years. The traditional wireless medium access control protocol such as IEEE 802.11 is not suitable for the sensor network application because these are battery powered. The recharging of these sensor nodes is expensive and also not possible. The most of the literature in the medium access for the sensor network focuses on the energy efficiency. The proposed MAC protocol solves the energy inefficiency caused by idle listening, control packet overhead and overhearing taking nodes latency into consideration based on the network traffic. Simulation experiments have been performed to demonstrate the effectiveness of the proposed approach. The validation of the simulation results of the proposed MAC has been done by comparing it with the analytical model. This protocol has been simulated in Network Simulator ns-2.

An Energy-Efficient MAC Protocol for Medical Emergency Monitoring Body Sensor Networks

PubMed Central

Zhang, Chongqing; Wang, Yinglong; Liang, Yongquan; Shu, Minglei; Chen, Changfang

2016-01-01

Medical emergency monitoring body sensor networks (BSNs) monitor the occurrence of medical emergencies and are helpful for the daily care of the elderly and chronically ill people. Such BSNs are characterized by rare traffic when there is no emergency occurring, high real-time and reliable requirements of emergency data and demand for a fast wake-up mechanism for waking up all nodes when an emergency happens. A beacon-enabled MAC protocol is specially designed to meet the demands of medical emergency monitoring BSNs. The rarity of traffic is exploited to improve energy efficiency. By adopting a long superframe structure to avoid unnecessary beacons and allocating most of the superframe to be inactive periods, the duty cycle is reduced to an extremely low level to save energy. Short active time slots are interposed into the superframe and shared by all of the nodes to deliver the emergency data in a low-delay and reliable way to meet the real-time and reliable requirements. The interposition slots can also be used by the coordinator to broadcast network demands to wake-up all nodes in a low-delay and energy-efficient way. Experiments display that the proposed MAC protocol works well in BSNs with low emergency data traffic. PMID:26999145

Low Latency MAC Protocol in Wireless Sensor Networks Using Timing Offset

NASA Astrophysics Data System (ADS)

Choi, Seung Sik

This paper proposes a low latency MAC protocol that can be used in sensor networks. To extend the lifetime of sensor nodes, the conventional solution is to synchronize active/sleep periods of all sensor nodes. However, due to these synchronized sensor nodes, packets in the intermediate nodes must wait until the next node wakes up before it can forward a packet. This induces a large delay in sensor nodes. To solve this latency problem, a clustered sensor network which uses two types of sensor nodes and layered architecture is considered. Clustered heads in each cluster are synchronized with different timing offsets to reduce the sleep delay. Using this concept, the latency problem can be solved and more efficient power usage can be obtained.

IEEE 802.15.4 Frame Aggregation Enhancement to Provide High Performance in Life-Critical Patient Monitoring Systems

PubMed Central

Akbar, Muhammad Sajjad; Yu, Hongnian; Cang, Shuang

2017-01-01

In wireless body area sensor networks (WBASNs), Quality of Service (QoS) provision for patient monitoring systems in terms of time-critical deadlines, high throughput and energy efficiency is a challenging task. The periodic data from these systems generates a large number of small packets in a short time period which needs an efficient channel access mechanism. The IEEE 802.15.4 standard is recommended for low power devices and widely used for many wireless sensor networks applications. It provides a hybrid channel access mechanism at the Media Access Control (MAC) layer which plays a key role in overall successful transmission in WBASNs. There are many WBASN’s MAC protocols that use this hybrid channel access mechanism in variety of sensor applications. However, these protocols are less efficient for patient monitoring systems where life critical data requires limited delay, high throughput and energy efficient communication simultaneously. To address these issues, this paper proposes a frame aggregation scheme by using the aggregated-MAC protocol data unit (A-MPDU) which works with the IEEE 802.15.4 MAC layer. To implement the scheme accurately, we develop a traffic patterns analysis mechanism to understand the requirements of the sensor nodes in patient monitoring systems, then model the channel access to find the performance gap on the basis of obtained requirements, finally propose the design based on the needs of patient monitoring systems. The mechanism is initially verified using numerical modelling and then simulation is conducted using NS2.29, Castalia 3.2 and OMNeT++. The proposed scheme provides the optimal performance considering the required QoS. PMID:28134853

IEEE 802.15.4 Frame Aggregation Enhancement to Provide High Performance in Life-Critical Patient Monitoring Systems.

PubMed

Akbar, Muhammad Sajjad; Yu, Hongnian; Cang, Shuang

2017-01-28

In wireless body area sensor networks (WBASNs), Quality of Service (QoS) provision for patient monitoring systems in terms of time-critical deadlines, high throughput and energy efficiency is a challenging task. The periodic data from these systems generates a large number of small packets in a short time period which needs an efficient channel access mechanism. The IEEE 802.15.4 standard is recommended for low power devices and widely used for many wireless sensor networks applications. It provides a hybrid channel access mechanism at the Media Access Control (MAC) layer which plays a key role in overall successful transmission in WBASNs. There are many WBASN's MAC protocols that use this hybrid channel access mechanism in variety of sensor applications. However, these protocols are less efficient for patient monitoring systems where life critical data requires limited delay, high throughput and energy efficient communication simultaneously. To address these issues, this paper proposes a frame aggregation scheme by using the aggregated-MAC protocol data unit (A-MPDU) which works with the IEEE 802.15.4 MAC layer. To implement the scheme accurately, we develop a traffic patterns analysis mechanism to understand the requirements of the sensor nodes in patient monitoring systems, then model the channel access to find the performance gap on the basis of obtained requirements, finally propose the design based on the needs of patient monitoring systems. The mechanism is initially verified using numerical modelling and then simulation is conducted using NS2.29, Castalia 3.2 and OMNeT++. The proposed scheme provides the optimal performance considering the required QoS.

High-throughput and low-latency 60GHz small-cell network architectures over radio-over-fiber technologies

NASA Astrophysics Data System (ADS)

Pleros, N.; Kalfas, G.; Mitsolidou, C.; Vagionas, C.; Tsiokos, D.; Miliou, A.

2017-01-01

Future broadband access networks in the 5G framework will need to be bilateral, exploiting both optical and wireless technologies. This paper deals with new approaches and synergies on radio-over-fiber (RoF) technologies and how those can be leveraged to seamlessly converge wireless technology for agility and mobility with passive optical networks (PON)-based backhauling. The proposed convergence paradigm is based upon a holistic network architecture mixing mm-wave wireless access with photonic integration, dynamic capacity allocation and network coding schemes to enable high bandwidth and low-latency fixed and 60GHz wireless personal area communications for gigabit rate per user, proposing and deploying on top a Medium-Transparent MAC (MT-MAC) protocol as a low-latency bandwidth allocation mechanism. We have evaluated alternative network topologies between the central office (CO) and the access point module (APM) for data rates up to 2.5 Gb/s and SC frequencies up to 60 GHz. Optical network coding is demonstrated for SCM-based signaling to enhance bandwidth utilization and facilitate optical-wireless convergence in 5G applications, reporting medium-transparent network coding directly at the physical layer between end-users communicating over a RoF infrastructure. Towards equipping the physical layer with the appropriate agility to support MT-MAC protocols, a monolithic InP-based Remote Antenna Unit optoelectronic PIC interface is shown that ensures control over the optical resource allocation assisting at the same time broadband wireless service. Finally, the MT-MAC protocol is analysed and simulation and analytical theoretical results are presented that are found to be in good agreement confirming latency values lower than 1msec for small- to mid-load conditions.

Parental Loss and Eating-Related Cognitions and Behaviors in College-Age Women

ERIC Educational Resources Information Center

Beam, Minna R.; Servaty-Seib, Heather L.; Mathews, Laura

2004-01-01

To examine the eating-related cognitions and behaviors of college-age women who had experienced parental death, parental divorce, or neither loss condition, we recruited 48 women from science and social science departments at a state university in the Southeast. All participants completed the Mizes Anorectic Cognitions Scale (MAC) and the Bulimia…

MAC Protocol for Ad Hoc Networks Using a Genetic Algorithm

PubMed Central

Elizarraras, Omar; Panduro, Marco; Méndez, Aldo L.

2014-01-01

The problem of obtaining the transmission rate in an ad hoc network consists in adjusting the power of each node to ensure the signal to interference ratio (SIR) and the energy required to transmit from one node to another is obtained at the same time. Therefore, an optimal transmission rate for each node in a medium access control (MAC) protocol based on CSMA-CDMA (carrier sense multiple access-code division multiple access) for ad hoc networks can be obtained using evolutionary optimization. This work proposes a genetic algorithm for the transmission rate election considering a perfect power control, and our proposition achieves improvement of 10% compared with the scheme that handles the handshaking phase to adjust the transmission rate. Furthermore, this paper proposes a genetic algorithm that solves the problem of power combining, interference, data rate, and energy ensuring the signal to interference ratio in an ad hoc network. The result of the proposed genetic algorithm has a better performance (15%) compared to the CSMA-CDMA protocol without optimizing. Therefore, we show by simulation the effectiveness of the proposed protocol in terms of the throughput. PMID:25140339

Performance evaluation of complete data transfer of physical layer according to IEEE 802.15.4 standard

NASA Astrophysics Data System (ADS)

Raju, Kota Solomon; Merugu, Naresh Babu; Neetu, Babu, E. Ram

2016-03-01

ZigBee is well-accepted industrial standard for wireless sensor networks based on IEEE 802.15.4 standard. Wireless Sensor Networks is the major concern of communication these days. These Wireless Sensor Networks investigate the properties of networks of small battery-powered sensors with wireless communication. The communication between any two wireless nodes of wireless sensor networks is carried out through a protocol stack. This protocol stack has been designed by different vendors in various ways. Every custom vendor possesses his own protocol stack and algorithms especially at the MAC layer. But, many applications require modifications in their algorithms at various layers as per their requirements, especially energy efficient protocols at MAC layer that are simulated in Wireless sensor Network Simulators which are not being tested in real time systems because vendors do not allow the programmability of each layer in their protocol stack. This problem can be quoted as Vendor-Interoperability. The solution is to develop the programmable protocol stack where we can design our own application as required. As a part of the task first we tried implementing physical layer and transmission of data using physical layer. This paper describes about the transmission of the total number of bytes of Frame according to the IEEE 802.15.4 standard using Physical Layer.

ZEA-TDMA: design and system level implementation of a TDMA protocol for anonymous wireless networks

NASA Astrophysics Data System (ADS)

Banerjee, Debasmit; Dong, Bo; Biswas, Subir

2013-05-01

Wireless sensor network used in military applications may be deployed in hostile environments, where privacy and security is of primary concern. This can lead to the formation of a trust-based sub-network among mutually-trusting nodes. However, designing a TDMA MAC protocol is very challenging in situations where such multiple sub-networks coexist, since TDMA protocols require node identity information for slot assignments. This paper introduces a novel distributed TDMA MAC protocol, ZEA-TDMA (Zero Exposure Anonymous TDMA), for anonymous wireless networks. ZEA-TDMA achieves slot allocation with strict anonymity constraints, i.e. without nodes having to exchange any identity revealing information. By using just the relative time of arrival of packets and a novel technique of wireless collision-detection and resolution for fixed packetsizes, ZEA-TDMA is able to achieve MAC slot-allocation which is described as follows. Initially, a newly joined node listens to its one-hop neighborhood channel usage and creates a slot allocation table based on its own relative time, and finally, selects a slot that is collision free within its one-hop neighborhood. The selected slot can however cause hidden collisions with a two-hop neighbor of the node. These collisions are resolved by a common neighbor of the colliding nodes, which first detects the collision, and then resolve them using an interrupt packet. ZEA-TDMA provides the following features: a) it is a TDMA protocol ideally suited for highly secure or strictly anonymous environments b) it can be used in heterogeneous environments where devices use different packet structures c) it does not require network time-synchronization, and d) it is insensitive to channel errors. We have implemented ZEA-TDMA on the MICA2 hardware platform running TinyOS and evaluated the protocol functionality and performance on a MICA2 test-bed.

Performance Analysis of Modified Accelerative Preallocation MAC Protocol for Passive Star-Coupled WDMA Networks

NASA Astrophysics Data System (ADS)

Yun, Changho; Kim, Kiseon

2006-04-01

For the passive star-coupled wavelength-division multiple-access (WDMA) network, a modified accelerative preallocation WDMA (MAP-WDMA) media access control (MAC) protocol is proposed, which is based on AP-WDMA. To show the advantages of MAP-WDMA as an adequate MAC protocol for the network over AP-WDMA, the channel utilization, the channel-access delay, and the latency of MAP-WDMA are investigated and compared with those of AP-WDMA under various data traffic patterns, including uniform, quasi-uniform type, disconnected type, mesh type, and ring type data traffics, as well as the assumption that a given number of network stations is equal to that of channels, in other words, without channel sharing. As a result, the channel utilization of MAP-WDMA can be competitive with respect to that of AP-WDMA at the expense of insignificantly higher latency. Namely, if the number of network stations is small, MAP-WDMA provides better channel utilization for uniform, quasi-uniform-type, and disconnected-type data traffics at all data traffic loads, as well as for mesh and ring-type data traffics at low data traffic loads. Otherwise, MAP-WDMA only outperforms AP-WDMA for the first three data traffics at higher data traffic loads. In the aspect of channel-access delay, MAP-WDMA gives better performance than AP-WDMA, regardless of data traffic patterns and the number of network stations.

Design and FPGA implementation for MAC layer of Ethernet PON

NASA Astrophysics Data System (ADS)

Zhu, Zengxi; Lin, Rujian; Chen, Jian; Ye, Jiajun; Chen, Xinqiao

2004-04-01

Ethernet passive optical network (EPON), which represents the convergence of low-cost, high-bandwidth and supporting multiple services, appears to be one of the best candidates for the next-generation access network. The work of standardizing EPON as a solution for access network is still underway in the IEEE802.3ah Ethernet in the first mile (EFM) task force. The final release is expected in 2004. Up to now, there has been no standard application specific integrated circuit (ASIC) chip available which fulfills the functions of media access control (MAC) layer of EPON. The MAC layer in EPON system has many functions, such as point-to-point emulation (P2PE), Ethernet MAC functionality, multi-point control protocol (MPCP), network operation, administration and maintenance (OAM) and link security. To implement those functions mentioned above, an embedded real-time operating system (RTOS) and a flexible programmable logic device (PLD) with an embedded processor are used. The software and hardware functions in MAC layer are realized through programming embedded microprocessor and field programmable gate array(FPGA). Finally, some experimental results are given in this paper. The method stated here can provide a valuable reference for developing EPON MAC layer ASIC.

Performance analysis and improvement of WPAN MAC for home networks.

PubMed

Mehta, Saurabh; Kwak, Kyung Sup

2010-01-01

The wireless personal area network (WPAN) is an emerging wireless technology for future short range indoor and outdoor communication applications. The IEEE 802.15.3 medium access control (MAC) is proposed to coordinate the access to the wireless medium among the competing devices, especially for short range and high data rate applications in home networks. In this paper we use analytical modeling to study the performance analysis of WPAN (IEEE 802.15.3) MAC in terms of throughput, efficient bandwidth utilization, and delay with various ACK policies under error channel condition. This allows us to introduce a K-Dly-ACK-AGG policy, payload size adjustment mechanism, and Improved Backoff algorithm to improve the performance of the WPAN MAC. Performance evaluation results demonstrate the impact of our improvements on network capacity. Moreover, these results can be very useful to WPAN application designers and protocol architects to easily and correctly implement WPAN for home networking.

Performance Analysis and Improvement of WPAN MAC for Home Networks

PubMed Central

Mehta, Saurabh; Kwak, Kyung Sup

2010-01-01

The wireless personal area network (WPAN) is an emerging wireless technology for future short range indoor and outdoor communication applications. The IEEE 802.15.3 medium access control (MAC) is proposed to coordinate the access to the wireless medium among the competing devices, especially for short range and high data rate applications in home networks. In this paper we use analytical modeling to study the performance analysis of WPAN (IEEE 802.15.3) MAC in terms of throughput, efficient bandwidth utilization, and delay with various ACK policies under error channel condition. This allows us to introduce a K-Dly-ACK-AGG policy, payload size adjustment mechanism, and Improved Backoff algorithm to improve the performance of the WPAN MAC. Performance evaluation results demonstrate the impact of our improvements on network capacity. Moreover, these results can be very useful to WPAN application designers and protocol architects to easily and correctly implement WPAN for home networking. PMID:22319274

MacArthur Competence Assessment Tool for Treatment in Alzheimer disease: cross-cultural adaptation.

PubMed

Santos, Raquel Luiza; Sousa, Maria Fernanda Barroso de; Simões, José Pedro; Bertrand, Elodie; Mograbi, Daniel C; Landeira-Fernandez, Jesus; Laks, Jerson; Dourado, Marcia Cristina Nascimento

2017-01-01

We adapted the MacArthur Competence Assessment Tool for Treatment (MacCAT-T) to Brazilian Portuguese, pilot testing it on mild and moderate patients with Alzheimer's disease (AD). The cross-cultural process required six steps. Sixty-six patients with AD were assessed for competence to consent to treatment, global cognition, working memory, awareness of disease, functionality, depressive symptoms and dementia severity. The items had semantic, idiomatic, conceptual and experiential equivalence. We found no difference between mild and moderate patients with AD on the MacCAT-T domains. The linear regressions showed that reasoning (p = 0.000) and functional status (p = 0.003) were related to understanding. Understanding (p = 0.000) was related to appreciation and reasoning. Awareness of disease (p = 0.001) was related to expressing a choice. The MacCAT-T adaptation was well-understood and the constructs of the original version were maintained. The results of the pilot study demonstrated an available Brazilian tool focused on decision-making capacity in AD.

On the MAC/network/energy performance evaluation of Wireless Sensor Networks: Contrasting MPH, AODV, DSR and ZTR routing protocols.

PubMed

Del-Valle-Soto, Carolina; Mex-Perera, Carlos; Orozco-Lugo, Aldo; Lara, Mauricio; Galván-Tejada, Giselle M; Olmedo, Oscar

2014-12-02

Wireless Sensor Networks deliver valuable information for long periods, then it is desirable to have optimum performance, reduced delays, low overhead, and reliable delivery of information. In this work, proposed metrics that influence energy consumption are used for a performance comparison among our proposed routing protocol, called Multi-Parent Hierarchical (MPH), the well-known protocols for sensor networks, Ad hoc On-Demand Distance Vector (AODV), Dynamic Source Routing (DSR), and Zigbee Tree Routing (ZTR), all of them working with the IEEE 802.15.4 MAC layer. Results show how some communication metrics affect performance, throughput, reliability and energy consumption. It can be concluded that MPH is an efficient protocol since it reaches the best performance against the other three protocols under evaluation, such as 19.3% reduction of packet retransmissions, 26.9% decrease of overhead, and 41.2% improvement on the capacity of the protocol for recovering the topology from failures with respect to AODV protocol. We implemented and tested MPH in a real network of 99 nodes during ten days and analyzed parameters as number of hops, connectivity and delay, in order to validate our Sensors 2014, 14 22812 simulator and obtain reliable results. Moreover, an energy model of CC2530 chip is proposed and used for simulations of the four aforementioned protocols, showing that MPH has 15.9% reduction of energy consumption with respect to AODV, 13.7% versus DSR, and 5% against ZTR.

Computer Graphics: KidPix, the MacIntosh, and Students with Cognitive Disorders.

ERIC Educational Resources Information Center

Olson, Cindy

This teacher's guide provides an overview of KidPix software and contains adaptive applications of the software for Cognitively Disabled-Borderline (CDB) students. Ten lesson plans are given, including: (1) "USing Rubber Stamps/Rubber Stamp Editor"; (2) "Portrait"; (3) "Create a Pattern"; (4) "Garden Mural";…

Protocol for an Experiment on Controlling Motion Sickness Severity in a Ship Motion Simulator

DTIC Science & Technology

2004-10-01

MUN) School of Human Kinetics and Recreation, and Mr. Anthony Patterson and Mr. Carl Harris at the MUN Centre for Marine Simulation (CMS), for their...research contract with DRDC Atlantic. Dr. S.N. MacKinnon, Director of the Human Performance in Harsh Environments Laboratory, School of Human Kinetics and...MacKinnon, School of Human Kinetics and Recreation 737-8807 or smackinn@mun.ca DRDC Atlantic TM 2004-282 13 Annex B: Subject Consent Form

Modeling MAC layer for powerline communications networks

NASA Astrophysics Data System (ADS)

Hrasnica, Halid; Haidine, Abdelfatteh

2001-02-01

The usage of electrical power distribution networks for voice and data transmission, called Powerline Communications, becomes nowadays more and more attractive, particularly in the telecommunication access area. The most important reasons for that are the deregulation of the telecommunication market and a fact that the access networks are still property of former monopolistic companies. In this work, first we analyze a PLC network and system structure as well as a disturbance scenario in powerline networks. After that, we define a logical structure of the powerline MAC layer and propose the reservation MAC protocols for the usage in the PLC network which provides collision free data transmission. This makes possible better network utilization and realization of QoS guarantees which can make PLC networks competitive to other access technologies.

106-17 Telemetry Standards Chapter 7 Packet Telemetry Downlink

DTIC Science & Technology

2017-07-31

Acronyms IP Internet Protocol IPv4 Internet Protocol, Version 4 IPv6 Internet Protocol, Version 6 LLP low-latency PTDP MAC media access control...o 4’b0101: PT Internet Protocol (IP) Packet o 4’b0110: PT Chapter 24 TmNSMessage Packet o 4’b0111 – 4’b1111: Reserved • Fragment (bits 17 – 16...packet is defined as a free -running 12-bit counter. The PT test counter packet shall consist of one 12-bit word and shall be encoded as one 24-bit

Bandwidth Management in Resource Constrained Networks

DTIC Science & Technology

2012-03-01

Postgraduate School OSI Open Systems Interconnection QoS Quality of Service TCP Transmission Control Protocol/Internet Protocol TCP/IP Transmission...filtering. B. NORMAL TCP/IP COMMUNICATIONS The Internet is a “complex network WAN that connects LANs and clients around the globe” (Dean, 2009...of the Open Systems Interconnection ( OSI ) model allowing them to route traffic based on MAC address (Kurose & Ross, 2009). While switching

A low power medium access control protocol for wireless medical sensor networks.

PubMed

Lamprinos, I; Prentza, A; Sakka, E; Koutsouris, D

2004-01-01

The concept of a wireless integrated network of sensors, already applied in several sectors of our everyday life, such as security, transportation and environment monitoring, can as well provide an advanced monitor and control resource for healthcare services. By networking medical sensors wirelessly, attaching them in patient's body, we create the appropriate infrastructure for continuous and real-time monitoring of patient without discomforting him. This infrastructure can improve healthcare by providing the means for flexible acquisition of vital signs, while at the same time it provides more convenience to the patient. Given the type of wireless network, traditional medium access control (MAC) protocols cannot take advantage of the application specific requirements and information characteristics occurring in medical sensor networks, such as the demand for low power consumption and the rather limited and asymmetric data traffic. In this paper, we present the architecture of a low power MAC protocol, designated to support wireless networks of medical sensors. This protocol aims to improve energy efficiency by exploiting the inherent application features and requirements. It is oriented towards the avoidance of main energy wastage sources, such as idle listening, collision and power outspending.

A Low-Cost and Energy-Efficient Multiprocessor System-on-Chip for UWB MAC Layer

NASA Astrophysics Data System (ADS)

Xiao, Hao; Isshiki, Tsuyoshi; Khan, Arif Ullah; Li, Dongju; Kunieda, Hiroaki; Nakase, Yuko; Kimura, Sadahiro

Ultra-wideband (UWB) technology has attracted much attention recently due to its high data rate and low emission power. Its media access control (MAC) protocol, WiMedia MAC, promises a lot of facilities for high-speed and high-quality wireless communication. However, these benefits in turn involve a large amount of computational load, which challenges the traditional uniprocessor architecture based implementation method to provide the required performance. However, the constrained cost and power budget, on the other hand, makes using commercial multiprocessor solutions unrealistic. In this paper, a low-cost and energy-efficient multiprocessor system-on-chip (MPSoC), which tackles at once the aspects of system design, software migration and hardware architecture, is presented for the implementation of UWB MAC layer. Experimental results show that the proposed MPSoC, based on four simple RISC processors and shared-memory infrastructure, achieves up to 45% performance improvement and 65% power saving, but takes 15% less area than the uniprocessor implementation.

Chronic upregulation of activated microglia immunoreactive for galectin-3/Mac-2 and nerve growth factor following diffuse axonal injury

PubMed Central

2010-01-01

Background Diffuse axonal injury in patients with traumatic brain injury (TBI) can be associated with morbidity ranging from cognitive difficulties to coma. Magnetic resonance imaging scans now allow early detection of axonal injury following TBI, and have linked cognitive disability in these patients to white matter signal changes. However, little is known about the pathophysiology of this white matter injury, and the role of microglial activation in this process. It is increasingly recognized that microglia constitute a heterogeneous population with diverse roles following injury. In the present studies, we tested the hypothesis that following diffuse axonal injury involving the corpus callosum, there is upregulation of a subpopulation of microglia that express the lectin galectin-3/Mac-2 and are involved in myelin phagocytosis. Methods Adult mice were subject to midline closed skull injury or sham operation and were sacrificed 1, 8, 14 or 28 days later. Immunohistochemistry and immunofluorescence techniques were used to analyze patterns of labelling within the corpus callosum qualitatively and quantitatively. Results Activated microglia immunoreactive for galectin-3/Mac-2 were most abundant 1 day following injury. Their levels were attenuated at later time points after TBI but still were significantly elevated compared to sham animals. Furthermore, the majority of galectin-3/Mac-2+ microglia were immunoreactive for nerve growth factor in both sham and injured animals. Conclusions Our results suggest that galectin-3/Mac-2+ microglia play an important role in the pathogenesis of diffuse axonal injury both acutely and chronically and that they mediate their effects, at least in part by releasing nerve growth factor. PMID:20507613

Decisional Capacity for Research Participation in Individuals with Mild Cognitive Impairment

PubMed Central

Jefferson, Angela L.; Lambe, Susan; Moser, David J.; Byerly, Laura K.; Ozonoff, Al; Karlawish, Jason H.

2009-01-01

OBJECTIVES To assess decisional capacity performance and the neuropsychological correlates of such performance to better understand higher-level instrumental activities of daily living in individuals with mild cognitive impairment (MCI). DESIGN Cross-sectional. SETTING Research center, medical center, or patient’s home. PARTICIPANTS Forty participants with MCI and 40 cognitively normal older controls (NCs) aged 60 to 90 (mean age ± standard deviation 73.3 ± 6.6; 54% female). MEASUREMENTS Capacity to provide informed consent for a hypothetical, but ecologically valid, clinical trial was assessed using the MacArthur Competence Assessment Tool for Clinical Research. Neuropsychological functioning was assessed using a comprehensive protocol. RESULTS Adjusted between-group comparisons yielded significant differences for most decisional capacity indices examined, including Understanding (P = .001; NC>MCI) and Reasoning (P = .002; NC>MCI). Post hoc analyses revealed that participants with MCI who were categorized as capable of providing informed consent according to expert raters had higher levels of education than those who were categorized as incapable. CONCLUSION The findings suggest that many individuals with MCI perform differently on a measure of decisional capacity than their NC peers and that participants with MCI who are incapable of providing informed consent on a hypothetical and complex clinical trial are less educated. These findings are consistent with prior studies documenting functional and financial skill difficulties in individuals with MCI. PMID:18482298

Parental Family Stress during Pregnancy and Cognitive Functioning in Early Childhood: The Generation R Study

ERIC Educational Resources Information Center

Henrichs, Jens; Schenk, Jacqueline J.; Kok, Rianne; Ftitache, Bouchra; Schmidt, Henk G.; Hofman, Albert; Jaddoe, Vincent W. V.; Verhulst, Frank C.; Tiemeier, Henning

2011-01-01

We investigated whether parental family stress during pregnancy is associated with cognitive functioning in early childhood in a population-based cohort (n = 3139). Family stress was assessed using the Family Assessment Device at the 20th week of pregnancy and was reported by mothers and fathers. Mothers completed the MacArthur Communicative…

ECS: efficient communication scheduling for underwater sensor networks.

PubMed

Hong, Lu; Hong, Feng; Guo, Zhongwen; Li, Zhengbao

2011-01-01

TDMA protocols have attracted a lot of attention for underwater acoustic sensor networks (UWSNs), because of the unique characteristics of acoustic signal propagation such as great energy consumption in transmission, long propagation delay and long communication range. Previous TDMA protocols all allocated transmission time to nodes based on discrete time slots. This paper proposes an efficient continuous time scheduling TDMA protocol (ECS) for UWSNs, including the continuous time based and sender oriented conflict analysis model, the transmission moment allocation algorithm and the distributed topology maintenance algorithm. Simulation results confirm that ECS improves network throughput by 20% on average, compared to existing MAC protocols.

Ultra Low Power Signal Oriented Approach for Wireless Health Monitoring

PubMed Central

Marinkovic, Stevan; Popovici, Emanuel

2012-01-01

In recent years there is growing pressure on the medical sector to reduce costs while maintaining or even improving the quality of care. A potential solution to this problem is real time and/or remote patient monitoring by using mobile devices. To achieve this, medical sensors with wireless communication, computational and energy harvesting capabilities are networked on, or in, the human body forming what is commonly called a Wireless Body Area Network (WBAN). We present the implementation of a novel Wake Up Receiver (WUR) in the context of standardised wireless protocols, in a signal-oriented WBAN environment and present a novel protocol intended for wireless health monitoring (WhMAC). WhMAC is a TDMA-based protocol with very low power consumption. It utilises WBAN-specific features and a novel ultra low power wake up receiver technology, to achieve flexible and at the same time very low power wireless data transfer of physiological signals. As the main application is in the medical domain, or personal health monitoring, the protocol caters for different types of medical sensors. We define four sensor modes, in which the sensors can transmit data, depending on the sensor type and emergency level. A full power dissipation model is provided for the protocol, with individual hardware and application parameters. Finally, an example application shows the reduction in the power consumption for different data monitoring scenarios. PMID:22969379

Ultra low power signal oriented approach for wireless health monitoring.

PubMed

Marinkovic, Stevan; Popovici, Emanuel

2012-01-01

In recent years there is growing pressure on the medical sector to reduce costs while maintaining or even improving the quality of care. A potential solution to this problem is real time and/or remote patient monitoring by using mobile devices. To achieve this, medical sensors with wireless communication, computational and energy harvesting capabilities are networked on, or in, the human body forming what is commonly called a Wireless Body Area Network (WBAN). We present the implementation of a novel Wake Up Receiver (WUR) in the context of standardised wireless protocols, in a signal-oriented WBAN environment and present a novel protocol intended for wireless health monitoring (WhMAC). WhMAC is a TDMA-based protocol with very low power consumption. It utilises WBAN-specific features and a novel ultra low power wake up receiver technology, to achieve flexible and at the same time very low power wireless data transfer of physiological signals. As the main application is in the medical domain, or personal health monitoring, the protocol caters for different types of medical sensors. We define four sensor modes, in which the sensors can transmit data, depending on the sensor type and emergency level. A full power dissipation model is provided for the protocol, with individual hardware and application parameters. Finally, an example application shows the reduction in the power consumption for different data monitoring scenarios.

Differences in quantitative methods for measuring subjective cognitive decline - results from a prospective memory clinic study.

PubMed

Vogel, Asmus; Salem, Lise Cronberg; Andersen, Birgitte Bo; Waldemar, Gunhild

2016-09-01

Cognitive complaints occur frequently in elderly people and may be a risk factor for dementia and cognitive decline. Results from studies on subjective cognitive decline are difficult to compare due to variability in assessment methods, and little is known about how different methods influence reports of cognitive decline. The Subjective Memory Complaints Scale (SMC) and The Memory Complaint Questionnaire (MAC-Q) were applied in 121 mixed memory clinic patients with mild cognitive symptoms (mean MMSE = 26.8, SD 2.7). The scales were applied independently and raters were blinded to results from the other scale. Scales were not used for diagnostic classification. Cognitive performances and depressive symptoms were also rated. We studied the association between the two measures and investigated the scales' relation to depressive symptoms, age, and cognitive status. SMC and MAC-Q were significantly associated (r = 0.44, N = 121, p = 0.015) and both scales had a wide range of scores. In this mixed cohort of patients, younger age was associated with higher SMC scores. There were no significant correlations between cognitive test performances and scales measuring subjective decline. Depression scores were significantly correlated to both scales measuring subjective decline. Linear regression models showed that age did not have a significant contribution to the variance in subjective memory beyond that of depressive symptoms. Measures for subjective cognitive decline are not interchangeable when used in memory clinics and the application of different scales in previous studies is an important factor as to why studies show variability in the association between subjective cognitive decline and background data and/or clinical results. Careful consideration should be taken as to which questions are relevant and have validity when operationalizing subjective cognitive decline.

On Proper Selection of Multihop Relays for Future Enhancement of AeroMACS Networks

NASA Technical Reports Server (NTRS)

Kamali, Behnam; Kerczewski, Robert J.; Apaza, Rafael D.

2015-01-01

As the Aeronautical Mobile Airport Communications System (AeroMACS) has evolved from a technology concept to a deployed communications network over major US airports, it is now time to contemplate whether the existing capacity of AeroMACS is sufficient to meet the demands set forth by all fixed and mobile applications over the airport surface given the AeroMACS constraints regarding bandwidth and transmit power. The underlying idea in this article is to present IEEE 802.16j-based WiMAX as a technology that can address future capacity enhancements and therefore is most feasible for AeroMACS applications. The principal argument in favor IEEE 802.16j technology is the flexible and cost effective extension of radio coverage that is afforded by relay fortified networks, with virtually no increase in the power requirements and virtually no rise in interference levels to co-allocated applications. The IEEE 802.16j-based multihop relay systems are briefly described. The focus is on key features of this technology, frame structure, and its architecture. Next, AeroMACS is described as a WiMAX-based wireless network. The two major relay modes supported by IEEE 802.16j amendment, i.e., transparent and non-transparent are described. The benefits of employing multihop relays are listed. Some key challenges related to incorporating relays into AeroMACS networks are discussed. The selection of relay type in a broadband wireless network affects a number of network parameters such as latency, signal overhead, PHY (Scalable Physical Layer) and MAC (Media Access Layer) layer protocols, consequently it can alter key network quantities of throughput and QoS (Quality of Service).

Integrated multi-channel vehicle-vehicle and vehicle-roadside communications for ITS

DOT National Transportation Integrated Search

2008-12-01

This research describes a medium access control (MAC) protocol to Enable multi-channel operation for dedicated short-range communication (DSRC). In particular, we focus on the challenge of supporting potentially high-bandwidth commercial or infotainm...

Assessing capacity to consent for research in cognitively impaired older patients

PubMed Central

Gilbert, Thomas; Bosquet, Antoine; Thomas-Antérion, Catherine; Bonnefoy, Marc; Le Saux, Olivia

2017-01-01

Background The number of clinical trials including older patients, and particularly patients with cognitive impairment, is increasing. While statutory provisions exist to make sure that the capacity to consent is assessed systematically for each patient, many gray areas remain with regard to how this assessment is made or should be made in the routine practice of clinical research. Objectives The aim of this review was to draw up an inventory of assessment tools evaluating older patients’ capacity to consent specifically applicable to clinical research, which could be used in routine practice. Methods Two authors independently searched PubMed, Cochrane, and Google Scholar data-bases between November 2015 and January 2016. The search was actualized in April 2017. We used keywords (MeSH terms and text words) referring to informed consent, capacity to consent, consent for research, research ethics, cognitive impairment, vulnerable older patients, and assessment tools. Existing reviews were also considered. Results Among the numerous existing tools for assessing capacity to consent, 14 seemed potentially suited for clinical research and six were evaluated in older patients. The MacArthur Competence Assessment Tool for Clinical Research (MacCAT-CR) was the most frequently cited. Conclusion The MacCAT-CR is currently the most used and the best validated questionnaire. However, it appears difficult to use and time-consuming. A more recent tool, the University of California Brief Assessment of Capacity to Consent (UBACC), seems interesting for routine practice because of its simplicity, relevance, and applicability in older patients. PMID:29026293

Mixed membership trajectory models of cognitive impairment in the multicenter AIDS cohort study.

PubMed

Molsberry, Samantha A; Lecci, Fabrizio; Kingsley, Lawrence; Junker, Brian; Reynolds, Sandra; Goodkin, Karl; Levine, Andrew J; Martin, Eileen; Miller, Eric N; Munro, Cynthia A; Ragin, Ann; Sacktor, Ned; Becker, James T

2015-03-27

The longitudinal trajectories that individuals may take from a state of normal cognition to HIV-associated dementia are unknown. We applied a novel statistical methodology to identify trajectories to cognitive impairment, and factors that affected the 'closeness' of an individual to one of the canonical trajectories. The Multicenter AIDS Cohort Study (MACS) is a four-site longitudinal study of the natural and treated history of HIV disease among gay and bisexual men. Using data from 3892 men (both HIV-infected and HIV-uninfected) enrolled in the neuropsychology substudy of the MACS, a Mixed Membership Trajectory Model (MMTM) was applied to capture the pathways from normal cognitive function to mild impairment to severe impairment. MMTMs allow the data to identify canonical pathways and to model the effects of risk factors on an individual's 'closeness' to these trajectories. First, we identified three distinct trajectories to cognitive impairment: 'normal aging' (low probability of mild impairment until age 60); 'premature aging' (mild impairment starting at age 45-50); and 'unhealthy' (mild impairment in 20s and 30s) profiles. Second, clinically defined AIDS, and not simply HIV disease, was associated with closeness to the premature aging trajectory, and, third, hepatitis-C infection, depression, race, recruitment cohort and confounding conditions all affected individual's closeness to these trajectories. These results provide new insight into the natural history of cognitive dysfunction in HIV disease and provide evidence for a potential difference in the pathophysiology of the development of cognitive impairment based on trajectories to impairment.

Addictive personality factors.

PubMed

Kagan, D M

1987-11-01

This study was designed to compare mean scores obtained by alcoholics, compulsive gamblers, smokers, chronic joggers, and control subjects on six subfactors of the MacAndrew Alcoholism Scale. Results indicated that some MacAndrew factors may be more sensitive to additive pathology than others. Alcoholics emerged as the most pathological group, in terms of scores on the Cognitive Impairment, Social Maladjustment, and Risk Taking scales. Gamblers and smokers appeared to be distinctly different, more socially oriented addicts. Frequency of jogging was negatively related to measures of addiction but positively related to measures of compulsiveness.

ECS: Efficient Communication Scheduling for Underwater Sensor Networks

PubMed Central

Hong, Lu; Hong, Feng; Guo, Zhongwen; Li, Zhengbao

2011-01-01

TDMA protocols have attracted a lot of attention for underwater acoustic sensor networks (UWSNs), because of the unique characteristics of acoustic signal propagation such as great energy consumption in transmission, long propagation delay and long communication range. Previous TDMA protocols all allocated transmission time to nodes based on discrete time slots. This paper proposes an efficient continuous time scheduling TDMA protocol (ECS) for UWSNs, including the continuous time based and sender oriented conflict analysis model, the transmission moment allocation algorithm and the distributed topology maintenance algorithm. Simulation results confirm that ECS improves network throughput by 20% on average, compared to existing MAC protocols. PMID:22163775

Effects of group metacognitive training (MCT) on mental capacity and functioning in patients with psychosis in a secure forensic psychiatric hospital: a prospective-cohort waiting list controlled study.

PubMed

Naughton, Marie; Nulty, Andrea; Abidin, Zareena; Davoren, Mary; O'Dwyer, Sarah; Kennedy, Harry G

2012-06-18

Metacognitive Training (MCT) is a manualised cognitive intervention for psychosis aimed at transferring knowledge of cognitive biases and providing corrective experiences. The aim of MCT is to facilitate symptom reduction and protect against relapse. In a naturalistic audit of clinical effectiveness we examined what effect group MCT has on mental capacity, symptoms of psychosis and global function in patients with a psychotic illness, when compared with a waiting list comparison group. Of 93 patients detained in a forensic mental health hospital under both forensic and civil mental health legislation, 19 were assessed as suitable for MCT and 11 commenced. These were compared with 8 waiting list patients also deemed suitable for group MCT who did not receive it in the study timeframe. The PANSS, GAF, MacArthur Competence Assessment Tool- Treatment (MacCAT-T) and MacArthur Competence Assessment Tool-Fitness to Plead (MacCAT-FP) were recorded at baseline and repeated after group MCT or following treatment as usual in the waiting list group. When baseline functioning was accounted for, patients that attended MCT improved in capacity to consent to treatment as assessed by the MacCAT-T (p = 0.019). The more sessions attended, the greater the improvements in capacity to consent to treatment, mainly due to improvement in MacCAT-T understanding (p = 0.014) and reasoning . The GAF score improved in patients who attended the MCT group when compared to the waiting list group (p = 0.038) but there were no changes in PANSS scores. Measures of functional mental capacity and global function can be used as outcome measures for MCT. MCT can be used successfully even in psychotic patients detained in a forensic setting. The restoration of elements of decision making capacity such as understanding and reasoning may be a hither-to unrecognised advantage of such treatment. Because pharmacotherapy can be optimised and there is likely to be enough time to complete the course, there are clear opportunities to benefit from such treatment programmes in forensic settings.

Effects of group metacognitive training (MCT) on mental capacity and functioning in patients with psychosis in a secure forensic psychiatric hospital: a prospective-cohort waiting list controlled study

PubMed Central

2012-01-01

Background Metacognitive Training (MCT) is a manualised cognitive intervention for psychosis aimed at transferring knowledge of cognitive biases and providing corrective experiences. The aim of MCT is to facilitate symptom reduction and protect against relapse. In a naturalistic audit of clinical effectiveness we examined what effect group MCT has on mental capacity, symptoms of psychosis and global function in patients with a psychotic illness, when compared with a waiting list comparison group. Methods Of 93 patients detained in a forensic mental health hospital under both forensic and civil mental health legislation, 19 were assessed as suitable for MCT and 11 commenced. These were compared with 8 waiting list patients also deemed suitable for group MCT who did not receive it in the study timeframe. The PANSS, GAF, MacArthur Competence Assessment Tool- Treatment (MacCAT-T) and MacArthur Competence Assessment Tool-Fitness to Plead (MacCAT-FP) were recorded at baseline and repeated after group MCT or following treatment as usual in the waiting list group. Results When baseline functioning was accounted for, patients that attended MCT improved in capacity to consent to treatment as assessed by the MacCAT-T (p = 0.019). The more sessions attended, the greater the improvements in capacity to consent to treatment, mainly due to improvement in MacCAT-T understanding (p = 0.014) and reasoning . The GAF score improved in patients who attended the MCT group when compared to the waiting list group (p = 0.038) but there were no changes in PANSS scores. Conclusion Measures of functional mental capacity and global function can be used as outcome measures for MCT. MCT can be used successfully even in psychotic patients detained in a forensic setting. The restoration of elements of decision making capacity such as understanding and reasoning may be a hither-to unrecognised advantage of such treatment. Because pharmacotherapy can be optimised and there is likely to be enough time to complete the course, there are clear opportunities to benefit from such treatment programmes in forensic settings. PMID:22709616

Enhancement of Beaconless Location-Based Routing with Signal Strength Assistance for Ad-Hoc Networks

NASA Astrophysics Data System (ADS)

Chen, Guowei; Itoh, Kenichi; Sato, Takuro

Routing in Ad-hoc networks is unreliable due to the mobility of the nodes. Location-based routing protocols, unlike other protocols which rely on flooding, excel in network scalability. Furthermore, new location-based routing protocols, like, e. g. BLR [1], IGF [2], & CBF [3] have been proposed, with the feature of not requiring beacons in MAC-layer, which improve more in terms of scalability. Such beaconless routing protocols can work efficiently in dense network areas. However, these protocols' algorithms have no ability to avoid from routing into sparse areas. In this article, historical signal strength has been added as a factor into the BLR algorithm, which avoids routing into sparse area, and consequently improves the global routing efficiency.

Mutually Augmented Cognition

NASA Astrophysics Data System (ADS)

Friesdorf, Florian; Pangercic, Dejan; Bubb, Heiner; Beetz, Michael

In mac, an ergonomic dialog-system and algorithms will be developed that enable human experts and companions to be integrated into knowledge gathering and decision making processes of highly complex cognitive systems (e.g. Assistive Household as manifested further in the paper). In this event we propose to join algorithms and methodologies coming from Ergonomics and Artificial Intelligence that: a) make cognitive systems more congenial for non-expert humans, b) facilitate their comprehension by utilizing a high-level expandable control code for human experts and c) augment representation of such cognitive system into “deep representation” obtained through an interaction with human companions.

Advanced Shipboard Control Systems

DTIC Science & Technology

2001-05-07

Nov 1989: 41-47. Carnivale, J. A. DD-21 Presentation. Jan 1999. Deitel H.M. and P. J. Deitel . C++ How To Program . Upper Saddle River...One distinct advantage to an OSI model is that each level of the network is clearly defined, allowing different users to understand how a specific...Pri) field that tells the layer how this message is to be sent. The L2Hdr is an 8 bit section of the Link Protocol Data Unit/MAC Protocol Data

Cross-Layer Protocol Combining Tree Routing and TDMA Slotting in Wireless Sensor Networks

NASA Astrophysics Data System (ADS)

Bai, Ronggang; Ji, Yusheng; Lin, Zhiting; Wang, Qinghua; Zhou, Xiaofang; Qu, Yugui; Zhao, Baohua

Being different from other networks, the load and direction of data traffic for wireless sensor networks are rather predictable. The relationships between nodes are cooperative rather than competitive. These features allow the design approach of a protocol stack to be able to use the cross-layer interactive way instead of a hierarchical structure. The proposed cross-layer protocol CLWSN optimizes the channel allocation in the MAC layer using the information from the routing tables, reduces the conflicting set, and improves the throughput. Simulations revealed that it outperforms SMAC and MINA in terms of delay and energy consumption.

Neuropsychological phenotypes among men with and without HIV disease in the multicenter AIDS cohort study.

PubMed

Molsberry, Samantha A; Cheng, Yu; Kingsley, Lawrence; Jacobson, Lisa; Levine, Andrew J; Martin, Eileen; Miller, Eric N; Munro, Cynthia A; Ragin, Ann; Sacktor, Ned; Becker, James T

2018-05-11

Mild forms of HIV-associated neurocognitive disorder (HAND) remain prevalent in the combination anti-retroviral therapy (cART) era. This study's objective was to identify neuropsychological subgroups within the Multicenter AIDS Cohort Study (MACS) based on the participant-based latent structure of cognitive function and to identify factors associated with subgroups. The MACS is a four-site longitudinal study of the natural and treated history of HIV disease among gay and bisexual men. Using neuropsychological domain scores we used a cluster variable selection algorithm to identify the optimal subset of domains with cluster information. Latent profile analysis was applied using scores from identified domains. Exploratory and post-hoc analyses were conducted to identify factors associated with cluster membership and the drivers of the observed associations. Cluster variable selection identified all domains as containing cluster information except for Working Memory. A three-profile solution produced the best fit for the data. Profile 1 performed below average on all domains, Profile 2 performed average on executive functioning, motor, and speed and below average on learning and memory, Profile 3 performed at or above average across all domains. Several demographic, cognitive, and social factors were associated with profile membership; these associations were driven by differences between Profile 1 and the other profiles. There is an identifiable pattern of neuropsychological performance among MACS members determined by all domains except Working Memory. Neither HIV nor HIV-related biomarkers were related with cluster membership, consistent with other findings that cognitive performance patterns do not map directly onto HIV serostatus.

Cross-Layer Algorithms for QoS Enhancement in Wireless Multimedia Sensor Networks

NASA Astrophysics Data System (ADS)

Saxena, Navrati; Roy, Abhishek; Shin, Jitae

A lot of emerging applications like advanced telemedicine and surveillance systems, demand sensors to deliver multimedia content with precise level of QoS enhancement. Minimizing energy in sensor networks has been a much explored research area but guaranteeing QoS over sensor networks still remains an open issue. In this letter we propose a cross-layer approach combining Network and MAC layers, for QoS enhancement in wireless multimedia sensor networks. In the network layer a statistical estimate of sensory QoS parameters is performed and a nearoptimal genetic algorithmic solution is proposed to solve the NP-complete QoS-routing problem. On the other hand the objective of the proposed MAC algorithm is to perform the QoS-based packet classification and automatic adaptation of the contention window. Simulation results demonstrate that the proposed protocol is capable of providing lower delay and better throughput, at the cost of reasonable energy consumption, in comparison with other existing sensory QoS protocols.

Designing of routing algorithms in autonomous distributed data transmission system for mobile computing devices with ‘WiFi-Direct’ technology

NASA Astrophysics Data System (ADS)

Nikitin, I. A.; Sherstnev, V. S.; Sherstneva, A. I.; Botygin, I. A.

2017-02-01

The results of the research of existent routing protocols in wireless networks and their main features are discussed in the paper. Basing on the protocol data, the routing protocols in wireless networks, including search routing algorithms and phone directory exchange algorithms, are designed with the ‘WiFi-Direct’ technology. Algorithms without IP-protocol were designed, and that enabled one to increase the efficiency of the algorithms while working only with the MAC-addresses of the devices. The developed algorithms are expected to be used in the mobile software engineering with the Android platform taken as base. Easier algorithms and formats of the well-known route protocols, rejection of the IP-protocols enables to use the developed protocols on more primitive mobile devices. Implementation of the protocols to the engineering industry enables to create data transmission networks among working places and mobile robots without any access points.

The research and application of the NDP protocol vulnerability attack and the defense technology based on SEND

NASA Astrophysics Data System (ADS)

Xi, Huixing

2017-05-01

Neighbor discovery protocol (NDP) is the underlying protocol in the IPv6 protocol, which is mainly used to solve the problem of interconnection between nodes on the same link. But with wide use of IPV6, NDP becomes the main objects of a variety of attacks due to a lack of security mechanism. The paper introduces the working principle of the NDP and methods of how the SEND protocol to enhance NDP security defense. It also analyzes and summarizes the security threats caused by the defects of the protocol itself. On the basis of the SEND protocol, the NDP data packet structure is modified to enhance the security of the SEND. An improved NDP cheating defense technology is put forward to make up the defects of the SEND protocol which can't verify the correctness of the public key and cannot bind the MAC address.

A survey of system architecture requirements for health care-based wireless sensor networks.

PubMed

Egbogah, Emeka E; Fapojuwo, Abraham O

2011-01-01

Wireless Sensor Networks (WSNs) have emerged as a viable technology for a vast number of applications, including health care applications. To best support these health care applications, WSN technology can be adopted for the design of practical Health Care WSNs (HCWSNs) that support the key system architecture requirements of reliable communication, node mobility support, multicast technology, energy efficiency, and the timely delivery of data. Work in the literature mostly focuses on the physical design of the HCWSNs (e.g., wearable sensors, in vivo embedded sensors, et cetera). However, work towards enhancing the communication layers (i.e., routing, medium access control, et cetera) to improve HCWSN performance is largely lacking. In this paper, the information gleaned from an extensive literature survey is shared in an effort to fortify the knowledge base for the communication aspect of HCWSNs. We highlight the major currently existing prototype HCWSNs and also provide the details of their routing protocol characteristics. We also explore the current state of the art in medium access control (MAC) protocols for WSNs, for the purpose of seeking an energy efficient solution that is robust to mobility and delivers data in a timely fashion. Furthermore, we review a number of reliable transport layer protocols, including a network coding based protocol from the literature, that are potentially suitable for delivering end-to-end reliability of data transmitted in HCWSNs. We identify the advantages and disadvantages of the reviewed MAC, routing, and transport layer protocols as they pertain to the design and implementation of a HCWSN. The findings from this literature survey will serve as a useful foundation for designing a reliable HCWSN and also contribute to the development and evaluation of protocols for improving the performance of future HCWSNs. Open issues that required further investigations are highlighted.

Optimizing the MAC Protocol in Localization Systems Based on IEEE 802.15.4 Networks

PubMed Central

Claver, Jose M.; Ezpeleta, Santiago

2017-01-01

Radio frequency signals are commonly used in the development of indoor localization systems. The infrastructure of these systems includes some beacons placed at known positions that exchange radio packets with users to be located. When the system is implemented using wireless sensor networks, the wireless transceivers integrated in the network motes are usually based on the IEEE 802.15.4 standard. But, the CSMA-CA, which is the basis for the medium access protocols in this category of communication systems, is not suitable when several users want to exchange bursts of radio packets with the same beacon to acquire the radio signal strength indicator (RSSI) values needed in the location process. Therefore, new protocols are necessary to avoid the packet collisions that appear when multiple users try to communicate with the same beacons. On the other hand, the RSSI sampling process should be carried out very quickly because some systems cannot tolerate a large delay in the location process. This is even more important when the RSSI sampling process includes measures with different signal power levels or frequency channels. The principal objective of this work is to speed up the RSSI sampling process in indoor localization systems. To achieve this objective, the main contribution is the proposal of a new MAC protocol that eliminates the medium access contention periods and decreases the number of packet collisions to accelerate the RSSI collection process. Moreover, the protocol increases the overall network throughput taking advantage of the frequency channel diversity. The presented results show the suitability of this protocol for reducing the RSSI gathering delay and increasing the network throughput in simulated and real environments. PMID:28684666

Optimizing the MAC Protocol in Localization Systems Based on IEEE 802.15.4 Networks.

PubMed

Pérez-Solano, Juan J; Claver, Jose M; Ezpeleta, Santiago

2017-07-06

Radio frequency signals are commonly used in the development of indoor localization systems. The infrastructure of these systems includes some beacons placed at known positions that exchange radio packets with users to be located. When the system is implemented using wireless sensor networks, the wireless transceivers integrated in the network motes are usually based on the IEEE 802.15.4 standard. But, the CSMA-CA, which is the basis for the medium access protocols in this category of communication systems, is not suitable when several users want to exchange bursts of radio packets with the same beacon to acquire the radio signal strength indicator (RSSI) values needed in the location process. Therefore, new protocols are necessary to avoid the packet collisions that appear when multiple users try to communicate with the same beacons. On the other hand, the RSSI sampling process should be carried out very quickly because some systems cannot tolerate a large delay in the location process. This is even more important when the RSSI sampling process includes measures with different signal power levels or frequency channels. The principal objective of this work is to speed up the RSSI sampling process in indoor localization systems. To achieve this objective, the main contribution is the proposal of a new MAC protocol that eliminates the medium access contention periods and decreases the number of packet collisions to accelerate the RSSI collection process. Moreover, the protocol increases the overall network throughput taking advantage of the frequency channel diversity. The presented results show the suitability of this protocol for reducing the RSSI gathering delay and increasing the network throughput in simulated and real environments.

Vehicle Density Based Forwarding Protocol for Safety Message Broadcast in VANET

PubMed Central

Huang, Jiawei; Wang, Jianxin

2014-01-01

In vehicular ad hoc networks (VANETs), the medium access control (MAC) protocol is of great importance to provide time-critical safety applications. Contemporary multihop broadcast protocols in VANETs usually choose the farthest node in broadcast range as the forwarder to reduce the number of forwarding hops. However, in this paper, we demonstrate that the farthest forwarder may experience large contention delay in case of high vehicle density. We propose an IEEE 802.11-based multihop broadcast protocol VDF to address the issue of emergency message dissemination. To achieve the tradeoff between contention delay and forwarding hops, VDF adaptably chooses the forwarder according to the vehicle density. Simulation results show that, due to its ability to decrease the transmission collisions, the proposed protocol can provide significantly lower broadcast delay. PMID:25121125

Attentional Retraining Administered to Cigarette Smokers in the Field: Effects on Attentional Bias, Craving, and Smoking

DTIC Science & Technology

2013-08-30

in cognitive bias modification was originally stimulated by the work of MacLeod, Mathews, and colleagues in their studies of the cognitive processes...probe would always replace the neutral stimulus which may not necessarily have occurred without these instructions). This may have stimulated the...retrain auditory or even olfactory attention. An important first step in this process would be the exploration of possible attentional biases for

Using Cortically-Inspired Algorithms for Analogical Learning and Reasoning

DTIC Science & Technology

2013-01-01

similar to the theory described by Piaget (1954). While chunk only finds conjunctions, some of the percep- tual models listed above do ‘‘pooling’’ (finding...Law, K. (1995). MAC/FAC: A model of similarity-based retrieval. Cognitive Science, 19. Gayler, R., & Levy, S . (2009). A distributed basis for...abstraction using structure mapping. In Proceedings of the 22nd annual meeting of the cognitive science society. Langley, P., Laird, J. E., & Rogers, S

Montreal Cognitive Assessment 5-minute protocol is a brief, valid, reliable, and feasible cognitive screen for telephone administration.

PubMed

Wong, Adrian; Nyenhuis, David; Black, Sandra E; Law, Lorraine S N; Lo, Eugene S K; Kwan, Pauline W L; Au, Lisa; Chan, Anne Y Y; Wong, Lawrence K S; Nasreddine, Ziad; Mok, Vincent

2015-04-01

The National Institute of Neurological Disorders and Stroke-Canadian Stroke Network Vascular Cognitive Impairment Harmonization working group proposed a brief cognitive protocol for screening of vascular cognitive impairment. We investigated the validity, reliability, and feasibility of the Montreal Cognitive Assessment 5-minute protocol (MoCA 5-minute protocol) administered over the telephone. Four items examining attention, verbal learning and memory, executive functions/language, and orientation were extracted from the MoCA to form the MoCA 5-minute protocol. One hundred four patients with stroke or transient ischemic attack, including 53 with normal cognition (Clinical Dementia Rating, 0) and 51 with cognitive impairment (Clinical Dementia Rating, 0.5 or 1), were administered the MoCA in clinic and a month later, the MoCA 5-minute protocol over the telephone. Administration of the MoCA 5-minute protocol took 5 minutes over the telephone. Total score of the MoCA 5-minute protocol correlated negatively with age (r=-0.36; P<0.001) and positively with years of education (r=0.41; P<0.001) but not with sex (ρ=0.03; P=0.773). Total scores of the MoCA and MoCA 5-minute protocol were highly correlated (r=0.87; P<0.001). The MoCA 5-minute protocol performed equally well as the MoCA in differentiating patients with cognitive impairment from those without (areas under receiver operating characteristics curve for MoCA 5-minute protocol, 0.78; MoCA=0.74; P>0.05 for difference; Cohen d for group difference, 0.80-1.13). It differentiated cognitively impaired patients with executive domain impairment from those without (areas under receiver operating characteristics curve, 0.89; P<0.001; Cohen d=1.7 for group difference). Thirty-day test-retest reliability was excellent (intraclass correlation coefficient, 0.89). The MoCA 5-minute protocol is a free, valid, and reliable cognitive screen for stroke and transient ischemic attack. It is brief and highly feasible for telephone administration. © 2015 American Heart Association, Inc.

Cognitive Protocol Stack Design

DTIC Science & Technology

2015-12-30

SECURITY CLASSIFICATION OF: In the ARO “ Cognitive Protocol Stack Design" project we proposed cognitive networking solutions published in international...areas related to cognitive networking, opening also new lines of research that was not possible to forecast at the beginning of the project. In a...Distribution Unlimited Final Report: Cognitive Protocol Stack Design The views, opinions and/or findings contained in this report are those of the author(s

Intranasally delivered small interfering RNA-mediated suppression of scavenger receptor Mac-1 attenuates microglial phenotype switching and working memory impairment following hypoxia.

PubMed

Das, Sudeshna; Mishra, K P; Ganju, Lilly; Singh, S B

2018-05-05

Brain, being the highest consumer of oxygen, is prone to increased risk of hypoxia-induced neurological insults. In response to hypoxia, microglia, the major resident immune cells of brain switches to an activated phenotype and promote inflammatory responses leading to tissue damage and loss of cognitive functions including working memory impairment. Till date, no proven clinical therapeutics is available to retard the progression of neurodegenerative memory impairment. In the present study, we investigated the therapeutic potential of intranasal small interfering RNA (siRNA) delivery in a mouse model of hypoxia-induced working memory impairment using microglial receptor, Mac-1 as a target gene. Here, we implicate Mac-1 scavenger receptor in microglial phenotype switching, neurodegeneration in prefrontal cortex, hippocampus and working memory impairment. RNA mediated silencing of Mac-1 in both in vitro and in vivo model showed significant impact of it on hypoxia induced altered expression of Mac-1 endogenous ligand, signaling cascade proteins, transcription factors and NADPH oxidase pathway. Efficient degradation of Mac-1 mRNA suppressed expression of M1 phenotypic markers, inflammatory chemokines, and cytokines, but on the other hand, it upregulated M2 phenotypic markers and anti-inflammatory cytokines. Neuronal viability and synaptic plasticity markers were also modulated significantly by this strategy. Behavioral study revealed significant downregulation in the number of working memory errors at a time-dependent manner after silencing the Mac-1 gene during continuous hypoxic exposure. The novel findings of this study for the very first time, unmasked the role of Mac-1 receptor in neurodegenerative disease progression under hypoxic condition and at the same time indicated the potential therapeutic value of this non-invasive siRNA delivery approach for treating working memory loss. Copyright © 2018 Elsevier Ltd. All rights reserved.

Psychopathology, psychopharmacological properties, decision-making capacity to consent to clinical research and the willingness to participate among long-term hospitalized patients with schizophrenia.

PubMed

Wu, Bo-Jian; Liao, Hsun-Yi; Chen, Hsing-Kang; Lan, Tsuo-Hung

2016-03-30

Many studies discuss factors related to the decision-making capacity to consent to clinical research (DMC) of patients with schizophrenia. However, these studies rarely approached willingness to participate and the association between psychopharmacological properties (e.g., antipsychotic-induced side effects) and DMC. This study aimed to explore factors related to DMC and willingness to participate in patients with schizophrenia. All 139 patients with schizophrenia were assessed with the MacArthur Competence Assessment Tool for Clinical Research (MacCAT-CR) and other measures. A linear regression model was used to find the predictors of MacCAT-CR scores. A logistic regression model was used for exploring the predictors of willingness to participate. Patients with more severe negative symptoms performed poorly in DMC outcomes. In addition, females, those with fewer years of education and reduced cognitive function are more likely to experience difficulties in decision-making. Forty-three subjects (30.4%) chose to participate. Patients with higher level of positive symptoms, longer length of stay, higher burden of anticholinergics and users of atypical antipsychotics were more likely to participate in a clinical study which aimed to "enhance cognition". These finding suggest that research investigators should consider many variables for patients who require more intensive screening for impaired DMC. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Using the memory activation capture (MAC) procedure to investigate the temporal dynamics of hypothesis generation.

PubMed

Lange, Nicholas D; Buttaccio, Daniel R; Davelaar, Eddy J; Thomas, Rick P

2014-02-01

Research investigating top-down capture has demonstrated a coupling of working memory content with attention and eye movements. By capitalizing on this relationship, we have developed a novel methodology, called the memory activation capture (MAC) procedure, for measuring the dynamics of working memory content supporting complex cognitive tasks (e.g., decision making, problem solving). The MAC procedure employs briefly presented visual arrays containing task-relevant information at critical points in a task. By observing which items are preferentially fixated, we gain a measure of working memory content as the task evolves through time. The efficacy of the MAC procedure was demonstrated in a dynamic hypothesis generation task in which some of its advantages over existing methods for measuring changes in the contents of working memory over time are highlighted. In two experiments, the MAC procedure was able to detect the hypothesis that was retrieved and placed into working memory. Moreover, the results from Experiment 2 suggest a two-stage process following hypothesis retrieval, whereby the hypothesis undergoes a brief period of heightened activation before entering a lower activation state in which it is maintained for output. The results of both experiments are of additional general interest, as they represent the first demonstrations of top-down capture driven by participant-established WM content retrieved from long-term memory.

[Perspectives on patient competence in psychiatry: cognitive functions, emotions and values].

PubMed

Ruissen, A; Meynen, G; Widdershoven, G A M

2011-01-01

Informed consent, a central concept in the doctor-patient relationship, is only valid if it is given by a competent patient. To review the literature on competence or decision-making capacity in psychiatry. We studied the international literature and relevant Dutch material such as health acts and medical guidelines. We found a consensus in the literature about the assessment criteria and the basic principles, but we did not find any consensus about the exact definition of competence. We review a number of perspectives on competence. The conceptualisations of competence, particularly in the field of psychiatry, are still being debated. The best known clinical tool to assess patients’ capacities to make treatment decisions is the MacArthur Competence Assessment Tool (MacCAT). There are three perspectives on competence: a cognitive perspective, a perspective concerning emotions and a perspective relating to values. Further research is needed in order to make the conceptual debate on competence relevant to psychiatric practice.

Ravens, New Caledonian crows and jackdaws parallel great apes in motor self-regulation despite smaller brains.

