Sample records for cellular communication system

  1. Capacity on wireless quantum cellular communication system

    NASA Astrophysics Data System (ADS)

    Zhou, Xiang-Zhen; Yu, Xu-Tao; Zhang, Zai-Chen

    2018-03-01

    Quantum technology is making excellent prospects in future communication networks. Entanglement generation and purification are two major components in quantum networks. Combining these two techniques with classical cellular mobile communication, we proposed a novel wireless quantum cellular(WQC) communication system which is possible to realize commercial mobile quantum communication. In this paper, the architecture and network topology of WQC communication system are discussed, the mathematical model of WQC system is extracted and the serving capacity, indicating the ability to serve customers, is defined and calculated under certain circumstances.

  2. A Study on Cognitive Radio Coexisting with Cellular Systems

    NASA Astrophysics Data System (ADS)

    Tandai, Tomoya; Horiguchi, Tomoya; Deguchi, Noritaka; Tomizawa, Takeshi; Tomioka, Tazuko

    Cognitive Radios (CRs) are expected to perform more significant role in the view of efficient utilization of the spectrum resources in the future wireless communication networks. In this paper, a cognitive radio coexisting with cellular systems is proposed. In the case that a cellular system adopts Frequency Division Duplex (FDD) as a multiplexing scheme, the proposed CR terminals communicate in local area on uplink channels of the cellular system with transmission powers that don't interfere with base stations of the cellular system. Alternatively, in the case that a cellular system adopts Time Division Duplex (TDD), the CR terminals communicate on uplink slots of the cellular system. However if mobile terminals in the cellular system are near the CR network, uplink signals from the mobile terminals may interfere with the CR communications. In order to avoid interference from the mobile terminals, the CR terminal performs carrier sense during a beginning part of uplink slot, and only when the level of detected signal is below a threshold, then the CR terminal transmits a signal during the remained period of the uplink slot. In this paper, both the single carrier CR network that uses one frequency channel of the cellular system and the multicarrier CR network that uses multiple frequency channels of the cellular system are considered. The probabilities of successful CR communications, the average throughputs of the CR communications according to the positions of the CR network, and the interference levels from cognitive radio network to base stations of the cellular system are evaluated in the computer simulation then the effectiveness of the proposed network is clarified.

  3. 47 CFR 22.923 - Cellular system configuration.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 22.923 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.923 Cellular system configuration. Mobile stations communicate with and through base transmitters only. Base transmitters communicate with mobile stations...

  4. How Much Longer before It All Works: What Online Searchers Should Know about Wireless Data Communications.

    ERIC Educational Resources Information Center

    Bell, Steven J.

    1994-01-01

    Profiles the major wireless data communications (WDC) systems, provides an overview of how they work, and compares their communication features. Topics addressed include the market for wireless data; applications for WDC; wireless online searching; cellular data communication; packet radio; digital cellular; criteria for evaluating WDC systems;…

  5. MSAT and cellular hybrid networking

    NASA Astrophysics Data System (ADS)

    Baranowsky, Patrick W., II

    Westinghouse Electric Corporation is developing both the Communications Ground Segment and the Series 1000 Mobile Phone for American Mobile Satellite Corporation's (AMSC's) Mobile Satellite (MSAT) system. The success of the voice services portion of this system depends, to some extent, upon the interoperability of the cellular network and the satellite communication circuit switched communication channels. This paper will describe the set of user-selectable cellular interoperable modes (cellular first/satellite second, etc.) provided by the Mobile Phone and described how they are implemented with the ground segment. Topics including roaming registration and cellular-to-satellite 'seamless' call handoff will be discussed, along with the relevant Interim Standard IS-41 Revision B Cellular Radiotelecommunications Intersystem Operations and IOS-553 Mobile Station - Land Station Compatibility Specification.

  6. 47 CFR 90.672 - Unacceptable interference to non-cellular 800 MHz licensees from 800 MHz cellular systems or part...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... MHz licensees from 800 MHz cellular systems or part 22 Cellular Radiotelephone systems, and within the... COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES... licensees from 800 MHz cellular systems or part 22 Cellular Radiotelephone systems, and within the 900 MHz...

  7. 47 CFR 22.923 - Cellular system configuration.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Cellular system configuration. 22.923 Section 22.923 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.923 Cellular system configuration. Mobile stations...

  8. 47 CFR 22.923 - Cellular system configuration.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Cellular system configuration. 22.923 Section 22.923 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.923 Cellular system configuration. Mobile stations...

  9. 47 CFR 90.672 - Unacceptable interference to non-cellular 800 MHz licensees from 800 MHz cellular systems or part...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Unacceptable interference to non-cellular 800 MHz licensees from 800 MHz cellular systems or part 22 Cellular Radiotelephone systems, and within the 900 MHz Business/Industrial Land Transportation Pool. 90.672 Section 90.672 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY...

  10. Mobile communication devices causing interference in invasive and noninvasive ventilators.

    PubMed

    Dang, Bao P; Nel, Pierre R; Gjevre, John A

    2007-06-01

    The aim of this study was to assess if common mobile communication systems would cause significant interference on mechanical ventilation devices and at what distances would such interference occur. We tested all the invasive and noninvasive ventilatory devices used within our region. This consisted of 2 adult mechanical ventilators, 1 portable ventilator, 2 pediatric ventilators, and 2 noninvasive positive pressure ventilatory devices. We operated the mobile devices from the 2 cellular communication systems (digital) and 1 2-way radio system used in our province at varying distances from the ventilators and looked at any interference they created. We tested the 2-way radio system, which had a fixed operation power output of 3.0 watts, the Global Systems for Mobile Communication cellular system, which had a maximum power output of 2.0 watts and the Time Division Multiple Access cellular system, which had a maximum power output of 0.2 watts on our ventilators. The ventilators were ventilating a plastic lung at fixed settings. The mobile communication devices were tested at varying distances starting at zero meter from the ventilator and in all operation modes. The 2-way radio caused the most interference on some of the ventilators, but the maximum distance of interference was 1.0 m. The Global Systems for Mobile Communication system caused significant interference only at 0 m and minor interference at 0.5 m on only 1 ventilator. The Time Division Multiple Access system caused no interference at all. Significant interference consisted of a dramatic rise and fluctuation of the respiratory rate, pressure, and positive end-expiratory pressure of the ventilators with no normalization when the mobile device was removed. From our experiment on our ventilators with the communication systems used in our province, we conclude that mobile communication devices such as cellular phones and 2-way radios are safe and cause no interference unless operated at very close distances of less than 1 meter.

  11. Wireless teleradiology and fax using cellular phones and notebook PCs for instant access to consultants.

    PubMed

    Yamamoto, L G

    1995-03-01

    The feasibility of wireless portable teleradiology and facsimile (fax) transmission using a pocket cellular phone and a notebook computer to obtain immediate access to consultants at any location was studied. Modems specially designed for data and fax communication via cellular systems were employed to provide a data communication interface between the cellular phone and the notebook computer. Computed tomography (CT) scans, X-rays, and electrocardiograms (ECGs) were transmitted to a wireless unit to measure performance characteristics. Data transmission rates ranged from 520 to 1100 bytes per second. Typical image transmission times ranged from 1 to 10 minutes; however, using joint photographic experts group or fractal image compression methods would shorten typical transmission times to less than one minute. This study showed that wireless teleradiology and fax over cellular communication systems are feasible with current technology. Routine immediate cellular faxing of ECGs to cardiologists may expedite thrombolytic therapy decisions in questionable cases. Routine immediate teleradiology of CT scans may reduce operation room preparation times in severe head trauma.

  12. [Cell phone communication: hygienic characteristics, biological action, standardization (a review)].

    PubMed

    Gudina, M V; Volkotrub, L P

    2010-01-01

    The paper considers the topical issues concerning the functioning of the cellular communication system. It provides the hygienic characteristics of its individual elements. The factors influencing the size of an electromagnetic field generated by mobile phones are stated. Research data on the impact of electromagnetic radiation from a mobile phone on users' health are reviewed. The pivots of present-day Russian hygienic rating regarding the permissible exposures to nonionizing electromagnetic energy generated by the elements of the cellular communication system are identified.

  13. Performance Comparison of Orthogonal and Quasi-orthogonal Codes in Quasi-Synchronous Cellular CDMA Communication

    NASA Astrophysics Data System (ADS)

    Jos, Sujit; Kumar, Preetam; Chakrabarti, Saswat

    Orthogonal and quasi-orthogonal codes are integral part of any DS-CDMA based cellular systems. Orthogonal codes are ideal for use in perfectly synchronous scenario like downlink cellular communication. Quasi-orthogonal codes are preferred over orthogonal codes in the uplink communication where perfect synchronization cannot be achieved. In this paper, we attempt to compare orthogonal and quasi-orthogonal codes in presence of timing synchronization error. This will give insight into the synchronization demands in DS-CDMA systems employing the two classes of sequences. The synchronization error considered is smaller than chip duration. Monte-Carlo simulations have been carried out to verify the analytical and numerical results.

  14. NASA Lunar Base Wireless System Propagation Analysis

    NASA Technical Reports Server (NTRS)

    Hwu, Shian U.; Upanavage, Matthew; Sham, Catherine C.

    2007-01-01

    There have been many radio wave propagation studies using both experimental and theoretical techniques over the recent years. However, most of studies have been in support of commercial cellular phone wireless applications. The signal frequencies are mostly at the commercial cellular and Personal Communications Service bands. The antenna configurations are mostly one on a high tower and one near the ground to simulate communications between a cellular base station and a mobile unit. There are great interests in wireless communication and sensor systems for NASA lunar missions because of the emerging importance of establishing permanent lunar human exploration bases. Because of the specific lunar terrain geometries and RF frequencies of interest to the NASA missions, much of the published literature for the commercial cellular and PCS bands of 900 and 1800 MHz may not be directly applicable to the lunar base wireless system and environment. There are various communication and sensor configurations required to support all elements of a lunar base. For example, the communications between astronauts, between astronauts and the lunar vehicles, between lunar vehicles and satellites on the lunar orbits. There are also various wireless sensor systems among scientific, experimental sensors and data collection ground stations. This presentation illustrates the propagation analysis of the lunar wireless communication and sensor systems taking into account the three dimensional terrain multipath effects. It is observed that the propagation characteristics are significantly affected by the presence of the lunar terrain. The obtained results indicate the lunar surface material, terrain geometry and antenna location are the important factors affecting the propagation characteristics of the lunar wireless systems. The path loss can be much more severe than the free space propagation and is greatly affected by the antenna height, surface material and operating frequency. The results from this paper are important for the lunar wireless system link margin analysis in order to determine the limits on the reliable communication range, achievable data rate and RF coverage performance at planned lunar base work sites.

  15. 47 CFR 27.2 - Permissible communications.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... bands. Operators in the 775-776 MHz and 805-806 MHz bands may not employ a cellular system architecture. A cellular system architecture is defined, for purposes of this part, as one that consists of many...

  16. 47 CFR 27.2 - Permissible communications.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... bands. Operators in the 775-776 MHz and 805-806 MHz bands may not employ a cellular system architecture. A cellular system architecture is defined, for purposes of this part, as one that consists of many...

  17. 47 CFR 27.2 - Permissible communications.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    .... Operators in the 775-776 MHz and 805-806 MHz bands may not employ a cellular system architecture. A cellular system architecture is defined, for purposes of this part, as one that consists of many small areas or...

  18. 47 CFR 27.2 - Permissible communications.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    .... Operators in the 775-776 MHz and 805-806 MHz bands may not employ a cellular system architecture. A cellular system architecture is defined, for purposes of this part, as one that consists of many small areas or...

  19. Tradeoff Analysis for Combat Service Support Wireless Communications Alternatives

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

    Burnette, John R.; Thibodeau, Christopher C.; Greitzer, Frank L.

    2002-02-28

    As the Army moves toward more mobile and agile forces and continued sustainment of numerous high-cost legacy logistics management systems, the requirement for wireless connectivity and a wireless network to supporting organizations has become ever more critical. There are currently several Army communications initiatives underway to resolve this wireless connectivity issue. However, to fully appreciate and understand the value of these initiatives, a Tradeoff Analysis is needed. The present study seeks to identify and assess solutions. The analysis identified issues that impede Interim Brigade Combat Team (IBCT) communication system integration and outlined core requirements for sharing of logistics data betweenmore » the field and Army battle command systems. Then, the analysis examined wireless communication alternatives as possible solutions for IBCT logistics communications problems. The current baseline system was compared with possible alternatives involving tactical radio systems, wireless/near term digital radio, cellular satellite, and third-generation (3G) wireless technologies. Cellular satellite and 3G wireless technologies offer clear advantages and should be considered for later IBCTs.« less

  20. Odyssey personal communications satellite system

    NASA Technical Reports Server (NTRS)

    Spitzer, Christopher J.

    1993-01-01

    The spectacular growth of cellular telephone networks has proved the demand for personal communications. Large regions of the world are too sparsely populated to be economically served by terrestrial cellular communications. Since satellites are well suited to this application, TRW filed with the FCC on May 31, 1993 for the Odyssey construction permit. Odyssey will provide high quality wireless communication services worldwide from satellites. These services will include: voice, data, paging, and messaging. Odyssey will be an economical approach to providing communications. A constellation of 12 satellites will be orbited in three, 55 deg. inclined planes at an altitude of 10,354 km to provide continuous coverage of designated regions. Two satellites will be visible anywhere in the world at all times. This dual visibility leads to high line-of-sight elevation angles, minimizing obstructions by terrain, trees and buildings. Each satellite generates a multibeam antenna pattern that divides its coverage area into a set of contiguous cells. The communications system employs spread spectrum CDMA on both the uplinks and downlinks. This signaling method permits band sharing with other systems and applications. Signal processing is accomplished on the ground at the satellite's 'Gateway' stations. The 'bent pipe' transponders accommodates different regional standards, as well as signaling changes over time. The low power Odyssey handset will be cellular compatible. Multipath fade protection is provided in the handset.

  1. 47 CFR 32.5003 - Cellular mobile revenue.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false Cellular mobile revenue. 32.5003 Section 32.5003 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES UNIFORM SYSTEM OF ACCOUNTS FOR TELECOMMUNICATIONS COMPANIES Instructions For Revenue Accounts § 32.5003 Cellular...

  2. 47 CFR 32.5003 - Cellular mobile revenue.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Cellular mobile revenue. 32.5003 Section 32.5003 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES UNIFORM SYSTEM OF ACCOUNTS FOR TELECOMMUNICATIONS COMPANIES Instructions For Revenue Accounts § 32.5003 Cellular...

  3. 47 CFR 22.927 - Responsibility for mobile stations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Section 22.927 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES.... Mobile stations that are subscribers in good standing to a cellular system, when receiving service from... receiving service through their cellular systems. Mobile stations that are subscribers in good standing to a...

  4. 47 CFR 22.927 - Responsibility for mobile stations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Section 22.927 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES.... Mobile stations that are subscribers in good standing to a cellular system, when receiving service from... receiving service through their cellular systems. Mobile stations that are subscribers in good standing to a...

  5. Airborne wireless communication systems, airborne communication methods, and communication methods

    DOEpatents

    Deaton, Juan D [Menan, ID; Schmitt, Michael J [Idaho Falls, ID; Jones, Warren F [Idaho Falls, ID

    2011-12-13

    An airborne wireless communication system includes circuitry configured to access information describing a configuration of a terrestrial wireless communication base station that has become disabled. The terrestrial base station is configured to implement wireless communication between wireless devices located within a geographical area and a network when the terrestrial base station is not disabled. The circuitry is further configured, based on the information, to configure the airborne station to have the configuration of the terrestrial base station. An airborne communication method includes answering a 911 call from a terrestrial cellular wireless phone using an airborne wireless communication system.

  6. Statewide Cellular Coverage Map

    DOT National Transportation Integrated Search

    2002-02-01

    The role of wireless communications in transportation is becoming increasingly important. Wireless communications are critical for many applications of Intelligent Transportation Systems (ITS) such as Automatic Vehicle Location (AVL) and Automated Co...

  7. Engineered cell-cell communication via DNA messaging

    PubMed Central

    2012-01-01

    Background Evolution has selected for organisms that benefit from genetically encoded cell-cell communication. Engineers have begun to repurpose elements of natural communication systems to realize programmed pattern formation and coordinate other population-level behaviors. However, existing engineered systems rely on system-specific small molecules to send molecular messages among cells. Thus, the information transmission capacity of current engineered biological communication systems is physically limited by specific biomolecules that are capable of sending only a single message, typically “regulate transcription.” Results We have engineered a cell-cell communication platform using bacteriophage M13 gene products to autonomously package and deliver heterologous DNA messages of varying lengths and encoded functions. We demonstrate the decoupling of messages from a common communication channel via the autonomous transmission of various arbitrary genetic messages. Further, we increase the range of engineered DNA messaging across semisolid media by linking message transmission or receipt to active cellular chemotaxis. Conclusions We demonstrate decoupling of a communication channel from message transmission within engineered biological systems via the autonomous targeted transduction of user-specified heterologous DNA messages. We also demonstrate that bacteriophage M13 particle production and message transduction occurs among chemotactic bacteria. We use chemotaxis to improve the range of DNA messaging, increasing both transmission distance and communication bit rates relative to existing small molecule-based communication systems. We postulate that integration of different engineered cell-cell communication platforms will allow for more complex spatial programming of dynamic cellular consortia. PMID:22958599

  8. Virtual target tracking (VTT) as applied to mobile satellite communication networks

    NASA Astrophysics Data System (ADS)

    Amoozegar, Farid

    1999-08-01

    Traditionally, target tracking has been used for aerospace applications, such as, tracking highly maneuvering targets in a cluttered environment for missile-to-target intercept scenarios. Although the speed and maneuvering capability of current aerospace targets demand more efficient algorithms, many complex techniques have already been proposed in the literature, which primarily cover the defense applications of tracking methods. On the other hand, the rapid growth of Global Communication Systems, Global Information Systems (GIS), and Global Positioning Systems (GPS) is creating new and more diverse challenges for multi-target tracking applications. Mobile communication and computing can very well appreciate a huge market for Cellular Communication and Tracking Devices (CCTD), which will be tracking networked devices at the cellular level. The objective of this paper is to introduce a new concept, i.e., Virtual Target Tracking (VTT) for commercial applications of multi-target tracking algorithms and techniques as applied to mobile satellite communication networks. It would be discussed how Virtual Target Tracking would bring more diversity to target tracking research.

  9. 47 CFR 22.877 - Unacceptable interference to Part 90 non-cellular 800 MHz licensees from commercial aviation air...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...-cellular 800 MHz licensees from commercial aviation air-ground systems. 22.877 Section 22.877 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Air-Ground Radiotelephone Service Commercial Aviation Air-Ground Systems § 22.877 Unacceptable interference...

  10. Requirements for a mobile communications satellite system. Volume 2: Technical report

    NASA Technical Reports Server (NTRS)

    Horstein, M.

    1983-01-01

    Three types of satellite aided mobile communications are considered for users in areas not served by (terrestrial) cellular radio systems. In system 1, mobile units are provided a direct satellite link to a gateway station, which serves as the interface to the terrestrial toll network. In system 2, a terrestrial radio link similar to those in cellular systems connects the mobile unit to a translator station; each translator relays the traffic from mobile units in its vicinity, via satellite, to the regional gateway. It is not feasible for system 2 to provide obiquitous coverage. Therefore, system 3 is introduced, in which the small percentage of users not within range of a translator are provided a direct satellite link as in system 1.

  11. Modems for emerging digital cellular-mobile radio system

    NASA Technical Reports Server (NTRS)

    Feher, Kamilo

    1991-01-01

    Digital modem techniques for emerging digital cellular telecommunications-mobile radio system applications are described and analyzed. In particular, theoretical performance, experimental results, principles of operation, and various architectures of pi/4-QPSK (pi/4-shifted coherent or differential QPSK) modems for second-generation US digital cellular radio system applications are presented. The spectral/power efficiency and performance of the pi/4-QPSK modems (American and Japanese digital cellular emerging standards) are studied and briefly compared to GMSK (Gaussian minimum-shift keying) modems (proposed for European DECT and GSM cellular standards). Improved filtering strategies and digital pilot-aided (digital channel sounding) techniques are also considered for pi/4-QPSK and other digital modems. These techniques could significantly improve the performance of digital cellular and other digital land mobile and satellite mobile radio systems. More spectrally efficient modem trends for future cellular/mobile (land mobile) and satellite communication systems applications are also highlighted.

  12. An Overview and Analysis of Mobile Internet Protocols in Cellular Environments.

    ERIC Educational Resources Information Center

    Chao, Han-Chieh

    2001-01-01

    Notes that cellular is the inevitable future architecture for the personal communication service system. Discusses the current cellular support based on Mobile Internet Protocol version 6 (Ipv6) and points out the shortfalls of using Mobile IP. Highlights protocols especially for mobile management schemes which can optimize a high-speed mobile…

  13. A Study of Chaos in Cellular Automata

    NASA Astrophysics Data System (ADS)

    Kamilya, Supreeti; Das, Sukanta

    This paper presents a study of chaos in one-dimensional cellular automata (CAs). The communication of information from one part of the system to another has been taken into consideration in this study. This communication is formalized as a binary relation over the set of cells. It is shown that this relation is an equivalence relation and all the cells form a single equivalence class when the cellular automaton (CA) is chaotic. However, the communication between two cells is sometimes blocked in some CAs by a subconfiguration which appears in between the cells during evolution. This blocking of communication by a subconfiguration has been analyzed in this paper with the help of de Bruijn graph. We identify two types of blocking — full and partial. Finally a parameter has been developed for the CAs. We show that the proposed parameter performs better than the existing parameters.

  14. Paracrine communication maximizes cellular response fidelity in wound signaling

    PubMed Central

    Handly, L Naomi; Pilko, Anna; Wollman, Roy

    2015-01-01

    Population averaging due to paracrine communication can arbitrarily reduce cellular response variability. Yet, variability is ubiquitously observed, suggesting limits to paracrine averaging. It remains unclear whether and how biological systems may be affected by such limits of paracrine signaling. To address this question, we quantify the signal and noise of Ca2+ and ERK spatial gradients in response to an in vitro wound within a novel microfluidics-based device. We find that while paracrine communication reduces gradient noise, it also reduces the gradient magnitude. Accordingly we predict the existence of a maximum gradient signal to noise ratio. Direct in vitro measurement of paracrine communication verifies these predictions and reveals that cells utilize optimal levels of paracrine signaling to maximize the accuracy of gradient-based positional information. Our results demonstrate the limits of population averaging and show the inherent tradeoff in utilizing paracrine communication to regulate cellular response fidelity. DOI: http://dx.doi.org/10.7554/eLife.09652.001 PMID:26448485

  15. Adaptive Antenna System for Both 4G LTE and 5G Cellular Systems

    NASA Astrophysics Data System (ADS)

    Henderson, Kendrick Q. T.

    Given the steep increase in the use of mobile communication systems, the current 4G/LTE (Long Term Evolution), cellular system will not be able to handle the increase in data. It is estimated that by 2020 the bandwidth requirements will be 10 times greater than what LTE can sustain. A new 5th generation (5G) communication system has been proposed to meet this demand. The physical layer or the antenna is the most critical part of any wireless communication systems as it is the interface between the free space medium and an electrical circuit. It sets the margin for almost all design parameters in the system such as the system noise and bandwidth. Several interactions of antennas have been proposed over the years for cellular services. These antennas are of various geometries, bandwidths, and radiation patterns with almost all having linear polarization. This thesis attempts to solve the multiple LTE antenna problem by creating a simple antenna that covers most of the LTE bands (850-2700 MHz) as well as introducing an antenna system at the 28 GHz 5G band. This allows for a greater educated hypothesis into what 5G can offer at the physical layer. The proposed concept will provide a solution to the co-existence problem of upcoming 5G wireless systems to be interoperable with existing 4G/LTE system.

  16. Downlink Multihop Transmission Technique for Asymmetric Traffic Accommodation in DS-CDMA/FDD Cellular Communications

    NASA Astrophysics Data System (ADS)

    Mori, Kazuo; Naito, Katsuhiro; Kobayashi, Hideo

    This paper proposes an asymmetric traffic accommodation scheme using a multihop transmission technique for CDMA/FDD cellular communication systems. The proposed scheme exploits the multihop transmission to downlink packet transmissions, which require the large transmission power at their single-hop transmissions, in order to increase the downlink capacity. In these multihop transmissions, vacant uplink band is used for the transmissions from relay stations to destination mobile stations, and this leads more capacity enhancement in the downlink communications. The relay route selection method and power control method for the multihop transmissions are also investigated in the proposed scheme. The proposed scheme is evaluated by computer simulation and the results show that the proposed scheme can achieve better system performance.

  17. Utilization of Concurrent Buffers to Facilitate Seamless Data Transition in Tactical Cellular Communications

    DTIC Science & Technology

    2015-09-01

    INTENTIONALLY LEFT BLANK xiii LIST OF ACRONYMS AND ABBREVIATIONS 2G 2nd Generation 3G 3rd Generation 3GPP 3rd Generation Partnership Project 4G 4th...System (UMTS) is the standard that governs 3rd Generation ( 3G ) migration of Global Services for Mobile (GSM) networks. It defines packet-based...network may assist or mitigate. 14. SUBJECT TERMS IEEE, 802.21, Media Independent Handover, mobile , communications, cyber, tactical, buffer, cellular

  18. 47 CFR 22.955 - Canadian condition.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Canadian condition. 22.955 Section 22.955 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES... the Department of Communications in Canada, authorizations for cellular systems within 72 kilometers...

  19. Direct cellular vs. indirect pager communication during orthopaedic surgical procedures: a prospective study.

    PubMed

    Ortega, Gil R; Taksali, Sudeep; Smart, Ryan; Baumgaertner, Michael R

    2009-01-01

    Cellular phone use within the hospital setting has increased as physicians, nurses, and ancillary staff incorporate wireless technologies in improving efficiencies, cost, and maintaining patient safety and high quality healthcare [11]. Through the use of wireless, cellular communication, an overall improvement in communication accuracy and efficiency between intraoperative orthopaedic surgeons and floor nurses may be achieved. Both communication types occurred while the surgeon was scrubbed in the operating room (OR). Indirect communication occurred when the pager call was answered by the OR circulating nurse with communication between the surgeon, circulating nurse, and floor nurse. Direct communication consisted of cell phone and Jabra Bluetooth BT200 wireless ear piece used by the surgeon. The surgeon answered the floor nurse's cellular call by phone ring-activated automatic answering. The study was conducted during scheduled orthopaedic procedures. An independent observer measured time variables with a stop-watch while orthopaedic nurses randomly called via pager or cell phone. The nurses asked for patient caregiver confirmation and answers to 30 different patient-care questions. Sixty trials were performed with 30 cell and 30 page communications. Direct cellular communication showed a better response rate than indirect page (Cell 100%, Page 73%). Indirect page communication allowed a 27% and 33% error rate with patient problem and surgeon solution communications, respectively. There were no reported communication errors while using direct wireless, cellular communication. When compared to page communications, cellular communications showed statistically significant improvements in mean time intervals in response time (Cell = 11s, Page = 211s), correct patient identification (Cell = 5s, Page = 172s), patient problem and solution time (Cell = 13s, Page = 189s), and total communication time (Cell = 32s, Page = 250s) (s = seconds, all P < 0.001). Floor nurse satisfaction ratings (dependent on communication times and/or difficulties) were improved with direct cellular communication (Cell = 29 excellent, Page = 11 excellent). Intraoperative case interruptions (defined as delaying surgical progress) were more frequent with indirect page communication (10 page v. 0 cell). Our study demonstrates that direct wireless communication may be used to improve intraoperative communication and enhance patient safety. Direct wireless, cellular intraoperative communication improves communication times, communication accuracy, communication satisfaction, and minimizes intraoperative case interruption. As a result of this study, we hope to maintain our transition to direct wireless, cellular intraoperative orthopaedic communication to reduce medical errors, improve patient care, and enhance both orthopaedic surgeon and nursing efficiencies.