PubMed

Kabadayi, Can; Taylor, Lucy A; von Bayern, Auguste M P; Osvath, Mathias

2016-04-01

Overriding motor impulses instigated by salient perceptual stimuli represent a fundamental inhibitory skill. Such motor self-regulation facilitates more rational behaviour, as it brings economy into the bodily interaction with the physical and social world. It also underlies certain complex cognitive processes including decision making. Recently, MacLean et al. (MacLean et al. 2014 Proc. Natl Acad. Sci. USA 111, 2140-2148. (doi:10.1073/pnas.1323533111)) conducted a large-scale study involving 36 species, comparing motor self-regulation across taxa. They concluded that absolute brain size predicts level of performance. The great apes were most successful. Only a few of the species tested were birds. Given birds' small brain size-in absolute terms-yet flexible behaviour, their motor self-regulation calls for closer study. Corvids exhibit some of the largest relative avian brain sizes-although small in absolute measure-as well as the most flexible cognition in the animal kingdom. We therefore tested ravens, New Caledonian crows and jackdaws in the so-called cylinder task. We found performance indistinguishable from that of great apes despite the much smaller brains. We found both absolute and relative brain volume to be a reliable predictor of performance within Aves. The complex cognition of corvids is often likened to that of great apes; our results show further that they share similar fundamental cognitive mechanisms.

Adaptive Code Division Multiple Access Protocol for Wireless Network-on-Chip Architectures

NASA Astrophysics Data System (ADS)

Vijayakumaran, Vineeth

Massive levels of integration following Moore's Law ushered in a paradigm shift in the way on-chip interconnections were designed. With higher and higher number of cores on the same die traditional bus based interconnections are no longer a scalable communication infrastructure. On-chip networks were proposed enabled a scalable plug-and-play mechanism for interconnecting hundreds of cores on the same chip. Wired interconnects between the cores in a traditional Network-on-Chip (NoC) system, becomes a bottleneck with increase in the number of cores thereby increasing the latency and energy to transmit signals over them. Hence, there has been many alternative emerging interconnect technologies proposed, namely, 3D, photonic and multi-band RF interconnects. Although they provide better connectivity, higher speed and higher bandwidth compared to wired interconnects; they also face challenges with heat dissipation and manufacturing difficulties. On-chip wireless interconnects is one other alternative proposed which doesn't need physical interconnection layout as data travels over the wireless medium. They are integrated into a hybrid NOC architecture consisting of both wired and wireless links, which provides higher bandwidth, lower latency, lesser area overhead and reduced energy dissipation in communication. However, as the bandwidth of the wireless channels is limited, an efficient media access control (MAC) scheme is required to enhance the utilization of the available bandwidth. This thesis proposes using a multiple access mechanism such as Code Division Multiple Access (CDMA) to enable multiple transmitter-receiver pairs to send data over the wireless channel simultaneously. It will be shown that such a hybrid wireless NoC with an efficient CDMA based MAC protocol can significantly increase the performance of the system while lowering the energy dissipation in data transfer. In this work it is shown that the wireless NoC with the proposed CDMA based MAC protocol outperformed the wired counterparts and several other wireless architectures proposed in literature in terms of bandwidth and packet energy dissipation. Significant gains were observed in packet energy dissipation and bandwidth even with scaling the system to higher number of cores. Non-uniform traffic simulations showed that the proposed CDMA-WiNoC was consistent in bandwidth across all traffic patterns. It is also shown that the CDMA based MAC scheme does not introduce additional reliability concerns in data transfer over the on-chip wireless interconnects.

French multicenter study involving eight test sites for radiometric determination of activities of 10 antimicrobial agents against Mycobacterium avium complex.

PubMed Central

Rastogi, N; Bauriaud, R M; Bourgoin, A; Carbonnelle, B; Chippaux, C; Gevaudan, M J; Goh, K S; Moinard, D; Roos, P

1995-01-01

The radiometric BACTEC 460-TB methodology has filled an increased need in the screening of a wide range of antimicrobial agents against Mycobacterium avium (MAC) isolates on a patient-to-patient basis. In this context, a multicenter study involving eight test sites across France was performed to determine the MICs of 10 antimicrobial agents for MAC organisms. The aim of the investigation was to compare the in vitro activities of D-cycloserine, ethambutol, ethionamide, rifampin, amikacin, streptomycin, ciprofloxacin, sparfloxacin, clofazimine, and clarithromycin against MAC isolates. All of the test sites received the same clinical isolates of MAC, and the MICs were determined by a common protocol. The overall interlaboratory reproducibility of the MICs within +/- 1 dilution of the modal MICs varied from 79.70 to 100% (mean, 95.2% +/- 2.1%), whereas overall agreement of the MICs among the test sites varied from a mean of 91% +/- 4.1% to a mean of 98 +/- 1.3%. We confirmed that the proposed methodology is easy, accurate, and sufficiently reproducible to be used routinely in a clinical laboratory. Despite variations in the MICs of the same drug among strains, no link between the origin of MAC isolates (from human immunodeficiency virus-positive or -negative patients) and their drug susceptibilities was established. On the basis of the MICs that inhibited 50 and 90% of isolates tested for the drugs used, clarithromycin, clofazimine, ethambutol, and streptomycin were the most uniformly active against MAC; this was followed by amikacin, rifampin, and sparfloxacin. On the other hand, ciprofloxacin, D-cycloserine, and ethionamide showed only marginal in vitro activities. PMID:7793865

Detomidine reduces isoflurane anesthetic requirement (MAC) in horses.

PubMed

Steffey, Eugene P; Pascoe, Peter J

2002-10-01

To quantitate the dose- and time-related magnitude of the anesthetic sparing effect of, and selected physiological responses to detomidine during isoflurane anesthesia in horses. Randomized cross-over study. Three, healthy, young adult horses weighing 485 ± 14 kg. Horses were anesthetized on two occasions to determine the minimum alveolar concentration (MAC) of isoflurane in O 2 and then to measure the anesthetic sparing effect (time-related MAC reduction) following IV detomidine (0.03 and 0.06 mg kg -1 ). Selected common measures of cardiopulmonary function, blood glucose and urinary output were also recorded. Isoflurane MAC was 1.44 ± 0.07% (mean ± SEM). This was reduced by 42.8 ± 5.4% and 44.8 ± 3.0% at 83 ± 23 and 125 ± 36 minutes, respectively, following 0.03 and 0.06 mg kg -1 , detomidine. The MAC reduction was detomidine dose- and time-dependent. There was a tendency for mild cardiovascular and respiratory depression, especially following the higher detomidine dose. Detomidine increased both blood glucose and urine flow; the magnitude of these changes was time- and dose-dependent CONCLUSIONS: Detomidine reduces anesthetic requirement for isoflurane and increases blood glucose concentration and urine flow in horses. These changes were dose- and time-related. The results imply potent anesthetic sparing actions by detomidine. The detomidine-related increased urine flow should be considered in designing anesthetic protocols for individual horses. Copyright © 2002 Association of Veterinary Anaesthetists and American College of Veterinary Anesthesia and Analgesia. Published by Elsevier Ltd. All rights reserved.

Magnetic-Activated Cell Sorting for the Fast and Efficient Separation of Human and Rodent Schwann Cells from Mixed Cell Populations.

PubMed

Ravelo, Kristine M; Andersen, Natalia D; Monje, Paula V

2018-01-01

To date, magnetic-activated cell sorting (MACS) remains a powerful method to isolate distinct cell populations based on differential cell surface labeling. Optimized direct and indirect MACS protocols for cell immunolabeling are presented here as methods to divest Schwann cell (SC) cultures of contaminating cells (specifically, fibroblast cells) and isolate SC populations at different stages of differentiation. This chapter describes (1) the preparation of single-cell suspensions from established human and rat SC cultures, (2) the design and application of cell selection strategies using SC-specific (p75 NGFR , O4, and O1) and fibroblast-specific (Thy-1) markers, and (3) the characterization of both the pre- and post-sorting cell populations. A simple protocol for the growth of hybridoma cell cultures as a source of monoclonal antibodies for cell surface immunolabeling of SCs and fibroblasts is provided as a cost-effective alternative for commercially available products. These steps allow for the timely and efficient recovery of purified SC populations without compromising the viability and biological activity of the cells.

A MAC Protocol to Support Monitoring of Underwater Spaces.

PubMed

Santos, Rodrigo; Orozco, Javier; Ochoa, Sergio F; Meseguer, Roc; Eggly, Gabriel; Pistonesi, Marcelo F

2016-06-27

Underwater sensor networks are becoming an important field of research, because of their everyday increasing application scope. Examples of their application areas are environmental and pollution monitoring (mainly oil spills), oceanographic data collection, support for submarine geolocalization, ocean sampling and early tsunamis alert. The challenge of performing underwater communications is well known, provided that radio signals are useless in this medium, and a wired solution is too expensive. Therefore, the sensors in these networks transmit their information using acoustic signals that propagate well under water. This data transmission type not only brings an opportunity, but also several challenges to the implementation of these networks, e.g., in terms of energy consumption, data transmission and signal interference. In order to help advance the knowledge in the design and implementation of these networks for monitoring underwater spaces, this paper proposes a MAC protocol for acoustic communications between the nodes, based on a self-organized time division multiple access mechanism. The proposal was evaluated using simulations of a real monitoring scenario, and the obtained results are highly encouraging.

Mental capacity in patients involuntarily or voluntarily receiving psychiatric treatment for an acute mental disorder.

PubMed

Mandarelli, Gabriele; Tarsitani, Lorenzo; Parmigiani, Giovanna; Polselli, Gian M; Frati, Paola; Biondi, Massimo; Ferracuti, Stefano

2014-07-01

Despite the growing amount of data, much information is needed on patients' mental capacity to consent to psychiatric treatment for acute mental disorders. The present study was undertaken to compare differences in capacity to consent to psychiatric treatment in patients treated voluntarily and involuntarily and to investigate the role of psychiatric symptoms, competency, and cognitive functioning in determining voluntariness of hospital admission. Involuntary patients were interviewed with the MacArthur Competence Assessment Tool for Treatment (MacCAT-T), the 24-item Brief Psychiatric Rating Scale (BPRS), the Mini Mental State Examination (MMSE) and the Raven's Colored Progressive Matrices, and their data were compared with those for age- and sex-matched voluntary patients. Involuntary patients performed worse in all MacCAT-T subscales. Capacity to consent to treatment varied widely within each group. Overall, involuntary patients have worse consent-related mental capacity than those treated voluntarily, despite capacity to consent to treatment showing a significant variability in both groups. © 2014 American Academy of Forensic Sciences.

Twelve-Week Exercise Influences Memory Complaint but not Memory Performance in Older Adults: A Randomized Controlled Study.

PubMed

Iuliano, Enzo; Fiorilli, Giovanni; Aquino, Giovanna; Di Costanzo, Alfonso; Calcagno, Giuseppe; di Cagno, Alessandra

2017-10-01

This study aimed to evaluate the effects of different types of exercise on memory performance and memory complaint after a 12-week intervention. Eighty community-dwelling volunteers, aged 66.96 ± 11.73 years, were randomly divided into four groups: resistance, cardiovascular, postural, and control groups (20 participants for each group). All participants were tested for their cognitive functions before and after their respective 12-week intervention using Rey memory words test, Prose memory test, and Memory Complaint Questionnaire (MAC-Q). Statistical analysis showed that the three experimental groups significantly improved MAC-Q scores in comparison with the control group (p < .05). The variation of MAC-Q scores and the variations of Rey and Prose memory tests scores were not correlated. These results indicate that the 12-week interventions exclusively influenced memory complaint but not memory performance. Further investigations are needed to understand the relation between memory complaint and memory performance, and the factors that can influence this relationship.

CENet: A Cabinet Environmental Sensing Network

PubMed Central

Zhang, Zusheng; Yu, Fengqi; Chen, Liang; Cao, Guangmin

2010-01-01

For data center cooling and intelligent substation systems, real time cabinet environmental monitoring is a strong requirement. Monitoring data, such as temperature, humidity, and noise, is important for operators to manage the facilities in cabinets. We here propose a sensing network, called CENet, which is energy efficient and reliable for cabinet environmental monitoring. CENet achieves above 93% reliable data yield and sends fewer beacons compared to periodic beaconing. It does so through a data-aided routing protocol. In addition, based on B-MAC, we propose a scheduling scheme to increase the lifetime of the network by reducing unnecessary message snooping and channel listening, thus it is more energy efficient than B-MAC. The performance of CENet is evaluated by simulations and experiments. PMID:22205856

[Methodical problems of monitoring of fine particulate matters in atmospheric air of residential areas].

PubMed

Karelin, A O; Lomtev, A Yu; Mozzhukhina, N A; Yeremin, G B; Nikonov, V A

Inhalation of fine particulate matters (PM and PM ) poses a threat for the health of population. Purpose of the study the analysis of the monitoring of fine particulate matters in the atmospheric air of Saint-Petersburg and identification of the main problems of the monitoring. Research methods methods of scientific hypothetical deductive cognition, sanitary-statistical methods, general logical methods and approaches of researches: analysis, synthesis, abstracting, generalization, induction. Results. The article represents the analysis of the monitoring of fine particulate matters in the atmospheric air of Saint- Petersburg. Only 11 in automatic monitoring stations out of 22 there is carried out the control of fine particulate matters: in 7 - PM and PM, and in 4 - PM The average year concentrations were below MAC in all the stations. The maximum concentrations achieved 3 MAC, but the repeatance of cases of exceedence of concentrations more than MAC was very rare. On the average of the city concentrations of PM were decreased from 0,8 MAC in 2006 and 1,1 MAC in 2007 to 0,5 MAC in 2013-14. The executed analysis revealed main problems of the monitoring of fine particulate matters in the Russian Federation. They include the absence of the usage 1of the officially approved methods of controlling of PM and PM in the atmospheric air until March 1, 2016, lack of the modern equipment for measurement of fine particulate matters. Conclusions. Therefore, the state of the monitoring of fine particulate matters in the atmospheric air in the Russian Federation fails to be satisfactory. It is necessary to improve system of the monitoring, create modern Russian appliances, methods and means for measurement of fine particulate matters concentrations in the atmospheric air.

Effectiveness of AODV Protocol under Hidden Node Environment

NASA Astrophysics Data System (ADS)

Garg, Ruchi; Sharma, Himanshu; Kumar, Sumit

IEEE 802.11 is a standard for mobile ad hoc networks (MANET), implemented with various different protocols. Ad Hoc on Demand Distance Vector Routing (AODV) is one of the several protocols of IEEE 802.11, intended to provide various Quality of Service (QOS) parameters under acceptable range. To avoid the collision and interference the MAC protocol has only two solutions, one, to sense the physical carrier and second, to use the RTS/CTS handshake mechanism. But with the help of these methods AODV is not free from the problem of hidden nodes like other several protocols. Under the hidden node environment, performance of AODV depends upon various factors. The position of receiver and sender among the other nodes is very crucial and it affects the performance. Under the various situations the AODV is simulated with the help of NS2 and the outcomes are discussed.

Medical Patients’ Treatment Decision Making Capacity: A Report from a General Hospital in Greece

PubMed Central

Bilanakis, Nikolaos; Vratsista, Aikaterini; Athanasiou, Eleni; Niakas, Dimitris; Peritogiannis, Vaios

2014-01-01

This study aimed to assess the decision-making capacity for treatment of patients hospitalized in an internal medicine ward of a General Hospital in Greece, and to examine the views of treating physicians regarding patients’ capacity. All consecutive admissions to an internal medicine ward within a month were evaluated. A total of 134 patients were approached and 78 patients were interviewed with the MacArthur Competence Assessment Tool for Treatment (MacCAT-T) and the Mini Mental State Examination (MMSE) questionnaire. Sixty-eight out of 134 patients (50.7%) were incompetent to decide upon their treatment. The majority of them (n=56, 41.8%) were obviously incapable because they were unconscious, or had such marked impairment that they could not give their own names, and the rest (n=12, 8.9%) were rated as incompetent according to their performance in the MacCAT-T. Neurological disorders, old age and altered cognitive function according to MMSE were negatively correlated with decision making capacity. Physicians sometimes failed to recognize patients’ incapacity. Rates of decision-making incapacity for treatment in medical inpatients are high, and incapacity may go unrecognized by treating physicians. Combined patient evaluation with the use of the MacCAT-T and MMSE, could be useful for the determination of incapable patients. PMID:25505489

The Mental Activity and eXercise (MAX) trial: a randomized controlled trial to enhance cognitive function in older adults.

PubMed

Barnes, Deborah E; Santos-Modesitt, Wendy; Poelke, Gina; Kramer, Arthur F; Castro, Cynthia; Middleton, Laura E; Yaffe, Kristine

2013-05-13

The prevalence of cognitive impairment and dementia are projected to rise dramatically during the next 40 years, and strategies for maintaining cognitive function with age are critically needed. Physical or mental activity alone result in relatively small, domain-specific improvements in cognitive function in older adults; combined interventions may have more global effects. To examine the combined effects of physical plus mental activity on cognitive function in older adults. Randomized controlled trial with a factorial design. San Francisco, California. A total of 126 inactive, community-residing older adults with cognitive complaints. All participants engaged in home-based mental activity (1 h/d, 3 d/wk) plus class-based physical activity (1 h/d, 3 d/wk) for 12 weeks and were randomized to either mental activity intervention (MA-I; intensive computer) or mental activity control (MA-C; educational DVDs) plus exercise intervention (EX-I; aerobic) or exercise control (EX-C; stretching and toning); a 2 × 2 factorial design was used so that there were 4 groups: MA-I/EX-I, MA-I/EX-C, MA-C/EX-1, and MA-C/EX-C. Global cognitive change based on a comprehensive neuropsychological test battery. Participants had a mean age of 73.4 years; 62.7% were women, and 34.9% were Hispanic or nonwhite. There were no significant differences between the groups at baseline. Global cognitive scores improved significantly over time (mean, 0.16 SD; P < .001) but did not differ between groups in the comparison between MA-I and MA-C (ignoring exercise, P = .17), the comparison between EX-I and EX-C (ignoring mental activity, P = .74), or across all 4 randomization groups (P = .26). In inactive older adults with cognitive complaints, 12 weeks of physical plus mental activity was associated with significant improvements in global cognitive function with no evidence of difference between intervention and active control groups. These findings may reflect practice effects or may suggest that the amount of activity is more important than the type in this subject population. clinicaltrials.gov Identifier: NCT00522899.

Iberian Spanish "Macho": Vantages and Polysemy in Culturally Defined Meaning

ERIC Educational Resources Information Center

Grace, Caroline A.; Glaz, Adam

2010-01-01

This study explores some specific aspects of compatibility between cognitive models. Robert E. MacLaury's theory of vantages as arrangements of coordinates and Lakoff's concept of radial categories are mutually reinforcing to an analysis of semantic polysemy. Vantage Theory (VT) includes the notions of "zooming in" and "zooming out", allowing…

The Relationship between Teacher Efficacy and Reading Program Type in West Virginia Elementary Schools

ERIC Educational Resources Information Center

Harvey, Patricia Lee

2009-01-01

This study, based on Bandura's social cognitive theory, explored the two dimensions of teacher efficacy among reading program types (Harcourt; Houghton Mifflin; MacMillan McGraw Hill; Pearson Scott Foresman; and, Other) and selected demographic factors (school enrollment size; student ethnicity; school district of urban, rural, and suburban;…

An adaptive density-based routing protocol for flying Ad Hoc networks

NASA Astrophysics Data System (ADS)

Zheng, Xueli; Qi, Qian; Wang, Qingwen; Li, Yongqiang

2017-10-01

An Adaptive Density-based Routing Protocol (ADRP) for Flying Ad Hoc Networks (FANETs) is proposed in this paper. The main objective is to calculate forwarding probability adaptively in order to increase the efficiency of forwarding in FANETs. ADRP dynamically fine-tunes the rebroadcasting probability of a node for routing request packets according to the number of neighbour nodes. Indeed, it is more interesting to privilege the retransmission by nodes with little neighbour nodes. We describe the protocol, implement it and evaluate its performance using NS-2 network simulator. Simulation results reveal that ADRP achieves better performance in terms of the packet delivery fraction, average end-to-end delay, normalized routing load, normalized MAC load and throughput, which is respectively compared with AODV.

The impact of a science-based integrated instructional protocol on the motivation, reading comprehension, and science achievement of fourth and fifth graders

NASA Astrophysics Data System (ADS)

Stephens, Kathy E.

The purpose of this study was to determine the impact of implementing an integrated instructional protocol of science-based informational texts as teacher read alouds, student independent reading, and written journal responses on motivation, reading comprehension, and science achievement of fourth- and fifth-grade students with attention to specific student groups, including gender and ethnicities. A mixed methods research design included a 12-week intervention conducted with 68 fourth and fifth graders and 30 nonintervention fourth and fifth graders. Participating fourth and fifth graders completed the comprehension subtest of the Gates-MacGinitie Reading Test ([GMRT] MacGinitie, MacGinitie, Maria, & Dreyer, 2000) and the Texas Assessment of Knowledge and Skills ([TAKS] Texas Education Agency [TEA], 2005a). The Reading Survey of the Motivation to Read Profile ([MRP], Gambrell, Palmer, Codling, & Mazzoni, 1996) served as another quantitative data source. Qualitative data sources included classroom observations, key informant interviews, and student journal entries. The GMRT results indicated that the intervention fourth graders demonstrated the largest growth in reading comprehension achievement. Significant differences were noted by GMRT results between the intervention and nonintervention fourth graders. A significant difference was found between fourth-grade males and females on the GMRT, with a larger gain posted by the females. No significant differences were found on the GMRT in fifth grade Reading TAKS results indicated a significant difference between intervention fourth-grade Hispanic and African American students, while fifth-grade Science TAKS results indicated no significant differences. The MRP Reading Survey results indicated no significant differences; however, fourth-grade Hispanic and fifth-grade male students demonstrated significant growth. Classroom observations documented the progress of the 12-week intervention; 9 primary instructional and behavioral themes with 40 subcategories were discovered using open coding (Berg, 2004). Data were collected from the MRP Conversational Interview (Gambrell et al., 1996) with 12 key informants, and their journal entries provided evidence of the impact of the instructional protocol. Findings from this study seemed to confirm that students may experience improvement in reading comprehension after participation in an integrated instructional protocol. Findings also suggested gaps in minority ethnicities may be minimized, while female students continued to outscore male students.

Implicit Block ACK Scheme for IEEE 802.11 WLANs

PubMed Central

Sthapit, Pranesh; Pyun, Jae-Young

2016-01-01

The throughput of IEEE 802.11 standard is significantly bounded by the associated Medium Access Control (MAC) overhead. Because of the overhead, an upper limit exists for throughput, which is bounded, including situations where data rates are extremely high. Therefore, an overhead reduction is necessary to achieve higher throughput. The IEEE 802.11e amendment introduced the block ACK mechanism, to reduce the number of control messages in MAC. Although the block ACK scheme greatly reduces overhead, further improvements are possible. In this letter, we propose an implicit block ACK method that further reduces the overhead associated with IEEE 802.11e’s block ACK scheme. The mathematical analysis results are presented for both the original protocol and the proposed scheme. A performance improvement of greater than 10% was achieved with the proposed implementation.

On the Design of a Comprehensive Authorisation Framework for Service Oriented Architecture (SOA)

DTIC Science & Technology

2013-07-01

Authentication Server AZM Authorisation Manager AZS Authorisation Server BP Business Process BPAA Business Process Authorisation Architecture BPAD Business...Internet Protocol Security JAAS Java Authentication and Authorisation Service MAC Mandatory Access Control RBAC Role Based Access Control RCA Regional...the authentication process, make authorisation decisions using application specific access control functions that results in the practice of

Adjacency Matrix-Based Transmit Power Allocation Strategies in Wireless Sensor Networks

PubMed Central

Consolini, Luca; Medagliani, Paolo; Ferrari, Gianluigi

2009-01-01

In this paper, we present an innovative transmit power control scheme, based on optimization theory, for wireless sensor networks (WSNs) which use carrier sense multiple access (CSMA) with collision avoidance (CA) as medium access control (MAC) protocol. In particular, we focus on schemes where several remote nodes send data directly to a common access point (AP). Under the assumption of finite overall network transmit power and low traffic load, we derive the optimal transmit power allocation strategy that minimizes the packet error rate (PER) at the AP. This approach is based on modeling the CSMA/CA MAC protocol through a finite state machine and takes into account the network adjacency matrix, depending on the transmit power distribution and determining the network connectivity. It will be then shown that the transmit power allocation problem reduces to a convex constrained minimization problem. Our results show that, under the assumption of low traffic load, the power allocation strategy, which guarantees minimal delay, requires the maximization of network connectivity, which can be equivalently interpreted as the maximization of the number of non-zero entries of the adjacency matrix. The obtained theoretical results are confirmed by simulations for unslotted Zigbee WSNs. PMID:22346705

Development of Cognitive Bias Modification (CBM) Tools to Promote Adjustment during Reintegration following Deployment

DTIC Science & Technology

2017-06-01

Abnormal Psychology , 95, 15– 20. doi:10.1037//0021-843x.95.1.15 MacLeod, C., Rutherford, E., Campbell, L., Ebsworthy, G., & Holker, L. (2002). Selective...of Abnormal Psychology , 111, 107–123. doi:10.1037//0021-843x. 111.1.107 Mammen, O. K., Pilkonis, P. A., & Kolko, D. J. (2000). Anger and parent-to...cognitive basis of trait anger and reactive aggression: An integrative analysis. Personality and Social Psychology Review, 12(1), 3–21. doi:10. 1177

Retinal Crystals in Type 2 Idiopathic Macular Telangiectasia

PubMed Central

Sallo, Ferenc B; Leung, Irene; Chung, Mina; Wolf-Schnurrbusch, Ute EK; Dubra, Alfredo; Williams, David R; Clemons, Traci; Pauleikhoff, Daniel; Bird, Alan C; Peto, Tunde

2012-01-01

Purpose To characterize the phenotype and investigate the associations of intraretinal crystalline deposits in a large cohort of Type 2 Idiopathic Macular Telangiectasia (MacTel) Design Case-control study Participants Patients with and without retinal crystals from the Macular Telangiectasia Project, an international multi-centre prospective study of Type 2 MacTel. Methods Grading of stereoscopic 30° colour fundus (CF), confocal blue light reflectance (CBR), red-free (RF) and infrared (IR) images was performed according to the MacTel Natural History Study protocol and staged using the classification system devised by Gass & Blodi. SD-OCT and adaptive optics imaging were used for a finer analysis of the phenotype. Associations between crystals and other characteristics of the disease as well as potential risk factors were investigated. Main outcome measures Presence of crystals, fundus signs of MacTel, clinical characteristics, presence of potential risk factors of MacTel. Results Out of 443 probands enrolled in the MacTel study, 203 (46%) had crystalline deposits present; 60% of the cases were bilateral at baseline. Eyes with crystals had a mean letter score of 70.7 (SD=15.9) while those without crystals had a mean of 66.5 letters (SD=15.5, p<0.001). Crystals were present at all stages of the disease and showed high reflectivity within a wide wavelength range. They were located at the anterior surface of the nerve fibre layer, arranged along the nerve fibres, within an annular area centred on the fovea. Significant associations of crystalline deposits were found with a loss of retinal transparency, MPOD loss, fluorescein leakage, retinal thickness and a break in the IS/OS junction line. Associations with environmental risk factors were not found. Conclusions Intraretinal crystals are a frequent phenomenon associated with type 2 MacTel, they may appear at all stages and may aid in the early diagnosis of the disease. Their morphology further implicates Müller cells in the pathogenesis of the disease. Insight into their physical and chemical properties may provide clues to the metabolic pathways involved in the pathogenesis of the disease. PMID:21839520

Improved biovolume estimation of Microcystis aeruginosa colonies: A statistical approach.

PubMed

Alcántara, I; Piccini, C; Segura, A M; Deus, S; González, C; Martínez de la Escalera, G; Kruk, C

2018-05-27

The Microcystis aeruginosa complex (MAC) clusters many of the most common freshwater and brackish bloom-forming cyanobacteria. In monitoring protocols, biovolume estimation is a common approach to determine MAC colonies biomass and useful for prediction purposes. Biovolume (μm 3 mL -1 ) is calculated multiplying organism abundance (orgL -1 ) by colonial volume (μm 3 org -1 ). Colonial volume is estimated based on geometric shapes and requires accurate measurements of dimensions using optical microscopy. A trade-off between easy-to-measure but low-accuracy simple shapes (e.g. sphere) and time costly but high-accuracy complex shapes (e.g. ellipsoid) volume estimation is posed. Overestimations effects in ecological studies and management decisions associated to harmful blooms are significant due to the large sizes of MAC colonies. In this work, we aimed to increase the precision of MAC biovolume estimations by developing a statistical model based on two easy-to-measure dimensions. We analyzed field data from a wide environmental gradient (800 km) spanning freshwater to estuarine and seawater. We measured length, width and depth from ca. 5700 colonies under an inverted microscope and estimated colonial volume using three different recommended geometrical shapes (sphere, prolate spheroid and ellipsoid). Because of the non-spherical shape of MAC the ellipsoid resulted in the most accurate approximation, whereas the sphere overestimated colonial volume (3-80) especially for large colonies (MLD higher than 300 μm). Ellipsoid requires measuring three dimensions and is time-consuming. Therefore, we constructed different statistical models to predict organisms depth based on length and width. Splitting the data into training (2/3) and test (1/3) sets, all models resulted in low training (1.41-1.44%) and testing average error (1.3-2.0%). The models were also evaluated using three other independent datasets. The multiple linear model was finally selected to calculate MAC volume as an ellipsoid based on length and width. This work contributes to achieve a better estimation of MAC volume applicable to monitoring programs as well as to ecological research. Copyright © 2017. Published by Elsevier B.V.

Pre- and postconditioning effect of Sevoflurane on myocardial dysfunction after cardiopulmonary resuscitation in rats.

PubMed

Knapp, Jürgen; Bergmann, Greta; Bruckner, Thomas; Russ, Nicolai; Böttiger, Bernd W; Popp, Erik

2013-10-01

Post-resuscitation myocardial dysfunction is an important cause of death in the intensive care unit after initially successful cardiopulmonary resuscitation (CPR) of pre-hospital cardiac arrest (CA) patients. Volatile anaesthetics reduce ischaemic-reperfusion injury in regional ischaemia in beating hearts. This effect, called anaesthetic-induced pre- or postconditioning, can be shown when the volatile anaesthetic is given either before regional ischaemia or in the reperfusion phase. However, up to now, little data exist for volatile anaesthetics after global ischaemia due to CA. Therefore, the goal of this study was to clarify whether Sevoflurane improves post-resuscitation myocardial dysfunction after CA in rats. Following institutional approval by the Governmental Animal Care Committee, 144 male Wistar rats (341±19g) were randomized either to a control group or to one of the 9 interventional groups receiving 0.25 MAC, 0.5 MAC or 1 MAC of Sevoflurane for 5min either before resuscitation (SBR), during resuscitation (SDR) or after resuscitation (SAR). After 6min of electrically induced ventricular fibrillation CPR was performed. Before CA (baseline) as well as 1h and 24h after restoration of spontaneous circulation (ROSC), continuous measurement of ejection fraction (EF), and preload adjusted maximum power (PAMP) as primary outcome parameters and end systolic pressure (ESP), end diastolic volume (EDV) and maximal slope of systolic pressure increment (dP/dtmax) as secondary outcome parameters was performed using a conductance catheter. EF was improved in all Sevoflurane treated groups 1h after ROSC in comparison to control, except for the 0.25 MAC SDR and 0.25 MAC SAR group (0.25 MAC SBR: 38±8, p=0.02; 0.5 MAC SBR: 39±7, p=0.04; 1 MAC SBR: 40±6, p=0.007; 0.5 MAC SDR: 38±7, p=0.02; 1 MAC SDR: 40±6, p=0.006; 0.5 MAC SAR: 39±6, p=0.01; 1 MAC SAR: 39±6, p=0.002, vs. 30±7%). Twenty-four hours after ROSC, EF was higher than control in all interventional groups (p<0.05 for all groups). EF recovered to baseline values 24h after ROSC in all SBR and SAR groups. PAMP was improved in comparison to control (4.6±3.0mW/μl(2)) 24h after ROSC in 0.5 MAC SBR (9.4±6.9mW/μl(2), p=0.04), 1 MAC SBR (8.9±4.4mW/μl(2), p=0.04), 1 MAC SDR (8.0±5.7mW/μl(2), p=0.04), and 1 MAC SAR (7.3±3.5mW/μl(2), p=0.04). ESP, EDV, and dP/dtmax was not different from control 1h as well as 24h after ROSC with the exception of 1 MAC SDR with a reduced ESP 1h after ROSC (89±16 vs. 103±22mmHg, p=0.04). Sevoflurane treatment did not affect survival rate. This animal study of CA and resuscitation provides the hypothesis that pharmacological pre- or postconditioning with the volatile anaesthetic Sevoflurane - administered before CA, during resuscitation or after ROSC - results in an improved myocardial inotropy 24h after ROSC. Sevoflurane treatment seems to improve EF even in the early phase of reperfusion 1h after ROSC. Therefore further targeted studies on the optimal dose and time point of administration of Sevoflurane in cardiopulmonary resuscitation seem to be worthwhile (Institutional protocol number: 35-9185.81/G-24/08). Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Monkey Prefrontal Neurons Reflect Logical Operations for Cognitive Control in a Variant of the AX Continuous Performance Task (AX-CPT)

PubMed Central

Blackman, Rachael K.; Crowe, David A.; DeNicola, Adele L.; Sakellaridi, Sofia; MacDonald, Angus W.

2016-01-01

Cognitive control is the ability to modify the behavioral response to a stimulus based on internal representations of goals or rules. We sought to characterize neural mechanisms in prefrontal cortex associated with cognitive control in a context that would maximize the potential for future translational relevance to human neuropsychiatric disease. To that end, we trained monkeys to perform a dot-pattern variant of the AX continuous performance task that is used to measure cognitive control impairment in patients with schizophrenia (MacDonald, 2008; Jones et al., 2010). Here we describe how information processing for cognitive control in this task is related to neural activity patterns in prefrontal cortex of monkeys, to advance our understanding of how behavioral flexibility is implemented by prefrontal neurons in general, and to model neural signals in the healthy brain that may be disrupted to produce cognitive control deficits in schizophrenia. We found that the neural representation of stimuli in prefrontal cortex is strongly biased toward stimuli that inhibit prepotent or automatic responses. We also found that population signals encoding different stimuli were modulated to overlap in time specifically in the case that information from multiple stimuli had to be integrated to select a conditional response. Finally, population signals relating to the motor response were biased toward less frequent and therefore less automatic actions. These data relate neuronal activity patterns in prefrontal cortex to logical information processing operations required for cognitive control, and they characterize neural events that may be disrupted in schizophrenia. SIGNIFICANCE STATEMENT Functional imaging studies have demonstrated that cognitive control deficits in schizophrenia are associated with reduced activation of the dorsolateral prefrontal cortex (MacDonald et al., 2005). However, these data do not reveal how the disease has disrupted the function of prefrontal neurons to produce the observed deficits in cognitive control. Relating cognitive control to neurophysiological signals at a cellular level in prefrontal cortex is a necessary first step toward understanding how disruption of these signals could lead to cognitive control failure in neuropsychiatric disease. To that end, we translated a task that measures cognitive control deficits in patients with schizophrenia to monkeys and describe here how neural signals in prefrontal cortex relate to performance. PMID:27053213

5G small-cell networks leveraging optical technologies with mm-wave massive MIMO and MT-MAC protocols

NASA Astrophysics Data System (ADS)

Papaioannou, S.; Kalfas, G.; Vagionas, C.; Mitsolidou, C.; Maniotis, P.; Miliou, A.; Pleros, N.

2018-01-01

Analog optical fronthaul for 5G network architectures is currently being promoted as a bandwidth- and energy-efficient technology that can sustain the data-rate, latency and energy requirements of the emerging 5G era. This paper deals with a new optical fronthaul architecture that can effectively synergize optical transceiver, optical add/drop multiplexer and optical beamforming integrated photonics towards a DSP-assisted analog fronthaul for seamless and medium-transparent 5G small-cell networks. Its main application targets include dense and Hot-Spot Area networks, promoting the deployment of mmWave massive MIMO Remote Radio Heads (RRHs) that can offer wireless data-rates ranging from 25Gbps up to 400Gbps depending on the fronthaul technology employed. Small-cell access and resource allocation is ensured via a Medium-Transparent (MT-) MAC protocol that enables the transparent communication between the Central Office and the wireless end-users or the lamp-posts via roof-top-located V-band massive MIMO RRHs. The MTMAC is analysed in detail with simulation and analytical theoretical results being in good agreement and confirming its credentials to satisfy 5G network latency requirements by guaranteeing latency values lower than 1 ms for small- to midload conditions. Its extension towards supporting optical beamforming capabilities and mmWave massive MIMO antennas is discussed, while its performance is analysed for different fiber fronthaul link lengths and different optical channel capacities. Finally, different physical layer network architectures supporting the MT-MAC scheme are presented and adapted to different 5G use case scenarios, starting from PON-overlaid fronthaul solutions and gradually moving through Spatial Division Multiplexing up to Wavelength Division Multiplexing transport as the user density increases.

A Robust and Energy-Efficient Transport Protocol for Cognitive Radio Sensor Networks

PubMed Central

Salim, Shelly; Moh, Sangman

2014-01-01

A cognitive radio sensor network (CRSN) is a wireless sensor network in which sensor nodes are equipped with cognitive radio. CRSNs benefit from cognitive radio capabilities such as dynamic spectrum access and transmission parameters reconfigurability; but cognitive radio also brings additional challenges and leads to higher energy consumption. Motivated to improve the energy efficiency in CRSNs, we propose a robust and energy-efficient transport protocol (RETP). The novelties of RETP are two-fold: (I) it combines distributed channel sensing and channel decision with centralized schedule-based data transmission; and (II) it differentiates the types of data transmission on the basis of data content and adopts different acknowledgment methods for different transmission types. To the best of our knowledge, no transport layer protocols have yet been designed for CRSNs. Simulation results show that the proposed protocol achieves remarkably longer network lifetime and shorter event-detection delay compared to those achieved with a conventional transport protocol, while simultaneously preserving event-detection reliability. PMID:25333288

NEUROPSYCHOLOGICAL PERFORMANCE WITHIN-PERSON VARIABILITY IS ASSOCIATED WITH REDUCED TREATMENT CONSENT CAPACITY

PubMed Central

Gurrera, Ronald J.; Karel, Michele J.; Azar, Armin R.; Moye, Jennifer

2013-01-01

OBJECTIVES The capacity of older adults to make health care decisions is often impaired in dementia and has been linked to performance on specific neuropsychological tasks. Within-person across-test neuropsychological performance variability has been shown to predict future dementia. This study examined the relationship of within-person across-test neuropsychological performance variability to a current construct of treatment decision (consent) capacity. DESIGN Participants completed a neuropsychological test battery and a standardized capacity assessment. Standard scores were used to compute mean neuropsychological performance and within-person across-test variability. SETTING Assessments were performed in the participant’s preferred location (e.g., outpatient clinic office, senior center, or home). PARTICIPANTS Participants were recruited from the community with fliers and advertisements, and consisted of men (N=79) and women (N=80) with (N=83) or without (N=76) significant cognitive impairment. MEASUREMENTS Participants completed the MacArthur Competence Assessment Tool - Treatment (MacCAT-T) and 11 neuropsychological tests commonly used in the cognitive assessment of older individuals. RESULTS Neuropsychological performance and within-person variability were independently associated with continuous and dichotomous measures of capacity, and within-person neuropsychological variability was significantly associated with within-person decisional ability variability. Prevalence of incapacity was greater than expected in participants with and without significant cognitive impairment when decisional abilities were considered separately. CONCLUSIONS These findings are consistent with an emerging construct of consent capacity in which discrete decisional abilities are differentially associated with cognitive processes, and indicate that the sensitivity and accuracy of consent capacity assessments can be improved by evaluating decisional abilities separately. PMID:23831178

Differences in Cognitive Function between Women and Men with HIV.

PubMed

Maki, Pauline M; Rubin, Leah H; Springer, Gayle; Seaberg, Eric C; Sacktor, Ned; Miller, Eric N; Valcour, Victor; Young, Mary A; Becker, James T; Martin, Eileen M

2018-05-25

Women may be more vulnerable than men to HIV-related cognitive dysfunction due to sociodemographic, lifestyle, mental health, and biological factors. However, studies to date have yielded inconsistent findings on the existence, magnitude and pattern of sex differences. We examined these issues using longitudinal data from two large, prospective, multisite, observational studies of U.S. women and men with and without HIV. Women's Interagency HIV Study (WIHS) and Multicenter AIDS Cohort Study (MACS). HIV-infected (HIV+) and uninfected (HIV-) WIHS and MACS participants completed tests of psychomotor speed, executive function, and fine motor skills. Groups were matched on HIV status, sex, age, education, and black race. Generalized linear mixed models were used to examine group differences on continuous and categorical demographically-corrected T-scores. Results were adjusted for other confounding factors. The sample (n=1420) included 710 women (429 HIV+) and 710 men (429 HIV+) (67% NonHispanic-Black; 53% high school or less). For continuous T-scores, Sex by HIV Serostatus interactions were observed on the Trail Making Test (TMT) Parts A&B, Grooved Pegboard, and Symbol Digit Modalities Test. For these tests, HIV+ women scored lower than HIV+ men, with no sex differences in HIV- individuals. In analyses of categorical scores, particularly TMT Part A and Grooved Pegboard Non-Dominant, HIV+ women also had a higher odds of impairment compared to HIV+ men. Sex differences were constant over time. Although sex differences are generally under-studied, HIV+ women versus men show cognitive disadvantages. Elucidating the mechanisms underlying these differences is critical for tailoring cognitive interventions.

Collective Leadership Measurement for the U.S. Army

DTIC Science & Technology

2014-03-01

methods employed were adapted from standard texts on survey research methods (e.g., Podsakoff, MacKenzie, Lee, & Podsakoff, 2003; Shadish, Cook...members of the research team, as well as procedures for interviews in standard research methods texts (e.g., Campion, Palmer, & Campion, 1997; Latham...critical incident protocol was based on procedures for critical incidents in standard research methods texts (e.g., Flanagan, 1954; Lowenberg, 1979

Assessing capacity to consent to treatment with cholinesterase inhibitors in dementia using a specific and standardized version of the MacArthur Competence Assessment Tool (MacCAT-T).

PubMed

Mueller, Tanja; Haberstroh, Julia; Knebel, Maren; Oswald, Frank; Kaspar, Roman; Kemper, Christoph J; Halder-Sinn, Petra; Schroeder, Johannes; Pantel, Johannes

2017-02-01

The use of assessment tools has been shown to improve the inter-rater reliability of capacity assessments. However, instrument-based capacity assessments of people with dementia face challenges. In dementia research, measuring capacity with instruments like the MacArthur Competence Assessment Tool for Treatment (MacCAT-T) mostly employ hypothetical treatment vignettes that can overwhelm the abstraction capabilities of people with dementia and are thus not always suitable for this target group. The primary aim of this study was to provide a standardized real informed consent paradigm that enables the dementia-specific properties of capacity to consent to treatment in people with dementia to be identified in a real informed consent process that is both externally valid and ethically justifiable. The sample consisted of 53 people with mild to moderate dementia and a group of 133 people without cognitive impairment. Rather than using a hypothetical treatment vignette, we used a standardized version of the MacCAT-T to assess capacity to consent to treatment with cholinesterase inhibitors in people with dementia. Inter-rater reliability, item statistics, and psychometric properties were also investigated. Intraclass correlations (ICCs) (0.951-0.990) indicated high inter-rater reliability of the standardized real informed consent paradigm. In the dementia group, performance on different items of the MacCAT-T varied. Most people with dementia were able to express a treatment choice, and were aware of the need to take a tablet. Further information on the course of the disorder and the benefits and risks of the treatment were less understood, as was comparative reasoning regarding treatment alternatives. The standardized real informed consent paradigm enabled us to detect dementia-specific characteristics of patients' capacity to consent to treatment with cholinesterase inhibitors. In order to determine suitable enhanced consent procedures for this treatment, we recommend the consideration of MacCAT-T results on an item level. People with dementia seem to understand only basic information. Our data indicate that one useful strategy to enhance capacity to consent is to reduce attention and memory demands as far as possible.

Rasch analysis of the Mini-Mental Adjustment to Cancer Scale (mini-MAC) among a heterogeneous sample of long-term cancer survivors: A cross-sectional study

PubMed Central

2012-01-01

Background The mini-Mental Adjustment to Cancer Scale (mini-MAC) is a well-recognised, popular measure of coping in psycho-oncology and assesses five cancer-specific coping strategies. It has been suggested that these five subscales could be grouped to form the over-arching adaptive and maladptive coping subscales to facilitate the interpretation and clinical application of the scale. Despite the popularity of the mini-MAC, few studies have examined its psychometric properties among long-term cancer survivors, and further validation of the mini-MAC is needed to substantiate its use with the growing population of survivors. Therefore, this study examined the psychometric properties and dimensionality of the mini-MAC in a sample of long-term cancer survivors using Rasch analysis. Methods RUMM 2030 was used to analyse the mini-MAC data (n=851). Separate Rasch analyses were conducted for each of the original mini-MAC subscales as well as the over-arching adaptive and maladaptive coping subscales to examine summary and individual model fit statistics, person separation index (PSI), response format, local dependency, targeting, item bias (or differential item functioning -DIF), and dimensionality. Results For the fighting spirit, fatalism, and helplessness-hopelessness subscales, a revised three-point response format seemed more optimal than the original four-point response. To achieve model fit, items were deleted from four of the five subscales – Anxious Preoccupation items 7, 25, and 29; Cognitive Avoidance items 11 and 17; Fighting Spirit item 18; and Helplessness-Hopelessness items 16 and 20. For those subscales with sufficient items, analyses supported unidimensionality. Combining items to form the adaptive and maladaptive subscales was partially supported. Conclusions The original five subscales required item deletion and/or rescaling to improve goodness of fit to the Rasch model. While evidence was found for overarching subscales of adaptive and maladaptive coping, extensive modifications were necessary to achieve this result. Further exploration and validation of over-arching subscales assessing adaptive and maladaptive coping is necessary with cancer survivors. PMID:22607052

Efficiently sphere-decodable physical layer transmission schemes for wireless storage networks

NASA Astrophysics Data System (ADS)

Lu, Hsiao-Feng Francis; Barreal, Amaro; Karpuk, David; Hollanti, Camilla

2016-12-01

Three transmission schemes over a new type of multiple-access channel (MAC) model with inter-source communication links are proposed and investigated in this paper. This new channel model is well motivated by, e.g., wireless distributed storage networks, where communication to repair a lost node takes place from helper nodes to a repairing node over a wireless channel. Since in many wireless networks nodes can come and go in an arbitrary manner, there must be an inherent capability of inter-node communication between every pair of nodes. Assuming that communication is possible between every pair of helper nodes, the newly proposed schemes are based on various smart time-sharing and relaying strategies. In other words, certain helper nodes will be regarded as relays, thereby converting the conventional uncooperative multiple-access channel to a multiple-access relay channel (MARC). The diversity-multiplexing gain tradeoff (DMT) of the system together with efficient sphere-decodability and low structural complexity in terms of the number of antennas required at each end is used as the main design objectives. While the optimal DMT for the new channel model is fully open, it is shown that the proposed schemes outperform the DMT of the simple time-sharing protocol and, in some cases, even the optimal uncooperative MAC DMT. While using a wireless distributed storage network as a motivating example throughout the paper, the MAC transmission techniques proposed here are completely general and as such applicable to any MAC communication with inter-source communication links.

Emotion as the Amplifier and the Primary Motive: Some Theories of Emotion with Relevance to Language Learning

ERIC Educational Resources Information Center

Oxford, Rebecca L.

2015-01-01

Emotion is crucial to living and learning. The powerful intertwining of emotion and cognition ignites learning within a complex dynamic system, which, as several sections of this paper show, also includes societal and cultural influences. As "the primary human motive" (MacIntyre, 2002a, p. 61), emotion operates as an amplifier, which…

Effectiveness of functional hand splinting and the cognitive orientation to occupational performance (CO-OP) approach in children with cerebral palsy and brain injury: two randomised controlled trial protocols

PubMed Central

2014-01-01

Background Cerebral palsy (CP) and brain injury (BI) are common conditions that have devastating effects on a child’s ability to use their hands. Hand splinting and task-specific training are two interventions that are often used to address deficits in upper limb skills, both in isolation or concurrently. The aim of this paper is to describe the method to be used to conduct two randomised controlled trials (RCT) investigating (a) the immediate effect of functional hand splints, and (b) the effect of functional hand splints used concurrently with task-specific training compared to functional hand splints alone, and to task-specific training alone in children with CP and BI. The Cognitive Orientation to Occupational Performance (CO-OP) approach will be the task-specific training approach used. Methods/Design Two concurrent trials; a two group, parallel design, RCT with a sample size of 30 participants (15 per group); and a three group, parallel design, assessor blinded, RCT with a sample size of 45 participants (15 per group). Inclusion criteria: age 4-15 years; diagnosis of CP or BI; Manual Abilities Classification System (MACS) level I – IV; hand function goals; impaired hand function; the cognitive, language and behavioural ability to participate in CO-OP. Participants will be randomly allocated to one of 3 groups; (1) functional hand splint only (n=15); (2) functional hand splint combined with task-specific training (n=15); (3) task-specific training only (n=15). Allocation concealment will be achieved using sequentially numbered, sealed opaque envelopes opened by an off-site officer after baseline measures. Treatment will be provided for a period of 2 weeks, with outcome measures taken at baseline, 1 hour after randomisation, 2 weeks and 10 weeks. The functional hand splint will be a wrist cock-up splint (+/- thumb support or supination strap). Task-specific training will involve 10 sessions of CO-OP provided in a group of 2-4 children. Primary outcome measures will be the Canadian Occupational Performance Measure (COPM) and the Goal Attainment Scale (GAS). Analysis will be conducted on an intention-to-treat basis. Discussion This paper outlines the protocol for two randomised controlled trials investigating functional hand splints and CO-OP for children with CP and BI. PMID:25023385

Supporting Beacon and Event-Driven Messages in Vehicular Platoons through Token-Based Strategies

PubMed Central

Uhlemann, Elisabeth

2018-01-01

Timely and reliable inter-vehicle communications is a critical requirement to support traffic safety applications, such as vehicle platooning. Furthermore, low-delay communications allow the platoon to react quickly to unexpected events. In this scope, having a predictable and highly effective medium access control (MAC) method is of utmost importance. However, the currently available IEEE 802.11p technology is unable to adequately address these challenges. In this paper, we propose a MAC method especially adapted to platoons, able to transmit beacons within the required time constraints, but with a higher reliability level than IEEE 802.11p, while concurrently enabling efficient dissemination of event-driven messages. The protocol circulates the token within the platoon not in a round-robin fashion, but based on beacon data age, i.e., the time that has passed since the previous collection of status information, thereby automatically offering repeated beacon transmission opportunities for increased reliability. In addition, we propose three different methods for supporting event-driven messages co-existing with beacons. Analysis and simulation results in single and multi-hop scenarios showed that, by providing non-competitive channel access and frequent retransmission opportunities, our protocol can offer beacon delivery within one beacon generation interval while fulfilling the requirements on low-delay dissemination of event-driven messages for traffic safety applications. PMID:29570676

Supporting Beacon and Event-Driven Messages in Vehicular Platoons through Token-Based Strategies.

PubMed

Balador, Ali; Uhlemann, Elisabeth; Calafate, Carlos T; Cano, Juan-Carlos

2018-03-23

Timely and reliable inter-vehicle communications is a critical requirement to support traffic safety applications, such as vehicle platooning. Furthermore, low-delay communications allow the platoon to react quickly to unexpected events. In this scope, having a predictable and highly effective medium access control (MAC) method is of utmost importance. However, the currently available IEEE 802.11p technology is unable to adequately address these challenges. In this paper, we propose a MAC method especially adapted to platoons, able to transmit beacons within the required time constraints, but with a higher reliability level than IEEE 802.11p, while concurrently enabling efficient dissemination of event-driven messages. The protocol circulates the token within the platoon not in a round-robin fashion, but based on beacon data age, i.e., the time that has passed since the previous collection of status information, thereby automatically offering repeated beacon transmission opportunities for increased reliability. In addition, we propose three different methods for supporting event-driven messages co-existing with beacons. Analysis and simulation results in single and multi-hop scenarios showed that, by providing non-competitive channel access and frequent retransmission opportunities, our protocol can offer beacon delivery within one beacon generation interval while fulfilling the requirements on low-delay dissemination of event-driven messages for traffic safety applications.

A Tuned-RF Duty-Cycled Wake-Up Receiver with -90 dBm Sensitivity.

PubMed

Bdiri, Sadok; Derbel, Faouzi; Kanoun, Olfa

2017-12-29

A novel wake-up receiver for wireless sensor networks is introduced. It operates with a modified medium access protocol (MAC), allowing low-energy consumption and practical latency. The ultra-low-power wake-up receiver operates with enhanced duty-cycled listening. The analysis of energy models of the duty-cycle-based communication is presented. All the WuRx blocks are studied to obey the duty-cycle operation. For a mean interval time for the data exchange cycle between a transmitter and a receiver over 1.7 s and a 64-bit wake-up packet detection latency of 32 ms, the average power consumption of the wake-up receiver (WuRx) reaches down to 3 μ W . It also features scalable addressing of more than 512 bit at a data rate of 128 k bit / s -1 . At a wake-up packet error rate of 10 - 2 , the detection sensitivity reaches a minimum of - 90 dBm . The combination of the MAC protocol and the WuRx eases the adoption of different kinds of wireless sensor networks. In low traffic communication, the WuRx dramatically saves more energy than that of a network that is implementing conventional duty-cycling. In this work, a prototype was realized to evaluate the intended performance.

A Tuned-RF Duty-Cycled Wake-Up Receiver with −90 dBm Sensitivity

PubMed Central

Derbel, Faouzi; Kanoun, Olfa

2017-01-01

A novel wake-up receiver for wireless sensor networks is introduced. It operates with a modified medium access protocol (MAC), allowing low-energy consumption and practical latency. The ultra-low-power wake-up receiver operates with enhanced duty-cycled listening. The analysis of energy models of the duty-cycle-based communication is presented. All the WuRx blocks are studied to obey the duty-cycle operation. For a mean interval time for the data exchange cycle between a transmitter and a receiver over 1.7 s and a 64-bit wake-up packet detection latency of 32 ms, the average power consumption of the wake-up receiver (WuRx) reaches down to 3 μW. It also features scalable addressing of more than 512 bit at a data rate of 128kbit/s−1. At a wake-up packet error rate of 10−2, the detection sensitivity reaches a minimum of −90 dBm. The combination of the MAC protocol and the WuRx eases the adoption of different kinds of wireless sensor networks. In low traffic communication, the WuRx dramatically saves more energy than that of a network that is implementing conventional duty-cycling. In this work, a prototype was realized to evaluate the intended performance. PMID:29286345

Increased dietary vitamin K intake is associated with less severe subjective memory complaint among older adults.

PubMed

Soutif-Veillon, Anne; Ferland, Guylaine; Rolland, Yves; Presse, Nancy; Boucher, Kariane; Féart, Catherine; Annweiler, Cedric

2016-11-01

Increased dietary intake of vitamin K, a fat-soluble nutrient involved in brain health and function, has been associated with better cognitive performance in older adults. Our objective was to determine whether the dietary vitamin K intake was associated with the presence and severity of subjective memory complaint among older adults. Observational, cross-sectional cohort study. One hundred sixty older adults taking no vitamin K antagonist were included. The daily dietary vitamin K intake was assessed using a 50-item food frequency questionnaire. The subjective memory complaint was assessed at the same time using the Memory Complaint Questionnaire (MAC-Q; score 0-30, best). Serious subjective memory complaint was defined as MAC-Q score ≤15. Age, gender, body mass index, education level, number of comorbidities, history of stroke, objective cognitive disorders, functional autonomy, mood, serum concentrations of vitamin B12, TSH, albumin, and estimated glomerular filtration rate were used as potential confounders. Compared to participants without serious subjective memory complaint, those with serious subjective memory complaint (n=110) had a lower mean dietary vitamin K intake (298.0±191.8μg/day versus 393.8±215.2μg/day, P=0.005). Increased log dietary vitamin K intake was positively associated with the MAC-Q score used as a quantitative variable (fully adjusted β=0.79, P=0.031), and inversely with serious subjective memory complaint (fully adjusted OR=0.34, P=0.017). Increased dietary vitamin K intake was associated with fewer and less severe subjective memory complaint in older adults taking no vitamin K antagonists. These findings provide epidemiological data supporting future vitamin K replacement trials. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

The NINDS-Canadian stroke network vascular cognitive impairment neuropsychology protocols in Chinese.

PubMed

Wong, Adrian; Xiong, Yun-yun; Wang, Defeng; Lin, Shi; Chu, Winnie W C; Kwan, Pauline W K; Nyenhuis, David; Black, Sandra E; Wong, Ka Sing Lawrence; Mok, Vincent

2013-05-01

Vascular cognitive impairment (VCI) affects up to half of stroke survivors and predicts poor outcomes. Valid and reliable assessement for VCI is lacking, especially for the Chinese population. In 2005, the National Institute of Neurological Disorders and Stroke and Canadian Stroke Network (NINDS-CSN) Harmonisation workshop proposed a set of three neuropsychology protocols for VCI evaluation. This paper is to introduce the protocol design and to report the psychometric properties of the Chinese NINDS-CSN VCI protocols. Fifty patients with mild stroke (mean National Institute of Health Stroke Scale 2.2 (SD=3.2)) and 50 controls were recruited. The NINDS-CSN VCI protocols were adapted into Chinese. We assessed protocols' (1) external validity, defined by how well the protocol summary scores differentiated patients from controls using receiver operating characteristics (ROC) curve analysis; (2) concurrent validity, by correlations with functional measures including Stroke Impact Scale memory score and Chinese Disability Assessment for Dementia; (3) internal consistency; and (4) ease of administration. All three protocols differentiated patients from controls (area under ROC for the three protocols between 0.77 to 0.79, p<0.001), and significantly correlated with the functional measures (Pearson r ranged from 0.37 to 0.51). A cut-off of 19/20 on MMSE identified only one-tenth of patients classified as impaired on the 5-min protocol. Cronbach's α across the four cognitive domains of the 60-min protocol was 0.78 for all subjects and 0.76 for stroke patients. The Chinese NINDS-CSN VCI protocols are valid and reliable for cognitive assessment in Chinese patients with mild stroke.

The Cognitive Orientation to daily Occupational Performance (CO-OP) Approach: Best responders in children with cerebral palsy and brain injury.

PubMed

Jackman, Michelle; Novak, Iona; Lannin, Natasha A; Galea, Claire; Froude, Elspeth

2018-07-01

Identifying the characteristics of individuals who are most likely to respond to a certain rehabilitation intervention is advantageous for the child, family, clinicians and the healthcare system. To investigate the individual characteristics of children with cerebral palsy or brain injury who responded best to the Cognitive Orientation to daily Occupational Performance (CO-OP) Approach. Post hoc analyses were conducted on 30 participants who participated in CO-OP within a larger randomized controlled trial. Inclusion: cerebral palsy or brain injury; age 4-15 years; Manual Abilities Classification System (MACS) I-IV; goals related to hand function; sufficient cognitive, language and behavioral ability to undertake CO-OP. Outcome measures were the Canadian Occupational Performance Measure (COPM) and Goal Attainment Scale (GAS) collected immediately following the two week intervention period. Following CO-OP, 67% (n = 20) of participants showed a statistically significant response on the COPM, and 73%(n = 22) on the GAS. Nine participants were classified as best responders. When compared to non-responders, best responders were more likely to be female (p = .025) and to have received a higher dose of CO-OP (p = .028). Neither age nor MACS were predictors of response. To be successful in CO-OP, children should meet the prerequisites of CO-OP, particularly the language and cognitive ability to set goals and communicate effectively with the therapist. In this small sample, children with comorbidities were less likely to achieve goals, females were more likely to respond and dose of therapy was important to success. Copyright © 2018 Elsevier Ltd. All rights reserved.

A Hierarchical Communication Architecture for Oceanic Surveillance Applications

PubMed Central

Macias, Elsa; Suarez, Alvaro; Chiti, Francesco; Sacco, Andrea; Fantacci, Romano

2011-01-01

The interest in monitoring applications using underwater sensor networks has been growing in recent years. The severe communication restrictions imposed by underwater channels make that efficient monitoring be a challenging task. Though a lot of research has been conducted on underwater sensor networks, there are only few concrete applications to a real-world case study. In this work, hence, we propose a general three tier architecture leveraging low cost wireless technologies for acoustic communications between underwater sensors and standard technologies, Zigbee and Wireless Fidelity (WiFi), for water surface communications. We have selected a suitable Medium Access Control (MAC) layer, after making a comparison with some common MAC protocols. Thus the performance of the overall system in terms of Signals Discarding Rate (SDR), signalling delay at the surface gateway as well as the percentage of true detection have been evaluated by simulation, pointing out good results which give evidence in applicability’s favour. PMID:22247669

Cognitive Mechanisms of Insight: The Role of Heuristics and Representational Change in Solving the Eight-Coin Problem

ERIC Educational Resources Information Center

Öllinger, Michael; Jones, Gary; Faber, Amory H.; Knoblich, Günther

2013-01-01

The 8-coin insight problem requires the problem solver to move 2 coins so that each coin touches exactly 3 others. Ormerod, MacGregor, and Chronicle (2002) explained differences in task performance across different versions of the 8-coin problem using the availability of particular moves in a 2-dimensional search space. We explored 2 further…

Concurrent and Predictive Validity of Parent Reports of Child Language at Ages 2 and 3 Years

ERIC Educational Resources Information Center

Feldman, Heidi M.; Dale, Philip S.; Campbell, Thomas F.; Colborn, D. Kathleen; Kurs-Lasky, Marcia; Rockette, Howard E.; Paradise, Jack L.

2005-01-01

The MacArthur-Bates Communicative Development Inventories (CDI; Dale, 1996; Fenson et al., 1994), parent reports about language skills, are being used increasingly in studies of theoretical and public health importance. This study (N=113) correlated scores on the CDI at ages 2 and 3 years with scores at age 3 years on tests of cognition and…

Truth, Perception, and Consequences (Proteus Monograph Series, Volume 1, Issue 1, November 2007)

DTIC Science & Technology

2007-11-01

Affective and Intellectual Autonomy in Schwartz, “Beyond individualism/ collectivism.” 56. Hofstede, Cultures and Organizations. 57. MacNulty and...strategic planning for cultural change, technology forecasting, and technology assessment. She consults at to the most senior levels within the...Department of Defense. Her current DoD projects bring together her knowledge of strategy, cultures , and cognition to help in understanding our

A Scalable and Dynamic Testbed for Conducting Penetration-Test Training in a Laboratory Environment

DTIC Science & Technology

2015-03-01

entry point through which to execute a payload to accomplish a higher-level goal: executing arbitrary code, escalating privileges , pivoting...Mobile Ad Hoc Network Emulator (EMANE)26 can emulate the entire network stack (physical to application -layer protocols). 2. Methodology To build a...to host Windows, Linux, MacOS, Android , and other operating systems without much effort. 4 E. A simple and automatic “restore” function: Many

United States Special Operations Command (USSOCOM): Construction Management Handbook

DTIC Science & Technology

2010-02-11

installation B-Hut Road Work Sea-Hut Water Well and Pump House Brick and Mortar billets D. Oversight Program Oversight of contracts is critical to the...often asked to fulfill construction requirements in austere locations with little or no training in construction terminology, concepts, and protocols...contracting arm of SOAL is the Director of Procurement (also known as SOAL-K), located within the USSOCOM Headquarters on MacDill AFB, Florida. SOAL-K

Protocol Analysis of Group Problem Solving in Mathematics: A Cognitive-Metacognitive Framework for Assessment.

ERIC Educational Resources Information Center

Artzt, Alice F.; Armour-Thomas, Eleanor

The roles of cognition and metacognition were examined in the mathematical problem-solving behaviors of students as they worked in small groups. As an outcome, a framework that links the literature of cognitive science and mathematical problem solving was developed for protocol analysis of mathematical problem solving. Within this framework, each…

Sensitivity and Specificity of a Five-Minute Cognitive Screening Test in Patients With Heart Failure.

PubMed

Cameron, Janette D; Gallagher, Robyn; Pressler, Susan J; McLennan, Skye N; Ski, Chantal F; Tofler, Geoffrey; Thompson, David R

2016-02-01

Cognitive impairment occurs in up to 80% of patients with heart failure (HF). The National Institute for Neurological Disorders and Stroke (NINDS) and the Canadian Stroke Network (CSN) recommend a 5-minute cognitive screening protocol that has yet to be psychometrically evaluated in HF populations. The aim of this study was to conduct a secondary analysis of the sensitivity and specificity of the NINDS-CSN brief cognitive screening protocol in HF patients. The Montreal Cognitive Assessment (MoCA) was administered to 221 HF patients. The NINDS-CSN screen comprises 3 MoCA items, with lower scores indicating poorer cognitive function. Receiver operator characteristic (ROC) curves were constructed, determining the sensitivity, specificity and appropriate cutoff scores of the NINDS-CSN screen. In an HF population aged 76 ± 12 years, 136 (62%) were characterized with cognitive impairment (MoCA <26). Scores on the NINDS-CSN screen ranged from 3-11. The area under the receiver operating characteristic curve indicated good accuracy in screening for cognitive impairment (0.88; P < .01; 95% CI 0.83-0.92). A cutoff score of ≤9 provided 89% sensitivity and 71% specificity. The NINDS-CSN protocol offers clinicians a feasible telephone method to screen for cognitive impairment in patients with HF. Future studies should include a neuropsychologic battery to more comprehensively examine the diagnostic accuracy of brief cognitive screening protocols. Copyright © 2016 Elsevier Inc. All rights reserved.