  20. Remotely supported prehospital ultrasound: A feasibility study of real-time image transmission and expert guidance to aid diagnosis in remote and rural communities.

    PubMed

    Eadie, Leila; Mulhern, John; Regan, Luke; Mort, Alasdair; Shannon, Helen; Macaden, Ashish; Wilson, Philip

    2017-01-01

    Introduction Our aim is to expedite prehospital assessment of remote and rural patients using remotely-supported ultrasound and satellite/cellular communications. In this paradigm, paramedics are remotely-supported ultrasound operators, guided by hospital-based specialists, to record images before receiving diagnostic advice. Technology can support users in areas with little access to medical imaging and suboptimal communications coverage by connecting to multiple cellular networks and/or satellites to stream live ultrasound and audio-video. Methods An ambulance-based demonstrator system captured standard trauma and novel transcranial ultrasound scans from 10 healthy volunteers at 16 locations across the Scottish Highlands. Volunteers underwent brief scanning training before receiving expert guidance via the communications link. Ultrasound images were streamed with an audio/video feed to reviewers for interpretation. Two sessions were transmitted via satellite and 21 used cellular networks. Reviewers rated image and communication quality, and their utility for diagnosis. Transmission latency and bandwidth were recorded, and effects of scanner and reviewer experience were assessed. Results Appropriate views were provided in 94% of the simulated trauma scans. The mean upload rate was 835/150 kbps and mean latency was 114/2072 ms for cellular and satellite networks, respectively. Scanning experience had a significant impact on time to achieve a diagnostic image, and review of offline scans required significantly less time than live-streamed scans. Discussion This prehospital ultrasound system could facilitate early diagnosis and streamlining of treatment pathways for remote emergency patients, being particularly applicable in rural areas worldwide with poor communications infrastructure and extensive transport times.

  1. Anakoinosis: Communicative Reprogramming of Tumor Systems - for Rescuing from Chemorefractory Neoplasia.

    PubMed

    Hart, Christina; Vogelhuber, Martin; Wolff, Daniel; Klobuch, Sebastian; Ghibelli, Lina; Foell, Jürgen; Corbacioglu, Selim; Rehe, Klaus; Haegeman, Guy; Thomas, Simone; Herr, Wolfgang; Reichle, Albrecht

    2015-08-01

    Disruptive technologies, such as communicative reprogramming (anakoinosis) with cellular therapies in situ for treating refractory metastatic cancer allow patient care to accelerate along a totally new trajectory and highlight what may well become the next sea change in the care of patients with many types of advanced neoplasia. Cellular therapy in situ consisted of repurposed drugs, pioglitazone plus all-trans retinoic acid or dexamethasone or interferon-alpha (dual transcriptional modulation) combined with metronomic low-dose chemotherapy or low-dose 5-azacytidine, plus/minus classic targeted therapy. The novel therapeutic tools for specifically designing communication processes within tumor diseases focus on redirecting (1) rationalizations of cancer hallmarks (constitution of single cancer hallmarks), (2) modular events, (3) the 'metabolism' of evolutionary processes (the sum of therapeutically and intrinsically inducible evolutionary processes) and (4) the holistic communicative context, which determines validity and denotation of tumor promoting communication lines. Published data on cellular therapies in situ (6 histologic tumor types, 144 patients, age 0.9-83 years) in castration-resistant prostate cancer, pretreated renal clear cell carcinoma, chemorefractory acute myelocytic leukemia, multiple myeloma > second-line, chemorefractory Hodgkin lymphoma or multivisceral Langerhans cell histiocytosis, outline the possibility for treating refractory metastatic cancer with the hope that this type of reprogrammed communication will be scalable with minimal toxicity. Accessibility to anakoinosis is a tumor inherent feature, and cellular therapy in situ addresses extrinsic and intrinsic drug resistance, by redirecting convergent organized communication tools, while been supported by quite different pattern of (molecular-)genetic aberrations.

  2. Novel Method for Detection of Air Pollution using Cellular Communication Networks

    NASA Astrophysics Data System (ADS)

    David, N.; Gao, O. H.

    2016-12-01

    Air pollution can lead to a wide spectrum of severe and chronic health impacts. Conventional tools for monitoring the phenomenon do not provide a sufficient monitoring solution in a global scale since they are, for example, not representative of the larger space or due to limited deployment as a result of practical limitations, such as: acquisition, installation, and ongoing maintenance costs. Near ground temperature inversions are directly identified with air pollution events since they suppress vertical atmospheric movement and trap pollutants near the ground. Wireless telecommunication links that comprise the data transfer infrastructure in cellular communication networks operate at frequencies of tens of GHz and are affected by different atmospheric phenomena. These systems are deployed near ground level across the globe, including in developing countries such as India, countries in Africa, etc. Many cellular providers routinely store data regarding the received signal levels in the network for quality assurance needs. Temperature inversions cause atmospheric layering, and change the refractive index of the air when compared to standard conditions. As a result, the ducts that are formed can operate, in essence, as atmospheric wave guides, and cause interference (signal amplification / attenuation) in the microwaves measured by the wireless network. Thus, this network is in effect, an existing system of environmental sensors for monitoring temperature inversions and the episodes of air pollution identified with them. This work presents the novel idea, and demonstrates it, in operation, over several events of air pollution which were detected by a standard cellular communication network during routine operation. Reference: David, N. and Gao, H.O. Using cellular communication networks to detect air pollution, Environmental Science & Technology, 2016 (accepted).

  3. Microfluidic device to control interstitial flow-mediated homotypic and heterotypic cellular communication.

    PubMed

    Alonzo, Luis F; Moya, Monica L; Shirure, Venktesh S; George, Steven C

    2015-09-07

    Tissue engineering can potentially recreate in vivo cellular microenvironments in vitro for an array of applications such as biological inquiry and drug discovery. However, the majority of current in vitro systems still neglect many biological, chemical, and mechanical cues that are known to impact cellular functions such as proliferation, migration, and differentiation. To address this gap, we have developed a novel microfluidic device that precisely controls the spatial and temporal interactions between adjacent three-dimensional cellular environments. The device consists of four interconnected microtissue compartments (~0.1 mm(3)) arranged in a square. The top and bottom pairs of compartments can be sequentially loaded with discrete cellularized hydrogels creating the opportunity to investigate homotypic (left to right or x-direction) and heterotypic (top to bottom or y-direction) cell-cell communication. A controlled hydrostatic pressure difference across the tissue compartments in both x and y direction induces interstitial flow and modulates communication via soluble factors. To validate the biological significance of this novel platform, we examined the role of stromal cells in the process of vasculogenesis. Our device confirms previous observations that soluble mediators derived from normal human lung fibroblasts (NHLFs) are necessary to form a vascular network derived from endothelial colony forming cell-derived endothelial cells (ECFC-ECs). We conclude that this platform could be used to study important physiological and pathological processes that rely on homotypic and heterotypic cell-cell communication.

  4. Satellite-aided mobile communications, experiments, applications and prospects

    NASA Technical Reports Server (NTRS)

    Anderson, R. E.; Frey, R. L.; Lewis, J. R.; Milton, R. T.

    1980-01-01

    NASA's ATS-series of satellites were used in a series of communications and position fixing experiments with automotive vehicles, ships and aircraft. Applications of the communications were demonstrated and evaluated for public services including law enforcement, search and rescue, and medical emergency, and for commercial uses in the land and maritime transportation industries. The technical success of the experiments and the demonstrated potential value of the communications prompted a study that concluded an operational satellite-aided system would be a valuable augmentation of planned trunking or cellular type terrestrial mobile radio telephone systems.

  5. Plasmodesmata in integrated cell signalling: insights from development and environmental signals and stresses

    PubMed Central

    Sager, Ross; Lee, Jung-Youn

    2014-01-01

    To survive as sedentary organisms built of immobile cells, plants require an effective intercellular communication system, both locally between neighbouring cells within each tissue and systemically across distantly located organs. Such a system enables cells to coordinate their intracellular activities and produce concerted responses to internal and external stimuli. Plasmodesmata, membrane-lined intercellular channels, are essential for direct cell-to-cell communication involving exchange of diffusible factors, including signalling and information molecules. Recent advances corroborate that plasmodesmata are not passive but rather highly dynamic channels, in that their density in the cell walls and gating activities are tightly linked to developmental and physiological processes. Moreover, it is becoming clear that specific hormonal signalling pathways play crucial roles in relaying primary cellular signals to plasmodesmata. In this review, we examine a number of studies in which plasmodesmal structure, occurrence, and/or permeability responses are found to be altered upon given cellular or environmental signals, and discuss common themes illustrating how plasmodesmal regulation is integrated into specific cellular signalling pathways. PMID:25262225

  6. RF characteristics of the hoop column antenna for the land mobile satellite system mission

    NASA Astrophysics Data System (ADS)

    Foldes, P.

    1984-11-01

    A communication system using a satellite with a 118 meter diameter quad aperture antenna to provide telephone service to mobile users remotely located from the large metropolitan areas where the telephone companies are presently implementing their cellular system is described. In this system, which is compatible with the cellular system, the mobile user communicates with the satellite at UHF frequencies. The satellite connects him at S-Band, to the existing telephone network via a base station. The results of the RF definition work for the quad aperture antenna are presented. The elements of the study requirements for the LMSS are summarized, followed by a beam topology plan which satisfies the mission requirements with a practical and realiable configuration. The geometry of the UHF antenna and its radiation characteristics are defined. The various feed alternatives, and the S-band aperture are described.

  7. RF characteristics of the hoop column antenna for the land mobile satellite system mission

    NASA Technical Reports Server (NTRS)

    Foldes, P.

    1984-01-01

    A communication system using a satellite with a 118 meter diameter quad aperture antenna to provide telephone service to mobile users remotely located from the large metropolitan areas where the telephone companies are presently implementing their cellular system is described. In this system, which is compatible with the cellular system, the mobile user communicates with the satellite at UHF frequencies. The satellite connects him at S-Band, to the existing telephone network via a base station. The results of the RF definition work for the quad aperture antenna are presented. The elements of the study requirements for the LMSS are summarized, followed by a beam topology plan which satisfies the mission requirements with a practical and realiable configuration. The geometry of the UHF antenna and its radiation characteristics are defined. The various feed alternatives, and the S-band aperture are described.

  8. Analysis of Human Mobility Based on Cellular Data

    NASA Astrophysics Data System (ADS)

    Arifiansyah, F.; Saptawati, G. A. P.

    2017-01-01

    Nowadays not only adult but even teenager and children have then own mobile phones. This phenomena indicates that the mobile phone becomes an important part of everyday’s life. Based on these indication, the amount of cellular data also increased rapidly. Cellular data defined as the data that records communication among mobile phone users. Cellular data is easy to obtain because the telecommunications company had made a record of the data for the billing system of the company. Billing data keeps a log of the users cellular data usage each time. We can obtained information from the data about communication between users. Through data visualization process, an interesting pattern can be seen in the raw cellular data, so that users can obtain prior knowledge to perform data analysis. Cellular data processing can be done using data mining to find out human mobility patterns and on the existing data. In this paper, we use frequent pattern mining and finding association rules to observe the relation between attributes in cellular data and then visualize them. We used weka tools for finding the rules in stage of data mining. Generally, the utilization of cellular data can provide supporting information for the decision making process and become a data support to provide solutions and information needed by the decision makers.

  9. PDA-phone-based instant transmission of radiological images over a CDMA network by combining the PACS screen with a Bluetooth-interfaced local wireless link.

    PubMed

    Kim, Dong Keun; Yoo, Sun K; Park, Jeong Jin; Kim, Sun Ho

    2007-06-01

    Remote teleconsultation by specialists is important for timely, correct, and specialized emergency surgical and medical decision making. In this paper, we designed a new personal digital assistant (PDA)-phone-based emergency teleradiology system by combining cellular communication with Bluetooth-interfaced local wireless links. The mobility and portability resulting from the use of PDAs and wireless communication can provide a more effective means of emergency teleconsultation without requiring the user to be limited to a fixed location. Moreover, it enables synchronized radiological image sharing between the attending physician in the emergency room and the remote specialist on picture archiving and communication system terminals without distorted image acquisition. To enable rapid and fine-quality radiological image transmission over a cellular network in a secure manner, progressive compression and security mechanisms have been incorporated. The proposed system is tested over a code division Multiple Access 1x-Evolution Data-Only network to evaluate the performance and to demonstrate the feasibility of this system in a real-world setting.

  10. Architectures and protocols for an integrated satellite-terrestrial mobile system

    NASA Technical Reports Server (NTRS)

    Delre, E.; Dellipriscoli, F.; Iannucci, P.; Menolascino, R.; Settimo, F.

    1993-01-01

    This paper aims to depict some basic concepts related to the definition of an integrated system for mobile communications, consisting of a satellite network and a terrestrial cellular network. In particular three aspects are discussed: (1) architecture definition for the satellite network; (2) assignment strategy of the satellite channels; and (3) definition of 'internetworking procedures' between cellular and satellite network, according to the selected architecture and the satellite channel assignment strategy.

  11. Personal communications services: Improving theater deployable communications for the 21st century

    NASA Astrophysics Data System (ADS)

    Cournoyer, Ronald C., Jr.

    1994-06-01

    Personal Communications Services (PCS) may be the key ingredient for vastly improved military communications capabilities at the turn of the century. The Federal Communications Commission (FCC) defines PCS as a family of mobile or portable radio communications services which could provide services to individuals and businesses and be integrated with a variety of competing networks ... the primary focus of PCS will be to meet communications requirements of people on the move. Today's generation of Theater Deployable Communications, which provides joint tactical communications to deployed forces, is the Tri-Service Tactical Communications (TRI-TAC) system. A description of TRITAC's family of equipment, network topology, typical employment, and critical limitations is presented in this thesis. Five commercial Mobile Satellite Services (MSS) are described as viable candidates for augmenting existing communications systems. Cellular design principles such as frequency reuse, cell splitting, channel access methods, and propagation factors are also addressed. Finally, a framework for comparison of the candidate MSS systems is proposed as a baseline for further studies into the most beneficial implementation of PCS into theater deployable communications systems for the future.

  12. Systems Biology Analysis of Heterocellular Signaling.

    PubMed

    Tape, Christopher J

    2016-08-01

    Tissues comprise multiple heterotypic cell types (e.g., epithelial, mesenchymal, and immune cells). Communication between heterotypic cell types is essential for biological cohesion and is frequently dysregulated in disease. Despite the importance of heterocellular communication, most systems biology techniques do not report cell-specific signaling data from mixtures of cells. As a result, our existing perspective of cellular behavior under-represents the influence of heterocellular signaling. Recent technical advances now permit the resolution of systems-level cell-specific signaling data. This review discusses how new physical, spatial, and isotopic resolving methods are facilitating unique systems biology studies of heterocellular communication. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. A Game Theoretic Optimization Method for Energy Efficient Global Connectivity in Hybrid Wireless Sensor Networks

    PubMed Central

    Lee, JongHyup; Pak, Dohyun

    2016-01-01

    For practical deployment of wireless sensor networks (WSN), WSNs construct clusters, where a sensor node communicates with other nodes in its cluster, and a cluster head support connectivity between the sensor nodes and a sink node. In hybrid WSNs, cluster heads have cellular network interfaces for global connectivity. However, when WSNs are active and the load of cellular networks is high, the optimal assignment of cluster heads to base stations becomes critical. Therefore, in this paper, we propose a game theoretic model to find the optimal assignment of base stations for hybrid WSNs. Since the communication and energy cost is different according to cellular systems, we devise two game models for TDMA/FDMA and CDMA systems employing power prices to adapt to the varying efficiency of recent wireless technologies. The proposed model is defined on the assumptions of the ideal sensing field, but our evaluation shows that the proposed model is more adaptive and energy efficient than local selections. PMID:27589743

  14. Reaching Forward in the War against the Islamic State

    DTIC Science & Technology

    2016-12-07

    every week with U.S.- and Coalition-advised ISOF troops taking the lead in combat operations using cellular communications systems that link them...tions—Offline Maps, Google Earth , and Viber, to name a few—which allowed them to bring tablets and phones on their operations to help communicate ...provided an initial Remote Advise and Assist capability that enabled the special forces advisors to track, communicate , and share limited data with

  15. 47 CFR 22.959 - Rules governing processing of applications for initial systems.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... initial systems. 22.959 Section 22.959 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.959 Rules governing processing of applications for initial systems. Pending applications for authority to operate the first...

  16. Riding the Waves: How Our Cells Send Signals | Center for Cancer Research

    Cancer.gov

    The ability of cells to perceive and respond to their environment is critical in order to maintain basic cellular functions such as development, tissue repair, and response to stress. This process happens through a complex system of communication, called cell signaling, which governs basic cellular activities and coordinates cell actions. Errors in cell signaling have been

  17. Economic-Analysis Program for a Communication System

    NASA Technical Reports Server (NTRS)

    Chamberlain, R. G.

    1986-01-01

    Prices and profits of alternative designs compared. Objective of Land Mobile Satellite Service Finance Report (LMSS) program is to provide means for comparing alternative designs of LMSS systems. Program is Multiplan worksheet program. Labels used in worksheet chosen for satellite-based cellular communication service, but analysis not restricted to such cases. LMSS written for interactive execution with Multiplan (version 1.2) and implemented on IBM PC series computer operating under DOS (version 2.11).

  18. Application of AirCell Cellular AMPS Network and Iridium Satellite System Dual Mode Service to Air Traffic Management

    NASA Technical Reports Server (NTRS)

    Shamma, Mohammed A.

    2004-01-01

    The AirCell/Iridium dual mode service is evaluated for potential applications to Air Traffic Management (ATM) communication needs. The AirCell system which is largely based on the Advanced Mobile Phone System (AMPS) technology, and the Iridium FDMA/TDMA system largely based on the Global System for Mobile Communications(GSM) technology, can both provide communication relief for existing or future aeronautical communication links. Both have a potential to serve as experimental platforms for future technologies via a cost effective approach. The two systems are well established in the entire CONUS and globally hence making it feasible to utilize in all regions, for all altitudes, and all classes of aircraft. Both systems have been certified for air usage. The paper summarizes the specifications of the AirCell/Iridium system, as well as the ATM current and future links, and application specifications. the paper highlights the scenarios, applications, and conditions under which the AirCell/Iridium technology can be suited for ATM Communication.

  19. Proceedings of the Third International Mobile Satellite Conference (IMSC 1993)

    NASA Technical Reports Server (NTRS)

    Kwan, Robert (Compiler); Rigley, Jack (Compiler); Cassingham, Randy (Editor)

    1993-01-01

    Satellite-based mobile communications systems provide voice and data communications to users over a vast geographic area. The users may communicate via mobile or hand-held terminals, which may also provide access to terrestrial cellular communications services. While the first and second International Mobile Satellite Conferences (IMSC) mostly concentrated on technical advances, this Third IMSC also focuses on the increasing worldwide commercial activities in Mobile Satellite Services. Because of the large service areas provided by such systems, it is important to consider political and regulatory issues in addition to technical and user requirements issues. Topics covered include: the direct broadcast of audio programming from satellites; spacecraft technology; regulatory and policy considerations; advanced system concepts and analysis; propagation; and user requirements and applications.

  20. A new approach to telemetry data processing. Ph.D. Thesis - Maryland Univ.

    NASA Technical Reports Server (NTRS)

    Broglio, C. J.

    1973-01-01

    An approach for a preprocessing system for telemetry data processing was developed. The philosophy of the approach is the development of a preprocessing system to interface with the main processor and relieve it of the burden of stripping information from a telemetry data stream. To accomplish this task, a telemetry preprocessing language was developed. Also, a hardware device for implementing the operation of this language was designed using a cellular logic module concept. In the development of the hardware device and the cellular logic module, a distributed form of control was implemented. This is accomplished by a technique of one-to-one intermodule communications and a set of privileged communication operations. By transferring this control state from module to module, the control function is dispersed through the system. A compiler for translating the preprocessing language statements into an operations table for the hardware device was also developed. Finally, to complete the system design and verify it, a simulator for the collular logic module was written using the APL/360 system.

  1. An Interference Mitigation Scheme of Device-to-Device Communications for Sensor Networks Underlying LTE-A

    PubMed Central

    Kim, Jeehyeong; Karim, Nzabanita Abdoul; Cho, Sunghyun

    2017-01-01

    Device-to-Device (D2D) communication technology has become a key factor in wireless sensor networks to form autonomous communication links among sensor nodes. Many research results for D2D have been presented to resolve different technical issues of D2D. Nevertheless, the previous works have not resolved the shortage of data rate and limited coverage of wireless sensor networks. Due to bandwidth shortages and limited communication coverage, 3rd Generation Partnership Project (3GPP) has introduced a new Device-to-Device (D2D) communication technique underlying cellular networks, which can improve spectral efficiencies by enabling the direct communication of devices in proximity without passing through enhanced-NodeB (eNB). However, to enable D2D communication in a cellular network presents a challenge with regard to radio resource management since D2D links reuse the uplink radio resources of cellular users and it can cause interference to the receiving channels of D2D user equipment (DUE). In this paper, a hybrid mechanism is proposed that uses Fractional Frequency Reuse (FFR) and Almost Blank Sub-frame (ABS) schemes to handle inter-cell interference caused by cellular user equipments (CUEs) to D2D receivers (DUE-Rxs), reusing the same resources at the cell edge area. In our case, DUE-Rxs are considered as victim nodes and CUEs as aggressor nodes, since our primary target is to minimize inter-cell interference in order to increase the signal to interference and noise ratio (SINR) of the target DUE-Rx at the cell edge area. The numerical results show that the interference level of the target D2D receiver (DUE-Rx) decreases significantly compared to the conventional FFR at the cell edge. In addition, the system throughput of the proposed scheme can be increased up to 60% compared to the conventional FFR. PMID:28489064

  2. An Interference Mitigation Scheme of Device-to-Device Communications for Sensor Networks Underlying LTE-A.

    PubMed

    Kim, Jeehyeong; Karim, Nzabanita Abdoul; Cho, Sunghyun

    2017-05-10

    Device-to-Device (D2D) communication technology has become a key factor in wireless sensor networks to form autonomous communication links among sensor nodes. Many research results for D2D have been presented to resolve different technical issues of D2D. Nevertheless, the previous works have not resolved the shortage of data rate and limited coverage of wireless sensor networks. Due to bandwidth shortages and limited communication coverage, 3rd Generation Partnership Project (3GPP) has introduced a new Device-to-Device (D2D) communication technique underlying cellular networks, which can improve spectral efficiencies by enabling the direct communication of devices in proximity without passing through enhanced-NodeB (eNB). However, to enable D2D communication in a cellular network presents a challenge with regard to radio resource management since D2D links reuse the uplink radio resources of cellular users and it can cause interference to the receiving channels of D2D user equipment (DUE). In this paper, a hybrid mechanism is proposed that uses Fractional Frequency Reuse (FFR) and Almost Blank Sub-frame (ABS) schemes to handle inter-cell interference caused by cellular user equipments (CUEs) to D2D receivers (DUE-Rxs), reusing the same resources at the cell edge area. In our case, DUE-Rxs are considered as victim nodes and CUEs as aggressor nodes, since our primary target is to minimize inter-cell interference in order to increase the signal to interference and noise ratio (SINR) of the target DUE-Rx at the cell edge area. The numerical results show that the interference level of the target D2D receiver (DUE-Rx) decreases significantly compared to the conventional FFR at the cell edge. In addition, the system throughput of the proposed scheme can be increased up to 60% compared to the conventional FFR.

  3. Cellular and circuit properties supporting different sensory coding strategies in electric fish and other systems.

    PubMed

    Marsat, Gary; Longtin, André; Maler, Leonard

    2012-08-01

    Neural codes often seem tailored to the type of information they must carry. Here we contrast the encoding strategies for two different communication signals in electric fish and describe the underlying cellular and network properties that implement them. We compare an aggressive signal that needs to be quickly detected, to a courtship signal whose quality needs to be evaluated. The aggressive signal is encoded by synchronized bursts and a predictive feedback input is crucial in separating background noise from the communication signal. The courtship signal is accurately encoded through a heterogenous population response allowing the discrimination of signal differences. Most importantly we show that the same strategies are used in other systems arguing that they evolved similar solutions because they faced similar tasks. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. Network flexibility of the IRIDIUM (R) Global Mobile Satellite System

    NASA Technical Reports Server (NTRS)

    Hutcheson, Jonathan; Laurin, Mala

    1995-01-01

    The IRIDIUM system is a global personal communications system supported by a constellation of 66 low earth orbit (LEO) satellites and a collection of earth-based 'gateway' switching installations. Like traditional wireless cellular systems, coverage is achieved by a grid of cells in which bandwidth is reused for spectral efficiency. Unlike any cellular system ever built, the moving cells can be shared by multiple switching facilities. Noteworthy features of the IRIDIUM system include inter-satellite links, a GSM-based telephony architecture, and a geographically controlled system access process. These features, working in concert, permit flexible and reliable administration of the worldwide service area by gateway operators. This paper will explore this unique concept.

  5. 47 CFR 22.901 - Cellular service requirements and limitations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    .... 22.901 Section 22.901 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.901 Cellular service requirements and... radiotelephone, dispatch, one way or two way paging, and personal communications services (as defined in part 24...

  6. 47 CFR 22.901 - Cellular service requirements and limitations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    .... 22.901 Section 22.901 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.901 Cellular service requirements and... radiotelephone, dispatch, one way or two way paging, and personal communications services (as defined in part 24...

  7. 47 CFR 22.911 - Cellular geographic service area.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Section 22.911 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.911 Cellular geographic service area. The... Communications Act of 1934, as amended, is applicable. [59 FR 59507, Nov. 17, 1994, as amended at 59 FR 59954...

  8. 47 CFR 22.911 - Cellular geographic service area.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Section 22.911 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.911 Cellular geographic service area. The... Communications Act of 1934, as amended, is applicable. [59 FR 59507, Nov. 17, 1994, as amended at 59 FR 59954...

  9. Addendum to the Proceedings of the Third International Mobile Satellite Conference (IMSC 1993)

    NASA Technical Reports Server (NTRS)

    Kwan, Robert (Compiler); Rigley, Jack (Compiler); Cassingham, Randy (Editor)

    1993-01-01

    Satellite-based mobile communications systems provide voice and data communications to users over a vast geographic area. The users may communicate via mobile or hand-held terminals, which may also provide access to terrestrial cellular communications services. This Third IMSC focuses on the increasing worldwide commercial activities in Mobile Satellite Services, along with technical advances in the field. Because of the large service areas provided by such systems, it is important to consider political and regulatory issues in addition to technical and user requirements issues. The official Proceedings presented in 11 sessions include: direct broadcast of audio programming from satellites; spacecraft technology; regulatory and policy considerations; hybrid networks for personal and mobile applications; advanced system concepts and analysis; propagation; and mobile terminal technology; and mobile antenna technology.

  10. Influence of digital and analogue cellular telephones on implanted pacemakers.

    PubMed

    Altamura, G; Toscano, S; Gentilucci, G; Ammirati, F; Castro, A; Pandozi, C; Santini, M

    1997-10-01

    The aim of this study was to find out whether digital and analogue cellular 'phones affect patients with pacemakers. The study comprised continuous ECG monitoring of 200 pacemaker patients. During the monitoring certain conditions caused by interference created by the telephone were looked for: temporary or prolonged pacemaker inhibition; a shift to asynchronous mode caused by electromagnetic interference; an increase in ventricular pacing in dual chamber pacemakers, up to the programmed upper rate. The Global System for Mobile Communications system interfered with pacing 97 times in 43 patients (21.5%). During tests on Total Access of Communication System telephones, there were 60 cases of pacing interference in 35 patients (17.5%). There were 131 interference episodes during ringing vs 26 during the on/off phase; (P < 0.0001); 106 at maximum sensitivity level vs 51 at the 'base' value; P < 0.0001). Prolonged pacing inhibition (> 4 s) was seen at the pacemaker 'base' sensing value in six patients using the Global system but in only one patient using Total Access. Cellular 'phones may be dangerous for pacemaker patients. However, they can be used safely if patients do not carry the 'phone close to the pacemaker, which is the only place where high risk interference has been observed.

  11. The mammary cellular hierarchy and breast cancer.

    PubMed

    Oakes, Samantha R; Gallego-Ortega, David; Ormandy, Christopher J

    2014-11-01

    Advances in the study of hematopoietic cell maturation have paved the way to a deeper understanding the stem and progenitor cellular hierarchy in the mammary gland. The mammary epithelium, unlike the hematopoietic cellular hierarchy, sits in a complex niche where communication between epithelial cells and signals from the systemic hormonal milieu, as well as from extra-cellular matrix, influence cell fate decisions and contribute to tissue homeostasis. We review the discovery, definition and regulation of the mammary cellular hierarchy and we describe the development of the concepts that have guided our investigations. We outline recent advances in in vivo lineage tracing that is now challenging many of our assumptions regarding the behavior of mammary stem cells, and we show how understanding these cellular lineages has altered our view of breast cancer.

  12. Concepts for fast acquisition in optical communications systems

    NASA Astrophysics Data System (ADS)

    Wilkerson, Brandon L.; Giggenbach, Dirk; Epple, Bernhard

    2006-09-01

    As free-space laser communications systems proliferate due to improved technology and transmission techniques, optical communication networks comprised of ground stations, aircraft, high altitude platforms, and satellites become an attainable goal. An important consideration for optical networks is the ability of optical communication terminals (OCT) to quickly locate one another and align their laser beams to initiate the acquisition sequence. This paper investigates promising low-cost technologies and novel approaches that will facilitate the targeting and acquisition tasks between counter terminals. Specifically, two critical technology areas are investigated: position determination (which includes location and attitude determination) and inter-terminal communications. A feasibility study identified multiple-antenna global navigation satellite system (GNSS) systems and GNSS-aided inertial systems as possible position determination solutions. Personal satellite communication systems (e.g. Iridium or Inmarsat), third generation cellular technology (IMT-2000/UMTS), and a relatively new air traffic surveillance technology called Autonomous Dependent Surveillance-Broadcast (ADS-B) were identified as possible inter-terminal communication solutions. A GNSS-aided inertial system and an ADS-B system were integrated into an OCT to demonstrate their utility in a typical optical communication scenario. Testing showed that these technologies have high potential in future OCTs, although improvements can be made to both to increase tracking accuracy.

  13. System on a chip with MPEG-4 capability

    NASA Astrophysics Data System (ADS)

    Yassa, Fathy; Schonfeld, Dan

    2002-12-01

    Current products supporting video communication applications rely on existing computer architectures. RISC processors have been used successfully in numerous applications over several decades. DSP processors have become ubiquitous in signal processing and communication applications. Real-time applications such as speech processing in cellular telephony rely extensively on the computational power of these processors. Video processors designed to implement the computationally intensive codec operations have also been used to address the high demands of video communication applications (e.g., cable set-top boxes and DVDs). This paper presents an overview of a system-on-chip (SOC) architecture used for real-time video in wireless communication applications. The SOC specifications answer to the system requirements imposed by the application environment. A CAM-based video processor is used to accelerate data intensive video compression tasks such as motion estimations and filtering. Other components are dedicated to system level data processing and audio processing. A rich set of I/Os allows the SOC to communicate with other system components such as baseband and memory subsystems.

  14. Improving Communications Systems

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The Space Shuttle has many communications systems which are used throughout a typical mission. Given that the radio spectrum has become increasingly congested, the ability to hear extremely weak signals requires greater receiver sensitivity. Dryden Flight Research Center approached Angle Linear, a manufacturer of linear radio frequency products and peripherals for communications, to solve the problem. The solution was a receiving preamplifier specially crafted for NASA. Communications with the Space Shuttle are now more reliable,with Dryden being able to also support local missions without purchasing additional equipment. The work has carried over into the Mir Space Station communication support effort and is under evaluation by other NASA centers. The company's preamplifier line was greatly expanded to cover a broader range of frequencies, providing the same sensational improvement to other areas of communication including business, government, trucking, land mobile, cellular and broadcast.

  15. High Altitude Platforms for Disaster Recovery: Capabilities, Strategies, and Techniques for Providing Emergency Telecommunications

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

    Juan D. Deaton

    2008-05-01

    Natural disasters and terrorist acts have significant potential to disrupt emergency communication systems. These emergency communication networks include first-responder, cellular, landline, and emergency answering services such as 911, 112, or 999. Without these essential emergency communications capabilities, search, rescue, and recovery operations during a catastrophic event will be severely debilitated. High altitude platforms could be fitted with telecommunications equipment and used to support these critical communications missions once the catastrophic event occurs. With the ability to be continuously on station, HAPs provide excellent options for providing emergency coverage over high-risk areas before catastrophic incidents occur. HAPs could also provide enhancedmore » 911 capabilities using either GPS or reference stations. This paper proposes potential emergency communications architecture and presents a method for estimating emergency communications systems traffic patterns for a catastrophic event.« less

  16. The Scientist as Illustrator.

    PubMed

    Iwasa, Janet H

    2016-04-01

    Proficiency in art and illustration was once considered an essential skill for biologists, because text alone often could not suffice to describe observations of biological systems. With modern imaging technology, it is no longer necessary to illustrate what we can see by eye. However, in molecular and cellular biology, our understanding of biological processes is dependent on our ability to synthesize diverse data to generate a hypothesis. Creating visual models of these hypotheses is important for generating new ideas and for communicating to our peers and to the public. Here, I discuss the benefits of creating visual models in molecular and cellular biology and consider steps to enable researchers to become more effective visual communicators. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Regulation of Cellular Communication by Signaling Microdomains in the Blood Vessel Wall

    PubMed Central

    Billaud, Marie; Lohman, Alexander W.; Johnstone, Scott R.; Biwer, Lauren A.; Mutchler, Stephanie; Isakson, Brant E.

    2014-01-01

    It has become increasingly clear that the accumulation of proteins in specific regions of the plasma membrane can facilitate cellular communication. These regions, termed signaling microdomains, are found throughout the blood vessel wall where cellular communication, both within and between cell types, must be tightly regulated to maintain proper vascular function. We will define a cellular signaling microdomain and apply this definition to the plethora of means by which cellular communication has been hypothesized to occur in the blood vessel wall. To that end, we make a case for three broad areas of cellular communication where signaling microdomains could play an important role: 1) paracrine release of free radicals and gaseous molecules such as nitric oxide and reactive oxygen species; 2) role of ion channels including gap junctions and potassium channels, especially those associated with the endothelium-derived hyperpolarization mediated signaling, and lastly, 3) mechanism of exocytosis that has considerable oversight by signaling microdomains, especially those associated with the release of von Willebrand factor. When summed, we believe that it is clear that the organization and regulation of signaling microdomains is an essential component to vessel wall function. PMID:24671377

  18. Regulation of cellular communication by signaling microdomains in the blood vessel wall.

    PubMed

    Billaud, Marie; Lohman, Alexander W; Johnstone, Scott R; Biwer, Lauren A; Mutchler, Stephanie; Isakson, Brant E

    2014-01-01

    It has become increasingly clear that the accumulation of proteins in specific regions of the plasma membrane can facilitate cellular communication. These regions, termed signaling microdomains, are found throughout the blood vessel wall where cellular communication, both within and between cell types, must be tightly regulated to maintain proper vascular function. We will define a cellular signaling microdomain and apply this definition to the plethora of means by which cellular communication has been hypothesized to occur in the blood vessel wall. To that end, we make a case for three broad areas of cellular communication where signaling microdomains could play an important role: 1) paracrine release of free radicals and gaseous molecules such as nitric oxide and reactive oxygen species; 2) role of ion channels including gap junctions and potassium channels, especially those associated with the endothelium-derived hyperpolarization mediated signaling, and lastly, 3) mechanism of exocytosis that has considerable oversight by signaling microdomains, especially those associated with the release of von Willebrand factor. When summed, we believe that it is clear that the organization and regulation of signaling microdomains is an essential component to vessel wall function.

  19. [Homeostasis and Disorder of Musculoskeletal System.Cellular dynamics in musculoskeletal system visualized by intravital imaging techniques.

    PubMed

    Kikuta, Junichi; Ishii, Masaru

    Bone is continually remodeled by bone-resorbing osteoclasts and bone-forming osteoblasts. Although it has long been believed that bone homeostasis is tightly regulated by communication between osteoclasts and osteoblasts, the fundamental process and dynamics have remained elusive. We originally established an advanced imaging system to visualize living bone tissues using intravital two-photon microscopy. By means of this system, we revealed the in vivo behavior of bone-resorbing osteoclasts and bone-forming osteoblasts in bone tissues. This approach facilitates investigation of cellular dynamics in the pathogenesis of musculoskeletal disorders, and would thus be useful for evaluating the efficacy of novel therapeutic agents.

  20. Cardiac system bioenergetics: metabolic basis of the Frank-Starling law

    PubMed Central

    Saks, Valdur; Dzeja, Petras; Schlattner, Uwe; Vendelin, Marko; Terzic, Andre; Wallimann, Theo

    2006-01-01

    The fundamental principle of cardiac behaviour is described by the Frank-Starling law relating force of contraction during systole with end-diastolic volume. While both work and respiration rates increase linearly with imposed load, the basis of mechano-energetic coupling in heart muscle has remained a long-standing enigma. Here, we highlight advances made in understanding of complex cellular and molecular mechanisms that orchestrate coupling of mitochondrial oxidative phosphorylation with ATP utilization for muscle contraction. Cardiac system bioenergetics critically depends on an interrelated metabolic infrastructure regulating mitochondrial respiration and energy fluxes throughout cellular compartments. The data reviewed indicate the significance of two interrelated systems regulating mitochondrial respiration and energy fluxes in cells: (1) the creatine kinase, adenylate kinase and glycolytic pathways that communicate flux changes generated by cellular ATPases within structurally organized enzymatic modules and networks; and (2) a secondary system based on mitochondrial participation in cellular calcium cycle, which adjusts substrate oxidation and energy-transducing processes to meet increasing cellular energy demands. By conveying energetic signals to metabolic sensors, coupled phosphotransfer reactions provide a high-fidelity regulation of the excitation–contraction cycle. Such integration of energetics with calcium signalling systems provides the basis for ‘metabolic pacing’, synchronizing the cellular electrical and mechanical activities with energy supply processes. PMID:16410283

  1. Microwave components for cellular portable radiotelephone

    NASA Astrophysics Data System (ADS)

    Muraguchi, Masahiro; Aikawa, Masayoshi

    1995-09-01

    Mobile and personal communication systems are expected to represent a huge market for microwave components in the coming years. A number of components in silicon bipolar, silicon Bi-CMOS, GaAs MESFET, HBT and HEMT are now becoming available for system application. There are tradeoffs among the competing technologies with regard to performance, cost, reliability and time-to-market. This paper describes process selection and requirements of cost and r.f. performances to microwave semiconductor components for digital cellular and cordless telephones. Furthermore, new circuit techniques which were developed by NTT are presented.

  2. Design approach for solar cell and battery of a persistent solar powered GPS tracker

    NASA Astrophysics Data System (ADS)

    Sahraei, Nasim; Watson, Sterling M.; Pennes, Anthony; Marius Peters, Ian; Buonassisi, Tonio

    2017-08-01

    Sensors with wireless communication can be powered by photovoltaic (PV) devices. However, using solar power requires thoughtful design of the power system, as well as a careful management of the power consumption, especially for devices with cellular communication (because of their higher power consumption). A design approach can minimize system size, weight, and/or cost, while maximizing device performance (data transmission rate and persistence). In this contribution, we describe our design approach for a small form-factor, solar-powered GPS tracker with cellular communication. We evaluate the power consumption of the device in different stages of operation. Combining measured power consumption and the calculated energy-yield of a solar cell, we estimate the battery capacity and solar cell area required for 5 years of continuous operation. We evaluate trade-offs between PV and battery size by simulating the battery state of charge. The data show a trade-off between battery capacity and solar-cell area for given target data transmission rate and persistence. We use this analysis to determine the combination of solar panel area and battery capacity for a given application and the data transmission rate that results in minimum cost or total weight of the system.

  3. A design of wireless sensor networks for a power quality monitoring system.

    PubMed

    Lim, Yujin; Kim, Hak-Man; Kang, Sanggil

    2010-01-01

    Power grids deal with the business of generation, transmission, and distribution of electric power. Recently, interest in power quality in electrical distribution systems has increased rapidly. In Korea, the communication network to deliver voltage, current, and temperature measurements gathered from pole transformers to remote monitoring centers employs cellular mobile technology. Due to high cost of the cellular mobile technology, power quality monitoring measurements are limited and data gathering intervals are large. This causes difficulties in providing the power quality monitoring service. To alleviate the problems, in this paper we present a communication infrastructure to provide low cost, reliable data delivery. The communication infrastructure consists of wired connections between substations and monitoring centers, and wireless connections between pole transformers and substations. For the wireless connection, we employ a wireless sensor network and design its corresponding data forwarding protocol to improve the quality of data delivery. For the design, we adopt a tree-based data forwarding protocol in order to customize the distribution pattern of the power quality information. We verify the performance of the proposed data forwarding protocol quantitatively using the NS-2 network simulator.

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

    Michael Schmitt; Juan Deaton; Curt Papke

    In the event of large-scale natural or manmade catastrophic events, access to reliable and enduring commercial communication systems is critical. Hurricane Katrina provided a recent example of the need to ensure communications during a national emergency. To ensure that communication demands are met during these critical times, Idaho National Laboratory (INL) under the guidance of United States Strategic Command has studied infrastructure issues, concerns, and vulnerabilities associated with an airborne wireless communications capability. Such a capability could provide emergency wireless communications until public/commercial nodes can be systematically restored. This report focuses on the airborne cellular restoration concept; analyzing basic infrastructuremore » requirements; identifying related infrastructure issues, concerns, and vulnerabilities and offers recommended solutions.« less

  5. Miniature Transportable Communications Central (MTCC): answering law enforcement needs for worldwide access to command, control, communications, and intelligence (C3I)

    NASA Astrophysics Data System (ADS)

    Maxey, W. John

    1997-02-01

    The Mini-Transportable Communications Central (MTCC), developed by Rome Laboratories C3 Directorate, provides the U.S. Coast Guard (USCG) with a transportable, fast reaction communications terminal. The MTCC is capable of operating as a self-contained miniature command center supporting efforts such as the President's War on Drugs, or the rescue services necessary in the wake of man-made or natural disasters. The MTCC is capable of communicating with field elements including ships, small water-craft, aircraft, other elements of the USCG law enforcement agencies (LEAs), the FAA, and a wide range of U.S. and foreign armed forces. The MTCC terminal is contained in a trailer-mounted shelter suitable for towing by a 3/4 ton truck or for transport by C-130 aircraft. The MTCC provides simultaneous one-way and two-way communications in the HF, VHF, and UHF frequency bands, as well as the INMARSAT international satellite band. The MTCC also offers communications through subscriber and trunk telephone connectivity via ISDN compatible PABX. The MTCC's three channel operations personnel cellular telephone system provides self-contained cellular telephone operations in the vicinity of the deployed shelter. In the USCG application, an operator console inside the air-conditioned shelter serves as the source and destination for voice, data, and fax traffic, by means of secure fax telephone, operator headsets, and a powerful computer workstation that provides word processing, e-mail, and data communications capabilities. The communications operator may reconfigure the system for a specific mission by means of patchfields that enable the selection of radios, encrypted or clear-text operations, audio termination, and antennas.

  6. Smart call box field operational test evaluation : subtest reports

    DOT National Transportation Integrated Search

    1997-05-01

    Smart call boxes are an enhanced version of devices used as emergency call boxes in California. The overall system consists of a microprocessor, a cellular communications transceiver, solar power sources, data collection devices, maintenance computer...

  7. Smart call box field operational test evaluation : summary report

    DOT National Transportation Integrated Search

    1997-05-01

    Smart call boxes are an enhanced version of devices used as emergency call boxes in California. The overall system consists of a microprocessor, a cellular communications transceiver, solar power sources, data collection devices, maintenance computer...

  8. A Chemical Biology Approach to Interrogate Quorum Sensing Regulated Behaviors at the Molecular and Cellular Level

    PubMed Central

    Lowery, Colin A.; Matamouros, Susana; Niessen, Sherry; Zhu, Jie; Scolnick, Jonathan A.; Mee, Jenny M.; Cravatt, Benjamin F.; Miller, Samuel I.; Kaufmann, Gunnar F.; Janda, Kim D.

    2013-01-01

    SUMMARY Small molecule probes have been employed extensively to explore biological systems and elucidate cellular signaling pathways. In this study, we utilize an inhibitor of bacterial communication to monitor changes in the proteome of Salmonella enterica serovar Typhimurium with the aim of discovering new processes regulated by AI-2-based quorum sensing (QS), a mechanism of bacterial intracellular communication that allows for the coordination of gene expression in a cell density-dependent manner. In S. typhimurium, this system regulates the uptake and catabolism of intracellular signals and has been implicated in pathogenesis, including the invasion of host epithelial cells. We demonstrate that our QS antagonist is capable of selectively inhibiting the expression of known QS-regulated proteins in S. typhimurium, thus attesting that QS inhibitors may be used to confirm proposed and elucidate previously unidentified QS pathways without relying on genetic manipulation. PMID:23890008

  9. [Two-nuclear neurons: sincitial fusion or amitotic division].

    PubMed

    Sotnikov, O S; Frumkina, L E; Lactionova, A A; Paramonova, N M; Novakovskaia, S A

    2011-01-01

    In the review the history of research two-nuclear neurons is stated and two hypotheses about mechanisms of their formation are analysed: by sincitial fusion or amytotic divisions. The facts of discrepancy of the former orthodox cellular theory categorically denying possibility sincitial of communications in nervous system and of sincitial fusion neurons are mentioned. As an example results of ultrastructural researches of occurrence sincitium in a cortex of the big brain of rats, in autonomic ganglions, in hypocampus and a cerebellum of adult animals are presented. The video data of the sincitial fusion of live neurons and the mechanism of formation multinuclear neurons in tissue culture are analyzed. Existing data about amytotic a way of formation two-nuclear neurons are critically considered. The conclusion becomes, that the mechanism of formation two-nuclear neurons is cellular fusion. Simultaneously the review confirms our representations about existence in nervous system sincitial interneural communications.

  10. A chemical biology approach to interrogate quorum-sensing regulated behaviors at the molecular and cellular level.

    PubMed

    Lowery, Colin A; Matamouros, Susana; Niessen, Sherry; Zhu, Jie; Scolnick, Jonathan; Lively, Jenny M; Cravatt, Benjamin F; Miller, Samuel I; Kaufmann, Gunnar F; Janda, Kim D

    2013-07-25

    Small molecule probes have been used extensively to explore biologic systems and elucidate cellular signaling pathways. In this study, we use an inhibitor of bacterial communication to monitor changes in the proteome of Salmonella enterica serovar Typhimurium with the aim of discovering unrecognized processes regulated by AI-2-based quorum-sensing (QS), a mechanism of bacterial intercellular communication that allows for the coordination of gene expression in a cell density-dependent manner. In S. typhimurium, this system regulates the uptake and catabolism of intercellular signals and has been implicated in pathogenesis, including the invasion of host epithelial cells. We demonstrate that our QS antagonist is capable of selectively inhibiting the expression of known QS-regulated proteins in S. typhimurium, thus attesting that QS inhibitors may be used to confirm proposed and elucidate previously unidentified QS pathways without relying on genetic manipulation. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Teen Perceptions of Cellular Phones as a Communication Tool

    ERIC Educational Resources Information Center

    Jonas, Denise D.

    2011-01-01

    The excitement and interest in innovative technologies has spanned centuries. However, the invention of the cellular phone has surpassed previous technology interests, and changed the way we communicate today. Teens make up the fastest growing market of current cellular phone users. Consequently, the purpose of this study was to determine teen…

  12. Perceptual telerobotics

    NASA Technical Reports Server (NTRS)

    Ligomenides, Panos A.

    1989-01-01

    A sensory world modeling system, congruent with a human expert's perception, is proposed. The Experiential Knowledge Base (EKB) system can provide a highly intelligible communication interface for telemonitoring and telecontrol of a real time robotic system operating in space. Paradigmatic acquisition of empirical perceptual knowledge, and real time experiential pattern recognition and knowledge integration are reviewed. The cellular architecture and operation of the EKB system are also examined.

  13. A most spectrum-efficient duplexing system: CDD

    NASA Astrophysics Data System (ADS)

    Lee, William C. Y.

    2001-10-01

    The game to play in wireless communications when it comes to increasing spectrum efficiency is to eliminate interference. Currently, all cellular systems use FDD (Frequency Division Duplexing) in an attempt to eliminate the interference from the adjacent cells. Through the use of many technologies only one type of interference remains and that is the adjacent base-tohome mobile interference. TDD (Time Division Duplexing) has not been used for mobile cellular systems, not only because of the adjacent base-to-home mobile interference, but also because of the additional adjacent base-to-home base interference, and adjacent mobile-to-home mobile interference. Therefore, TDD can only be used for small, confined area systems. CDD (Code Division Duplexing) can eliminate all three kinds of interference; the adjacent base-to-home mobile, the adjacent baseto-home base, and the adjacent mobile- to- home in cellular systems. Eliminating each of these interferences makes CDD the most spectrum efficient duplexing system. This talk will elaborate on a set of smart codes, which will make an efficient CDD system a reality.

  14. ARJIS satellite demonstration project

    NASA Astrophysics Data System (ADS)

    Severance, Steve; Williams, Carl

    2005-06-01

    In 2003, the California Space Authority (CSA) was provided funding by the U. S. Congress through the Defense Appropriations Act to develop a project that would demonstrate the U.S. space enterprise capability that would contribute to the effectiveness of those engaged in Homeland Security. The project was given broad latitude in selecting the area of Homeland Security to be addressed and the nature of the space technology to be applied. CSA became aware of a nascent law enforcement data-sharing project in the San Diego region known as the Automated Regional Justice Information System (ARJIS). First developed by the police departments in San Diego, ARJIS is an innovative system that shares criminal justice information among 50 federal, state, and local agencies. ARJIS was completing a pilot project that enabled officers to receive information on handheld computers, which was transmitted wirelessly through cellular networks. The accessed information came from several databases that collectively contained the entire region's crime and arrest reports, traffic citations, and incidents, as well as state and county wants and warrants. The fundamental limitations that plague all cellular-based devices caught CSA's attention and resulted in a cooperative effort to harden the communications link between the patrol officer and critical data. The principal goal of the SATCOM development task was to create a proof-of-concept application that would use SATCOM links to augment the current ARJIS handheld wireless (cellular) capability. The successful technical demonstration and the positive support for satellite communications from the law enforcement community showed that this project filled a need-both for improved information sharing and for highly reliable communications systems.

  15. LEOPACK The integrated services communications system based on LEO satellites

    NASA Astrophysics Data System (ADS)

    Negoda, A.; Bunin, S.; Bushuev, E.; Dranovsky, V.

    LEOPACK is yet another LEO satellite project which provides global integrated services for 'business' communications. It utilizes packet rather then circuit switching in both terrestrial and satellite chains as well as cellular approach for frequencies use. Original multiple access protocols and decentralized network control make it possible to organize regionally or logically independent and world-wide networks. Relatively small number of satellites (28) provides virtually global network coverage.

  16. Pancreatic Cancer Cell Exosome-Mediated Macrophage Reprogramming and the Role of MicroRNAs 155 and 125b2 Transfection using Nanoparticle Delivery Systems

    PubMed Central

    Su, Mei-Ju; Aldawsari, Hibah; Amiji, Mansoor

    2016-01-01

    Exosomes are nano-sized endosome-derived small intraluminal vesicles, which are important facilitators of intercellular communication by transporting contents, such as protein, mRNA, and microRNAs, between neighboring cells, such as in the tumor microenvironment. The purpose of this study was to understand the mechanisms of exosomes-mediated cellular communication between human pancreatic cancer (Panc-1) cells and macrophages (J771.A1) using a Transwell co-culture system. Following characterization of exosome-mediated cellular communication and pro-tumoral baseline M2 macrophage polarization, the Panc-1 cells were transfected with microRNA-155 (miR-155) and microRNA-125b-2 (miR-125b2) expressing plasmid DNA using hyaluronic acid-poly(ethylene imine)/hyaluronic acid-poly(ethylene glycol) (HA-PEI/HA-PEG) self-assembling nanoparticle-based non-viral vectors. Our results show that upon successful transfection of Panc-1 cells, the exosome content was altered leading to differential communication and reprogramming of the J774.A1 cells to an M1 phenotype. Based on these results, genetic therapies targeted towards selective manipulation of tumor cell-derived exosome content may be very promising for cancer therapy. PMID:27443190

  17. Propagation experiment of COMETS Ka/Q-band communication link for future satellite cellular system

    NASA Technical Reports Server (NTRS)

    Hase, Yoshihiro

    1995-01-01

    Mobile/Personal Satellite Communication Systems in L/S-bands are going into the operational phase. In the future, they will be operated in much higher frequency bands, for example in Ka-band, because the available bandwidth in L-band is limited. Systems with large on-board antennas in higher frequencies allow the same configuration as terrestrial cellular radio systems, since the on-board antennas will have many small spot beams. This may be true especially in a low earth orbit system such as Teledesic, which will use Ka-band. The most important parameter of Satellite Cellular may be cell size, that is, a diameter of the spot beam. A system designer needs the local correlation data in a cell and the size of the correlative area. On the other hand, the most significant difficulty of Ka and higher band systems is the countermeasure to rain attenuation. Many-cell systems can manage the limited power of on-board transponders by controlling output power of each beam depending on the rain attenuation of each cell. If the cell size is equal to the correlative area, the system can probably achieve the maximum performance. Propagation data of Ka and higher band obtained in the past shows a long term cumulative feature and link availability, but do not indicate the correlative area. The Japanese COMETS satellite, which will be launched in February 1997, has transponders in Ka and Q-band. The CRL is planning to measure the correlative area using 21 GHz and 44 GHz CW transmissions from the COMETS.