Light absorption enhancement of black carbon from urban haze in Northern China winter.

PubMed

Chen, Bing; Bai, Zhe; Cui, Xinjuan; Chen, Jianmin; Andersson, August; Gustafsson, Örjan

2017-02-01

Atmospheric black carbon (BC) is an important pollutant for both air quality and Earth's energy balance. Estimates of BC climate forcing remain highly uncertain, e.g., due to the mixing with non-absorbing components. Non-absorbing aerosols create a coating on BC and may thereby act as a lens which may enhance the light absorption. However, this absorption enhancement is poorly constrained. To this end a two-step solvent dissolution protocol was employed to remove both organic and inorganic coatings, and then investigate their effects on BC light absorption. Samples were collected at a severely polluted urban area, Jinan, in the North China Plain (NCP) during February 2014. The BC mass absorption cross-section (MAC) was measured for the aerosol samples before and after the solvent-decoating treatment, and the enhancement of MAC (E MAC ) from the coating effect was defined as the ratio. A distinct diurnal pattern for the enhancement was observed, with E MAC 1.3 ± 0.3 (1 S.D.) in the morning, increasing to 2.2 ± 1.0 in the afternoon, after that dropping to 1.5 ± 0.8 in the evening-night. The BC absorption enhancement primarily was associated with urban-scale photochemical production of nitrate and sulfate aerosols. In addition to that, regional-scale haze plume with increasing sulfate levels strengthened the absorption enhancement. These observations offer direct evidence for an increased absorption enhancement of BC due to severe air pollution in China. Copyright © 2016 Elsevier Ltd. All rights reserved.

COGNITIVE-HD study: protocol of an observational study of neurocognitive functioning and association with clinical outcomes in adults with end-stage kidney disease treated with haemodialysis.

PubMed

Palmer, Suetonia C; Ruospo, Marinella; Barulli, Maria Rosaria; Iurillo, Annalisa; Saglimbene, Valeria; Natale, Patrizia; Gargano, Letizia; Murgo, Angelo M; Loy, Clement; van Zwieten, Anita; Wong, Germaine; Tortelli, Rosanna; Craig, Jonathan C; Johnson, David W; Tonelli, Marcello; Hegbrant, Jörgen; Wollheim, Charlotta; Logroscino, Giancarlo; Strippoli, G F M

2015-12-09

The prevalence of cognitive impairment may be increased in adults with end-stage kidney disease compared with the general population. However, the specific patterns of cognitive impairment and association of cognitive dysfunction with activities of daily living and clinical outcomes (including withdrawal from treatment) among haemodialysis patients remain incompletely understood. The COGNITIVE impairment in adults with end-stage kidney disease treated with HemoDialysis (COGNITIVE-HD) study aims to characterise the age-adjusted and education-adjusted patterns of cognitive impairment (using comprehensive testing for executive function, perceptual-motor function, language, learning and memory, and complex attention) in patients on haemodialysis and association with clinical outcomes. A prospective, longitudinal, cohort study of 750 adults with end-stage kidney disease treated with long-term haemodialysis has been recruited within haemodialysis centres in Italy (July 2013 to April 2014). Testing for neurocognitive function was carried out by a trained psychologist at baseline to assess cognitive functioning. The primary study factor is cognitive impairment and secondary study factors will be specific domains of cognitive function. The primary outcome will be total mortality. Secondary outcomes will be cause-specific mortality, major cardiovascular events, fatal and non-fatal myocardial infarction and stroke, institutionalisation, and withdrawal from treatment at 12 months. This protocol was approved before study conduct by the following responsible ethics committees: Catania (approval reference 186/BE; 26/09/2013), Agrigento (protocol numbers 61-62; 28/6/2013), USL Roma C (CE 39217; 24/6/2013), USL Roma F (protocol number 0041708; 23/7/2013), USL Latina (protocol number 20090/A001/2011; 12/7/2013), Trapani (protocol number 3413; 16/7/2013) and Brindisi (protocol number 40259; 6/6/2013). All participants have provided written and informed consent and can withdraw from the study at any time. The findings of the study will be disseminated through peer-reviewed journals and national and international conference presentations and to the participants through communication within the dialysis network in which this study is conducted. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Magnetic cell sorting purification of differentiated embryonic stem cells stably expressing truncated human CD4 as surface marker.

PubMed

David, Robert; Groebner, Michael; Franz, Wolfgang-Michael

2005-04-01

Embryonic stem (ES) cells offer great potential in regenerative medicine and tissue engineering. Clinical applications are still hampered by the lack of protocols for gentle, high-yield isolation of specific cell types for transplantation expressing no immunogenic markers. We describe labeling of stably transfected ES cells expressing a human CD4 molecule lacking its intracellular domain (DeltaCD4) under control of the phosphoglycerate kinase promoter for magnetic cell sorting (MACS). To track the labeled ES cells, we fused DeltaCD4 to an intracellular enhanced green fluorescent protein domain (DeltaCD4EGFP). We showed functionality of the membrane-bound fluorescent fusion protein and its suitability for MACS leading to purities greater than 97%. Likewise, expression of DeltaCD4 yielded up to 98.5% positive cells independently of their differentiation state. Purities were not limited by the initial percentage of DeltaCD4(+) cells, ranging from 0.6%-16%. The viability of MACS-selected cells was demonstrated by reaggregation and de novo formation of embryoid bodies developing all three germ layers. Thus, expression of DeltaCD4 in differentiated ES cells may enable rapid, high-yield purification of a desired cell type for tissue engineering and transplantation studies.

RNA-transfection of γ/δ T cells with a chimeric antigen receptor or an α/β T-cell receptor: a safer alternative to genetically engineered α/β T cells for the immunotherapy of melanoma.

PubMed

Harrer, Dennis C; Simon, Bianca; Fujii, Shin-Ichiro; Shimizu, Kanako; Uslu, Ugur; Schuler, Gerold; Gerer, Kerstin F; Hoyer, Stefanie; Dörrie, Jan; Schaft, Niels

2017-08-17

Adoptive T-cell therapy relying on conventional T cells transduced with T-cell receptors (TCRs) or chimeric antigen receptors (CARs) has caused substantial tumor regression in several clinical trials. However, genetically engineered T cells have been associated with serious side-effects due to off-target toxicities and massive cytokine release. To obviate these concerns, we established a protocol adaptable to GMP to expand and transiently transfect γ/δ T cells with mRNA. PBMC from healthy donors were stimulated using zoledronic-acid or OKT3 to expand γ/δ T cells and bulk T cells, respectively. Additionally, CD8 + T cells and γ/δ T cells were MACS-isolated from PBMC and expanded with OKT3. Next, these four populations were electroporated with RNA encoding a gp100/HLA-A2-specific TCR or a CAR specific for MCSP. Thereafter, receptor expression, antigen-specific cytokine secretion, specific cytotoxicity, and killing of the endogenous γ/δ T cell-target Daudi were analyzed. Using zoledronic-acid in average 6 million of γ/δ T cells with a purity of 85% were generated from one million PBMC. MACS-isolation and OKT3-mediated expansion of γ/δ T cells yielded approximately ten times less cells. OKT3-expanded and CD8 + MACS-isolated conventional T cells behaved correspondingly similar. All employed T cells were efficiently transfected with the TCR or the CAR. Upon respective stimulation, γ/δ T cells produced IFNγ and TNF, but little IL-2 and the zoledronic-acid expanded T cells exceeded MACS-γ/δ T cells in antigen-specific cytokine secretion. While the cytokine production of γ/δ T cells was in general lower than that of conventional T cells, specific cytotoxicity against melanoma cell lines was similar. In contrast to OKT3-expanded and MACS-CD8 + T cells, mock-electroporated γ/δ T cells also lysed tumor cells reflecting the γ/δ T cell-intrinsic anti-tumor activity. After transfection, γ/δ T cells were still able to kill MHC-deficient Daudi cells. We present a protocol adaptable to GMP for the expansion of γ/δ T cells and their subsequent RNA-transfection with tumor-specific TCRs or CARs. Given the transient receptor expression, the reduced cytokine release, and the equivalent cytotoxicity, these γ/δ T cells may represent a safer complementation to genetically engineered conventional T cells in the immunotherapy of melanoma (Exper Dermatol 26: 157, 2017, J Investig Dermatol 136: A173, 2016).

Comparison of two MAC protocols based on LEO satellite networks

NASA Astrophysics Data System (ADS)

Guan, Mingxiang; Wang, Ruichun

2009-12-01

With the development of LEO satellite communication, it is the basic requirement that various kinds of services will be provided. Considering that weak channel collision detection ability, long propagation delay and heavy load in LEO satellite communication system, a valid adaptive access control protocol APRMA is proposed. Different access probability functions for different services are obtained and appropriate access probabilities for voice and data users are updated slot by slot based on the estimation of the voice traffic and the channel status. Finally simulation results demonstrate that the performance of system is improved by the APRMA compared with the conventional PRMA, with an acceptable trade-off between QoS of voice and delay of data. Also the APRMA protocol will be suitable for HAPS (high altitude platform station) with the characters of weak channel collision detection ability, long propagation delay and heavy load.

Pre-cut Filter Paper for Detecting Anti-Japanese Encephalitis Virus IgM from Dried Cerebrospinal Fluid Spots

PubMed Central

Bharucha, Tehmina; Chanthongthip, Anisone; Phuangpanom, Soumphou; Phonemixay, Ooyanong; Sengvilaipaseuth, Onanong; Vongsouvath, Manivanh; Lee, Sue; Newton, Paul N.; Dubot-Pérès, Audrey

2016-01-01

Background The use of filter paper as a simple, inexpensive tool for storage and transportation of blood, ‘Dried Blood Spots’ or Guthrie cards, for diagnostic assays is well-established. In contrast, there are a paucity of diagnostic evaluations of dried cerebrospinal fluid (CSF) spots. These have potential applications in low-resource settings, such as Laos, where laboratory facilities for central nervous system (CNS) diagnostics are only available in Vientiane. In Laos, a major cause of CNS infection is Japanese encephalitis virus (JEV). We aimed to develop a dried CSF spot protocol and to evaluate its diagnostic performance using the World Health Organisation recommended anti-JEV IgM antibody capture enzyme-linked immunosorbent assay (JEV MAC-ELISA). Methodology and Principal Findings Sample volumes, spotting techniques and filter paper type were evaluated using a CSF-substitute of anti-JEV IgM positive serum diluted in Phosphate Buffer Solution (PBS) to end-limits of detection by JEV MAC-ELISA. A conventional protocol, involving eluting one paper punch in 200μl PBS, did not detect the end-dilution, nor did multiple punches utilising diverse spotting techniques. However, pre-cut filter paper enabled saturation with five times the volume of CSF-substitute, sufficiently improving sensitivity to detect the end-dilution. The diagnostic accuracy of this optimised protocol was compared with routine, neat CSF in a pilot, retrospective study of JEV MAC-ELISA on consecutive CSF samples, collected 2009–15, from three Lao hospitals. In comparison to neat CSF, 132 CSF samples stored as dried CSF spots for one month at 25–30°C showed 81.6% (65.7–92.3 95%CI) positive agreement, 96.8% (91.0–99.3 95%CI) negative agreement, with a kappa coefficient of 0.81 (0.70–0.92 95%CI). Conclusions/Significance The novel design of pre-cut filter paper saturated with CSF could provide a useful tool for JEV diagnostics in settings with limited laboratory access. It has the potential to improve national JEV surveillance and inform vaccination policies. The saturation of filter paper has potential use in the wider context of pathogen detection, including dried spots for detecting other analytes in CSF, and other body fluids. PMID:26986061

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

Meyer, Jeremy, E-mail: jeremy.meyer@hcuge.ch; Unit of Surgical Research, University of Geneva, Rue Michel-Servet 1, 1206 Genève; Lacotte, Stéphanie, E-mail: stephanie.lacotte@unige.ch

The objective of the present study was to develop an accurate and reproducible method for liver sinusoidal endothelial cell (LSEC) isolation in mice. Non-parenchymal cells were isolated using a modified two-step collagenase digestion combined with Optiprep density gradient centrifugation. LSEC were further purified using two prevalent methods, short-term selective adherence and CD146+ magnetic-activated cell sorting (MACS), and compared in terms of cell yield, viability and purity to our purification technique using CD11b cell depletion combined with long-term selective adherence. LSEC purification using our technique allowed to obtain 7.07±3.80 million LSEC per liver, while CD146+ MACS and short-term selective adherence yieldedmore » 2.94±1.28 and 0.99±0.66 million LSEC, respectively. Purity of the final cell preparation reached 95.10±2.58% when using our method. In contrast, CD146+ MACS and short-term selective adherence gave purities of 86.75±3.26% and 47.95±9.82%, respectively. Similarly, contamination by non-LSEC was the lowest when purification was performed using our technique, with a proportion of contaminating macrophages of only 1.87±0.77%. Further, isolated cells analysed by scanning electron microscopy presented typical LSEC fenestrations organized in sieve plates, demonstrating that the technique allowed to isolate bona fide LSEC. In conclusion, we described a reliable and reproducible technique for the isolation of high yields of pure LSEC in mice. This protocol provides an efficient method to prepare LSEC for studying their biological functions. - Highlights: • This protocol provides an efficient method to prepare primary mouse LSEC for studying their biological functions. • The liver cell dispersion step was improved by performing a retrograde cannulation of the liver. • The cell yield and the purity obtained were higher than comparative techniques in mice. • Contaminating macrophages were removed by introducing a CD11b- magnetic –activated cell sorting step.« less

A testbed for the evaluation of computer aids for enroute flight path planning

NASA Technical Reports Server (NTRS)

Smith, Philip J.; Layton, Chuck; Galdes, Deb; Mccoy, C. E.

1990-01-01

A simulator study of the five airline flight crews engaged in various enroute planning activities has been conducted. Based on a cognitive task analysis of this data, a flight planning workstation has been developed on a Mac II controlling three color monitors. This workstation is being used to study design concepts to support the flight planning activities of dispatchers and flight crews in part-task simulators.

Assessing future expectations and the two-dimensional model of affect in an Italian population.

PubMed

Corno, Giulia; Molinari, Guadalupe; Baños, Rosa Maria

2017-03-01

Future-directed thinking has been described as part of two underlying systems that integrate dimensions of affect, motivational systems, orientation to the future, and future expectations, which are initiated at the cognitive, affective, biological, behavioral, and motivational levels. The main aim of the present study is to test the two underlying frameworks model and explore future expectations in a general Italian-speaking population (N=345). Therefore, the second aim of the present paper is to confirm the factorial structure of the Subjective Probability Task (SPT; MacLeod et al., 1996), a questionnaire designed to assess specific positive and negative orientations towards the future. Results showed that the SPT has good psychometric properties and it is a reliable instrument to assess future-directed thinking. Moreover, our findings confirmed the role of future expectancies as cognitive correlates of depression and anxiety. Differently from previous studies (Clark and Watson, 1991; MacLeod et al., 1996), our results did not confirm that depression was characterized by low positive affect. We believe this paper contributes to the understanding of future expectancies and their relation with anxiety and depression, and will help to expand the availability of an instrument to assess future directed thinking. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

Coping with Pain in the Motivational Context of Values: Comparison between an Acceptance-Based and a Cognitive Control-Based Protocol

ERIC Educational Resources Information Center

Paez-Blarrina, Marisa; Luciano, Carmen; Gutierrez-Martinez, Olga; Valdivia, Sonsoles; Rodriguez-Valverde, Miguel; Ortega, Jose

2008-01-01

This study compares the effect of an acceptance-based protocol (ACT) and a cognitive control-based (CONT) protocol on three measures of pain coping: tolerance, self-report, and believability. Specific methodological controls were employed to further isolate the role of the value of participating in a pain task, compared to previous investigations…

A shortened protocol for assessing cognitive bias in rats.

PubMed

Brydges, Nichola M; Hall, Lynsey

2017-07-15

Reliable measurement of affective state in animals is a significant goal of animal welfare. Such measurements would also improve the validity of pre-clinical mental health research which relies on animal models. However, at present, affective states in animals are inaccessible to direct measurement. In humans, changes in cognitive processing can give reliable indications of emotional state. Therefore, similar techniques are increasingly being used to gain proxy measures of affective states in animals. In particular, the 'cognitive bias' assay has gained popularity in recent years. Major disadvantages of this technique include length of time taken for animals to acquire the task (typically several weeks), negative experiences associated with task training, and issues of motivation. Here we present a shortened cognitive bias protocol using only positive reinforcers which must actively be responded to. The protocol took an average of 4days to complete, and produced similar results to previous, longer methods (minimum 30days). Specifically, rats housed in standard laboratory conditions demonstrated negative cognitive biases when presented with ambiguous stimuli, and took longer to make a decision when faced with an ambiguous stimulus. Compared to previous methods, this protocol is significantly shorter (average 4days vs. minimum 30days), utilises only positive reinforcers to avoid inducing negative affective states, and requires active responses to all cues, avoiding potential confounds of motivational state. We have successfully developed a shortened cognitive bias protocol, suitable for use with laboratory rats. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.

Development and validation of an ELISA kit (YF MAC-HD) to detect IgM to yellow fever virus.

PubMed

Basile, Alison Jane; Goodman, Christin; Horiuchi, Kalanthe; Laven, Janeen; Panella, Amanda J; Kosoy, Olga; Lanciotti, Robert S; Johnson, Barbara W

2015-12-01

Yellow fever virus (YFV) is endemic in tropical and sub-tropical regions of the world, with around 180,000 human infections a year occurring in Africa. Serologic testing is the chief laboratory diagnostic means of identifying an outbreak and to inform the decision to commence a vaccination campaign. The World Health Organization disseminates the reagents for YFV testing to African reference laboratories, and the US Centers for Disease Control and Prevention (CDC) is charged with producing and providing these reagents. The CDC M-antibody capture ELISA is a 2-day test, requiring titration of reagents when new lots are received, which leads to inconsistency in testing and wastage of material. Here we describe the development of a kit-based assay (YF MAC-HD) based upon the CDC method, that is completed in approximately 3.5h, with equivocal samples being reflexed to an overnight protocol. The kit exhibits >90% accuracy when compared to the 2-day test. The kits were designed for use with a minimum of equipment and are stored at 4°C, removing the need for freezing capacity. This kit is capable of tolerating temporary sub-optimal storage conditions which will ease shipping or power outage concerns, and a shelf life of >6 months was demonstrated with no deterioration in accuracy. All reagents necessary to run the YF MAC-HD are included in the kit and are single-use, with 8 or 24 sample options per kit. Field trials are envisioned for the near future, which will enable refinement of the method. The use of the YF MAC-HD is anticipated to reduce materials wastage, and improve the quality and consistency of YFV serologic testing in endemic areas. Published by Elsevier B.V.

The periplasmic membrane proximal domain of MacA acts as a switch in stimulation of ATP hydrolysis by MacB transporter.

PubMed

Modali, Sita D; Zgurskaya, Helen I

2011-08-01

Escherichia coli MacAB-TolC is a tripartite macrolide efflux transporter driven by hydrolysis of ATP. In this complex, MacA is the periplasmic membrane fusion protein that stimulates the activity of MacB transporter and establishes the link with the outer membrane channel TolC. The molecular mechanism by which MacA stimulates MacB remains unknown. Here, we report that the periplasmic membrane proximal domain of MacA plays a critical role in functional MacA-MacB interactions and stimulation of MacB ATPase activity. Binding of MacA to MacB stabilizes the ATP-bound conformation of MacB, whereas interactions with both MacB and TolC affect the conformation of MacA. A single G353A substitution in the C-terminus of MacA inactivates MacAB-TolC function by changing the conformation of the membrane proximal domain of MacA and disrupting the proper assembly of the MacA-MacB complex. We propose that MacA acts in transport by promoting MacB transition into the closed ATP-bound conformation and in this respect, is similar to the periplasmic solute-binding proteins. © 2011 Blackwell Publishing Ltd.

The periplasmic membrane proximal domain of MacA acts as a switch in stimulation of ATP hydrolysis by MacB transporter

PubMed Central

Modali, Sita D.; Zgurskaya, Helen I.

2011-01-01

Escherichia coli MacAB-TolC is a tri-partite macrolide efflux transporter driven by hydrolysis of ATP. In this complex, MacA is the periplasmic membrane fusion protein that stimulates the activity of MacB transporter and establishes the link with the outer membrane channel TolC. The molecular mechanism by which MacA stimulates MacB remains unknown. Here, we report that the periplasmic membrane proximal domain of MacA plays a critical role in functional MacA-MacB interactions and stimulation of MacB ATPase activity. Binding of MacA to MacB stabilizes the ATP-bound conformation of MacB, whereas interactions with both MacB and TolC affect the conformation of MacA. A single G353A substitution in the C-terminus of MacA inactivates MacAB-TolC function by changing the conformation of the membrane proximal domain of MacA and disrupting the proper assembly of the MacA-MacB complex. We propose that MacA acts in transport by promoting MacB transition into the closed ATP-bound conformation and in this respect, is similar to the periplasmic solute-binding proteins. PMID:21696464

Cognitive Hypnotherapy as a Transdiagnostic Protocol for Emotional Disorders.

PubMed

Alladin, Assen; Amundson, Jon

2016-01-01

This article describes cognitive hypnotherapy (CH), an integrative treatment that provides an evidence-based framework for synthesizing clinical practice and research. CH combines hypnotherapy with cognitive-behavior therapy in the management of emotional disorders. This blended version of clinical practice meets criteria for an assimilative model of integrative psychotherapy, which incorporates both theory and empirical findings. Issues related to (a) additive effect of hypnosis in treatment, (b) transdiagnostic consideration, and (c) unified treatment protocols in the treatment of emotional disorders are considered in light of cognitive hypnotherapy.

An Energy-Efficient Sleep Mode in IEEE 802.15.4 by Considering Sensor Device Mobility

NASA Astrophysics Data System (ADS)

Kim, Jinho; Lee, Jun; Hong, Choong Seon; Lee, Sungwon

The current version of IEEE 802.15.4 MAC protocol does not support energy-efficient mobility for the low-power device. In this paper, we propose an energy-efficient sleep mode as part of the IEEE 802.15.4 that can conserve energy by considering mobility of mobile sensor devices. The proposed energy-efficient sleep mode dynamically extends the sleep interval if there is no data to transmit from the device or receive from corresponding nodes.

Joint Cross-Layer Design for Wireless QoS Content Delivery

NASA Astrophysics Data System (ADS)

Chen, Jie; Lv, Tiejun; Zheng, Haitao

2005-12-01

In this paper, we propose a joint cross-layer design for wireless quality-of-service (QoS) content delivery. Central to our proposed cross-layer design is the concept of adaptation. Adaptation represents the ability to adjust protocol stacks and applications to respond to channel variations. We focus our cross-layer design especially on the application, media access control (MAC), and physical layers. The network is designed based on our proposed fast frequency-hopping orthogonal frequency division multiplex (OFDM) technique. We also propose a QoS-awareness scheduler and a power adaptation transmission scheme operating at both the base station and mobile sides. The proposed MAC scheduler coordinates the transmissions of an IP base station and mobile nodes. The scheduler also selects appropriate transmission formats and packet priorities for individual users based on current channel conditions and the users' QoS requirements. The test results show that our cross-layer design provides an excellent framework for wireless QoS content delivery.

Analytical Model of Large Data Transactions in CoAP Networks

PubMed Central

Ludovici, Alessandro; Di Marco, Piergiuseppe; Calveras, Anna; Johansson, Karl H.

2014-01-01

We propose a novel analytical model to study fragmentation methods in wireless sensor networks adopting the Constrained Application Protocol (CoAP) and the IEEE 802.15.4 standard for medium access control (MAC). The blockwise transfer technique proposed in CoAP and the 6LoWPAN fragmentation are included in the analysis. The two techniques are compared in terms of reliability and delay, depending on the traffic, the number of nodes and the parameters of the IEEE 802.15.4 MAC. The results are validated trough Monte Carlo simulations. To the best of our knowledge this is the first study that evaluates and compares analytically the performance of CoAP blockwise transfer and 6LoWPAN fragmentation. A major contribution is the possibility to understand the behavior of both techniques with different network conditions. Our results show that 6LoWPAN fragmentation is preferable for delay-constrained applications. For highly congested networks, the blockwise transfer slightly outperforms 6LoWPAN fragmentation in terms of reliability. PMID:25153143

Design and Analysis of Underwater Acoustic Networks with Reflected Links

NASA Astrophysics Data System (ADS)

Emokpae, Lloyd

Underwater acoustic networks (UWANs) have applications in environmental state monitoring, oceanic profile measurements, leak detection in oil fields, distributed surveillance, and navigation. For these applications, sets of nodes are employed to collaboratively monitor an area of interest and track certain events or phenomena. In addition, it is common to find autonomous underwater vehicles (AUVs) acting as mobile sensor nodes that perform search-and-rescue missions, reconnaissance in combat zones, and coastal patrol. These AUVs are to work cooperatively to achieve a desired goal and thus need to be able to, in an ad-hoc manner, establish and sustain communication links in order to ensure some desired level of quality of service. Therefore, each node is required to adapt to environmental changes and be able to overcome broken communication links caused by external noise affecting the communication channel due to node mobility. In addition, since radio waves are quickly absorbed in the water medium, it is common for most underwater applications to rely on acoustic (or sound) rather than radio channels for mid-to-long range communications. However, acoustic channels pose multiple challenging issues, most notably the high transmission delay due to slow signal propagation and the limited channel bandwidth due to high frequency attenuation. Moreover, the inhomogeneous property of the water medium affects the sound speed profile while the signal surface and bottom reflections leads to multipath effects. In this dissertation, we address these networking challenges by developing protocols that take into consideration the underwater physical layer dynamics. We begin by introducing a novel surface-based reflection scheme (SBR), which takes advantage of the multipath effects of the acoustic channel. SBR works by using reflections from the water surface, and bottom, to establish non-line-of-sight (NLOS) communication links. SBR makes it possible to incorporate both line-of-sight (LOS) and NLOS links by utilizing directional antennas, which will boost the signal-to-noise ratio (SNR) at the receiver while promoting NLOS usage. In our model, we employ a directional underwater acoustic antenna composed of an array of hydrophones that can be summed up at various phases and amplitudes resulting in a beam-former. We have also adopted a practical multimodal directional transducer concept which generates both directional and omni-directional beam patterns by combining the fundamental vibration modes of a cylindrical acoustic radiator. This allows the transducer to be electrically controlled and steered by simply adjusting the electrical voltage weights. A prototype acoustic modem is then developed to utilize the multimodal directional transducer for both LOS and NLOS communication. The acoustic modem has also been used as a platform for empirically validating our SBR communication model in a tank and with empirical data. Networking protocols have been developed to exploit the SBR communication model. These protocols include node discovery and localization, directional medium access control (D-MAC) and geographical routing. In node discovery and localization, each node will utilize SBR-based range measurements to its neighbors to determine their relative position. The D-MAC protocol utilizes directional antennas to increase the network throughput due to the spatial efficiency of the antenna model. In the proposed reflection-enabled directional MAC protocol (RED-MAC), each source node will be able to determine if an obstacle is blocking the LOS link to the destination and switch to the best NLOS link by utilizing surface/bottom reflections. Finally, we have developed a geographical routing algorithm which aims to establish the best stable route from a source node to a destination node. The optimized route is selected to achieve maximum network throughput. Extensive analysis of the network throughput when utilizing directional antennas is also presented to show the benefits of directional communication on the overall network throughput.

A Brief Survey of Media Access Control, Data Link Layer, and Protocol Technologies for Lunar Surface Communications

NASA Technical Reports Server (NTRS)

Wallett, Thomas M.

2009-01-01

This paper surveys and describes some of the existing media access control and data link layer technologies for possible application in lunar surface communications and the advanced wideband Direct Sequence Code Division Multiple Access (DSCDMA) conceptual systems utilizing phased-array technology that will evolve in the next decade. Time Domain Multiple Access (TDMA) and Code Division Multiple Access (CDMA) are standard Media Access Control (MAC) techniques that can be incorporated into lunar surface communications architectures. Another novel hybrid technique that is recently being developed for use with smart antenna technology combines the advantages of CDMA with those of TDMA. The relatively new and sundry wireless LAN data link layer protocols that are continually under development offer distinct advantages for lunar surface applications over the legacy protocols which are not wireless. Also several communication transport and routing protocols can be chosen with characteristics commensurate with smart antenna systems to provide spacecraft communications for links exhibiting high capacity on the surface of the Moon. The proper choices depend on the specific communication requirements.

Effects of an Exercise Protocol for Improving Handgrip Strength and Walking Speed on Cognitive Function in Patients with Chronic Stroke.

PubMed

Kim, Jaeeun; Yim, Jongeun

2017-11-13

BACKGROUND Handgrip strength and walking speed predict and influence cognitive function. We aimed to investigate an exercise protocol for improving handgrip strength and walking speed, applied to patients with chronic stroke who had cognitive function disorder. MATERIAL AND METHODS Twenty-nine patients with cognitive function disorder participated in this study, and were randomly divided into one of two groups: exercise group (n=14) and control group (n=15). Both groups underwent conventional physical therapy for 60 minutes per day. Additionally, the exercise group followed an exercise protocol for handgrip using the hand exerciser, power web exerciser, Digi-Flex (15 minutes); and treadmill-based weight loading training on their less-affected leg (15 minutes) using a sandbag for 30 minutes, three times per day, for six weeks. Outcomes, including cognitive function and gait ability, were measured before and after the training. RESULTS The Korean version of Montreal Cognitive Assessment (K-MoCA), Stroop test (both simple and interference), Trail Making-B, Timed Up and Go, and 10-Meter Walk tests (p<0.05) yielded improved results for the exercise group compared with the control group. Importantly, the K-MoCA, Timed Up and Go, and 10-Meter Walk test results were significantly different between the two groups (p<0.05). CONCLUSIONS The exercise protocol for improving handgrip strength and walking speed had positive effects on cognitive function in patients with chronic stroke.

Effect of beta and gamma neurofeedback on memory and intelligence in the elderly.

PubMed

Staufenbiel, S M; Brouwer, A-M; Keizer, A W; van Wouwe, N C

2014-01-01

Recent research showed a correlation between cognitive decline and a decrease of EEG gamma activity. In the present double-blind randomized control study, we investigated whether gamma and beta neurofeedback protocols, that have been shown to modulate performance on cognitive control and memory in young adults, also leads to increased brain activity and cognitive performance in elderly. Twenty older adults either performed eight 30-min gamma neurofeedback session or beta neurofeedback session within a period of 21 days. Cognitive performance was determined before and after the training through an IQ and memory task and we added a subjective well-being questionnaire. Both neurofeedback training protocols resulted in a significant increase of the brain activity within each training session, suggesting that the aging brain is still trainable. However, we found no effects on cognitive performance or transfer of the feedback beyond the trainings. We discuss several possible reasons for the lack of training on rest measurements and cognition and ways to improve the feedback protocols for future studies. Copyright © 2013 Elsevier B.V. All rights reserved.

The relationship between cognitive and neuroimaging outcomes in children treated for acute lymphoblastic leukemia with chemotherapy only: A systematic review.

PubMed

Hearps, Simone; Seal, Marc; Anderson, Vicki; McCarthy, Maria; Connellan, Madeleine; Downie, Peter; De Luca, Cinzia

2017-02-01

Cognitive late-effects have been identified in patients treated with chemotherapy-only protocols for childhood acute lymphoblastic leukemia (ALL), yet the underlying neuropathology is not well understood. This review synthesized recent findings from eight articles investigating the relationship between neurocognitive and neuroimaging outcomes for patients treated for ALL with chemotherapy-only protocols. Reported cognitive domains, imaging methods, and neuroanatomy examined were variable. Despite this, 62.5% (n = 5) of the reviewed studies found a significant relationship between cognitive and imaging outcomes. Greater understanding of the effects of treatment on neuroanatomy and cognitive outcomes is critical for proactively managing ALL cognitive late-effects. Research directions are suggested. © 2016 Wiley Periodicals, Inc.

Support For International Conference on Physiological and Cognitive Performance In Extreme Environments

DTIC Science & Technology

2000-07-01

W.S. Roberts and M.A Febbraio 8 INVITED LECTURE 2: HEAT STRESS AND EXERCISE METABOLISM M.A Febbraio 12 PAPER 3: EFFECT OF ENVIRONMENTAL...R. Snow 72 PAPER 14: WHOLE-BODY PRE-COOLING: THERMAL, CARDIOVASCULAR AND METABOLIC CONSEQUENCES. A.D. MacDonald, J. Booth, A.L. Fogarty, K.A...French 191 POSTER 8: ORIGIN AND REGULATION OF METABOLIC HEAT KP. Ivanov 195 POSTER 9: RESTORATION OF PHYSIOLOGICAL FUNCTIONS IN A COOLED

Subjective Cognitive Complaints and Objective Cognitive Function in Aging: A Systematic Review and Meta-Analysis of Recent Cross-Sectional Findings.

PubMed

Burmester, Bridget; Leathem, Janet; Merrick, Paul

2016-12-01

Research investigating how subjective cognitive complaints (SCCs) might reliably indicate impairments in objective cognitive functioning has produced highly varied findings, and despite attempts to synthesise this literature (e.g., Jonker et al. International Journal of Geriatric Psychiatry, 15, 983-991, 2000; Reid and MacLullich Dementia and Geriatric Cognitive Disorders, 22(5-6), 471-485, 2006; Crumley et al. Psychology and Aging, 29(2), 250-263, 2014), recent work continues to offer little resolution. This review provides both quantitative and qualitative synthesis of research conducted since the last comprehensive review in 2006, with the aim of identifying reasons for these discrepancies that might provide fruitful avenues for future exploration. Meta-analysis found a small but significant association between SCCs and objective cognitive function, although it was limited by large heterogeneity between studies and evidence of potential publication bias. Often, assessments of SCCs and objective cognitive function were brief or not formally validated. However, studies that employed more comprehensive SCC measures tended to find that SCCs were associated independently with both objective cognitive function and depressive symptoms. Further explicit investigation of how assessment measures relate to reports of SCCs, and the validity of the proposed 'compensation theory' of SCC aetiology, is recommended.

Multicollision attack on CBC-MAC, EMAC, and XCBC-MAC of AES-128 algorithm

NASA Astrophysics Data System (ADS)

Brolin Sihite, Alfonso; Hayat Susanti, Bety

2017-10-01

A Message Authentication Codes (MAC) can be constructed based on a block cipher algorithm. CBC-MAC, EMAC, and XCBC-MAC constructions are some of MAC schemes that used in the hash function. In this paper, we do multicollision attack on CBC-MAC, EMAC, and XCBC-MAC construction which uses AES-128 block cipher algorithm as basic construction. The method of multicollision attack utilizes the concept of existential forgery on CBC-MAC. The results show that the multicollision can be obtained easily in CBC-MAC, EMAC, and XCBC-MAC construction.

Behavioral and Psychological Symptoms Impact Clinical Competence in Alzheimer’s Disease

PubMed Central

Bertrand, Elodie; van Duinkerken, Eelco; Landeira-Fernandez, J.; Dourado, Marcia C. N.; Santos, Raquel L.; Laks, Jerson; Mograbi, Daniel C.

2017-01-01

Decision-making is considered a fundamental aspect of personal autonomy and can be affected in psychiatric and neurologic diseases. It has been shown that cognitive deficits in dementia impact negatively on decision-making. Moreover, studies highlighted impaired clinical competence in neuropsychiatric disorders, such as schizophrenia and bipolar disorder. In this context, the current study explored the relationship between behavioral and psychological symptoms of dementia (BPSD) and clinical competence, especially the capacity to consent to treatment, in Alzheimer’s disease (AD). Seventy-one patients with mild to moderate AD participated, completing assessments for capacity to consent to treatment, general cognition and neuropsychiatric disturbances. For each neuropsychiatric symptom, patients with and without the particular disturbance were compared on the different subscales of the MacArthur Competence Tool for Treatment (MacCAT-T; Understanding, Appreciation, Reasoning and Expression). The results showed that patients presenting delusions, as well as apathetic patients, had a lower ability to express a clear treatment choice compared to patients without these symptoms. By contrast, patients with dysphoria/depression had higher scores on this variable. Additionally, AD patients with euphoria had more difficulties discussing consequences of treatment alternatives compared to patients without this disturbance. None of the differences were confounded by global cognition. There were no between-group differences in clinical decision-making for patients with hallucinations, agitation/aggression, anxiety, irritability, disinhibition and aberrant motor behavior. These findings highlight the importance of taking BPSD into account when assessing decision-making capacity, especially clinical competence, in AD. Furthermore, reducing BPSD may lead to better clinical competence in patients with AD, as well as to improvements in patients and caregivers’ quality of life. PMID:28670272

A Rehabilitation Protocol for Empowering Spatial Orientation in MCI. A Pilot Study.

PubMed

Gadler, Erminia; Grassi, Alessandra; Riva, Giuseppe

2009-01-01

Spatial navigation is among the first cognitive functions to be impaired in Alzheimer's disease [1] and deficit in this domain is detectable earlier in patients with Mild Cognitive Impairment [2]. Since efficacy of cognitive training in persons with MCI was successfully assessed [3], we developed a multitasking training protocol using virtual environments for stimulating attention, perception and visuo-spatial cognition in order to empower spatial orientation in MCI. Two healthy elders were exposed to the training over a period of four weeks and both showed improved performances in attention and orientation after the end of the intervention.

Boron delivery with liposomes for boron neutron capture therapy (BNCT): biodistribution studies in an experimental model of oral cancer demonstrating therapeutic potential.

PubMed

Heber, Elisa M; Kueffer, Peter J; Lee, Mark W; Hawthorne, M Frederick; Garabalino, Marcela A; Molinari, Ana J; Nigg, David W; Bauer, William; Hughes, Andrea Monti; Pozzi, Emiliano C C; Trivillin, Verónica A; Schwint, Amanda E

2012-05-01

Boron neutron capture therapy (BNCT) combines selective accumulation of (10)B carriers in tumor tissue with subsequent neutron irradiation. We previously demonstrated the therapeutic efficacy of BNCT in the hamster cheek pouch oral cancer model. Optimization of BNCT depends largely on improving boron targeting to tumor cells. Seeking to maximize the potential of BNCT for the treatment for head and neck cancer, the aim of the present study was to perform boron biodistribution studies in the oral cancer model employing two different liposome formulations that were previously tested for a different pathology, i.e., in experimental mammary carcinoma in BALB/c mice: (1) MAC: liposomes incorporating K[nido-7-CH(3)(CH(2))(15)-7,8-C(2)B(9)H(11)] in the bilayer membrane and encapsulating a hypertonic buffer, administered intravenously at 6 mg B per kg body weight, and (2) MAC-TAC: liposomes incorporating K[nido-7-CH(3)(CH(2))(15)-7,8-C(2)B(9)H(11)] in the bilayer membrane and encapsulating a concentrated aqueous solution of the hydrophilic species Na(3) [ae-B(20)H(17)NH(3)], administered intravenously at 18 mg B per kg body weight. Samples of tumor, precancerous and normal pouch tissue, spleen, liver, kidney, and blood were taken at different times post-administration and processed to measure boron content by inductively coupled plasma mass spectrometry. No ostensible clinical toxic effects were observed with the selected formulations. Both MAC and MAC-TAC delivered boron selectively to tumor tissue. Absolute tumor values for MAC-TAC peaked to 66.6 ± 16.1 ppm at 48 h and to 43.9 ± 17.6 ppm at 54 h with very favorable ratios of tumor boron relative to precancerous and normal tissue, making these protocols particularly worthy of radiobiological assessment. Boron concentration values obtained would result in therapeutic BNCT doses in tumor without exceeding radiotolerance in precancerous/normal tissue at the thermal neutron facility at RA-3.

Boron delivery with liposomes for boron neutron capture therapy (BNCT): biodistribution studies in an experimental model of oral cancer demonstrating therapeutic potential

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

David W. Nigg

2012-05-01

Boron neutron capture therapy (BNCT) combines selective accumulation of 10B carriers in tumor tissue with subsequent neutron irradiation. We previously demonstrated the therapeutic efficacy of BNCT in the hamster cheek pouch oral cancer model. Optimization of BNCT depends largely on improving boron targeting to tumor cells. Seeking to maximize the potential of BNCT for the treatment for head and neck cancer, the aim of the present study was to perform boron biodistribution studies in the oral cancer model employing two different liposome formulations that were previously tested for a different pathology, i.e., in experimental mammary carcinoma in BALB/c mice: (1)more » MAC: liposomes incorporating K[nido-7-CH3(CH2)15-7,8-C2B9H11] in the bilayer membrane and encapsulating a hypertonic buffer, administered intravenously at 6 mg B per kg body weight, and (2) MAC-TAC: liposomes incorporating K[nido-7-CH3(CH2)15-7,8-C2B9H11] in the bilayer membrane and encapsulating a concentrated aqueous solution of the hydrophilic species Na3 [ae-B20H17NH3], administered intravenously at 18 mg B per kg body weight. Samples of tumor, precancerous and normal pouch tissue, spleen, liver, kidney, and blood were taken at different times post-administration and processed to measure boron content by inductively coupled plasma mass spectrometry. No ostensible clinical toxic effects were observed with the selected formulations. Both MAC and MAC-TAC delivered boron selectively to tumor tissue. Absolute tumor values for MAC-TAC peaked to 66.6 {+-} 16.1 ppm at 48 h and to 43.9 {+-} 17.6 ppm at 54 h with very favorable ratios of tumor boron relative to precancerous and normal tissue, making these protocols particularly worthy of radiobiological assessment. Boron concentration values obtained would result in therapeutic BNCT doses in tumor without exceeding radiotolerance in precancerous/normal tissue at the thermal neutron facility at RA-3.« less

Increasing the quantity and quality of searching for current best evidence to answer clinical questions: protocol and intervention design of the MacPLUS FS Factorial Randomized Controlled Trials.

PubMed

Agoritsas, Thomas; Iserman, Emma; Hobson, Nicholas; Cohen, Natasha; Cohen, Adam; Roshanov, Pavel S; Perez, Miguel; Cotoi, Chris; Parrish, Rick; Pullenayegum, Eleanor; Wilczynski, Nancy L; Iorio, Alfonso; Haynes, R Brian

2014-09-20

Finding current best evidence for clinical decisions remains challenging. With 3,000 new studies published every day, no single evidence-based resource provides all answers or is sufficiently updated. McMaster Premium LiteratUre Service--Federated Search (MacPLUS FS) addresses this issue by looking in multiple high quality resources simultaneously and displaying results in a one-page pyramid with the most clinically useful at the top. Yet, additional logistical and educational barriers need to be addressed to enhance point-of-care evidence retrieval. This trial seeks to test three innovative interventions, among clinicians registered to MacPLUS FS, to increase the quantity and quality of searching for current best evidence to answer clinical questions. In a user-centered approach, we designed three interventions embedded in MacPLUS FS: (A) a web-based Clinical Question Recorder; (B) an Evidence Retrieval Coach composed of eight short educational videos; (C) an Audit, Feedback and Gamification approach to evidence retrieval, based on the allocation of 'badges' and 'reputation scores.' We will conduct a randomized factorial controlled trial among all the 904 eligible medical doctors currently registered to MacPLUS FS at the hospitals affiliated with McMaster University, Canada. Postgraduate trainees (n=429) and clinical faculty/staff (n=475) will be randomized to each of the three following interventions in a factorial design (AxBxC). Utilization will be continuously recorded through clinicians’ accounts that track logins and usage, down to the level of individual keystrokes. The primary outcome is the rate of searches per month per user during the six months of follow-up. Secondary outcomes, measured through the validated Impact Assessment Method questionnaire, include: utility of answers found (meeting clinicians’ information needs), use (application in practice), and perceived usefulness on patient outcomes. Built on effective models for the point-of-care teaching, these interventions approach evidence retrieval as a clinical skill. If effective, they may offer the opportunity to enhance it for a large audience, at low cost, providing better access to relevant evidence across many top EBM resources in parallel. ClinicalTrials.Gov NCT02038439.

Cognitive Communications Protocols for SATCOM

DTIC Science & Technology

2017-10-20

both inadvertent Radio Frequency Interference (RFI) and deliberate jammers. Cognitive satellite and space communications strategies based on the... communications protocols for satellite and space communications with possible broad applications in defense, homeland-security as well as consumer...proposed WACR as the basis for future space communication systems that will offer significant benefits to national war‐fighting and peacekeeping

SMAC: A soft MAC to reduce control overhead and latency in CDMA-based AMI networks

DOE PAGES

Garlapati, Shravan; Kuruganti, Teja; Buehrer, Michael R.; ...

2015-10-26

The utilization of state-of-the-art 3G cellular CDMA technologies in a utility owned AMI network results in a large amount of control traffic relative to data traffic, increases the average packet delay and hence are not an appropriate choice for smart grid distribution applications. Like the CDG, we consider a utility owned cellular like CDMA network for smart grid distribution applications and classify the distribution smart grid data as scheduled data and random data. Also, we propose SMAC protocol, which changes its mode of operation based on the type of the data being collected to reduce the data collection latency andmore » control overhead when compared to 3G cellular CDMA2000 MAC. The reduction in the data collection latency and control overhead aids in increasing the number of smart meters served by a base station within the periodic data collection interval, which further reduces the number of base stations needed by a utility or reduces the bandwidth needed to collect data from all the smart meters. The reduction in the number of base stations and/or the reduction in the data transmission bandwidth reduces the CAPital EXpenditure (CAPEX) and OPerational EXpenditure (OPEX) of the AMI network. Finally, the proposed SMAC protocol is analyzed using markov chain, analytical expressions for average throughput and average packet delay are derived, and simulation results are also provided to verify the analysis.« less

Low-cost Cognitive Electronics Technology for Enhanced Communications and Situational Awareness for Networks of Small Unmanned Aerial Vehicles (UAV)

DTIC Science & Technology

2013-03-01

series of checkpoints in a complex route network,” while observing standard traffic etiquette and regulations [17]. The rules for the 2012 RoboCup...structure or protocols above the PHY. To support AVEP operation, we developed a packet structure based on the transmission control protocol (TCP...Control Protocol .” 1981. [37] F. Ge, Q. Chen, Y. Wang, C. W. Bostian, T. W. Rondeau, and B. Le, “Cognitive radio: from spectrum sharing to adaptive

Awake craniotomy anesthetic management using dexmedetomidine, propofol, and remifentanil

PubMed Central

Prontera, Andrea; Baroni, Stefano; Marudi, Andrea; Valzania, Franco; Feletti, Alberto; Benuzzi, Francesca; Bertellini, Elisabetta; Pavesi, Giacomo

2017-01-01

Introduction Awake craniotomy allows continuous monitoring of patients’ neurological functions during open surgery. Anesthesiologists have to sedate patients in a way so that they are compliant throughout the whole surgical procedure, nevertheless maintaining adequate analgesia and anxiolysis. Currently, the use of α2-receptor agonist dexmedetomidine as the primary hypnotic–sedative medication is increasing. Methods Nine patients undergoing awake craniotomy were treated with refined monitored anesthesia care (MAC) protocol consisting of a combination of local anesthesia without scalp block, low-dose infusion of dexmedetomidine, propofol, and remifentanil, without the need of airways management. Results The anesthetic protocol applied in our study has the advantage of decreasing the dose of each drug and thus reducing the occurrence of side effects. All patients had smooth and rapid awakenings. The brain remained relaxed during the entire procedure. Conclusion In our experience, this protocol is safe and effective during awake brain surgery. Nevertheless, prospective randomized trials are necessary to confirm the optimal anesthetic technique to be used. PMID:28424537

Awake craniotomy anesthetic management using dexmedetomidine, propofol, and remifentanil.

PubMed

Prontera, Andrea; Baroni, Stefano; Marudi, Andrea; Valzania, Franco; Feletti, Alberto; Benuzzi, Francesca; Bertellini, Elisabetta; Pavesi, Giacomo

2017-01-01

Awake craniotomy allows continuous monitoring of patients' neurological functions during open surgery. Anesthesiologists have to sedate patients in a way so that they are compliant throughout the whole surgical procedure, nevertheless maintaining adequate analgesia and anxiolysis. Currently, the use of α2-receptor agonist dexmedetomidine as the primary hypnotic-sedative medication is increasing. Nine patients undergoing awake craniotomy were treated with refined monitored anesthesia care (MAC) protocol consisting of a combination of local anesthesia without scalp block, low-dose infusion of dexmedetomidine, propofol, and remifentanil, without the need of airways management. The anesthetic protocol applied in our study has the advantage of decreasing the dose of each drug and thus reducing the occurrence of side effects. All patients had smooth and rapid awakenings. The brain remained relaxed during the entire procedure. In our experience, this protocol is safe and effective during awake brain surgery. Nevertheless, prospective randomized trials are necessary to confirm the optimal anesthetic technique to be used.

C-MAC compared with direct laryngoscopy for intubation in patients with cervical spine immobilization: A manikin trial.

PubMed

Smereka, Jacek; Ladny, Jerzy R; Naylor, Amanda; Ruetzler, Kurt; Szarpak, Lukasz

2017-08-01

The aim of this study was to compare C-MAC videolaryngoscopy with direct laryngoscopy for intubation in simulated cervical spine immobilization conditions. The study was designed as a prospective randomized crossover manikin trial. 70 paramedics with <5years of medical experience participated in the study. The paramedics attempted to intubate manikins in 3 airway scenarios: normal airway without cervical immobilization (Scenario A); manual inline cervical immobilization (Scenario B); cervical immobilization using cervical extraction collar (Scenario C). Scenario A: Nearly all participants performed successful intubations with both MAC and C-MAC on the first attempt (95.7% MAC vs. 100% C-MAC), with similar intubation times (16.5s MAC vs. 18s C-MAC). Scenario B: The results with C-MAC were significantly better than those with MAC (p<0.05) for the time of intubation (23 s MAC vs. 19 s C-MAC), success of the first intubation attempt (88.6% MAC vs. 100% C-MAC), Cormack-Lehane grade, POGO score, severity of dental compression, device difficulty score, and preferred airway device. Scenario C: The results with C-MAC were significantly better than those with MAC (p<0.05) for all the analysed variables: success of the first attempt (51.4% MAC vs. 100% C-MAC), overall success rate, intubation time (27 s MAC vs. 20.5 s C-MAC), Cormack-Lehane grade, POGO score, dental compression, device difficulty score and the preferred airway device. The C-MAC videolaryngoscope is an excellent alternative to the MAC laryngoscope for intubating manikins with cervical spine immobilization. Copyright © 2017 Elsevier Inc. All rights reserved.

Cognition in depression: Can we THINC-it better?

PubMed

Baune, Bernhard T; Malhi, Gin S; Morris, Grace; Outhred, Tim; Hamilton, Amber; Das, Pritha; Bassett, Darryl; Berk, Michael; Boyce, Philip; Lyndon, Bill; Mulder, Roger; Parker, Gordon; Singh, Ajeet B

2018-01-01

Cognitive compromise is a common experience for patients with depression and other mood disorders. Depressed patients sustain deficits in working memory and attentional distortions in emotional processing and negative attention biases, which may contribute to maintaining their depressive state. The Mood Assessment and Classification (MAC) Committee comprised academic psychiatrists with clinical expertise in the management of mood disorders. The independently convened committee met to discuss contentious aspects of mood disorders diagnosis and assessment with the express aim of informing clinical practice and future research. The Committee specifically identified cognition as an important aspect for clinicians to consider in the context of depression and mood disorders. This article highlights some of the barriers to assessment and proposes tools that have the potential to be implemented in clinical practice. The conclusions drawn within this article are based on expert opinion. We have noted the limitations of the literature that informs this opinion. As cognitive ability has been closely linked to patients' ability to achieve functional recovery, it is imperative that clinicians are able to identify patients with cognitive deficits and are equipped with tools to conduct effective cognitive assessments. Examining cognitive factors may generate a deeper understanding of the pathogenesis of depression and mood disorders which can ultimately be used to inform treatment. Copyright © 2017 Elsevier B.V. All rights reserved.

Effects of a Commercial Drink on Acceleration Tolerance and Cognitive Performance

DTIC Science & Technology

2009-11-01

funded by a $120,000 grant from Coca - Cola Company, Atlanta GA. The authors wish to thank Mr. Mac Baker, Capt Julia McGregor, Mr. Tom Beltran, and Mr...recommendation or endorsement of the Coca Cola Company or the product tested. v Approved for public release; distribution unlimited; Approved by 311 th...drink (Full Throttle®, made by the Coca - Cola Company, at volumes equating to a caffeine dose of 5 mg caffeine per kg of body weight), an uncaffeinated

Sero-Diagnosis of Mycobacterium avium Complex Lung Disease Using Serum Immunoglobulin A Antibody against Glycopeptidolipid Antigen in Taiwan

PubMed Central

Wang, Jann-Tay; Jou, Ruwen; Wang, Jann-Yuan; Kobayashi, Kazuo; Lai, Hsin-Chih; Yu, Chong-Jen; Lee, Li-Na; Luh, Kwen-Tay

2013-01-01

Background Lung disease (LD) due to non-tuberculous mycobacteria is an important clinical concern. Mycobacterium avium complex (MAC) is one of the most common causative agents but the diagnosis of MAC-LD remains challenging. Detection of serum IgA antibody against MAC glycopeptidolipid (GPL) has recently been shown to improve the diagnosis of MAC-LD, but has yet to be validated worldwide. Methods This prospective study was conducted in a tertiary referral center in northern Taiwan and enrolled patients with MAC-LD, MAC contamination, other lung diseases, and control subjects. Serum immunoglobulin A (IgA) antibody against MAC-GPL was detected in the participants and its specificity and sensitivity was assessed. Results There were 56 patients with MAC-LD, 11 with MAC contamination, 13 M. kansasii-LD, 26 LD due to rapidly-growing mycobacteria (RGM), 48 pulmonary tuberculosis, and 42 household contacts of patients with TB. Patients with MAC-LD were older and 32% of them had an underlying co-morbidity. By logistic regression, serum MAC-GPL IgA level was an independent predictor of MAC-LD among the study subjects and those with culture-positive specimens for MAC. By the receiver operating characteristic curve, serum MAC-GPL IgA had a good power to discriminate MAC-LD from MAC contamination. Under the optimal cut-off value of 0.73 U/mL, its sensitivity and specificity were 60% and 91%, respectively. Among MAC-LD patients, presence of co-morbidity was associated with MAC-GPL <0.73 U/ml in logistic regression analysis. Conclusions Measurement of serum anti-MAC-GPL IgA level is useful for the diagnosis of MAC-LD. However, its implement in clinical practice for immuno-compromised hosts needs careful consideration. PMID:24260398

Design, Development, and Demonstration of a Prognostic and Diagnostics Health Monitoring System for the CROWS Platform

DTIC Science & Technology

2010-06-01

automatically appended onto the data packet by the CC2420 transceiver. The frame control field (FCF), data sequence number, and frame check sequence (FCS...by the CC2420 over the MAC protocol data unit (MPDU), i.e., the length field is not part of the FCS. This field is automatically generated and...verified by the CC2420 hardware when the AUTOCRC control bit is set in the MODEMCTRL0 control register’s field . If the FCS check indicates that a data

Underwater acoustic wireless sensor networks: advances and future trends in physical, MAC and routing layers.

PubMed

Climent, Salvador; Sanchez, Antonio; Capella, Juan Vicente; Meratnia, Nirvana; Serrano, Juan Jose

2014-01-06

This survey aims to provide a comprehensive overview of the current research on underwater wireless sensor networks, focusing on the lower layers of the communication stack, and envisions future trends and challenges. It analyzes the current state-of-the-art on the physical, medium access control and routing layers. It summarizes their security threads and surveys the currently proposed studies. Current envisioned niches for further advances in underwater networks research range from efficient, low-power algorithms and modulations to intelligent, energy-aware routing and medium access control protocols.

Examining the Effect of Organizational Roles in Shaping Network Traffic Activity

DTIC Science & Technology

2012-08-01

absolute value, and are presented in Table 3. Role Correlation Feature Admin 0.3004 bpp 0.2845 portsPerFlow 0.2063 addrDist -0.1869...OS Correlation Feature XP 0.4783 notTcpUdp 0.2867 addrDist -0.2389 bpp 0.1933 protocol -0.1852 flowInt Windows 7 0.3884 portDist 0.2367...addrDist 0.2001 direction 0.1751 bpp 0.1653 portsPerFlow Mac -0.2376 notTcpUdp 0.1978 UDP 0.1885 duration -0.1783 addrDist -0.1736 countEmpties

Effects of weight training on cognitive functions in elderly with Alzheimer's disease

PubMed Central

Vital, Thays Martins; Hernández, Salma S. Soleman; Pedroso, Renata Valle; Teixeira, Camila Vieira Ligo; Garuffi, Marcelo; Stein, Angelica Miki; Costa, José Luiz Riani; Stella, Florindo

2012-01-01

Deterioration in cognitive functions is characteristic in Alzheimer's disease (AD) and may be associated with decline in daily living activities with consequent reduced quality of life. Objective To analyze weight training effects on cognitive functions in elderly with AD. Subjects 34 elderly with AD were allocated into two groups: Training Group (TG) and Social Gathering Group (SGG). Methods Global cognitive status was determined using the Mini-Mental State Exam. Specific cognitive functions were measured using the Brief Cognitive Battery, Clock Drawing Test and Verbal Fluency Test. The protocols were performed three times a week, one hour per session. The weight training protocol consisted of three sets of 20 repetitions, with two minutes of rest between sets and exercises. The activities proposed for the SGG were not systematized and aimed at promoting social interaction among patients. The statistical analyses were performed with the U Mann Whitney and Wilcoxon tests for group comparisons. All analyses were considered statistically significant at a p-value of 0.05. Results There were no significant differences associated to the effects of the practice of weight training on cognition in AD patients. Conclusion In this study, no improvement in cognitive functions was evident in elderly with AD who followed a low intensity resistance exercise protocol. Thus, future studies could evaluate the effect of more intense exercise programs. PMID:29213805

Promoting Wired Links in Wireless Mesh Networks: An Efficient Engineering Solution

PubMed Central

Barekatain, Behrang; Raahemifar, Kaamran; Ariza Quintana, Alfonso; Triviño Cabrera, Alicia

2015-01-01

Wireless Mesh Networks (WMNs) cannot completely guarantee good performance of traffic sources such as video streaming. To improve the network performance, this study proposes an efficient engineering solution named Wireless-to-Ethernet-Mesh-Portal-Passageway (WEMPP) that allows effective use of wired communication in WMNs. WEMPP permits transmitting data through wired and stable paths even when the destination is in the same network as the source (Intra-traffic). Tested with four popular routing protocols (Optimized Link State Routing or OLSR as a proactive protocol, Dynamic MANET On-demand or DYMO as a reactive protocol, DYMO with spanning tree ability and HWMP), WEMPP considerably decreases the end-to-end delay, jitter, contentions and interferences on nodes, even when the network size or density varies. WEMPP is also cost-effective and increases the network throughput. Moreover, in contrast to solutions proposed by previous studies, WEMPP is easily implemented by modifying the firmware of the actual Ethernet hardware without altering the routing protocols and/or the functionality of the IP/MAC/Upper layers. In fact, there is no need for modifying the functionalities of other mesh components in order to work with WEMPPs. The results of this study show that WEMPP significantly increases the performance of all routing protocols, thus leading to better video quality on nodes. PMID:25793516

Performance Analysis of the IEEE 802.11p Multichannel MAC Protocol in Vehicular Ad Hoc Networks

PubMed Central

2017-01-01

Vehicular Ad Hoc Networks (VANETs) employ multichannel to provide a variety of safety and non-safety applications, based on the IEEE 802.11p and IEEE 1609.4 protocols. The safety applications require timely and reliable transmissions, while the non-safety applications require efficient and high throughput. In the IEEE 1609.4 protocol, operating interval is divided into alternating Control Channel (CCH) interval and Service Channel (SCH) interval with an identical length. During the CCH interval, nodes transmit safety-related messages and control messages, and Enhanced Distributed Channel Access (EDCA) mechanism is employed to allow four Access Categories (ACs) within a station with different priorities according to their criticality for the vehicle’s safety. During the SCH interval, the non-safety massages are transmitted. An analytical model is proposed in this paper to evaluate performance, reliability and efficiency of the IEEE 802.11p and IEEE 1609.4 protocols. The proposed model improves the existing work by taking serval aspects and the character of multichannel switching into design consideration. Extensive performance evaluations based on analysis and simulation help to validate the accuracy of the proposed model and analyze the capabilities and limitations of the IEEE 802.11p and IEEE 1609.4 protocols, and enhancement suggestions are given. PMID:29231882

Performance Analysis of the IEEE 802.11p Multichannel MAC Protocol in Vehicular Ad Hoc Networks.

PubMed

Song, Caixia

2017-12-12

Vehicular Ad Hoc Networks (VANETs) employ multichannel to provide a variety of safety and non-safety applications, based on the IEEE 802.11p and IEEE 1609.4 protocols. The safety applications require timely and reliable transmissions, while the non-safety applications require efficient and high throughput. In the IEEE 1609.4 protocol, operating interval is divided into alternating Control Channel (CCH) interval and Service Channel (SCH) interval with an identical length. During the CCH interval, nodes transmit safety-related messages and control messages, and Enhanced Distributed Channel Access (EDCA) mechanism is employed to allow four Access Categories (ACs) within a station with different priorities according to their criticality for the vehicle's safety. During the SCH interval, the non-safety massages are transmitted. An analytical model is proposed in this paper to evaluate performance, reliability and efficiency of the IEEE 802.11p and IEEE 1609.4 protocols. The proposed model improves the existing work by taking serval aspects and the character of multichannel switching into design consideration. Extensive performance evaluations based on analysis and simulation help to validate the accuracy of the proposed model and analyze the capabilities and limitations of the IEEE 802.11p and IEEE 1609.4 protocols, and enhancement suggestions are given.

The Montreal Cognitive Assessment is superior to National Institute of Neurological Disease and Stroke-Canadian Stroke Network 5-minute protocol in predicting vascular cognitive impairment at 1 year.

PubMed

Dong, YanHong; Xu, Jing; Chan, Bernard Poon-Lap; Seet, Raymond Chee Seong; Venketasubramanian, Narayanaswamy; Teoh, Hock Luen; Sharma, Vijay Kumar; Chen, Christopher Li-Hsian

2016-04-12

The predictive ability of National Institute of Neurological Disease and Stroke-Canadian Stroke Network (NINDS-CSN) 5-minute protocol and Montreal Cognitive Assessment (MoCA) administered sub-acutely and at the convalescent phase after stroke for significant vascular cognitive impairment (VCI) at 1 year is unknown. We compared prognostic values of these tests. Patients with ischemic stroke and transient ischemic attack (TIA) received MoCA sub-acutely (within 2 weeks) and 3-6 months after stroke followed by a formal neuropsychological evaluation at 1 year. The total score of NINDS-CSN 5-minutes protocol was derived from MoCA. Moderate-severe VCI was defined as neuropsychological impairment in ≥ 3 domains. Area under the receiver operating characteristic curve (AUC) analyses were conducted to establish the optimal cutoff points and discriminatory properties of the MoCA and NINDS-CSN 5-minute protocol in detecting moderate-severe VCI. Four hundre patients were recruited at baseline. Of these, 291 received a formal neuropsychological assessment 1 year after stroke. 19% patients had moderate-severe VCI. The MoCA was superior to the NINDS-CSN 5-minute protocol [sub-acute AUCs: 0.89 vs 0.80, p < 0.01; 3-6 months AUCs: 0.90 vs 0.83, p < 0.01] in predicting for moderate-severe VCI at 1 year. At respective cutoff points, MoCA had significantly higher sensitivity than the NINDS-CSN 5-minute protocol at baseline (p = 0.01) and 3-6 months (p = 0.04). MoCA administered sub-acutely and 3-6 months after stroke is superior to the NINDS-CSN 5-minute protocol in predicting moderate-severe VCI at 1 year.

[Cognitive therapy of trauma related guilt in patients with PTSD].

PubMed

Popiel, Agnieszka

2014-01-01

Various aspects of guilt are frequent problems of patients suffering from PTSD, though they have been included into the diagnostic criteria for PTSD just in the present version DSM-5. Some studies indicate limitation of effectiveness of exposure therapy in PTSD patients with predominant emotions of anger or guilt. The aim of this paper is to present cognitive conceptualization of guilt in PTSD proposed by Kubany, and a treatment protocol resulting from this conceptualization. The clinical application of the protocol is illustrated with preliminary results of systematic observation of 8 patients with moderate to severe PTSD who were treated with cognitive therapy for guilt followed by a standard prolonged exposure protocol. The cognitive therapy of guilt can be a valuable supplement for treatment of PTSD. This protocol can also be an inspiration for therapists working with patients with dysfunctional guilt as a problem in other than PTSD disorders--like depression or adjustment disorders. In discussion the place of guilt in treatment according to different (PE-Foa et al.; CPT-Resick et al.; CT-Ehlers and Clark) trauma focused therapy approaches is addressed, and the need for further studies is underlined.

Bulk Data Dissemination in Low Power Sensor Networks: Present and Future Directions

PubMed Central

Xu, Zhirong; Hu, Tianlei; Song, Qianshu

2017-01-01

Wireless sensor network-based (WSN-based) applications need an efficient and reliable data dissemination service to facilitate maintenance, management and data distribution tasks. As WSNs nowadays are becoming pervasive and data intensive, bulk data dissemination protocols have been extensively studied recently. This paper provides a comprehensive survey of the state-of-the-art bulk data dissemination protocols. The large number of papers available in the literature propose various techniques to optimize the dissemination protocols. Different from the existing survey works which separately explores the building blocks of dissemination, our work categorizes the literature according to the optimization purposes: Reliability, Scalability and Transmission/Energy efficiency. By summarizing and reviewing the key insights and techniques, we further discuss on the future directions for each category. Our survey helps unveil three key findings for future direction: (1) The recent advances in wireless communications (e.g., study on cross-technology interference, error estimating codes, constructive interference, capture effect) can be potentially exploited to support further optimization on the reliability and energy efficiency of dissemination protocols; (2) Dissemination in multi-channel, multi-task and opportunistic networks requires more efforts to fully exploit the spatial-temporal network resources to enhance the data propagation; (3) Since many designs incur changes on MAC layer protocols, the co-existence of dissemination with other network protocols is another problem left to be addressed. PMID:28098830

HIV and Cognitive Impairment in Clinical Practice: The Evaluation of a Stepwise Screening Protocol in Relation to Clinical Outcomes and Management.

PubMed

Hakkers, Charlotte S; Kraaijenhof, Jordan M; van Oers-Hazelzet, Esther B; Visser-Meily, Anne J M A; Hoepelman, Andy I M; Arends, Joop E; Barth, Roos E

2017-09-01

Neurocognitive impairment (NCI) is an increasingly important comorbidity in an ageing HIV+ population. Despite the lack of available treatment modalities, screening for NCI is recommended. In the UMC Utrecht, yearly NCI screening is done using the Montreal Cognitive Assessment (MoCA) tool and the HIV Dementia Scale (HDS). The aim of this study was to evaluate this screening protocol in relation to clinical outcomes and management. A retrospective cohort study was performed in suppressed adult HIV+ patients. Apart from the MoCa and the HDS, the Utrecht Scale for Evaluation of Rehabilitation-Participation (USER-P) and the Hospital Anxiety and Depression Scale (HADS) were performed. Patients scoring below average on cognitive screening tests or with subjective cognitive complaints were further evaluated using a standardized protocol, including optimizing cART and checking for somatic disorders. In patients with cognitive complaints and participation restrictions, cognitive rehabilitation was proposed. Two hundred eighty-six patients were screened. The vast majority were MSM with an average age of 49 years. One hundred forty-four out of 286 patients (50%) had an abnormal test score and/or had subjective cognitive complaints. Restrictions in participation were present in 23% of patients. Six patients on Efavirenz switched their regimes, as this drug is known for its potential central nervous system (CNS) side effects. A depressive component was present in 58 patients (40%). Five patients had a clinical relevant laboratory abnormality. Moreover, six patients were referred for cognitive rehabilitation, which resulted in a 100% success rate in set goals in the five evaluable patients. Although the protocol was not fully adhered to in all patients, it did result in detectable underlying causes of NCI in 59% of patients, and 21% was referred for further treatment. Moreover, cognitive rehabilitation appears to be a very successful intervention for patients with NCI who experience subjective complaints and participation restrictions.

Time and Energy Efficient Relay Transmission for Multi-Hop Wireless Sensor Networks.

PubMed

Kim, Jin-Woo; Barrado, José Ramón Ramos; Jeon, Dong-Keun

2016-06-27

The IEEE 802.15.4 standard is widely recognized as one of the most successful enabling technologies for short range low rate wireless communications and it is used in IoT applications. It covers all the details related to the MAC and PHY layers of the IoT protocol stack. Due to the nature of IoT, the wireless sensor networks are autonomously self-organized networks without infrastructure support. One of the issues in IoT is the network scalability. To address this issue, it is necessary to support the multi-hop topology. The IEEE 802.15.4 network can support a star, peer-to-peer, or cluster-tree topology. One of the IEEE 802.15.4 topologies suited for the high predictability of performance guarantees and energy efficient behavior is a cluster-tree topology where sensor nodes can switch off their transceivers and go into a sleep state to save energy. However, the IEEE 802.15.4 cluster-tree topology may not be able to provide sufficient bandwidth for the increased traffic load and the additional information may not be delivered successfully. The common drawback of the existing approaches is that they do not address the poor bandwidth utilization problem in IEEE 802.15.4 cluster-tree networks, so it is difficult to increase the network performance. Therefore, to solve this problem in this paper we study a relay transmission protocol based on the standard protocol in the IEEE 802.15.4 MAC. In the proposed scheme, the coordinators can relay data frames to their parent devices or their children devices without contention and can provide bandwidth for the increased traffic load or the number of devices. We also evaluate the performance of the proposed scheme through simulation. The simulation results demonstrate that the proposed scheme can improve the reliability, the end-to-end delay, and the energy consumption.

Time and Energy Efficient Relay Transmission for Multi-Hop Wireless Sensor Networks

PubMed Central

Kim, Jin-Woo; Barrado, José Ramón Ramos; Jeon, Dong-Keun

2016-01-01

The IEEE 802.15.4 standard is widely recognized as one of the most successful enabling technologies for short range low rate wireless communications and it is used in IoT applications. It covers all the details related to the MAC and PHY layers of the IoT protocol stack. Due to the nature of IoT, the wireless sensor networks are autonomously self-organized networks without infrastructure support. One of the issues in IoT is the network scalability. To address this issue, it is necessary to support the multi-hop topology. The IEEE 802.15.4 network can support a star, peer-to-peer, or cluster-tree topology. One of the IEEE 802.15.4 topologies suited for the high predictability of performance guarantees and energy efficient behavior is a cluster-tree topology where sensor nodes can switch off their transceivers and go into a sleep state to save energy. However, the IEEE 802.15.4 cluster-tree topology may not be able to provide sufficient bandwidth for the increased traffic load and the additional information may not be delivered successfully. The common drawback of the existing approaches is that they do not address the poor bandwidth utilization problem in IEEE 802.15.4 cluster-tree networks, so it is difficult to increase the network performance. Therefore, to solve this problem in this paper we study a relay transmission protocol based on the standard protocol in the IEEE 802.15.4 MAC. In the proposed scheme, the coordinators can relay data frames to their parent devices or their children devices without contention and can provide bandwidth for the increased traffic load or the number of devices. We also evaluate the performance of the proposed scheme through simulation. The simulation results demonstrate that the proposed scheme can improve the reliability, the end-to-end delay, and the energy consumption. PMID:27355952

Role of ATP binding and hydrolysis in assembly of MacAB-TolC macrolide transporter

PubMed Central

Lu, Shuo; Zgurskaya, Helen I.

2012-01-01

Summary MacB is a founding member of the Macrolide Exporter family of transporters belonging to the ATP-Binding Cassette superfamily. These proteins are broadly represented in genomes of both gram-positive and gram-negative bacteria and are implicated in virulence and protection against antibiotics and peptide toxins. MacB transporter functions together with MacA, a periplasmic membrane fusion protein, which stimulates MacB ATPase. In gram-negative bacteria, MacA is believed to couple ATP hydrolysis to transport of substrates across the outer membrane through a TolC-like channel. In this study, we report a real-time analysis of concurrent ATP hydrolysis and assembly of MacAB-TolC complex. MacB binds nucleotides with a low millimolar affinity and fast on- and off-rates. In contrast, MacA-MacB complex is formed with a nanomolar affinity, which further increases in the presence of ATP. Our results strongly suggest that association between MacA and MacB is stimulated by ATP binding to MacB but remains unchanged during ATP hydrolysis cycle. We also found that the large periplasmic loop of MacB plays the major role in coupling reactions separated in two different membranes. This loop is required for MacA-dependent stimulation of MacB ATPase and at the same time, contributes to recruitment of TolC into a trans-envelope complex. PMID:23057817

Underwater Wireless Sensor Networks: how do acoustic propagation models impact the performance of higher-level protocols?

PubMed

Llor, Jesús; Malumbres, Manuel P

2012-01-01

Several Medium Access Control (MAC) and routing protocols have been developed in the last years for Underwater Wireless Sensor Networks (UWSNs). One of the main difficulties to compare and validate the performance of different proposals is the lack of a common standard to model the acoustic propagation in the underwater environment. In this paper we analyze the evolution of underwater acoustic prediction models from a simple approach to more detailed and accurate models. Then, different high layer network protocols are tested with different acoustic propagation models in order to determine the influence of environmental parameters on the obtained results. After several experiments, we can conclude that higher-level protocols are sensitive to both: (a) physical layer parameters related to the network scenario and (b) the acoustic propagation model. Conditions like ocean surface activity, scenario location, bathymetry or floor sediment composition, may change the signal propagation behavior. So, when designing network architectures for UWSNs, the role of the physical layer should be seriously taken into account in order to assert that the obtained simulation results will be close to the ones obtained in real network scenarios.

Underwater Wireless Sensor Networks: How Do Acoustic Propagation Models Impact the Performance of Higher-Level Protocols?

PubMed Central

Llor, Jesús; Malumbres, Manuel P.

2012-01-01

Several Medium Access Control (MAC) and routing protocols have been developed in the last years for Underwater Wireless Sensor Networks (UWSNs). One of the main difficulties to compare and validate the performance of different proposals is the lack of a common standard to model the acoustic propagation in the underwater environment. In this paper we analyze the evolution of underwater acoustic prediction models from a simple approach to more detailed and accurate models. Then, different high layer network protocols are tested with different acoustic propagation models in order to determine the influence of environmental parameters on the obtained results. After several experiments, we can conclude that higher-level protocols are sensitive to both: (a) physical layer parameters related to the network scenario and (b) the acoustic propagation model. Conditions like ocean surface activity, scenario location, bathymetry or floor sediment composition, may change the signal propagation behavior. So, when designing network architectures for UWSNs, the role of the physical layer should be seriously taken into account in order to assert that the obtained simulation results will be close to the ones obtained in real network scenarios. PMID:22438712

The role of premorbid adjustment in schizophrenia: Focus on cognitive remediation outcome.

PubMed

Buonocore, Mariachiara; Bosinelli, Francesca; Bechi, Margherita; Spangaro, Marco; Piantanida, Marco; Cocchi, Federica; Bianchi, Laura; Guglielmino, Carmelo; Mastromatteo, Antonella Rita; Cavallaro, Roberto; Bosia, Marta

2018-02-19

Premorbid adjustment has been associated with several outcomes in schizophrenia and has been proposed as an index of cognitive reserve. This study aims to comprehensively analyse the relation between premorbid adjustment and clinical, neurocognitive, socio-cognitive and functional assessments, as well as to investigate the effect of premorbid adjustment on cognitive improvements after a cognitive remediation therapy protocol. Seventy-nine clinically stabilised outpatients with schizophrenia underwent a combined intervention consisting of cognitive remediation therapy added to standard rehabilitation therapy. All patients were assessed at baseline for psychopathology, premorbid adjustment, intellectual level, cognition and functioning. Cognitive evaluations were also repeated after the intervention. At baseline, significant correlations were observed between premorbid adjustment and working memory. The global cognitive improvement after treatment was significantly predicted by age and premorbid adjustment. This study confirms the association between premorbid adjustment and cognitive impairment and is the first to highlight the possible role of premorbid adjustment on the capacity to recover from cognitive deficits through a cognitive remediation therapy protocol. The data suggest that cognitive remediation may be particularly effective for people in the early course and that the assessment of premorbid adjustment could be of value to design individualised interventions.

Development of an algorithm for production of inactivated arbovirus antigens in cell culture

PubMed Central

Goodman, C.H.; Russell, B.J.; Velez, J.O.; Laven, J.J.; Nicholson, W.L; Bagarozzi, D.A.; Moon, J.L.; Bedi, K.; Johnson, B.W.

2015-01-01

Arboviruses are medically important pathogens that cause human disease ranging from a mild fever to encephalitis. Laboratory diagnosis is essential to differentiate arbovirus infections from other pathogens with similar clinical manifestations. The Arboviral Diseases Branch (ADB) reference laboratory at the CDC Division of Vector-Borne Diseases (DVBD) produces reference antigens used in serological assays such as the virus-specific immunoglobulin M antibody-capture enzyme-linked immunosorbent assay (MAC-ELISA). Antigen production in cell culture has largely replaced the use of suckling mice; however, the methods are not directly transferable. The development of a cell culture antigen production algorithm for nine arboviruses from the three main arbovirus families, Flaviviridae, Togaviridae, and Bunyaviridae, is described here. Virus cell culture growth and harvest conditions were optimized, inactivation methods were evaluated, and concentration procedures were compared for each virus. Antigen performance was evaluated by the MAC-ELISA at each step of the procedure. The antigen production algorithm is a framework for standardization of methodology and quality control; however, a single antigen production protocol was not applicable to all arboviruses and needed to be optimized for each virus. PMID:25102428

Feasibility and first results of a group program to increase the frequency of cognitively stimulating leisure activities in people with mild cognitive impairment (AKTIVA-MCI)

PubMed Central

Tesky, Valentina A; Köbe, Theresa; Witte, A Veronica; Flöel, Agnes; Schuchardt, Jan Philipp; Hahn, Andreas; Pantel, Johannes

2017-01-01

AKTIVA-MCI is a program for patients with mild cognitive impairment (MCI) that aims to enhance participation in cognitively stimulating leisure activities. Participation in cognitively stimulating activities seems to be a potential strategy for people with MCI delaying cognitive decline for a while. In total, 35 MCI patients were enrolled in the pilot study of whom 29 completed the whole program (16 female, 71.1±7.5 years; Mini Mental Status Examination score: 28±2.2). Daily activity protocols were used to measure the frequency of participation in cognitively stimulating activities during the program (12 sessions). Additional standardized psychometric tests and questionnaires were used to assess cognition, mood, and subjective memory decline. Analyses of the daily activity protocols showed that during the intervention participants increased the frequency of several cognitively stimulating leisure activities. Comparison of pre-post data indicates no changes in cognitive status, mood, and subjective memory decline. These findings indicate that the program is suitable for patients with MCI. PMID:28979108

Pilot Testing a Cognitive-Behavioral Protocol on Psychosocial Predictors of Exercise, Nutrition, Weight, and Body Satisfaction Changes in a College-Level Health-Related Fitness Course

ERIC Educational Resources Information Center

Annesi, James J.; Howton, Amy; Johnson, Ping H.; Porter, Kandice J.

2015-01-01

Objective: Small-scale pilot testing of supplementing a required college health-related fitness course with a cognitive-behavioral exercise-support protocol (The Coach Approach). Participants: Three classes were randomly assigned to Usual processes (n = 32), Coach Approach-supplemented: Mid-size Groups (n = 32), and Coach Approach-supplemented:…

Effects of childhood trauma exposure and cortisol levels on cognitive functioning among breast cancer survivors.

PubMed

Kamen, Charles; Scheiber, Caroline; Janelsins, Michelle; Jo, Booil; Shen, Hanyang; Palesh, Oxana

2017-10-01

Cognitive functioning difficultiesin breast cancer patients receiving chemotherapy are common, but not all women experience these impairments. Exposure to childhood trauma may impair cognitive functioning following chemotherapy, and these impairments may be mediated by dysregulation of hypothalamic-pituitary-adrenal (HPA) axis function and cortisol slope. This study evaluated the association between childhood trauma exposure, cortisol, and cognition in a sample of breast cancer survivors. 56 women completed measures of trauma exposure (the Traumatic Events Survey), salivary cortisol, and self-reported cognitive functioning (the Functional Assessment of Cancer Therapy - Cognitive). We examined correlations between childhood trauma exposure and cognitive functioning, then used linear regression to control for factors associated with cognition (age, education, time since chemotherapy, depression, anxiety, and insomnia), and the MacArthur approach to test whether cortisol levels mediated the relationship between trauma and cognitive functioning. 57.1% of the sample had experienced at least one traumatic event in childhood, with 19.6% of the sample witnessing a serious injury, 17.9% experiencing physical abuse, and 14.3% experiencing sexual abuse. Childhood trauma exposure and cognitive functioning were moderately associated (r=-0.29). This association remained even when controlling for other factors associated with cognition; the final model explained 47% of the variance in cognitive functioning. The association between childhood trauma and cognitive functioning was mediated by steeper cortisol slope (partial r=0.35, p=0.02). Childhood trauma exposure is associated with self-reported cognitive functioning among breast cancer survivors and is mediated by cortisol dysregulation. Trauma should be considered, among other factors, in programs aiming to address cognition in this population. Copyright © 2017 Elsevier Ltd. All rights reserved.

The effect of relational training on intelligence quotient: a case study.

PubMed

Vizcaíno-Torres, Rosa M; Ruiz, Francisco J; Luciano, Carmen; López-López, Juan C; Barbero-Rubio, Adrián; Gil, Enriquel

2015-01-01

Relational training protocols based on Relational Frame Theory (RFT) are showing promising results in increasing intelligence quotient. This case study aimed at analyzing the effect of a training protocol in fluency and flexibility in relational responding on intelligence quotient with a 4-year-old child. The child’s cognitive and psychomotor development was evaluated before and after the implementation of the training protocol using the McCarthy’s Aptitudes and Psychomotricity Scale (MSCA). The training protocol consisted of a multiple-exemplar-training (MET) in relational framing in accordance with COORDINATION (Phases 1 and 2), OPPOSITION (Phase 3 and 4), and COMPARISON (Phases 5 and 6). The MET protocol was implemented in approximately 12 hours throughout five and one half months. The training was effective in establishing relational responding in OPPOSITION and COMPARISON frames as well as in promoting fluency and flexibility in all the three types of trained relations. After this training, the child showed an increase above 1.5 SD in the General Cognitive Index of the MSCA (from 106 to 131). This case study adds further empirical evidence of the potential of RFT training to improve cognitive abilities and intelligence.

The Combined Utility of a Brief Functional Measure and Performance-Based Screening Test for Case Finding of Cognitive Impairment in Primary Healthcare.

PubMed

Chan, Qun Lin; Shaik, Muhammad Amin; Xu, Jing; Xu, Xin; Chen, Christopher Li-Hsian; Dong, YanHong

2016-04-01

Use of a total risk score (TRS) based on vascular and sociodemographic risk factors has been recommended to identify patients at risk of cognitive impairment. Moreover, combining screening tests has been reported to improve positive predictive values (PPV) for case finding of cognitive impairment. We investigated the utility of the conjunctive combination of the informant-based AD8 and the performance-based National Institute of Neurological Disorders and Stroke-Canadian Stroke Network (NINDS-CSN) 5-minute protocol for the detection of cognitive impairment, defined by a clinical dementia rating (CDR) score ≥0.5, in patients at risk of cognitive impairment (TRS ≥3). Participants were recruited from 2 primary healthcare centers in Singapore and received the AD8, Montreal Cognitive Assessment, Mini-Mental State Examination, CDR, and a formal neuropsychological test battery. The scores for NINDS-CSN 5-minute protocol were extracted from the Montreal Cognitive Assessment items. Area under the receiver operating characteristics curve analyses were conducted to determine the discriminant indices of the screening instruments, the conjunctive combination (ie, screened positive on both tests), and the compensatory combination (ie, screened positive in either of or both tests). A total of 309 participants were recruited of whom 78.7% (n = 243) had CDR = 0 and 21.3% (n = 66) had CDR ≥0.5. The conjunctive combination of AD8 and NINDS-CSN 5-minute protocol achieved excellent PPV and acceptable sensitivity (PPV 91.7%, sensitivity 73.3%). The conjunctive combination of the AD8 and NINDS-CSN 5-minute protocol is brief and accurate, and hence, suitable for case finding of cognitive impairment (CDR ≥0.5) in patients screened positive on the TRS in primary healthcare centers. Copyright © 2016. Published by Elsevier Inc.

Measuring the Effect of Soil-Transmitted Helminth Infections on Cognitive Function in Children: Systematic Review and Critical Appraisal of Evidence.

PubMed

Owada, Kei; Nielsen, Mark; Lau, Colleen L; Clements, Archie C A; Yakob, Laith; Soares Magalhães, Ricardo J

2017-01-01

Recently the role of soil-transmitted helminth (STH) infections in children's cognitive developmental impairment has been under scrutiny. We conducted a systematic review of the evidence for associations between STH infections and cognitive function of children using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses protocol. We aimed to identify the domains of cognitive function in three age strata (<24months, 24-59months and ≥60months) and critically appraise the general design protocol of the studies, with a focus on the cognitive function measurement tools used. A total of 42 papers fulfilled the inclusion criteria, including 10 studies from a recent Cochrane review. Our findings demonstrate variation in tested domains, lack of consistency in the use of measurement tools and analysis of results. Cognitive function measures in children aged under 59months have been mainly limited to domains of gross motor, fine motor and language skills, whereas in children aged 60months and above most studies tested domains such as memory and processing speed. Even within the same age group the results on the association between STH infections and measures of cognitive development were often conflicting. The current study highlights the need for methodological consensus in the use of measurement tools and data analysis protocols if the effect of STH infections on cognitive function domains in children is to be correctly established. This will be an imperative next step to generate conclusive evidence of the role of STH infections in cognitive development in children. Copyright © 2017 Elsevier Ltd. All rights reserved.

Cognitive LF-Ant: a novel protocol for healthcare wireless sensor networks.

PubMed

Sousa, Marcelo; Lopes, Waslon; Madeiro, Francisco; Alencar, Marcelo

2012-01-01

In this paper, the authors present the Cognitive LF-Ant protocol for emergency reporting in healthcare wireless sensor networks. The protocol is inspired by the natural behaviour of ants and a cognitive component provides the capabilities to dynamically allocate resources, in accordance with the emergency degree of each patient. The intra-cluster emergency reporting is inspired by the different capabilities of leg-manipulated ants. The inter-cluster reporting is aided by the cooperative modulation diversity with spectrum sensing, which can detect new emergency reporting requests and forward them. Simulations results show the decrease of average delay time as the probability of opportunistic access increases, which privileges the emergency reporting related to the patients with higher priority of resources' usage. Furthermore, the packet loss rate is decreased by the use of cooperative modulation diversity with spectrum sensing.

Cognitive LF-Ant: A Novel Protocol for Healthcare Wireless Sensor Networks

PubMed Central

Sousa, Marcelo; Lopes, Waslon; Madeiro, Francisco; Alencar, Marcelo

2012-01-01

In this paper, the authors present the Cognitive LF-Ant protocol for emergency reporting in healthcare wireless sensor networks. The protocol is inspired by the natural behaviour of ants and a cognitive component provides the capabilities to dynamically allocate resources, in accordance with the emergency degree of each patient. The intra-cluster emergency reporting is inspired by the different capabilities of leg-manipulated ants. The inter-cluster reporting is aided by the cooperative modulation diversity with spectrum sensing, which can detect new emergency reporting requests and forward them. Simulations results show the decrease of average delay time as the probability of opportunistic access increases, which privileges the emergency reporting related to the patients with higher priority of resources' usage. Furthermore, the packet loss rate is decreased by the use of cooperative modulation diversity with spectrum sensing. PMID:23112610

Treating women with perinatal mood and anxiety disorders (PMADs) with a hybrid cognitive behavioural and art therapy treatment (CB-ART).

PubMed

Sarid, Orly; Cwikel, Julie; Czamanski-Cohen, Johanna; Huss, Ephrat

2017-02-01

This paper presents an overview of a combined, evaluated protocol, cognitive behavioural and art therapy treatment (CB-ART), for the treatment of women with perinatal mood and anxiety disorders (PMADs). The protocol integrates cognitive behavioural interventions and art therapy. CB-ART focuses on changing distressing image, symptom or memory (ISM) that interferes with functioning. The method directs clients to identify compositional elements that characterize their stressful ISM and to alter the element in their imagination, in bodily sensations and on the page. Examples are provided to illustrate the therapeutic process.

Inhibition of misleading heuristics as a core mechanism for typical cognitive development: evidence from behavioural and brain-imaging studies.

PubMed

Borst, Grégoire; Aïte, Ania; Houdé, Olivier

2015-04-01

Cognitive development is generally conceived as incremental with knowledge of increasing complexity acquired throughout childhood and adolescence. However, several studies have now demonstrated not only that infants possess complex cognitive abilities but also that older children, adolescents, and adults tend to make systematic errors even in simple logical reasoning tasks. Therefore, one of the main issues for any theory of typical cognitive development is to provide an explanation of why at some age and in some contexts children, adolescents, and adults do not express a knowledge or cognitive principle that they already acquired when they were younger. In this review, we present convergent behavioural and neurocognitive evidence that cognitive development is more similar to a non-linear dynamic system than to a linear, stage-like system. In this theoretical framework, errors can emerge in problems similar to the ones infants or young children were succeeding when older children, adolescents, and adults rely on a misleading heuristic rather than on the correct logical algorithm to solve such problems. And the core mechanism for overcoming these errors is inhibitory control (i.e. the ability to inhibit the misleading heuristics). Therefore, typical cognitive development relies not only on the ability to acquire knowledge of incremental complexity but also to inhibit previously acquired knowledge. © 2015 The Authors. Developmental Medicine & Child Neurology © 2015 Mac Keith Press.

RACOON: a multiuser QoS design for mobile wireless body area networks.

PubMed

Cheng, Shihheng; Huang, Chingyao; Tu, Chun Chen

2011-10-01

In this study, Random Contention-based Resource Allocation (RACOON) medium access control (MAC) protocol is proposed to support the quality of service (QoS) for multi-user mobile wireless body area networks (WBANs). Different from existing QoS designs that focus on a single WBAN, a multiuser WBAN QoS should further consider both inter-WBAN interference and inter-WBAN priorities. Similar problems have been studied in both overlapped wireless local area networks (WLANs) and Bluetooth piconets that need QoS supports. However, these solutions are designed for non-medical transmissions that do not consider any priority scheme for medical applications. Most importantly, these studies focus on only static or low mobility networks. Network mobility of WBANs will introduce unnecessary inter-network collisions and energy waste, which are not considered by these solutions. The proposed multiuser-QoS protocol, RACOON, simultaneously satisfies the inter WBAN QoS requirements and overcomes the performance degradation caused by WBAN mobility. Simulation results verify that RACOON provides better latency and energy control, as compared with WBAN QoS protocols without considering the inter-WBAN requirements.

An Alpha and Theta Intensive and Short Neurofeedback Protocol for Healthy Aging Working-Memory Training

PubMed Central

Reis, Joana; Portugal, Ana Maria; Fernandes, Luís; Afonso, Nuno; Pereira, Mariana; Sousa, Nuno; Dias, Nuno S.

2016-01-01

The present study tested the effects of an intensive and short alpha and theta neurofeedback (NF) protocol in working memory (WM) performance in a healthy elder population and explored the effects of a multimodal approach, by supplementing NF with cognitive tasks. Participants were allocated to four groups: NF (N = 9); neurofeedback supplemented with cognitive training (NFCT) (N = 8); cognitive training (CT) (N = 7) and sham neurofeedback (Sham-NF) (N = 6). The intervention consisted in 30-min sessions for 8 days. The NF group presented post intervention increases of alpha and theta relative power as well as performance in the matrix rotation task. In addition, a successful up training of frontal theta showed positive correlation with an improvement of post-training alpha and a better performance in the matrix rotation task. The results presented herein suggest that an intensive and short NF protocol enables elders to learn alpha and theta self-modulation and already presents moderate improvements in cognition and basal EEG. Also, CT group showed moderate performance gains on the cognitive tasks used during the training sessions but no clear improvements on neurophysiology and behavioral measurements were observed. This study represents a first attempt to study the effects of an intensive and short NF protocol in WM performance of elders. The evidence presented here suggests that an intensive and short NF intervention could be a valid alternative for introduction of older populations to NF methodologies. PMID:27458369

Mental Fatigue and Physical and Cognitive Performance During a 2-Bout Exercise Test.

PubMed

Vrijkotte, Susan; Meeusen, Romain; Vandervaeren, Cloe; Buyse, Luk; Cutsem, Jeroen van; Pattyn, Nathalie; Roelands, Bart

2018-04-01

The 2-bout exercise protocol has been developed to diagnose nonfunctional overreaching and the "overtraining syndrome." It consists of 2 maximal exercise bouts separated by 4 hours. Mental fatigue negatively influences performance, but the effects of its occurrence during the 2-bout exercise protocol have never been investigated. The aim of this study was to examine whether mental fatigue (induced during the rest period) influences physical and cognitive performance during/after the second exercise bout of the 2-bout exercise protocol. Nine healthy, well-trained male cyclists participated in a single-blind, randomized, placebo-controlled crossover study. The intervention consisted of either 1.5-hour rest (control) or performing a computer-based Stroop task to induce mental fatigue. Cognitive (Eriksen Flanker task), physiological (lactate, maximum heart rate, and maximum wattage), and subjective data (mental fatigue-visual analog scale, Profile of Mood States, and rating of perceived exertion) were gathered. Ratings of fatigue, tension, and mental fatigue were affected in the mental fatigue condition (P < .05). Neither physiological nor cognitive differences were found between conditions. Ratings of mental fatigue were already affected after the first maximum exercise test (P < .05). Neither physical nor cognitive performance was affected by mental fatigue, but subjective ratings did reveal significant differences. It is recommended to exclude mentally challenging tasks during the 2-bout exercise protocol rest period to ascertain unaffected subjective test results. This study should be repeated in athletes diagnosed with nonfunctional overreaching/overtraining syndrome.

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

Yang Huayan; Yu Junping; Fu Guo

The interaction between integrin macrophage differentiation antigen associated with complement three receptor function (Mac-1) and intercellular adhesion molecule-1 (ICAM-1), which is controlled tightly by the ligand-binding activity of Mac-1, is central to the regulation of neutrophil adhesion in host defense. Several 'inside-out' signals and extracellular metal ions or antibodies have been found to activate Mac-1, resulting in an increased adhesiveness of Mac-1 to its ligands. However, the molecular basis for Mac-1 activation is not well understood yet. In this work, we have carried out a single-molecule study of Mac-1/ICAM-1 interaction force in living cells by atomic force microscopy (AFM). Ourmore » results showed that the binding probability and adhesion force of Mac-1 with ICAM-1 increased upon Mac-1 activation. Moreover, by comparing the dynamic force spectra of different Mac-1 mutants, we expected that Mac-1 activation is governed by the downward movement of its {alpha}7 helix.« less

SEAODV: A Security Enhanced AODV Routing Protocol for Wireless Mesh Networks

NASA Astrophysics Data System (ADS)

Li, Celia; Wang, Zhuang; Yang, Cungang

In this paper, we propose a Security Enhanced AODV routing protocol (SEAODV) for wireless mesh networks (WMN). SEAODV employs Blom's key pre-distribution scheme to compute the pairwise transient key (PTK) through the flooding of enhanced HELLO message and subsequently uses the established PTK to distribute the group transient key (GTK). PTK and GTK authenticate unicast and broadcast routing messages respectively. In WMN, a unique PTK is shared by each pair of nodes, while GTK is shared secretly between the node and all its one-hop neighbours. A message authentication code (MAC) is attached as the extension to the original AODV routing message to guarantee the message's authenticity and integrity in a hop-by-hop fashion. Security analysis and performance evaluation show that SEAODV is more effective in preventing identified routing attacks and outperforms ARAN and SAODV in terms of computation cost and route acquisition latency.

Underwater Acoustic Wireless Sensor Networks: Advances and Future Trends in Physical, MAC and Routing Layers

PubMed Central

Climent, Salvador; Sanchez, Antonio; Capella, Juan Vicente; Meratnia, Nirvana; Serrano, Juan Jose

2014-01-01

This survey aims to provide a comprehensive overview of the current research on underwater wireless sensor networks, focusing on the lower layers of the communication stack, and envisions future trends and challenges. It analyzes the current state-of-the-art on the physical, medium access control and routing layers. It summarizes their security threads and surveys the currently proposed studies. Current envisioned niches for further advances in underwater networks research range from efficient, low-power algorithms and modulations to intelligent, energy-aware routing and medium access control protocols. PMID:24399155

Sensium: an ultra-low-power wireless body sensor network platform: design & application challenges.

PubMed

Wong, A W; McDonagh, D; Omeni, O; Nunn, C; Hernandez-Silveira, M; Burdett, A J

2009-01-01

In this paper we present a system-on-chip for wireless body sensor networks, which integrates a transceiver, hardware MAC protocol, microprocessor, IO peripherals, memories, ADC and custom sensor interfaces. Addressing the challenges in the design, this paper will continue to discuss the issues in the applications of this technology to body worn monitoring for real-time measurement of ECG, heart rate, physical activity, respiration and/or skin temperature. Two application challenges are described; the real-time measurement of energy expenditure using the LifePebble, and; the development issues surrounding the 'Digital Patch'.

Average waiting time in FDDI networks with local priorities

NASA Technical Reports Server (NTRS)

Gercek, Gokhan

1994-01-01

A method is introduced to compute the average queuing delay experienced by different priority group messages in an FDDI node. It is assumed that no FDDI MAC layer priorities are used. Instead, a priority structure is introduced to the messages at a higher protocol layer (e.g. network layer) locally. Such a method was planned to be used in Space Station Freedom FDDI network. Conservation of the average waiting time is used as the key concept in computing average queuing delays. It is shown that local priority assignments are feasable specially when the traffic distribution is asymmetric in the FDDI network.

Analogy motor learning by young children: a study of rope skipping.

PubMed

Tse, Andy C Y; Fong, Shirley S M; Wong, Thomson W L; Masters, Rich

2017-03-01

Research in psychology suggests that provision of an instruction by analogy can enhance acquisition and understanding of knowledge. Limited research has been conducted to test this proposition in motor learning by children. The purpose of the present study was to examine the feasibility of analogy instructions in motor skill acquisition by children. Thirty-two children were randomly assigned to one of the two instruction protocols: analogy and explicit instruction protocols for a two-week rope skipping training. Each participant completed a pretest (Lesson 1), three practice sessions (Lesson 2-4), a posttest and a secondary task test (Lesson 5). Children in the analogy protocol displayed better rope skip performance than those in the explicit instruction protocol (p < .001). Moreover, a cognitive secondary task test indicated that children in the analogy protocol performed more effectively, whereas children in the explicit protocol displayed decrements in performance. Analogy learning may aid children to acquire complex motor skills, and have potential benefits related to reduced cognitive processing requirements.

Value of a quality assessment program in optimizing cryopreservation of peripheral blood mononuclear cells in a multicenter study.

PubMed

Aziz, Najib; Margolick, Joseph B; Detels, Roger; Rinaldo, Charles R; Phair, John; Jamieson, Beth D; Butch, Anthony W

2013-04-01

Cryopreservation of peripheral blood mononuclear cells (PBMC) allows assays of cellular function and phenotype to be performed in batches at a later time on PBMC at a central laboratory to minimize assay variability. The Multicenter AIDS Cohort Study (MACS) is an ongoing prospective study of the natural and treated history of human immunodeficiency virus (HIV) infection that stores cryopreserved PBMC from participants two times a year at four study sites. In order to ensure consistent recovery of viable PBMC after cryopreservation, a quality assessment program was implemented and conducted in the MACS over a 6-year period. Every 4 months, recently cryopreserved PBMC from HIV-1-infected and HIV-1-uninfected participants at each MACS site were thawed and evaluated. The median recoveries of viable PBMC for HIV-1-infected and -uninfected participants were 80% and 83%, respectively. Thawed PBMC from both HIV-1-infected and -uninfected participants mounted a strong proliferative response to phytohemagglutinin, with median stimulation indices of 84 and 120, respectively. Expression of the lymphocyte surface markers CD3, CD4, and CD8 by thawed PBMC was virtually identical to what was observed on cells measured in real time using whole blood from the same participants. Furthermore, despite overall excellent performance of the four participating laboratories, problems were identified that intermittently compromised the quality of cryopreserved PBMC, which could be corrected and monitored for improvement over time. Ongoing quality assessment helps laboratories improve protocols and performance on a real-time basis to ensure optimal cryopreservation of PBMC for future studies.

Quality testing of an innovative cascade separation system for multiple cell separation

NASA Astrophysics Data System (ADS)

Pierzchalski, Arkadiusz; Moszczynska, Aleksandra; Albrecht, Bernd; Heinrich, Jan-Michael; Tarnok, Attila

2012-03-01

Isolation of different cell types from mixed samples in one separation step by FACS is feasible but expensive and slow. It is cheaper and faster but still challenging by magnetic separation. An innovative bead-based cascade-system (pluriSelect GmbH, Leipzig, Germany) relies on simultaneous physical separation of different cell types. It is based on antibody-mediated binding of cells to beads of different size and isolation with sieves of different mesh-size. We validated pluriSelect system for single parameter (CD3) and simultaneous separation of CD3 and CD15 cells from EDTA blood-samples. Results were compared with those obtained by MACS (Miltenyi-Biotech) magnetic separation (CD3 separation). pluriSelect separation was done in whole blood, MACS on Ficoll gradient isolated leukocytes, according to the manufacturer's protocols. Isolated and residual cells were immunophenotyped (7-color 8-antibody panel (CD3; CD16/56; CD4; CD8; CD14; CD19; CD45; HLADR) on a CyFlowML flow cytometer (Partec GmbH). Cell count (Coulter), purity, yield and viability (7-AAD exclusion) were determined. There were no significant differences between both systems regarding purity (92-98%), yield (50-60%) and viability (92-98%) of isolated cells. PluriSelect separation was slightly faster than MACS (1.15 h versus 1.5h). Moreover, no preenrichment steps were necessary. In conclusion, pluriSelect is a fast, simple and gentle system for efficient simultaneous separation of two cell subpopulation directly from whole blood and can provide a simple alternative to FACS. The isolated cells can be used for further research applications.

The Marburg-Münster Affective Disorders Cohort Study (MACS): A quality assurance protocol for MR neuroimaging data.

PubMed

Vogelbacher, Christoph; Möbius, Thomas W D; Sommer, Jens; Schuster, Verena; Dannlowski, Udo; Kircher, Tilo; Dempfle, Astrid; Jansen, Andreas; Bopp, Miriam H A

2018-05-15

Large, longitudinal, multi-center MR neuroimaging studies require comprehensive quality assurance (QA) protocols for assessing the general quality of the compiled data, indicating potential malfunctions in the scanning equipment, and evaluating inter-site differences that need to be accounted for in subsequent analyses. We describe the implementation of a QA protocol for functional magnet resonance imaging (fMRI) data based on the regular measurement of an MRI phantom and an extensive variety of currently published QA statistics. The protocol is implemented in the MACS (Marburg-Münster Affective Disorders Cohort Study, http://for2107.de/), a two-center research consortium studying the neurobiological foundations of affective disorders. Between February 2015 and October 2016, 1214 phantom measurements have been acquired using a standard fMRI protocol. Using 444 healthy control subjects which have been measured between 2014 and 2016 in the cohort, we investigate the extent of between-site differences in contrast to the dependence on subject-specific covariates (age and sex) for structural MRI, fMRI, and diffusion tensor imaging (DTI) data. We show that most of the presented QA statistics differ severely not only between the two scanners used for the cohort but also between experimental settings (e.g. hardware and software changes), demonstrate that some of these statistics depend on external variables (e.g. time of day, temperature), highlight their strong dependence on proper handling of the MRI phantom, and show how the use of a phantom holder may balance this dependence. Site effects, however, do not only exist for the phantom data, but also for human MRI data. Using T1-weighted structural images, we show that total intracranial (TIV), grey matter (GMV), and white matter (WMV) volumes significantly differ between the MR scanners, showing large effect sizes. Voxel-based morphometry (VBM) analyses show that these structural differences observed between scanners are most pronounced in the bilateral basal ganglia, thalamus, and posterior regions. Using DTI data, we also show that fractional anisotropy (FA) differs between sites in almost all regions assessed. When pooling data from multiple centers, our data show that it is a necessity to account not only for inter-site differences but also for hardware and software changes of the scanning equipment. Also, the strong dependence of the QA statistics on the reliable placement of the MRI phantom shows that the use of a phantom holder is recommended to reduce the variance of the QA statistics and thus to increase the probability of detecting potential scanner malfunctions. Copyright © 2018 Elsevier Inc. All rights reserved.

Prognostic Comparison Between Mucinous and Nonmucinous Adenocarcinoma in Colorectal Cancer

PubMed Central

Park, Jong Seob; Huh, Jung Wook; Park, Yoon Ah; Cho, Yong Beom; Yun, Seong Hyeon; Kim, Hee Cheol; Lee, Woo Yong; Chun, Ho-Kyung

2015-01-01

Abstract Mucinous adenocarcinoma (MAC) is a histological subtype of colorectal cancer. The oncologic behavior of MAC differs from nonmucinous adenocarcinoma (non-MAC). Our aim in this study was to characterize patients with colorectal MAC through evaluation of a large, institutional-based cohort with long-term follow-up. A total of 6475 patients with stages I to III colorectal cancer who underwent radical surgery were enrolled from January 2000 to December 2010. Prognostic comparison between MAC (n = 274, 4.2%) and non-MAC was performed. The median follow-up period was 48.0 months. Patients with MAC were younger than those without MAC (P = 0.012) and had larger tumor size (P < 0.001), higher preoperative carcinoembryonic antigen (P < 0.001), higher pathologic T stage (P < 0.001), more right-sided colon cancer (49.3%, P < 0.001), and more frequent high-frequency microsatellite instability (10.2%, P < 0.001). Five-year disease-free survival (DFS) was 76.5% in the MAC group and 83.2% in the non-MAC group (P = 0.008), and 5-year overall survival was 81.4% versus 87.4%, respectively (P = 0.005). Mucinous histology (MAC vs non-MAC) in the entire cohort was not an independent prognostic factor of DFS but had a statistical tendency (P = 0.071). In subgroup analysis of colon cancer without rectal cancer, mucinous histology was an independent prognostic factor (P = 0.026). MAC was found at more advanced stage, located mainly at the right side and was an independent factor of survival in colon cancer. Because of the unique biological behavior of MAC, patients with MAC require special consideration during follow-up. PMID:25881840

A slotted access control protocol for metropolitan WDM ring networks

NASA Astrophysics Data System (ADS)

Baziana, P. A.; Pountourakis, I. E.

2009-03-01

In this study we focus on the serious scalability problems that many access protocols for WDM ring networks introduce due to the use of a dedicated wavelength per access node for either transmission or reception. We propose an efficient slotted MAC protocol suitable for WDM ring metropolitan area networks. The proposed network architecture employs a separate wavelength for control information exchange prior to the data packet transmission. Each access node is equipped with a pair of tunable transceivers for data communication and a pair of fixed tuned transceivers for control information exchange. Also, each access node includes a set of fixed delay lines for synchronization reasons; to keep the data packets, while the control information is processed. An efficient access algorithm is applied to avoid both the data wavelengths and the receiver collisions. In our protocol, each access node is capable of transmitting and receiving over any of the data wavelengths, facing the scalability issues. Two different slot reuse schemes are assumed: the source and the destination stripping schemes. For both schemes, performance measures evaluation is provided via an analytic model. The analytical results are validated by a discrete event simulation model that uses Poisson traffic sources. Simulation results show that the proposed protocol manages efficient bandwidth utilization, especially under high load. Also, comparative simulation results prove that our protocol achieves significant performance improvement as compared with other WDMA protocols which restrict transmission over a dedicated data wavelength. Finally, performance measures evaluation is explored for diverse numbers of buffer size, access nodes and data wavelengths.

Functional implications of an intermeshing cogwheel-like interaction between TolC and MacA in the action of macrolide-specific efflux pump MacAB-TolC.

PubMed

Xu, Yongbin; Song, Saemee; Moeller, Arne; Kim, Nahee; Piao, Shunfu; Sim, Se-Hoon; Kang, Mooseok; Yu, Wookyung; Cho, Hyun-Soo; Chang, Iksoo; Lee, Kangseok; Ha, Nam-Chul

2011-04-15

Macrolide-specific efflux pump MacAB-TolC has been identified in diverse gram-negative bacteria including Escherichia coli. The inner membrane transporter MacB requires the outer membrane factor TolC and the periplasmic adaptor protein MacA to form a functional tripartite complex. In this study, we used a chimeric protein containing the tip region of the TolC α-barrel to investigate the role of the TolC α-barrel tip region with regard to its interaction with MacA. The chimeric protein formed a stable complex with MacA, and the complex formation was abolished by substitution at the functionally essential residues located at the MacA α-helical tip region. Electron microscopic study delineated that this complex was made by tip-to-tip interaction between the tip regions of the α-barrels of TolC and MacA, which correlated well with the TolC and MacA complex calculated by molecular dynamics. Taken together, our results demonstrate that the MacA hexamer interacts with TolC in a tip-to-tip manner, and implies the manner by which MacA induces opening of the TolC channel.

Functional Implications of an Intermeshing Cogwheel-like Interaction between TolC and MacA in the Action of Macrolide-specific Efflux Pump MacAB-TolC*

PubMed Central

Xu, Yongbin; Song, Saemee; Moeller, Arne; Kim, Nahee; Piao, Shunfu; Sim, Se-Hoon; Kang, Mooseok; Yu, Wookyung; Cho, Hyun-Soo; Chang, Iksoo; Lee, Kangseok; Ha, Nam-Chul

2011-01-01

Macrolide-specific efflux pump MacAB-TolC has been identified in diverse Gram-negative bacteria including Escherichia coli. The inner membrane transporter MacB requires the outer membrane factor TolC and the periplasmic adaptor protein MacA to form a functional tripartite complex. In this study, we used a chimeric protein containing the tip region of the TolC α-barrel to investigate the role of the TolC α-barrel tip region with regard to its interaction with MacA. The chimeric protein formed a stable complex with MacA, and the complex formation was abolished by substitution at the functionally essential residues located at the MacA α-helical tip region. Electron microscopic study delineated that this complex was made by tip-to-tip interaction between the tip regions of the α-barrels of TolC and MacA, which correlated well with the TolC and MacA complex calculated by molecular dynamics. Taken together, our results demonstrate that the MacA hexamer interacts with TolC in a tip-to-tip manner, and implies the manner by which MacA induces opening of the TolC channel. PMID:21325274

[Cognitions in eating disorders and their assessment].

PubMed

Eiber, R; Mirabel-Sarron, C; Urdapilleta, I

2005-01-01

Cognitions are of crucial importance in the -aetiology and the maintenance of eating disorders. Dysfunctional cognitions in eating disorders are related to body image, self-esteem and feeding. The aim of this paper is to review the actual knowledge in this area. First, we will display -cognitive models in eating disorders. Cognitive factors in -eating disorders are logical errors, cognitive slippage and conceptual complexity. Eating disorder patients seem to have a deficient cognitive development. Some cognitive models stipulate that eating disorder patients may develop organised cognitive structures schemas concerning the issues of weight and its implications for the self. These schemas can account for the persistence and for the understanding the "choice of the eating disorder symptomatology. Cognitive pheno-mena of interest are self-schema, weight-related schema and weight-related self-schema. The maintenance model of ano-rexia nervosa argued that, initially there is an extreme need to control eating which is supported by low self-esteem. The maintenance of the disorder is reinforced by three mechanisms: dietary restriction enhances the sense of being in control; aspects of starvation encourage further dietary restriction; concerns about shape and weight encourage restriction. The development and maintenance of bulimic symptomatology are explained by placing a high value on attaining an idealised weight and body shape accompanied by inaccurate beliefs. The cognitive model of specific family of origin experiences puts forward the development of -maladaptative expectancies for eating and thinness. Second, we discuss distortions in information processing. a) In feeding laboratories, bulimics show a wide range of caloric intake and a disruption of circadian feeding patterns. In overeating bulimics, large meals occurred mainly during afternoon and evening with high fat and carbohydrate intake, but the majority of meals were of normal size and frequency. Responsivity to food cues indicates that bulimics were more responsive to sight, smell and taste of their favourite binge food, and a greater responsivity was associated with increasing -cue salience. Eating disorder patients appear to have internalised a mediated social rule concerning "good food" and make drastic selections thus removing the possibility of choice of foodstuffs. b) Experimental processes: temporal factors in the processing of threat seem to be of importance in patients with high levels of eating psychopathology. There is no evidence for preattentive processing biases among anorectics. Changes in information processing speed after treatment were not linked to treatment condition or treatment response. c) Judgement and emotions: in eating disorder patients, distortions of depressogenic nature are found that influence the cognitive style; thoughts about eating, weight and shape are characterised by negative affective tone; negative emotions could account for bulimic behaviour; anxiety and distress are correlated to thought control strategies. Information treating seems to be impaired in a non-homogeneous way. d) Cognitive schemas are seriously maladaptive and not well investigated. In eating disorder patients, core beliefs are absolute, unconditional and dichotomous cognitions about oneself and the world. There are only few studies in this field moreover showing controversial results. Core beliefs can explain links between personality disorders and eating psychopathology. Pathological core beliefs have to be taken in to account because they influence the outcome and the efficacy of cognitive behavioural therapy. Third, the last part of this paper summarises actually available rating scales eva-luating distorted cognitions in eating disorders. There are different methods for evaluation: specific and non-specific self-report questionnaires, thought-sampling procedures, -methods derived from cognitive psychology. The Mizes Anorectic Cognition questionnaire (MAC) is a well-known self-rating scale with good psychometric properties. The revised form of the MAC appears to be an improvement in the area of internal consistency, sensitivity, and reliability. It is obvious that there is no particular rating scale referring to specific cognitions on food. the main result of this literature review reflects that the cognitive treatment in eating disorders is altered in a specific way on an emotional basis and on self-representation.

Performance analysis of multi-radio routing protocol in cognitive radio ad hoc networks under different path failure rate

NASA Astrophysics Data System (ADS)

Che-Aron, Z.; Abdalla, A. H.; Abdullah, K.; Hassan, W. H.

2013-12-01

In recent years, Cognitive Radio (CR) technology has largely attracted significant studies and research. Cognitive Radio Ad Hoc Network (CRAHN) is an emerging self-organized, multi-hop, wireless network which allows unlicensed users to opportunistically access available licensed spectrum bands for data communication under an intelligent and cautious manner. However, in CRAHNs, a lot of failures can easily occur during data transmission caused by PU (Primary User) activity, topology change, node fault, or link degradation. In this paper, an attempt has been made to evaluate the performance of the Multi-Radio Link-Quality Source Routing (MR-LQSR) protocol in CRAHNs under different path failure rate. In the MR-LQSR protocol, the Weighted Cumulative Expected Transmission Time (WCETT) is used as the routing metric. The simulations are carried out using the NS-2 simulator. The protocol performance is evaluated with respect to performance metrics like average throughput, packet loss, average end-to-end delay and average jitter. From the simulation results, it is observed that the number of path failures depends on the PUs number and mobility rate of SUs (Secondary Users). Moreover, the protocol performance is greatly affected when the path failure rate is high, leading to major service outages.

Cerebral microbleeds, cognitive impairment, and MRI in patients with diabetes mellitus.

PubMed

Zhou, Hong; Yang, Juan; Xie, Peihan; Dong, Yulan; You, Yong; Liu, Jincai

2017-07-01

Cerebral microbleeds (CMBs), a typical imaging manifestation marker of sporadic cerebral small vessel disease, play a critical role in vascular cognitive impairment, which is often accompanied by diabetes mellitus (DM). Hence, CMBs may, in part, be responsible for the occurrence and development of cognitive impairment in patients with diabetes. Novel magnetic resonance imaging (MRI) sequences, such as susceptibility-weighted imaging and T2*-weighted gradient-echo, have the capability of noninvasively revealing CMBs in the brain. Moreover, a correlation between CMBs and cognitive impairment in patients with diabetes has been suggested in applications of functional MRI (fMRI). Since pathological changes in the brain occur prior to observable decline in cognitive function, neuroimaging may help predict the progression of cognitive impairment in diabetic patients. In this article, we review the detection of CMBs using MRI in diabetic patients exhibiting cognitive impairment. Future studies should emphasize the development and establishment of a novel MRI protocol, including fMRI, for diabetic patients with cognitive impairment to detect CMBs. A reliable MRI protocol would also be helpful in understanding the pathological mechanisms of cognitive impairment in this important patient population. Copyright © 2017. Published by Elsevier B.V.

Clinical Trials of Blood Pressure Lowering and Antihypertensive Medication: Is Cognitive Measurement State-of-the-Art?

PubMed

Elias, Merrill F; Torres, Rachael V; Davey, Adam

2018-05-07

Randomized controlled trials of blood pressure (BP) lowering and antihypertensive medication use on cognitive outcomes have often been disappointing, reporting mixed findings and small effect sizes. We evaluate the extent to which cognitive assessment protocols used in these trials approach state-of-the-art. Overall, we find that a primary focus on cognition and the systematic selection of cognitive outcomes across trials take a backseat to other trial goals. Twelve trials investigating change in cognitive functioning were examined and none met criteria for state-of-the-art assessment, including use of at least 4 tests indexing 2 cognitive domains. Four trials investigating incident dementia were also examined. Each trial used state-of-the-art diagnostic criteria to assess dementia, although follow-up periods were relatively short, with only 2 trials lasting for at least 3 years. Weaknesses in each trial may act to obscure or weaken the positive effects of BP lowering on cognitive functioning. Improving trial designs in terms of cognitive outcomes selected and length of follow-up periods employed could lead to more promising findings. We offer logical steps to achieve state-of-the-art assessment protocols, with examples, in hopes of improving future trials.

Validating the Manchester Acute Coronary Syndromes (MACS) and Troponin-only Manchester Acute Coronary Syndromes (T-MACS) rules for the prediction of acute myocardial infarction in patients presenting to the emergency department with chest pain.

PubMed

Greenslade, Jaimi H; Nayer, Robert; Parsonage, William; Doig, Shaela; Young, Joanna; Pickering, John W; Than, Martin; Hammett, Christopher; Cullen, Louise

2017-08-01

The Manchester Acute Coronary Syndromes (MACS) rule and the Troponin-only MACS (T-MACS) rule risk stratify patients with suspected acute coronary syndrome (ACS). This observational study sought to validate and compare the MACS and T-MACS rules for assessment of acute myocardial infarction (AMI). Prospectively collected data from twoEDs in Australia and New Zealand were analysed. Patients were assigned a probability of ACS based on the MACS and T-MACS rules, incorporating high-sensitivity troponin T, heart-type fatty acid-binding protein, ECG results and clinical symptoms. Patients were then deemed very low risk, low risk, intermediate or high risk if their MACS probability was less than 2%, between 2% and 5%, between 5% and 95% and greater than 95%, respectively. The primary endpoint was 30-day diagnosis of AMI. The secondary endpoint was 30-day major adverse cardiac event (MACE) including AMI, revascularisation or coronary stenosis (>70%). Sensitivity, specificity and predictive values were calculated to assess the accuracy of the MACS and T-MACS rules. Of the 1244 patients, 114 (9.2%) were diagnosed with AMI and 163 (13.1%) with MACE. The MACS and T-MACS rules categorised 133 (10.7%) and 246 (19.8%) patients, respectively, as very low risk and potentially suitable for early discharge from the ED. There was one false negative case for both rules making sensitivity 99.1% (95.2%-100%). MACS and T-MACS accurately risk stratify very low risk patients. The T-MACS rule would allow for more patients to be discharged early. The potential for missed MACE events means that further outpatient testing for coronary artery disease may be required for patients identified as very low risk. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Brazilian version of the Protocole Montréal d'Evaluation de la Communication (Protocole MEC): normative and reliability data.

PubMed

Fonseca, Rochele Paz; Joanette, Yves; Côté, Hélène; Ska, Bernadette; Giroux, Francine; Fachel, Jandyra Maria Guimarães; Damasceno Ferreira, Gabriela; Parente, Maria Alice de Mattos Pimenta

2008-11-01

The lack of standardized instruments to evaluate communication disorders related to the right hemisphere was verified. A new evaluation tool was developed: Protocole Montréal d'Evaluation de la Communication--Protocole MEC, adapted to Brazilian Portuguese--Bateria Montreal de Avaliação da Comunicação--Bateria MAC (Montreal Evaluation of Communication Battery). The purpose was to present stratified normative data by age and educational level, and to verify the reliability parameters of the MEC Battery. 300 individuals, between the ages of 19 and 75 years, and levels of formal education between 2 and 35 years, participated in this study. They were divided equally into six normative groups, according to three age categories (young adults, intermediary age, and seniors) and two educational levels (low and high). Two procedures were used to check reliability: Cronbach alpha and reliability between evaluators, Results were established at the 10th percentile, and an alert point per task for each normative group. Cronbach's alpha was, in general, between .70 and .90 and the average rate of agreement between evaluators varied from .62 to .94. Standards of age and education were established. The reliability of this instrument was verified. The psychometric legitimization of the MEC Battery will contribute to the diagnostic process for communicative disorders.

Clinical Applicability and Cutoff Values for an Unstructured Neuropsychological Assessment Protocol for Older Adults with Low Formal Education

PubMed Central

de Paula, Jonas Jardim; Bertola, Laiss; Ávila, Rafaela Teixeira; Moreira, Lafaiete; Coutinho, Gabriel; de Moraes, Edgar Nunes; Bicalho, Maria Aparecida Camargos; Nicolato, Rodrigo; Diniz, Breno Satler; Malloy-Diniz, Leandro Fernandes

2013-01-01

Background and Objectives The neuropsychological exam plays a central role in the assessment of elderly patients with cognitive complaints. It is particularly relevant to differentiate patients with mild dementia from those subjects with mild cognitive impairment. Formal education is a critical factor in neuropsychological performance; however, there are few studies that evaluated the psychometric properties, especially criterion related validity, neuropsychological tests for patients with low formal education. The present study aims to investigate the validity of an unstructured neuropsychological assessment protocol for this population and develop cutoff values for clinical use. Methods and Results A protocol composed by the Rey-Auditory Verbal Learning Test, Frontal Assessment Battery, Category and Letter Fluency, Stick Design Test, Clock Drawing Test, Digit Span, Token Test and TN-LIN was administered to 274 older adults (96 normal aging, 85 mild cognitive impairment and 93 mild Alzheimer`s disease) with predominantly low formal education. Factor analysis showed a four factor structure related to Executive Functions, Language/Semantic Memory, Episodic Memory and Visuospatial Abilities, accounting for 65% of explained variance. Most of the tests showed a good sensitivity and specificity to differentiate the diagnostic groups. The neuropsychological protocol showed a significant ecological validity as 3 of the cognitive factors explained 31% of the variance on Instrumental Activities of Daily Living. Conclusion The study presents evidence of the construct, criteria and ecological validity for this protocol. The neuropsychological tests and the proposed cutoff values might be used for the clinical assessment of older adults with low formal education. PMID:24066031

Hypothalamic-pituitary-adrenal axis physiology and cognitive control of behavior in stress inoculated monkeys.

PubMed

Parker, Karen J; Buckmaster, Christine L; Lindley, Steven E; Schatzberg, Alan F; Lyons, David M

2012-01-01

Monkeys exposed to stress inoculation protocols early in life subsequently exhibit diminished neurobiological responses to moderate psychological stressors and enhanced cognitive control of behavior during juvenile development compared to non-inoculated monkeys. The present experiments extended these findings and revealed that stress inoculated monkeys: (a) mount neurobiological responses equivalent to non-inoculated monkeys when the stressor is of sufficient intensity, and (b) continue to exhibit enhanced cognitive control as young adults compared to non-inoculated monkeys. These results suggest that stress inoculation protocols alter the appraisal of and response to moderate stressors as less threatening and permanently enhance cognitive control, at least through early adulthood. These data therefore support the notion that the stress inoculation phenotype reflects stress resilience rather than stress pathology.

Unified Protocol for the Transdiagnostic Treatment of Emotional Disorders: Protocol Development and Initial Outcome Data

ERIC Educational Resources Information Center

Ellard, Kristen K.; Fairholme, Christopher P.; Boisseau, Christina L.; Farchione, Todd J.; Barlow, David H.

2010-01-01

The Unified Protocol (UP) is a transdiagnostic, emotion-focused cognitive-behavioral treatment developed to be applicable across the emotional disorders. The UP consists of 4 core modules: increasing emotional awareness, facilitating flexibility in appraisals, identifying and preventing behavioral and emotional avoidance, and situational and…

Development and validation of a parent-report measure for detection of cognitive delay in infancy.

PubMed

Schafer, Graham; Genesoni, Lucia; Boden, Greg; Doll, Helen; Jones, Rosamond A K; Gray, Ron; Adams, Eleri; Jefferson, Ros

2014-12-01

To develop a brief, parent-completed instrument (ERIC - Early Report by Infant Caregivers) for detection of cognitive delay in 10- to 24-month-olds born preterm, or of low birthweight, or with perinatal complications, and to establish ERIC's diagnostic properties. Scores for ERIC were collected from the parents of 317 children meeting ≥inclusion criterion (birthweight <1500 g, gestational age <34 completed weeks, 5 min Apgar score <7, or presence of hypoxic-ischaemic encephalopathy) and no exclusion criteria. Children were assessed using a criterion score of below 80 on the Bayley Scales of Infant and Toddler Development-III cognitive scale. Items were retained according to their individual associations with delay. Sensitivity, specificity, and positive and negative predictive values were estimated and a truncated ERIC was developed for use in children <14 months old. ERIC correctly detected developmental delay in 17 out of 18 children in the sample, with 94.4% sensitivity, 76.9% specificity, 19.8% positive predictive value, 99.6% negative predictive value, 4.09 likelihood ratio positive, and 0.07 likelihood ratio negative. ERIC has potential value as a quickly administered diagnostic instrument for the absence of early cognitive delay in 10- to 24-month-old preterm infants and as a screen for cognitive delay. © 2014 Mac Keith Press.

Testing a "content meets process" model of depression vulnerability and rumination: Exploring the moderating role of set-shifting deficits.

PubMed

Vergara-Lopez, Chrystal; Lopez-Vergara, Hector I; Roberts, John E

2016-03-01

MacCoon and Newman's (2006) "content meets process" model posits that deficits in cognitive control make it difficult to disengage from negative cognitions caused by a negative cognitive style (NCS). The present study examined if the interactive effect of cognitive set-shifting abilities and NCS predicts rumination and past history of depression. Participants were 90 previously depressed individuals and 95 never depressed individuals. We administered three laboratory tasks that assess set-shifting: the Wisconsin Card-Sorting Task, the Emotional Card-Sorting Task, and the Internal Switch Task, and self-report measures of NCS and rumination. Shifting ability in the context of emotional distractors moderated the association between NCS and depressive rumination. Although previously depressed individuals had more NCS and higher trait rumination relative to never depressed individuals, shifting ability did not moderate the association between NCS and depression history. The cross-sectional correlational design cannot address the causal direction of effects. It is also not clear whether findings will generalize beyond college students. NCS was elevated in previously depressed individuals consistent with its theoretical role as trait vulnerability to the disorder. Furthermore, NCS may be particularly likely to trigger rumination among individuals with poor capacity for cognitive control in the context of emotional distraction. Copyright © 2015 Elsevier Ltd. All rights reserved.

Chemotherapy-Induced Cognitive Impairment: A Novel Prospective Study of the Cognitive Effects of Platinum Taxane-Based Chemotherapy in Ovarian Cancer Patients

DTIC Science & Technology

2017-09-01

post chemotherapy testing , completing all protocol-defined tests and procedures and are now off study. Two patients are currently undergoing treatment...and will complete post treatment testing within the upcoming weeks. The first patient enrolled onto this trial was unable to complete post treatment...completed post chemotherapy testing , completing all protocol-defined tests and procedures and are now off study. Two patients are currently

Differential learning abilities of 129T2/Sv and C57BL/6J mice as assessed in three water maze protocols.

PubMed

Wolff, Mathieu; Savova, Magdaléna; Malleret, Gaël; Segu, Louis; Buhot, Marie-Christine

2002-11-15

Knockout mice are generated by using ES cells from 129 mouse strains and are frequently backcrossed with other strains, like C57BL/6. It is important to characterise the physiological and, in particular, the behavioural profile of each strain in order to correctly analyse the functional contribution of a single gene mutation on the 'cognitive' phenotype. The present study compared 129T2/Sv (129) and C57BL/6J (C57) mice in three different spatial learning protocols in the water maze, using a hidden platform. In the 'standard' reference memory protocol, 129 and C57 attained an equivalent level of performance as assessed by accuracy in reaching the platform (path length), despite a faster swim speed exhibited by C57 mice. In a stepwise learning task, C57 mice showed poorer performances over all stages of learning. However they performed better than 129 in a massed learning protocol which taxes short-term memory, and in which they exhibited lower levels of perseveration. The results emphasize the importance of using various tasks differing in cognitive demand, but using the same experimental environment and motivation, in order to 1) evaluate strain- or mutation-dependent learning abilities, and 2) dissociate the roles played by cognitive and non-cognitive factors in the behavioural requirements of the tasks. Copyright 2002 Elsevier Science B.V.

The role of pre-morbid intelligence and cognitive reserve in predicting cognitive efficiency in a sample of Italian elderly.