  18. Multistage Estimation Of Frequency And Phase

    NASA Technical Reports Server (NTRS)

    Kumar, Rajendra

    1991-01-01

    Conceptual two-stage software scheme serves as prototype of multistage scheme for digital estimation of phase, frequency, and rate of change of frequency ("Doppler rate") of possibly phase-modulated received sinusoidal signal in communication system in which transmitter and/or receiver traveling rapidly, accelerating, and/or jerking severely. Each additional stage of multistage scheme provides increasingly refined estimate of frequency and phase of signal. Conceived for use in estimating parameters of signals from spacecraft and high dynamic GPS signal parameters, also applicable, to terrestrial stationary/mobile (e.g., cellular radio) and land-mobile/satellite communication systems.

  19. Enhanced Communication Network Solution for Positive Train Control Implementation

    NASA Technical Reports Server (NTRS)

    Fatehi, M. T.; Simon, J.; Chang, W.; Chow, E. T.; Burleigh, S. C.

    2011-01-01

    The commuter and freight railroad industry is required to implement Positive Train Control (PTC) by 2015 (2012 for Metrolink), a challenging network communications problem. This paper will discuss present technologies developed by the National Aeronautics and Space Administration (NASA) to overcome comparable communication challenges encountered in deep space mission operations. PTC will be based on a new cellular wireless packet Internet Protocol (IP) network. However, ensuring reliability in such a network is difficult due to the "dead zones" and transient disruptions we commonly experience when we lose calls in commercial cellular networks. These disruptions make it difficult to meet PTC s stringent reliability (99.999%) and safety requirements, deployment deadlines, and budget. This paper proposes innovative solutions based on space-proven technologies that would help meet these challenges: (1) Delay Tolerant Networking (DTN) technology, designed for use in resource-constrained, embedded systems and currently in use on the International Space Station, enables reliable communication over networks in which timely data acknowledgments might not be possible due to transient link outages. (2) Policy-Based Management (PBM) provides dynamic management capabilities, allowing vital data to be exchanged selectively (with priority) by utilizing alternative communication resources. The resulting network may help railroads implement PTC faster, cheaper, and more reliably.

  20. DS-CDMA satellite diversity reception for personal satellite communication: Downlink performance analysis

    NASA Technical Reports Server (NTRS)

    DeGaudenzi, Riccardo; Giannetti, Filippo

    1995-01-01

    The downlink of a satellite-mobile personal communication system employing power-controlled Direct Sequence Code Division Multiple Access (DS-CDMA) and exploiting satellite-diversity is analyzed and its performance compared with a more traditional communication system utilizing single satellite reception. The analytical model developed has been thoroughly validated by means of extensive Monte Carlo computer simulations. It is shown how the capacity gain provided by diversity reception shrinks considerably in the presence of increasing traffic or in the case of light shadowing conditions. Moreover, the quantitative results tend to indicate that to combat system capacity reduction due to intra-system interference, no more than two satellites shall be active over the same region. To achieve higher system capacity, differently from terrestrial cellular systems, Multi-User Detection (MUD) techniques are likely to be required in the mobile user terminal, thus considerably increasing its complexity.

  1. 47 CFR 22.913 - Effective radiated power limits.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 22.913 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.913 Effective radiated power limits. The effective... such systems must not exceed 1000 Watts. The ERP of mobile transmitters and auxiliary test transmitters...

  2. Fast massive preventive security and information communication systems

    NASA Astrophysics Data System (ADS)

    Akopian, David; Chen, Philip; Miryakar, Susheel; Kumar, Abhinav

    2008-04-01

    We present a fast massive information communication system for data collection from distributive sources such as cell phone users. As a very important application one can mention preventive notification systems when timely notification and evidence communication may help to improve safety and security through wide public involvement by ensuring easy-to-access and easy-to-communicate information systems. The technology significantly simplifies the response to the events and will help e.g. special agencies to gather crucial information in time and respond as quickly as possible. Cellular phones are nowadays affordable for most of the residents and became a common personal accessory. The paper describes several ways to design such systems including existing internet access capabilities of cell phones or downloadable specialized software. We provide examples of such designs. The main idea is in structuring information in predetermined way and communicating data through a centralized gate-server which will automatically process information and forward it to a proper destination. The gate-server eliminates a need in knowing contact data and specific local community infrastructure. All the cell phones will have self-localizing capability according to FCC E911 mandate, thus the communicated information can be further tagged automatically by location and time information.

  3. The resolution of ambiguity as the basis for life: A cellular bridge between Western reductionism and Eastern holism.

    PubMed

    Torday, John S; Miller, William B

    2017-12-01

    Boundary conditions enable cellular life through negentropy, chemiosmosis, and homeostasis as identifiable First Principles of Physiology. Self-referential awareness of status arises from this organized state to sustain homeostatic imperatives. Preferred homeostatic status is dependent upon the appraisal of information and its communication. However, among living entities, sources of information and their dissemination are always imprecise. Consequently, living systems exist within an innate state of ambiguity. It is presented that cellular life and evolutionary development are a self-organizing cellular response to uncertainty in iterative conformity with its basal initiating parameters. Viewing the life circumstance in this manner permits a reasoned unification between Western rational reductionism and Eastern holism. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Smarter hospital communication: secure smartphone text messaging improves provider satisfaction and perception of efficacy, workflow.

    PubMed

    Przybylo, Jennifer A; Wang, Ange; Loftus, Pooja; Evans, Kambria H; Chu, Isabella; Shieh, Lisa

    2014-09-01

    Though current hospital paging systems are neither efficient (callbacks disrupt workflow), nor secure (pagers are not Health Insurance Portability and Accountability Act [HIPAA]-compliant), they are routinely used to communicate patient information. Smartphone-based text messaging is a potentially more convenient and efficient mobile alternative; however, commercial cellular networks are also not secure. To determine if augmenting one-way pagers with Medigram, a secure, HIPAA-compliant group messaging (HCGM) application for smartphones, could improve hospital team communication. Eight-week prospective, cluster-randomized, controlled trial Stanford Hospital Three inpatient medicine teams used the HCGM application in addition to paging, while two inpatient medicine teams used paging only for intra-team communication. Baseline and post-study surveys were collected from 22 control and 41 HCGM team members. When compared with paging, HCGM was rated significantly (P < 0.05) more effective in: (1) allowing users to communicate thoughts clearly (P = 0.010) and efficiently (P = 0.009) and (2) integrating into workflow during rounds (P = 0.018) and patient discharge (P = 0.012). Overall satisfaction with HCGM was significantly higher (P = 0.003). 85% of HCGM team respondents said they would recommend using an HCGM system on the wards. Smartphone-based, HIPAA-compliant group messaging applications improve provider perception of in-hospital communication, while providing the information security that paging and commercial cellular networks do not. © 2014 The Authors Journal of Hospital Medicine published by Wiley Periodicals, Inc. on behalf of Society of Hospital Medicine.

  5. Technical comparison of several global mobile satellite communications systems

    NASA Astrophysics Data System (ADS)

    Comparetto, Gary M.

    The era of satellite-based mobile satellite communications (MSC) systems started with the first MARISAT satellite which was launched into a geostationary orbit over the Pacific Ocean in 1976 to provide communications between ships and shore stations. The combination of high cost and unacceptably large equipment has kept the space-based MSC systems from appealing to the wider market of personal mobile communications. The progress made over the last ten years, however, in digital voice processing, satellite technology, and component miniaturization has resulted in the viability of satellite-based mobile satellite communications systems to meet the growing market in personal mobile communications using handsets similar to those currently in use with land-based cellular systems. Three of the more mature LEO/MEO satellite systems are addressed in this paper including GLOBALSTAR, Iridium, and Odyssey. The system architectures of each system are presented along with a description of the satellite and user handset designs and the multiaccess techniques employed. It will be shown that, although a number of similarities exist among the system addressed, each system is unique in a variety of significant design areas. It is concluded that the technical feasibility of satellite-based mobile satellite communications systems seems to be secure. It will be challenging, however, for the vendors to actually develop and deploy these systems in a cost effective, timely, and reliable way that meets a continually evolving set of requirements based upon a rapidly changing technology base.

  6. An optofluidic channel model for in vivo nanosensor networks in human blood

    NASA Astrophysics Data System (ADS)

    Johari, Pedram; Jornet, Josep M.

    2017-05-01

    In vivo Wireless Nanosensor Networks (iWNSNs) consist of nano-sized communicating devices with unprece- dented sensing and actuation capabilities, which are able to operate inside the human body. iWNSNs are a disruptive technology that enables the monitoring and control of biological processes at the cellular and sub- cellular levels. Compared to ex vivo measurements, which are conducted on samples extracted from the human body, iWNSNs can track (sub) cellular processes when and where they occur. Major progress in the field of na- noelectronics, nanophotonics and wireless communication is enabling the interconnection of nanosensors. Among others, plasmonic nanolasers with sub-micrometric footprint, plasmonic nano-antennas able to confine light in nanometric structures, and single-photon detectors with unrivaled sensitivity, enable the communication among implanted nanosensors in the near infrared and optical transmission windows. Motivated by these results, in this paper, an optofluidic channel model is developed to investigate the communication properties and temporal dynamics between a pair of in vivo nanosensors in the human blood. The developed model builds upon the authors' recent work on light propagation modeling through multi-layered single cells and cell assemblies and takes into account the geometric, electromagnetic and microfluidic properties of red blood cells in the human circulatory system. The proposed model guides the development of practical communication strategies among nanosensors, and paves the way through new nano-biosensing strategies able to identify diseases by detecting the slight changes in the channel impulse response, caused by either the change in shape of the blood cells or the presence of pathogens.

  7. 47 CFR 22.946 - Service commencement and construction systems.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    .... 22.946 Section 22.946 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.946 Service commencement and... telephone network (PSTN) and must be providing service to mobile stations operated by its subscribers and...

  8. Communication in critical care environments: mobile telephones improve patient care.

    PubMed

    Soto, Roy G; Chu, Larry F; Goldman, Julian M; Rampil, Ira J; Ruskin, Keith J

    2006-02-01

    Most hospital policies prohibiting the use of wireless devices cite reports of disruption of medical equipment by cellular telephones. There have been no studies to determine whether mobile telephones may have a beneficial impact on safety. At the 2003 meeting of the American Society of Anesthesiologists 7878 surveys were distributed to attendees. The five-question survey polled anesthesiologists regarding modes of communication used in the operating room/intensive care unit and experience with communications delays and medical errors. Survey reliability was verified using test-retest analysis and proportion agreement in a convenience sample of 17 anesthesiologists. Four-thousand-eighteen responses were received. The test-retest reliability of the survey instrument was excellent (Kappa = 0.75; 95% confidence interval, 0.56-0.94). Sixty-five percent of surveyed anesthesiologists reported using pagers as their primary mode of communications, whereas only 17% used cellular telephones. Forty-five percent of respondents who use pagers reported delays in communications compared with 31% of cellular telephone users. Cellular telephone use by anesthesiologists is associated with a reduction in the risk of medical error or injury resulting from communication delay (relative risk = 0.78; 95% confidence interval, 0.6234-0.9649). The small risks of electromagnetic interference between mobile telephones and medical devices should be weighed against the potential benefits of improved communication.

  9. The Globalstar mobile satellite system for worldwide personal communications

    NASA Astrophysics Data System (ADS)

    Wiedeman, Robert A.; Viterbi, Andrew J.

    Loral Aerospace Corporation along with Qualcomm Inc. have developed a satellite system which offers global mobile voice and data services to and from handheld and mobile user terminals with omni-directional antennas. By combining the use of low-earth orbit (LEO) satellites with existing terrestrial communications systems and innovative, highly efficient spread spectrum techniques, the Globalstar system provides users with low-cost, reliable communications throughout the world. The Globalstar space segment consists of a constellation of 48 LEO satellites in circular orbits with 750 NM (1389 km) altitude. Each satellite communicates with the mobile users via the satellite-user links and with gateway stations. The gateway stations handle the interface between the Globalstar network and the OSTN/PLMN systems. Globalstar transceivers are similar to currently proposed digital cellular telephones in size and have a serial number that will allow the end user to make and receive calls from or to that device anywhere in the world. The Globalstar system is designed to operate as a complement to existing local, long-distance, public, private and specialized telecommunications networks. Service is primarily designed to serve the rural and thin route communications needs of consumers, government users, and private networks.

  10. The Globalstar mobile satellite system for worldwide personal communications

    NASA Technical Reports Server (NTRS)

    Wiedeman, Robert A.; Viterbi, Andrew J.

    1993-01-01

    Loral Aerospace Corporation along with Qualcomm Inc. have developed a satellite system which offers global mobile voice and data services to and from handheld and mobile user terminals with omni-directional antennas. By combining the use of low-earth orbit (LEO) satellites with existing terrestrial communications systems and innovative, highly efficient spread spectrum techniques, the Globalstar system provides users with low-cost, reliable communications throughout the world. The Globalstar space segment consists of a constellation of 48 LEO satellites in circular orbits with 750 NM (1389 km) altitude. Each satellite communicates with the mobile users via the satellite-user links and with gateway stations. The gateway stations handle the interface between the Globalstar network and the OSTN/PLMN systems. Globalstar transceivers are similar to currently proposed digital cellular telephones in size and have a serial number that will allow the end user to make and receive calls from or to that device anywhere in the world. The Globalstar system is designed to operate as a complement to existing local, long-distance, public, private and specialized telecommunications networks. Service is primarily designed to serve the rural and thin route communications needs of consumers, government users, and private networks.

  11. Performance of high-temperature superconducting band-pass filters with high selectivity for base transceiver applications of digital cellular communication systems

    NASA Astrophysics Data System (ADS)

    Kwak, J. S.; Lee, J. H.; Kim, C. O.; Hong, J. P.; Han, S. K.; Char, K.

    2002-07-01

    Highly selective high-temperature superconducting band-pass filters based on spiral meander line structures have been developed for base transceiver station applications of digital cellular communication systems. The filter comprised 12-pole microstrip line resonators with a circuit size of 0.5 × 17 × 41 mm3. The filter was designed to have a bandwidth of 25 MHz at a centre frequency of 834 MHz. Particularly, the physical size of each resonator was chosen not only to reduce far-field radiation, but also to have reasonable tunability in the filter. Device characteristics exhibited a low insertion loss of 0.4 dB with a 0.2 dB ripple and a return loss better than 10 dB in the pass-band at 65 K. The out-of-band signals were attenuated better than 60 dB at about 3.5 MHz from the lower band edge, and 3.8 MHz from the higher band edge.

  12. Chloroplast-to-nucleus communication

    PubMed Central

    Chan, Kai Xun; Crisp, Peter Alexander; Estavillo, Gonzalo Martin

    2010-01-01

    In order for plant cells to function efficiently under different environmental conditions, chloroplastic processes have to be tightly regulated by the nucleus. It is widely believed that there is inter-organelle communication from the chloroplast to the nucleus, called retrograde signaling. Although some pathways of communication have been identified, the actual signals that move between the two cellular compartments are largely unknown. This review provides an overview of retrograde signaling including its importance to the cell, candidate signals, recent advances and current experimental systems. In addition, we highlight the potential of using drought stress as a model for studying retrograde signaling. PMID:21512326

  13. The Device Centric Communication System for 5G Networks

    NASA Astrophysics Data System (ADS)

    Biswash, S. K.; Jayakody, D. N. K.

    2017-01-01

    The Fifth Generation Communication (5G) networks have several functional features such as: Massive Multiple Input and Multiple Output (MIMO), Device centric data and voice support, Smarter-device communications, etc. The objective for 5G networks is to gain the 1000x more throughput, 10x spectral efficiency, 100 x more energy efficiency than existing technologies. The 5G system will provide the balance between the Quality of Experience (QoE) and the Quality of Service (QoS), without compromising the user benefit. The data rate has been the key metric for wireless QoS; QoE deals with the delay and throughput. In order to realize a balance between the QoS and QoE, we propose a cellular Device centric communication methodology for the overlapping network coverage area in the 5G communication system. The multiple beacon signals mobile tower refers to an overlapping network area, and a user must be forwarded to the next location area. To resolve this issue, we suggest the user centric methodology (without Base Station interface) to handover the device in the next area, until the users finalize the communication. The proposed method will reduce the signalling cost and overheads for the communication.

  14. Study on the spectral efficiency of SFH-GMSK in land mobile telephone communication by direct simulation

    NASA Technical Reports Server (NTRS)

    Bao, H.; Kwatra, S. C.; Kim, Junghwan; Stevens, G. H.

    1990-01-01

    A spread spectrum system, slow frequency hopping with GMSK (Gaussian minimum shift keying) modulation (SFH-GMSK), is proposed for mobile telephone communications. The system performance is evaluated using computer simulation and is compared with an unspread system. Results show that under multipath fading conditions, when the signal-to-noise ratio (SNR) is greater than 15 dB, slow frequency hopping gives some bit error rate improvement over the unspread system. Theoretical predictions indicate that a system efficiency of 20-65 users per cell can be achieved in the cellular configuration. Joint use of SFH-GMSK and FM is also investigated. It is shown that FM interference can cause serious degradation to the SFH-GMSK performance.

  15. ACTS Aeronautical Terminal Experiment (AERO-X)

    NASA Technical Reports Server (NTRS)

    1995-01-01

    During the summer of 1994, the performance of an experimental mobile satellite communication system was demonstrated. Using the Advanced Communications Technology Satellite (ACTS) and the ACTS Mobile Terminal (AMT), the system demonstrated an active Monolithic Microwave Integrated Circuit (MMIC) phased-array antenna system. The antenna system was installed onboard one of NASA Lewis Research Center's research aircraft, a Learjet Model 25. It proved the viability of in-flight satellite communications services via small, flush, mountable electronic phased-array antennas. The overall system setup for the ACTS Aeronautical Terminal Experiment (AERO-X) is illustrated. The Link Evaluation Terminal (LET) at Lewis in Cleveland, Ohio, interfaced with fixed-AMT equipment, providing a seamless connection with the Public Service Telephone Network. As the Learjet was flown over several major cities across the U.S., this demonstration system allowed passengers onboard to make telephone calls as if they were using a cellular system. ACTS was operated in its microwave switch matrix mode with a spot beam for the Learjet and another spot beam dedicated to the LET.

  16. Ultralife's polymer electrolyte rechargeable lithium-ion batteries for use in the mobile electronics industry

    NASA Astrophysics Data System (ADS)

    Cuellar, Edward A.; Manna, Michael E.; Wise, Ralph D.; Gavrilov, Alexei B.; Bastian, Matthew J.; Brey, Rufus M.; DeMatteis, Jeffrey

    Ultralife Polymer™ brand batteries for cellular phones as made by Nokia Mobile Phones Incorporated were introduced in July 2000. Characteristics of the UBC443483 cell and UB750N battery are described and related to the power and battery requirements of these cellular phones and chargers. Current, power, and pulse capability are presented as functions of temperature, depth of discharge, and storage at the cell level. Safety protection devices and chargers are discussed at the battery pack level, as well as performance in cellular phones under various wireless communication protocols. Performance is competitive with liquid lithium-ion systems while offering opportunity for non-traditional form factors.

  17. Cellular computational generalized neuron network for frequency situational intelligence in a multi-machine power system.

    PubMed

    Wei, Yawei; Venayagamoorthy, Ganesh Kumar

    2017-09-01

    To prevent large interconnected power system from a cascading failure, brownout or even blackout, grid operators require access to faster than real-time information to make appropriate just-in-time control decisions. However, the communication and computational system limitations of currently used supervisory control and data acquisition (SCADA) system can only deliver delayed information. However, the deployment of synchrophasor measurement devices makes it possible to capture and visualize, in near-real-time, grid operational data with extra granularity. In this paper, a cellular computational network (CCN) approach for frequency situational intelligence (FSI) in a power system is presented. The distributed and scalable computing unit of the CCN framework makes it particularly flexible for customization for a particular set of prediction requirements. Two soft-computing algorithms have been implemented in the CCN framework: a cellular generalized neuron network (CCGNN) and a cellular multi-layer perceptron network (CCMLPN), for purposes of providing multi-timescale frequency predictions, ranging from 16.67 ms to 2 s. These two developed CCGNN and CCMLPN systems were then implemented on two different scales of power systems, one of which installed a large photovoltaic plant. A real-time power system simulator at weather station within the Real-Time Power and Intelligent Systems (RTPIS) laboratory at Clemson, SC, was then used to derive typical FSI results. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Distributed sensor networks: a cellular nonlinear network perspective.

    PubMed

    Haenggi, Martin

    2003-12-01

    Large-scale networks of integrated wireless sensors become increasingly tractable. Advances in hardware technology and engineering design have led to dramatic reductions in size, power consumption, and cost for digital circuitry, and wireless communications. Networking, self-organization, and distributed operation are crucial ingredients to harness the sensing, computing, and computational capabilities of the nodes into a complete system. This article shows that those networks can be considered as cellular nonlinear networks (CNNs), and that their analysis and design may greatly benefit from the rich theoretical results available for CNNs.

  19. Ethical Decision Making, Therapeutic Boundaries, and Communicating Using Online Technology and Cellular Phones

    ERIC Educational Resources Information Center

    Yonan, Jesay; Bardick, Angela D.; Willment, Jo-Anne H.

    2011-01-01

    Cellular telephones and social networking sites pose new challenges to the maintenance of therapeutic boundaries. One such difficulty is the possible development of dual relationships between clients and counselling professionals as a result of communicating by these means. Most regulatory bodies advise professional counsellors and psychologists…

  20. 76 FR 75492 - Atlantic Highly Migratory Species; Vessel Monitoring Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-02

    ... and fishing gears possessed to be made by phone. Some small fishing vessels remain within cell phone... terminals represent a more reliable means of communication than cellular phones because they use satellites rather than cell towers as the principle means of transmitting data. Furthermore, vessels need to provide...

  1. Hardwiring stem cell communication through tissue structure

    PubMed Central

    Xin, Tianchi; Greco, Valentina; Myung, Peggy

    2016-01-01

    Adult stem cells across diverse organs self-renew and differentiate to maintain tissue homeostasis. How stem cells receive input to preserve tissue structure and function largely relies on their communication with surrounding cellular and non-cellular elements. As such, how tissues are organized and patterned not only reflects organ function but also inherently hardwires networks of communication between stem cells and their environment to direct tissue homeostasis and injury repair. This review highlights how different methods of stem cell communication reflect the unique organization and function of diverse tissues. PMID:26967287

  2. 47 CFR 22.911 - Cellular geographic service area.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 2 2012-10-01 2012-10-01 false Cellular geographic service area. 22.911 Section 22.911 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.911 Cellular geographic service area. The...

  3. Virtualized MME Design for IoT Support in 5G Systems.

    PubMed

    Andres-Maldonado, Pilar; Ameigeiras, Pablo; Prados-Garzon, Jonathan; Ramos-Munoz, Juan Jose; Lopez-Soler, Juan Manuel

    2016-08-22

    Cellular systems are recently being considered an option to provide support to the Internet of Things (IoT). To enable this support, the 3rd Generation Partnership Project (3GPP) has introduced new procedures specifically targeted for cellular IoT. With one of these procedures, the transmissions of small and infrequent data packets from/to the devices are encapsulated in signaling messages and sent through the control plane. However, these transmissions from/to a massive number of devices may imply a major increase of the processing load on the control plane entities of the network and in particular on the Mobility Management Entity (MME). In this paper, we propose two designs of an MME based on Network Function Virtualization (NFV) that aim at facilitating the IoT support. The first proposed design partially separates the processing resources dedicated to each traffic class. The second design includes traffic shaping to control the traffic of each class. We consider three classes: Mobile Broadband (MBB), low latency Machine to Machine communications (lM2M) and delay-tolerant M2M communications. Our proposals enable reducing the processing resources and, therefore, the cost. Additionally, results show that the proposed designs lessen the impact between classes, so they ease the compliance of the delay requirements of MBB and lM2M communications.

  4. Path loss analysis in millimeter wave cellular systems for urban mobile communications

    NASA Astrophysics Data System (ADS)

    Rajagopalan, Ramesh; Hoffman, Mitchell

    2016-09-01

    The proliferation in the number of mobile devices and developments in cellular technology has led to an ever increasing demand for mobile data. The global bandwidth shortage facing wireless carriers today has motivated research for fifth generation (5G) cellular systems. In recent years, millimeter wave (mmW) frequencies between 30 and 300 GHz are being considered as a promising technology for 5G systems. Such systems can offer superior user experience by providing data rates that exceed one Gigabit per second and latencies lower than a millisecond. However, there is little research about cellular mmW propagation in densely populated urban environments. Understanding the radio channel is a primary requirement for optimal design of mmW systems. Radio propagation in mmW systems faces significant challenges due to rapidly varying channel conditions and intermittent connectivity. In this paper, we study the propagation of mmW spectrum in an urban environment. We use a statistical model to simulate an urban environment with diverse building distributions. We perform extensive simulations to analyze the path loss behavior for both line of sight (LOS) and non line of sight (NLOS) conditions for 28 GHZ and 73 GHZ mmW frequencies. We observe that the path loss approximates a logarithmic fit for both LOS and NLOS environments. Our simulations show that the omnidirectional free space path loss is approximately 30 dB higher for mmW systems compared to current 3G PP cellular systems. To address this challenge, we propose using highly directional horn antennas with beam forming for reducing the path loss.