PubMed

Caffò, Alessandro O; Lopez, Antonella; Spano, Giuseppina; Saracino, Giuseppe; Stasolla, Fabrizio; Ciriello, Giuseppe; Grattagliano, Ignazio; Lancioni, Giulio E; Bosco, Andrea

2016-12-01

Models of cognitive reserve in aging suggest that individual's life experience (education, working activity, and leisure) can exert a neuroprotective effect against cognitive decline and may represent an important contribution to successful aging. The objective of the present study is to investigate the role of cognitive reserve, pre-morbid intelligence, age, and education level, in predicting cognitive efficiency in a sample of healthy aged individuals and with probable mild cognitive impairment. Two hundred and eight aging participants recruited from the provincial region of Bari (Apulia, Italy) took part in the study. A battery of standardized tests was administered to them to measure cognitive reserve, pre-morbid intelligence, and cognitive efficiency. Protocols for 10 participants were excluded since they did not meet inclusion criteria, and statistical analyses were conducted on data from the remaining 198 participants. A path analysis was used to test the following model: age, education level, and intelligence directly influence cognitive reserve and cognitive efficiency; cognitive reserve mediates the influence of age, education level, and intelligence on cognitive efficiency. Cognitive reserve fully mediates the relationship between pre-morbid intelligence and education level and cognitive efficiency, while age maintains a direct effect on cognitive efficiency. Cognitive reserve appears to exert a protective effect regarding cognitive decline in normal and pathological populations, thus masking, at least in the early phases of neurodegeneration, the decline of memory, orientation, attention, language, and reasoning skills. The assessment of cognitive reserve may represent a useful evaluation supplement in neuropsychological screening protocols of cognitive decline.

Adaptive management of energy consumption, reliability and delay of wireless sensor node: Application to IEEE 802.15.4 wireless sensor node.

PubMed

Kone, Cheick Tidjane; Mathias, Jean-Denis; De Sousa, Gil

2017-01-01

Designing a Wireless Sensor Network (WSN) to achieve a high Quality of Service (QoS) (network performance and durability) is a challenging problem. We address it by focusing on the performance of the 802.15.4 communication protocol because the IEEE 802.15.4 Standard is actually considered as one of the reference technologies in WSNs. In this paper, we propose to control the sustainable use of resources (i.e., energy consumption, reliability and timely packet transmission) of a wireless sensor node equipped with photovoltaic cells by an adaptive tuning not only of the MAC (Medium Access Control) parameters but also of the sampling frequency of the node. To do this, we use one of the existing control approaches, namely the viability theory, which aims to preserve the functions and the controls of a dynamic system in a set of desirable states. So, an analytical model, describing the evolution over time of nodal resources, is derived and used by a viability algorithm for the adaptive tuning of the IEEE 802.15.4 MAC protocol. The simulation analysis shows that our solution allows ensuring indefinitely, in the absence of hardware failure, the operations (lifetime duration, reliability and timely packet transmission) of an 802.15.4 WSN and one can temporarily increase the sampling frequency of the node beyond the regular sampling one. This latter brings advantages for agricultural and environmental applications such as precision agriculture, flood or fire prevention. Main results show that our current approach enable to send more information when critical events occur without the node runs out of energy. Finally, we argue that our approach is generic and can be applied to other types of WSN.

MacA, a periplasmic membrane fusion protein of the macrolide transporter MacAB-TolC, binds lipopolysaccharide core specifically and with high affinity.

PubMed

Lu, Shuo; Zgurskaya, Helen I

2013-11-01

The Escherichia coli MacAB-TolC transporter has been implicated in efflux of macrolide antibiotics and secretion of enterotoxin STII. In this study, we found that purified MacA, a periplasmic membrane fusion protein, contains one tightly bound rough core lipopolysaccharide (R-LPS) molecule per MacA molecule. R-LPS was bound specifically to MacA protein with affinity exceeding that of polymyxin B. Sequence analyses showed that MacA contains two high-density clusters of positively charged amino acid residues located in the cytoplasmic N-terminal domain and the periplasmic C-terminal domain. Substitutions in the C-terminal cluster reducing the positive-charge density completely abolished binding of R-LPS. At the same time, these substitutions significantly reduced the functionality of MacA in the protection of E. coli against macrolides in vivo and in the in vitro MacB ATPase stimulation assays. Taken together, our results suggest that R-LPS or a similar glycolipid is a physiological substrate of MacAB-TolC.

MacA, a Periplasmic Membrane Fusion Protein of the Macrolide Transporter MacAB-TolC, Binds Lipopolysaccharide Core Specifically and with High Affinity

PubMed Central

Lu, Shuo

2013-01-01

The Escherichia coli MacAB-TolC transporter has been implicated in efflux of macrolide antibiotics and secretion of enterotoxin STII. In this study, we found that purified MacA, a periplasmic membrane fusion protein, contains one tightly bound rough core lipopolysaccharide (R-LPS) molecule per MacA molecule. R-LPS was bound specifically to MacA protein with affinity exceeding that of polymyxin B. Sequence analyses showed that MacA contains two high-density clusters of positively charged amino acid residues located in the cytoplasmic N-terminal domain and the periplasmic C-terminal domain. Substitutions in the C-terminal cluster reducing the positive-charge density completely abolished binding of R-LPS. At the same time, these substitutions significantly reduced the functionality of MacA in the protection of E. coli against macrolides in vivo and in the in vitro MacB ATPase stimulation assays. Taken together, our results suggest that R-LPS or a similar glycolipid is a physiological substrate of MacAB-TolC. PMID:23974027

The effect of nitrous oxide on the minimum alveolar concentration (MAC) and MAC derivatives of isoflurane in dogs

PubMed Central

Voulgaris, Debra A.; Egger, Christine M.; Seddighi, M. Reza; Rohrbach, Barton W.; Love, Lydia C.; Doherty, Thomas J.

2013-01-01

This study investigated the effects of 70% nitrous oxide (N2O) on the minimum alveolar concentration (MAC) of isoflurane (ISO) that prevents purposeful movement, the MAC of ISO at which there is no motor movement (MACNM), and the MAC of ISO at which autonomic responses are blocked (MACBAR) in dogs. Six adult, healthy, mixed-breed, intact male dogs were anesthetized with ISO delivered via mask. Baseline MAC, MACNM, and MACBAR of ISO were determined for each dog using a supra-maximal electrical stimulus (50 V, 50 Hz, 10 ms). Nitrous oxide (70%) was then administered and MAC and its derivatives (N2O-MAC, N2O-MACNM, and N2O-MACBAR) were determined using the same methodology. The values for baseline MAC, MACNM, and MACBAR were 1.39 ± 0.14, 1.59 ± 0.10, and 1.72 ± 0.16, respectively. The addition of 70% N2O decreased MAC, MACNM, and MACBAR by 32%, 15%, and 25%, respectively. PMID:24082405

Development, cognition, and behaviour in Pitt-Hopkins syndrome.

PubMed

Van Balkom, Ingrid D C; Vuijk, Pieter Jelle; Franssens, Marijke; Hoek, Hans W; Hennekam, Raoul C M

2012-10-01

The aim of the study was to collect detailed data on behavioural, adaptive, and psychological functioning in 10 individuals with Pitt-Hopkins syndrome (PTHS), with specific attention to manifestations of autism spectrum disorder (ASD). The participants (four females, six males), residing in the Netherlands and Belgium, were ascertained through the Dutch national PTHS support group. Median age of participants was 10 years, the age range was between 32 and 289 months. They underwent psychiatric examinations and neuropsychological measurements using a comprehensive assessment battery. Additionally, parental information was gathered through standardized interviews and questionnaires. Findings were compared with those from the literature. All participants showed profound intellectual disability, amiable demeanour with minimal maladaptive behaviours, severe impairments of communication and language, and intense, frequent motor stereotypies. Impairments in all participants were beyond what would be expected for cognitive abilities, fitting a classification of ASD. Patients with PTHS are characterized not only by specific physical and genetic manifestations but also by specific behavioural and cognitive characteristics. Studying behaviour and cognition may improve diagnosis and prognosis, allows recognition of comorbidities, and contributes to adequate counselling of families. © The Authors. Developmental Medicine & Child Neurology © 2012 Mac Keith Press.

On Searching Available Channels with Asynchronous MAC-Layer Spectrum Sensing

NASA Astrophysics Data System (ADS)

Jiang, Chunxiao; Ma, Xin; Chen, Canfeng; Ma, Jian; Ren, Yong

Dynamic spectrum access has become a focal issue recently, in which identifying the available spectrum plays a rather important role. Lots of work has been done concerning secondary user (SU) synchronously accessing primary user's (PU's) network. However, on one hand, SU may have no idea about PU's communication protocols; on the other, it is possible that communications among PU are not based on synchronous scheme at all. In order to address such problems, this paper advances a strategy for SU to search available spectrums with asynchronous MAC-layer sensing. With this method, SUs need not know the communication mechanisms in PU's network when dynamically accessing. We will focus on four aspects: 1) strategy for searching available channels; 2) vacating strategy when PUs come back; 3) estimation of channel parameters; 4) impact of SUs' interference on PU's data rate. The simulations show that our search strategy not only can achieve nearly 50% less interference probability than equal allocation of total search time, but also well adapts to time-varying channels. Moreover, access by our strategies can attain 150% more access time than random access. The moment matching estimator shows good performance in estimating and tracing time-varying channels.

Constraints of nonresponding flows based on cross layers in the networks

NASA Astrophysics Data System (ADS)

Zhou, Zhi-Chao; Xiao, Yang; Wang, Dong

2016-02-01

In the active queue management (AQM) scheme, core routers cannot manage and constrain user datagram protocol (UDP) data flows by the sliding window control mechanism in the transport layer due to the nonresponsive nature of such traffic flows. However, the UDP traffics occupy a large part of the network service nowadays which brings a great challenge to the stability of the more and more complex networks. To solve the uncontrollable problem, this paper proposes a cross layers random early detection (CLRED) scheme, which can control the nonresponding UDP-like flows rate effectively when congestion occurs in the access point (AP). The CLRED makes use of the MAC frame acknowledgement (ACK) transmitting congestion information to the sources nodes and utilizes the back-off windows of the MAC layer throttling data rate. Consequently, the UDP-like flows data rate can be restrained timely by the sources nodes in order to alleviate congestion in the complex networks. The proposed CLRED can constrain the nonresponsive flows availably and make the communication expedite, so that the network can sustain stable. The simulation results of network simulator-2 (NS2) verify the proposed CLRED scheme.

Oligomeric Bax Is a Component of the Putative Cytochrome c Release Channel MAC, Mitochondrial Apoptosis-induced Channel

PubMed Central

Dejean, Laurent M.; Martinez-Caballero, Sonia; Guo, Liang; Hughes, Cynthia; Teijido, Oscar; Ducret, Thomas; Ichas, François; Korsmeyer, Stanley J.; Antonsson, Bruno; Jonas, Elizabeth A.; Kinnally, Kathleen W.

2005-01-01

Bcl-2 family proteins regulate apoptosis, in part, by controlling formation of the mitochondrial apoptosis-induced channel (MAC), which is a putative cytochrome c release channel induced early in the intrinsic apoptotic pathway. This channel activity was never observed in Bcl-2–overexpressing cells. Furthermore, MAC appears when Bax translocates to mitochondria and cytochrome c is released in cells dying by intrinsic apoptosis. Bax is a component of MAC of staurosporine-treated HeLa cells because MAC activity is immunodepleted by Bax antibodies. MAC is preferentially associated with oligomeric, not monomeric, Bax. The single channel behavior of recombinant oligomeric Bax and MAC is similar. Both channel activities are modified by cytochrome c, consistent with entrance of this protein into the pore. The mean conductance of patches of mitochondria isolated after green fluorescent protein-Bax translocation is significantly higher than those from untreated cells, consistent with onset of MAC activity. In contrast, the mean conductance of patches of mitochondria indicates MAC activity is present in apoptotic cells deficient in Bax but absent in apoptotic cells deficient in both Bax and Bak. These findings indicate Bax is a component of MAC in staurosporine-treated HeLa cells and suggest Bax and Bak are functionally redundant as components of MAC. PMID:15772159

The benefits of a comprehensive rehabilitation program in patients diagnosed with spastic quadriplegia

PubMed Central

Rogoveanu, OC; Tuțescu, NC; Kamal, D; Alexandru, DO; Kamal, C; Streba, CT; Trăistaru, MR

2016-01-01

Spastic quadriplegia has as an etiopathogenic substrate, a non-progressive brain lesion; however, the clinical manifestations of the disease evolve over time. Children diagnosed with spastic quadriplegia show a variety of symptoms in different areas: sensorimotor, emotional, cognitive, and social. The purpose of this study was to assess the functional status in patients diagnosed with spastic quadriplegia, who followed a complex medical rehabilitation program, during a year, and highlight the importance of using physical and kinetic techniques in improving their status. A total of 10 children diagnosed with spastic quadriplegia were included in the study and the Gross Motor Function Classification System (GMFCS) and manual ability classification system (MACS) were used to evaluate the functionality status of each patient. Every patient was evaluated initially (T1), after six months of program (T2), and after they completed the study. All the children were originally monitored daily, for 5 days per week for a period of one month, then two times a week for a year. A statistically significant difference regarding the modification of the GMFCS and MACS stage was found, which occurred between the first and the third evaluation. The inverse correlation of the statistical significance between the ages of patients and the decrease in GMFCS or MACS stage was highlighted; the younger the patient, the more the scale decreased. A direct link between the gross motor function and the manual ability was noticed. Applying a complex rehabilitation program has proven efficient by improving both the gross motor functionality and the manual ability. PMID:27974931

The benefits of a comprehensive rehabilitation program in patients diagnosed with spastic quadriplegia.

PubMed

Rogoveanu, O C; Tuțescu, N C; Kamal, D; Alexandru, D O; Kamal, C; Streba, C T; Trăistaru, M R

2016-01-01

Spastic quadriplegia has as an etiopathogenic substrate, a non-progressive brain lesion; however, the clinical manifestations of the disease evolve over time. Children diagnosed with spastic quadriplegia show a variety of symptoms in different areas: sensorimotor, emotional, cognitive, and social. The purpose of this study was to assess the functional status in patients diagnosed with spastic quadriplegia, who followed a complex medical rehabilitation program, during a year, and highlight the importance of using physical and kinetic techniques in improving their status. A total of 10 children diagnosed with spastic quadriplegia were included in the study and the Gross Motor Function Classification System (GMFCS) and manual ability classification system (MACS) were used to evaluate the functionality status of each patient. Every patient was evaluated initially (T1), after six months of program (T2), and after they completed the study. All the children were originally monitored daily, for 5 days per week for a period of one month, then two times a week for a year. A statistically significant difference regarding the modification of the GMFCS and MACS stage was found, which occurred between the first and the third evaluation. The inverse correlation of the statistical significance between the ages of patients and the decrease in GMFCS or MACS stage was highlighted; the younger the patient, the more the scale decreased. A direct link between the gross motor function and the manual ability was noticed. Applying a complex rehabilitation program has proven efficient by improving both the gross motor functionality and the manual ability.

Competence of depressed patients for consent to research.

PubMed

Appelbaum, P S; Grisso, T; Frank, E; O'Donnell, S; Kupfer, D J

1999-09-01

The capacities of depressed patients to consent to research have been questioned by commentators who fear that the cognitive effects of a disorder may impair subjects' abilities to protect their interests. This study used a new instrument for assessing depressed patients' capacities to consent to research and examined their performance, including the relation between severity of depression and extent of impairment. Twenty-six female outpatients with major depression (assessed with the Schedule of Affective Disorders and Schizophrenia-Lifetime Version) enrolled in a study of maintenance psychotherapy were recruited for this project. Consent-related abilities were measured with the MacArthur Competence Assessment Tool-Clinical Research (MacCAT-CR) 1 week after intake and again 8-10 weeks later. Depressive symptoms were measured by the Hamilton Depression Rating Scale. Almost all subjects performed quite well on the capacity measures and maintained that level of performance over time. There was no correlation between performance and degree of depressive symptoms and little relation to prior research experience. Some subjects appeared confused about the extent to which decisions about assignment to treatment groups would be made on the basis of their clinical condition rather than randomly. This outpatient group with major depression showed few impairments in their decision-making capacities related to research. As in other studies, some concerns were raised about subjects' appreciation that treatment assignments would not be individualized for their needs. Examination of hospitalized patients and those with psychotic depression would help to determine whether they show greater degrees of impairment. The MacCAT-CR was easily adapted for use with this depressed group.

Introduction to MAC CRM training

NASA Technical Reports Server (NTRS)

Brown, Donald D.

1987-01-01

The author introduces the Military Airlift Command (MAC) and its mission. A brief history of Cockpit Resource Management (CRM) as it relates to MAC is given. He also states why MAC is currently interested in CRM.

Methamphetamine-Associated Cardiomyopathy

PubMed Central

Won, Sekon; Hong, Robert A.; Shohet, Ralph V.; Seto, Todd B.; Parikh, Nisha I.

2015-01-01

Methamphetamine and related compounds are now the second most commonly used illicit substance worldwide, after cannabis. Reports of methamphetamine-associated cardiomyopathy (MAC) are increasing, but MAC has not been well reviewed. This analysis of MAC will provide an overview of the pharmacology of methamphetamine, historical perspective and epidemiology, a review of case and clinical studies, and a summary of the proposed mechanisms for MAC. Clinically, many questions remain, including the appropriate therapeutic interventions for MAC, the incidence and prevalence of cardiac pathology in methamphetamine users, risk factors for developing MAC, and prognosis of these patients. In conclusion, recognition of the significance of MAC among physicians and other medical caregivers is important given the growing use of methamphetamine and related stimulants worldwide. PMID:24037954

Effect of episodic and working memory impairments on semantic and cognitive procedural learning at alcohol treatment entry.

PubMed

Pitel, Anne Lise; Witkowski, Thomas; Vabret, François; Guillery-Girard, Bérengère; Desgranges, Béatrice; Eustache, Francis; Beaunieux, Hélène

2007-02-01

Chronic alcoholism is known to impair the functioning of episodic and working memory, which may consequently reduce the ability to learn complex novel information. Nevertheless, semantic and cognitive procedural learning have not been properly explored at alcohol treatment entry, despite its potential clinical relevance. The goal of the present study was therefore to determine whether alcoholic patients, immediately after the weaning phase, are cognitively able to acquire complex new knowledge, given their episodic and working memory deficits. Twenty alcoholic inpatients with episodic memory and working memory deficits at alcohol treatment entry and a control group of 20 healthy subjects underwent a protocol of semantic acquisition and cognitive procedural learning. The semantic learning task consisted of the acquisition of 10 novel concepts, while subjects were administered the Tower of Toronto task to measure cognitive procedural learning. Analyses showed that although alcoholic subjects were able to acquire the category and features of the semantic concepts, albeit slowly, they presented impaired label learning. In the control group, executive functions and episodic memory predicted semantic learning in the first and second halves of the protocol, respectively. In addition to the cognitive processes involved in the learning strategies invoked by controls, alcoholic subjects seem to attempt to compensate for their impaired cognitive functions, invoking capacities of short-term passive storage. Regarding cognitive procedural learning, although the patients eventually achieved the same results as the controls, they failed to automate the procedure. Contrary to the control group, the alcoholic groups' learning performance was predicted by controlled cognitive functions throughout the protocol. At alcohol treatment entry, alcoholic patients with neuropsychological deficits have difficulty acquiring novel semantic and cognitive procedural knowledge. Compared with controls, they seem to use more costly learning strategies, which are nonetheless less efficient. These learning disabilities need to be considered when treatment requiring the acquisition of complex novel information is envisaged.

Identification of Human Cathelicidin Peptide LL-37 as a Ligand for Macrophage Integrin αMβ2 (Mac-1, CD11b/CD18) that Promotes Phagocytosis by Opsonizing Bacteria

PubMed Central

Lishko, Valeryi K.; Moreno, Benjamin; Podolnikova, Nataly P.; Ugarova, Tatiana P.

2016-01-01

LL-37, a cationic antimicrobial peptide, has numerous immune-modulating effects. However, the identity of a receptor(s) mediating the responses in immune cells remains uncertain. We have recently demonstrated that LL-37 interacts with the αMI-domain of integrin αMβ2 (Mac-1), a major receptor on the surface of myeloid cells, and induces a migratory response in Mac-1-expressing monocyte/macrophages as well as activation of Mac-1 on neutrophils. Here, we show that LL-37 and its C-terminal derivative supported strong adhesion of various Mac-1-expressing cells, including HEK293 cells stably transfected with Mac-1, human U937 monocytic cells and murine IC-21 macrophages. The cell adhesion to LL-37 was partially inhibited by specific Mac-1 antagonists, including mAb against the αM integrin subunit and neutrophil inhibitory factor, and completely blocked when anti-Mac-1 antibodies were combined with heparin, suggesting that cell surface heparan sulfate proteoglycans act cooperatively with integrin Mac-1. Coating both Gram-negative and Gram-positive bacteria with LL-37 significantly potentiated their phagocytosis by macrophages, and this process was blocked by a combination of anti-Mac-1 mAb and heparin. Furthermore, phagocytosis by wild-type murine peritoneal macrophages of LL-37-coated latex beads, a model of foreign surfaces, was several fold higher than that of untreated beads. By contrast, LL-37 failed to augment phagocytosis of beads by Mac-1-deficient macrophages. These results identify LL-37 as a novel ligand for integrin Mac-1 and demonstrate that the interaction between Mac-1 on macrophages and bacteria-bound LL-37 promotes phagocytosis. PMID:27990411

Minimum alveolar concentration (MAC) for sevoflurane and xenon at normothermia and hypothermia in newborn pigs.

PubMed

Liu, X; Dingley, J; Elstad, M; Scull-Brown, E; Steen, P A; Thoresen, M

2013-05-01

Neuroprotection from therapeutic hypothermia increases when combined with the anaesthetic gas xenon in animal studies. A clinical feasibility study of the combined treatment has been successfully undertaken in asphyxiated human term newborns. It is unknown whether xenon alone would be sufficient for sedation during hypothermia eliminating or reducing the need for other sedative or analgesic infusions in ventilated sick infants. Minimum alveolar concentration (MAC) of xenon is unknown in any neonatal species. Eight newborn pigs were anaesthetised with sevoflurane alone and then sevoflurane plus xenon at two temperatures. Pigs were randomised to start at either 38.5°C or 33.5°C. MAC for sevoflurane was determined using the claw clamp technique at the preset body temperature. For xenon MAC determination, a background of 0.5 MAC sevoflurane was used, and 60% xenon added to the gas mixture. The relationship between sevoflurane and xenon MAC is assumed to be additive. Xenon concentrations were changed in 5% steps until a positive clamp reaction was noted. Pigs' temperature was changed to the second target, and two MAC determinations for sevoflurane and 0.5 MAC sevoflurane plus xenon were repeated. MAC for sevoflurane was 4.1% [95% confidence interval (CI): 3.65-4.50] at 38.5°C and 3.05% (CI: 2.63-3.48) at 33.5°C, a significant reduction. MAC for xenon was 120% at 38.5°C and 116% at 33.5°C, not different. In newborn swine sevoflurane, MAC was temperature dependent, while xenon MAC was independent of temperature. There was large individual variability in xenon MAC, from 60% to 120%. © 2013 The Acta Anaesthesiologica Scandinavica Foundation.

Components of Effective Cognitive-Behavioral Therapy for Pediatric Headache: A Mixed Methods Approach

PubMed Central

Law, Emily F.; Beals-Erickson, Sarah E.; Fisher, Emma; Lang, Emily A.; Palermo, Tonya M.

2017-01-01

Internet-delivered treatment has the potential to expand access to evidence-based cognitive-behavioral therapy (CBT) for pediatric headache, and has demonstrated efficacy in small trials for some youth with headache. We used a mixed methods approach to identify effective components of CBT for this population. In Study 1, component profile analysis identified common interventions delivered in published RCTs of effective CBT protocols for pediatric headache delivered face-to-face or via the Internet. We identified a core set of three treatment components that were common across face-to-face and Internet protocols: 1) headache education, 2) relaxation training, and 3) cognitive interventions. Biofeedback was identified as an additional core treatment component delivered in face-to-face protocols only. In Study 2, we conducted qualitative interviews to describe the perspectives of youth with headache and their parents on successful components of an Internet CBT intervention. Eleven themes emerged from the qualitative data analysis, which broadly focused on patient experiences using the treatment components and suggestions for new treatment components. In the Discussion, these mixed methods findings are integrated to inform the adaptation of an Internet CBT protocol for youth with headache. PMID:29503787

Components of Effective Cognitive-Behavioral Therapy for Pediatric Headache: A Mixed Methods Approach.

PubMed

Law, Emily F; Beals-Erickson, Sarah E; Fisher, Emma; Lang, Emily A; Palermo, Tonya M

2017-01-01

Internet-delivered treatment has the potential to expand access to evidence-based cognitive-behavioral therapy (CBT) for pediatric headache, and has demonstrated efficacy in small trials for some youth with headache. We used a mixed methods approach to identify effective components of CBT for this population. In Study 1, component profile analysis identified common interventions delivered in published RCTs of effective CBT protocols for pediatric headache delivered face-to-face or via the Internet. We identified a core set of three treatment components that were common across face-to-face and Internet protocols: 1) headache education, 2) relaxation training, and 3) cognitive interventions. Biofeedback was identified as an additional core treatment component delivered in face-to-face protocols only. In Study 2, we conducted qualitative interviews to describe the perspectives of youth with headache and their parents on successful components of an Internet CBT intervention. Eleven themes emerged from the qualitative data analysis, which broadly focused on patient experiences using the treatment components and suggestions for new treatment components. In the Discussion, these mixed methods findings are integrated to inform the adaptation of an Internet CBT protocol for youth with headache.

The Role of the Transcription Factors MtrR and MtrA in the Fitness of the Pathogen Neisseria gonorrhoeae

DTIC Science & Technology

2007-10-19

MacA -MacB efflux pump is expressed at very low levels in N. gonorrhoeae; however, experimental alteration of the promoter sequence showed that the...specificity (132). The gonococcus expresses four efflux pump systems, namely MtrC-Mtr-D-MtrE (64), FarA-FarB-MtrE (97), NorM (158), and MacA -MacB (161...2005. Characterization of the MacA -MacB efflux system in Neisseria gonorrhoeae. The Journal of antimicrobial chemotherapy 56:856-860. 162. Rouquette, C

Mac-1 (CD11b/CD18) is essential for Fc receptor-mediated neutrophil cytotoxicity and immunologic synapse formation.

PubMed

van Spriel, A B; Leusen, J H; van Egmond, M; Dijkman, H B; Assmann, K J; Mayadas, T N; van de Winkel, J G

2001-04-15

Receptors for human immunoglobulin (Ig)G and IgA initiate potent cytolysis of antibody (Ab)-coated targets by polymorphonuclear leukocytes (PMNs). Mac-1 (complement receptor type 3, CD11b/CD18) has previously been implicated in receptor cooperation with Fc receptors (FcRs). The role of Mac-1 in FcR-mediated lysis of tumor cells was characterized by studying normal human PMNs, Mac-1-deficient mouse PMNs, and mouse PMNs transgenic for human FcR. All PMNs efficiently phagocytosed Ab-coated particles. However, antibody-dependent cellular cytotoxicity (ADCC) was abrogated in Mac-1(-/-) PMNs and in human PMNs blocked with anti-Mac-1 monoclonal Ab (mAb). Mac-1(-/-) PMNs were unable to spread on Ab-opsonized target cells and other Ab-coated surfaces. Confocal laser scanning and electron microscopy revealed a striking difference in immunologic synapse formation between Mac-1(-/-) and wild-type PMNs. Also, respiratory burst activity could be measured outside membrane-enclosed compartments by using Mac-1(-/-) PMNs bound to Ab-coated tumor cells, in contrast to wild-type PMNs. In summary, these data document an absolute requirement of Mac-1 for FcR-mediated PMN cytotoxicity toward tumor targets. Mac-1(-/-) PMNs exhibit defective spreading on Ab-coated targets, impaired formation of immunologic synapses, and absent tumor cytolysis.

Conversion of the Aeronautics Interactive Workstation

NASA Technical Reports Server (NTRS)

Riveras, Nykkita L.

2004-01-01

This summer I am working in the Educational Programs Office. My task is to convert the Aeronautics Interactive Workstation from a Macintosh (Mac) platform to a Personal Computer (PC) platform. The Aeronautics Interactive Workstation is a workstation in the Aerospace Educational Laboratory (AEL), which is one of the three components of the Science, Engineering, Mathematics, and Aerospace Academy (SEMAA). The AEL is a state-of-the-art, electronically enhanced, computerized classroom that puts cutting-edge technology at the fingertips of participating students. It provides a unique learning experience regarding aerospace technology that features activities equipped with aerospace hardware and software that model real-world challenges. The Aeronautics Interactive Workstation, in particular, offers a variety of activities pertaining to the history of aeronautics. When the Aeronautics Interactive Workstation was first implemented into the AEL it was designed with Macromedia Director 4 for a Mac. Today it is being converted to Macromedia DirectorMX2004 for a PC. Macromedia Director is the proven multimedia tool for building rich content and applications for CDs, DVDs, kiosks, and the Internet. It handles the widest variety of media and offers powerful features for building rich content that delivers red results, integrating interactive audio, video, bitmaps, vectors, text, fonts, and more. Macromedia Director currently offers two programmingkripting languages: Lingo, which is Director's own programmingkripting language and JavaScript. In the workstation, Lingo is used in the programming/scripting since it was the only language in use when the workstation was created. Since the workstation was created with an older version of Macromedia Director it hosted significantly different programming/scripting protocols. In order to successfully accomplish my task, the final product required correction of Xtra and programming/scripting errors. I also had to convert the Mac platform file extensions into compatible file extensions for a PC.

Analysing efficiency of IPv6 packet transmission over 6LoWPAN network

NASA Astrophysics Data System (ADS)

Kozłowski, Adam; Sosnowski, Janusz

2017-08-01

Practical proliferation of Internet of Things (IoT) concept depends upon communication efficiency in the related network. In the paper we outline basic features of wireless communication protocols used in IoT and concentrate on analysing communication overheads. In particular, we discuss the impact of IPv6 packet length on 6LoWPAN network operation with physical and MAC layer defined by IEEE 802.15.4 standard. The presented analysis methodology is useful in estimation of the total goodput (throughput at the application level) and energy consumptions within the whole traffic model which are the crucial features of IoT networks.

Dengue hemorrhagic fever and acute hepatitis: a case report.

PubMed

Mourão, Maria Paula Gomes; Lacerda, Marcus Vinícius Guimarães de; Bastos, Michele de Souza; Albuquerque, Bernardino Cláudio de; Alecrim, Wilson Duarte

2004-12-01

Dengue fever is the world's most important viral hemorrhagic fever disease, the most geographically wide-spread of the arthropod-born viruses, and it causes a wide clinical spectrum of disease. We report a case of dengue hemorrhagic fever complicated by acute hepatitis. The initial picture of classical dengue fever was followed by painful liver enlargement, vomiting, hematemesis, epistaxis and diarrhea. Severe liver injury was detected by laboratory investigation, according to a syndromic surveillance protocol, expressed in a self-limiting pattern and the patient had a complete recovery. The serological tests for hepatitis and yellow fever viruses were negative. MAC-ELISA for dengue was positive.

Resource allocation for multichannel broadcasting visible light communication

NASA Astrophysics Data System (ADS)

Le, Nam-Tuan; Jang, Yeong Min

2015-11-01

Visible light communication (VLC), which offers the possibility of using light sources for both illumination and data communications simultaneously, will be a promising incorporation technique with lighting applications. However, it still remains some challenges especially coverage because of field-of-view limitation. In this paper, we focus on this issue by suggesting a resource allocation scheme for VLC broadcasting system. By using frame synchronization and a network calculus QoS approximation, as well as diversity technology, the proposed VLC architecture and QoS resource allocation for the multichannel-broadcasting MAC (medium access control) protocol can solve the coverage limitation problem and the link switching problem of exhibition service.

Photocopy of drawing (original drawing of MacDill Field in possession ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Photocopy of drawing (original drawing of MacDill Field in possession of MacDill Air Force Base, Civil Engineering, Tampa, Florida; 1952 architectural drawings by Strategic Air Command, MacDill Air Force Base) BASE LAYOUT, 1952 - MacDill Air Force Base, Bounded by City of Tampa North, Tampa Bay South, Old Tampa Bay West, & Hillsborough Bay East, Tampa, Hillsborough County, FL

Protocol for Short- and Longer-term Spatial Learning and Memory in Mice

PubMed Central

Willis, Emily F.; Bartlett, Perry F.; Vukovic, Jana

2017-01-01

Studies on the role of the hippocampus in higher cognitive functions such as spatial learning and memory in rodents are reliant upon robust and objective behavioral tests. This protocol describes one such test—the active place avoidance (APA) task. This behavioral task involves the mouse continuously integrating visual cues to orientate itself within a rotating arena in order to actively avoid a shock zone, the location of which remains constant relative to the room. This protocol details the step-by-step procedures for a novel paradigm of the hippocampal-dependent APA task, measuring acquisition of spatial learning during a single 20-min trial (i.e., short-term memory), with spatial memory encoding and retrieval (i.e., long-term memory) assessed by trials conducted over consecutive days. Using the APA task, cognitive flexibility can be assessed using the reversal learning paradigm, as this increases the cognitive load required for efficient performance in the task. In addition to a detailed experimental protocol, this paper also describes the range of its possible applications, the expected key results, as well as the analytical methods to assess the data, and the pitfalls/troubleshooting measures. The protocol described herein is highly robust and produces replicable results, thus presenting an important paradigm that enables the assessment of subtle short-term changes in spatial learning and memory, such as those observed for many experimental interventions. PMID:29089878

Mitral annular calcification in patients undergoing aortic valve replacement for aortic valve stenosis.

PubMed

Takami, Yoshiyuki; Tajima, Kazuyoshi

2016-02-01

Limited data exis t on clinical relevance of aortic valve stenosis (AVS) and mitral annular calcification (MAC), although with similar pathophysiologic basis. We sought to reveal the prevalence of MAC and its clinical features in the patients undergoing aortic valve replacement (AVR) for AVS. We reviewed 106 consecutive patients who underwent isolated AVR from 2004 to 2010. Before AVR, CT scans were performed to identify MAC, whose severity was graded on a scale of 0-4, with grade 0 denoting no MAC and grade 4 indicating severe MAC. Echocardiography was performed before AVR and at follow-up over 2 years after AVR. MAC was identified in 56 patients with grade 1 (30 %), 2 (39 %), 3 (18 %), and 4 (13 %), respectively. Patients with MAC presented older age (72 ± 8 versus 66 ± 11 years), higher rate of dialysis-dependent renal failure (43 versus 4 %), and less frequency of bicuspid aortic valve (9 versus 36 %), when compared to those without MAC. No significant differences were seen in short- and mid-term mortality after AVR between the groups. In patients with MAC, progression of neither mitral regurgitation nor stenosis was observed at follow-up of 53 ± 23 months for 102 survivors, although the transmitral flow velocities were higher than in those without MAC. In conclusion, MAC represented 53 % of the patients undergoing isolated AVR for AVS, usually appeared in dialysis-dependent elder patients with tricuspid AVS. MAC does not affect adversely upon the survival, without progression of mitral valve disease, at least within 2 years after AVR.

Prediction of post-stroke dementia using NINDS-CSN 5-minute neuropsychology protocol in acute stroke.

PubMed

Lim, Jae-Sung; Oh, Mi Sun; Lee, Ju-Hun; Jung, San; Kim, Chulho; Jang, Min Uk; Lee, Sang-Hwa; Kim, Yeo Jin; Kim, Yerim; Park, Jaeseol; Kang, Yeonwook; Yu, Kyung-Ho; Lee, Byung-Chul

2017-05-01

The National Institute of Neurological Disease and Stroke-Canadian Stroke Network (NINDS-CSN) 5-minute neuropsychology protocol consists of only verbal tasks, and is proposed as a brief screening method for vascular cognitive impairment. We evaluated its feasibility within two weeks after stroke and ability to predict the development of post-stroke dementia (PSD) at 3 months after stroke. We prospectively enrolled subjects with ischemic stroke within seven days of symptom onset who were consecutively admitted to 12 university hospitals. Neuropsychological assessments using the NINDS-CSN 5-minute and 60-minute neuropsychology protocols were administered within two weeks and at 3 months after stroke onset, respectively. PSD was diagnosed with reference to the American Heart Association/American Stroke Association statement, requiring deficits in at least two cognitive domains. Of 620 patients, 512 (82.6%) were feasible for the NINDS-CSN 5-minute protocol within two weeks after stroke. The incidence of PSD was 16.2% in 308 subjects who had completed follow-up at 3 months after stroke onset. The total score of the NINDS-CSN 5-minute protocol differed significantly between those with and without PSD (4.0 ± 2.7, 7.4 ± 2.7, respectively; p < 0.01). A cut-off value of 6/7 showed reasonable discriminative power (sensitivity 0.82, specificity 0.67, AUC 0.74). The NINDS-CSN 5-minute protocol score was a significant predictor for PSD (adjusted odds ratio 6.32, 95% CI 2.65-15.05). The NINDS-CSN 5-minute protocol is feasible to evaluate cognitive functions in patients with acute ischemic stroke. It might be a useful screening method for early identification of high-risk groups for PSD.

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

Fu Guo; Institute of Neuroscience, Department of Neurobiology, Second Military Medical University, Shanghai 200433; Yang Huayan

Macrophage differentiation antigen associated with complement three receptor function (Mac-1) belongs to {beta}{sub 2} subfamily of integrins that mediate important cell-cell and cell-extracellular matrix interactions. Biochemical studies have indicated that Mac-1 is a constitutive heterodimer in vitro. Here, we detected the heterodimerization of Mac-1 subunits in living cells by means of two fluorescence resonance energy transfer (FRET) techniques (fluorescence microscopy and fluorescence spectroscopy) and our results demonstrated that there is constitutive heterodimerization of the Mac-1 subunits and this constitutive heterodimerization of the Mac-1 subunits is cell-type independent. Through FRET imaging, we found that heterodimers of Mac-1 mainly localized in plasmamore » membrane, perinuclear, and Golgi area in living cells. Furthermore, through analysis of the estimated physical distances between cyan fluorescent protein (CFP) and yellow fluorescent protein (YFP) fused to Mac-1 subunits, we suggested that the conformation of Mac-1 subunits is not affected by the fusion of CFP or YFP and inferred that Mac-1 subunits take different conformation when expressed in Chinese hamster ovary (CHO) and human embryonic kidney (HEK) 293T cells, respectively.« less

New secure communication-layer standard for medical image management (ISCL)

NASA Astrophysics Data System (ADS)

Kita, Kouichi; Nohara, Takashi; Hosoba, Minoru; Yachida, Masuyoshi; Yamaguchi, Masahiro; Ohyama, Nagaaki

1999-07-01

This paper introduces a summary of the standard draft of ISCL 1.00 which will be published by MEDIS-DC officially. ISCL is abbreviation of Integrated Secure Communication Layer Protocols for Secure Medical Image Management Systems. ISCL is a security layer which manages security function between presentation layer and TCP/IP layer. ISCL mechanism depends on basic function of a smart IC card and symmetric secret key mechanism. A symmetry key for each session is made by internal authentication function of a smart IC card with a random number. ISCL has three functions which assure authentication, confidently and integrity. Entity authentication process is done through 3 path 4 way method using functions of internal authentication and external authentication of a smart iC card. Confidentially algorithm and MAC algorithm for integrity are able to be selected. ISCL protocols are communicating through Message Block which consists of Message Header and Message Data. ISCL protocols are evaluating by applying to regional collaboration system for image diagnosis, and On-line Secure Electronic Storage system for medical images. These projects are supported by Medical Information System Development Center. These project shows ISCL is useful to keep security.

Research on a Banknote Printing Wastewater Monitoring System based on Wireless Sensor Network

NASA Astrophysics Data System (ADS)

Li, B. B.; Yuan, Z. F.

2006-10-01

In this paper, a banknote printing wastewater monitoring system based on WSN is presented in line with the system demands and actual condition of the worksite for a banknote printing factory. In Physical Layer, the network node is a nRF9e5-centric embedded instrument, which can realize the multi-function such as data collecting, status monitoring, wireless data transmission and so on. Limited by the computing capability, memory capability, communicating energy and others factors, it is impossible for the node to get every detail information of the network, so the communication protocol on WSN couldn't be very complicated. The competitive-based MACA (Multiple Access with Collision Avoidance) Protocol is introduced in MAC, which can decide the communication process and working mode of the nodes, avoid the collision of data transmission, hidden and exposed station problem of nodes. On networks layer, the routing protocol in charge of the transmitting path of the data, the networks topology structure is arranged based on address assignation. Accompanied with some redundant nodes, the network performances stabile and expandable. The wastewater monitoring system is a tentative practice of WSN theory in engineering. Now, the system has passed test and proved efficiently.

The Use of Cognitive Task Analysis and Simulators for After Action Review of Medical Events in Iraq

DTIC Science & Technology

2006-12-01

research attempts to improve medical AAR with a novel combination of Cognitive Task Analysis conducted while interviewees moulage simulators (Clark and...hypothesized that our protocol which employed a novel combination of medical Cognitive Task Analysis combined with the moulage of instruments and depictions

Association of physical activity with cognition, metacognition and academic performance in children and adolescents: a protocol for systematic review and meta-analysis.

PubMed

Álvarez-Bueno, Celia; Pesce, Caterina; Cavero-Redondo, Iván; Sánchez-López, Mairena; Pardo-Guijarro, María Jesús; Martínez-Vizcaíno, Vicente

2016-06-28

Schools provide a relevant context for improving children's and adolescents' physical and mental health by increasing physical activity during school hours and/or beyond. The interest in the relationship between physical activity programmes and cognition during development has recently increased, with evidence suggesting a positive association. We present a protocol of systematic reviews and meta-analysis of intervention studies that, by determining the effects of chronic physical exercise on children's and adolescents' cognitive and metacognitive functions, cognitive life skills, academic behaviours and achievement, aims to ensure procedural objectivity and transparency, and maximise the extraction of relevant information to inform policy development. This protocol is guided by Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) and by the Cochrane Collaboration Handbook. Databases to be utilised for a thorough selection of the pertinent literature are MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, Web of Science, PsycINFO and ERIC. Selection is proposed to encompass an international and a national publication level, with inclusion of experimental studies written in English or in Spanish, respectively. Also, relevant references included in the selected studies will be considered suitable for review as supplemental sources.We present an integrated approach to the methodological quality assessment of the selected studies, including the Jadad Scale for the assessment of the quality of randomised controlled trials and the Quality Assessment Tool for Quantitative Studies for pre-post studies and non-randomised controlled trials. The pre-post interventions mean differences will be the primary indicator of the intervention outcome. A subgroup analysis is proposed based on cognitive functions and their neural correlates, metacognitive functions and cognitive life skills, academic achievement areas and academic behaviours. PROSPERO CRD42015029913. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Translating patient reported outcome measures: methodological issues explored using cognitive interviewing with three rheumatoid arthritis measures in six European languages.

PubMed

Hewlett, Sarah; Nicklin, Joanna; Bode, Chistina; Carmona, Loreto; Dures, Emma; Engelbrecht, Matthias; Hagel, Sofia; Kirwan, John; Molto, Anna; Redondo, Marta; Gossec, Laure

2016-06-01

Cross-cultural translation of patient-reported outcome measures (PROMs) is a lengthy process, often performed professionally. Cognitive interviewing assesses patient comprehension of PROMs. The objective was to evaluate the usefulness of cognitive interviewing to assess translations and compare professional (full) with non-professional (simplified) translation processes. A full protocol used for the Bristol RA Fatigue Multi-dimensional Questionnaire and Numerical Rating Scale (BRAF-MDQ, BRAF-NRS) was compared with a simplified protocol used for the RA Impact of Disease scale (RAID). RA patients in the UK, France, the Netherlands, Germany, Spain and Sweden completed the PROMs during cognitive interviewing (BRAFs in the UK were omitted as these were performed during development). Transcripts were deductively analysed for understanding, information retrieval, judgement and response options. Usefulness of cognitive interviewing was assessed by the nature of problems identified, and translation processes by percentage of consistently problematic items (⩾40% patients per country with similar concerns). Sixty patients participated (72% women). For the BRAFs (full protocol) one problematic item was identified (of 23 items × 5 languages, 1/115 = 0.9%). For the RAID (simplified protocol) two problematic items were identified (of 7 items × 6 languages, 2/42 = 4.8%), of which one was revised (Dutch). Coping questions were problematic in both PROMs. Conceptual and cultural challenges though rare were important, as identified by formal evaluation, demonstrating that cognitive interviewing is crucial in PROM translations. Proportionately fewer problematic items were found for the full than for the simplified translation procedure, suggesting that while both are acceptable, professional PROM translation might be preferable. Coping may be a particularly challenging notion cross-culturally. © The Author 2016. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Obstructive Sleep Apnea and 15-Year Cognitive Decline: The Atherosclerosis Risk in Communities (ARIC) Study

PubMed Central

Lutsey, Pamela L.; Bengtson, Lindsay G.S.; Punjabi, Naresh M.; Shahar, Eyal; Mosley, Thomas H.; Gottesman, Rebecca F.; Wruck, Lisa M.; MacLehose, Richard F.; Alonso, Alvaro

2016-01-01

Study Objectives: Prospective data evaluating abnormal sleep quality and quantity with cognitive decline are limited because most studies used subjective data and/or had short follow-up. We hypothesized that, over 15 y of follow-up, participants with objectively measured obstructive sleep apnea (OSA) and other indices of poor sleep quantity and quality would experience greater decline in cognitive functioning than participants with normal sleep patterns. Methods: ARIC participants (n = 966; mean age 61 y, 55% women) with in-home polysomnography (1996–1998) and repeated cognitive testing were followed for 15 y. Three cognitive tests (Delayed Word Recall, Word Fluency, and Digit Symbol Substitution) were administered at two time points (1996–1998 and 2011–2013). Ten additional cognitive tests were administered at the 2011–2013 neurocognitive examination. OSA was modeled using established clinical OSA severity categories. Multivariable linear regression was used to explore associations of OSA and other sleep indices with change in cognitive tests between the two assessments. Results: A median of 14.9 y (max: 17.3) passed between the two cognitive assessments. OSA category and additional indices of sleep (other measures of hypoxemia and disordered breathing, sleep fragmentation, sleep duration) were not associated with change in any cognitive test. Analyses of OSA severity categories and 10 cognitive tests administered only in 2011–2013 also showed little evidence of an association. Conclusions: Overall, abnormal sleep quality and quantity at midlife was not related to cognitive decline and later-life cognition. The effect of adverse sleep quality and quantity on cognitive decline among the elderly remains to be determined. Citation: Lutsey PL, Bengtson LG, Punjabi NM, Shahar E, Mosley TH, Gottesman RF, Wruck LM, MacLehose RF, Alonso A. Obstructive sleep apnea and 15-year cognitive decline: the Atherosclerosis Risk in Communities (ARIC) study. SLEEP 2016;39(2):309–316. PMID:26446113

Improved Wireless Security through Physical Layer Protocol Manipulation and Radio Frequency Fingerprinting

DTIC Science & Technology

2014-09-18

radios in a cognitive radio network using a radio frequency fingerprinting based method. In IEEE International Conference on Communications (ICC...IMPROVEDWIRELESS SECURITY THROUGH PHYSICAL LAYER PROTOCOL MANIPULATION AND RADIO FREQUENCY FINGERPRINTING DISSERTATION Benjamin W. Ramsey, Captain...PHYSICAL LAYER PROTOCOL MANIPULATION AND RADIO FREQUENCY FINGERPRINTING DISSERTATION Presented to the Faculty Graduate School of Engineering and

Highly stable maintenance of a mouse artificial chromosome in human cells and mice.

PubMed

Kazuki, Kanako; Takehara, Shoko; Uno, Narumi; Imaoka, Natsuko; Abe, Satoshi; Takiguchi, Masato; Hiramatsu, Kei; Oshimura, Mitsuo; Kazuki, Yasuhiro

2013-12-06

Human artificial chromosomes (HACs) and mouse artificial chromosomes (MACs) display several advantages as gene delivery vectors, such as stable episomal maintenance that avoids insertional mutations and the ability to carry large gene inserts including the regulatory elements. Previously, we showed that a MAC vector developed from a natural mouse chromosome by chromosome engineering was more stably maintained in adult tissues and hematopoietic cells in mice than HAC vectors. In this study, to expand the utility for a gene delivery vector in human cells and mice, we investigated the long-term stability of the MACs in cultured human cells and transchromosomic mice. We also investigated the chromosomal copy number-dependent expression of genes on the MACs in mice. The MAC was stably maintained in human HT1080 cells in vitro during long-term culture. The MAC was stably maintained at least to the F8 and F4 generations in ICR and C57BL/6 backgrounds, respectively. The MAC was also stably maintained in hematopoietic cells and tissues derived from old mice. Transchromosomic mice containing two or four copies of the MAC were generated by breeding. The DNA contents were comparable to the copy number of the MACs in each tissue examined, and the expression of the EGFP gene on the MAC was dependent on the chromosomal copy number. Therefore, the MAC vector may be useful not only for gene delivery in mammalian cells but also for animal transgenesis. Copyright © 2013 Elsevier Inc. All rights reserved.

Protocol for a randomized controlled trial of piano training on cognitive and psychosocial outcomes.

PubMed

Bugos, Jennifer

2018-05-09

Age-related cognitive decline and cognitive impairment represent the fastest growing health epidemic worldwide among those over 60. There is a critical need to identify effective and novel complex cognitive interventions to promote successful aging. Since piano training engages cognitive and bimanual sensorimotor processing, we hypothesize that piano training may serve as an effective cognitive intervention, as it requires sustained attention and engages an executive network that supports generalized cognition and emotional control. Here, I describe the protocol of a randomized controlled trial (RCT) to evaluate the impact of piano training on cognitive performance in adulthood, a period associated with decreased neuroplasticity. In this cluster RCT, healthy older adults (age 60-80) were recruited and screened to control for confounding variables. Eligible participants completed an initial 3-h assessment of standardized cognitive and psychosocial measures. Participants were stratified by age, education, and estimate of intelligence and randomly assigned to one of three groups: piano training, computer brain training, or a no-treatment control group. Computer brain training consisted of progressively difficult auditory cognitive exercises (Brain HQ; Posit Science, 2010). Participants assigned to training groups completed a 16-week program that met twice a week for 90 minutes. Upon program completion and at a 3-month follow-up, training participants and no-treatment controls completed a posttest visit lasting 2.5 hours. © 2018 New York Academy of Sciences.

A mutation spectrum that includes GNAS, KRAS and TP53 may be shared by mucinous neoplasms of the appendix.

PubMed

Hara, Kieko; Saito, Tsuyoshi; Hayashi, Takuo; Yimit, Alkam; Takahashi, Michiko; Mitani, Keiko; Takahashi, Makoto; Yao, Takashi

2015-09-01

Appendiceal mucinous tumors (AMTs) are classified as low-grade appendiceal mucinous neoplasms (LAMNs) or mucinous adenocarcinomas (MACs), although their carcinogenesis is not well understood. As somatic activating mutations of GNAS are considered to be characteristic of LAMNs while TP53 mutations have been shown to be specific to MACs, MACs are unlikely to result from transformation of LAMNs. However, emerging evidence also shows the presence of GNAS mutations in MACs. We examined 16 AMTs (11 LAMNs and 5 MACs) for genetic alterations of GNAS, KRAS, BRAF, TP53, CTNNB1, and TERT promoter in order to elucidate the possibility of a shared genetic background in the two tumor types. Extensive histological examination revealed the presence of a low-grade component in all cases of MAC. GNAS mutations were detected in two LAMNs and in one MAC, although the GNAS mutation in this MAC was a nonsense mutation (Q227X) expected not to be activating mutation. TP53 mutations were detected in three LAMNs; they were frequently detected in MACs. KRAS mutations were detected in three LAMNs and three MACs, and CTNNB1 mutations were detected in two LAMNs. KRAS mutation and activating mutation of GNAS occurred exclusively in AMTs. BRAF and TERT mutations were not detected. Overexpression of p53 was observed in only two MACs, and p53 immunostaining clearly discriminated the high-grade lesion from a low-grade component in one. These findings suggest that p53 overexpression plays an important role in the carcinogenesis of AMTs and that, in addition to mutations of GNAS, KRAS and TP53 alterations might be shared by AMTs, thus providing evidence for the possible progression of LAMNs to MAC. Copyright © 2015 Elsevier GmbH. All rights reserved.

Cognitive functioning over 2 years after intracerebral hemorrhage in school-aged children.

PubMed

Murphy, Lexa K; Compas, Bruce E; Gindville, Melissa C; Reeslund, Kristen L; Jordan, Lori C

2017-11-01

Previous research investigating outcomes after pediatric intracerebral hemorrhage (ICH) has generally been limited to global and sensorimotor outcomes. This study examined cognitive outcomes after spontaneous ICH in school-aged children with serial assessments over 2 years after stroke. Seven children (age range 6-16y, median 13; six males, one female; 57% white, 43% black) presenting with spontaneous ICH (six arteriovenous malformations) were assessed at 3 months, 12 months, and 24 months after stroke. The Pediatric Stroke Outcome Measure (PSOM) quantified neurological outcome and Wechsler Intelligence Scales measured cognitive outcomes: verbal comprehension, perceptual reasoning, working memory, and processing speed. PSOM scales showed improved neurological function over the first 12 months, with mild to no sensorimotor deficits and moderate overall deficits at 1- and 2-year follow-ups (median 2-year sensorimotor PSOM=0.5, total PSOM=1.5). Changes in cognitive function indicated a different trajectory; verbal comprehension and perceptual reasoning improved over 24 months; low performance was sustained in processing speed and working memory. Age-normed centile scores decreased between 1- and 2-year follow-ups for working memory, suggesting emerging deficits compared with peers. Early and serial cognitive testing in children with ICH is needed to assess cognitive functioning and support children in school as they age and cognitive deficits become more apparent and important for function. In children with intracerebral hemorrhage (ICH), motor function improved between 3 months and 24 months. Improvements in cognitive function were variable between 3 months and 24 months. Working memory centiles declined, suggesting emerging deficits compared with peers. Processing speed improved but remained significantly below the 50th centile. Cognitive impact of ICH may increase with age in children. © 2017 Mac Keith Press.

Evolutionary cognitive therapy versus standard cognitive therapy for depression: a protocol for a blinded, randomized, superiority clinical trial.

PubMed

Giosan, Cezar; Cobeanu, Oana; Mogoase, Cristina; Muresan, Vlad; Malta, Loretta S; Wyka, Katarzyna; Szentagotai, Aurora

2014-03-19

Depression is estimated to become the leading cause of disease burden globally by 2030. Despite existing efficacious treatments (both medical and psychotherapeutic), a large proportion of patients do not respond to therapy. Recent insights from evolutionary psychology suggest that, in addition to targeting the proximal causes of depression (for example, targeting dysfunctional beliefs by cognitive behavioral therapy), the distal or evolutionary causes (for example, inclusive fitness) should also be addressed. A randomized superiority trial is conducted to develop and test an evolutionary-driven cognitive therapy protocol for depression, and to compare its efficacy against standard cognitive therapy for depression. Romanian-speaking adults (18 years or older) with elevated Beck Depression Inventory (BDI) scores (>13), current diagnosis of major depressive disorder or major depressive episode (MDD or MDE), and MDD with comorbid dysthymia, as evaluated by the Structured Clinical Interview for DSM-IV (SCID), are included in the study. Participants are randomized to one of two conditions: 1) evolutionary-driven cognitive therapy (ED-CT) or 2) cognitive therapy (CT). Both groups undergo 12 psychotherapy sessions, and data are collected at baseline, mid-treatment, post-treatment, and the 3-month follow-up. Primary outcomes are depressive symptomatology and a categorical diagnosis of depression post-treatment. This randomized trial compares the newly proposed ED-CT with a classic CT protocol for depression. To our knowledge, this is the first attempt to integrate insights from evolutionary theories of depression into the treatment of this condition in a controlled manner. This study can thus add substantially to the body of knowledge on validated treatments for depression. Current Controlled Trials ISRCTN64664414The trial was registered in June 2013. The first participant was enrolled on October 3, 2012.

Structure of the MacAB-TolC ABC-type tripartite multidrug efflux pump

PubMed Central

Llabrés, Salomé; Neuberger, Arthur; Blaza, James N.; Bai, Xiao-chen; Okada, Ui; Murakami, Satoshi; van Veen, Hendrik W.; Zachariae, Ulrich; Scheres, Sjors H.W.; Luisi, Ben F.

2017-01-01

The MacA-MacB-TolC assembly of Escherichia coli is a transmembrane machine that spans the cell envelope and actively extrudes substrates, including macrolide antibiotics and polypeptide virulence factors. These transport processes are energized by the ATPase MacB, a member of the ATP-binding cassette (ABC) superfamily. We present an electron cryo-microscopy structure of the ABC-type tripartite assembly at near-atomic resolution. A hexamer of the periplasmic protein MacA bridges between a TolC trimer in the outer membrane and a MacB dimer in the inner membrane, generating a quaternary structure with a central channel for substrate translocation. A gating ring found in MacA is proposed to act as a one-way valve in substrate transport. The MacB structure features an atypical transmembrane domain (TMD) with a closely packed dimer interface and a periplasmic opening that is the likely portal for substrate entry from the periplasm, with subsequent displacement through an allosteric transport mechanism. PMID:28504659

Carbon nanotube-clamped metal atomic chain

PubMed Central

Tang, Dai-Ming; Yin, Li-Chang; Li, Feng; Liu, Chang; Yu, Wan-Jing; Hou, Peng-Xiang; Wu, Bo; Lee, Young-Hee; Ma, Xiu-Liang; Cheng, Hui-Ming

2010-01-01

Metal atomic chain (MAC) is an ultimate one-dimensional structure with unique physical properties, such as quantized conductance, colossal magnetic anisotropy, and quantized magnetoresistance. Therefore, MACs show great potential as possible components of nanoscale electronic and spintronic devices. However, MACs are usually suspended between two macroscale metallic electrodes; hence obvious technical barriers exist in the interconnection and integration of MACs. Here we report a carbon nanotube (CNT)-clamped MAC, where CNTs play the roles of both nanoconnector and electrodes. This nanostructure is prepared by in situ machining a metal-filled CNT, including peeling off carbon shells by spatially and elementally selective electron beam irradiation and further elongating the exposed metal nanorod. The microstructure and formation process of this CNT-clamped MAC are explored by both transmission electron microscopy observations and theoretical simulations. First-principles calculations indicate that strong covalent bonds are formed between the CNT and MAC. The electrical transport property of the CNT-clamped MAC was experimentally measured, and quantized conductance was observed. PMID:20427743

An energy-efficient transmission scheme for real-time data in wireless sensor networks.

PubMed

Kim, Jin-Woo; Barrado, José Ramón Ramos; Jeon, Dong-Keun

2015-05-20

The Internet of things (IoT) is a novel paradigm where all things or objects in daily life can communicate with other devices and provide services over the Internet. Things or objects need identifying, sensing, networking and processing capabilities to make the IoT paradigm a reality. The IEEE 802.15.4 standard is one of the main communication protocols proposed for the IoT. The IEEE 802.15.4 standard provides the guaranteed time slot (GTS) mechanism that supports the quality of service (QoS) for the real-time data transmission. In spite of some QoS features in IEEE 802.15.4 standard, the problem of end-to-end delay still remains. In order to solve this problem, we propose a cooperative medium access scheme (MAC) protocol for real-time data transmission. We also evaluate the performance of the proposed scheme through simulation. The simulation results demonstrate that the proposed scheme can improve the network performance.

An Energy-Efficient Transmission Scheme for Real-Time Data in Wireless Sensor Networks

PubMed Central

Kim, Jin-Woo; Barrado, José Ramón Ramos; Jeon, Dong-Keun

2015-01-01

The Internet of things (IoT) is a novel paradigm where all things or objects in daily life can communicate with other devices and provide services over the Internet. Things or objects need identifying, sensing, networking and processing capabilities to make the IoT paradigm a reality. The IEEE 802.15.4 standard is one of the main communication protocols proposed for the IoT. The IEEE 802.15.4 standard provides the guaranteed time slot (GTS) mechanism that supports the quality of service (QoS) for the real-time data transmission. In spite of some QoS features in IEEE 802.15.4 standard, the problem of end-to-end delay still remains. In order to solve this problem, we propose a cooperative medium access scheme (MAC) protocol for real-time data transmission. We also evaluate the performance of the proposed scheme through simulation. The simulation results demonstrate that the proposed scheme can improve the network performance. PMID:26007722

Wireless optical network for a home network

NASA Astrophysics Data System (ADS)

Bouchet, Olivier; Porcon, Pascal; Walewski, Joachim W.; Nerreter, Stefan; Langer, Klaus-Dieter; Fernández, Luz; Vucic, Jelena; Kamalakis, Thomas; Ntogari, Georgia; Neokosmidis, Ioannis; Gueutier, Eric

2010-08-01

During the European collaborative project OMEGA, two optical-wireless prototypes have been developed. The first prototype operates in the near-infrared spectral region and features Giga Ethernet connectivity, a simple transceiver architecture due to the use of on-off keying, a multi-sector transceiver, and an ultra-fast switch for sector-to-sector hand over. This full-duplex system, composed by one base station and one module, transmits data on three meters. The second prototype is a visible-light-communications system based on DMT signal processing and an adapted MAC sublayer. Data rates around to 100 Mb/s at the physical layer are achieved. This broadcast system, composed also by one base station and one module, transmits data up to two meters. In this paper we present the adapted optical wireless media-access-control sublayer protocol for visible-light communications. This protocol accommodates link adaptation from 128 Mb/s to 1024 Mb/s with multi-sector coverage, and half-duplex or full-duplex transmission.

Effects of metabolic acidosis on intracellular pH responses in multiple cell types

PubMed Central

Salameh, Ahlam Ibrahim; Ruffin, Vernon A.

2014-01-01

Metabolic acidosis (MAc), a decrease in extracellular pH (pHo) caused by a decrease in [HCO3−]o at a fixed [CO2]o, is a common clinical condition and causes intracellular pH (pHi) to fall. Although previous work has suggested that MAc-induced decreases in pHi (ΔpHi) differ among cell types, what is not clear is the extent to which these differences are the result of the wide variety of methodologies employed by various investigators. In the present study, we evaluated the effects of two sequential MAc challenges (MAc1 and MAc2) on pHi in 10 cell types/lines: primary-cultured hippocampal (HCN) neurons and astrocytes (HCA), primary-cultured medullary raphé (MRN) neurons, and astrocytes (MRA), CT26 colon cancer, the C2C12 skeletal muscles, primary-cultured bone marrow-derived macrophages (BMDM) and dendritic cells (BMDC), Ink4a/ARF-null melanocytes, and XB-2 keratinocytes. We monitor pHi using ratiometric fluorescence imaging of 2′,7′-bis-(2-carboxyethyl)-5-(and-6)-carboxyfluorescein while imposing MAc: lowering (pHo) from 7.4 to 7.2 by decreasing [HCO3−]o from 22 to 14 mM at 5% CO2 for 7 min. After MAc1, we return cells to the control solution for 10 min and impose MAc2. Using our definition of MAc resistance [(ΔpHi/ΔpHo) ≤ 40%], during MAc1, ∼70% of CT26 and ∼50% of C2C12 are MAc-resistant, whereas the other cell types are predominantly MAc-sensitive. During MAc2, some cells adapt [(ΔpHi/ΔpHo)2 < (ΔpHi/ΔpHo)1], particularly HCA, C2C12, and BMDC. Most maintain consistent responses [(ΔpHi/ΔpHo)2 ≅ (ΔpHi/ΔpHo)1], and a few decompensate [(ΔpHi/ΔpHo)2>(ΔpHi/ΔpHo)1], particularly HCN, C2C12, and XB-2. Thus, responses to twin MAc challenges depend both on the individual cell and cell type. PMID:25209413

Progranulin levels in blood in Alzheimer's disease and mild cognitive impairment.

PubMed

Cooper, Yonatan A; Nachun, Daniel; Dokuru, Deepika; Yang, Zhongan; Karydas, Anna M; Serrero, Ginette; Yue, Binbin; Boxer, Adam L; Miller, Bruce L; Coppola, Giovanni

2018-05-01

Changes in progranulin ( GRN ) expression have been hypothesized to alter risk for Alzheimer's disease (AD). We investigated the relationship between GRN expression in peripheral blood and clinical diagnosis of AD and mild cognitive impairment (MCI). Peripheral blood progranulin gene expression was measured, using microarrays from Alzheimer's ( n = 186), MCI ( n = 118), and control ( n = 204) subjects from the University of California San Francisco Memory and Aging Center (UCSF-MAC) and two independent published series (AddNeuroMed and ADNI). GRN gene expression was correlated with clinical, demographic, and genetic data, including APOE haplotype and the GRN rs5848 single-nucleotide polymorphism. Finally, we assessed progranulin protein levels, using enzyme-linked immunosorbent assay, and methylation status using methylation microarrays. We observed an increase in blood progranulin gene expression and a decrease in GRN promoter methylation in males ( P = 0.007). Progranulin expression was 13% higher in AD and MCI patients compared with controls in the UCSF-MAC cohort ( F 2,505 = 10.41, P = 3.72*10 -5 ). This finding was replicated in the AddNeuroMed ( F 2,271 = 17.9, P = 4.83*10 -8 ) but not the ADNI series. The rs5848 SNP (T-allele) predicted decreased blood progranulin gene expression ( P = 0.03). The APOE4 haplotype was positively associated with progranulin expression independent of diagnosis ( P = 0.04). Finally, we did not identify differences in plasma progranulin protein levels or gene methylation between diagnostic categories. Progranulin mRNA is elevated in peripheral blood of patients with AD and MCI and its expression is associated with numerous genetic and demographic factors. These data suggest a role in the pathogenesis of neurodegenerative dementias besides frontotemporal dementia.