  5. Cellular automata with object-oriented features for parallel molecular network modeling.

    PubMed

    Zhu, Hao; Wu, Yinghui; Huang, Sui; Sun, Yan; Dhar, Pawan

    2005-06-01

    Cellular automata are an important modeling paradigm for studying the dynamics of large, parallel systems composed of multiple, interacting components. However, to model biological systems, cellular automata need to be extended beyond the large-scale parallelism and intensive communication in order to capture two fundamental properties characteristic of complex biological systems: hierarchy and heterogeneity. This paper proposes extensions to a cellular automata language, Cellang, to meet this purpose. The extended language, with object-oriented features, can be used to describe the structure and activity of parallel molecular networks within cells. Capabilities of this new programming language include object structure to define molecular programs within a cell, floating-point data type and mathematical functions to perform quantitative computation, message passing capability to describe molecular interactions, as well as new operators, statements, and built-in functions. We discuss relevant programming issues of these features, including the object-oriented description of molecular interactions with molecule encapsulation, message passing, and the description of heterogeneity and anisotropy at the cell and molecule levels. By enabling the integration of modeling at the molecular level with system behavior at cell, tissue, organ, or even organism levels, the program will help improve our understanding of how complex and dynamic biological activities are generated and controlled by parallel functioning of molecular networks. Index Terms-Cellular automata, modeling, molecular network, object-oriented.

  6. Chloroplast-to-nucleus communication: current knowledge, experimental strategies and relationship to drought stress signaling.

    PubMed

    Chan, Kai Xun; Crisp, Peter Alexander; Estavillo, Gonzalo Martin; Pogson, Barry James

    2010-12-01

    In order for plant cells to function efficiently under different environmental conditions, chloroplastic processes have to be tightly regulated by the nucleus. It is widely believed that there is inter-organelle communication from the chloroplast to the nucleus, called retrograde signaling. Although some pathways of communication have been identified, the actual signals that move between the two cellular compartments are largely unknown. This review provides an overview of retrograde signaling including its importance to the cell, candidate signals, recent advances, and current experimental systems. In addition, we highlight the potential of using drought stress as a model for studying retrograde signaling.

  7. 47 CFR 22.905 - Channels for cellular service.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Channels for cellular service. 22.905 Section 22.905 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.905 Channels for cellular service. The following...

  8. 47 CFR 22.905 - Channels for cellular service.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Channels for cellular service. 22.905 Section 22.905 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.905 Channels for cellular service. The following...

  9. 47 CFR 22.917 - Emission limitations for cellular equipment.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Emission limitations for cellular equipment. 22.917 Section 22.917 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.917 Emission limitations for cellular...

  10. 47 CFR 22.905 - Channels for cellular service.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Channels for cellular service. 22.905 Section 22.905 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.905 Channels for cellular service. The following...

  11. 47 CFR 22.917 - Emission limitations for cellular equipment.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Emission limitations for cellular equipment. 22.917 Section 22.917 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.917 Emission limitations for cellular...

  12. Performance Evaluation of Analog Beamforming with Hardware Impairments for mmW Massive MIMO Communication in an Urban Scenario.

    PubMed

    Gimenez, Sonia; Roger, Sandra; Baracca, Paolo; Martín-Sacristán, David; Monserrat, Jose F; Braun, Volker; Halbauer, Hardy

    2016-09-22

    The use of massive multiple-input multiple-output (MIMO) techniques for communication at millimeter-Wave (mmW) frequency bands has become a key enabler to meet the data rate demands of the upcoming fifth generation (5G) cellular systems. In particular, analog and hybrid beamforming solutions are receiving increasing attention as less expensive and more power efficient alternatives to fully digital precoding schemes. Despite their proven good performance in simple setups, their suitability for realistic cellular systems with many interfering base stations and users is still unclear. Furthermore, the performance of massive MIMO beamforming and precoding methods are in practice also affected by practical limitations and hardware constraints. In this sense, this paper assesses the performance of digital precoding and analog beamforming in an urban cellular system with an accurate mmW channel model under both ideal and realistic assumptions. The results show that analog beamforming can reach the performance of fully digital maximum ratio transmission under line of sight conditions and with a sufficient number of parallel radio-frequency (RF) chains, especially when the practical limitations of outdated channel information and per antenna power constraints are considered. This work also shows the impact of the phase shifter errors and combiner losses introduced by real phase shifter and combiner implementations over analog beamforming, where the former ones have minor impact on the performance, while the latter ones determine the optimum number of RF chains to be used in practice.

  13. Integration between terrestrial-based and satellite-based land mobile communications systems

    NASA Technical Reports Server (NTRS)

    Arcidiancono, Antonio

    1990-01-01

    A survey is given of several approaches to improving the performance and marketability of mobile satellite systems (MSS). The provision of voice/data services in the future regional European Land Mobile Satellite System (LMSS), network integration between the Digital Cellular Mobile System (GSM) and LMSS, the identification of critical areas for the implementation of integrated GSM/LMSS areas, space segment scenarios, LMSS for digital trunked private mobile radio (PMR) services, and code division multiple access (CDMA) techniques for a terrestrial/satellite system are covered.

  14. Multicellular Computing Using Conjugation for Wiring

    PubMed Central

    Goñi-Moreno, Angel; Amos, Martyn; de la Cruz, Fernando

    2013-01-01

    Recent efforts in synthetic biology have focussed on the implementation of logical functions within living cells. One aim is to facilitate both internal “re-programming” and external control of cells, with potential applications in a wide range of domains. However, fundamental limitations on the degree to which single cells may be re-engineered have led to a growth of interest in multicellular systems, in which a “computation” is distributed over a number of different cell types, in a manner analogous to modern computer networks. Within this model, individual cell type perform specific sub-tasks, the results of which are then communicated to other cell types for further processing. The manner in which outputs are communicated is therefore of great significance to the overall success of such a scheme. Previous experiments in distributed cellular computation have used global communication schemes, such as quorum sensing (QS), to implement the “wiring” between cell types. While useful, this method lacks specificity, and limits the amount of information that may be transferred at any one time. We propose an alternative scheme, based on specific cell-cell conjugation. This mechanism allows for the direct transfer of genetic information between bacteria, via circular DNA strands known as plasmids. We design a multi-cellular population that is able to compute, in a distributed fashion, a Boolean XOR function. Through this, we describe a general scheme for distributed logic that works by mixing different strains in a single population; this constitutes an important advantage of our novel approach. Importantly, the amount of genetic information exchanged through conjugation is significantly higher than the amount possible through QS-based communication. We provide full computational modelling and simulation results, using deterministic, stochastic and spatially-explicit methods. These simulations explore the behaviour of one possible conjugation-wired cellular computing system under different conditions, and provide baseline information for future laboratory implementations. PMID:23840385

  15. Cost Consideration for Future Communications Satellite

    NASA Astrophysics Data System (ADS)

    Iida, Takashi

    2002-01-01

    This paper discusses the cost driving factors of the future communications satellite rather than discussing its cost itself directly, in terms of development period of time, services, and R&D by government. In the first, a period of time for development of a communications system is discussed in comparison of satellite communications system with a terrestrial communications system. Generally speaking, the terrestrial communications system is developed in a short period. Especially, the recent network related IT technology changes very rapidly, like so-called as "Dog Year". On the other hand, it takes a long time, more than several years, to develop a satellite communications system. This paper will discuss this time period of development is how to influence the system realization in various cases. In the second, the service related cost is discussed. First, a mobile communications satellite system is considered as an example. The tremendous penetration speed of the terrestrial cellular phones prevents from the success of the mobile satellite communications system. The success of the mobile satellite communications system depends on how early and user friendly to develop its user terminals. Second, the broadcasting service is described as a successful example. It is described that the satellite broadcasting has a very competitive advantage to the terrestrial broadcasting service from the cost point of view. Finally, the cost of the technology R&D for the future communication satellite by the government is discussed. A model of the future communications satellite for next 30 years has been proposed(1)(2). As an example, this paper estimates the satellite cost of the 60 Gbps range of capacity which is called as 1.5G satellite, where the capacity of the second generation Internet satellite (2G) is 50-500 Gbps per satellite. In the paper, the R&D plan of the future communications satellite will be discussed as a next R&D project to the first generation Internet satellite from a cost point of view. References (1)T.Iida and Y.Suzuki: "Satellite Communications R&D for Next 30 Years", 19th AIAA (2)T.Iida, Y.Suzuki and A.Akaishi: "Satellite Communications R&D for Next 30 Years:

  16. Rational Design of Semiconductor Nanostructures for Functional Subcellular Interfaces.

    PubMed

    Parameswaran, Ramya; Tian, Bozhi

    2018-05-15

    One of the fundamental questions guiding research in the biological sciences is how cellular systems process complex physical and environmental cues and communicate with each other across multiple length scales. Importantly, aberrant signal processing in these systems can lead to diseases that can have devastating impacts on human lives. Biophysical studies in the past several decades have demonstrated that cells can respond to not only biochemical cues but also mechanical and electrical ones. Thus, the development of new materials that can both sense and modulate all of these pathways is necessary. Semiconducting nanostructures are an emerging class of discovery platforms and tools that can push the limits of our ability to modulate and sense biological behaviors for both fundamental research and clinical applications. These materials are of particular interest for interfacing with cellular systems due to their matched dimension with subcellular components (e.g., cytoskeletal filaments), and easily tunable properties in the electrical, optical and mechanical regimes. Rational design via traditional or new approaches, such as nanocasting and mesoscale chemical lithography, can allow us to control micro- and nanoscale features in nanowires to achieve new biointerfaces. Both processes endogenous to the target cell and properties of the material surface dictate the character of these interfaces. In this Account, we focus on (1) approaches for the rational design of semiconducting nanowires that exhibit unique structures for biointerfaces, (2) recent fundamental discoveries that yield robust biointerfaces at the subcellular level, (3) intracellular electrical and mechanical sensing, and (4) modulation of cellular behaviors through material topography and remote physical stimuli. In the first section, we discuss new approaches for the synthetic control of micro- and nanoscale features of these materials. In the second section, we focus on achieving biointerfaces with these rationally designed materials either intra- or extracellularly. We last delve into the use of these materials in sensing mechanical forces and electrical signals in various cellular systems as well as in instructing cellular behaviors. Future research in this area may shift the paradigm in fundamental biophysical research and biomedical applications through (1) the design and synthesis of new semiconductor-based materials and devices that interact specifically with targeted cells, (2) the clarification of many developmental, physiological, and anatomical aspects of cellular communications, (3) an understanding of how signaling between cells regulates synaptic development (e.g., information like this would offer new insight into how the nervous system works and provide new targets for the treatment of neurological diseases), (4) and the creation of new cellular materials that have the potential to open up completely new areas of application, such as in hybrid information processing systems.

  17. Power attenuation characteristics as switch-over criterion in personal satellite mobile communications

    NASA Technical Reports Server (NTRS)

    Castro, Jonathan P.

    1993-01-01

    A third generation mobile system intends to support communications in all environments (i.e., outdoors, indoors at home or office and when moving). This system will integrate services that are now available in architectures such as cellular, cordless, mobile data networks, paging, including satellite services to rural areas. One way through which service integration will be made possible is by supporting a hierarchical cellular structure based on umbrella cells, macro cells, micro and pico cells. In this type of structure, satellites are part of the giant umbrella cells allowing continuous global coverage, the other cells belong to cities, neighborhoods, and buildings respectively. This does not necessarily imply that network operation of terrestrial and satellite segments interconnect to enable roaming and spectrum sharing. However, the cell concept does imply hand-off between different cell types, which may involve change of frequency. Within this propsective, the present work uses power attenuation characteristics to determine a dynamic criterion that allows smooth transition from space to terrestrial networks. The analysis includes a hybrid channel that combines Rician, Raleigh and Log Normal fading characteristics.

  18. Information transmission in microbial and fungal communication: from classical to quantum.

    PubMed

    Majumdar, Sarangam; Pal, Sukla

    2018-06-01

    Microbes have their own communication systems. Secretion and reception of chemical signaling molecules and ion-channels mediated electrical signaling mechanism are yet observed two special ways of information transmission in microbial community. In this article, we address the aspects of various crucial machineries which set the backbone of microbial cell-to-cell communication process such as quorum sensing mechanism (bacterial and fungal), quorum sensing regulated biofilm formation, gene expression, virulence, swarming, quorum quenching, role of noise in quorum sensing, mathematical models (therapy model, evolutionary model, molecular mechanism model and many more), synthetic bacterial communication, bacterial ion-channels, bacterial nanowires and electrical communication. In particular, we highlight bacterial collective behavior with classical and quantum mechanical approaches (including quantum information). Moreover, we shed a new light to introduce the concept of quantum synthetic biology and possible cellular quantum Turing test.

  19. Biomimetric sentinel reef structures for optical sensing and communications

    NASA Astrophysics Data System (ADS)

    Fries, David; Hutcheson, Tim; Josef, Noam; Millie, David; Tate, Connor

    2017-05-01

    Traditional artificial reef structures are designed with uniform cellular architectures and topologies and do not mimic natural reef forms. Strings and ropes are a proven, common fisheries and mariculture construction element throughout the world and using them as artificial reef scaffolding can enable a diversity of ocean sensing, communications systems including the goal of sentinel reefs. The architecture and packaging of electronics is key to enabling such structures and systems. The distributed sensor reef concept leads toward a demonstrable science-engineering-informed framework for 3D smart habitat designs critical to stock fish development and coastal monitoring and protection. These `nature-inspired' reef infrastructures, can enable novel instrumented `reef observatories' capable of collecting real-time ecosystem data. Embedding lighting and electronic elements into artificial reef systems are the first systems conceptualized. This approach of bringing spatial light to the underwater world for optical sensing, communication and even a new breed of underwater robotic vehicle is an interdisciplinary research activity which integrates principles of electronic packaging, and ocean technology with art/design.

  20. Concept and implementation of the Globalstar mobile satellite system

    NASA Technical Reports Server (NTRS)

    Schindall, Joel

    1995-01-01

    Globalstar is a satellite-based mobile communications system which provides quality wireless communications (voice and/or data) anywhere in the world except the polar regions. The Globalstar system concept is based upon technological advancements in Low Earth Orbit (LEO) satellite technology and in cellular telephone technology, including the commercial application of Code Division Multiple Access (CDMA) technologies. The Globalstar system uses elements of CDMA and Frequency Division Multiple Access (FDMA), combined with satellite Multiple Beam Antenna (MBA) technology and advanced variable-rate vocoder technology to arrive at one of the most efficient modulation and multiple access systems ever proposed for a satellite communications system. The technology used in Globalstar includes the following techniques in obtaining high spectral efficiency and affordable cost per channel: (1) CDMA modulation with efficient power control; (2) high efficiency vocoder with voice activity factor; (3) spot beam antenna for increased gain and frequency reuse; (4) weighted satellite antenna gain for broad geographic coverage; (5) multisatellite user links (diversity) to enhance communications reliability; and (6) soft hand-off between beams and satellites. Initial launch is scheduled in 1997 and the system is scheduled to be operational in 1998. The Globalstar system utilizes frequencies in L-, S- and C-bands which have the potential to offer worldwide availability with authorization by the appropriate regulatory agencies.

  1. Characteristics of Middle School Students Learning Actions in Outdoor Mathematical Activities with the Cellular Phone

    ERIC Educational Resources Information Center

    Daher, Wajeeh; Baya'a, Nimer

    2012-01-01

    Learning in the cellular phone environment enables utilizing the multiple functions of the cellular phone, such as mobility, availability, interactivity, verbal and voice communication, taking pictures or recording audio and video, measuring time and transferring information. These functions together with mathematics-designated cellular phone…

  2. Stochastic simulations of a synthetic bacteria-yeast ecosystem

    PubMed Central

    2012-01-01

    Background The field of synthetic biology has greatly evolved and numerous functions can now be implemented by artificially engineered cells carrying the appropriate genetic information. However, in order for the cells to robustly perform complex or multiple tasks, co-operation between them may be necessary. Therefore, various synthetic biological systems whose functionality requires cell-cell communication are being designed. These systems, microbial consortia, are composed of engineered cells and exhibit a wide range of behaviors. These include yeast cells whose growth is dependent on one another, or bacteria that kill or rescue each other, synchronize, behave as predator-prey ecosystems or invade cancer cells. Results In this paper, we study a synthetic ecosystem comprising of bacteria and yeast that communicate with and benefit from each other using small diffusible molecules. We explore the behavior of this heterogeneous microbial consortium, composed of Saccharomyces cerevisiae and Escherichia coli cells, using stochastic modeling. The stochastic model captures the relevant intra-cellular and inter-cellular interactions taking place in and between the eukaryotic and prokaryotic cells. Integration of well-characterized molecular regulatory elements into these two microbes allows for communication through quorum sensing. A gene controlling growth in yeast is induced by bacteria via chemical signals and vice versa. Interesting dynamics that are common in natural ecosystems, such as obligatory and facultative mutualism, extinction, commensalism and predator-prey like dynamics are observed. We investigate and report on the conditions under which the two species can successfully communicate and rescue each other. Conclusions This study explores the various behaviors exhibited by the cohabitation of engineered yeast and bacterial cells. The way that the model is built allows for studying the dynamics of any system consisting of two species communicating with one another via chemical signals. Therefore, key information acquired by our model may potentially drive the experimental design of various synthetic heterogeneous ecosystems. PMID:22672814

  3. Managing healthcare information using short message service (SMS) in wireless broadband networks

    NASA Astrophysics Data System (ADS)

    Documet, Jorge; Tsao, Sinchai; Documet, Luis; Liu, Brent J.; Zhou, Zheng; Joseph, Anika O.

    2007-03-01

    Due to the ubiquity of cell phones, SMS (Short Message Service) has become an ideal means to wirelessly manage a Healthcare environment and in particular PACS (Picture Archival and Communications System) data. SMS is a flexible and mobile method for real-time access and control of Healthcare information systems such as HIS (Hospital Information System) or PACS. Unlike conventional wireless access methods, SMS' mobility is not limited by the presence of a WiFi network or any other localized signal. It provides a simple, reliable yet flexible method to communicate with an information system. In addition, SMS services are widely available for low costs from cellular phone service providers and allows for more mobility than other services such as wireless internet. This paper aims to describe a use case of SMS as a means of remotely communicating with a PACS server. Remote access to a PACS server and its Query-Retrieve services allows for a more convenient, flexible and streamlined radiology workflow. Wireless access methods such as SMS will increase dedicated PACS workstation availability for more specialized DICOM (Digital Imaging and Communications in Medicine) workflow management. This implementation will address potential security, performance and cost issues of applying SMS as part of a healthcare information management system. This is in an effort to design a wireless communication system with optimal mobility and flexibility at minimum material and time costs.

  4. Exosomes and nanotubes: control of immune cell communication

    PubMed Central

    McCoy-Simandle, Kessler; Hanna, Samer J.; Cox, Dianne

    2015-01-01

    Cell-cell communication is critical to coordinate the activity and behavior of a multicellular organism. The cells of the immune system not only must communicate with similar cells, but also with many other cell types in the body. Therefore, the cells of the immune system have evolved multiple ways to communicate. Exosomes and tunneling nanotubes (TNTs) are two means of communication used by immune cells that contribute to immune functions. Exosomes are small membrane vesicles secreted by most cell types that can mediate intercellular communication and in the immune system they are proposed to play a role in antigen presentation and modulation of gene expression. TNTs are membranous structures that mediate direct cell-cell contact over several cell diameters in length (and possibly longer) and facilitate the interaction and/or the transfer of signals, material and other cellular organelles between connected cells. Recent studies have revealed additional, but sometimes conflicting, structural and functional features of both exosomes and TNTs. Despite the new and exciting information in exosome and TNT composition, origin and in vitro function, biologically significant functions are still being investigated and determined. In this review, we discuss the current field regarding exosomes and TNTs in immune cells providing evaluation and perspectives of the current literature. PMID:26704468

  5. Virtualized MME Design for IoT Support in 5G Systems

    PubMed Central

    Andres-Maldonado, Pilar; Ameigeiras, Pablo; Prados-Garzon, Jonathan; Ramos-Munoz, Juan Jose; Lopez-Soler, Juan Manuel

    2016-01-01

    Cellular systems are recently being considered an option to provide support to the Internet of Things (IoT). To enable this support, the 3rd Generation Partnership Project (3GPP) has introduced new procedures specifically targeted for cellular IoT. With one of these procedures, the transmissions of small and infrequent data packets from/to the devices are encapsulated in signaling messages and sent through the control plane. However, these transmissions from/to a massive number of devices may imply a major increase of the processing load on the control plane entities of the network and in particular on the Mobility Management Entity (MME). In this paper, we propose two designs of an MME based on Network Function Virtualization (NFV) that aim at facilitating the IoT support. The first proposed design partially separates the processing resources dedicated to each traffic class. The second design includes traffic shaping to control the traffic of each class. We consider three classes: Mobile Broadband (MBB), low latency Machine to Machine communications (lM2M) and delay-tolerant M2M communications. Our proposals enable reducing the processing resources and, therefore, the cost. Additionally, results show that the proposed designs lessen the impact between classes, so they ease the compliance of the delay requirements of MBB and lM2M communications. PMID:27556468

  6. 47 CFR 90.619 - Operations within the U.S./Mexico and U.S./Canada border areas.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 6 where high density cellular systems are prohibited are all frequencies that are primary to Canada..../Canada border areas. 90.619 Section 90.619 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED... Use of Frequencies in the 806-824, 851-869, 896-901, and 935-940 MHz Bands Policies Governing the...

  7. 47 CFR 90.619 - Operations within the U.S./Mexico and U.S./Canada border areas.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 6 where high density cellular systems are prohibited are all frequencies that are primary to Canada..../Canada border areas. 90.619 Section 90.619 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED... Use of Frequencies in the 806-824, 851-869, 896-901, and 935-940 MHz Bands Policies Governing the...

  8. 47 CFR 90.619 - Operations within the U.S./Mexico and U.S./Canada border areas.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 6 where high density cellular systems are prohibited are all frequencies that are primary to Canada..../Canada border areas. 90.619 Section 90.619 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED... Use of Frequencies in the 806-824, 851-869, 896-901, and 935-940 MHz Bands Policies Governing the...

  9. 47 CFR 90.619 - Operations within the U.S./Mexico and U.S./Canada border areas.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 6 where high density cellular systems are prohibited are all frequencies that are primary to Canada..../Canada border areas. 90.619 Section 90.619 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED... Use of Frequencies in the 806-824, 851-869, 896-901, and 935-940 MHz Bands Policies Governing the...

  10. 47 CFR 90.619 - Operations within the U.S./Mexico and U.S./Canada border areas.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 6 where high density cellular systems are prohibited are all frequencies that are primary to Canada..../Canada border areas. 90.619 Section 90.619 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED... Use of Frequencies in the 806-824, 851-869, 896-901, and 935-940 MHz Bands Policies Governing the...

  11. Road Nail: Experimental Solar Powered Intelligent Road Marking System

    NASA Astrophysics Data System (ADS)

    Samardžija, Dragan; Teslić, Nikola; Todorović, Branislav M.; Kovač, Erne; Isailović, Đorđe; Miladinović, Bojan

    2012-03-01

    Driving in low visibility conditions (night time, fog or heavy precipitation) is particularly challenging task with an increased probability of traffic accidents and possible injuries. Road Nail is a solar powered intelligent road marking system of wirelessly networked signaling devices that improve driver safety in low visibility conditions along hazardous roadways. Nails or signaling devices are autonomous nodes with capability to accumulate energy, exchange wireless messages, detect approaching vehicles and emit signalization light. We have built an experimental test-bed that consists of 20 nodes and a cellular gateway. Implementation details of the above system, including extensive measurements and performance evaluations in realistic field deployments are presented. A novel distributed network topology discovery scheme is proposed which integrates both sensor and wireless communication aspects, where nodes act autonomously. Finally, integration of the Road Nail system with the cellular network and the Internet is described.

  12. Weight and structural analysis of four structural concepts for a land mobile satellite system

    NASA Technical Reports Server (NTRS)

    Ferebee, M. J.; Wright, R. L.; Farmer, J. T.

    1982-01-01

    The present study is concerned with a Land Mobile Satellite System (LMSS) which can provide mobile communications for commercial and government applications in nonmetropolitan areas of the continental U.S. and Canada as an augmentation to existing and planned terrestrial systems. The satellite system would provide 'narrow band' telecommunications services, thin-route fixed telephone and data services in the 806-890 MHz band, and continuous emergency beacon monitoring in the 406-406.1 MHz band. It is pointed out that a satellite system operating in concert with terrestrial cellular systems could provide truly ubiquitous mobile communications services in the U.S. and Canada. A single shuttle shuttle launch could place the LMSS spacecraft in geosynchronous orbit over the continental U.S. in 1995 with a 10-year lifetime. Attention is given to the structural concepts, a weight analysis, and a structural analysis.

  13. The NavTrax fleet management system

    NASA Astrophysics Data System (ADS)

    McLellan, James F.; Krakiwsky, Edward J.; Schleppe, John B.; Knapp, Paul L.

    The NavTrax System, a dispatch-type automatic vehicle location and navigation system, is discussed. Attention is given to its positioning, communication, digital mapping, and dispatch center components. The positioning module is a robust GPS (Global Positioning System)-based system integrated with dead reckoning devices by a decentralized-federated filter, making the module fault tolerant. The error behavior and characteristics of GPS, rate gyro, compass, and odometer sensors are discussed. The communications module, as presently configured, utilizes UHF radio technology, and plans are being made to employ a digital cellular telephone system. Polling and automatic smart vehicle reporting are also discussed. The digital mapping component is an intelligent digital single line road network database stored in vector form with full connectivity and address ranges. A limited form of map matching is performed for the purposes of positioning, but its main purpose is to define location once position is determined.

  14. Smart repeater system for communications interoperability during multiagency law enforcement operations

    NASA Astrophysics Data System (ADS)

    Crutcher, Richard I.; Jones, R. W.; Moore, Michael R.; Smith, S. F.; Tolley, Alan L.; Rochelle, Robert W.

    1997-02-01

    A prototype 'smart' repeater that provides interoperability capabilities for radio communication systems in multi-agency and multi-user scenarios is being developed by the Oak Ridge National Laboratory. The smart repeater functions as a deployable communications platform that can be dynamically reconfigured to cross-link the radios of participating federal, state, and local government agencies. This interconnection capability improves the coordination and execution of multi-agency operations, including coordinated law enforcement activities and general emergency or disaster response scenarios. The repeater provides multiple channels of operation in the 30-50, 118-136, 138-174, and 403-512 MHz land mobile communications and aircraft bands while providing the ability to cross-connect among multiple frequencies, bands, modulation types, and encryption formats. Additionally, two telephone interconnects provide links to the fixed and cellular telephone networks. The 800- and 900-MHz bands are not supported by the prototype, but the modular design of the system accommodates future retrofits to extend frequency capabilities with minimal impact to the system. Configuration of the repeater is through a portable personal computer with a Windows-based graphical interface control screen that provides dynamic reconfiguration of network interconnections and formats.