[Mental capacity and capacity to consent: multicentric study in a involuntary psychiatric hospitalized patients sample].

PubMed

Carabellese, Felice; Mandarelli, Gabriele; La Tegola, Donatella; Parmigiani, Giovanna; Ferracuti, Stefano; Quartesan, Roberto; Bellomo, Antonello; Catanesi, Roberto

2017-01-01

The purpose of this longitudinal observational study is to evaluate the course and impact of clinical, social, and behavioral variables on the involuntary readmission of psychiatric patients, during a 6-months follow-up after discharge from a prior involuntary hospitalization. N=131 involuntarily committed psychiatric patients were enrolled in three university hospitals (Bari n=57; Perugia n=42; Rome n=32). At the first assessment cognitive functioning (MMSE), psychiatric symptoms severity (BPRS-E), capacity to consent to treatment (MacCAT-T) as well as principal socio-demographic and clinical variables were collected. At 6-months follow-up, we collected data concerning involuntary psychiatric readmissions, pharmacotherapy adherence, new deliberate self-harm or harm to others as well as having been legally prosecuted. N=120 patients were reevaluated at follow-up (M=188 days, SD=12.6); among these n=15 (12.5%) have had a new involuntary psychiatric admission due to an acute mental disorder. Re-hospitalized patients showed higher rates of harm to others (p<0.05) and legal prosecution (p<0.05); there was moreover a trend toward higher pharmacological dropout rates in involuntarily rehospitalized patients. We found no differences between the two groups in baseline psychiatric symptoms severity and cognitive functioning, whereas involuntary re-hospitalization was associated with more frequent involuntary hospitalization during last year (p<0.05) and higher MacCAT-T reasoning (p<0.05). Involuntary psychiatric readmission rates proved to be poorly associated with clinical features assessed during previous hospitalization. Our data suggest that social and legal factors, including those connected to patients' dangerousness, could play a role also in a civil commitment system based solely on the need for treatment.

Can maintaining cognitive function at 65 years old predict successful ageing 6 years later? The PROOF study.

PubMed

Castro-Lionard, Karine; Thomas-Antérion, Catherine; Crawford-Achour, Emilie; Rouch, Isabelle; Trombert-Paviot, Béatrice; Barthélémy, Jean-Claude; Laurent, Bernard; Roche, Frédéric; Gonthier, Régis

2011-03-01

preservation of cognitive abilities is required to have a good quality of life. The predictive value of cognitive functioning at 65 years old on successful ageing 6 years later is not established. nine hundred and seventy-six questionnaires were sent by mail to a sample of healthy and voluntary French pensioners. Successful ageing was defined through health status and well-being. Cognitive abilities had been assessed 6 years earlier according to an objective method (Free and Cued Selective Recall Reminding Test (FCSRT), the Benton visual retention test and the similarities subtest of the Wechsler Adult Intelligence Scale-Revised) and a subjective one (Goldberg's anxiety scale, Mac Nair's scale and a Visual Analogue Scale to evaluate memory abilities change in the last 5 years). six hundred and eighty-six questionnaires could be analysed. The mean age was 72.9 ± 1.2 years old with 59% of women and 99% lived at home. Well-being was negatively correlated with the FCSRT (r = -0.08, P = 0.0318) but positively related with the Benton (r = 0.09, P = 0.0125) and the similarities tests (r = 0.09, P = 0.0118). There is a negative correlation between anxious and cognitive complaints measured at baseline, and successful ageing indicators 6 years later. preservation of cognitive abilities at the age of retirement can predict a successful ageing 6 years later. ClinicalTrials.gov Identifier: NCT00759304.

GENETIC FINGERPRINTING OF MYCOBACTERIUM AVIUM COMPLEX (MAC) ORGANISMS ISOLATED FROM HOSPITAL PATIENTS AND THE ENVIRONMENT

EPA Science Inventory

A particularly pathogenic group of mycobacteria belong to the Mycobacterium avium complex (MAC), which includes M. avium and M. intracellulare. MAC organisms cause disease in children, the elderly, and immuno-compromised individuals. A critical step in preventing MAC infections...

Discriminative validity of the MacAndrew Alcoholism Scale with Cluster B personality disorders.

PubMed

Smith, S R; Hilsenroth, M J

2001-06-01

This study was designed to assess the ability of the Minnesota Multiphasic Personality Inventory (MMPI-2) MacAndrew Alcoholism Scale (MAC-R) to differentiate between outpatients with personality disorders with Substance-Related Disorders (SRDs) and without SRDs. MMPI-2 validity, clinical, and MAC-R scale scores were compared in an SRD Cluster B group (comprised of Narcissistic, Antisocial, Borderline, and Histrionic; n = 15), a non-SRD Cluster B group (n = 33), and a non-SRD group with personality disorders from Clusters A and C (n = 18). Results revealed that the substance-abusing Cluster B group scored significantly higher on the MAC-R ( p <.0001) as well as the Psychopathic Deviate scale ( p <.01). Dimensional analyses illustrated that MAC-R scores were related to the presence of an SRD diagnosis (rpb =.70, p <.0001) and diagnostic criteria for Antisocial Personality Disorder (r =.60, p <.0001). Stepwise regression revealed that (in order of magnitude) the presence of a substance-abuse diagnosis followed by diagnostic criteria for Antisocial and Histrionic Personality Disorders were most related to MAC-R scores (R =.78, R(2) =.60). This indicates that the MAC-R may be more related to the presence of an SRD than has been suggested, and when used in outpatient settings as MacAndrew (1965) intended, the MAC-R may be useful as a screening device for assessing SRD among outpatients with Axis II psychopathology.

Automated, Quantitative Cognitive/Behavioral Screening of Mice: For Genetics, Pharmacology, Animal Cognition and Undergraduate Instruction

PubMed Central

Gallistel, C. R.; Balci, Fuat; Freestone, David; Kheifets, Aaron; King, Adam

2014-01-01

We describe a high-throughput, high-volume, fully automated, live-in 24/7 behavioral testing system for assessing the effects of genetic and pharmacological manipulations on basic mechanisms of cognition and learning in mice. A standard polypropylene mouse housing tub is connected through an acrylic tube to a standard commercial mouse test box. The test box has 3 hoppers, 2 of which are connected to pellet feeders. All are internally illuminable with an LED and monitored for head entries by infrared (IR) beams. Mice live in the environment, which eliminates handling during screening. They obtain their food during two or more daily feeding periods by performing in operant (instrumental) and Pavlovian (classical) protocols, for which we have written protocol-control software and quasi-real-time data analysis and graphing software. The data analysis and graphing routines are written in a MATLAB-based language created to simplify greatly the analysis of large time-stamped behavioral and physiological event records and to preserve a full data trail from raw data through all intermediate analyses to the published graphs and statistics within a single data structure. The data-analysis code harvests the data several times a day and subjects it to statistical and graphical analyses, which are automatically stored in the "cloud" and on in-lab computers. Thus, the progress of individual mice is visualized and quantified daily. The data-analysis code talks to the protocol-control code, permitting the automated advance from protocol to protocol of individual subjects. The behavioral protocols implemented are matching, autoshaping, timed hopper-switching, risk assessment in timed hopper-switching, impulsivity measurement, and the circadian anticipation of food availability. Open-source protocol-control and data-analysis code makes the addition of new protocols simple. Eight test environments fit in a 48 in x 24 in x 78 in cabinet; two such cabinets (16 environments) may be controlled by one computer. PMID:24637442

Automated, quantitative cognitive/behavioral screening of mice: for genetics, pharmacology, animal cognition and undergraduate instruction.

PubMed

Gallistel, C R; Balci, Fuat; Freestone, David; Kheifets, Aaron; King, Adam

2014-02-26

We describe a high-throughput, high-volume, fully automated, live-in 24/7 behavioral testing system for assessing the effects of genetic and pharmacological manipulations on basic mechanisms of cognition and learning in mice. A standard polypropylene mouse housing tub is connected through an acrylic tube to a standard commercial mouse test box. The test box has 3 hoppers, 2 of which are connected to pellet feeders. All are internally illuminable with an LED and monitored for head entries by infrared (IR) beams. Mice live in the environment, which eliminates handling during screening. They obtain their food during two or more daily feeding periods by performing in operant (instrumental) and Pavlovian (classical) protocols, for which we have written protocol-control software and quasi-real-time data analysis and graphing software. The data analysis and graphing routines are written in a MATLAB-based language created to simplify greatly the analysis of large time-stamped behavioral and physiological event records and to preserve a full data trail from raw data through all intermediate analyses to the published graphs and statistics within a single data structure. The data-analysis code harvests the data several times a day and subjects it to statistical and graphical analyses, which are automatically stored in the "cloud" and on in-lab computers. Thus, the progress of individual mice is visualized and quantified daily. The data-analysis code talks to the protocol-control code, permitting the automated advance from protocol to protocol of individual subjects. The behavioral protocols implemented are matching, autoshaping, timed hopper-switching, risk assessment in timed hopper-switching, impulsivity measurement, and the circadian anticipation of food availability. Open-source protocol-control and data-analysis code makes the addition of new protocols simple. Eight test environments fit in a 48 in x 24 in x 78 in cabinet; two such cabinets (16 environments) may be controlled by one computer.

Clinical efficacy of anti-glycopeptidolipid-core IgA test for diagnosing Mycobacterium avium complex infection in lung.

PubMed

Numata, Takanori; Araya, Jun; Yoshii, Yutaka; Shimizu, Kenichiro; Hara, Hiromichi; Nakayama, Katsutoshi; Kuwano, Kazuyoshi

2015-11-01

It is difficult to verify the bacteriological diagnosis of Mycobacterium avium complex (MAC) infection. The anti-glycopeptidolipid (GPL)-core IgA antibody test was recently developed as a diagnostic method for MAC pulmonary disease. Only a few studies evaluate its clinical efficacy. We conducted retrospective evaluations of clinical characteristics of patients suspected of MAC infection to explore the usefulness of the anti-GPL-core IgA antibody test. We retrospectively evaluated 296 patients who were suspected to have MAC infection and underwent anti-GPL-core IgA antibody test between March 2013 and July 2014 in Jikei University hospital. A total of 29 patients were diagnosed with 'definite MAC' based on the American Thoracic Society (ATS) criteria with multiple identifications of MAC. On the other hand, 106 patients were diagnosed with other pulmonary diseases than MAC. The sensitivity and specificity of anti-GPL-core IgA antibody test for MAC diagnosis were 58.6% and 98.1%, respectively. The definite MAC group showed no significant differences in strains, treatment history or number of segments involved. The duration of MAC disease in the positive-antibody group was significantly longer than in the negative-antibody group (P = 0.046). A significant increase in the false-negative rate was observed in patients with malignant disease (P = 0.029). The anti-GPL-core IgA antibody test demonstrated high sensitivity and specificity for the diagnosis of MAC infection especially in patients without malignant diseases. © 2015 Asian Pacific Society of Respirology.

The Leishmania donovani histidine acid ecto-phosphatase LdMAcP: insight into its structure and function.

PubMed

Papadaki, Amalia; Politou, Anastasia S; Smirlis, Despina; Kotini, Maria P; Kourou, Konstadina; Papamarcaki, Thomais; Boleti, Haralabia

2015-05-01

Acid ecto-phosphatase activity has been implicated in Leishmania donovani promastigote virulence. In the present study, we report data contributing to the molecular/structural and functional characterization of the L. donovani LdMAcP (L. donovani membrane acid phosphatase), member of the histidine acid phosphatase (HAcP) family. LdMAcP is membrane-anchored and shares high sequence identity with the major secreted L. donovani acid phosphatases (LdSAcPs). Sequence comparison of the LdMAcP orthologues in Leishmania sp. revealed strain polymorphism and species specificity for the L. donovani complex, responsible for visceral leishmaniasis (Khala azar), proposing thus a potential value of LdMAcP as an epidemiological or diagnostic tool. The extracellular orientation of the LdMAcP catalytic domain was confirmed in L. donovani promastigotes, wild-type (wt) and transgenic overexpressing a recombinant LdMAcP-mRFP1 (monomeric RFP1) chimera, as well as in transiently transfected mammalian cells expressing rLdMAcP-His. For the first time it is demonstrated in the present study that LdMAcP confers tartrate resistant acid ecto-phosphatase activity in live L. donovani promastigotes. The latter confirmed the long sought molecular identity of at least one enzyme contributing to this activity. Interestingly, the L. donovani rLdMAcP-mRFP1 promastigotes generated in this study, showed significantly higher infectivity and virulence indexes than control parasites in the infection of J774 mouse macrophages highlighting thereby a role for LdMAcP in the parasite's virulence.

Functional characterization of the copper transcription factor AfMac1 from Aspergillus fumigatus.

PubMed

Park, Yong-Sung; Kim, Tae-Hyoung; Yun, Cheol-Won

2017-07-03

Although copper functions as a cofactor in many physiological processes, copper overload leads to harmful effects in living cells. Thus, copper homeostasis is tightly regulated. However, detailed copper metabolic pathways have not yet been identified in filamentous fungi. In this report, we investigated the copper transcription factor AfMac1 ( A spergillus f umigatus Mac1 homolog) and identified its regulatory mechanism in A. fumigatus AfMac1 has domains homologous to the DNA-binding and copper-binding domains of Mac1 from Saccharomyces cerevisiae , and AfMac1 efficiently complemented Mac1 in S. cerevisiae Expression of Afmac1 resulted in CTR1 up-regulation, and mutation of the DNA-binding domain of Afmac1 failed to activate CTR1 expression in S. cerevisiae The Afmac1 deletion strain of A. fumigatus failed to grow in copper-limited media, and its growth was restored by introducing ctrC We found that AfMac1 specifically bound to the promoter region of ctrC based on EMSA. The AfMac1-binding motif 5'-TGTGCTCA-3' was identified from the promoter region of ctrC , and the addition of mutant ctrC lacking the AfMac1-binding motif failed to up-regulate ctrC in A. fumigatus Furthermore, deletion of Afmac1 significantly reduced strain virulence and activated conidial killing activity by neutrophils and macrophages. Taken together, these results suggest that AfMac1 is a copper transcription factor that regulates cellular copper homeostasis in A. fumigatus . © 2017 The Author(s); published by Portland Press Limited on behalf of the Biochemical Society.

An observational study on patient admission in the anaesthesia gas monitor and minimum alveolar concentration monitoring: A deficiency with huge impact

PubMed Central

Karim, Habib Md Reazaul; Narayan, Anilkumar; Yunus, Md; Kumar, Sanjay; Prakash, Avinash; Sahoo, Sarasa Kumar

2017-01-01

Background and Aims: Minimum alveolar concentration (MAC) monitoring is an integral part of modern-day anaesthesia. Both MAC and MAC-awake are age dependant, and age of the patient needs to be entered in the monitor. This study was aimed to assess the practice of patient birth year entry in the anaesthesia monitor and its impact on MAC monitoring. Methods: Sixty volatile anaesthetic-based general anaesthetics (GAs) were observed silently in two tertiary care teaching hospitals with regard to ‘birth year’ entry in the patient monitor. The impact on MAC for non-entry of age was assessed. The observed MAC reading and the MAC corrected for age (MACage) of the patients were noted. Paired t-test was used to compare the differences in observed MAC and MACage values. P <0.05 was significant. Results: Sixty GAs of patients aged between 10 and 68 years were observed; 96.67% anaesthetics were conducted without entering ‘birth year’. Thirty-four patients (mean age 35.14 ± 15.38 years) were further assessed for impact of non-entry of age. The observed MAC was similar to MACage in patients aged 40 ± 5 years (36–45 years group). Nearly 79.41% of the observed MACs were incorrect; 55.88% patients were potentially underdosed whereas 23.53% were overdosed. Conclusion: Omitting patient age entry in the monitor results in erroneous MAC values, exposing patients <40 years to underdosing and older patients to overdose. PMID:28794529

Using Think-Aloud Protocols To Assess Cognitive Levels of Students in College Classrooms.

ERIC Educational Resources Information Center

Whittington, M. Susie

The cognitive levels of instruction of professors from the Pennsylvania Governor's School for the Agricultural Sciences (PGSAS) and the cognitive levels of thought among students were studied. The classes of 4 of 16 PGSAS professors were selected for analysis, and researchers recorded the frequency of observable teacher behaviors from each level…

78 FR 65541 - Federal Agricultural Mortgage Corporation Funding and Fiscal Affairs; Farmer Mac Liquidity...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-01

... Funding and Fiscal Affairs; Farmer Mac Liquidity Management AGENCY: Farm Credit Administration. ACTION... liquidity management regulations for the Federal Agricultural Mortgage Corporation (Farmer Mac). The purpose of the final rule is to strengthen liquidity risk management at Farmer Mac, improve the quality of...

Phase Relations and Miscibility in Polymer Blends Containing Copolymers.

DTIC Science & Technology

1986-04-15

MacKnight, W. J ., Pure Appl. Chem. 52, 409 (1980). 36. Vukovic , R., Kuresevic, V., Karasz, F. E., and MacKnight, W. J ., Thermochim. Acta 54, 349 (1982). 37... Vukovic , R., Karasz, F. E., and MacKnight, W. J ., Polymer 24, 529 (1983). 38. Vukovic , R., Karasz, F. E., and MacKnight, W. J ., J . Appl. Polymer Sci...28, 219 (1983). 39. Zacharius, S. L., ten Brinke, G., MacKnight, W. J ., and Karasz, F. E., Macromolecules 16, 381 (1983). 40. Vukovic , R., Kuresevic

Non-Orthogonal Random Access in MIMO Cognitive Radio Networks: Beamforming, Power Allocation, and Opportunistic Transmission

PubMed Central

Lin, Huifa; Shin, Won-Yong

2017-01-01

We study secondary random access in multi-input multi-output cognitive radio networks, where a slotted ALOHA-type protocol and successive interference cancellation are used. We first introduce three types of transmit beamforming performed by secondary users, where multiple antennas are used to suppress the interference at the primary base station and/or to increase the received signal power at the secondary base station. Then, we show a simple decentralized power allocation along with the equivalent single-antenna conversion. To exploit the multiuser diversity gain, an opportunistic transmission protocol is proposed, where the secondary users generating less interference are opportunistically selected, resulting in a further reduction of the interference temperature. The proposed methods are validated via computer simulations. Numerical results show that increasing the number of transmit antennas can greatly reduce the interference temperature, while increasing the number of receive antennas leads to a reduction of the total transmit power. Optimal parameter values of the opportunistic transmission protocol are examined according to three types of beamforming and different antenna configurations, in terms of maximizing the cognitive transmission capacity. All the beamforming, decentralized power allocation, and opportunistic transmission protocol are performed by the secondary users in a decentralized manner, thus resulting in an easy implementation in practice. PMID:28076402

Non-Orthogonal Random Access in MIMO Cognitive Radio Networks: Beamforming, Power Allocation, and Opportunistic Transmission.

PubMed

Lin, Huifa; Shin, Won-Yong

2017-01-01

We study secondary random access in multi-input multi-output cognitive radio networks, where a slotted ALOHA-type protocol and successive interference cancellation are used. We first introduce three types of transmit beamforming performed by secondary users, where multiple antennas are used to suppress the interference at the primary base station and/or to increase the received signal power at the secondary base station. Then, we show a simple decentralized power allocation along with the equivalent single-antenna conversion. To exploit the multiuser diversity gain, an opportunistic transmission protocol is proposed, where the secondary users generating less interference are opportunistically selected, resulting in a further reduction of the interference temperature. The proposed methods are validated via computer simulations. Numerical results show that increasing the number of transmit antennas can greatly reduce the interference temperature, while increasing the number of receive antennas leads to a reduction of the total transmit power. Optimal parameter values of the opportunistic transmission protocol are examined according to three types of beamforming and different antenna configurations, in terms of maximizing the cognitive transmission capacity. All the beamforming, decentralized power allocation, and opportunistic transmission protocol are performed by the secondary users in a decentralized manner, thus resulting in an easy implementation in practice.

Decision-making capacity for research participation among addicted people: a cross-sectional study.

PubMed

Morán-Sánchez, Inés; Luna, Aurelio; Sánchez-Muñoz, Maria; Aguilera-Alcaraz, Beatriz; Pérez-Cárceles, Maria D

2016-01-13

Informed consent is a key element of ethical clinical research. Addicted population may be at risk for impaired consent capacity. However, very little research has focused on their comprehension of consent forms. The aim of this study is to assess the capacity of addicted individuals to provide consent to research. 53 subjects with DSM-5 diagnoses of a Substance Use Disorder (SUD) and 50 non psychiatric comparison subjects (NPCs) participated in the survey from December 2014 to March 2015. This cross-sectional study was carried out at a community-based Outpatient Treatment Center and at an urban-located Health Centre in Spain. A binary judgment of capacity/incapacity was made guided by the MacArthur Competence Assessment Tool for Clinical Research (MacCAT-CR) and a clinical interview. Demographics and clinical characteristics were assessed by cases notes and the Mini-Mental State Examination, the Global Assessment Functional Scale and the Clinical Global Impression Scale. NPCs performed the best on the MacCAT-CR, and patients with SUD had the worst performance, particularly on the Understanding and Appreciation subscales. 32.7% SUD people lacked research-related decisional capacity. There were no statistically significant differences between the groups in terms of capacity to consent to research. The findings of our study provide evidence that a large proportion of individuals with SUD had decisional capacity for consent to research. It is therefore inappropriate to draw conclusions about capacity to make research decisions on the basis of a SUD diagnosis. In the absence of advanced cognitive impairment, acute withdrawal or intoxication, we should assume that addicted persons possess decision-making capacity. Thus, the view that people with SUD would ipso facto lose decision-making power for research consent is flawed and stigmatizing.

Q-Learning and p-persistent CSMA based rendezvous protocol for cognitive radio networks operating with shared spectrum activity

NASA Astrophysics Data System (ADS)

Watson, Clifton L.; Biswas, Subir

2014-06-01

With an increasing demand for spectrum, dynamic spectrum access (DSA) has been proposed as viable means for providing the flexibility and greater access to spectrum necessary to meet this demand. Within the DSA concept, unlicensed secondary users temporarily "borrow" or access licensed spectrum, while respecting the licensed primary user's rights to that spectrum. As key enablers for DSA, cognitive radios (CRs) are based on software-defined radios which allow them to sense, learn, and adapt to the spectrum environment. These radios can operate independently and rapidly switch channels. Thus, the initial setup and maintenance of cognitive radio networks are dependent upon the ability of CR nodes to find each other, in a process known as rendezvous, and create a link on a common channel for the exchange of data and control information. In this paper, we propose a novel rendezvous protocol, known as QLP, which is based on Q-learning and the p-persistent CSMA protocol. With the QLP protocol, CR nodes learn which channels are best for rendezvous and thus adapt their behavior to visit those channels more frequently. We demonstrate through simulation that the QLP protocol provides a rendevous capability for DSA environments with different dynamics of PU activity, while attempting to achieve the following performance goals: (1) minimize the average time-to-rendezvous, (2) maximize system throughput, (3) minimize primary user interference, and (4) minimize collisions among CR nodes.

Library Signage: Applications for the Apple Macintosh and MacPaint.

ERIC Educational Resources Information Center

Diskin, Jill A.; FitzGerald, Patricia

1984-01-01

Describes specific applications of the Macintosh computer at Carnegie-Mellon University Libraries, where MacPaint was used as a flexible, easy to use, and powerful tool to produce informational, instructional, and promotional signage. Profiles of system hardware and software, an evaluation of the computer program MacPaint, and MacPaint signage…

Antibiotic Resistance Mediated by the MacB ABC Transporter Family: A Structural and Functional Perspective.

PubMed

Greene, Nicholas P; Kaplan, Elise; Crow, Allister; Koronakis, Vassilis

2018-01-01

The MacB ABC transporter forms a tripartite efflux pump with the MacA adaptor protein and TolC outer membrane exit duct to expel antibiotics and export virulence factors from Gram-negative bacteria. Here, we review recent structural and functional data on MacB and its homologs. MacB has a fold that is distinct from other structurally characterized ABC transporters and uses a unique molecular mechanism termed mechanotransmission. Unlike other bacterial ABC transporters, MacB does not transport substrates across the inner membrane in which it is based, but instead couples cytoplasmic ATP hydrolysis with transmembrane conformational changes that are used to perform work in the extra-cytoplasmic space. In the MacAB-TolC tripartite pump, mechanotransmission drives efflux of antibiotics and export of a protein toxin from the periplasmic space via the TolC exit duct. Homologous tripartite systems from pathogenic bacteria similarly export protein-like signaling molecules, virulence factors and siderophores. In addition, many MacB-like ABC transporters do not form tripartite pumps, but instead operate in diverse cellular processes including antibiotic sensing, cell division and lipoprotein trafficking.

[Effects of xenon preconditioning against ischemia/reperfusion injury and oxidative stress in immature heart].

PubMed

Li, Qian; Lian, Chun-Wei; Fang, Li-Qun; Liu, Bin; Yang, Bo

2014-09-01

To investigate whether xenon preconditioning (PC) could protect immature myocardium against ischemia-reperfusion (I/R) injury in a dose-dependent manner and clarify the role of xenon PC on oxidative stress. Forty-eight isolated perfused immature rabbit hearts were randomly divided into four groups (n = 12): The sham group had the hearts perfused continuously for 300 min. In I/R group, the hearts were subjected to 60 min perfusion followed by 60 min ischemia and 180 min reperfusion. In 1 minimum alveolar concentration (MAC) and 0.5 MAC xenon PC groups, the hearts were preconditioned with 1 MAC or 0.5 MAC xenon respectively, following 60 min ischemia and 180 min reperfusion. The cardiac function, myocardial infarct size, mitochondrial structure, superoxide dismutase (SOD) activity and malondialdehyde (MDA) level in each group were determined after reperfusion. Compared with I/R group, both 1 MAC and 0. 5 MAC xenon preconditioning significantly improved cardiac function (P < 0.01), reduced myocardial infarct size (P < 0.01) and mitochondrial damage, increased SOD activity and decreased MDA level (P < 0.01). There were no differences between 1 MAC group and 0.5 MAC xenon group (P > 0.05). Xenon preconditioning at 0. 5 and 1 MAC produce similar cardioprotective effects against I/R injury in isolated perfused immature heart.

Current evidence for the use of C-MAC videolaryngoscope in adult airway management: a review of the literature

PubMed Central

Xue, Fu-Shan; Li, Hui-Xian; Liu, Ya-Yang; Yang, Gui-Zhen

2017-01-01

The C-MAC videolaryngoscope is the first Macintosh-typed videolaryngoscope. Since the advent of its original version video Macintosh system in 1999, this device has been modified several times. A unique feature of C-MAC device is its ability to provide the 2 options of direct and video laryngoscopy with the same device. The available evidence shows that in patients with normal airways, C-MAC videolaryngoscope compared with direct laryngoscopy can provide comparable or better laryngeal views and exerts less force on maxillary incisors, but does not offer conclusive benefits with regard to intubation time, intubation success, number of intubation attempts, the use of adjuncts, and hemodynamic responses to intubation. In patients with predicted or known difficult airways, C-MAC videolaryngoscope can achieve a better laryngeal view, a higher intubation success rate and a shorter intubation time than direct laryngoscopy. Furthermore, the option to perform direct and video laryngoscopy with the same device makes C-MAC videolaryngoscope exceptionally useful for emergency intubation. In addition, the C-MAC videolaryngoscope is a very good tool for tracheal intubation teaching. However, tracheal intubation with C-MAC videolaryngoscope may occasionally fail and introduction of C-MAC videolaryngoscope in clinical practice must be accompanied by formal training programs in normal and difficult airway managements. PMID:28740393

Effect of fentanyl and lidocaine on the end-tidal sevoflurane concentration preventing motor movement in dogs.

PubMed

Suarez, Martin A; Seddighi, Reza; Egger, Christine M; Rohrbach, Barton W; Cox, Sherry K; KuKanich, Butch K; Doherty, Thomas J

2017-01-01

OBJECTIVE To determine effects of fentanyl, lidocaine, and a fentanyl-lidocaine combination on the minimum alveolar concentration of sevoflurane preventing motor movement (MAC NM ) in dogs. ANIMALS 6 adult Beagles. PROCEDURES Dogs were anesthetized with sevoflurane in oxygen 3 times (1-week intervals). Baseline MAC NM (MAC NM-B ) was determined starting 45 minutes after induction of anesthesia. Dogs then received 1 of 3 treatments IV: fentanyl (loading dose, 15 μg/kg; constant rate infusion [CRI], 6 μg/kg/h), lidocaine (loading dose, 2 mg/kg; CRI, 6 mg/kg/h), and the fentanyl-lidocaine combination at the same doses. Determination of treatment MAC NM (MAC NM-T ) was initiated 90 minutes after start of the CRI. Venous blood samples were collected at the time of each treatment MAC NM measurement for determination of plasma concentrations of fentanyl and lidocaine. RESULTS Mean ± SEM overall MAC NM-B for the 3 treatments was 2.70 ± 0.27 vol%. The MAC NM decreased from MAC NM-B to MAC NM-T by 39%, 21%, and 55% for fentanyl, lidocaine, and the fentanyl-lidocaine combination, respectively. This decrease differed significantly among treatments. Plasma fentanyl concentration was 3.25 and 2.94 ng/mL for fentanyl and the fentanyl-lidocaine combination, respectively. Plasma lidocaine concentration was 2,570 and 2,417 ng/mL for lidocaine and the fentanyl-lidocaine combination, respectively. Plasma fentanyl and lidocaine concentrations did not differ significantly between fentanyl and the fentanyl-lidocaine combination or between lidocaine and the fentanyl-lidocaine combination. CONCLUSIONS AND CLINICAL RELEVANCE CRIs of fentanyl, lidocaine, and the fentanyl-lidocaine combination at the doses used were associated with clinically important and significant decreases in the MAC NM of sevoflurane in dogs.

Awake Craniotomy Anesthesia: A Comparison of the Monitored Anesthesia Care and Asleep-Awake-Asleep Techniques.

PubMed

Eseonu, Chikezie I; ReFaey, Karim; Garcia, Oscar; John, Amballur; Quiñones-Hinojosa, Alfredo; Tripathi, Punita

2017-08-01

Commonly used sedation techniques for an awake craniotomy include monitored anesthesia care (MAC), using an unprotected airway, and the asleep-awake-asleep (AAA) technique, using a partially or totally protected airway. We present a comparative analysis of the MAC and AAA techniques, evaluating anesthetic management, perioperative outcomes, and complications in a consecutive series of patients undergoing the removal of an eloquent brain lesion. Eighty-one patients underwent awake craniotomy for an intracranial lesion over a 9-year period performed by a single-surgeon and a team of anesthesiologists. Fifty patients were treated using the MAC technique, and 31 were treated using the AAA technique. A retrospective analysis evaluated anesthetic management, intraoperative complications, postoperative outcomes, pain management, and complications. The MAC and AAA groups had similar preoperative patient and tumor characteristics. Mean operative time was shorter in the MAC group (283.5 minutes vs. 313.3 minutes; P = 0.038). Hypertension was the most common intraoperative complication seen (8% in the MAC group vs. 9.7% in the AAA group; P = 0.794). Intraoperative seizure occurred at a rate of 4% in the MAC group and 3.2% in the AAA group (P = 0.858). Awake cases were converted to general anesthesia in no patients in the MAC group and in 1 patient (3.2%) in the AAA group (P = 0.201). No cases were aborted in either group. The mean hospital length of stay was 3.98 days in the MAC group and 3.84 days in the AAA group (P = 0.833). Both the MAC and AAA sedation techniques provide an efficacious and safe method for managing awake craniotomy cases and produce similar perioperative outcomes, with the MAC technique associated with shorter operative time. Copyright © 2017 Elsevier Inc. All rights reserved.

Efficient removal of amoxicillin and paracetamol from aqueous solutions using magnetic activated carbon.

PubMed

Saucier, Caroline; Karthickeyan, P; Ranjithkumar, V; Lima, Eder C; Dos Reis, Glaydson S; de Brum, Irineu A S

2017-02-01

Activated carbon (AC)/CoFe 2 O 4 nanocomposites, MAC-1 and MAC-2, were prepared by a simple pyrolytic method using a mixture of iron(III)/cobalt(II) benzoates and iron(III)/cobalt(II) oxalates, respectively, and were used as efficient adsorbents for the removal of amoxicillin (AMX) and paracetamol (PCT) of aqueous effluents. The synthesized nanocomposites were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), vibrating sample magnetometry (VSM), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and transmission electron microscopy (TEM). The sizes of cobalt ferrite nanoparticles formed from benzoates of iron(III)/cobalt(II) and oxalates of iron(III)/cobalt(II) precursors were in the ranges of 5-80 and 6-27 nm, respectively. The saturation magnetization (M s ), remanence (M r ) and coercivity (H c ) of the MAC-2 nanocomposites were found to be 3.07 emu g -1 , 1.36 emu g -1 and 762.49 Oe; for MAC-1, they were 0.2989 emu g -1 , 0.0466 emu g -1 and 456.82 Oe. The adsorption kinetics and isotherm studies were investigated, and the results showed that the as-prepared nanocomposites MAC-1 and MAC-2 could be utilized as an efficient, magnetically separable adsorbent for environmental cleanup. The maximum sorption capacities obtained were 280.9 and 444.2 mg g -1 of AMX for MAC-1 and MAC-2, respectively, and 215.1 and 399.9 mg g -1 of PCT using MAC-1 and MAC-2, respectively. Both adsorbents were successfully used for simulated hospital effluents, removing at least 93.00 and 96.77% for MAC-1 and MAC-2, respectively, of a mixture of nine pharmaceuticals with high concentrations of sugars, organic components and saline concentrations.

Refractory inclusions from the ungrouped carbonaceous chondrites MAC 87300 and MAC 88107

NASA Astrophysics Data System (ADS)

Russell, Sara S.; Davis, Andrew M.; MacPherson, Glenn J.; Guan, Yunbin; Huss, Gary R.

2000-09-01

MAC 87300 and MAC 88107 are two unusual carbonaceous chondrites that are intermediate in chemical composition between the CO3 and CM2 meteorite groups. Calcium-aluminum-rich inclusions (CAIs) from these two meteorites are mostly spinel-pyroxene and melilite-rich (Type A) varieties. Spinel-pyroxene inclusions have either a banded or nodular texture, with aluminous diopside rimming iron-poor spinel. Melilite-rich inclusions (4-42) are irregular in shape and contain minor spinel (FeO <1 wt%), perovskite and, more rarely, hibonite. The CAIs in MAC 88107 and MAC 87300 are similar in primary mineralogy to CAIs from low petrologic grade CO3 meteorites, but differ in that they commonly contain phyllosilicates. The two meteorites also differ somewhat from each other: melilite is more abundant and slightly more aluminum-rich in inclusions from MAC 88107 than in those from MAC 87300, and phyllosilicate is more abundant and magnesium-poor in MAC 87300 CAIs relative to that in MAC 88107. These differences suggest that the two meteorites are not paired. CAI sizes and the abundance of melilite-rich CAIs in MAC 88107 and MAC 87300 suggests a genetic relationship to CO3 meteorites, but the CAIs in both have suffered a greater degree of aqueous alteration than is observed in COs. Al-rich melilite in CAIs from both meteorites generally contains excess 26Mg, presumably from the in situ decay of 26Al. Although well-defined isochrons are not observed, the 26Mg excesses are consistent with initial 26Al/27Al ~3-5 ( 10-5. An unusual hibonite-bearing inclusion is isotopically heterogeneous, with two large and abutting hibonite crystals showing significant differences in their degrees of mass-dependent fractionation of 25Mg/24Mg. The two crystals also show differences in their inferred initial 26Al/27Al, 1 ( 10-5 vs. 3 ( 10-6.

De novo formed satellite DNA-based mammalian artificial chromosomes and their possible applications.

PubMed

Katona, Robert L

2015-02-01

Mammalian artificial chromosomes (MACs) are non-integrating, autonomously replicating natural chromosome-based vectors that may carry a vast amount of genetic material, which in turn enable potentially prolonged, safe, and regulated therapeutic transgene expression and render MACs as attractive genetic vectors for "gene replacement" or for controlling differentiation pathways in target cells. Satellite-DNA-based artificial chromosomes (SATACs) can be made by induced de novo chromosome formation in cells of different mammalian and plant species. These artificially generated accessory chromosomes are composed of predictable DNA sequences, and they contain defined genetic information. SATACs have already passed a number of obstacles crucial to their further development as gene therapy vectors, including large-scale purification, transfer of purified artificial chromosomes into different cells and embryos, generation of transgenic animals and germline transmission with purified SATACs, and the tissue-specific expression of a therapeutic gene from an artificial chromosome in the milk of transgenic animals. SATACs could be used in cell therapy protocols. For these methods, the most versatile target cell would be one that was pluripotent and self-renewing to address multiple disease target cell types, thus making multilineage stem cells, such as adult derived early progenitor cells and embryonic stem cells, as attractive universal host cells.

Frame Transmission Efficiency-Based Cross-Layer Congestion Notification Scheme in Wireless Ad Hoc Networks.

PubMed

He, Huaguang; Li, Taoshen; Feng, Luting; Ye, Jin

2017-07-15

Different from the traditional wired network, the fundamental cause of transmission congestion in wireless ad hoc networks is medium contention. How to utilize the congestion state from the MAC (Media Access Control) layer to adjust the transmission rate is core work for transport protocol design. However, recent works have shown that the existing cross-layer congestion detection solutions are too complex to be deployed or not able to characterize the congestion accurately. We first propose a new congestion metric called frame transmission efficiency (i.e., the ratio of successful transmission delay to the frame service delay), which describes the medium contention in a fast and accurate manner. We further present the design and implementation of RECN (ECN and the ratio of successful transmission delay to the frame service delay in the MAC layer, namely, the frame transmission efficiency), a general supporting scheme that adjusts the transport sending rate through a standard ECN (Explicit Congestion Notification) signaling method. Our method can be deployed on commodity switches with small firmware updates, while making no modification on end hosts. We integrate RECN transparently (i.e., without modification) with TCP on NS2 simulation. The experimental results show that RECN remarkably improves network goodput across multiple concurrent TCP flows.

Characterizing Design Cognition of High School Students: Initial Analyses Comparing Those with and without Pre-Engineering Experiences

ERIC Educational Resources Information Center

Wells, John; Lammi, Matthew; Gero, John; Grubbs, Michael E.; Paretti, Marie; Williams, Christopher

2016-01-01

Reported in this article are initial results from of a longitudinal study to characterize the design cognition and cognitive design styles of high school students with and without pre-engineering course experience over a 2-year period, and to compare them with undergraduate engineering students. The research followed a verbal protocol analysis…

EEG-Neurofeedback as a Tool to Modulate Cognition and Behavior: A Review Tutorial

PubMed Central

Enriquez-Geppert, Stefanie; Huster, René J.; Herrmann, Christoph S.

2017-01-01

Neurofeedback is attracting renewed interest as a method to self-regulate one’s own brain activity to directly alter the underlying neural mechanisms of cognition and behavior. It not only promises new avenues as a method for cognitive enhancement in healthy subjects, but also as a therapeutic tool. In the current article, we present a review tutorial discussing key aspects relevant to the development of electroencephalography (EEG) neurofeedback studies. In addition, the putative mechanisms underlying neurofeedback learning are considered. We highlight both aspects relevant for the practical application of neurofeedback as well as rather theoretical considerations related to the development of new generation protocols. Important characteristics regarding the set-up of a neurofeedback protocol are outlined in a step-by-step way. All these practical and theoretical considerations are illustrated based on a protocol and results of a frontal-midline theta up-regulation training for the improvement of executive functions. Not least, assessment criteria for the validation of neurofeedback studies as well as general guidelines for the evaluation of training efficacy are discussed. PMID:28275344

Receiver Statistics for Cognitive Radios in Dynamic Spectrum Access Networks

DTIC Science & Technology

2012-02-28

SNR) are employed by many protocols and processes in direct-sequence ( DS ) spread-spectrum packet radio networks, including soft-decision decoding...adaptive modulation protocols, and power adjustment protocols. For DS spread spectrum, we have introduced and evaluated SNR estimators that employ...obtained during demodulation in a binary CDMA receiver. We investigated several methods to apply the proposed metric to the demodulator’s soft-decision

Photocopy of drawing (original drawing of MacDill Field in possession ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Photocopy of drawing (original drawing of MacDill Field in possession of MacDill Air Force Base, Civil Engineering, Tampa, Florida; site plan dated December, 1942) BASE LAYOUT, DECEMBER 1942 - MacDill Air Force Base, Bounded by City of Tampa North, Tampa Bay South, Old Tampa Bay West, & Hillsborough Bay East, Tampa, Hillsborough County, FL

Generic Drug Cost Containment in Medicaid: Lessons from Five State MAC Programs

PubMed Central

Abramson, Richard G.; Harrington, Catherine A.; Missmar, Raad; Li, Susan P.; Mendelson, Daniel N.

2004-01-01

In Medicaid, generic drug cost containment revolves around two programs: the Federal upper limit (FUL) program and State maximum allowable cost (MAC) programs. This article analyzes MAC programs in five States and finds considerable variation between these programs and the FUL program in both size and pricing aggressiveness. We conclude that expansion of existing MAC programs and creation of new ones could contribute to cost containment efforts nationwide. Options for States seeking to optimize their efforts include focusing on pricing for drugs with high sales volumes, ensuring that MAC lists include prices for all forms and dosages of listed drug entities, and collaborating with other States or the Federal Government on MAC list operations. PMID:15229994

Effects of carprofen and morphine on the minimum alveolar concentration of isoflurane in dogs.

PubMed

Ko, Jeff C H; Weil, Ann B; Inoue, Tomohito

2009-01-01

The minimum alveolar concentration (MAC) of isoflurane in dogs was determined following carprofen (2.2 mg/kg per os) alone, morphine (1 mg/kg intravenously) alone, carprofen and morphine, and no drug control in eight healthy adult dogs. Isoflurane MAC following administration of morphine alone (0.81%+/-0.18%) or carprofen and morphine (0.68%+/-0.31%) was significantly less than the control MAC (1.24%+/-0.15%). Isoflurane MAC after carprofen alone (1.13%+/-0.13%) was not significantly different from the control value. Results indicated that administration of morphine alone or in combination with carprofen significantly reduced the MAC of isoflurane in dogs. The isoflurane MAC reduction was additive between the effects of carprofen and morphine.

Development of Thread-compatible Open Source Stack

NASA Astrophysics Data System (ADS)

Zimmermann, Lukas; Mars, Nidhal; Schappacher, Manuel; Sikora, Axel

2017-07-01

The Thread protocol is a recent development based on 6LoWPAN (IPv6 over IEEE 802.15.4), but with extensions regarding a more media independent approach, which - additionally - also promises true interoperability. To evaluate and analyse the operation of a Thread network a given open source 6LoWPAN stack for embedded devices (emb::6) has been extended in order to comply with the Thread specification. The implementation covers Mesh Link Establishment (MLE) and network layer functionality as well as 6LoWPAN mesh under routing mechanism based on MAC short addresses. The development has been verified on a virtualization platform and allows dynamical establishment of network topologies based on Thread’s partitioning algorithm.

The aging physician and surgeon.

PubMed

Sataloff, Robert T; Hawkshaw, Mary; Kutinsky, Joshua; Maitz, Edward A

2016-01-01

As the population of aging physicians increases, methods of assessing physicians' cognitive function and predicting clinically significant changes in clinical performance become increasingly important. Although several approaches have been suggested, no evaluation system is accepted or utilized widely. This article reviews literature using MEDLINE, PubMed, and other sources. Articles discussing the problems of geriatric physicians are summarized, stressing publications that proposed methods of evaluation. Selected literature on evaluating aging pilots also was reviewed, and potential applications for physician evaluation are proposed. Neuropsychological cognitive test protocols were summarized, and a reduced evaluation protocol is proposed for interdisciplinary longitudinal research. Although there are several articles evaluating cognitive function in aging physicians and aging pilots, and although a few institutions have instituted cognitive evaluation, there are no longitudinal data assessing cognitive function in physicians over time or correlating them with performance. Valid, reliable testing of cognitive function of physicians is needed. In order to understand its predictive value, physicians should be tested over time starting when they are young, and results should be correlated with physician performance. Early testing is needed to determine whether cognitive deficits are age-related or long-standing. A multi-institutional study over many years is proposed. Additional assessments of other factors such as manual dexterity (perhaps using simulators) and physician frailty are recommended.

An Energy-Efficient and Robust Multipath Routing Protocol for Cognitive Radio Ad Hoc Networks.

PubMed

Singh, Kishor; Moh, Sangman

2017-09-04

Routing in cognitive radio ad hoc networks (CRAHNs) is a daunting task owing to dynamic topology, intermittent connectivity, spectrum heterogeneity, and energy constraints. Other prominent aspects such as channel stability, path reliability, and route discovery frequency should also be exploited. Several routing protocols have been proposed for CRAHNs in the literature. By stressing on one of the aspects more than any other, however, they do not satisfy all requirements of throughput, energy efficiency, and robustness. In this paper, we propose an energy-efficient and robust multipath routing (ERMR) protocol for CRAHNs by considering all prominent aspects including residual energy and channel stability in design. Even when the current routing path fails, the alternative routing path is immediately utilized. In establishing primary and alternative routing paths, both residual energy and channel stability are exploited simultaneously. Our simulation study shows that the proposed ERMR outperforms the conventional protocol in terms of network throughput, packet delivery ratio, energy consumption, and end-to-end delay.

An Energy-Efficient and Robust Multipath Routing Protocol for Cognitive Radio Ad Hoc Networks

PubMed Central

Singh, Kishor

2017-01-01

Routing in cognitive radio ad hoc networks (CRAHNs) is a daunting task owing to dynamic topology, intermittent connectivity, spectrum heterogeneity, and energy constraints. Other prominent aspects such as channel stability, path reliability, and route discovery frequency should also be exploited. Several routing protocols have been proposed for CRAHNs in the literature. By stressing on one of the aspects more than any other, however, they do not satisfy all requirements of throughput, energy efficiency, and robustness. In this paper, we propose an energy-efficient and robust multipath routing (ERMR) protocol for CRAHNs by considering all prominent aspects including residual energy and channel stability in design. Even when the current routing path fails, the alternative routing path is immediately utilized. In establishing primary and alternative routing paths, both residual energy and channel stability are exploited simultaneously. Our simulation study shows that the proposed ERMR outperforms the conventional protocol in terms of network throughput, packet delivery ratio, energy consumption, and end-to-end delay. PMID:28869551

Effects of butorphanol and carprofen on the minimal alveolar concentration of isoflurane in dogs.

PubMed

Ko, J C; Lange, D N; Mandsager, R E; Payton, M E; Bowen, C; Kamata, A; Kuo, W C

2000-10-01

To evaluate the effects of butorphanol and carprofen, alone and in combination, on the minimal alveolar concentration (MAC) of isoflurane in dogs. Randomized complete-block crossover study. 6 healthy adult dogs. Minimal alveolar concentration of isoflurane was determined following administration of carprofen alone, butorphanol alone, carprofen and butorphanol, and neither drug (control). Anesthesia was induced with isoflurane in oxygen, and MAC was determined by use of a tail clamp method. Three hours prior to induction of anesthesia, dogs were fed a small amount of canned food without any drugs (control) or with carprofen (2.2 mg/kg of body weight [1 mg/lb]). Following initial determination of MAC, butorphanol (0.4 mg/kg [0.18 mg/lb], i.v.) was administered, and MAC was determined again. Heart rate, respiratory rate, indirect arterial blood pressure, endtidal partial pressure of CO2, and saturation of hemoglobin with oxygen were recorded at the time MAC was determined. Mean +/- SD MAC of isoflurane following administration of butorphanol alone (1.03 +/- 0.22%) or carprofen and butorphanol (0.90 +/- 0.21%) were significantly less than the control MAC (1.28 +/- 0.14%), but MAC after administration of carprofen alone (1.20 +/- 0.13%) was not significantly different from the control value. The effects of carprofen and butorphanol on the MAC of isoflurane were additive. There were not any significant differences among treatments in regard to cardiorespiratory data. Results suggest that administration of butorphanol alone or in combination with carprofen significantly reduces the MAC of isoflurane in dogs; however, the effects of butorphanol and carprofen are additive, not synergistic.

Suppression of c-Myc induces apoptosis via an AMPK/mTOR-dependent pathway by 4-O-methyl-ascochlorin in leukemia cells.

PubMed

Shin, Jae-Moon; Jeong, Yun-Jeong; Cho, Hyun-Ji; Magae, Junji; Bae, Young-Seuk; Chang, Young-Chae

2016-05-01

4-O-Methyl-ascochlorin (MAC) is a methylated derivative of the prenyl-phenol antibiotic ascochlorin, which was isolated from an incomplete fungus, Ascochyta viciae. Although the effects of MAC on apoptosis have been reported, the underlying mechanisms remain unknown. Here, we show that MAC promoted apoptotic cell death and downregulated c-Myc expression in K562 human leukemia cells. The effect of MAC on apoptosis was similar to that of 10058-F4 (a c-Myc inhibitor) or c-Myc siRNA, suggesting that the downregulation of c-Myc expression plays a role in the apoptotic effect of MAC. Further investigation showed that MAC downregulated c-Myc by inhibiting protein synthesis. MAC promoted the phosphorylation of AMP-activated protein kinase (AMPK) and inhibited the phosphorylation of mammalian target of rapamycin (mTOR) and its target proteins, including p70S6 K and 4E-BP-1. Treatment of cells with AICAR (an AMPK activator), rapamycin (an mTOR inhibitor), or mTOR siRNA downregulated c-Myc expression and induced apoptosis to a similar extent to that of MAC. These results suggest that the effect of MAC on apoptosis induction in human leukemia cells is mediated by the suppression of c-Myc protein synthesis via an AMPK/mTOR-dependent mechanism.

Continuous infusion of low-dose unfractionated heparin after aneurysmal subarachnoid hemorrhage: a preliminary study of cognitive outcomes.

PubMed

James, Robert F; Khattar, Nicolas K; Aljuboori, Zaid S; Page, Paul S; Shao, Elaine Y; Carter, Lacey M; Meyer, Kimberly S; Daniels, Michael W; Craycroft, John; Gaughen, John R; Chaudry, M Imran; Rai, Shesh N; Everhart, D Erik; Simard, J Marc

2018-05-11

OBJECTIVE Cognitive dysfunction occurs in up to 70% of aneurysmal subarachnoid hemorrhage (aSAH) survivors. Low-dose intravenous heparin (LDIVH) infusion using the Maryland protocol was recently shown to reduce clinical vasospasm and vasospasm-related infarction. In this study, the Montreal Cognitive Assessment (MoCA) was used to evaluate cognitive changes in aSAH patients treated with the Maryland LDIVH protocol compared with controls. METHODS A retrospective analysis of all patients treated for aSAH between July 2009 and April 2014 was conducted. Beginning in 2012, aSAH patients were treated with LDIVH in the postprocedural period. The MoCA was administered to all aSAH survivors prospectively during routine follow-up visits, at least 3 months after aSAH, by trained staff blinded to treatment status. Mean MoCA scores were compared between groups, and regression analyses were performed for relevant factors. RESULTS No significant differences in baseline characteristics were observed between groups. The mean MoCA score for the LDIVH group (n = 25) was 26.4 compared with 22.7 in controls (n = 22) (p = 0.013). Serious cognitive impairment (MoCA ≤ 20) was observed in 32% of controls compared with 0% in the LDIVH group (p = 0.008). Linear regression analysis demonstrated that only LDIVH was associated with a positive influence on MoCA scores (β = 3.68, p =0.019), whereas anterior communicating artery aneurysms and fevers were negatively associated with MoCA scores. Multivariable linear regression analysis resulted in all 3 factors maintaining significance. There were no treatment complications. CONCLUSIONS This preliminary study suggests that the Maryland LDIVH protocol may improve cognitive outcomes in aSAH patients. A randomized controlled trial is needed to determine the safety and potential benefit of unfractionated heparin in aSAH patients.

Evaluating a Website to Teach Children Safety with Dogs: A Randomized Controlled Trial

PubMed Central

Schwebel, David C.; Li, Peng; McClure, Leslie A.; Severson, Joan

2016-01-01

Dog bites represent a significant threat to child health. Theory-driven interventions scalable for broad dissemination are sparse. A website was developed to teach children dog safety via increased knowledge, improved cognitive skills in relevant domains, and increased perception of vulnerability to bites. A randomized controlled trial was conducted with 69 children aged 4–5 randomly assigned to use the dog safety website or a control transportation safety website for ~3 weeks. Assessment of dog safety knowledge and behavior plus skill in three relevant cognitive constructs (impulse control, noticing details, and perspective-taking) was conducted both at baseline and following website use. The dog safety website incorporated interactive games, instructional videos including testimonials, a motivational rewards system, and messaging to parents concerning child lessons. Our results showed that about two-thirds of the intervention sample was not adherent to website use at home, so both intent-to-treat and per-protocol analyses were conducted. Intent-to-treat analyses yielded mostly null results. Per-protocol analyses suggested children compliant to the intervention protocol scored higher on knowledge and recognition of safe behavior with dogs following the intervention compared to the control group. Adherent children also had improved scores post-intervention on the cognitive skill of noticing details compared to the control group. We concluded that young children’s immature cognition can lead to dog bites. Interactive eHealth training on websites shows potential to teach children relevant cognitive and safety skills to reduce risk. Compliance to website use is a challenge, and some relevant cognitive skills (e.g., noticing details) may be more amenable to computer-based training than others (e.g., impulse control). PMID:27918466

Evaluating a Website to Teach Children Safety with Dogs: A Randomized Controlled Trial.

PubMed

Schwebel, David C; Li, Peng; McClure, Leslie A; Severson, Joan

2016-12-02

Dog bites represent a significant threat to child health. Theory-driven interventions scalable for broad dissemination are sparse. A website was developed to teach children dog safety via increased knowledge, improved cognitive skills in relevant domains, and increased perception of vulnerability to bites. A randomized controlled trial was conducted with 69 children aged 4-5 randomly assigned to use the dog safety website or a control transportation safety website for ~3 weeks. Assessment of dog safety knowledge and behavior plus skill in three relevant cognitive constructs (impulse control, noticing details, and perspective-taking) was conducted both at baseline and following website use. The dog safety website incorporated interactive games, instructional videos including testimonials, a motivational rewards system, and messaging to parents concerning child lessons. Our results showed that about two-thirds of the intervention sample was not adherent to website use at home, so both intent-to-treat and per-protocol analyses were conducted. Intent-to-treat analyses yielded mostly null results. Per-protocol analyses suggested children compliant to the intervention protocol scored higher on knowledge and recognition of safe behavior with dogs following the intervention compared to the control group. Adherent children also had improved scores post-intervention on the cognitive skill of noticing details compared to the control group. We concluded that young children's immature cognition can lead to dog bites. Interactive eHealth training on websites shows potential to teach children relevant cognitive and safety skills to reduce risk. Compliance to website use is a challenge, and some relevant cognitive skills (e.g., noticing details) may be more amenable to computer-based training than others (e.g., impulse control).

THE ISOLATION AND IDENTIFICATION OF MYCOBACTERIUM AVIUM COMPLEX (MAC) RECOVERED FROM LOS ANGELES POTABLE WATER, A POSSIBLE SOURCE OF INFECTION IN AIDS PATIENTS

EPA Science Inventory

Los Angeles water was investigated as a possible source of Mycobacterium avium complex (MAC) infection in patients with AIDS. MAC consists of M.avium (MA), M. intracellulare (MI) and Mycobacterium X (MX)(positive for MAC by DNA probe but not MA or MI). The study included 13 reser...

33 CFR 165.768 - Security Zone; MacDill Air Force Base, Tampa Bay, FL.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Security Zone; MacDill Air Force....768 Security Zone; MacDill Air Force Base, Tampa Bay, FL. (a) Location. The following area is a... title. All waters within Tampa Bay, Florida in the vicinity of MacDill Air Force Base, including...

Introduction to MacDraft. High-Technology Training Module.

ERIC Educational Resources Information Center

Traxler, Gene

This training module on MacDraft is part of a computer drafting skills unit on communications technology for grades 9-12. The objective is for each student to complete a drawing on the MacIntosh computer using the MacDraft software program. This drawing is to be dimensioned with a dual system and is to include a border and title block. This module…

Antibiotic Resistance Mediated by the MacB ABC Transporter Family: A Structural and Functional Perspective

PubMed Central

Greene, Nicholas P.; Kaplan, Elise; Crow, Allister; Koronakis, Vassilis

2018-01-01

The MacB ABC transporter forms a tripartite efflux pump with the MacA adaptor protein and TolC outer membrane exit duct to expel antibiotics and export virulence factors from Gram-negative bacteria. Here, we review recent structural and functional data on MacB and its homologs. MacB has a fold that is distinct from other structurally characterized ABC transporters and uses a unique molecular mechanism termed mechanotransmission. Unlike other bacterial ABC transporters, MacB does not transport substrates across the inner membrane in which it is based, but instead couples cytoplasmic ATP hydrolysis with transmembrane conformational changes that are used to perform work in the extra-cytoplasmic space. In the MacAB-TolC tripartite pump, mechanotransmission drives efflux of antibiotics and export of a protein toxin from the periplasmic space via the TolC exit duct. Homologous tripartite systems from pathogenic bacteria similarly export protein-like signaling molecules, virulence factors and siderophores. In addition, many MacB-like ABC transporters do not form tripartite pumps, but instead operate in diverse cellular processes including antibiotic sensing, cell division and lipoprotein trafficking. PMID:29892271

Serrated adenocarcinoma morphology in colorectal mucinous adenocarcinoma is associated with improved patient survival

PubMed Central

Lee, Chung-Ta; Chow, Nan-Haw; Su, Pei-Fang; Ho, Chung-Liang; Tsai, Hung-Wen; Chen, Yi-Lin; Lin, Shao-Chieh; Lin, Bo-Wen; Lin, Peng-Chan; Lee, Jenq-Chang

2017-01-01

Colorectal mucinous adenocarcinoma (MAC) and serrated adenocarcinoma (SAC) share many characteristics, including right-side colon location, frequent mucin production, and various molecular features. This study examined the frequency of SAC morphology in MACs. We assessed the correlation of SAC morphology with clinicopathological parameters, molecular characteristics, and patient prognosis. Eighty-eight colorectal MACs were collected and reviewed for SAC morphology according to Makinen's criteria. We sequenced KRAS and BRAF, assessed CpG island methylator phenotype (CIMP) frequency, and analyzed DNA mismatch repair enzyme levels using immunohistochemistry in tumor samples. SAC morphology was observed in 38% of MACs, and was associated with proximal location (P=0.001), BRAF mutation (P=0.042), CIMP-positive status (P=0.023), and contiguous traditional serrated adenoma (P=0.019). Multivariate analysis revealed that MACs without both SAC morphology and CIMP-positive status exhibited 3.955 times greater risk of cancer relapse than MACs having both characteristics or either one (P=0.035). Our results show that two MAC groups with distinct features can be identified using Makinen's criteria, and suggest a favorable prognostic role for the serrated neoplastic pathway in colorectal MAC. PMID:28422723

Considerations for Improving the Capacity and Performance of AeroMACS

NASA Technical Reports Server (NTRS)

Kerczewski, Robert J.; Kamali, Behnam; Apaza, Rafael D.; Wilson, Jeffrey D.; Dimond, Robert P.

2014-01-01

The Aeronautical Mobile Airport Communications System (AeroMACS) has progressed from concept through prototype development, testing, and standards development and is now poised for the first operational deployments at nine US airports by the Federal Aviation Administration. These initial deployments will support fixed applications. Mobile applications providing connectivity to and from aircraft and ground-based vehicles on the airport surface will occur at some point in the future. Given that many fixed applications are possible for AeroMACS, it is necessary to now consider whether the existing capacity of AeroMACS will be reached even before the mobile applications are ready to be added, since AeroMACS is constrained by both available bandwidth and transmit power limitations. This paper describes some concepts that may be applied to improve the future capacity of AeroMACS, with a particular emphasis on gains that can be derived from the addition of IEEE 802.16j multihop relays to the AeroMACS standard, where a significant analysis effort has been undertaken.

Interference Analysis Status and Plans for Aeronautical Mobile Airport Communications System (AeroMACS)

NASA Technical Reports Server (NTRS)

Kerczewski, Robert J.; Wilson, Jeffrey D.

2010-01-01

Interference issues related to the operation of an aeronautical mobile airport communications system (AeroMACS) in the C-Band (specifically 5091-5150 MHz) is being investigated. The issue of primary interest is co-channel interference from AeroMACS into mobile-satellite system (MSS) feeder uplinks. The effort is focusing on establishing practical limits on AeroMACS transmissions from airports so that the threshold of interference into MSS is not exceeded. The analyses are being performed with the software package Visualyse Professional, developed by Transfinite Systems Limited. Results with omni-directional antennas and plans to extend the models to represent AeroMACS more accurately will be presented. These models should enable realistic analyses of emerging AeroMACS designs to be developed from NASA Test Bed, RTCA 223, and European results.

Cardiac macrophages adopt profibrotic/M2 phenotype in infarcted hearts: Role of urokinase plasminogen activator.

PubMed

Carlson, Signe; Helterline, Deri; Asbe, Laura; Dupras, Sarah; Minami, Elina; Farris, Stephen; Stempien-Otero, April

2017-07-01

Macrophages (mac) that over-express urokinase plasminogen activator (uPA) adopt a profibrotic M2 phenotype in the heart in association with cardiac fibrosis. We tested the hypothesis that cardiac macs are M2 polarized in infarcted mouse and human hearts and that polarization is dependent on mac-derived uPA. Studies were performed using uninjured (UI) or infarcted (MI) hearts of uPA overexpressing (SR-uPA), uPA null, or nontransgenic littermate (Ntg) mice. At 7days post-infarction, cardiac mac were isolated, RNA extracted and M2 markers Arg1, YM1, and Fizz1 measured with qrtPCR. Histologic analysis for cardiac fibrosis, mac and myofibroblasts was performed at the same time-point. Cardiac macs were also isolated from Ntg hearts and RNA collected after primary isolation or culture with vehicle, IL-4 or plasmin and M2 marker expression measured. Cardiac tissue and blood was collected from humans with ischemic heart disease. Expression of M2 marker CD206 and M1 marker TNFalpha was measured. Macs from WT mice had increased expression of Arg1 and Ym1 following MI (41.3±6.5 and 70.3±36, fold change vs UI, n=8, P<0.007). There was significant up-regulation of cardiac mac Arg1 and YM1 with MI in both WT and uPA null mice (n=4-9 per genotype and condition). Treatment with plasmin increased expression of Arg1 and YM1 in cultured cardiac macs. Histologic analysis revealed increased density of activated fibroblasts and M2 macs in SR-uPA hearts post-infarction with associated increases in fibrosis. Cardiac macs isolated from human hearts with ischemic heart disease expressed increased levels of the M2 marker CD206 in comparison to blood-derived macs (4.9±1.3). Cardiac macs in mouse and human hearts adopt a M2 phenotype in association with fibrosis. Plasmin can induce an M2 phenotype in cardiac macs. However, M2 activation can occur in the heart in vivo in the absence of uPA indicating that alternative pathways to activate plasmin are present in the heart. Excess uPA promotes increased fibroblast density potentially via potentiating fibroblast migration or proliferation. Altering macrophage phenotype in the heart is a potential target to modify cardiac fibrosis. Copyright © 2016 Elsevier Ltd. All rights reserved.