  15. Design of biomimetic cellular scaffolds for co-culture system and their application

    PubMed Central

    Kook, Yun-Min; Jeong, Yoon; Lee, Kangwon; Koh, Won-Gun

    2017-01-01

    The extracellular matrix of most natural tissues comprises various types of cells, including fibroblasts, stem cells, and endothelial cells, which communicate with each other directly or indirectly to regulate matrix production and cell functionality. To engineer multicellular interactions in vitro, co-culture systems have achieved tremendous success achieving a more realistic microenvironment of in vivo metabolism than monoculture system in the past several decades. Recently, the fields of tissue engineering and regenerative medicine have primarily focused on three-dimensional co-culture systems using cellular scaffolds, because of their physical and biological relevance to the extracellular matrix of actual tissues. This review discusses several materials and methods to create co-culture systems, including hydrogels, electrospun fibers, microfluidic devices, and patterning for biomimetic co-culture system and their applications for specific tissue regeneration. Consequently, we believe that culture systems with appropriate physical and biochemical properties should be developed, and direct or indirect cell–cell interactions in the remodeled tissue must be considered to obtain an optimal tissue-specific microenvironment. PMID:29081966

  16. Design of biomimetic cellular scaffolds for co-culture system and their application.

    PubMed

    Kook, Yun-Min; Jeong, Yoon; Lee, Kangwon; Koh, Won-Gun

    2017-01-01

    The extracellular matrix of most natural tissues comprises various types of cells, including fibroblasts, stem cells, and endothelial cells, which communicate with each other directly or indirectly to regulate matrix production and cell functionality. To engineer multicellular interactions in vitro, co-culture systems have achieved tremendous success achieving a more realistic microenvironment of in vivo metabolism than monoculture system in the past several decades. Recently, the fields of tissue engineering and regenerative medicine have primarily focused on three-dimensional co-culture systems using cellular scaffolds, because of their physical and biological relevance to the extracellular matrix of actual tissues. This review discusses several materials and methods to create co-culture systems, including hydrogels, electrospun fibers, microfluidic devices, and patterning for biomimetic co-culture system and their applications for specific tissue regeneration. Consequently, we believe that culture systems with appropriate physical and biochemical properties should be developed, and direct or indirect cell-cell interactions in the remodeled tissue must be considered to obtain an optimal tissue-specific microenvironment.

  17. Spacecraft design project: Low Earth orbit communications satellite

    NASA Technical Reports Server (NTRS)

    Moroney, Dave; Lashbrook, Dave; Mckibben, Barry; Gardener, Nigel; Rivers, Thane; Nottingham, Greg; Golden, Bill; Barfield, Bill; Bruening, Joe; Wood, Dave

    1991-01-01

    This is the final product of the spacecraft design project completed to fulfill the academic requirements of the Spacecraft Design and Integration 2 course (AE-4871) taught at the U.S. Naval Postgraduate School. The Spacecraft Design and Integration 2 course is intended to provide students detailed design experience in selection and design of both satellite system and subsystem components, and their location and integration into a final spacecraft configuration. The design team pursued a design to support a Low Earth Orbiting (LEO) communications system (GLOBALSTAR) currently under development by the Loral Cellular Systems Corporation. Each of the 14 team members was assigned both primary and secondary duties in program management or system design. Hardware selection, spacecraft component design, analysis, and integration were accomplished within the constraints imposed by the 11 week academic schedule and the available design facilities.

  18. The brain as a system of nested but partially overlapping networks. Heuristic relevance of the model for brain physiology and pathology.

    PubMed

    Agnati, L F; Guidolin, D; Fuxe, K

    2007-01-01

    A new model of the brain organization is proposed. The model is based on the assumption that a global molecular network enmeshes the entire central nervous system. Thus, brain extra-cellular and intra-cellular molecular networks are proposed to communicate at the level of special plasma membrane regions (e.g., the lipid rafts) where horizontal molecular networks can represent input/output regions allowing the cell to have informational exchanges with the extracellular environment. Furthermore, some "pervasive signals" such as field potentials, pressure waves and thermal gradients that affect large parts of the brain cellular and molecular networks are discussed. Finally, at least two learning paradigms are analyzed taking into account the possible role of Volume Transmission: the so-called model of "temporal difference learning" and the "Turing B-unorganised machine". The relevance of this new view of brain organization for a deeper understanding of some neurophysiological and neuropathological aspects of its function is briefly discussed.

  19. Cellular telephone interference with medical equipment.

    PubMed

    Tri, Jeffrey L; Severson, Rodney P; Firl, Allen R; Hayes, David L; Abenstein, John P

    2005-10-01

    To assess the potential electromagnetic interference (EMI) effects that new or current-generation cellular telephones have on medical devices. For this study, performed at the Mayo Clinic in Rochester, Minn, between March 9, 2004, and April 24, 2004, we tested 16 different medical devices with 6 cellular telephones to assess the potential for EMI. Two of the medical devices were tested with both new and old interface modules. The 6 cellular telephones chosen represent the different cellular technology protocols in use: Code Division Multiple Access (2 models), Global System for Mobile communications, Integrated Digital Enhanced Network, Time Division Multiple Access, and analog. The cellular telephones were tested when operating at or near their maximum power output. The medical devices, connected to clinical simulators during testing, were monitored by observing the device displays and alarms. Of 510 tests performed, the incidence of clinically important interference was 1.2%; EMI was Induced in 108 tests (21.2%). Interference occurred in 7 (44%) of the 16 devices tested. Cellular telephones can interfere with medical equipment. Technology changes in both cellular telephones and medical equipment may continue to mitigate or may worsen clinically relevant interference. Compared with cellular telephones tested in previous studies, those currently in use must be closer to medical devices before any interference is noticed. However, periodic testing of cellular telephones to determine their effects on medical equipment will be required.

  20. 47 CFR 22.929 - Application requirements for the Cellular Radiotelephone Service.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Application requirements for the Cellular Radiotelephone Service. 22.929 Section 22.929 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.929 Application...

  1. 47 CFR 22.929 - Application requirements for the Cellular Radiotelephone Service.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Application requirements for the Cellular Radiotelephone Service. 22.929 Section 22.929 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.929 Application...

  2. 47 CFR 22.929 - Application requirements for the Cellular Radiotelephone Service.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Application requirements for the Cellular Radiotelephone Service. 22.929 Section 22.929 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.929 Application...

  3. Intercellular and systemic spread of RNA and RNAi in plants.

    PubMed

    Nazim Uddin, Mohammad; Kim, Jae-Yean

    2013-01-01

    Plants possess dynamic networks of intercellular communication that are crucial for plant development and physiology. In plants, intercellular communication involves a combination of ligand-receptor-based apoplasmic signaling, and plasmodesmata and phloem-mediated symplasmic signaling. The intercellular trafficking of macromolecules, including RNAs and proteins, has emerged as a novel mechanism of intercellular communication in plants. Various forms of regulatory RNAs move over distinct cellular boundaries through plasmodesmata and phloem. This plant-specific, non-cell-autonomous RNA trafficking network is also involved in development, nutrient homeostasis, gene silencing, pathogen defense, and many other physiological processes. However, the mechanism underlying macromolecular trafficking in plants remains poorly understood. Current progress made in RNA trafficking research and its biological relevance to plant development will be summarized. Diverse plant regulatory mechanisms of cell-to-cell and systemic long-distance transport of RNAs, including mRNAs, viral RNAs, and small RNAs, will also be discussed. Copyright © 2013 John Wiley & Sons, Ltd.

  4. MiniAERCam Ranging

    NASA Technical Reports Server (NTRS)

    Talley, Tom

    2003-01-01

    Johnson Space Center (JSC) is designing a small, remotely controlled vehicle that will carry two color and one black and white video cameras in space. The device will launch and retrieve from the Space Vehicle and be used for remote viewing. Off the shelf cellular technology is being used as the basis for communication system design. Existing plans include using multiple antennas to make simultaneous estimates of the azimuth of the MiniAERCam from several sites on the Space Station and use triangulation to find the location of the device. Adding range detection capability to each of the nodes on the Space Vehicle would allow an estimate of the location of the MiniAERCam to be made at each Communication And Telemetry Box (CATBox) independent of all the other communication nodes. This project will investigate the techniques used by the Global Positioning System (GPS) to achieve accurate positioning information and adapt those strategies that are appropriate to the design of the CATBox range determination system.

  5. 47 CFR 22.925 - Prohibition on airborne operation of cellular telephones.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Prohibition on airborne operation of cellular telephones. 22.925 Section 22.925 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.925 Prohibition on airborne...

  6. 47 CFR 22.925 - Prohibition on airborne operation of cellular telephones.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Prohibition on airborne operation of cellular telephones. 22.925 Section 22.925 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.925 Prohibition on airborne...

  7. [Risk-oriented model of the control of the level of electric magnetic fields of base stations of cellular communications].

    PubMed

    Lutsenko, L A; Tulakin, A V; Egorova, A M; Mikhailova, O M; Gvozdeva, L L; Chigryay, E K

    The purpose of this study was to give the description of harmful effects of the impact of electromagnetic radiations from base stations of cellular communication as the most common sources of radio frequencies of electromagnetic fields in the environment. The highest values of the energy flux density were measured on the roofs of houses where antennas are installed - more than 10 pW/cm. The lowest values were recorded in inside premises with expositions of 0.1-1 pW/cm. In the close location of the railway station to the base stations of the cellular communication there was seen a cumulative effect. There are proposed both new safe hygienic approaches to the control for the safety of the work of base station and protective measures.

  8. Light fidelity (Li-Fi): towards all-optical networking

    NASA Astrophysics Data System (ADS)

    Tsonev, Dobroslav; Videv, Stefan; Haas, Harald

    2013-12-01

    Motivated by the looming radio frequency (RF) spectrum crisis, this paper aims at demonstrating that optical wireless communication (OWC) has now reached a state where it can demonstrate that it is a viable and matured solution to this fundamental problem. In particular, for indoor communications where most mobile data traffic is consumed, light fidelity (Li-Fi) which is related to visible light communication (VLC) offers many key advantages, and effective solutions to the issues that have been posed in the last decade. This paper discusses all key component technologies required to realize optical cellular communication systems referred to here as optical attocell networks. Optical attocells are the next step in the progression towards ever smaller cells, a progression which is known to be the most significant contributor to the improvements in network spectral efficiencies in RF wireless networks.

  9. Multicellular regulation of entropy, spatial order, and information

    NASA Astrophysics Data System (ADS)

    Youk, Hyun

    Many multicellular systems such as tissues and microbial biofilms consist of cells that secrete and sense signalling molecules. Understanding how collective behaviours of secrete-and-sense cells is an important challenge. We combined experimental and theoretical approaches to understand multicellular coordination of gene expression and spatial pattern formation among secrete-and-sense cells. We engineered secrete-and-sense yeast cells to show that cells can collectively and permanently remember a past event by reminding each other with their secreted signalling molecule. If one cell ``forgets'' then another cell can remind it. Cell-cell communication ensures a long-term (permanent) memory by overcoming common limitations of intracellular memory. We also established a new theoretical framework inspired by statistical mechanics to understand how fields of secrete-and-sense cells form spatial patterns. We introduce new metrics - cellular entropy, cellular Hamiltonian, and spatial order index - for dynamics of cellular automata that form spatial patterns. Our theory predicts how fast any spatial patterns form, how ordered they are, and establishes cellular Hamiltonian that, like energy for non-living systems, monotonically decreases towards a minimum over time. ERC Starting Grant (MultiCellSysBio), NWO VIDI, NWO NanoFront.

  10. SSC San Diego Biennial Review 2003. Vol 2: Communication and Information Systems

    DTIC Science & Technology

    2003-01-01

    University, Department of Electrical and Computer Engineering) Michael Jablecki (Science and Technology Corporation) Stochastic Unified Multiple...wearable computers and cellular phones. The technology-transfer process involved a coalition of government and industrial partners, each providing...the design and fabrication of the coupler. SSC San Diego developed a computer -controlled fused fiber fabrication station to achieve the required

  11. A cognitive mobile BTS solution with software-defined radioelectric sensing.

    PubMed

    Muñoz, Jorge; Alonso, Javier Vales; García, Francisco Quiñoy; Costas, Sergio; Pillado, Marcos; Castaño, Francisco Javier González; Sánchez, Manuel García; Valcarce, Roberto López; Bravo, Cristina López

    2013-02-05

    Private communications inside large vehicles such as ships may be effectively provided using standard cellular systems. In this paper we propose a new solution based on software-defined radio with electromagnetic sensing support. Software-defined radio allows low-cost developments and, potentially, added-value services not available in commercial cellular networks. The platform of reference, OpenBTS, only supports single-channel cells. Our proposal, however, has the ability of changing BTS channel frequency without disrupting ongoing communications. This ability should be mandatory in vehicular environments, where neighbouring cell configurations may change rapidly, so a moving cell must be reconfigured in real-time to avoid interferences. Full details about frequency occupancy sensing and the channel reselection procedure are provided in this paper. Moreover, a procedure for fast terminal detection is proposed. This may be decisive in emergency situations, e.g., if someone falls overboard. Different tests confirm the feasibility of our proposal and its compatibility with commercial GSM terminals.

  12. A Cognitive Mobile BTS Solution with Software-Defined Radioelectric Sensing

    PubMed Central

    Muñoz, Jorge; Alonso, Javier Vales; García, Francisco Quiñoy; Costas, Secundino; Pillado, Marcos; Castaño, Francisco Javier González; Sánchez, Manuel Garćia; Valcarce, Roberto López; Bravo, Cristina López

    2013-01-01

    Private communications inside large vehicles such as ships may be effectively provided using standard cellular systems. In this paper we propose a new solution based on software-defined radio with electromagnetic sensing support. Software-defined radio allows low-cost developments and, potentially, added-value services not available in commercial cellular networks. The platform of reference, OpenBTS, only supports single-channel cells. Our proposal, however, has the ability of changing BTS channel frequency without disrupting ongoing communications. This ability should be mandatory in vehicular environments, where neighbouring cell configurations may change rapidly, so a moving cell must be reconfigured in real-time to avoid interferences. Full details about frequency occupancy sensing and the channel reselection procedure are provided in this paper. Moreover, a procedure for fast terminal detection is proposed. This may be decisive in emergency situations, e.g., if someone falls overboard. Different tests confirm the feasibility of our proposal and its compatibility with commercial GSM terminals. PMID:23385417

  13. Image processing for navigation on a mobile embedded platform

    NASA Astrophysics Data System (ADS)

    Preuss, Thomas; Gentsch, Lars; Rambow, Mark

    2006-02-01

    Mobile computing devices such as PDAs or cellular phones may act as "Personal Multimedia Exchanges", but they are limited in their processing power as well as in their connectivity. Sensors as well as cellular phones and PDAs are able to gather multimedia data, e. g. images, but leak computing power to process that data on their own. Therefore, it is necessary, that these devices connect to devices with more performance, which provide e.g. image processing services. In this paper, a generic approach is presented that connects different kinds of clients with each other and allows them to interact with more powerful devices. This architecture, called BOSPORUS, represents a communication framework for dynamic peer-to-peer computing. Each peer offers and uses services in this network and communicates loosely coupled and asynchronously with the others. These features make BOSPORUS a service oriented network architecture (SONA). A mobile embedded system, which uses external services for image processing based on the BOSPORUS Framework is shown as an application of the BOSPORUS framework.

  14. 47 CFR 22.939 - Site availability requirements for applications competing with cellular renewal applications.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Site availability requirements for applications competing with cellular renewal applications. 22.939 Section 22.939 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22...

  15. 47 CFR 22.939 - Site availability requirements for applications competing with cellular renewal applications.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Site availability requirements for applications competing with cellular renewal applications. 22.939 Section 22.939 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22...

  16. Requirements for a mobile communications satellite system. Volume 1: Executive summary

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Three types of satellite-aided mobile communications are considered for users in areas not served by (terrestrial) cellular radio systems. In System 1, mobile units are provided a direct satellite link to a gateway station, which serves as the interface to the terrestrial toll network. In System 2, a terrestrial radio link similar to those in cellular systems connects the mobile unit to a translator station; each translator relays the traffic from mobile units in its vicinity, via satellite, to the regional gateway. It is not feasible for System 2 to provide ubiquitous coverage. Therefore, System 3 is introduced, in which the small percentage of users not within range of a translator are provided a direct satellite link as in System 1. While System 2 can operate with leased satellite capacity, Systems 1 and 3 require a dedicated satellite. A major portion of this study is concerned with the design of a satellite for System 1. A weight limit of 10,000 lbs, corresponding to the projected 1990 STS capability, is imposed on the design. Frequency re-use of the allocated spectrum, through multiple satellite beams, is employed to generate the specified system capacity. Both offset-fed and center-fed reflectors are considered. For an assumed 10-MHz allocation and a population of 350,000 subscribers, a two-satellite system is required. The reflector diameters corresponding to offset-fed and center-fed geometries are 46 m and 62 m, respectively. Thus, large-space-structure technology is inherent to the implementation of System 1. In addition to establishing the technical requirements for the three types of satellite systems, the monthly service charge needed to provide a specified return on invested capital is computed. A net present value analysis is used for this purpose.

  17. Future prospects of health management systems using cellular phones.

    PubMed

    Kim, Hun-Sung; Hwang, Yunji; Lee, Jae-Ho; Oh, Hye Young; Kim, Yi-Jun; Kwon, Hyeon Yoon; Kang, Hyoseung; Kim, Hyunah; Park, Rae Woong; Kim, Ju Han

    2014-06-01

    Cellular phones enable communication between healthcare providers and patients for prevention, diagnosis, and treatment of diseases. However, few studies have examined the user-friendliness or effectiveness of cellular phone-based medical informatics (CPBMI) for healthcare. This study investigated the use of CPBMI to identify its current status within the medical field, advantages and disadvantages, practicability, clinical effectiveness, costs, and cost-saving potential. CPBMI was validated in terms of practicality and provision of medical benefits. It is critical to use CPBMI in accordance with the different features of each disease and condition. Use of CPBMI is expected to be especially useful for patients with chronic disease. We discussed the current status of the clinical use, benefits, and risks of CPBMI. CPBMI and information technology-based health management tools are anticipated to become useful and effective components of healthcare management in the future.

  18. The Iridium (tm) system: Personal communications anytime, anyplace

    NASA Technical Reports Server (NTRS)

    Hatlelid, John E.; Casey, Larry

    1993-01-01

    The Iridium system is designed to provide handheld personal communications between diverse locations around the world at any time and without prior knowledge of the location of the personal units. This paper provides an overview of the system, the services it provides, its operation, and an overview of the commercial practices and relatively high volume satellite production techniques which will make the system cost effective. A constellation of 66 satellites will provide an orbiting, spherical-shell, infrastructure for this global calling capability. The satellites act as tall cellular towers and allow convenient operation for portable handheld telephones. The system will provide a full range of services including voice, paging, data, geolocation, and fax capabilities. Motorola is a world leader in the production of high volume, high quality, reliable telecommunications hardware. One of Iridium's goals is to apply these production techniques to high reliability space hardware. Concurrent engineering, high performance work teams, advanced manufacturing technologies, and improved assembly and test methods are some of the techniques that will keep the Iridium system cost effective. Mobile, global, flexible personal communications are coming that will allow anyone to call or receive a call from/to anyplace at anytime. The Iridium system will provide communications where none exist today. This connectivity will allow increased information transfer, open new markets for various business endeavors, and in general increase productivity and development.

  19. The Iridium (tm) system: Personal communications anytime, anyplace

    NASA Astrophysics Data System (ADS)

    Hatlelid, John E.; Casey, Larry

    The Iridium system is designed to provide handheld personal communications between diverse locations around the world at any time and without prior knowledge of the location of the personal units. This paper provides an overview of the system, the services it provides, its operation, and an overview of the commercial practices and relatively high volume satellite production techniques which will make the system cost effective. A constellation of 66 satellites will provide an orbiting, spherical-shell, infrastructure for this global calling capability. The satellites act as tall cellular towers and allow convenient operation for portable handheld telephones. The system will provide a full range of services including voice, paging, data, geolocation, and fax capabilities. Motorola is a world leader in the production of high volume, high quality, reliable telecommunications hardware. One of Iridium's goals is to apply these production techniques to high reliability space hardware. Concurrent engineering, high performance work teams, advanced manufacturing technologies, and improved assembly and test methods are some of the techniques that will keep the Iridium system cost effective. Mobile, global, flexible personal communications are coming that will allow anyone to call or receive a call from/to anyplace at anytime. The Iridium system will provide communications where none exist today. This connectivity will allow increased information transfer, open new markets for various business endeavors, and in general increase productivity and development.

  20. The use of technology for urgent clinician to clinician communications: a systematic review of the literature.

    PubMed

    Nguyen, Cristina; McElroy, Lisa M; Abecassis, Michael M; Holl, Jane L; Ladner, Daniela P

    2015-02-01

    Urgent clinician-clinician communications require routes of contact that are fast and dependable, and allow for the exchange of complex information. Despite the increasing focus on improving healthcare delivery systems over the past decade, few studies have examined the role of technology in clinician-clinician communication. The aim of this study was to review the literature examining the role of devices and technology in facilitating urgent clinician-clinician communication to identify critical areas for future research. A search of Pub Med was performed using the terms (((("Critical Care"[Mesh] OR "urgent")))) AND (((hospital communication systems[MeSH Terms]) OR health communication[MeSH Terms]) OR interdisciplinary communication[MeSH Terms]). Commentaries and editorials were excluded. The initial search returned 272 articles, which were reviewed to identify articles describing: (1) the role of technological support or devices in clinician-clinician communication, (2) technology-based interventions that improved clinician-to-clinician communication in hospitals or acute care facilities related to critically ill patients, or (3) critical information exchange. A total of 16 articles were included in the final review. These were grouped into three categories: alphanumeric pagers, cellular and smart telephones, and novel uses of technology. Breakdowns in clinician-clinician communication are complex and cannot be solved through the implementation of devices or technologically advanced systems alone. It is essential to understand the correlation between emerging technologies, a demanding workload, and clinician-clinician interaction. Enhanced communication of clinical ideas, opportunities for team discussion, and a sense of partnership and support require not just increased information, but enhanced delivery. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  1. Exosomes and their role in the micro-/macro-environment: a comprehensive review

    PubMed Central

    Javeed, Naureen; Mukhopadhyay, Debabrata

    2017-01-01

    The importance of extracellular vesicles (EVs) in cell-cell communication has long been recognized due to their ability to transfer important cellular cargoes such as DNA, mRNA, miRNAs, and proteins to target cells. Compelling evidence supports the role of EVs in the horizontal transfer of cellular material which has the potential to influence normal cellular physiology and promote various disease states. Of the different types of EVs, exosomes have garnered much attention in the past decade due to their abundance in various biological fluids and ability to affect multiple organ systems. The main focus of this review will be on cancer and how cancer-derived exosomes are important mediators of metastasis, angiogenesis, immune modulation, and the tumor macro-/microenvironment. We will also discuss exosomes as potential biomarkers for cancers due to their abundance in biological fluids, ease of uptake, and cellular content. Exosome use in diagnosis, prognosis, and in establishing treatment regimens has enormous potential to revolutionize patient care. PMID:28290182

  2. Exosomes and their role in the micro-/macro-environment: a comprehensive review.

    PubMed

    Javeed, Naureen; Mukhopadhyay, Debabrata

    2017-09-26

    The importance of extracellular vesicles (EVs) in cell-cell communication has long been recognized due to their ability to transfer important cellular cargoes such as DNA, mRNA, miRNAs, and proteins to target cells. Compelling evidence supports the role of EVs in the horizontal transfer of cellular material which has the potential to influence normal cellular physiology and promote various disease states. Of the different types of EVs, exosomes have garnered much attention in the past decade due to their abundance in various biological fluids and ability to affect multiple organ systems. The main focus of this review will be on cancer and how cancer-derived exosomes are important mediators of metastasis, angiogenesis, immune modulation, and the tumor macro-/microenvironment. We will also discuss exosomes as potential biomarkers for cancers due to their abundance in biological fluids, ease of uptake, and cellular content. Exosome use in diagnosis, prognosis, and in establishing treatment regimens has enormous potential to revolutionize patient care.

  3. GPS and GPRS Based Telemonitoring System for Emergency Patient Transportation

    PubMed Central

    Satyanarayana, K.; Sarma, A. D.; Sravan, J.; Malini, M.; Venkateswarlu, G.

    2013-01-01

    Telemonitoring during the golden hour of patient transportation helps to improve medical care. Presently there are different physiological data acquisition and transmission systems using cellular network and radio communication links. Location monitoring systems and video transmission systems are also commercially available. The emergency patient transportation systems uniquely require transmission of data pertaining to the patient, vehicle, time of the call, physiological signals (like ECG, blood pressure, a body temperature, and blood oxygen saturation), location information, a snap shot of the patient, and voice. These requirements are presently met by using separate communication systems for voice, physiological data, and location that result in a lot of inconvenience to the technicians, maintenance related issues, in addition to being expensive. This paper presents design, development, and implementation of such a telemonitoring system for emergency patient transportation employing ARM 9 processor module. This system is found to be very useful for the emergency patient transportation being undertaken by organizations like the Emergency Management Research Institute (EMRI). PMID:27019844

  4. A Wireless Communications Laboratory on Cellular Network Planning

    ERIC Educational Resources Information Center

    Dawy, Z.; Husseini, A.; Yaacoub, E.; Al-Kanj, L.

    2010-01-01

    The field of radio network planning and optimization (RNPO) is central for wireless cellular network design, deployment, and enhancement. Wireless cellular operators invest huge sums of capital on deploying, launching, and maintaining their networks in order to ensure competitive performance and high user satisfaction. This work presents a lab…

  5. Arenani: pointing and information query system for object beyond your reach

    NASA Astrophysics Data System (ADS)

    Adachi, Mariko; Sakamoto, Kunio

    2008-03-01

    The authors developed a prototype information query system. It is easy to get the information about an object with in your reach. But it is troublesome to do the same in case that the object is far away. If someone is around you, you can ask an easy question with a finger pointing; "What is that?" Our developed system also realizes this approach using information technologies. The system consists of a laser pointer, transmitter and receiver units for an optical communication. The laser pointer is used for pointing an object. Moreover this laser light is modulated for sending information about user's identification (ID) codes to identify who asks a question. Each object has a receiver for laser light communication and sends user's identification to a main computer. After pointing an object, a questioner receives an answer through a wireless information network like an email on the cellular phone.

  6. Cellular-V2X Communications for Platooning: Design and Evaluation

    PubMed Central

    2018-01-01

    Platooning is a cooperative driving application where autonomous/semi-autonomous vehicles move on the same lane in a train-like manner, keeping a small constant inter-vehicle distance, in order to reduce fuel consumption and gas emissions and to achieve safe and efficient transport. To this aim, they may exploit multiple on-board sensors (e.g., radars, LiDARs, positioning systems) and direct vehicle-to-vehicle communications to synchronize their manoeuvres. The main objective of this paper is to discuss the design choices and factors that determine the performance of a platooning application, when exploiting the emerging cellular vehicle-to-everything (C-V2X) communication technology and considering the scheduled mode, specified by 3GPP for communications over the sidelink assisted by the eNodeB. Since no resource management algorithm is currently mandated by 3GPP for this new challenging context, we focus on analyzing the feasibility and performance of the dynamic scheduling approach, with platoon members asking for radio resources on a per-packet basis. We consider two ways of implementing dynamic scheduling, currently unspecified by 3GPP: the sequential mode, that is somehow reminiscent of time division multiple access solutions based on IEEE 802.11p—till now the only investigated access technology for platooning—and the simultaneous mode with spatial frequency reuse enabled by the eNodeB. The evaluation conducted through system-level simulations provides helpful insights about the proposed configurations and C-V2X parameter settings that mainly affect the reliability and latency performance of data exchange in platoons, under different load settings. Achieved results show that the proposed simultaneous mode succeeds in reducing the latency in the update cycle in each vehicle’s controller, thus enabling future high-density platooning scenarios. PMID:29751690

  7. Cellular-V2X Communications for Platooning: Design and Evaluation.

    PubMed

    Nardini, Giovanni; Virdis, Antonio; Campolo, Claudia; Molinaro, Antonella; Stea, Giovanni

    2018-05-11

    Platooning is a cooperative driving application where autonomous/semi-autonomous vehicles move on the same lane in a train-like manner, keeping a small constant inter-vehicle distance, in order to reduce fuel consumption and gas emissions and to achieve safe and efficient transport. To this aim, they may exploit multiple on-board sensors (e.g., radars, LiDARs, positioning systems) and direct vehicle-to-vehicle communications to synchronize their manoeuvres. The main objective of this paper is to discuss the design choices and factors that determine the performance of a platooning application, when exploiting the emerging cellular vehicle-to-everything (C-V2X) communication technology and considering the scheduled mode, specified by 3GPP for communications over the sidelink assisted by the eNodeB. Since no resource management algorithm is currently mandated by 3GPP for this new challenging context, we focus on analyzing the feasibility and performance of the dynamic scheduling approach, with platoon members asking for radio resources on a per-packet basis. We consider two ways of implementing dynamic scheduling, currently unspecified by 3GPP: the sequential mode, that is somehow reminiscent of time division multiple access solutions based on IEEE 802.11p-till now the only investigated access technology for platooning-and the simultaneous mode with spatial frequency reuse enabled by the eNodeB. The evaluation conducted through system-level simulations provides helpful insights about the proposed configurations and C-V2X parameter settings that mainly affect the reliability and latency performance of data exchange in platoons, under different load settings. Achieved results show that the proposed simultaneous mode succeeds in reducing the latency in the update cycle in each vehicle's controller, thus enabling future high-density platooning scenarios.

  8. Extracellular vesicles and intercellular communication within the nervous system

    PubMed Central

    Fitzpatrick, Zachary; Maguire, Casey A.; Breakefield, Xandra O.

    2016-01-01

    Extracellular vesicles (EVs, including exosomes) are implicated in many aspects of nervous system development and function, including regulation of synaptic communication, synaptic strength, and nerve regeneration. They mediate the transfer of packets of information in the form of nonsecreted proteins and DNA/RNA protected within a membrane compartment. EVs are essential for the packaging and transport of many cell-fate proteins during development as well as many neurotoxic misfolded proteins during pathogenesis. This form of communication provides another dimension of cellular crosstalk, with the ability to assemble a “kit” of directional instructions made up of different molecular entities and address it to specific recipient cells. This multidimensional form of communication has special significance in the nervous system. How EVs help to orchestrate the wiring of the brain while allowing for plasticity associated with learning and memory and contribute to regeneration and degeneration are all under investigation. Because they carry specific disease-related RNAs and proteins, practical applications of EVs include potential uses as biomarkers and therapeutics. This Review describes our current understanding of EVs and serves as a springboard for future advances, which may reveal new important mechanisms by which EVs in coordinate brain and body function and dysfunction. PMID:27035811

  9. Evolution of Microbial Quorum Sensing to Human Global Quorum Sensing: An Insight into How Gap Junctional Intercellular Communication Might Be Linked to the Global Metabolic Disease Crisis.

    PubMed

    Trosko, James E

    2016-06-15

    The first anaerobic organism extracted energy for survival and reproduction from its source of nutrients, with the genetic means to ensure protection of its individual genome but also its species survival. While it had a means to communicate with its community via simple secreted molecules ("quorum sensing"), the eventual shift to an aerobic environment led to multi-cellular metazoan organisms, with evolutionary-selected genes to form extracellular matrices, stem cells, stem cell niches, and a family of gap junction or "connexin" genes. These germinal and somatic stem cells responded to extracellular signals that triggered intra-cellular signaling to regulate specific genes out of the total genome. These extra-cellular induced intra-cellular signals also modulated gap junctional intercellular communication (GJIC) in order to regulate the new cellular functions of symmetrical and asymmetrical cell division, cell differentiation, modes of cell death, and senescence. Within the hierarchical and cybernetic concepts, differentiated by neurons organized in the brain of the Homo sapiens, the conscious mind led to language, abstract ideas, technology, myth-making, scientific reasoning, and moral decision-making, i.e., the creation of culture. Over thousands of years, this has created the current collision between biological and cultural evolution, leading to the global "metabolic disease" crisis.

  10. Maturity Assessment of Knowledge Management at PT. Cellular Tbk.: A Case Study at A Telecommunication Operator in Indonesia

    ERIC Educational Resources Information Center

    Ghazali, Achmad; Vivaldi, Harly; Putranto, Nur Arief Rahmatsyah

    2017-01-01

    Managing knowledge integrally as one of the company's asset is now a necessity to be part of the knowledge-based economy in the global industry. PT Cellular Tbk. (Cellular) has been a player of mobile communication service for more than 20 years. Cellular shows business transformation through increased gross revenue from Data services while…

  11. Exploring the physical layer frontiers of cellular uplink: The Vienna LTE-A Uplink Simulator.

    PubMed

    Zöchmann, Erich; Schwarz, Stefan; Pratschner, Stefan; Nagel, Lukas; Lerch, Martin; Rupp, Markus

    Communication systems in practice are subject to many technical/technological constraints and restrictions. Multiple input, multiple output (MIMO) processing in current wireless communications, as an example, mostly employs codebook-based pre-coding to save computational complexity at the transmitters and receivers. In such cases, closed form expressions for capacity or bit-error probability are often unattainable; effects of realistic signal processing algorithms on the performance of practical communication systems rather have to be studied in simulation environments. The Vienna LTE-A Uplink Simulator is a 3GPP LTE-A standard compliant MATLAB-based link level simulator that is publicly available under an academic use license, facilitating reproducible evaluations of signal processing algorithms and transceiver designs in wireless communications. This paper reviews research results that have been obtained by means of the Vienna LTE-A Uplink Simulator, highlights the effects of single-carrier frequency-division multiplexing (as the distinguishing feature to LTE-A downlink), extends known link adaptation concepts to uplink transmission, shows the implications of the uplink pilot pattern for gathering channel state information at the receiver and completes with possible future research directions.

  12. Cellular communication and “non-targeted effects”: Modelling approaches

    NASA Astrophysics Data System (ADS)

    Ballarini, Francesca; Facoetti, Angelica; Mariotti, Luca; Nano, Rosanna; Ottolenghi, Andrea

    2009-10-01

    During the last decade, a large number of experimental studies on the so-called "non-targeted effects", in particular bystander effects, outlined that cellular communication plays a significant role in the pathways leading to radiobiological damage. Although it is known that two main types of cellular communication (i.e. via gap junctions and/or molecular messengers diffusing in the extra-cellular environment, such as cytokines, NO etc.) play a major role, it is of utmost importance to better understand the underlying mechanisms, and how such mechanisms can be modulated by ionizing radiation. Though the "final" goal is of course to elucidate the in vivo scenario, in the meanwhile also in vitro studies can provide useful insights. In the present paper we will discuss key issues on the mechanisms underlying non-targeted effects and cell communication, for which theoretical models and simulation codes can be of great help. In this framework, we will present in detail three literature models, as well as an approach under development at the University of Pavia. More specifically, we will first focus on a version of the "State-Vector Model" including bystander-induced apoptosis of initiated cells, which was successfully fitted to in vitro data on neoplastic transformation supporting the hypothesis of a protective bystander effect mediated by apoptosis. The second analyzed model, focusing on the kinetics of bystander effects in 3D tissues, was successfully fitted to data on bystander damage in an artificial 3D skin system, indicating a signal range of the order of 0.7-1 mm. A third model for bystander effect, taking into account of spatial location, cell killing and repopulation, showed dose-response curves increasing approximately linearly at low dose rates but quickly flattening out for higher dose rates, also predicting an effect augmentation following dose fractionation. Concerning the Pavia approach, which can model the release, diffusion and depletion/degradation of candidate signals (e.g. cytokines) travelling in the extra-cellular environment, the good agreement with ad hoc experimental data obtained in our laboratory validated the adopted approach, which in the future can be applied also to other candidate signals. Although the available information is still not sufficient to decide whether the Linear No Threshold approach for low dose risk - including space radiation risk - has to be modified, these studies confirmed the need of a paradigm shift in (low-dose) radiobiology, where the DNA-centric vision needs to be integrated by a wider vision where cells constitute an organized population responding to external stimuli in a collective fashion, communicating by means of different molecular signals. Further studies, in particular in vivo (or at least in 3D tissues) and possibly combined with human epidemiological data, will be crucial to help solving such questions in the future.

  13. Biochar and microbial signaling: production conditions determine effects on microbial communication.

    PubMed

    Masiello, Caroline A; Chen, Ye; Gao, Xiaodong; Liu, Shirley; Cheng, Hsiao-Ying; Bennett, Matthew R; Rudgers, Jennifer A; Wagner, Daniel S; Zygourakis, Kyriacos; Silberg, Jonathan J

    2013-10-15

    Charcoal has a long soil residence time, which has resulted in its production and use as a carbon sequestration technique (biochar). A range of biological effects can be triggered by soil biochar that can positively and negatively influence carbon storage, such as changing the decomposition rate of organic matter and altering plant biomass production. Sorption of cellular signals has been hypothesized to underlie some of these effects, but it remains unknown whether the binding of biochemical signals occurs, and if so, on time scales relevant to microbial growth and communication. We examined biochar sorption of N-3-oxo-dodecanoyl-L-homoserine lactone, an acyl-homoserine lactone (AHL) intercellular signaling molecule used by many gram-negative soil microbes to regulate gene expression. We show that wood biochars disrupt communication within a growing multicellular system that is made up of sender cells that synthesize AHL and receiver cells that express green fluorescent protein in response to an AHL signal. However, biochar inhibition of AHL-mediated cell-cell communication varied, with the biochar prepared at 700 °C (surface area of 301 m(2)/g) inhibiting cellular communication 10-fold more than an equivalent mass of biochar prepared at 300 °C (surface area of 3 m(2)/g). These findings provide the first direct evidence that biochars elicit a range of effects on gene expression dependent on intercellular signaling, implicating the method of biochar preparation as a parameter that could be tuned to regulate microbial-dependent soil processes, like nitrogen fixation and pest attack of root crops.

  14. Biochar and microbial signaling: production conditions determine effects on microbial communication

    PubMed Central

    Masiello, Caroline A.; Chen, Ye; Gao, Xiaodong; Liu, Shirley; Cheng, Hsiao-Ying; Bennett, Matthew R.; Rudgers, Jennifer A.; Wagner, Daniel S.; Zygourakis, Kyriacos; Silberg, Jonathan J.

    2013-01-01

    Charcoal has a long soil residence time, which has resulted in its production and use as a carbon sequestration technique (biochar). A range of biological effects can be triggered by soil biochar that can positively and negatively influence carbon storage, such as changing the decomposition rate of organic matter and altering plant biomass production. Sorption of cellular signals has been hypothesized to underlie some of these effects, but it remains unknown whether the binding of biochemical signals occurs, and if so, on time scales relevant to microbial growth and communication. We examined biochar sorption of N-3-oxo-dodecanoyl-L-homoserine lactone, an acyl-homoserine lactone (AHL) intercellular signaling molecule used by many gram-negative soil microbes to regulate gene expression. We show that wood biochars disrupt communication within a growing multicellular system that is made up of sender cells that synthesize AHL and receiver cells that express green fluorescent protein in response to an AHL signal. However, biochar inhibition of AHL-mediated cell-cell communication varied, with the biochar prepared at 700°C (surface area of 301 m2/g) inhibiting cellular communication 10-fold more than an equivalent mass of biochar prepared at 300°C (surface area of 3 m2/g). These findings provide the first direct evidence that biochars elicit a range of effects on gene expression dependent on intercellular signaling, implicating the method of biochar preparation as a parameter that could be tuned to regulate microbial-dependent soil processes, like nitrogen fixation and pest attack of root crops. PMID:24066613

  15. The Novel Roles of Connexin Channels and Tunneling Nanotubes in Cancer Pathogenesis

    PubMed Central

    Valdebenito, Silvana; Lou, Emil; Baldoni, John

    2018-01-01

    Neoplastic growth and cellular differentiation are critical hallmarks of tumor development. It is well established that cell-to-cell communication between tumor cells and “normal” surrounding cells regulates tumor differentiation and proliferation, aggressiveness, and resistance to treatment. Nevertheless, the mechanisms that result in tumor growth and spread as well as the adaptation of healthy surrounding cells to the tumor environment are poorly understood. A major component of these communication systems is composed of connexin (Cx)-containing channels including gap junctions (GJs), tunneling nanotubes (TNTs), and hemichannels (HCs). There are hundreds of reports about the role of Cx-containing channels in the pathogenesis of cancer, and most of them demonstrate a downregulation of these proteins. Nonetheless, new data demonstrate that a localized communication via Cx-containing GJs, HCs, and TNTs plays a key role in tumor growth, differentiation, and resistance to therapies. Moreover, the type and downstream effects of signals communicated between the different populations of tumor cells are still unknown. However, new approaches such as artificial intelligence (AI) and machine learning (ML) could provide new insights into these signals communicated between connected cells. We propose that the identification and characterization of these new communication systems and their associated signaling could provide new targets to prevent or reduce the devastating consequences of cancer. PMID:29695070

  16. Organelle communication: signaling crossroads between homeostasis and disease.

    PubMed

    Bravo-Sagua, Roberto; Torrealba, Natalia; Paredes, Felipe; Morales, Pablo E; Pennanen, Christian; López-Crisosto, Camila; Troncoso, Rodrigo; Criollo, Alfredo; Chiong, Mario; Hill, Joseph A; Simmen, Thomas; Quest, Andrew F; Lavandero, Sergio

    2014-05-01

    Cellular organelles do not function as isolated or static units, but rather form dynamic contacts between one another that can be modulated according to cellular needs. The physical interfaces between organelles are important for Ca2+ and lipid homeostasis, and serve as platforms for the control of many essential functions including metabolism, signaling, organelle integrity and execution of the apoptotic program. Emerging evidence also highlights the importance of organelle communication in disorders such as Alzheimer's disease, pulmonary arterial hypertension, cancer, skeletal and cardiac muscle dysfunction. Here, we provide an overview of the current literature on organelle communication and the link to human pathologies. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Network Coding in Relay-based Device-to-Device Communications

    PubMed Central

    Huang, Jun; Gharavi, Hamid; Yan, Huifang; Xing, Cong-cong

    2018-01-01

    Device-to-Device (D2D) communications has been realized as an effective means to improve network throughput, reduce transmission latency, and extend cellular coverage in 5G systems. Network coding is a well-established technique known for its capability to reduce the number of retransmissions. In this article, we review state-of-the-art network coding in relay-based D2D communications, in terms of application scenarios and network coding techniques. We then apply two representative network coding techniques to dual-hop D2D communications and present an efficient relay node selecting mechanism as a case study. We also outline potential future research directions, according to the current research challenges. Our intention is to provide researchers and practitioners with a comprehensive overview of the current research status in this area and hope that this article may motivate more researchers to participate in developing network coding techniques for different relay-based D2D communications scenarios. PMID:29503504

  18. Long-distance communication by specialized cellular projections during pigment pattern development and evolution

    PubMed Central

    Eom, Dae Seok; Bain, Emily J; Patterson, Larissa B; Grout, Megan E; Parichy, David M

    2015-01-01

    Changes in gene activity are essential for evolutionary diversification. Yet, elucidating the cellular behaviors that underlie modifications to adult form remains a profound challenge. We use neural crest-derived adult pigmentation of zebrafish and pearl danio to uncover cellular bases for alternative pattern states. We show that stripes in zebrafish require a novel class of thin, fast cellular projection to promote Delta-Notch signaling over long distances from cells of the xanthophore lineage to melanophores. Projections depended on microfilaments and microtubules, exhibited meandering trajectories, and stabilized on target cells to which they delivered membraneous vesicles. By contrast, the uniformly patterned pearl danio lacked such projections, concomitant with Colony stimulating factor 1-dependent changes in xanthophore differentiation that likely curtail signaling available to melanophores. Our study reveals a novel mechanism of cellular communication, roles for differentiation state heterogeneity in pigment cell interactions, and an unanticipated morphogenetic behavior contributing to a striking difference in adult form. DOI: http://dx.doi.org/10.7554/eLife.12401.001 PMID:26701906

  19. Future Prospects of Health Management Systems Using Cellular Phones

    PubMed Central

    Kim, Hun-Sung; Hwang, Yunji; Lee, Jae-Ho; Oh, Hye Young; Kim, Yi-Jun; Kwon, Hyeon Yoon; Kang, Hyoseung; Kim, Hyunah; Park, Rae Woong

    2014-01-01

    Abstract Background: Cellular phones enable communication between healthcare providers and patients for prevention, diagnosis, and treatment of diseases. However, few studies have examined the user-friendliness or effectiveness of cellular phone-based medical informatics (CPBMI) for healthcare. Materials and Methods: This study investigated the use of CPBMI to identify its current status within the medical field, advantages and disadvantages, practicability, clinical effectiveness, costs, and cost-saving potential. Results: CPBMI was validated in terms of practicality and provision of medical benefits. It is critical to use CPBMI in accordance with the different features of each disease and condition. Use of CPBMI is expected to be especially useful for patients with chronic disease. Conclusions: We discussed the current status of the clinical use, benefits, and risks of CPBMI. CPBMI and information technology–based health management tools are anticipated to become useful and effective components of healthcare management in the future. PMID:24693986

  20. Protecting the retinal neurons from glaucoma: lowering ocular pressure is not enough.

    PubMed

    Pascale, Alessia; Drago, Filippo; Govoni, Stefano

    2012-07-01

    The retina is theater of a number of biochemical reactions allowing, within its layers, the conversion of light impulses into electrical signals. The axons of the last neuronal elements, the ganglion cells, form the optic nerve and transfer the signals to the brain. Therefore, an appropriate cellular communication, not only within the different retinal cells, but also between the retina itself and the other brain structures, is fundamental. One of the most diffuse pathologies affecting retinal function and communication, which thus reverberates in the whole visual system, is glaucoma. This insidious disease is characterized by a progressive optic nerve degeneration and sight loss which may finally lead to irreversible blindness. Nevertheless, the progressive nature of this pathology offers an opportunity for therapeutic intervention. To better understand the cellular processes implicated in the development of glaucoma useful to envision a targeted pharmacological strategy, this manuscript first examines the complex cellular and functional organization of the retina and subsequently identifies the targets sensitive to neurodegeneration. Within this context, high ocular pressure represents a key risk factor. However, recent literature findings highlight the concept that lowering ocular pressure is not enough to prevent/slow down glaucomatous damage, suggesting the importance of combining the hypotensive treatment with other pharmacological approaches, such as the use of neuroprotectants. Therefore, this important and more novel aspect is extensively considered in this review, also emphasizing the idea that the neuroprotective strategy should be extended to the entire visual system and not restricted to the retina. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. How Stem Cells Speak with Host Immune Cells in Inflammatory Brain Diseases

    PubMed Central

    Pluchino, Stefano; Cossetti, Chiara

    2014-01-01

    Advances in stem cell biology have raised great expectations that diseases and injuries of the central nervous system (CNS) may be ameliorated by the development of non-hematopoietic stem cell medicines. Yet, the application of adult stem cells as CNS therapeutics is challenging and the interpretation of some of the outcomes ambiguous. In fact, the initial idea that stem cell transplants work only via structural cell replacement has been challenged by the observation of consistent cellular signaling between the graft and the host. Cellular signaling is the foundation of coordinated actions and flexible responses, and arises via networks of exchanging and interacting molecules that transmit patterns of information between cells. Sustained stem cell graft-to-host communication leads to remarkable trophic effects on endogenous brain cells and beneficial modulatory actions on innate and adaptive immune responses in vivo, ultimately promoting the healing of the injured CNS. Among a number of adult stem cell types, mesenchymal stem cells (MSCs) and neural stem/precursor cells (NPCs) are being extensively investigated for their ability to signal to the immune system upon transplantation in experimental CNS diseases. Here, we focus on the main cellular signaling pathways that grafted MSCs and NPCs use to establish a therapeutically relevant cross talk with host immune cells, while examining the role of inflammation in regulating some of the bidirectionality of these communications. We propose that the identification of the players involved in stem cell signaling might contribute to the development of innovative, high clinical impact therapeutics for inflammatory CNS diseases. PMID:23633288

  2. Smart Bandwidth Assignation in an Underlay Cellular Network for Internet of Vehicles.

    PubMed

    de la Iglesia, Idoia; Hernandez-Jayo, Unai; Osaba, Eneko; Carballedo, Roberto

    2017-09-27

    The evolution of the IoT (Internet of Things) paradigm applied to new scenarios as VANETs (Vehicular Ad Hoc Networks) has gained momentum in recent years. Both academia and industry have triggered advanced studies in the IoV (Internet of Vehicles), which is understood as an ecosystem where different types of users (vehicles, elements of the infrastructure, pedestrians) are connected. How to efficiently share the available radio resources among the different types of eligible users is one of the important issues to be addressed. This paper briefly analyzes various concepts presented hitherto in the literature and it proposes an enhanced algorithm for ensuring a robust co-existence of the aforementioned system users. Therefore, this paper introduces an underlay RRM (Radio Resource Management) methodology which is capable of (1) improving cellular spectral efficiency while making a minimal impact on cellular communications and (2) ensuring the different QoS (Quality of Service) requirements of ITS (Intelligent Transportation Systems) applications. Simulation results, where we compare the proposed algorithm to the other two RRM, show the promising spectral efficiency performance of the proposed RRM methodology.

  3. Smart Bandwidth Assignation in an Underlay Cellular Network for Internet of Vehicles

    PubMed Central

    de la Iglesia, Idoia; Hernandez-Jayo, Unai

    2017-01-01

    The evolution of the IoT (Internet of Things) paradigm applied to new scenarios as VANETs (Vehicular Ad Hoc Networks) has gained momentum in recent years. Both academia and industry have triggered advanced studies in the IoV (Internet of Vehicles), which is understood as an ecosystem where different types of users (vehicles, elements of the infrastructure, pedestrians) are connected. How to efficiently share the available radio resources among the different types of eligible users is one of the important issues to be addressed. This paper briefly analyzes various concepts presented hitherto in the literature and it proposes an enhanced algorithm for ensuring a robust co-existence of the aforementioned system users. Therefore, this paper introduces an underlay RRM (Radio Resource Management) methodology which is capable of (1) improving cellular spectral efficiency while making a minimal impact on cellular communications and (2) ensuring the different QoS (Quality of Service) requirements of ITS (Intelligent Transportation Systems) applications. Simulation results, where we compare the proposed algorithm to the other two RRM, show the promising spectral efficiency performance of the proposed RRM methodology. PMID:28953256

  4. Focus on the emerging new fields of network physiology and network medicine

    NASA Astrophysics Data System (ADS)

    Ivanov, Plamen Ch; Liu, Kang K. L.; Bartsch, Ronny P.

    2016-10-01

    Despite the vast progress and achievements in systems biology and integrative physiology in the last decades, there is still a significant gap in understanding the mechanisms through which (i) genomic, proteomic and metabolic factors and signaling pathways impact vertical processes across cells, tissues and organs leading to the expression of different disease phenotypes and influence the functional and clinical associations between diseases, and (ii) how diverse physiological systems and organs coordinate their functions over a broad range of space and time scales and horizontally integrate to generate distinct physiologic states at the organism level. Two emerging fields, network medicine and network physiology, aim to address these fundamental questions. Novel concepts and approaches derived from recent advances in network theory, coupled dynamical systems, statistical and computational physics show promise to provide new insights into the complexity of physiological structure and function in health and disease, bridging the genetic and sub-cellular level with inter-cellular interactions and communications among integrated organ systems and sub-systems. These advances form first building blocks in the methodological formalism and theoretical framework necessary to address fundamental problems and challenges in physiology and medicine. This ‘focus on’ issue contains 26 articles representing state-of-the-art contributions covering diverse systems from the sub-cellular to the organism level where physicists have key role in laying the foundations of these new fields.

  5. Vehicular-networking- and road-weather-related research in Sodankylä

    NASA Astrophysics Data System (ADS)

    Sukuvaara, Timo; Mäenpää, Kari; Ylitalo, Riika

    2016-10-01

    Vehicular-networking- and especially safety-related wireless vehicular services have been under intensive research for almost a decade now. Only in recent years has road weather information also been acknowledged to play an important role when aiming to reduce traffic accidents and fatalities via intelligent transport systems (ITSs). Part of the progress can be seen as a result of the Finnish Meteorological Institute's (FMI) long-term research work in Sodankylä within the topic, originally started in 2006. Within multiple research projects, the FMI Arctic Research Centre has been developing wireless vehicular networking and road weather services, in co-operation with the FMI meteorological services team in Helsinki. At the beginning the wireless communication was conducted with traditional Wi-Fi type local area networking, but during the development the system has evolved into a hybrid communication system of a combined vehicular ad hoc networking (VANET) system with special IEEE 802.11p protocol and supporting cellular networking based on a commercial 3G network, not forgetting support for Wi-Fi-based devices also. For piloting purposes and further research, we have established a special combined road weather station (RWS) and roadside unit (RSU), to interact with vehicles as a service hotspot. In the RWS-RSU we have chosen to build support to all major approaches, IEEE 802.11, traditional Wi-Fi and cellular 3G. We employ road weather systems of FMI, along with RWS and vehicle data gathered from vehicles, in the up-to-date localized weather data delivered in real time. IEEE 802.11p vehicular networking is supported with Wi-Fi and 3G communications. This paper briefly introduces the research work related to vehicular networking and road weather services conducted in Sodankylä, as well as the research project involved in this work. The current status of instrumentation, available services and capabilities are presented in order to formulate a clear general view of the research field.