A Randomized Clinical Trial to Dismantle Components of Cognitive Processing Therapy for Posttraumatic Stress Disorder in Female Victims of Interpersonal Violence

ERIC Educational Resources Information Center

Resick, Patricia A.; Galovski, Tara E.; Uhlmansiek, Mary O'Brien; Scher, Christine D.; Clum, Gretchen A.; Young-Xu, Yinong

2008-01-01

The purpose of this experiment was to conduct a dismantling study of cognitive processing therapy in which the full protocol was compared with its constituent components--cognitive therapy only (CPT-C) and written accounts (WA)--for the treatment of posttraumatic stress disorder (PTSD) and comorbid symptoms. The intent-to-treat (ITT) sample…

Isolation and characterisation of human gingival margin-derived STRO-1/MACS+ and MACS− cell populations

PubMed Central

El-Sayed, Karim M Fawzy; Paris, Sebastian; Graetz, Christian; Kassem, Neemat; Mekhemar, Mohamed; Ungefroren, Hendrick; Fändrich, Fred; Dörfer, Christof

2015-01-01

Recently, gingival margin-derived stem/progenitor cells isolated via STRO-1/magnetic activated cell sorting (MACS) showed remarkable periodontal regenerative potential in vivo. As a second-stage investigation, the present study's aim was to perform in vitro characterisation and comparison of the stem/progenitor cell characteristics of sorted STRO-1-positive (MACS+) and STRO-1-negative (MACS−) cell populations from the human free gingival margin. Cells were isolated from the free gingiva using a minimally invasive technique and were magnetically sorted using anti-STRO-1 antibodies. Subsequently, the MACS+ and MACS− cell fractions were characterized by flow cytometry for expression of CD14, CD34, CD45, CD73, CD90, CD105, CD146/MUC18 and STRO-1. Colony-forming unit (CFU) and multilineage differentiation potential were assayed for both cell fractions. Mineralisation marker expression was examined using real-time polymerase chain reaction (PCR). MACS+ and MACS− cell fractions showed plastic adherence. MACS+ cells, in contrast to MACS− cells, showed all of the predefined mesenchymal stem/progenitor cell characteristics and a significantly higher number of CFUs (P<0.01). More than 95% of MACS+ cells expressed CD105, CD90 and CD73; lacked the haematopoietic markers CD45, CD34 and CD14, and expressed STRO-1 and CD146/MUC18. MACS− cells showed a different surface marker expression profile, with almost no expression of CD14 or STRO-1, and more than 95% of these cells expressed CD73, CD90 and CD146/MUC18, as well as the haematopoietic markers CD34 and CD45 and CD105. MACS+ cells could be differentiated along osteoblastic, adipocytic and chondroblastic lineages. In contrast, MACS− cells demonstrated slight osteogenic potential. Unstimulated MACS+ cells showed significantly higher expression of collagen I (P<0.05) and collagen III (P<0.01), whereas MACS− cells demonstrated higher expression of osteonectin (P<0.05; Mann–Whitney). The present study is the first to compare gingival MACS+ and MACS− cell populations demonstrating that MACS+ cells, in contrast to MACS− cells, harbour stem/progenitor cell characteristics. This study also validates the effectiveness of the STRO-1/MACS+ technique for the isolation of gingival stem/progenitor cells. Human free gingival margin-derived STRO-1/MACS+ cells are a unique renewable source of multipotent stem/progenitor cells. PMID:25257881

[Ventilatory dysfunction in motor neuron disease: when and how to act?].

PubMed

Rocha, J Afonso; Miranda, M J

2007-01-01

Amyotrophic lateral sclerosis is a devastating progressive neurodegenerative disorder, involving motor neurons in the cerebral cortex, brainstem and spinal cord. Mean duration of survival from the time of diagnosis is around 15 months, being pulmonary complications and respiratory failure responsible for more than 85% of deaths. Albeit the inevitability of respiratory failure and short-term death, standardized intervention protocols have been shown to significantly delay the need for invasive ventilatory support, thus prolonging survival and enhancing quality of life. The authors present an intervention protocol based on clinical progression and respiratory parameters. Decisions regarding initiation of non-invasive positive pressure ventilation (NIPPV) and mechanically assisted coughing, depend on development of symptoms of hypoventilation and on objective deterioration of respiratory parameters especially in what concerns bulbar muscle function. These include maximum inspiratory capacity (MIC), difference between MIC and vital capacity (MIC-VC), and assisted peak cough flow (PCF). These standardized protocols along with patient and caregivers education, allow for improved quality of life, prolonged survival and delay or eventually prevent the need for tracheotomy and invasive ventilatory support. Supplemental oxygen should be avoided in these patients, since it precludes use of oxymetry as feedback for titrating NIPPV and MAC, and is associated with decreased ventilatory drive and aggravated hypercapnia.

Preparation of myeloid derived suppressor cells (MDSC) from naive and pancreatic tumor-bearing mice using flow cytometry and automated magnetic activated cell sorting (AutoMACS).

PubMed

Nelson, Nadine; Szekeres, Karoly; Cooper, Denise; Ghansah, Tomar

2012-06-18

MDSC are a heterogeneous population of immature macrophages, dendritic cells and granulocytes that accumulate in lymphoid organs in pathological conditions including parasitic infection, inflammation, traumatic stress, graft-versus-host disease, diabetes and cancer. In mice, MDSC express Mac-1 (CD11b) and Gr-1 (Ly6G and Ly6C) surface antigens. It is important to note that MDSC are well studied in various tumor-bearing hosts where they are significantly expanded and suppress anti-tumor immune responses compared to naïve counterparts. However, depending on the pathological condition, there are different subpopulations of MDSC with distinct mechanisms and targets of suppression. Therefore, effective methods to isolate viable MDSC populations are important in elucidating their different molecular mechanisms of suppression in vitro and in vivo. Recently, the Ghansah group has reported the expansion of MDSC in a murine pancreatic cancer model. Our tumor-bearing MDSC display a loss of homeostasis and increased suppressive function compared to naïve MDSC. MDSC percentages are significantly less in lymphoid compartments of naïve vs. tumor-bearing mice. This is a major caveat, which often hinders accurate comparative analyses of these MDSC. Therefore, enriching Gr-1(+) leukocytes from naïve mice prior to Fluorescence Activated Cell Sorting (FACS) enhances purity, viability and significantly reduces sort time. However, enrichment of Gr-1(+) leukocytes from tumor-bearing mice is optional as these are in abundance for quick FACS sorting. Therefore, in this protocol, we describe a highly efficient method of immunophenotyping MDSC and enriching Gr-1(+) leukocytes from spleens of naïve mice for sorting MDSC in a timely manner. Immunocompetent C57BL/6 mice are inoculated with murine Panc02 cells subcutaneously whereas naïve mice receive 1XPBS. Approximately 30 days post inoculation; spleens are harvested and processed into single-cell suspensions using a cell dissociation sieve. Splenocytes are then Red Blood Cell (RBC) lysed and an aliquot of these leukocytes are stained using fluorochrome-conjugated antibodies against Mac-1 and Gr-1 to immunophenotype MDSC percentages using Flow Cytometry. In a parallel experiment, whole leukocytes from naïve mice are stained with fluorescent-conjugated Gr-1 antibodies, incubated with PE-MicroBeads and positively selected using an automated Magnetic Activated Cell Sorting (autoMACS) Pro Separator. Next, an aliquot of Gr-1(+) leukocytes are stained with Mac-1 antibodies to identify the increase in MDSC percentages using Flow Cytometry. Now, these Gr1(+) enriched leukocytes are ready for FACS sorting of MDSC to be used in comparative analyses (naïve vs. tumor- bearing) in in vivo and in vitro assays.

42 CFR 423.2110 - MAC reviews on its own motion.

Code of Federal Regulations, 2011 CFR

2011-10-01

... its own motion, it will mail the results of its action to the enrollee and to CMS or the IRE, as... 42 Public Health 3 2011-10-01 2011-10-01 false MAC reviews on its own motion. 423.2110 Section 423..., and Judicial Review § 423.2110 MAC reviews on its own motion. (a) General rule. The MAC may decide on...

Troponin-only Manchester Acute Coronary Syndromes (T-MACS) decision aid: single biomarker re-derivation and external validation in three cohorts

PubMed Central

Body, Richard; Sperrin, Matthew; Lewis, Philip S; Burrows, Gillian; Carley, Simon; McDowell, Garry; Buchan, Iain; Greaves, Kim; Mackway-Jones, Kevin

2017-01-01

Background The original Manchester Acute Coronary Syndromes model (MACS) ‘rules in’ and ‘rules out’ acute coronary syndromes (ACS) using high sensitivity cardiac troponin T (hs-cTnT) and heart-type fatty acid binding protein (H-FABP) measured at admission. The latter is not always available. We aimed to refine and validate MACS as Troponin-only Manchester Acute Coronary Syndromes (T-MACS), cutting down the biomarkers to just hs-cTnT. Methods We present secondary analyses from four prospective diagnostic cohort studies including patients presenting to the ED with suspected ACS. Data were collected and hs-cTnT measured on arrival. The primary outcome was ACS, defined as prevalent acute myocardial infarction (AMI) or incident death, AMI or coronary revascularisation within 30 days. T-MACS was built in one cohort (derivation set) and validated in three external cohorts (validation set). Results At the ‘rule out’ threshold, in the derivation set (n=703), T-MACS had 99.3% (95% CI 97.3% to 99.9%) negative predictive value (NPV) and 98.7% (95.3%–99.8%) sensitivity for ACS, ‘ruling out’ 37.7% patients (specificity 47.6%, positive predictive value (PPV) 34.0%). In the validation set (n=1459), T-MACS had 99.3% (98.3%–99.8%) NPV and 98.1% (95.2%–99.5%) sensitivity, ‘ruling out’ 40.4% (n=590) patients (specificity 47.0%, PPV 23.9%). T-MACS would ‘rule in’ 10.1% and 4.7% patients in the respective sets, of which 100.0% and 91.3% had ACS. C-statistics for the original and refined rules were similar (T-MACS 0.91 vs MACS 0.90 on validation). Conclusions T-MACS could ‘rule out’ ACS in 40% of patients, while ‘ruling in’ 5% at highest risk using a single hs-cTnT measurement on arrival. As a clinical decision aid, T-MACS could therefore help to conserve healthcare resources. PMID:27565197

High molecular weight kininogen regulates platelet-leukocyte interactions by bridging Mac-1 and glycoprotein Ib.

PubMed

Chavakis, Triantafyllos; Santoso, Sentot; Clemetson, Kenneth J; Sachs, Ulrich J H; Isordia-Salas, Irma; Pixley, Robin A; Nawroth, Peter P; Colman, Robert W; Preissner, Klaus T

2003-11-14

Leukocyte-platelet interaction is important in mediating leukocyte adhesion to a thrombus and leukocyte recruitment to a site of vascular injury. This interaction is mediated at least in part by the beta2-integrin Mac-1 (CD11b/CD18) and its counter-receptor on platelets, glycoprotein Ibalpha (GPIbalpha). High molecular weight kininogen (HK) was previously shown to interact with both GPIbalpha and Mac-1 through its domains 3 and 5, respectively. In this study we investigated the ability of HK to interfere with the leukocyte-platelet interaction. In a purified system, HK binding to GPIbalpha was inhibited by HK domain 3 and the monoclonal antibody (mAb) SZ2, directed against the epitope 269-282 of GPIbalpha, whereas mAb AP1, directed to the region 201-268 of GPIbalpha had no effect. In contrast, mAb AP1 inhibited the Mac-1-GPIbalpha interaction. Binding of GPIbalpha to Mac-1 was enhanced 2-fold by HK. This effect of HK was abrogated in the presence of HK domains 3 or 5 or peptides from the 475-497 region of the carboxyl terminus of domain 5 as well as in the presence of mAb SZ2 but not mAb AP1. Whereas no difference in the affinity of the Mac-1-GPIbalpha interaction was observed in the absence or presence of HK, maximal binding of GPIbalpha to Mac-1 doubled in the presence of HK. Moreover, HK/HKa increased the Mac-1-dependent adhesion of myelomonocytic U937 cells and K562 cells transfected with Mac-1 to immobilized GPIbalpha or to GPIbalpha-transfected Chinese hamster ovary cells. Finally, Mac-1-dependent adhesion of neutrophils to surface-adherent platelets was enhanced by HK. Thus, HK can bridge leukocytes with platelets by interacting via its domain 3 with GPIbalpha and via its domain 5 with Mac-1 thereby augmenting the Mac-1-GPIbalpha interaction. These distinct molecular interactions of HK with leukocytes and platelets contribute to the regulation of the adhesive behavior of vascular cells and provide novel molecular targets for reducing atherothrombotic pathologies.

Age correction in cognitive, linguistic, and motor domains for infants born preterm: an analysis of the Bayley Scales of Infant and Toddler Development, Third Edition developmental patterns.

PubMed

Morsan, Valentina; Fantoni, Carlo; Tallandini, Maria Anna

2018-03-15

To verify whether it is appropriate to use age correction for infants born preterm in all the developmental domains (cognitive, linguistic, and motor) considered by the Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-III). Seventy-three infants born preterm (26-35wks) without major neurological sequelae and 67 infants born at term were assessed at 12 months (corrected age for infants born preterm). The performance of the infants born preterm was assessed with two different evaluations: scores based on uncorrected age and scores based on corrected age. The developmental trends of infants born at term and infants born preterm differ across domains. Statistical analysis shows that age correction produces an overrated estimate of motor performance (12.5 points [95% confidence interval 9.05-16.01]) but not of cognitive performance. Given the broad use of the Bayley-III by psychologists and paediatricians, these results are important in the early diagnosis of developmental difficulties for children born preterm. Correction for gestational age should be applied for the cognitive domain only; whereas for the motor domain, chronological age should be used. No clear data emerged for language. Age correction with Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-III) for infants born preterm should be applied differently in cognitive, language, and motor domains. Using corrected age with Bayley-III, the motor skills are overrated. Correction for preterm births adequately measures cognitive skills. No clear indication emerged about language skills. © 2018 Mac Keith Press.

Predictors of Use of Monitored Anesthesia Care for Outpatient Gastrointestinal Endoscopy in a Capitated Payment System.

PubMed

Adams, Megan A; Prenovost, Katherine M; Dominitz, Jason A; Holleman, Robert G; Kerr, Eve A; Krein, Sarah L; Saini, Sameer D; Rubenstein, Joel H

2017-12-01

Use of monitored anesthesia care (MAC) for gastrointestinal endoscopy has increased in the Veterans Health Administration (VHA) as in fee-for-service environments, despite the absence of financial incentives. We investigated factors associated with use of MAC in an integrated health care delivery system with a capitated payment model. We performed a retrospective cohort study using multilevel logistic regression, with MAC use modeled as a function of procedure year, patient- and provider-level factors, and facility effects. We collected data from 2,091,590 veterans who underwent outpatient esophagogastroduodenoscopy and/or colonoscopy during fiscal years 2000-2013 at 133 facilities. The adjusted rate of MAC use in the VHA increased 17% per year (odds ratio for increase, 1.17; 95% confidence interval, 1.09-1.27) from fiscal year 2000 through 2013. The most rapid increase occurred starting in 2011. VHA use of MAC was associated with patient-level factors that included obesity, obstructive sleep apnea, higher comorbidity, and use of prescription opioids and/or benzodiazepines, although the magnitude of these effects was small. Provider-level and facility factors were also associated with use of MAC, although again the magnitude of these associations was small. Unmeasured facility-level effects had the greatest effect on the trend of MAC use. In a retrospective study of veterans who underwent outpatient esophagogastroduodenoscopy and/or colonoscopy from fiscal year 2000 through 2013, we found that even in a capitated system, patient factors are only weakly associated with use of MAC. Facility-level effects are the most prominent factor influencing increasing use of MAC. Future studies should focus on better defining the role of MAC and facility and organizational factors that affect choice of endoscopic sedation. It will also be important to align resources and incentives to promote appropriate allocation of MAC based on clinically meaningful patient factors. Copyright © 2017 AGA Institute. Published by Elsevier Inc. All rights reserved.

Annexin V-MACS in infertile couples as method for separation of sperm without DNA fragmentation.

PubMed

Troya, Jhon; Zorrilla, Ingrid

2015-05-01

To determine the effect of using MACS technology on clinical pregnancy, as a method for separation of damaged sperm in infertile patients. 136 infertile men having normal semen parameters in accordance with WHO 2010 criterion, undergoing ICSI cycle were enrolled during the course of the study. The patients were prospectively randomized and enrolled after oocyte retrieval and were assigned to the ICSI group, PICSI group or MACS group. Embryo development and clinical pregnancy were assessed. In 17 randomized MACS patients, sperm DNA fragmentation was tested in the presumptive apoptotic and no apoptotic spermatozoa fractions. Similar results were obtained between groups for the following parameters: fertilization rates of 78.97% (95% confidence interval [CI]:74.37-83.57), 70.15 %(95% CI:63.98-76.33) and 80.28%(95% CI:73.74-86.81) for ICSI, PICSI and MACS group, respectively; Number of Day-3 embryos was 5.04 (95% CI:4.09-5.98), 5.17(95% CI:4.24-6.10) and 5.59(95% CI:4.31-6.87) for ICSI, PICSI and MACS group, respectively; number of freezing embryos in blastocyst stage was 0.78 (95% CI:0.25- 1.31), 0.70(95% CI:0.27-1.14) and 1 (95% CI:0.37-1.6) for ICSI, PICSI and MACS group, respectively. However, clinical pregnancy rates of 58.1% for MACS group versus 40.4% and 27.3% for PICSI and ICSI group, respectively, were showed statistical difference (P=0.019). DNA fragmentation index for the two sperm MACS fraction showed statistical differences (P=0.000), MACS reduced the D.F.I of the sperm sample. The use of MACS technology improves the clinical pregnancy on infertile couples and can be applied as a method for sperm separation, discriminating sperm with high DNA fragmentation.

Cluster based architecture and network maintenance protocol for medical priority aware cognitive radio based hospital.

PubMed

Al Mamoon, Ishtiak; Muzahidul Islam, A K M; Baharun, Sabariah; Ahmed, Ashir; Komaki, Shozo

2016-08-01

Due to the rapid growth of wireless medical devices in near future, wireless healthcare services may face some inescapable issue such as medical spectrum scarcity, electromagnetic interference (EMI), bandwidth constraint, security and finally medical data communication model. To mitigate these issues, cognitive radio (CR) or opportunistic radio network enabled wireless technology is suitable for the upcoming wireless healthcare system. The up-to-date research on CR based healthcare has exposed some developments on EMI and spectrum problems. However, the investigation recommendation on system design and network model for CR enabled hospital is rare. Thus, this research designs a hierarchy based hybrid network architecture and network maintenance protocols for previously proposed CR hospital system, known as CogMed. In the previous study, the detail architecture of CogMed and its maintenance protocols were not present. The proposed architecture includes clustering concepts for cognitive base stations and non-medical devices. Two cluster head (CH selector equations are formulated based on priority of location, device, mobility rate of devices and number of accessible channels. In order to maintain the integrity of the proposed network model, node joining and node leaving protocols are also proposed. Finally, the simulation results show that the proposed network maintenance time is very low for emergency medical devices (average maintenance period 9.5 ms) and the re-clustering effects for different mobility enabled non-medical devices are also balanced.

Assessing children’s competence to consent in research by a standardized tool: a validity study

PubMed Central

2012-01-01

Background Currently over 50% of drugs prescribed to children have not been evaluated properly for use in their age group. One key reason why children have been excluded from clinical trials is that they are not considered able to exercise meaningful autonomy over the decision to participate. Dutch law states that competence to consent can be presumed present at the age of 12 and above; however, in pediatric practice children’s competence is not that clearly presented and the transition from assent to active consent is gradual. A gold standard for competence assessment in children does not exist. In this article we describe a study protocol on the development of a standardized tool for assessing competence to consent in research in children and adolescents. Methods/design In this study we modified the MacCAT-CR, the best evaluated competence assessment tool for adults, for use in children and adolescents. We will administer the tool prospectively to a cohort of pediatric patients from 6 to18 years during the selection stages of ongoing clinical trials. The outcomes of the MacCAT-CR interviews will be compared to a reference standard, established by the judgments of clinical investigators, and an expert panel consisting of child psychiatrists, child psychologists and medical ethicists. The reliability, criterion-related validity and reproducibility of the tool will be determined. As MacCAT-CR is a multi-item scale consisting of 13 items, power was justified at 130–190 subjects, providing a minimum of 10–15 observations per item. MacCAT-CR outcomes will be correlated with age, life experience, IQ, ethnicity, socio-economic status and competence judgment of the parent(s). It is anticipated that 160 participants will be recruited over 2 years to complete enrollment. Discussion A validity study on an assessment tool of competence to consent is strongly needed in research practice, particularly in the child and adolescent population. In this study we will establish a reference standard of children’s competence to consent, combined with validation of an assessment instrument. Results can facilitate responsible involvement of children in clinical trials by further development of guidelines, health-care policies and legal policies. PMID:23009102

Improvement of Eustachian Tube Function by Tissue-Engineered Regeneration of Mastoid Air Cells

PubMed Central

Kanemaru, Shin-ichi; Umeda, Hiroo; Yamashita, Masaru; Hiraumi, Harukazu; Hirano, Shigeru; Nakamura, Tatsuo; Ito, Juichi

2013-01-01

Objectives/Hypothesis Most cases of chronic otitis media (OMC) are associated with poor development of the mastoid air cells (MACs) and poor Eustachian tube (ET) function. We have previously reported that MAC regeneration can effectively eliminate intractable OMC. In this study, we assessed the ability of regenerated MACs to restore normal gas exchange function and contribute to improved ET function. Study Design Clinical trial with control. Setting General hospitals. Materials and Methods Seventy-six patients with OMC, including cholesteatoma and adhesive otitis media, received tympanoplasty and MAC regeneration therapy. At the first-stage of tympanoplasty, artificial pneumatic bones and/or autologous bone fragments were implanted into the opened mastoid cavity. At the 2nd-stage operation, a nitrous oxide (N2O) gas study was performed in 10 patients to measure middle ear pressure (MEP). For the control group, MEP was measured in five patients with good MAC development during cochlear implantation or facial nerve decompression. ET function was measured twice in each patient, once before the 1st operation and 6 months after the second operation. Results At the 2nd-stage operation, in all cases with regenerated MACs and in the normal control group, MEP changed after administration of N2O. In contrast, no change in MEP was observed in cases with unregenerated MACs. In 70% (n = 37/53) of the regenerated MAC group, ET function was improved, whereas improvement of ET function was observed in only 13% (n = 3/23) of the unregenerated MAC group. Conclusions Tissue-engineered regeneration of MACs improves ET function and gas exchange in the middle ear. Laryngoscope, 2012 Level of Evidence 3b PMID:23086494

Coronary artery calcification correlates with the presence and severity of valve calcification.

PubMed

Koulaouzidis, G; Nicoll, R; MacArthur, T; Jenkins, P J; Henein, M Y

2013-10-15

To investigate the prevalence of coronary artery calcification (CAC) in symptomatic individuals with CT evidence for left heart valve calcification, aortic valve (AVC), mitral valve (MAC) or both. This is a retrospective study of 282 consecutive patients with calcification in either the aortic valve or mitral annulus. Calcium scoring of the coronary artery, aortic and mitral valve was measured using the Agatston score. AVC was more prevalent than MAC (64% vs. 2.5%, p < 0.001), with 34% having both. Absence of CAC was noted in 12.7% of the study population. AVC + CAC were observed in 53.5%, MAC and CAC in 2.1%, and combined AVC, MAC and CAC in 31.6%. The median CAC score was higher in individuals with combined AVC+MAC, followed by those with AVC and lowest was in the MAC group. The majority (40%) of individuals with AVC had CAC score >400, and only in 16% had CAC = 0. The same pattern was more evident in individuals with AVC + MAC, where 70% had CAC score >400 and only 6% had CAC score of 0. These results were irrespective of gender. There was no correlation between AVC and MAC but there was modest correlation between CAC score and AVC score (r = 0.28, p = 0.0001), MAC (r = 0.36, p = 0.0001) and with combined AVC + MAC (r = 0.5, p = 0.0001). AVC score of 262 had a sensitivity of 78% and specificity of 92% for the prediction of presence of CAC. The presence and extent of calcification in the aortic valve or/and mitral valves are associated with severe coronary artery calcification. © 2013.

Pleiotrophin, a multifunctional cytokine and growth factor, induces leukocyte responses through the integrin Mac-1.

PubMed

Shen, Di; Podolnikova, Nataly P; Yakubenko, Valentin P; Ardell, Christopher L; Balabiyev, Arnat; Ugarova, Tatiana P; Wang, Xu

2017-11-17

Pleiotrophin (PTN) is a multifunctional, cationic, glycosaminoglycan-binding cytokine and growth factor involved in numerous physiological and pathological processes, including tissue repair and inflammation-related diseases. PTN has been shown to promote leukocyte responses by inducing their migration and expression of inflammatory cytokines. However, the mechanisms through which PTN mediates these responses remain unclear. Here, we identified the integrin Mac-1 (αMβ2, CD11b/CD18) as the receptor mediating macrophage adhesion and migration to PTN. We also found that expression of Mac-1 on the surface of human embryonic kidney (HEK) 293 cells induced their adhesion and migration to PTN. Accordingly, PTN promoted Mac-1-dependent cell spreading and initiated intracellular signaling manifested in phosphorylation of Erk1/2. While binding to PTN, Mac-1 on Mac-1-expressing HEK293 cells appears to cooperate with cell-surface proteoglycans because both anti-Mac-1 function-blocking mAb and heparin were required to block adhesion. Moreover, biolayer interferometry and NMR indicated a direct interaction between the α M I domain, the major ligand-binding region of Mac-1, and PTN. Using peptide libraries, we found that in PTN the α M I domain bound sequences enriched in basic and hydrophobic residues, indicating that PTN conforms to the general principle of ligand-recognition specificity of the α M I domain toward cationic proteins/peptides. Finally, using recombinant PTN-derived fragments, we show that PTN contains two distinct Mac-1-binding sites in each of its constitutive domains. Collectively, these results identify PTN as a ligand for the integrin Mac-1 on the surface of leukocytes and suggest that this interaction may play a role in inflammatory responses. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

EFFECTS OF TRAMADOL ON THE MINIMUM ANESTHETIC CONCENTRATION OF ISOFLURANE IN WHITE-EYED PARAKEETS (PSITTACARA LEUCOPHTHALMUS).

PubMed

Escobar, André; da Rocha, Rozana Wendler; Midon, Monica; de Almeida, Ricardo Miyasaka; Filho, Darcio Zangirolami; Werther, Karin

2017-06-01

The aim of this study was to determine the minimum anesthetic concentration (MAC) of isoflurane, and to investigate if tramadol changes the isoflurane MAC in white-eyed parakeets (Psittacara leucophthalmus). Ten adult birds weighing 157 ± 9 g were anesthetized with isoflurane in oxygen under mechanical ventilation. Isoflurane concentration for the first bird was adjusted to 2.2%, and after 15 min an electrical stimulus was applied in the thigh area to observe the response (movement or nonmovement). Isoflurane concentration for the subsequent bird was increased by 10% if the previous bird moved, or decreased by 10% if the previous bird did not move. This procedure was performed serially until at least four sequential crossover events were detected. A crossover event was defined as a sequence of two birds with different responses (positive or negative) to the electrical stimulus. Isoflurane MAC was calculated as the mean isoflurane concentration value at the crossover events. After 1 wk, the same birds were reanesthetized with isoflurane and MAC was determined at 15 and 30 min after intramuscular administration of 10 mg/kg of tramadol using the same method. A paired t-test (P < 0.05%) was used to detect significant differences for MAC between treatments. Isoflurane MAC in this population of white-eyed parakeets was 2.47 ± 0.09%. Isoflurane MAC values 15 and 30 min after tramadol administration were indistinguishable from each other (pooled value was 2.50 ± 0.18%); they were also indistinguishable from isoflurane MAC without tramadol. The isoflurane MAC value in white-eyed parakeets is higher than reported for other bird species. Tramadol (10 mg/kg, i.m.) does not change isoflurane MAC in these birds.

Randomized controlled trial of a home-visiting intervention on infant cognitive development in peri-urban South Africa.

PubMed

Murray, Lynne; Cooper, Peter; Arteche, Adriane; Stein, Alan; Tomlinson, Mark

2016-03-01

To determine whether, in an impoverished South African community, an intervention that benefitted infant attachment also benefitted cognitive development. Pregnant females were randomized to intervention (n=220) and no-treatment control groups (n=229). The intervention was home-based parenting support for attachment, delivered until 6 months postpartum. At 18 months, infants were assessed on attachment and cognitive development (Bayley Scales Mental Development Index [MDI]) (n=127 intervention, n=136 control participants). Infant MDI was examined in relation to intervention, socio-economic risk, antenatal depression, and infant sex and attachment. Overall, there was little effect of the intervention on MDI (p=0.094, d=0.20), but there was an interaction between intervention and risk (p=0.03, ηp2=0.02). MDI scores of infants of lower risk intervention group mothers were, on average, 4.84 points higher than those of other infants (p=0.002, d=0.41). Antenatal depression was not significant once intervention and risk were controlled (p=0.08); there was no association between infant MDI and either sex (p=0.41) or attachment (p=0.56). Parenting interventions for infant cognitive development may benefit from inclusion of specific components to support infant cognition beyond those that support attachment, and may be most effective for infants over 6 months. They may need augmentation with other input where adversity is extreme. © 2015 Mac Keith Press.

Motor development in 3-month-old healthy term-born infants is associated with cognitive and behavioural outcomes at early school age.

PubMed

Hitzert, Marrit M; Roze, Elise; Van Braeckel, Koenraad N J A; Bos, Arend F

2014-09-01

To determine whether motor development at 3 months of age is associated with cognitive, motor, and behavioural outcomes in healthy children at early school age. In this cohort study, we included 74 term-born, healthy children (44 males, 30 females; median gestational age 40.1 wks, range 38.0-42.6 wks). From video recordings (median 12.9 wks, range 9.3-18.6 wks), we assessed the quality of fidgety movements, and calculated a motor optimality score. At school age (median 5 y 11 mo, range 5 y 8 mo-7 y 6 mo), we performed detailed cognitive, motor, and behavioural assessments. We examined whether aspects of motor development were associated with functional outcomes. An age-adequate motor repertoire, in particular the presence of antigravity, midline leg, and manipulation movements, was related to poorer cognition, whereas variable finger postures was related to better cognition. Children with a monotonous concurrent motor repertoire had better ball skills but experienced more behavioural problems. The presence of antigravity movements tended to be associated with abnormal recognition (odds ratio [OR] 4.4, 95% confidence interval [CI], 0.9-21; R(2) =0.17; p=0.070), where the absence of variable finger postures was associated with borderline and abnormal visual-spatial perception (OR 20, 95% CI, 1.7-238; R(2) =0.39; p=0.018). Detailed aspects of motor development at 3 months of age are associated with cognition and behaviour, but not with motor outcome, in healthy children at early school age. Our findings suggest that early motor development may be the basis for later cognitive and behavioural performance. Since the associations were only moderate, possible environmental influences should be acknowledged. © 2014 Mac Keith Press.

Evaluating a cognitive/ecological program for the prevention of aggression among urban children.

PubMed

Huesmann, L R; Maxwell, C D; Eron, L; Dahlberg, L L; Guerra, N G; Tolan, P H; VanAcker, R; Henry, D

1996-01-01

The Metropolitan Area Child Study (MACS) is a multifaceted school- and family-based intervention and evaluation study designed to prevent and understand the development of aggressive behavior. The multifaceted interventions are grounded in combined social-cognitive and ecologic theories. Social-cognitive theories contend that cognitive scripts, attributions, and beliefs acquired early in life mediate the effects of ecological factors that influence the development of antisocial behavior. Prevention programs aimed at these cognitions must address multiple dimensions of the child's environment including family, peer, school, and community. The program has three levels of intervention delivered in two-year segments: (1) Level 1: a general enhancement classroom intervention that stresses culturally sensitive student and teacher interaction involving instructional and classroom management strategies and a social-cognitive curriculum that mitigates aggressive development; (2) Level 2: intensive small-group sessions designed to change children's cognitions and enhance peer relationship skills for at-risk children added to the general classroom enhancement program; and (3) Level 3: a one-year family relationship intervention that stresses parenting skill building and emotional responsiveness in family interactions added to the general enhancement and small-group training conditions. Sixteen Chicago-area schools are randomly assigned (four each) to a control group or one of the three intervention levels. Individual child assessment, peer assessments, classroom behavioral observations, and archival data are collected before the interventions begin, during the interventions, at the end of each intervention, and at a follow-up point. The pretests indicate that the children on average have higher levels of aggression than found nationally and elevated clinical levels of other psychopathologies. Across the four intervention levels there are no significant differences in ethnic composition, socio-economic status (SES), aggressive behavior, and normative beliefs about aggression.

CCSDS Advanced Orbiting Systems Virtual Channel Access Service for QoS MACHETE Model

NASA Technical Reports Server (NTRS)

Jennings, Esther H.; Segui, John S.

2011-01-01

To support various communications requirements imposed by different missions, interplanetary communication protocols need to be designed, validated, and evaluated carefully. Multimission Advanced Communications Hybrid Environment for Test and Evaluation (MACHETE), described in "Simulator of Space Communication Networks" (NPO-41373), NASA Tech Briefs, Vol. 29, No. 8 (August 2005), p. 44, combines various tools for simulation and performance analysis of space networks. The MACHETE environment supports orbital analysis, link budget analysis, communications network simulations, and hardware-in-the-loop testing. By building abstract behavioral models of network protocols, one can validate performance after identifying the appropriate metrics of interest. The innovators have extended the MACHETE model library to include a generic link-layer Virtual Channel (VC) model supporting quality-of-service (QoS) controls based on IP streams. The main purpose of this generic Virtual Channel model addition was to interface fine-grain flow-based QoS (quality of service) between the network and MAC layers of the QualNet simulator, a commercial component of MACHETE. This software model adds the capability of mapping IP streams, based on header fields, to virtual channel numbers, allowing extended QoS handling at link layer. This feature further refines the QoS v existing at the network layer. QoS at the network layer (e.g. diffserv) supports few QoS classes, so data from one class will be aggregated together; differentiating between flows internal to a class/priority is not supported. By adding QoS classification capability between network and MAC layers through VC, one maps multiple VCs onto the same physical link. Users then specify different VC weights, and different queuing and scheduling policies at the link layer. This VC model supports system performance analysis of various virtual channel link-layer QoS queuing schemes independent of the network-layer QoS systems.

Re-engineering Nascom's network management architecture

NASA Technical Reports Server (NTRS)

Drake, Brian C.; Messent, David

1994-01-01

The development of Nascom systems for ground communications began in 1958 with Project Vanguard. The low-speed systems (rates less than 9.6 Kbs) were developed following existing standards; but, there were no comparable standards for high-speed systems. As a result, these systems were developed using custom protocols and custom hardware. Technology has made enormous strides since the ground support systems were implemented. Standards for computer equipment, software, and high-speed communications exist and the performance of current workstations exceeds that of the mainframes used in the development of the ground systems. Nascom is in the process of upgrading its ground support systems and providing additional services. The Message Switching System (MSS), Communications Address Processor (CAP), and Multiplexer/Demultiplexer (MDM) Automated Control System (MACS) are all examples of Nascom systems developed using standards such as, X-windows, Motif, and Simple Network Management Protocol (SNMP). Also, the Earth Observing System (EOS) Communications (Ecom) project is stressing standards as an integral part of its network. The move towards standards has produced a reduction in development, maintenance, and interoperability costs, while providing operational quality improvement. The Facility and Resource Manager (FARM) project has been established to integrate the Nascom networks and systems into a common network management architecture. The maximization of standards and implementation of computer automation in the architecture will lead to continued cost reductions and increased operational efficiency. The first step has been to derive overall Nascom requirements and identify the functionality common to all the current management systems. The identification of these common functions will enable the reuse of processes in the management architecture and promote increased use of automation throughout the Nascom network. The MSS, CAP, MACS, and Ecom projects have indicated the potential value of commercial-off-the-shelf (COTS) and standards through reduced cost and high quality. The FARM will allow the application of the lessons learned from these projects to all future Nascom systems.

EISCAT observations during MAC/SINE and MAC/Epsilon

NASA Technical Reports Server (NTRS)

Roettger, J.; Hoppe, U.-P.; Hall, C.

1989-01-01

The EISCAT incoherent scatter radar facility in Tromsoe, Norway was operated during the MAC/SINE campaign for 78 hours in the period 10 June to 17 July 1987, and during the MAC/Epsilon campaign for 90 hours in the period 15 October to 5 November 1987. The VHF (224 MHz) radar operations during MAC/SINE yielded most interesting observations of strong coherent echoes from the mesopause region. Characteristic data of these polar mesospheric summer echoes are presented. The UHF (933 MHz) radar operations during MAC/Epsilon were done with 18 deg off zenith beam and allows the deduction of meridonal and horizontal wind components as well as radial velocity spectra in addition to the usual electron density profiles in the D and lower E regions. Some results from the VHF and UHF radars indicating the presence of gravity waves are examined.

Mutational screening of CHX10, GDF6, OTX2, RAX and SOX2 genes in 50 unrelated microphthalmia-anophthalmia-coloboma (MAC) spectrum cases.

PubMed

Gonzalez-Rodriguez, J; Pelcastre, E L; Tovilla-Canales, J L; Garcia-Ortiz, J E; Amato-Almanza, M; Villanueva-Mendoza, C; Espinosa-Mattar, Z; Zenteno, J C

2010-08-01

Microphthalmia-anophthalmia-coloboma (MAC) are congenital eye malformations causing a significant percentage of visually impairments in children. Although these anomalies can arise from prenatal exposure to teratogens, mutations in well-defined genes originate potentially heritable forms of MAC. Mutations in genes such as CHX10, GDF6, RAX, SOX2 and OTX2, among others, have been recognised in dominant or recessive MAC. SOX2 and OTX2 are the two most commonly mutated genes in monogenic MAC. However, as more numerous samples of MAC subjects would be analysed, a better estimation of the actual involvement of specific MAC-genes could be made. Here, a comprehensive mutational analysis of the CHX10, GDF6, RAX, SOX2 and OTX2 genes was performed in 50 MAC subjects. PCR amplification and direct automated DNA sequencing of all five genes in 50 unrelated subjects. Eight mutations (16% prevalence) were recognised, including four GDF6 mutations (one novel), two novel RAX mutations, one novel OTX2 mutation and one SOX2 mutation. Anophthalmia and nanophthalmia, not previously associated with GDF6 mutations, were observed in two subjects carrying defects in this gene, expanding the spectrum of GDF6-linked ocular anomalies. Our study underscores the importance of genotyping large groups of patients from distinct ethnic origins for improving the estimation of the global involvement of particular MAC-causing genes.

Cognitive-behavioral group treatment for social phobia in adolescents. A preliminary study.

PubMed

Albano, A M; Marten, P A; Holt, C S; Heimberg, R G; Barlow, D H

1995-10-01

The present study is a preliminary evaluation of the effectiveness of a new cognitive-behavioral group treatment protocol for social phobia in adolescents. Five adolescents with social phobia were treated in a 16-session group treatment program, with parental involvement in selected sessions. Treatment involved skills training (social skills, problem solving, assertiveness), cognitive restructuring, behavioral exposure, and homework. Self-report measures of anxiety and depression, taken throughout treatment, indicated significant improvements over a 1-year follow-up period. Behavior test measures also indicated a decrease in subjective anxiety ratings after treatment which was maintained at follow-up. Structured diagnostic interviews 1 year after treatment confirmed full remission of social phobia for four subjects, with one subject's phobia in partial remission. Overall, the present findings support the continued evaluation of this protocol for social phobic adolescents.

Collision avoidance in TV white spaces: a cross-layer design approach for cognitive radio networks

NASA Astrophysics Data System (ADS)

Foukalas, Fotis; Karetsos, George T.

2015-07-01

One of the most promising applications of cognitive radio networks (CRNs) is the efficient exploitation of TV white spaces (TVWSs) for enhancing the performance of wireless networks. In this paper, we propose a cross-layer design (CLD) of carrier sense multiple access with collision avoidance (CSMA/CA) mechanism at the medium access control (MAC) layer with spectrum sensing (SpSe) at the physical layer, for identifying the occupancy status of TV bands. The proposed CLD relies on a Markov chain model with a state pair containing both the SpSe and the CSMA/CA from which we derive the collision probability and the achievable throughput. Analytical and simulation results are obtained for different collision avoidance and SpSe implementation scenarios by varying the contention window, back off stage and probability of detection. The obtained results depict the achievable throughput under different collision avoidance and SpSe implementation scenarios indicating thereby the performance of collision avoidance in TVWSs-based CRNs.

Examining Expertise Using Interviews and Verbal Protocols

ERIC Educational Resources Information Center

van de Wiel, Margje W. J.

2017-01-01

To understand expertise and expertise development, interactions between knowledge, cognitive processing and task characteristics must be examined in people at different levels of training, experience, and performance. Interviewing is widely used in the initial exploration of domain expertise. Work and cognitive task analysis chart the knowledge,…

Behavioral and Neural Correlates of Imagined Walking and Walking-While-Talking in the Elderly

PubMed Central

Blumen, Helena M.; Holtzer, Roee; Brown, Lucy L.; Gazes, Yunglin; Verghese, Joe

2014-01-01

Cognition is important for locomotion and gait decline increases the risk for morbidity, mortality, cognitive decline, and dementia. Yet, the neural correlates of gait are not well established, because most neuroimaging methods cannot image the brain during locomotion. Imagined gait protocols overcome this limitation. This study examined the behavioral and neural correlates of a new imagined gait protocol that involved imagined walking (iW), imagined talking (iT), and imagined walking-while-talking (iWWT). In Experiment 1, 82 cognitively-healthy older adults (M = 80.45) walked (W), iW, walked while talking (WWT) and iWWT. Real and imagined walking task times were strongly correlated, particularly real and imagined dual-task times (WWT and iWWT). In Experiment 2, 33 cognitively-healthy older adults (M = 73.03) iW, iT, and iWWT during functional Magnetic Resonance Imaging. A multivariate Ordinal Trend (OrT) Covariance analysis identified a pattern of brain regions that: 1) varied as a function of imagery task difficulty (iW, iT and iWWT), 2) involved cerebellar, precuneus, supplementary motor and other prefrontal regions, and 3) were associated with kinesthetic imagery ratings and behavioral performance during actual WWT. This is the first study to compare the behavioral and neural correlates of imagined gait in single and dual-task situations, an issue that is particularly relevant to elderly populations. These initial findings encourage further research and development of this imagined gait protocol as a tool for improving gait and cognition among the elderly. PMID:24522972

A critical evaluation of magnetic activated carbon's potential for the remediation of sediment impacted by polycyclic aromatic hydrocarbons.

PubMed

Han, Zhantao; Sani, Badruddeen; Akkanen, Jarkko; Abel, Sebastian; Nybom, Inna; Karapanagioti, Hrissi K; Werner, David

2015-04-09

Addition of activated carbon (AC) or biochar (BC) to sediment to reduce the chemical and biological availability of organic contaminants is a promising in-situ remediation technology. But concerns about leaving the adsorbed pollutants in place motivate research into sorbent recovery methods. This study explores the use of magnetic sorbents. A coal-based magnetic activated carbon (MAC) was identified as the strongest of four AC and BC derived magnetic sorbents for polycyclic aromatic hydrocarbons (PAHs) remediation. An 8.1% MAC amendment (w/w, equal to 5% AC content) was found to be as effective as 5% (w/w) pristine AC in reducing aqueous PAHs within three months by 98%. MAC recovery from sediment after three months was 77%, and incomplete MAC recovery had both, positive and negative effects. A slight rebound of aqueous PAH concentrations was observed following the MAC recovery, but aqueous PAH concentrations then dropped again after six months, likely due to the presence of the 23% unrecovered MAC. On the other hand, the 77% recovery of the 8.1% MAC dose was insufficient to reduce ecotoxic effects of fine grained AC or MAC amendment on the egestion rate, growth and reproduction of the AC sensitive species Lumbriculus variegatus. Copyright © 2014 Elsevier B.V. All rights reserved.

The microassay on a card: A rugged, portable immunoassay

NASA Technical Reports Server (NTRS)

Kidwell, David

1991-01-01

The Microassay on a Card (MAC) is a portable, hand-held, non-instrumental immunoassay that can test for the presence of a wide variety of substances in the environment. The MAC is a simple device to use. A drop of test solution is placed on one side of the card and within five minutes a color is developed on the other side in proportion to the amount of substance in the test solution, with sensitivity approaching 10 ng/ml. The MAC is self-contained and self-timed; no reagents or timing is necessary. The MAC may be configured with multiple wells to provide simultaneous testing for multiple species. As envisioned, the MAC will be employed first as an on-site screen for drugs of abuse in urine or saliva. If the MAC can be used as a screen of saliva for drugs of abuse, it could be applied to driving while intoxicated, use of drugs on the job, or testing of the identity of seized materials. With appropriate modifications, the MAC also could be used to test for environmental toxins or pollutants.

AeroMACS system characterization and demonstrations

NASA Astrophysics Data System (ADS)

Kerczewski, R. J.; Apaza, R. D.; Dimond, R. P.

This The Aeronautical Mobile Airport Communications System (AeroMACS) is being developed to provide a new broadband wireless communications capability for safety critical communications in the airport surface domain, providing connectivity to aircraft and other ground vehicles as well as connections between other critical airport fixed assets. AeroMACS development has progressed from requirements definition through technology definition, prototype deployment and testing, and now into national and international standards development. The first prototype AeroMACS system has been deployed at the Cleveland Hopkins International Airport (CLE) and the adjacent NASA Glenn Research Center (GRC). During the past three years, extensive technical testing has taken place to characterize the performance of the AeroMACS prototype and provide technical support for the standards development process. The testing has characterized AeroMACS link and network performance over a variety of conditions for both fixed and mobile data transmission and has included basic system performance testing and fixed and mobile applications testing. This paper provides a summary of the AeroMACS performance testing and the status of standardization activities that the testing supports.

AeroMACS System Characterization and Demonstrations

NASA Technical Reports Server (NTRS)

Kerczewski, Robert J.; Apaza, Rafael D.; Dimond, Robert P.

2013-01-01

This The Aeronautical Mobile Airport Communications System (AeroMACS) is being developed to provide a new broadband wireless communications capability for safety critical communications in the airport surface domain, providing connectivity to aircraft and other ground vehicles as well as connections between other critical airport fixed assets. AeroMACS development has progressed from requirements definition through technology definition, prototype deployment and testing, and now into national and international standards development. The first prototype AeroMACS system has been deployed at the Cleveland Hopkins International Airport (CLE) and the adjacent NASA Glenn Research Center (GRC). During the past 3 years, extensive technical testing has taken place to characterize the performance of the AeroMACS prototype and provide technical support for the standards development process. The testing has characterized AeroMACS link and network performance over a variety of conditions for both fixed and mobile data transmission and has included basic system performance testing and fixed and mobile applications testing. This paper provides a summary of the AeroMACS performance testing and the status of standardization activities that the testing supports.

AeroMACS System Characterization and Demonstrations

NASA Technical Reports Server (NTRS)

Kerczewski, Robert J.; Apaza, Rafael D.; Dimond, Robert P.

2013-01-01

The Aeronautical Mobile Airport Communications System (AeroMACS) is being developed to provide a new broadband wireless communications capability for safety critical communications in the airport surface domain, providing connectivity to aircraft and other ground vehicles as well as connections between other critical airport fixed assets. AeroMACS development has progressed from requirements definition through technology definition, prototype deployment and testing, and now into national and international standards development. The first prototype AeroMACS system has been deployed at the Cleveland Hopkins International Airport (CLE) and the adjacent NASA Glenn Research Center (GRC). During the past three years, extensive technical testing has taken place to characterize the performance of the AeroMACS prototype and provide technical support for the standards development process. The testing has characterized AeroMACS link and network performance over a variety of conditions for both fixed and mobile data transmission and has included basic system performance testing and fixed and mobile applications testing. This paper provides a summary of the AeroMACS performance testing and the status of standardization activities that the testing supports.

Cross-layer protocol design for QoS optimization in real-time wireless sensor networks

NASA Astrophysics Data System (ADS)

Hortos, William S.

2010-04-01

The metrics of quality of service (QoS) for each sensor type in a wireless sensor network can be associated with metrics for multimedia that describe the quality of fused information, e.g., throughput, delay, jitter, packet error rate, information correlation, etc. These QoS metrics are typically set at the highest, or application, layer of the protocol stack to ensure that performance requirements for each type of sensor data are satisfied. Application-layer metrics, in turn, depend on the support of the lower protocol layers: session, transport, network, data link (MAC), and physical. The dependencies of the QoS metrics on the performance of the higher layers of the Open System Interconnection (OSI) reference model of the WSN protocol, together with that of the lower three layers, are the basis for a comprehensive approach to QoS optimization for multiple sensor types in a general WSN model. The cross-layer design accounts for the distributed power consumption along energy-constrained routes and their constituent nodes. Following the author's previous work, the cross-layer interactions in the WSN protocol are represented by a set of concatenated protocol parameters and enabling resource levels. The "best" cross-layer designs to achieve optimal QoS are established by applying the general theory of martingale representations to the parameterized multivariate point processes (MVPPs) for discrete random events occurring in the WSN. Adaptive control of network behavior through the cross-layer design is realized through the parametric factorization of the stochastic conditional rates of the MVPPs. The cross-layer protocol parameters for optimal QoS are determined in terms of solutions to stochastic dynamic programming conditions derived from models of transient flows for heterogeneous sensor data and aggregate information over a finite time horizon. Markov state processes, embedded within the complex combinatorial history of WSN events, are more computationally tractable and lead to simplifications for any simulated or analytical performance evaluations of the cross-layer designs.

Evaluating the Effects of Interface Disruption Using fNIR Spectroscopy

DTIC Science & Technology

2011-02-28

Error Potentials in Brain- Computer Interfaces. ADVANCES IN COGNITIVE NEURODYNAMICS , 2008: p. 777-782. 21. Nieuwenhuis S, et al., Psychophysiology...introduced until the 1990‟s and holds great potential for extremely non-invasive cognitive state measurement. It is significantly easier and faster to...As a reminder, the general protocol is as follows: 1) Researchers gather benchmark tasks from cognitive psychology that elicit high and low

33 CFR 334.630 - Tampa Bay south of MacDill Air Force Base, Fla.; small-arms firing range and aircraft jettison, U...

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Tampa Bay south of MacDill Air Force Base, Fla.; small-arms firing range and aircraft jettison, U.S. Air Force, MacDill Air Force Base... Force Base, Fla.; small-arms firing range and aircraft jettison, U.S. Air Force, MacDill Air Force Base...

33 CFR 334.630 - Tampa Bay south of MacDill Air Force Base, Fla.; small-arms firing range and aircraft jettison, U...

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 3 2014-07-01 2014-07-01 false Tampa Bay south of MacDill Air Force Base, Fla.; small-arms firing range and aircraft jettison, U.S. Air Force, MacDill Air Force Base... Force Base, Fla.; small-arms firing range and aircraft jettison, U.S. Air Force, MacDill Air Force Base...

33 CFR 334.630 - Tampa Bay south of MacDill Air Force Base, Fla.; small-arms firing range and aircraft jettison, U...

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 3 2012-07-01 2012-07-01 false Tampa Bay south of MacDill Air Force Base, Fla.; small-arms firing range and aircraft jettison, U.S. Air Force, MacDill Air Force Base... Force Base, Fla.; small-arms firing range and aircraft jettison, U.S. Air Force, MacDill Air Force Base...

33 CFR 334.630 - Tampa Bay south of MacDill Air Force Base, Fla.; small-arms firing range and aircraft jettison, U...

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 3 2013-07-01 2013-07-01 false Tampa Bay south of MacDill Air Force Base, Fla.; small-arms firing range and aircraft jettison, U.S. Air Force, MacDill Air Force Base... Force Base, Fla.; small-arms firing range and aircraft jettison, U.S. Air Force, MacDill Air Force Base...

Impact of MAC Delay on AUV Localization: Underwater Localization Based on Hyperbolic Frequency Modulation Signal

PubMed Central

2018-01-01

Medium Access Control (MAC) delay which occurs between the anchor node’s transmissions is one of the error sources in underwater localization. In particular, in AUV localization, the MAC delay significantly degrades the ranging accuracy. The Cramer-Rao Low Bound (CRLB) definition theoretically proves that the MAC delay significantly degrades the localization performance. This paper proposes underwater localization combined with multiple access technology to decouple the localization performance from the MAC delay. Towards this goal, we adopt hyperbolic frequency modulation (HFM) signal that provides multiplexing based on its good property, high-temporal correlation. Owing to the multiplexing ability of the HFM signal, the anchor nodes can transmit packets without MAC delay, i.e., simultaneous transmission is possible. In addition, the simulation results show that the simultaneous transmission is not an optional communication scheme, but essential for the localization of mobile object in underwater. PMID:29373518

Impact of MAC Delay on AUV Localization: Underwater Localization Based on Hyperbolic Frequency Modulation Signal.

PubMed

Kim, Sungryul; Yoo, Younghwan

2018-01-26

Medium Access Control (MAC) delay which occurs between the anchor node's transmissions is one of the error sources in underwater localization. In particular, in AUV localization, the MAC delay significantly degrades the ranging accuracy. The Cramer-Rao Low Bound (CRLB) definition theoretically proves that the MAC delay significantly degrades the localization performance. This paper proposes underwater localization combined with multiple access technology to decouple the localization performance from the MAC delay. Towards this goal, we adopt hyperbolic frequency modulation (HFM) signal that provides multiplexing based on its good property, high-temporal correlation. Owing to the multiplexing ability of the HFM signal, the anchor nodes can transmit packets without MAC delay, i.e., simultaneous transmission is possible. In addition, the simulation results show that the simultaneous transmission is not an optional communication scheme, but essential for the localization of mobile object in underwater.

Hypothalamic-Pituitary-Adrenal Axis Physiology and Cognitive Control of Behavior in Stress Inoculated Monkeys

ERIC Educational Resources Information Center

Parker, Karen J.; Buckmaster, Christine L.; Lindley, Steven E.; Schatzberg, Alan F.; Lyons, David M.

2012-01-01

Monkeys exposed to stress inoculation protocols early in life subsequently exhibit diminished neurobiological responses to moderate psychological stressors and enhanced cognitive control of behavior during juvenile development compared to non-inoculated monkeys. The present experiments extended these findings and revealed that stress inoculated…

Can Functional Brain Imaging Be Used to Explore Interactivity and Cognition in Multimedia Learning Environments?

ERIC Educational Resources Information Center

Dalgarno, Barney; Kennedy, Gregor; Bennett, Sue

2010-01-01

This paper reviews existing methods used to address questions about interactivity, cognition and learning in multimedia learning environments. Existing behavioural and self-report methods identified include observations, audit trails, questionnaires, interviews, video-stimulated recall, and think-aloud protocols. The limitations of these methods…

Cognitive Coaching: A Critical Phase in Professional Development to Implement Sheltered Instruction

ERIC Educational Resources Information Center

Batt, Ellen G.

2010-01-01

This documentary account describes professional development for teachers in the USA serving culturally and linguistically diverse students. The purpose of the project was to monitor effectiveness of training in Sheltered Instruction Observation Protocol (SIOP) and to assess the value of cognitive coaching. Quantitative and qualitative data sources…

Conceptual Transformation and Cognitive Processes in Origami Paper Folding

ERIC Educational Resources Information Center

Tenbrink, Thora; Taylor, Holly A.

2015-01-01

Research on problem solving typically does not address tasks that involve following detailed and/or illustrated step-by-step instructions. Such tasks are not seen as cognitively challenging problems to be solved. In this paper, we challenge this assumption by analyzing verbal protocols collected during an Origami folding task. Participants…

Stability of cognitive performance in children with mild intellectual disability.

PubMed

Jenni, Oskar G; Fintelmann, Sylvia; Caflisch, Jon; Latal, Beatrice; Rousson, Valentin; Chaouch, Aziz

2015-05-01

Longitudinal studies that have examined cognitive performance in children with intellectual disability more than twice over the course of their development are scarce. We assessed population and individual stability of cognitive performance in a clinical sample of children with borderline to mild non-syndromic intellectual disability. Thirty-six children (28 males, eight females; age range 3-19y) with borderline to mild intellectual disability (Full-scale IQ [FSIQ] 50-85) of unknown origin were examined in a retrospective clinical case series using linear mixed models including at least three assessments with standardized intelligence tests. Average cognitive performance remained remarkably stable over time (high population stability, drop of only 0.38 IQ points per year, standard error=0.39, p=0.325) whereas individual stability was at best moderate (intraclass correlation of 0.58), indicating that about 60% of the residual variation in FSIQ scores can be attributed to between-child variability. Neither sex nor socio-economic status had a statistically significant impact on FSIQ. Although intellectual disability during childhood is a relatively stable phenomenon, individual stability of IQ is only moderate, likely to be caused by test-to-test reliability (e.g. level of child's cooperation, motivation, and attention). Therefore, clinical decisions and predictions should not rely on single IQ assessments, but should also consider adaptive functioning and previous developmental history. © 2014 Mac Keith Press.

Atypical multifocal Dravet syndrome lacks generalized seizures and may show later cognitive decline.

PubMed

Kim, Young Ok; Bellows, Susannah; McMahon, Jacinta M; Iona, Xenia; Damiano, John; Dibbens, Leanne; Kelley, Kent; Gill, Deepak; Cross, J Helen; Berkovic, Samuel F; Scheffer, Ingrid E

2014-01-01

To show that atypical multifocal Dravet syndrome is a recognizable, electroclinical syndrome associated with sodium channel gene (SCN1A) mutations that readily escapes diagnosis owing to later cognitive decline and tonic seizures. Eight patients underwent electroclinical characterization. SCN1A was sequenced and copy number variations sought by multiplex ligation-dependent probe amplification. All patients were female (age range at assessment 5-26y) with median seizure onset at 6.5 months (range 4-19mo). The initial seizure was brief in seven and status epilepticus only occurred in one; three were febrile. Focal seizures occurred in four patients and bilateral convulsion in the other four. All patients developed multiple focal seizure types and bilateral convulsions, with seizure clusters in six. The most common focal seizure semiology (six out of eight) comprised unilateral clonic activity. Five also had focal or asymmetric tonic seizures. Rare or transient myoclonic seizures occurred in six individuals, often triggered by specific antiepileptic drugs. Developmental slowing occurred in all: six between 3 years and 8 years, and two around 1 year 6 months. Cognitive outcome varied from severe to mild intellectual disability. Multifocal epileptiform discharges were seen on electroencephalography. Seven out of eight patients had SCN1A mutations. Atypical, multifocal Dravet syndrome with SCN1A mutations may not be recognized because of later cognitive decline and frequent tonic seizures. © 2013 Mac Keith Press.

What the drivers do and do not tell you: using verbal protocol analysis to investigate driver behaviour in emergency situations.

PubMed

Banks, Victoria A; Stanton, Neville A; Harvey, Catherine

2014-01-01

Although task analysis of pedestrian detection can provide us with useful insights into how a driver may behave in emergency situations, the cognitive elements of driver decision-making are less well understood. To assist in the design of future Advanced Driver Assistance Systems, such as Autonomous Emergency Brake systems, it is essential that the cognitive elements of the driving task are better understood. This paper uses verbal protocol analysis in an exploratory fashion to uncover the thought processes underlying behavioural outcomes represented by hard data collected using the Southampton University Driving Simulator.

Accuracy of the MacArthur competence assessment tool for clinical research (MacCAT-CR) for measuring children's competence to consent to clinical research.

PubMed

Hein, Irma M; Troost, Pieter W; Lindeboom, Robert; Benninga, Marc A; Zwaan, C Michel; van Goudoever, Johannes B; Lindauer, Ramón J L

2014-12-01

An objective assessment of children's competence to consent to research participation is currently not possible. Age limits for asking children's consent vary considerably between countries, and, to our knowledge, the correlation between competence and children's age has never been systematically investigated. To test a standardized competence assessment instrument for children by modifying the MacArthur Competence Assessment Tool for Clinical Research (MacCAT-CR), to investigate its reliability and validity, and to examine the correlation of its assessment with age and estimate cutoff ages. This prospective study included children and adolescents aged 6 to 18 years in the inpatient and outpatient departments of allergology, gastroenterology, oncology, ophthalmology, and pulmonology from January 1, 2012, through January 1, 2014. Participants were eligible for clinical research studies, including observational studies and randomized clinical trials. Competence judgments by experts aware of the 4 relevant criteria-understanding, appreciation, reasoning, and choice-were used to establish the reference standard. The index test was the MacCAT-CR, which used a semistructured interview format. Interrater reliability, validity, and dimensionality of the MacCAT-CR and estimated cutoff ages for competence. Of 209 eligible patients, we included 161 (mean age, 10.6 years; 47.2% male). Good reproducibility of MacCAT-CR total and subscale scores was observed (intraclass correlation coefficient range, 0.68-0.92). We confirmed unidimensionality of the MacCAT-CR. By the reference standard, we judged 54 children (33.5%) to be incompetent; by the MacCAT-CR, 61 children (37.9%). Criterion-related validity of MacCAT-CR scores was supported by high overall accuracy in correctly classifying children as competent against the reference standard (area under the receiver operating characteristics curve, 0.78). Age was a good predictor of competence on the MacCAT-CR (area under the receiver operating characteristics curve, 0.90). In children younger than 9.6 years, competence was unlikely (sensitivity, 90%); in those older than 11.2 years, competence was probable (specificity, 90%). The optimal cutoff age was 10.4 years (sensitivity, 81%; specificity, 84%). The MacCAT-CR demonstrated strong psychometric properties. In children aged 9.6 to 11.2 years, consent may be justified when competence can be demonstrated in individual cases by the MacCAT-CR. The results contribute to a scientific underpinning of regulations for clinical research directed toward children.

Effect of Mitral Annular Calcium on Left Ventricular Diastolic Parameters.

PubMed

Codolosa, Jose N; Koshkelashvili, Nikoloz; Alnabelsi, Talal; Goykhman, Igor; Romero-Corral, Abel; Pressman, Gregg S

2016-03-01

Assessment of left ventricular (LV) diastolic function by Doppler flow imaging and tissue Doppler is an integral part of the echocardiographic examination. Mitral annular calcium (MAC) is frequently encountered on echocardiography. The aim of this study was to assess the impact of MAC, quantitatively measured by computed tomography scan, on echocardiographic LV diastolic parameters. We included 155 patients aged ≥65 years. Computed tomography reconstructions of the mitral annulus were created, and calcium identified and quantified by Agatston technique. Calcium locations were assigned using an overlaid template depicting the annular segments in relation to surrounding anatomic structures. Echocardiographic assessment of diastolic function was performed in standard fashion. Mean age was 77 years; 49% were men; and 43% were black. Patients with MAC had lower septal e' (p = 0.003), lateral e' (p = 0.04), and average e' (p = 0.01) compared with those without MAC. They also had a higher E-wave velocity (p = 0.01) and E/e' ratio (p <0.001). When evaluated by severity of MAC, and after adjustment for multiple clinical factors, there was a graded (inverse) relation between MAC severity and septal e' (p = 0.01), lateral e' (p = 0.01), and average e' (p = 0.01). In conclusion, LV diastolic parameters, as measured by Doppler echocardiography, are altered in the presence of MAC. This could be due to direct effects of MAC on annular function or might reflect truly reduced diastolic function. Interpretation of diastolic parameters in patients with MAC should be performed with caution. Copyright © 2016 Elsevier Inc. All rights reserved.

M. leprae components induce nerve damage by complement activation: identification of lipoarabinomannan as the dominant complement activator.

PubMed

Bahia El Idrissi, Nawal; Das, Pranab K; Fluiter, Kees; Rosa, Patricia S; Vreijling, Jeroen; Troost, Dirk; Morgan, B Paul; Baas, Frank; Ramaglia, Valeria

2015-05-01

Peripheral nerve damage is the hallmark of leprosy pathology but its etiology is unclear. We previously identified the membrane attack complex (MAC) of the complement system as a key determinant of post-traumatic nerve damage and demonstrated that its inhibition is neuroprotective. Here, we determined the contribution of the MAC to nerve damage caused by Mycobacterium leprae and its components in mouse. Furthermore, we studied the association between MAC and the key M. leprae component lipoarabinomannan (LAM) in nerve biopsies of leprosy patients. Intraneural injections of M. leprae sonicate induced MAC deposition and pathological changes in the mouse nerve, whereas MAC inhibition preserved myelin and axons. Complement activation occurred mainly via the lectin pathway and the principal activator was LAM. In leprosy nerves, the extent of LAM and MAC immunoreactivity was robust and significantly higher in multibacillary compared to paucibacillary donors (p = 0.01 and p = 0.001, respectively), with a highly significant association between LAM and MAC in the diseased samples (r = 0.9601, p = 0.0001). Further, MAC co-localized with LAM on axons, pointing to a role for this M. leprae antigen in complement activation and nerve damage in leprosy. Our findings demonstrate that MAC contributes to nerve damage in a model of M. leprae-induced nerve injury and its inhibition is neuroprotective. In addition, our data identified LAM as the key pathogen associated molecule that activates complement and causes nerve damage. Taken together our data imply an important role of complement in nerve damage in leprosy and may inform the development of novel therapeutics for patients.

Clinical Application of Standardized Cognitive Assessment Using fMRI. I. Matrix Reasoning

PubMed Central

Allen, Mark D.; Fong, Alina K.

2008-01-01

Functional MRI is increasingly recognized for its potential as a powerful new tool in clinical neuropsychology. This is likely due to the fact that, with some degree of innovation, it is possible to convert practically any familiar cognitive test into one that can be performed in the MRI scanning environment. However, like any assessment approach, meaningful interpretation of fMRI data for the purpose of patient evaluation crucially requires normative data derived from a sample of unimpaired persons, against which individual patients may be compared. Currently, no such normative data are available for any fMRI-based cognitive testing protocol. In this paper, we report the first of a series of fMRI-compatible cognitive assessment protocols, a matrix reasoning test (f-MRT), for which normative samples of functional activation have been collected from unimpaired control subjects and structured in a manner that makes individual patient evaluation possible in terms of familiar z-score distributions. Practical application of the f-MRT is demonstrated via a contrastive case-study of two individuals with cognitive impairment in which fMRI data identifies subtleties in patient deficits otherwise missed by conventional measures of performance. PMID:19641250

An augmented cognitive behavioural therapy for treating post-stroke depression: description of a treatment protocol.

PubMed

Kootker, Joyce A; Rasquin, Sascha M C; Smits, Peter; Geurts, Alexander C; van Heugten, Caroline M; Fasotti, Luciano

2015-09-01

Currently, no evidence-based treatment is available for mood problems after stroke. We present a new psychological intervention designed to reduce depressive complaints after stroke. This intervention was based on cognitive behavioural therapy principles and was shown feasible in a pilot study. In order to meet the specific needs of stroke patients (concerning both sensori-motor, cognitive, and behavioural problems), we incorporated motivational interviewing, grief resolution, and psycho-education. We emphasised for each session to take into account the cognitive deficits of the patients (i.e. be concrete, accessible, structured, specific, and repeat information). Moreover, we augmented the psychologist-administered therapy with the contribution of an occupational or movement therapist aimed at facilitating patients' goal-setting and attainment. The intervention consisted of 12 one-hour sessions with a psychologist and three or four one-hour sessions with an occupational or movement therapist. Currently, the effectiveness of the intervention is evaluated in a randomised controlled trial. The proposed psychological treatment protocol is innovative, as it applies cognitive behavioural therapy in a stroke-specific manner; moreover, it supports goal attainment by incorporating occupational or movement therapy sessions. © The Author(s) 2014.

Lunar Relay Satellite Network for Space Exploration: Architecture, Technologies and Challenges

NASA Technical Reports Server (NTRS)

Bhasin, Kul B.; Hackenberg, Anthony W.; Slywczak, Richard A.; Bose, Prasanta; Bergamo, Marcos; Hayden, Jeffrey L.

2006-01-01

NASA is planning a series of short and long duration human and robotic missions to explore the Moon and then Mars. A key objective of these missions is to grow, through a series of launches, a system of systems infrastructure with the capability for safe and sustainable autonomous operations at minimum cost while maximizing the exploration capabilities and science return. An incremental implementation process will enable a buildup of the communication, navigation, networking, computing, and informatics architectures to support human exploration missions in the vicinities and on the surfaces of the Moon and Mars. These architectures will support all space and surface nodes, including other orbiters, lander vehicles, humans in spacesuits, robots, rovers, human habitats, and pressurized vehicles. This paper describes the integration of an innovative MAC and networking technology with an equally innovative position-dependent, data routing, network technology. The MAC technology provides the relay spacecraft with the capability to autonomously discover neighbor spacecraft and surface nodes, establish variable-rate links and communicate simultaneously with multiple in-space and surface clients at varying and rapidly changing distances while making optimum use of the available power. The networking technology uses attitude sensors, a time synchronization protocol and occasional orbit-corrections to maintain awareness of its instantaneous position and attitude in space as well as the orbital or surface location of its communication clients. A position-dependent data routing capability is used in the communication relay satellites to handle the movement of data among any of multiple clients (including Earth) that may be simultaneously in view; and if not in view, the relay will temporarily store the data from a client source and download it when the destination client comes into view. The integration of the MAC and data routing networking technologies would enable a relay satellite system to provide end-to-end communication services for robotic and human missions in the vicinity, or on the surface of the Moon with a minimum of Earth-based operational support.

Spermatozoa with numerical chromosomal abnormalities are more prone to be retained by Annexin V-MACS columns.

PubMed

Esbert, M; Godo, A; Soares, S R; Florensa, M; Amorós, D; Ballesteros, A; Vidal, F

2017-07-01

Colloidal super-paramagnetic microbeads conjugated with annexin V are effective for separating apoptotic spermatozoa by MACS as a result of the high affinity of annexin V for externalized PS molecules. The effectiveness of the procedure in reducing the percentage of sperm with fragmented DNA and abnormal morphology has also been reported. However, it is still unknown if it could decrease the percentage of aneuploid spermatozoa. The objective of our prospective study, performed on 16 males with abnormal FISH on spermatozoa, was to assess if MACS columns were useful tools to retain spermatozoa carrying chromosomal abnormalities in semen samples processed after density gradient centrifugation (DGC). The pellet obtained after DGC was subjected to MACS, and sperm FISH analyses were performed both in the eluded fraction and in the fraction retained in the column. The observed frequencies of disomy and nullisomy 13, 18, and 21, X and Y, as well as the diploidy rates in the MACS eluded fraction and the fraction retained in the MACS column were recorded. We observed that the frequencies of aneuploidies in the eluded fraction were lower than in the fraction retained in the MACS column (0.59% vs. 0.75%; p = 0.010). DGC determined a significant reduction in sperm concentration (z-ratio = 2.83; p = 0.005) and a significant increase in sperm progressive motility (z-ratio = -3.5; p < 0.001). MACS also led to a significant reduction in sperm concentration (z-ratio = 3.14; p = 0.002) and a significant increase in progressive motility (z-ratio = -2.59; p = 0.01) when compared with the post-DGC sample. Sperm concentration was similar in the two fractions generated by MACS (z-ratio = 0.63; p = 0.52), while progressive motility was significantly higher in the MACS eluded fraction (z-ratio = 2.42; p = 0.02). According to our results, MACS columns are able to selectively retain spermatozoa carrying chromosomal abnormalities. Furthermore, the performance of DGC and MACS on semen samples leads to an enrichment of progressive motility. © 2017 American Society of Andrology and European Academy of Andrology.

Mycobacterium avium complex--the role of potable water in disease transmission.

PubMed

Whiley, H; Keegan, A; Giglio, S; Bentham, R

2012-08-01

Mycobacterium avium complex (MAC) is a group of opportunistic pathogens of major public health concern. It is responsible for a wide spectrum of disease dependent on subspecies, route of infection and patients pre-existing conditions. Presently, there is limited research on the incidence of MAC infection that considers both pulmonary and other clinical manifestations. MAC has been isolated from various terrestrial and aquatic environments including natural waters, engineered water systems and soils. Identifying the specific environmental sources responsible for human infection is essential in minimizing disease prevalence. This paper reviews current literature and case studies regarding the wide spectrum of disease caused by MAC and the role of potable water in disease transmission. Potable water was recognized as a putative pathway for MAC infection. Contaminated potable water sources associated with human infection included warm water distribution systems, showers, faucets, household drinking water, swimming pools and hot tub spas. MAC can maintain long-term contamination of potable water sources through its high resistance to disinfectants, association with biofilms and intracellular parasitism of free-living protozoa. Further research is required to investigate the efficiency of water treatment processes against MAC and into construction and maintenance of warm water distribution systems and the role they play in MAC proliferation. No claim to Australian Government works Journal of Applied Microbiology © 2012 The Society for Applied Microbiology.

NF-κB is involved in the LPS-mediated proliferation and apoptosis of MAC-T epithelial cells as part of the subacute ruminal acidosis response in cows.

PubMed

Fan, Wen-Jie; Li, He-Ping; Zhu, He-Shui; Sui, Shi-Ping; Chen, Pei-Ge; Deng, Yue; Sui, Tong-Ming; Wang, Yue-Ying

2016-11-01

To determine the effect of NF-κB on cell proliferation and apoptosis, we investigate the expression of inflammation and apoptosis-related factors in the bovine mammary epithelial cell line, MAC-T. MAC-T cells were cultured in vitro and MTT and LDH assays used to determine the effects of lipopolysaccharide (LPS) on proliferation and cytotoxicity respectively. RT-PCR and western blotting were used to evaluate the effect of LPS and NF-κB inhibition [pyrrolidine dithiocarbamate (PDTC) treatment] on the expression of inflammation and apoptosis-related factors. LPS significantly inhibited MAC-T cell proliferation in a dose- and time-dependent manner. Furthermore, LPS promoted apoptosis while the NF-кB inhibitor PDTC attenuated this effect. After LPS treatment, the NF-кB signaling pathway was activated, and the expression of inflammation and apoptosis-related factors increased. When PDTC blocked NF-кB signaling, the expression of inflammation and apoptosis-related factors were decreased in MAC-T cells. LPS activates the TLR4/NF-κB signaling pathway, inhibits proliferation and promotes apoptosis in MAC-T cells. NF-кB inhibition attenuates MAC-T cell apoptosis and TLR4/NF-κB signaling pathway. NF-кB inhibitor alleviating MAC-T cell apoptosis is presumably modulated by NF-кB.

Purification of human induced pluripotent stem cell-derived neural precursors using magnetic activated cell sorting.

PubMed

Rodrigues, Gonçalo M C; Fernandes, Tiago G; Rodrigues, Carlos A V; Cabral, Joaquim M S; Diogo, Maria Margarida

2015-01-01

Neural precursor (NP) cells derived from human induced pluripotent stem cells (hiPSCs), and their neuronal progeny, will play an important role in disease modeling, drug screening tests, central nervous system development studies, and may even become valuable for regenerative medicine treatments. Nonetheless, it is challenging to obtain homogeneous and synchronously differentiated NP populations from hiPSCs, and after neural commitment many pluripotent stem cells remain in the differentiated cultures. Here, we describe an efficient and simple protocol to differentiate hiPSC-derived NPs in 12 days, and we include a final purification stage where Tra-1-60+ pluripotent stem cells (PSCs) are removed using magnetic activated cell sorting (MACS), leaving the NP population nearly free of PSCs.

An Ultra-Low Power and Flexible Acoustic Modem Design to Develop Energy-Efficient Underwater Sensor Networks

PubMed Central

Sánchez, Antonio; Blanc, Sara; Yuste, Pedro; Perles, Angel; Serrano, Juan José

2012-01-01

This paper is focused on the description of the physical layer of a new acoustic modem called ITACA. The modem architecture includes as a major novelty an ultra-low power asynchronous wake-up system implementation for underwater acoustic transmission that is based on a low-cost off-the-shelf RFID peripheral integrated circuit. This feature enables a reduced power dissipation of 10 μW in stand-by mode and registers very low power values during reception and transmission. The modem also incorporates clear channel assessment (CCA) to support CSMA-based medium access control (MAC) layer protocols. The design is part of a compact platform for a long-life short/medium range underwater wireless sensor network. PMID:22969324

An ultra-low power and flexible acoustic modem design to develop energy-efficient underwater sensor networks.

PubMed

Sánchez, Antonio; Blanc, Sara; Yuste, Pedro; Perles, Angel; Serrano, Juan José

2012-01-01

This paper is focused on the description of the physical layer of a new acoustic modem called ITACA. The modem architecture includes as a major novelty an ultra-low power asynchronous wake-up system implementation for underwater acoustic transmission that is based on a low-cost off-the-shelf RFID peripheral integrated circuit. This feature enables a reduced power dissipation of 10 μW in stand-by mode and registers very low power values during reception and transmission. The modem also incorporates clear channel assessment (CCA) to support CSMA-based medium access control (MAC) layer protocols. The design is part of a compact platform for a long-life short/medium range underwater wireless sensor network.

The utilization of unified protocols in behavioral cognitive therapy in transdiagnostic group subjects: A clinical trial.

PubMed

de Ornelas Maia, Ana Claudia Corrêa; Nardi, Antonio Egidio; Cardoso, Adriana

2015-02-01

The practicing of protocols based on behavioral cognitive therapy (CBT) have been frequently used in the last decades and adapted to better manage the necessities of patients and providers. The goal is to build a treatment that is evidence-based - for that reason the unified protocol for multiple emotional disorders (transdiagnostics) have been utilized to simplify treatment - without losing scientific traits. The main goal of this study is to evaluate the unified protocol in groups of patients with depression and anxiety disorders. In a pool of 48 subjects, divided in two groups, one was submitted to 12 intervention sessions of the unified protocol while the other was solely given medication. MINI, BAI and BDI were the instruments used at the beginning and at the end of treatment. The results were highly significant (p<0.001) in as much as with the improvement of anxiety and depressive disorders as it was in the group which was treated with the unified protocol compared with the group which was only given medication Limitations of this study were the number of sample participants and the non-randomization of subjects in both groups. Group therapy has not been largely implemented though it is deemed very useful for treatments when the unified protocol is used in transdiagnostic patients. Not only does it allow for emotional stabilizing and socialization but it also enables subjects with an altruistic feeling amongst themselves. Copyright © 2014 Elsevier B.V. All rights reserved.

Myeloablative Versus Reduced-Intensity Hematopoietic Cell Transplantation for Acute Myeloid Leukemia and Myelodysplastic Syndromes

PubMed Central

Pasquini, Marcelo C.; Logan, Brent R.; Wu, Juan; Devine, Steven M.; Porter, David L.; Maziarz, Richard T.; Warlick, Erica D.; Fernandez, Hugo F.; Alyea, Edwin P.; Hamadani, Mehdi; Bashey, Asad; Giralt, Sergio; Geller, Nancy L.; Leifer, Eric; Le-Rademacher, Jennifer; Mendizabal, Adam M.; Horowitz, Mary M.; Deeg, H. Joachim; Horwitz, Mitchell E.

2017-01-01

Purpose The optimal regimen intensity before allogeneic hematopoietic cell transplantation (HCT) is unknown. We hypothesized that lower treatment-related mortality (TRM) with reduced-intensity conditioning (RIC) would result in improved overall survival (OS) compared with myeloablative conditioning (MAC). To test this hypothesis, we performed a phase III randomized trial comparing MAC with RIC in patients with acute myeloid leukemia or myelodysplastic syndromes. Patients and Methods Patients age 18 to 65 years with HCT comorbidity index ≤ 4 and < 5% marrow myeloblasts pre-HCT were randomly assigned to receive MAC (n = 135) or RIC (n = 137) followed by HCT from HLA-matched related or unrelated donors. The primary end point was OS 18 months post–random assignment based on an intent-to-treat analysis. Secondary end points included relapse-free survival (RFS) and TRM. Results Planned enrollment was 356 patients; accrual ceased at 272 because of high relapse incidence with RIC versus MAC (48.3%; 95% CI, 39.6% to 56.4% and 13.5%; 95% CI, 8.3% to 19.8%, respectively; P < .001). At 18 months, OS for patients in the RIC arm was 67.7% (95% CI, 59.1% to 74.9%) versus 77.5% (95% CI, 69.4% to 83.7%) for those in the MAC arm (difference, 9.8%; 95% CI, −0.8% to 20.3%; P = .07). TRM with RIC was 4.4% (95% CI, 1.8% to 8.9%) versus 15.8% (95% CI, 10.2% to 22.5%) with MAC (P = .002). RFS with RIC was 47.3% (95% CI, 38.7% to 55.4%) versus 67.8% (95% CI, 59.1% to 75%) with MAC (P < .01). Conclusion OS was higher with MAC, but this was not statistically significant. RIC resulted in lower TRM but higher relapse rates compared with MAC, with a statistically significant advantage in RFS with MAC. These data support the use of MAC as the standard of care for fit patients with acute myeloid leukemia or myelodysplastic syndromes. PMID:28380315

Mitral Annular Calcification as a Possible Nidus for Endocarditis: A Descriptive Series with Bacteriological Differences Noted.

PubMed

Pressman, Gregg S; Rodriguez-Ziccardi, Mary; Gartman, Charles H; Obasare, Edinrin; Melendres, Emmanuel; Arguello, Vivian; Bhalla, Vikas

2017-06-01

Mitral annular calcification (MAC) is a chronic inflammatory process with similarities to atherosclerosis. It is common in elderly patients and those with renal dysfunction. Although MAC is associated with cardiovascular morbidity, its relationship to infective endocarditis is unclear. The aim of this study was to test the hypothesis that MAC would be prevalent in patients with mitral valve vegetations and that vegetations would frequently occur on calcific nodules. A secondary aim was to look for possible bacteriological differences between vegetations attached to the calcified annulus versus leaflet vegetations. We retrospectively reviewed all echocardiographic studies of patients with native mitral valve vegetations from January 2007 to August 2015 (N = 56). We searched for (1) presence of MAC, (2) location of MAC, and (3) vegetation location (on calcium deposits or distant). MAC was defined as focal echo brightness in a nodular or band-like pattern. The modified Duke criteria were used to confirm the diagnosis of infective endocarditis. Transthoracic, transesophageal, and three-dimensional echocardiograms (when available) at the time of infection were evaluated by a single reader. Twenty-eight subjects were infected with Staphylococcus aureus, 17 with a streptococcal species, and five with other organisms; blood cultures were sterile in 6. Thirty-four (61%) subjects had some degree of MAC, while 22 (39%) had none. Among those with MAC, the vegetation was located on the calcium deposits in 22 (65%), versus in 12 (35%) where it was not. Among all 56 subjects, when S. aureus was the infecting organism it was present on MAC in 16/28 (57%) versus 6/28 (21%; P = .01) for other bacterial species. By contrast, streptococcal infections more frequently involved the leaflets (16/17 [94%]) versus nonstreptococcal infections (18/39 [46%]; P = .0008). MAC may act as a nidus for infection especially with S. aureus. Differences in mechanism of attachment between S. aureus and streptococci may account for the observed difference in frequency of attachment of vegetations to MAC. Copyright © 2017 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.

Protocol Analysis as a Method for Analyzing Conversational Data.

ERIC Educational Resources Information Center

Aleman, Carlos G.; Vangelisti, Anita L.

Protocol analysis, a technique that uses people's verbal reports about their cognitions as they engage in an assigned task, has been used in a number of applications to provide insight into how people mentally plan, assess, and carry out those assignments. Using a system of networked computers where actors communicate with each other over…

Study protocol of a randomized controlled trial comparing integrative body-mind-spirit intervention and cognitive behavioral therapy in fostering quality of life of patients with lung cancer and their family caregivers.

PubMed

Lau, Bobo Hi-Po; Chow, Amy Y M; Wong, Daniel F K; Chan, Jessie S M; Chan, Celia H Y; Ho, Rainbow T H; So, Tsz-Him; Lam, Tai-Chung; Lee, Victor Ho-Fun; Lee, Anne W M; Chow, Sau Fong; Chan, Cecilia L W

2018-01-01

Compared to cancers at other sites, lung cancer often results in greater psychosocial distress to both the patients and their caregivers, due to the poor prognosis and survival rate, as well as the heavy symptom burden. In recent years, making protocols of proposed or on-going studies publicly available via clinical trial registries and/or peer-reviewed journals has benefited health sciences with timely communication of the latest research trends and improved transparency in reporting. However, such practice is yet to be a common sight in evidence-informed social work. Hence, this paper discusses the value of publishing protocols in social work research and presents the protocol of a randomized controlled trial that compares the effectiveness of integrative body-mind-spirit intervention with cognitive behavioral therapy for enhancing quality of life of patients with lung cancer and their family caregivers. The data collection process was still on-going at the time of manuscript submission.

Alzheimer's Disease Assessment Scale - Cognitive Subscale (ADAS-Cog): Normative Data for the Portuguese Population.

PubMed

Nogueira, Joana; Freitas, Sandra; Duro, Diana; Tábuas-Pereira, Miguel; Guerreiro, Manuela; Almeida, Jorge; Santana, Isabel

2018-02-28

The Alzheimer's Disease Assessment Scale - Cognitive Subscale is a brief battery developed to assess cognitive functioning in Alzheimer's disease that encompasses the core characteristics of cognitive decline (e.g. memory, language, praxis, constructive ability and orientation). The early detection, as well as the monitoring of cognitive decline along disease progression, is extremely important in clinical care and interventional research. The main goals of the present study were to analyze the psychometric properties of the Portuguese version of the Alzheimer's Disease Assessment Scale - Cognitive Subscale, and to establish normative values for the Portuguese population. The Portuguese version of Alzheimer's Disease Assessment Scale - Cognitive Subscale was administered to 223 cognitively healthy participants according to a standard assessment protocol consisting of the Mini-Mental State Examination, the Montreal Cognitive Assessment and the Adults and Older Adults Functional Assessment Inventory. Normal performance on the assessment protocol was the inclusion criteria for the study. The Alzheimer's Disease Assessment Scale - Cognitive Subscale revealed good psychometric properties when used in the Portuguese population. Age was the main predictor of the Alzheimer's Disease Assessment Scale - Cognitive Subscale total score (R2 = 0.123), whereas the influence of education level was lower (R2 = 0.027). These two variables explained 14.4% of the variance on the Alzheimer's Disease Assessment Scale - Cognitive Subscale scores and were used to stratify the normative values for the Portuguese population presented here. On the total sample, the average total score in the Alzheimer's Disease Assessment Scale - Cognitive Subscale was 6 points. The normative data were determined according to age and educational level as these were the sociodemographic variables that significantly contributed to the prediction of the Alzheimer's Disease Assessment Scale - Cognitive Subscale total scores, explaining 14.4% of their variance. The normative data are of the utmost importance to ensure proper use of this battery in Portugal.

Interdisciplinary cognitive task analysis: a strategy to develop a comprehensive endoscopic retrograde cholangiopancreatography protocol for use in fellowship training.

PubMed

Canopy, Erin; Evans, Matt; Boehler, Margaret; Roberts, Nicole; Sanfey, Hilary; Mellinger, John

2015-10-01

Endoscopic retrograde cholangiopancreatography is a challenging procedure performed by surgeons and gastroenterologists. We employed cognitive task analysis to identify steps and decision points for this procedure. Standardized interviews were conducted with expert gastroenterologists (7) and surgeons (4) from 4 institutions. A procedural step and cognitive decision point protocol was created from audio-taped transcriptions and was refined by 5 additional surgeons. Conceptual elements, sequential actions, and decision points were iterated for 5 tasks: patient preparation, duodenal intubation, selective cannulation, imaging interpretation with related therapeutic intervention, and complication management. A total of 180 steps were identified. Gastroenterologists identified 34 steps not identified by surgeons, and surgeons identified 20 steps not identified by gastroenterologists. The findings suggest that for complex procedures performed by diverse practitioners, more experts may help delineate distinctive emphases differentiated by training background and type of practice. Copyright © 2015 Elsevier Inc. All rights reserved.

Randomized controlled trial of false safety behavior elimination therapy: a unified cognitive behavioral treatment for anxiety psychopathology.

PubMed

Schmidt, Norman B; Buckner, Julia D; Pusser, Andrea; Woolaway-Bickel, Kelly; Preston, Jennifer L; Norr, Aaron

2012-09-01

We tested the efficacy of a unified cognitive-behavioral therapy protocol for anxiety disorders. This group treatment protocol, termed false safety behavior elimination therapy (F-SET), is a cognitive-behavioral approach designed for use across various anxiety disorders such as panic disorder (PD), social anxiety disorder (SAD), and generalized anxiety disorder (GAD). F-SET simplifies, as well as broadens, key therapeutic elements of empirically validated treatments for anxiety disorders to allow for easier delivery to heterogeneous groups of patients with anxiety psychopathology. Patients with a primary anxiety disorder diagnosis (N=96) were randomly assigned to F-SET or a wait-list control. Data indicate that F-SET shows good efficacy and durability when delivered to mixed groups of patients with anxieties (i.e., PD, SAD, GAD) by relatively inexperienced clinicians. Findings are discussed in the context of balancing treatment efficacy and clinical utility. Copyright © 2012. Published by Elsevier Ltd.

The touchscreen operant platform for testing learning and memory in rats and mice

PubMed Central

Horner, Alexa E.; Heath, Christopher J.; Hvoslef-Eide, Martha; Kent, Brianne A.; Kim, Chi Hun; Nilsson, Simon R. O.; Alsiö, Johan; Oomen, Charlotte A.; Holmes, Andrew; Saksida, Lisa M.; Bussey, Timothy J.

2014-01-01

Summary An increasingly popular method of assessing cognitive functions in rodents is the automated touchscreen platform, on which a number of different cognitive tests can be run in a manner very similar to touchscreen methods currently used to test human subjects. This methodology is low stress (using appetitive, rather than aversive reinforcement), has high translational potential, and lends itself to a high degree of standardisation and throughput. Applications include the study of cognition in rodent models of psychiatric and neurodegenerative diseases (e.g., Alzheimer’s disease, schizophrenia, Huntington’s disease, frontotemporal dementia), and characterisation of the role of select brain regions, neurotransmitter systems and genes in rodents. This protocol describes how to perform four touchscreen assays of learning and memory: Visual Discrimination, Object-Location Paired-Associates Learning, Visuomotor Conditional Learning and Autoshaping. It is accompanied by two further protocols using the touchscreen platform to assess executive function, working memory and pattern separation. PMID:24051959

C-MAC videolaryngoscope versus Macintosh laryngoscope for tracheal intubation: A systematic review and meta-analysis with trial sequential analysis.

PubMed

Hoshijima, Hiroshi; Mihara, Takahiro; Maruyama, Koichi; Denawa, Yohei; Mizuta, Kentaro; Shiga, Toshiya; Nagasaka, Hiroshi

2018-06-09

The C-MAC laryngoscope (C-MAC) is a videolaryngoscope that uses a modified Macintosh blade. Although several anecdotal reports exist, it remains unclear whether the C-MAC is superior to the Macintosh laryngoscope for tracheal intubation in the adult population. Systematic review, meta-analysis. Operating room, intensive care unit. For inclusion in our analysis, studies had to be prospective randomised trials which compared the C-MAC with the Macintosh laryngoscope for tracheal intubation in the adult population. Data on success rates, intubation time, glottic visualisation and incidence of external laryngeal manipulations (ELM) during tracheal intubation were extracted from the identified studies. In subgroup analysis, we separated those parameters to assess the influence of the airway condition (normal or difficult) and laryngoscopists (novice or experienced). We conducted a trial sequential analysis (TSA). Sixteen articles with 18 trials met the inclusion criteria. The C-MAC provided better glottic visualisation compared to the Macintosh (RR, 1.08; 95% CI, 1.03-1.14). TSA corrected the CI to 1.01-1.19; thus, total sample size reached the required information size (RIS). Success rates and intubation time did not differ significantly between the laryngoscopes. TSA showed that total sample size reached the RIS for success rates. The TSA Z curve surpassed the futility boundary. The C-MAC required less ELM compared to the Macintosh (RR, 0.83; 95% CI, 0.72-0.96). TSA corrected the CI to 0.67-1.03; 52.3% of the RIS was achieved. In difficult airways, the C-MAC showed superior success rates, glottic visualisation, and less ELM compared to the Macintosh. Among experienced laryngoscopists, the C-MAC offered better glottic visualisation with less ELM than the Macintosh. The C-MAC provided better glottic visualisation and less ELM (GRADE: Very Low or Moderate), with improved success rates, glottic visualisation, and less ELM in difficult airways. Copyright © 2018 Elsevier Inc. All rights reserved.

Enhancing creative cognition with a rapid right-parietal neurofeedback procedure.

PubMed

Agnoli, Sergio; Zanon, Marco; Mastria, Serena; Avenanti, Alessio; Corazza, Giovanni Emanuele

2018-02-14

The present article describes an innovative neurofeedback training (NFT) procedure aimed at increasing creative cognition through the enhancement of specific brain activities previously associated with divergent thinking. We designed and tested two NFT protocols based on training alpha and beta EEG oscillations selectively measured over the right parietal region. A total of 80 participants were involved, 40 in the alpha NFT protocol and 40 in the beta NFT protocol. The NFT loop was closed on a video stream that would advance only when oscillation power exceeded a normalized threshold. The total duration of the protocol was two hours in a single day, hence its classification as rapid. Changes in ideational fluency and originality, measured with a divergent thinking task, were compared between participants receiving real video feedback and participants receiving sham feedback. We controlled for individual differences in creative achievement level. Results showed that the protocols were effective at enhancing alpha and beta activities in the targeted area. Differences between the two protocols emerged in their effectiveness at promoting divergent thinking. While no significant changes in originality resulted from the rapid alpha NFT, increases in both originality and fluency emerged as a consequence of the rapid beta NFT. These results were particularly evident in participants starting with a low creative achievement level. Possible interpretations and future directions are proposed and discussed. Copyright © 2018 Elsevier Ltd. All rights reserved.

Human Subject Research Protocol: Computer-Aided Human Centric Cyber Situation Awareness: Understanding Cognitive Processes of Cyber Analysts

DTIC Science & Technology

2013-11-01

by existing cyber-attack detection tools far exceeds the analysts’ cognitive capabilities. Grounded in perceptual and cognitive theory , many visual...Processes Inspired by the sense-making theory discussed earlier, we model the analytical reasoning process of cyber analysts using three key...analyst are called “working hypotheses”); each hypothesis could trigger further actions to confirm or disconfirm it. New actions will lead to new

The NEIL Memory Research Unit: psychosocial, biological, physiological and lifestyle factors associated with healthy ageing: study protocol.

PubMed

Hannigan, Caoimhe; Coen, Robert F; Lawlor, Brian A; Robertson, Ian H; Brennan, Sabina

2015-01-01

Population ageing is a global phenomenon that has characterised demographic trends during the 20th and 21st century. The rapid growth in the proportion of older adults in the population, and resultant increase in the incidence of age-related cognitive decline, dementia and Alzheimer's disease, brings significant social, economic and healthcare challenges. Decline in cognitive abilities represents the most profound threat to active and healthy ageing. Current evidence suggests that a significant proportion of cases of age-related cognitive decline and dementia may be preventable through the modification of risk factors including education, depressive symptomology, physical activity, social engagement and participation in cognitively stimulating activities. The NEIL Memory Research Unit cohort study was established to investigate factors related to brain health and the maintenance of cognitive function. A cohort of 1000 normally ageing adults aged 50 years and over are being recruited to participate in comprehensive assessments at baseline, and at follow-up once every 2 years. The assessment protocol comprises a comprehensive neuropsychological battery, some basic physical measures, psychosocial scales, questionnaire measures related to a range of health, lifestyle and behavioural factors, and a measure of resting state activity using electroencephalography (EEG). The NEIL Memory Research Unit cohort study will address key questions about brain health and cognitive ageing in the population aged 50+, with a particular emphasis on the influence of potentially modifiable factors on cognitive outcomes. Analyses will be conducted with a focus on factors involved in the maintenance of cognitive function among older adults, and therefore will have the potential to contribute significant knowledge related to key questions within the field of cognitive ageing, and to inform the development of public health interventions aimed at preventing cognitive decline and promoting active and healthy ageing.

33 CFR 334.630 - Tampa Bay south of MacDill Air Force Base, Fla.; small-arms firing range and aircraft jettison, U...

Code of Federal Regulations, 2010 CFR

2010-07-01

... Force Base, Fla.; small-arms firing range and aircraft jettison, U.S. Air Force, MacDill Air Force Base... Force Base, Fla.; small-arms firing range and aircraft jettison, U.S. Air Force, MacDill Air Force Base...″, longitude 82°33′02.44″; and thence to a point on the shore line of MacDill Air Force Base at latitude 27°50...

Comparative study of MacCormack and TVD MacCormack schemes for three-dimensional separation at wing/body junctions in supersonic flows

NASA Technical Reports Server (NTRS)

Lakshmanan, Balakrishnan; Tiwari, Surendra N.

1992-01-01

A robust, discontinuity-resolving TVD MacCormack scheme containing no dependent parameters requiring adjustment is presently used to investigate the 3D separation of wing/body junction flows at supersonic speeds. Many production codes employing MacCormack schemes can be adapted to use this method. A numerical simulation of laminar supersonic junction flow is found to yield improved separation location predictions, as well as the axial velocity profiles in the separated flow region.

C-Band Airport Surface Communications System Standards Development. Phase II Final Report. Volume 2: Test Bed Performance Evaluation and Final AeroMACS Recommendations

NASA Technical Reports Server (NTRS)

Hall, Edward; Magner, James

2011-01-01

This report is provided as part of ITT s NASA Glenn Research Center Aerospace Communication Systems Technical Support (ACSTS) contract NNC05CA85C, Task 7: New ATM Requirements-Future Communications, C-Band and L-Band Communications Standard Development and was based on direction provided by FAA project-level agreements for New ATM Requirements-Future Communications. Task 7 included two subtasks. Subtask 7-1 addressed C-band (5091- to 5150-MHz) airport surface data communications standards development, systems engineering, test bed and prototype development, and tests and demonstrations to establish operational capability for the Aeronautical Mobile Airport Communications System (AeroMACS). Subtask 7-2 focused on systems engineering and development support of the L-band digital aeronautical communications system (L-DACS). Subtask 7-1 consisted of two phases. Phase I included development of AeroMACS concepts of use, requirements, architecture, and initial high-level safety risk assessment. Phase II builds on Phase I results and is presented in two volumes. Volume I is devoted to concepts of use, system requirements, and architecture, including AeroMACS design considerations. Volume II (this document) describes an AeroMACS prototype evaluation and presents final AeroMACS recommendations. This report also describes airport categorization and channelization methodologies. The purposes of the airport categorization task were (1) to facilitate initial AeroMACS architecture designs and enable budgetary projections by creating a set of airport categories based on common airport characteristics and design objectives, and (2) to offer high-level guidance to potential AeroMACS technology and policy development sponsors and service providers. A channelization plan methodology was developed because a common global methodology is needed to assure seamless interoperability among diverse AeroMACS services potentially supplied by multiple service providers.

Dendritic Cell-specific Intercellular Adhesion Molecule 3-grabbing Non-integrin (DC-SIGN) Recognizes a Novel Ligand, Mac-2-binding Protein, Characteristically Expressed on Human Colorectal Carcinomas*

PubMed Central

Nonaka, Motohiro; Ma, Bruce Yong; Imaeda, Hirotsugu; Kawabe, Keiko; Kawasaki, Nobuko; Hodohara, Keiko; Kawasaki, Nana; Andoh, Akira; Fujiyama, Yoshihide; Kawasaki, Toshisuke

2011-01-01

Dendritic cell (DC)-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN) is a type II transmembrane C-type lectin expressed on DCs such as myeloid DCs and monocyte-derived DCs (MoDCs). Recently, we have reported that DC-SIGN interacts with carcinoembryonic antigen (CEA) expressed on colorectal carcinoma cells. CEA is one of the most widely used tumor markers for gastrointestinal cancers such as colorectal cancer. On the other hand, other groups have reported that the level of Mac-2-binding protein (Mac-2BP) increases in patients with pancreatic, breast, and lung cancers, virus infections such as human immunodeficiency virus and hepatitis C virus, and autoimmune diseases. Here, we first identified Mac-2BP expressed on several colorectal carcinoma cell lines as a novel DC-SIGN ligand through affinity chromatography and mass spectrometry. Interestingly, we found that DC-SIGN selectively recognizes Mac-2BP derived from some colorectal carcinomas but not from the other ones. Furthermore, we found that the α1-3,4-fucose moieties of Le glycans expressed on DC-SIGN-binding Mac-2BP were important for recognition. DC-SIGN-dependent cellular interactions between immature MoDCs and colorectal carcinoma cells significantly inhibited MoDC functional maturation, suggesting that Mac-2BP may provide a tolerogenic microenvironment for colorectal carcinoma cells through DC-SIGN-dependent recognition. Importantly, Mac-2BP was detected as a predominant DC-SIGN ligand expressed on some primary colorectal cancer tissues from certain parts of patients in comparison with CEA from other parts, suggesting that DC-SIGN-binding Mac-2BP bearing tumor-associated Le glycans may become a novel potential colorectal cancer biomarker for some patients instead of CEA. PMID:21515679

Staging of Macular Telangiectasia: Power-Doppler Optical Coherence Tomography and Macular Pigment Optical Density

PubMed Central

Chin, Eric K.; Kim, Dae Yu; Hunter, Allan A.; Pilli, Suman; Wilson, Machelle; Zawadzki, Robert J.; Werner, John S.; Park, Susanna S.

2013-01-01

Purpose. Two methods were used to study the stages of macular telangiectasia (MacTel): Power-Doppler optical coherence tomography (PD-OCT), which allows imaging of the retinal circulation in three dimensions, and macular pigment optical density (MPOD), which quantifies the distribution of macular carotenoids. Methods. Among 49 patients with MacTel identified, 12 eyes (6 patients) with MacTel and 7 age-matched control eyes (7 patients) were imaged with a custom-built Fourier-domain OCT instrument to acquire PD-OCT images. MPOD was measured using heterochromatic flicker photometry in 10 eyes (5 patients) with MacTel and compared with 44 age-matched control eyes (44 patients). Clinical staging of MacTel was based on best-corrected visual acuity, fundus biomicroscopy, fluorescein angiography, and OCT. Results. Stage 1 eyes (n = 2) had subtle punctate vascular signal confined to the inner portion of the outer plexiform layer (OPL) on PD-OCT. Stage 2 (n = 2) showed larger oblique vascular signal extending into deeper OPL. Stage 3 (n = 5) had disruption of outer retinal layers with abnormal vasculature extending into the outer nuclear layer. Stage 4 (n = 3) showed diffuse blurring of the retinal layers with vascular channels extending the full thickness of the retina. MPOD values in four eyes with stage 1 or 2 MacTel correlated well with age-matched controls. Six eyes with stage 3 or 4 MacTel had loss of MPOD especially at the fovea. Conclusions. PD-OCT shows penetration of the retinal capillaries into the deeper retinal layers in early stages of MacTel, with full thickness vascular proliferation in advanced disease. MPOD is commonly depleted but may appear normal in early stage MacTel. PMID:23716628

C-Band Airport Surface Communications System Standards Development. Phase II Final Report. Volume 1: Concepts of Use, Initial System Requirements, Architecture, and AeroMACS Design Considerations

NASA Technical Reports Server (NTRS)

Hall, Edward; Isaacs, James; Henriksen, Steve; Zelkin, Natalie

2011-01-01

This report is provided as part of ITT s NASA Glenn Research Center Aerospace Communication Systems Technical Support (ACSTS) contract NNC05CA85C, Task 7: New ATM Requirements-Future Communications, C-Band and L-Band Communications Standard Development and was based on direction provided by FAA project-level agreements for New ATM Requirements-Future Communications. Task 7 included two subtasks. Subtask 7-1 addressed C-band (5091- to 5150-MHz) airport surface data communications standards development, systems engineering, test bed and prototype development, and tests and demonstrations to establish operational capability for the Aeronautical Mobile Airport Communications System (AeroMACS). Subtask 7-2 focused on systems engineering and development support of the L-band digital aeronautical communications system (L-DACS). Subtask 7-1 consisted of two phases. Phase I included development of AeroMACS concepts of use, requirements, architecture, and initial high-level safety risk assessment. Phase II builds on Phase I results and is presented in two volumes. Volume I (this document) is devoted to concepts of use, system requirements, and architecture, including AeroMACS design considerations. Volume II describes an AeroMACS prototype evaluation and presents final AeroMACS recommendations. This report also describes airport categorization and channelization methodologies. The purposes of the airport categorization task were (1) to facilitate initial AeroMACS architecture designs and enable budgetary projections by creating a set of airport categories based on common airport characteristics and design objectives, and (2) to offer high-level guidance to potential AeroMACS technology and policy development sponsors and service providers. A channelization plan methodology was developed because a common global methodology is needed to assure seamless interoperability among diverse AeroMACS services potentially supplied by multiple service providers.

Resting heart rate and the incidence and progression of valvular calcium: The Multi-Ethnic Study of Atherosclerosis (MESA).

PubMed

Amoakwa, Kojo; Fashanu, Oluwaseun E; Tibuakuu, Martin; Zhao, Di; Guallar, Eliseo; Whelton, Seamus P; O'Neal, Wesley T; Post, Wendy S; Budoff, Matthew J; Michos, Erin D

2018-06-01

Left-sided valvular calcification is associated with cardiovascular disease (CVD) morbidity and mortality. Resting heart rate (RHR) may influence valvular calcium progression through shear stress. Whether RHR, an established CVD risk factor, is associated with valvular calcium progression is unknown. We assessed whether RHR predicts incidence and progression of mitral annular calcium (MAC) and aortic valve calcium (AVC) in a community-based cohort free of CVD at baseline. RHR was obtained from baseline electrocardiograms of 5498 MESA participants. MAC and AVC were quantified using Agatston scoring from cardiac computed tomography scans obtained at baseline and at a second examination during follow-up. We examined associations of RHR with incident MAC/AVC and annual change in MAC/AVC scores, after adjusting for demographics, CVD risk factors, physical activity, and atrioventricular nodal blocker use. At baseline, participants had mean age of 62 ± 10 years and mean RHR of 63 ± 10 bpm; 12.3% and 8.9% had prevalent AVC and MAC, respectively. Over a median of 2.3 years, 4.1% and 4.5% developed incident AVC and MAC, respectively. Each 10 bpm higher RHR was significantly associated with incident MAC [Risk Ratio 1.17 (95% CI 1.03-1.34)], but not incident AVC. However, RHR was associated with AVC progression [β = 1.62 (0.45-2.80) Agatston units/year for every 10 bpm increment], but not MAC progression. Higher RHR was associated with MAC incidence and AVC progression, independent of traditional CVD risk factors. Future studies are needed to determine whether modification of RHR through lifestyle or pharmacologic interventions can reduce valvular calcium incidence or progression. Copyright © 2018 Elsevier B.V. All rights reserved.

Moringa isothiocyanate complexed with α-cyclodextrin: a new perspective in neuroblastoma treatment.

PubMed

Giacoppo, Sabrina; Iori, Renato; Rollin, Patrick; Bramanti, Placido; Mazzon, Emanuela

2017-07-14

Several lines of evidence suggest the consume of natural products for cancer prevention or treatment. In particular, isothiocyanates (ITCs) exerting anti-cancer properties, have received great interest as potential chemotherapeutic agents. This study was designed to assess the anti-proliferative activities of a new preparation of Moringa oleifera-derived 4-(α-L-rhamnopyranosyloxy)benzyl ITC (moringin) complexed with alpha-cyclodextrin (moringin + α-CD; MAC) on SH-SY5Y human neuroblastoma cells. This new formulation arises in the attempt to overcome the poor solubility and stability of moringin alone in aqueous media. SH-SY5Y cells were cultured and exposed to increasing concentrations of MAC (1.0, 2.5 and 5.0 μg). Cell proliferation was examined by MTT and cell count assays. The cytotoxic activity of the MAC complex was assessed by lactate dehydrogenase (LDH) assay and trypan blue exclusion test. In addition, western blotting analyses for the main apoptosis-related proteins were performed. Treatment of SH-SY5Y cells with the MAC complex reduced cell growth in concentration dependent manner. Specifically, MAC exhibited a potent action in inhibiting the PI3K/Akt/mTOR pathway, whose aberrant activation was found in many types of cancer. MAC was also found to induce the nuclear factor-κB (NF-κB) p65 activation by phosphorylation and its translocation into the nucleus. Moreover, treatment with MAC was able to down-regulate MAPK pathway (results focused on JNK and p38 expression). Finally, MAC was found to trigger apoptotic death pathway (based on expression levels of cleaved-caspase 3, Bax/Bcl-2 balance, p53 and p21). These findings suggest that use of MAC complex may open novel perspectives to improve the poor prognosis of patients with neuroblastoma.

Electromyographic activation reveals cortical and sub-cortical dissociation during emergence from general anesthesia.

PubMed

Hight, Darren F; Voss, Logan J; García, Paul S; Sleigh, Jamie W

2017-08-01

During emergence from anesthesia patients regain their muscle tone (EMG). In a typical population of surgical patients the actual volatile gas anesthetic concentrations in the brain (C e MAC) at which EMG activation occurs remains unknown, as is whether EMG activation at higher C e MACs is correlated with subsequent severe pain, or with cortical activation. Electroencephalographic (EEG) and EMG activity was recorded from the forehead of 273 patients emerging from general anesthesia following surgery. We determined C e MAC at time of EMG activation and at return of consciousness. Pain was assessed immediately after return of consciousness using an 11 point numerical rating scale. The onset of EMG activation during emergence was associated with neither discernible muscle movement nor with the presence of exogenous stimulation in half the patients. EMG activation could be modelled as two distinct processes; termed high- and low-C e MAC (occurring higher or lower than 0.07 C e MAC). Low-C e MAC activation was typically associated with simultaneous EMG activation and consciousness, and the presence of a laryngeal mask. In contrast, high-C e MAC EMG activation occurred independently of return of consciousness, and was not associated with severe post-operative pain, but was more common in the presence of an endotracheal tube. Patients emerging from general anesthesia with an endotracheal tube in place are more likely to have an EMG activation at higher C e MAC concentrations. These activations are not associated with subsequent high-pain, nor with cortical arousal, as evidenced by continuing delta waves in the EEG. Conversely, patients emerging from general anesthesia with a laryngeal mask demonstrate marked neural inertia-EMG activation occurs at a low C e MAC, and is closely temporally associated with return of consciousness.

Xenon neurotoxicity in rat hippocampal slice cultures is similar to isoflurane and sevoflurane.

PubMed

Brosnan, Heather; Bickler, Philip E

2013-08-01

Anesthetic neurotoxicity in the developing brain of rodents and primates has raised concern. Xenon may be a nonneurotoxic alternative to halogenated anesthetics, but its toxicity has only been studied at low concentrations, where neuroprotective effects predominate in animal models. An equipotent comparison of xenon and halogenated anesthetics with respect to neurotoxicity in developing neurons has not been made. Organotypic hippocampal cultures from 7-day-old rats were exposed to 0.75, 1, and 2 minimum alveolar concentrations (MAC) partial pressures (60% xenon at 1.2, 2.67, and 3.67 atm; isoflurane at 1.4, 1.9, and 3.8%; and sevoflurane at 3.4 and 6.8%) for 6 h, at atmospheric pressure or in a pressure chamber. Cell death was assessed 24 h later with fluorojade and fluorescent dye exclusion techniques. Xenon caused death of hippocampal neurons in CA1, CA3, and dentate regions after 1 and 2 MAC exposures, but not at 0.75 MAC. At 1 MAC, xenon increased cell death 40% above baseline (P < 0.01; ANOVA with Dunnett test). Both isoflurane and sevoflurane increased neuron death at 1 but not 2 MAC. At 1 MAC, the increase in cell death compared with controls was 63% with isoflurane and 90% with sevoflurane (both P < 0.001). Pretreatment of cultures with isoflurane (0.75 MAC) reduced neuron death after 1 MAC xenon, isoflurane, and sevoflurane. Xenon causes neuronal cell death in an in vitro model of the developing rodent brain at 1 MAC, as does isoflurane and sevoflurane at similarly potent concentrations. Preconditioning with a subtoxic dose of isoflurane eliminates this toxicity.

Operational effectiveness of a Multiple Aquila Control System (MACS)

NASA Technical Reports Server (NTRS)

Brown, R. W.; Flynn, J. D.; Frey, M. R.

1983-01-01

The operational effectiveness of a multiple aquila control system (MACS) was examined under a variety of remotely piloted vehicle (RPV) mission configurations. The set of assumptions and inputs used to form the rules under which a computerized simulation of MACS was run is given. The characteristics that are to govern MACS operations include: the battlefield environment that generates the requests for RPV missions, operating time-lines of the RPV-peculiar equipment, maintenance requirements, and vulnerability to enemy fire. The number of RPV missions and the number of operation days are discussed. Command, control, and communication data rates are estimated by determining how many messages are passed and what information is necessary in them to support ground coordination between MACS sections.

Rhetorical, Metacognitive, and Cognitive Strategies in Teacher Candidates' Essay Writing

ERIC Educational Resources Information Center

Diaz Larenas, Claudio; Ramos Leiva, Lucía; Ortiz Navarrete, Mabel

2017-01-01

This paper reports on a study about the rhetoric, metacognitive, and cognitive strategies pre-service teachers use before and after a process-based writing intervention when completing an argumentative essay. The data were collected through two think-aloud protocols while 21 Chilean English as a foreign language pre-service teachers completed an…

Think Aloud: Using Cognitive Interviewing to Validate the PISA Assessment of Student Self-Efficacy in Mathematics

ERIC Educational Resources Information Center

Pepper, David; Hodgen, Jeremy; Lamesoo, Katri; Kõiv, Pille; Tolboom, Jos

2018-01-01

Cognitive interviewing (CI) provides a method of systematically collecting validity evidence of response processes for questionnaire items. CI involves a range of techniques for prompting individuals to verbalise their responses to items. One such technique is concurrent verbalisation, as developed in Think Aloud Protocol (TAP). This article…

Validating Cognitive Models of Task Performance in Algebra on the SAT®. Research Report No. 2009-3

ERIC Educational Resources Information Center

Gierl, Mark J.; Leighton, Jacqueline P.; Wang, Changjiang; Zhou, Jiawen; Gokiert, Rebecca; Tan, Adele

2009-01-01

The purpose of the study is to present research focused on validating the four algebra cognitive models in Gierl, Wang, et al., using student response data collected with protocol analysis methods to evaluate the knowledge structures and processing skills used by a sample of SAT test takers.

U.S. Army Research Institute Program in Basic Research-FY 2010

DTIC Science & Technology

2010-11-01

2007). Do learning protocols support learning strategies and outcomes? The role of cognitive and metacognitive prompts. Learning and Instruction ...73 Achievement in Complex Learning Environments as a Function of Information Processing Ability ...Development and Validation of a Situational Judgment Test to Predict Attrition Incrementally Over General Cognitive Ability and a Forced-Choice

Assessing Personal Constructs of Adolescents with Autism Spectrum Disorder: A Person-Centered Measure of Social Cognition

ERIC Educational Resources Information Center

Hess, Sean; Self, Trisha; DiLollo, Anthony

2018-01-01

Many protocols assessing social communication skills of adolescents with autism spectrum disorder (ASD) are based on behavioral observations. It has been suggested, however, that social cognition encompasses processes underlying observable behaviors. Such processes include personal constructs, which can be assessed using repertory grids. Personal…

Assessment of strategic processing during narrative comprehension in individuals with mild cognitive impairment.

PubMed

Schmitter-Edgecombe, Maureen; Creamer, Scott

2010-07-01

A think-aloud protocol was used to examine the strategies used by individuals with mild cognitive impairment (MCI) during text comprehension. Twenty-three participants with MCI and 23 cognitively healthy older adults (OA) read narratives, pausing to verbalize their thoughts after each sentence. The verbal protocol analysis developed by Trabasso and Magliano (1996) was then used to code participants' utterances into inferential and non-inferential statements; inferential statements were further coded to identify the memory operation used in their generation. Compared with OA controls, the MCI participants showed poorer story comprehension and produced fewer inferences. The MCI participants were also less skilled at providing explanations of story events and in using prior text information to support inference generation. Poorer text comprehension was associated with poorer verbal memory abilities and poorer use of prior text events when producing inferential statements. The results suggest that the memory difficulties of the MCI group may be an important cognitive factor interfering with their ability to integrate narrative events through the use of inferences and to form a global coherence to support text comprehension.

Acoustical transmission-line model of the middle-ear cavities and mastoid air cells.

PubMed

Keefe, Douglas H

2015-04-01

An acoustical transmission line model of the middle-ear cavities and mastoid air cell system (MACS) was constructed for the adult human middle ear with normal function. The air-filled cavities comprised the tympanic cavity, aditus, antrum, and MACS. A binary symmetrical airway branching model of the MACS was constructed using an optimization procedure to match the average total volume and surface area of human temporal bones. The acoustical input impedance of the MACS was calculated using a recursive procedure, and used to predict the input impedance of the middle-ear cavities at the location of the tympanic membrane. The model also calculated the ratio of the acoustical pressure in the antrum to the pressure in the middle-ear cavities at the location of the tympanic membrane. The predicted responses were sensitive to the magnitude of the viscothermal losses within the MACS. These predicted input impedance and pressure ratio functions explained the presence of multiple resonances reported in published data, which were not explained by existing MACS models.

Low-temperature MIR to submillimeter mass absorption coefficient of interstellar dust analogues. II. Mg and Fe-rich amorphous silicates

NASA Astrophysics Data System (ADS)

Demyk, K.; Meny, C.; Leroux, H.; Depecker, C.; Brubach, J.-B.; Roy, P.; Nayral, C.; Ojo, W.-S.; Delpech, F.

2017-10-01

Context. To model the cold dust emission observed in the diffuse interstellar medium, in dense molecular clouds or in cold clumps that could eventually form new stars, it is mandatory to know the physical and spectroscopic properties of this dust and to understand its emission. Aims: This work is a continuation of previous studies aiming at providing astronomers with spectroscopic data of realistic cosmic dust analogues for the interpretation of observations. The aim of the present work is to extend the range of studied analogues to iron-rich silicate dust analogues. Methods: Ferromagnesium amorphous silicate dust analogues were produced by a sol-gel method with a mean composition close to Mg1-xFexSiO3 with x = 0.1, 0.2, 0.3, 0.4. Part of each sample was annealed at 500 °C for two hours in a reducing atmosphere to modify the oxidation state of iron. We have measured the mass absorption coefficient (MAC) of these eight ferromagnesium amorphous silicate dust analogues in the spectral domain 30-1000 μm for grain temperature in the range 10-300 K and at room temperature in the 5-40 μm range. Results: The MAC of ferromagnesium samples behaves in the same way as the MAC of pure Mg-rich amorphous silicate samples. In the 30-300 K range, the MAC increases with increasing grain temperature whereas in the range 10-30 K, we do not see any change of the MAC. The MAC cannot be described by a single power law in λ- β. The MAC of the samples does not show any clear trend with the iron content. However the annealing process has, on average, an effect on the MAC that we explain by the evolution of the structure of the samples induced by the processing. The MAC of all the samples is much higher than the MAC calculated by dust models. Conclusions: The complex behavior of the MAC of amorphous silicates with wavelength and temperature is observed whatever the exact silicate composition (Mg vs. Fe amount). It is a universal characteristic of amorphous materials, and therefore of amorphous cosmic silicates, that should be taken into account in astronomical modeling. The enhanced MAC of the measured samples compared to the MAC calculated for cosmic dust model implies that dust masses are overestimated by the models. The tabulated mass absorption coefficients are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/606/A50

Cognitive impairment and PD patients' capacity to consent to research

PubMed Central

Cary, Mark; Moelter, Stephen T.; Siderowf, Andrew; Sullo, Elizabeth; Xie, Sharon; Weintraub, Daniel

2013-01-01

Objective: To examine how cognitive impairment affects Parkinson disease (PD) patients' research consent capacity. Methods: A cross-sectional study of 90 patients with PD, divided using Mattis Dementia Rating Scale–2 scores into 3 groups of 30 (normal, borderline, and impaired), and 30 neurologically normal older adults completed 2 capacity interviews (an early-phase randomized and controlled drug trial and a sham-controlled surgical implantation of genetic tissue) using the MacArthur Competence Assessment Tool for Clinical Research. Expert clinicians used the interviews to classify the patients as either capable or not capable of providing their own informed consent. These judgments were compared with performance on the Montreal Cognitive Assessment (MoCA) and the Mini-Mental State Examination (MMSE). Results: Cognitively normal PD patients typically scored well on the capacity measures. In contrast, patients with impaired cognition were not capable of providing their own informed consent: 17% (5/30) on the drug trial and 3% (1/30) on the surgery trial were judged capable. Patients with borderline impairment showed adequate performance on measures of appreciation and reasoning, but impaired performance on understanding the drug trial compared with normal controls and normal PD patients, and on understanding the surgery trial compared with normal controls. Sixty-seven percent (20/30) on the drug trial and 57% (17/30) on the surgery trial were judged capable of consent. Receiver operating characteristic analyses showed that the MMSE and MoCA could detect the likelihood of impaired capacity, with the MoCA demonstrating greater sensitivity. Conclusions: PD patients with borderline cognitive impairment have impairments in their decisional capacity. The MoCA may be useful to identify the patients at risk of impaired capacity. PMID:23892706

Spectroscopic investigation of the interaction of water-soluble azocalix[4]arenes with bovine serum albumin.

PubMed

Fan, Ping; Wan, Lu; Shang, Yunshan; Wang, Jun; Liu, Yulong; Sun, Xiaoyu; Chen, Chen

2015-02-01

In this work, three hydrosoluble azocalix[4]arene derivatives, 5-(o-methylphenylazo)-25,26,27-tris(carboxymethoxy)-28-hydroxycalix[4]arene (o-MAC-Calix), 5-(m-methylphenylazo)-25,26,27-tris(carboxymethoxy)-28-hydroxycalix[4]arene (m-MAC-Calix) and 5-(p-methylphenylazo)-25,26,27-tris(carboxymethoxy)-28-hydroxycalix[4]arene (p-MAC-Calix) were synthesized. Their structures were characterized by infrared spectrum (IR), nuclear magnetic resonance spectrum (1H NMR and 13C NMR) and mass spectrum (MS). The interactions between these compounds and bovine serum albumin (BSA) were studied by fluorescence spectroscopy, UV-vis spectrophotometry and circular dichroic spectroscopy. According to experimental results, three azocalix[4]arene derivatives can efficiently bind to BSA molecules and the o-MAC-Calix displays more efficient interactions with BSA molecules than m-MAC-Calix and p-MAC-Calix. Molecular docking showed that the o-MAC-Calix was embedded in the hydrophobic cavity of helical structure of BSA molecular and the tryptophan (Trp) residue of BSA molecular had strong interaction with o-MAC-Calix. The fluorescence quenching of BSA caused by azocalix[4]arene derivatives is attributed to the static quenching process. In addition, the synchronous fluorescence spectroscopy indicates that these azocalix[4]arene derivatives are more accessible to Trp residues of BSA molecules than the tyrosine (Tyr) residues. The circular dichroic spectroscopy further verified the binding of azocalix[4]arene derivatives and BSA. Copyright © 2014 Elsevier Inc. All rights reserved.

Median effective dose of isoflurane, sevoflurane, and desflurane in green iguanas.

PubMed

Barter, Linda S; Hawkins, Michelle G; Brosnan, Robert J; Antognini, Joseph F; Pypendop, Bruno H

2006-03-01

To determine the median effective dose (ED(50); equivalent to the minimum alveolar concentration [MAC]) of isoflurane, sevoflurane, and desflurane for anesthesia in iguanas. 6 healthy adult green iguanas. In unmedicated iguanas, anesthesia was induced and maintained with each of the 3 volatile drugs administered on separate days according to a Latin square design. Iguanas were endotracheally intubated, mechanically ventilated, and instrumented for cardiovascular and respiratory measurements. During each period of anesthesia, MAC was determined in triplicate. The mean value of 2 consecutive expired anesthetic concentrations, 1 that just permitted and 1 that just prevented gross purposeful movement in response to supramaximal electrical stimulus, and that were not different by more than 15%, was deemed the MAC. Mean +/- SD values for the third MAC determination for isoflurane, sevoflurane, and desflurane were 1.8 +/- 0.3%, 3.1 +/- 1.0%, and 8.9 +/- 2.1% of atmospheric pressure, respectively. The MAC for all inhaled agents was, on average, 22% greater for the first measurement than for the third measurement. Over time, MACs decreased for all 3 agents. Final MAC measurements were similar to values reported for other species. The decrease in MACs over time may be at least partly explained by limitations of anesthetic uptake and distribution imposed by the reptilian cardiorespiratory system. Hence, for a constant end-tidal anesthetic concentration in an iguana, the plane of anesthesia may deepen over time, which could contribute to increased morbidity during prolonged procedures.

Matrix-assisted cocrystallization (MAC) simultaneous production and formulation of pharmaceutical cocrystals by hot-melt extrusion.

PubMed

Boksa, Kevin; Otte, Andrew; Pinal, Rodolfo

2014-09-01

A novel method for the simultaneous production and formulation of pharmaceutical cocrystals, matrix-assisted cocrystallization (MAC), is presented. Hot-melt extrusion (HME) is used to create cocrystals by coprocessing the drug and coformer in the presence of a matrix material. Carbamazepine (CBZ), nicotinamide (NCT), and Soluplus were used as a model drug, coformer, and matrix, respectively. The MAC product containing 80:20 (w/w) cocrystal:matrix was characterized by differential scanning calorimetry, Fourier transform infrared spectroscopy, and powder X-ray diffraction. A partial least squares (PLS) regression model was developed for quantifying the efficiency of cocrystal formation. The MAC product was estimated to be 78% (w/w) cocrystal (theoretical 80%), with approximately 0.3% mixture of free (unreacted) CBZ and NCT, and 21.6% Soluplus (theoretical 20%) with the PLS model. A physical mixture (PM) of a reference cocrystal (RCC), prepared by precipitation from solution, and Soluplus resulted in faster dissolution relative to the pure RCC. However, the MAC product with the exact same composition resulted in considerably faster dissolution and higher maximum concentration (∼five-fold) than those of the PM. The MAC product consists of high-quality cocrystals embedded in a matrix. The processing aspect of MAC plays a major role on the faster dissolution observed. The MAC approach offers a scalable process, suitable for the continuous manufacturing and formulation of pharmaceutical cocrystals. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.

Assessment of parental decision-making in neonatal cardiac research: a pilot study.

PubMed

Nathan, Aruna T; Hoehn, K Sarah; Ittenbach, Richard F; Gaynor, J William; Nicolson, Susan; Wernovsky, Gil; Nelson, Robert M

2010-02-01

To assess parental permission for a neonate's research participation using the MacArthur competence assessment tool for clinical research (MacCAT-CR), specifically testing the components of understanding, appreciation, reasoning and choice. Quantitative interviews using study-specific MacCAT-CR tools. Parents of critically ill newborns would produce comparable MacCAT-CR scores to healthy adult controls despite the emotional stress of an infant with critical heart disease or the urgency of surgery. Parents of infants diagnosed prenatally would have higher MacCAT-CR scores than parents of infants diagnosed postnatally. There would be no difference in MacCAT-CR scores between parents with respect to gender or whether they did or did not permit research participation. Parents of neonates undergoing cardiac surgery who had made decisions about research participation before their neonate's surgery. The MacCAT-CR. 35 parents (18 mothers; 17 fathers) of 24 neonates completed 55 interviews for one or more of three studies. Total scores: magnetic resonance imaging (mean 36.6, SD 7.71), genetics (mean 38.8, SD 3.44), heart rate variability (mean 37.7, SD 3.30). Parents generally scored higher than published subject populations and were comparable to published control populations with some exceptions. The MacCAT-CR can be used to assess parental permission for neonatal research participation. Despite the stress of a critically ill neonate requiring surgery, parents were able to understand study-specific information and make informed decisions to permit their neonate's participation.

Neurofeedback as a form of cognitive rehabilitation therapy following stroke: A systematic review

PubMed Central

Tibbles, Alana; Topolovec-Vranic, Jane

2017-01-01

Neurofeedback therapy (NFT) has been used within a number of populations however it has not been applied or thoroughly examined as a form of cognitive rehabilitation within a stroke population. Objectives for this systematic review included: i) identifying how NFT is utilized to treat cognitive deficits following stroke, ii) examining the strength and quality of evidence to support the use of NFT as a form of cognitive rehabilitation therapy (CRT) and iii) providing recommendations for future investigations. Searches were conducted using OVID (Medline, Health Star, Embase + Embase Classic) and PubMed databases. Additional searches were completed using the Cochrane Reviews library database, Google Scholar, the University of Toronto online library catalogue, ClinicalTrials.gov website and select journals. Searches were completed Feb/March 2015 and updated in June/July/Aug 2015. Eight studies were eligible for inclusion in this review. Studies were eligible for inclusion if they: i) were specific to a stroke population, ii) delivered CRT via a NFT protocol, iii) included participants who were affected by a cognitive deficit(s) following stroke (i.e. memory loss, loss of executive function, speech impairment etc.). NFT protocols were highly specific and varied within each study. The majority of studies identified improvements in participant cognitive deficits following the initiation of therapy. Reviewers assessed study quality using the Downs and Black Checklist for Measuring Study Quality tool; limited study quality and strength of evidence restricted generalizability of conclusions regarding the use of this therapy to the greater stroke population. Progression in this field requires further inquiry to strengthen methodology quality and study design. Future investigations should aim to standardize NFT protocols in an effort to understand the dose-response relationship between NFT and improvements in functional outcome. Future investigations should also place a large emphasis on long-term participant follow-up. PMID:28510578

Neurofeedback as a form of cognitive rehabilitation therapy following stroke: A systematic review.

PubMed

Renton, Tian; Tibbles, Alana; Topolovec-Vranic, Jane

2017-01-01

Neurofeedback therapy (NFT) has been used within a number of populations however it has not been applied or thoroughly examined as a form of cognitive rehabilitation within a stroke population. Objectives for this systematic review included: i) identifying how NFT is utilized to treat cognitive deficits following stroke, ii) examining the strength and quality of evidence to support the use of NFT as a form of cognitive rehabilitation therapy (CRT) and iii) providing recommendations for future investigations. Searches were conducted using OVID (Medline, Health Star, Embase + Embase Classic) and PubMed databases. Additional searches were completed using the Cochrane Reviews library database, Google Scholar, the University of Toronto online library catalogue, ClinicalTrials.gov website and select journals. Searches were completed Feb/March 2015 and updated in June/July/Aug 2015. Eight studies were eligible for inclusion in this review. Studies were eligible for inclusion if they: i) were specific to a stroke population, ii) delivered CRT via a NFT protocol, iii) included participants who were affected by a cognitive deficit(s) following stroke (i.e. memory loss, loss of executive function, speech impairment etc.). NFT protocols were highly specific and varied within each study. The majority of studies identified improvements in participant cognitive deficits following the initiation of therapy. Reviewers assessed study quality using the Downs and Black Checklist for Measuring Study Quality tool; limited study quality and strength of evidence restricted generalizability of conclusions regarding the use of this therapy to the greater stroke population. Progression in this field requires further inquiry to strengthen methodology quality and study design. Future investigations should aim to standardize NFT protocols in an effort to understand the dose-response relationship between NFT and improvements in functional outcome. Future investigations should also place a large emphasis on long-term participant follow-up.

MacMouse. Developing Preschool Readiness Concepts and Skills with HyperCard and MacRecorder.

ERIC Educational Resources Information Center

Fitterman, L. Jeffrey

Through developments with the use of the "Apple Macintosh" computer, "HyperCard," and "MacRecorder," children in preschool handicapped programs are now capable of participating in appropriate computerized learning experiences. "HyperCard" allows educators to produce their own computerized instructional…