  6. Mutant Analysis Reveals Allosteric Regulation of ClpB Disaggregase

    PubMed Central

    Franke, Kamila B.; Bukau, Bernd; Mogk, Axel

    2017-01-01

    The members of the hexameric AAA+ disaggregase of E. coli and S. cerevisiae, ClpB, and Hsp104, cooperate with the Hsp70 chaperone system in the solubilization of aggregated proteins. Aggregate solubilization relies on a substrate threading activity of ClpB/Hsp104 fueled by ATP hydrolysis in both ATPase rings (AAA-1, AAA-2). ClpB/Hsp104 ATPase activity is controlled by the M-domains, which associate to the AAA-1 ring to downregulate ATP hydrolysis. Keeping M-domains displaced from the AAA-1 ring by association with Hsp70 increases ATPase activity due to enhanced communication between protomers. This communication involves conserved arginine fingers. The control of ClpB/Hsp104 activity is crucial, as hyperactive mutants with permanently dissociated M-domains exhibit cellular toxicity. Here, we analyzed AAA-1 inter-ring communication in relation to the M-domain mediated ATPase regulation, by subjecting a conserved residue of the AAA-1 domain subunit interface of ClpB (A328) to mutational analysis. While all A328X mutants have reduced disaggregation activities, their ATPase activities strongly differed. ClpB-A328I/L mutants have reduced ATPase activity and when combined with the hyperactive ClpB-K476C M-domain mutation, suppress cellular toxicity. This underlines that ClpB ATPase activation by M-domain dissociation relies on increased subunit communication. The ClpB-A328V mutant in contrast has very high ATPase activity and exhibits cellular toxicity on its own, qualifying it as novel hyperactive ClpB mutant. ClpB-A328V hyperactivity is however, different from that of M-domain mutants as M-domains stay associated with the AAA-1 ring. The high ATPase activity of ClpB-A328V primarily relies on the AAA-2 ring and correlates with distinct conformational changes in the AAA-2 catalytic site. These findings characterize the subunit interface residue A328 as crucial regulatory element to control ATP hydrolysis in both AAA rings. PMID:28275610

  7. An improved broadband E patch microstrip antenna for wireless communications

    NASA Astrophysics Data System (ADS)

    Bzeih, Amer; Chahine, Soubhi Abou; Kabalan, Karim Y.; El-Hajj, Ali; Chehab, Ali

    2007-12-01

    A broadband probe-fed microstrip antenna with E-shaped patch on a single-layer air substrate is investigated. Bandwidth enhancement of the antenna is achieved by inserting two parallel slots into its radiating patch. The effects of the antenna parameters are analyzed, and their optimal values for broadband operation are obtained. The design parameters are formulated as a function of the center frequency, and the empirical equations are validated by simulation. A 51.5% enhanced E patch antenna for modern wireless communications (Personal Communications Service, Digital Cellular System, Universal Mobile Telecommunications System, Wireless Local Area Network 802.11 b/g, and Bluetooth) is designed, simulated, fabricated, and measured. A comparison between simulated and measured results is presented, and it showed satisfactory agreement. Moreover, the effect of incorporating more parallel slots into the radiating patch is investigated. The antenna is designed and simulated for different scenarios (four slots, six slots, and eight slots), where a bandwidth of 57% is achieved in the eight-slot design.

  8. Keeping Communications Flowing During Large-Scale Disasters: Leveraging Amateur Radio Innovations for Disaster Medicine

    PubMed Central

    Cid, Victor H.; Mitz, Andrew R.; Arnesen, Stacey J.

    2017-01-01

    Medical facilities may struggle to maintain effective communications during a major disaster. Natural and man-made disasters threaten connectivity by degrading or crippling Internet, cellular/mobile, and landline telephone services across wide areas. Communications among staff, between facilities, and to resources outside the disaster area may be lost for an extended time. A prototype communications system created by the National Library of Medicine (NLM) provides basic communication services that ensure essential connectivity in the face of widespread infrastructure loss. It leverages Amateur Radio to provide resilient email service to local users, enabling them to reach intact communications networks outside the disaster zone. Because Amateur Radio is inexpensive, always available, and sufficiently independent of terrestrial telecommunications infrastructure, it has often augmented telecommunications capabilities of medical facilities. NLM’s solution is unique in that it provides end-user to end-user direct email communications, without requiring the intervention of a radio operator in the handling of the messages. Medical staff can exchange email among themselves and with others outside the communications blackout zone. The technology is portable, deployable on short notice, and can be powered in a variety of ways to adapt to the crisis’ circumstances. PMID:28944749

  9. Cellular Telephone Use: A Survey of College Business Students

    ERIC Educational Resources Information Center

    Braguglia, Kay H.

    2008-01-01

    Whether it is hand held, in a pocket, on a backpack, clipped to a belt, or hidden in a brief case or purse, college students and cellular telephones go together. Communication with fellow students, professors, parents, and everyone else is just a click away. While walking across campus and down the halls of academic buildings, cellular telephones…

  10. 47 CFR 22.970 - Unacceptable interference to part 90 non-cellular 800 MHz licensees from cellular radiotelephone...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 22.970 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.970 Unacceptable interference to part 90 non... −104 dBm or higher, as measured at the R.F. input of the receiver of a mobile unit; or (B) A median...

  11. Evolution of Microbial Quorum Sensing to Human Global Quorum Sensing: An Insight into How Gap Junctional Intercellular Communication Might Be Linked to the Global Metabolic Disease Crisis

    PubMed Central

    Trosko, James E.

    2016-01-01

    The first anaerobic organism extracted energy for survival and reproduction from its source of nutrients, with the genetic means to ensure protection of its individual genome but also its species survival. While it had a means to communicate with its community via simple secreted molecules (“quorum sensing”), the eventual shift to an aerobic environment led to multi-cellular metazoan organisms, with evolutionary-selected genes to form extracellular matrices, stem cells, stem cell niches, and a family of gap junction or “connexin” genes. These germinal and somatic stem cells responded to extracellular signals that triggered intra-cellular signaling to regulate specific genes out of the total genome. These extra-cellular induced intra-cellular signals also modulated gap junctional intercellular communication (GJIC) in order to regulate the new cellular functions of symmetrical and asymmetrical cell division, cell differentiation, modes of cell death, and senescence. Within the hierarchical and cybernetic concepts, differentiated by neurons organized in the brain of the Homo sapiens, the conscious mind led to language, abstract ideas, technology, myth-making, scientific reasoning, and moral decision–making, i.e., the creation of culture. Over thousands of years, this has created the current collision between biological and cultural evolution, leading to the global “metabolic disease” crisis. PMID:27314399

  12. Space Industry Study Industrial College of the Armed Forces National Defense University

    DTIC Science & Technology

    2002-06-01

    information technologies , especially fiber, cable, and cellular communications, which forced space systems away from old market roles and denied entry to... technologies fill market niches. As technology matures, small satellites have been viewed a partial solution to this cycle, enabling faster programs...years, the largely unforeseen growth in the internet has proven a valuable new market for satellite service providers. And over the past few years

  13. 47 CFR 2.1093 - Radiofrequency radiation exposure evaluation: portable devices.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Cellular Radiotelephone Service pursuant to part 22 of this chapter; the Personal Communications Service (PCS) pursuant to part 24 of this chapter; the Satellite Communications Services pursuant to part 25 of this chapter; the Miscellaneous Wireless Communications Services pursuant to part 27 of this chapter...

  14. 10 Years of Car-2-X Communication - a Success Story?

    NASA Astrophysics Data System (ADS)

    Wischhof, Lars; Ebner, André

    2012-05-01

    For more than ten years, car-2-x communication has been a major topic of research in the scientific community and an important development focus for the automotive industry. First, this article takes a retrospective look at the evolution of car-2-x and the two different communication paradigms: decentralized car-2-car communication and centralized cellular solutions. Afterwards, a comparison of their technical advantages and limitations is presented, respectively. The result shows that in order to implement safety-relevant applications, car-2-car communication has strong advantages compared to cellular technologies but requires high market penetration. However, its introduction solely for safety applications is difficult since the required penetration will not be achieved until several years after initial deployment. Therefore, car-2-car communication must provide a benefit to the customer, even in the phase of market introduction. For this purpose, the article outlines an approach called SODAD (Segment-Oriented Data Abstraction and Dissemination). It offers a possibility to introduce decentralized vehicular applications with early customer benefit, in order to enable safety applications based on car-2-car communication on a long term.

  15. Extracellular Vesicles from Neural Stem Cells Transfer IFN-γ via Ifngr1 to Activate Stat1 Signaling in Target Cells

    PubMed Central

    Cossetti, Chiara; Iraci, Nunzio; Mercer, Tim R.; Leonardi, Tommaso; Alpi, Emanuele; Drago, Denise; Alfaro-Cervello, Clara; Saini, Harpreet K.; Davis, Matthew P.; Schaeffer, Julia; Vega, Beatriz; Stefanini, Matilde; Zhao, CongJian; Muller, Werner; Garcia-Verdugo, Jose Manuel; Mathivanan, Suresh; Bachi, Angela; Enright, Anton J.; Mattick, John S.; Pluchino, Stefano

    2015-01-01

    SUMMARY The idea that stem cell therapies work only via cell replacement is challenged by the observation of consistent intercellular molecule exchange between the graft and the host. Here we defined a mechanism of cellular signaling by which neural stem/precursor cells (NPCs) communicate with the microenvironment via extracellular vesicles (EVs), and we elucidated its molecular signature and function. We observed cytokine-regulated pathways that sort proteins and mRNAs into EVs. We described induction of interferon gamma (IFN-γ) pathway in NPCs exposed to proinflammatory cytokines that is mirrored in EVs. We showed that IFN-γ bound to EVs through Ifngr1 activates Stat1 in target cells. Finally, we demonstrated that endogenous Stat1 and Ifngr1 in target cells are indispensable to sustain the activation of Stat1 signaling by EV-associated IFN-γ/Ifngr1 complexes. Our study identifies a mechanism of cellular signaling regulated by EV-associated IFN-γ/Ifngr1 complexes, which grafted stem cells may use to communicate with the host immune system. PMID:25242146

  16. The ELLIPSO (tm) system: Elliptical low orbits for mobile communications and other optimum system elements

    NASA Technical Reports Server (NTRS)

    Castiel, David

    1991-01-01

    On 5 Nov. 1990, Ellipsat filed with the FCC the first application to provide voice communication services via low earth orbiting (LEO) satellites. The proposed system, ELLIPSO, aims at achieving end-user costs comparable to those in the cellular industry. On 3 Jun. 1991 Ellipsat filed for the second complement of its system. Ellipsat was also the first company to propose combined position determination and mobile voice services via low-earth orbiting satellites. Ellipsat is still the only proponent of elliptical orbits for any commercial system in the United States. ELLIPSO uses a spectrum efficient combination of FDMA and CDMA techniques. Ellipsat's strategy is to tailor required capacity to user demand, reduce initial system costs and investment risks, and allow the provision of services at affordable end-user prices. ELLIPSO offers optimum features in all the components of its system, elliptical orbits, small satellites, integrated protocol and signalling system, integrated end-user electronics, novel marketing approach based on the cooperation with the tenets of mobile communications, end-user costs that are affordable, and a low risk approach as deployment is tailored to the growth of its customer base. The efficient design of the ELLIPSO constellation and system allows estimated end-user costs in the $.50 per minute range, five to six times less than any other system of comparable capability.

  17. The Vertebrate Brain, Evidence of Its Modular Organization and Operating System: Insights into the Brain's Basic Units of Structure, Function, and Operation and How They Influence Neuronal Signaling and Behavior.

    PubMed

    Baslow, Morris H

    2011-01-01

    The human brain is a complex organ made up of neurons and several other cell types, and whose role is processing information for use in eliciting behaviors. However, the composition of its repeating cellular units for both structure and function are unresolved. Based on recent descriptions of the brain's physiological "operating system", a function of the tri-cellular metabolism of N-acetylaspartate (NAA) and N-acetylaspartylglutamate (NAAG) for supply of energy, and on the nature of "neuronal words and languages" for intercellular communication, insights into the brain's modular structural and functional units have been gained. In this article, it is proposed that the basic structural unit in brain is defined by its physiological operating system, and that it consists of a single neuron, and one or more astrocytes, oligodendrocytes, and vascular system endothelial cells. It is also proposed that the basic functional unit in the brain is defined by how neurons communicate, and consists of two neurons and their interconnecting dendritic-synaptic-dendritic field. Since a functional unit is composed of two neurons, it requires two structural units to form a functional unit. Thus, the brain can be envisioned as being made up of the three-dimensional stacking and intertwining of myriad structural units which results not only in its gross structure, but also in producing a uniform distribution of binary functional units. Since the physiological NAA-NAAG operating system for supply of energy is repeated in every structural unit, it is positioned to control global brain function.

  18. A mitochondria-selective near-infrared-emitting fluorescent dye for cellular imaging studies.

    PubMed

    Choi, Peter; Noguchi, Katsuya; Ishiyama, Munetaka; Denny, William A; Jose, Jiney

    2018-05-03

    This communication details the synthesis, evaluation of photophysical properties, and cellular imaging studies of cyanine chromophore based fluorescent dye 1 as a selective imaging agent for mitochondria. Copyright © 2018 Elsevier Ltd. All rights reserved.

  19. Fuzzy-cellular neural network for face recognition HCI Authentication

    NASA Astrophysics Data System (ADS)

    Hoomod, Haider K.; ali, Ahmed abd

    2018-05-01

    Because of the rapid development of mobile devices technology, ease of use and interact with humans. May have found a mobile device most uses in our communications. Mobile devices can carry large amounts of personal and sensitive data, but often left not guaranteed (pin) locks are inconvenient to use and thus have seen low adoption while biometrics is more convenient and less susceptible to fraud and manipulation. Were propose in this paper authentication technique for using a mobile face recognition based on cellular neural networks [1] and fuzzy rules control. The good speed and get recognition rate from applied the proposed system in Android system. The images obtained in real time for 60 persons each person has 20 t0 60 different shot face images (about 3600 images), were the results for (FAR = 0), (FRR = 1.66%), (FER = 1.66) and accuracy = 98.34

  20. Land mobile satellite services in Europe

    NASA Astrophysics Data System (ADS)

    Bartholomé, P.; Berretta, G.; Rogard, R.

    The demand for land-mobile communications on a Europe-wide basis is an important and pressing problem. The pan-European cellular network now in the planning stage will be slow in coming and it will have its limitations. A regional satellite system for Europe to complement the cellular network is the only practical way to satisfy a specialised market that encompasses a population of several hundred thousand mobiles, including road vehicles, merchant shipping, fishing boats, and trains. The deployment of a regional system would take place in a number of phases, the first being based on a simple payload embarked on a host satellite belonging to a European organisation. Further phases will involve the development of more advanced payloads on dedicated satellites. For the long-term future, the use of satellites in highly inclined orbits is being considered as a means of improving their visibility and hence the service quality.

  1. Origin of life: LUCA and extracellular membrane vesicles (EMVs)

    NASA Astrophysics Data System (ADS)

    Gill, S.; Forterre, P.

    2016-01-01

    Cells from the three domains of life produce extracellular membrane vesicles (EMVs), suggesting that EMV production is an important aspect of cellular physiology. EMVs have been implicated in many aspects of cellular life in all domains, including stress response, toxicity against competing strains, pathogenicity, detoxification and resistance against viral attack. These EMVs represent an important mode of inter-cellular communication by serving as vehicles for transfer of DNA, RNA, proteins and lipids between cells. Here, we review recent progress in the understanding of EMV biology and their various roles. We focus on the role of membrane vesicles in early cellular evolution and how they would have helped shape the nature of the last universal common ancestor. A membrane-protected micro-environment would have been a key to the survival of spontaneous molecular systems and efficient metabolic reactions. Interestingly, the morphology of EMVs is strongly reminiscent of the morphology of some virions. It is thus tempting to make a link between the origin of the first protocell via the formation of vesicles and the origin of viruses.

  2. Polymorphous computing fabric

    DOEpatents

    Wolinski, Christophe Czeslaw [Los Alamos, NM; Gokhale, Maya B [Los Alamos, NM; McCabe, Kevin Peter [Los Alamos, NM

    2011-01-18

    Fabric-based computing systems and methods are disclosed. A fabric-based computing system can include a polymorphous computing fabric that can be customized on a per application basis and a host processor in communication with said polymorphous computing fabric. The polymorphous computing fabric includes a cellular architecture that can be highly parameterized to enable a customized synthesis of fabric instances for a variety of enhanced application performances thereof. A global memory concept can also be included that provides the host processor random access to all variables and instructions associated with the polymorphous computing fabric.

  3. A-21st-century-approach to firefighting in the Western US: How microwave-based seismic networks can change fire suppression from reactive to proactive

    NASA Astrophysics Data System (ADS)

    Kent, G. M.; Smith, K. D.; Williams, M. C.; Slater, D. E.; Plank, G.; McCarthy, M.; Rojas-Gonzalez, R.; Vernon, F.; Driscoll, N. W.; Hidley, G.

    2015-12-01

    The Nevada Seismological Laboratory (NSL) at UNR has recently embarked on a bold technical initiative, installing a high-speed (up to 190 Mb/sec) mountaintop-based Internet Protocol (IP) microwave network, enabling a myriad of sensor systems for Multi-Hazard Early Warning detection and response. In the Tahoe Basin, this system is known as AlertTahoe; a similar network has been deployed in north-central Nevada as part of a 5-year-long grant with BLM. The UNR network mirrors the successful HPWREN multi-hazard network run through UCSD; the UNR "Alert" program (Access to Leverage Emergency information in Real Time) has expanded on the original concept by providing a framework for early fire detection and discovery. Both systems do not rely on open-access public Internet services such as those provided by cellular service providers. Instead, they utilize private wireless communication networks to collect data 24/7 in real-time from multiple sensors throughout the system. Utilizing this restricted-access private communication platform enhances system reliability, capability, capacity and versatility for staff and its community of certified users. Both UNR and UCSD fire camera systems are presently being confederated under a common framework to provide end users (e.g., BLM, USFS, CalFire) a unified interface. Earthquake response has been both organizations' primary mission for decades; high-speed IP microwave fundamentally changes the playing field allowing for rapid early detection of wildfires, earthquakes and other natural disasters, greatly improving local and regional disaster response/recovery. For example, networked cameras can be optimally placed for wildfire detection and are significantly less vulnerable due infrastructure hardening and the ability to avoid extreme demands by the public on cellular and other public networks during a crisis. These systems also provide a backup for emergency responders to use when public access communications become overwhelmed or fail during an event. The crowd-sourced fire cameras can be viewed year round through AlertTahoe and AlertSoCal websites with on-demand time-lapse, an integrated real time lightning map, and other useful features.

  4. Inter-Cellular Exchange of Cellular Components via VE-Cadherin-Dependent Trans-Endocytosis

    PubMed Central

    Sakurai, Takashi; Woolls, Melissa J.; Jin, Suk-Won

    2014-01-01

    Cell-cell communications typically involve receptor-mediated signaling initiated by soluble or cell-bound ligands. Here, we report a unique mode of endocytosis: proteins originating from cell-cell junctions and cytosolic cellular components from the neighboring cell are internalized, leading to direct exchange of cellular components between two adjacent endothelial cells. VE-cadherins form transcellular bridges between two endothelial cells that are the basis of adherence junctions. At such adherens junction sites, we observed the movement of the entire VE-cadherin molecule from one endothelial cell into the other with junctional and cytoplasmic components. This phenomenon, here termed trans-endocytosis, requires the establishment of a VE-cadherin homodimer in trans with internalization proceeding in a Rac1-, and actomyosin-dependent manner. Importantly, the trans-endocytosis is not dependent on any known endocytic pathway including clathrin-dependent endocytosis, macropinocytosis or phagocytosis. This novel form of cell-cell communications, leading to a direct exchange of cellular components, was observed in 2D and 3D-cultured endothelial cells as well as in the developing zebrafish vasculature. PMID:24603875

  5. KODAMA and VPC based Framework for Ubiquitous Systems and its Experiment

    NASA Astrophysics Data System (ADS)

    Takahashi, Kenichi; Amamiya, Satoshi; Iwao, Tadashige; Zhong, Guoqiang; Kainuma, Tatsuya; Amamiya, Makoto

    Recently, agent technologies have attracted a lot of interest as an emerging programming paradigm. With such agent technologies, services are provided through collaboration among agents. At the same time, the spread of mobile technologies and communication infrastructures has made it possible to access the network anytime and from anywhere. Using agents and mobile technologies to realize ubiquitous computing systems, we propose a new framework based on KODAMA and VPC. KODAMA provides distributed management mechanisms by using the concept of community and communication infrastructure to deliver messages among agents without agents being aware of the physical network. VPC provides a method of defining peer-to-peer services based on agent communication with policy packages. By merging the characteristics of both KODAMA and VPC functions, we propose a new framework for ubiquitous computing environments. It provides distributed management functions according to the concept of agent communities, agent communications which are abstracted from the physical environment, and agent collaboration with policy packages. Using our new framework, we conducted a large-scale experiment in shopping malls in Nagoya, which sent advertisement e-mails to users' cellular phones according to user location and attributes. The empirical results showed that our new framework worked effectively for sales in shopping malls.

  6. Methodology For The System Integration Of Adaptive Resilience In Armor

    DTIC Science & Technology

    2016-09-01

    military FM radio . Military FM radios operate in a set mode of frequencies . In today’s modern era, many other pathways of digital and analogue... communication exist, whether cellular network, satellite, or even the aging telephone lines. The common FM radio uses line-of-sight electromagnetic...Jackson 2009). Apollo 13 was to be the third intentional U.S.-manned lunar landing. The craft was launched on April 11 , 1970, from the Kennedy Space

  7. Integrated biocircuits: engineering functional multicellular circuits and devices.

    PubMed

    Prox, Jordan; Smith, Tory; Holl, Chad; Chehade, Nick; Guo, Liang

    2018-04-01

    Implantable neurotechnologies have revolutionized neuromodulatory medicine for treating the dysfunction of diseased neural circuitry. However, challenges with biocompatibility and lack of full control over neural network communication and function limits the potential to create more stable and robust neuromodulation devices. Thus, we propose a platform technology of implantable and programmable cellular systems, namely Integrated Biocircuits, which use only cells as the functional components of the device. We envision the foundational principles for this concept begins with novel in vitro platforms used for the study and reconstruction of cellular circuitry. Additionally, recent advancements in organoid and 3D culture systems account for microenvironment factors of cytoarchitecture to construct multicellular circuits as they are normally formed in the brain. We explore the current state of the art of these platforms to provide knowledge of their advancements in circuit fabrication and identify the current biological principles that could be applied in designing integrated biocircuit devices. We have highlighted the exemplary methodologies and techniques of in vitro circuit fabrication and propose the integration of selected controllable parameters, which would be required in creating suitable biodevices. We provide our perspective and propose new insights into the future of neuromodulaion devices within the scope of living cellular systems that can be applied in designing more reliable and biocompatible stimulation-based neuroprosthetics.

  8. Integrated biocircuits: engineering functional multicellular circuits and devices

    NASA Astrophysics Data System (ADS)

    Prox, Jordan; Smith, Tory; Holl, Chad; Chehade, Nick; Guo, Liang

    2018-04-01

    Objective. Implantable neurotechnologies have revolutionized neuromodulatory medicine for treating the dysfunction of diseased neural circuitry. However, challenges with biocompatibility and lack of full control over neural network communication and function limits the potential to create more stable and robust neuromodulation devices. Thus, we propose a platform technology of implantable and programmable cellular systems, namely Integrated Biocircuits, which use only cells as the functional components of the device. Approach. We envision the foundational principles for this concept begins with novel in vitro platforms used for the study and reconstruction of cellular circuitry. Additionally, recent advancements in organoid and 3D culture systems account for microenvironment factors of cytoarchitecture to construct multicellular circuits as they are normally formed in the brain. We explore the current state of the art of these platforms to provide knowledge of their advancements in circuit fabrication and identify the current biological principles that could be applied in designing integrated biocircuit devices. Main results. We have highlighted the exemplary methodologies and techniques of in vitro circuit fabrication and propose the integration of selected controllable parameters, which would be required in creating suitable biodevices. Significance. We provide our perspective and propose new insights into the future of neuromodulaion devices within the scope of living cellular systems that can be applied in designing more reliable and biocompatible stimulation-based neuroprosthetics.

  9. Intercellular communication via gap junctions affected by mechanical load in the bovine annulus fibrosus.

    PubMed

    Desrochers, Jane; Duncan, Neil A

    2014-01-01

    Cells in the intervertebral disc, as in other connective tissues including tendon, ligament and bone, form interconnected cellular networks that are linked via functional gap junctions. These cellular networks may be necessary to affect a coordinated response to mechanical and environmental stimuli. Using confocal microscopy with fluorescence recovery after photobleaching methods, we explored the in situ strain environment of the outer annulus of an intact bovine disc and the effect of high-level flexion on gap junction signalling. The in situ strain environment in the extracellular matrix of the outer annulus under high flexion load was observed to be non-uniform with the extensive cellular processes remaining crimped sometimes at flexion angles greater than 25°. A significant transient disruption of intercellular communication via functional gap junctions was measured after 10 and 20 min under high flexion load. This study illustrates that in healthy annulus fibrosus tissue, high mechanical loads can impede the functioning of the gap junctions. Future studies will explore more complex loading conditions to determine whether losses in intercellular communication can be permanent and whether gap junctions in aged and degenerated tissues become more susceptible to load. The current research suggests that cellular structures such as gap junctions and intercellular networks, as well as other cell-cell and cell-matrix interconnections, need to be considered in computational models in order to fully understand how macroscale mechanical signals are transmitted across scales to the microscale and ultimately into a cellular biosynthetic response in collagenous tissues.

  10. Dynamics of Cellular Responses to Radiation

    PubMed Central

    Wodarz, Dominik; Sorace, Ron; Komarova, Natalia L.

    2014-01-01

    Understanding the consequences of exposure to low dose ionizing radiation is an important public health concern. While the risk of low dose radiation has been estimated by extrapolation from data at higher doses according to the linear non-threshold model, it has become clear that cellular responses can be very different at low compared to high radiation doses. Important phenomena in this respect include radioadaptive responses as well as low-dose hyper-radiosensitivity (HRS) and increased radioresistance (IRR). With radioadaptive responses, low dose exposure can protect against subsequent challenges, and two mechanisms have been suggested: an intracellular mechanism, inducing cellular changes as a result of the priming radiation, and induction of a protected state by inter-cellular communication. We use mathematical models to examine the effect of these mechanisms on cellular responses to low dose radiation. We find that the intracellular mechanism can account for the occurrence of radioadaptive responses. Interestingly, the same mechanism can also explain the existence of the HRS and IRR phenomena, and successfully describe experimentally observed dose-response relationships for a variety of cell types. This indicates that different, seemingly unrelated, low dose phenomena might be connected and driven by common core processes. With respect to the inter-cellular communication mechanism, we find that it can also account for the occurrence of radioadaptive responses, indicating redundancy in this respect. The model, however, also suggests that the communication mechanism can be vital for the long term survival of cell populations that are continuously exposed to relatively low levels of radiation, which cannot be achieved with the intracellular mechanism in our model. Experimental tests to address our model predictions are proposed. PMID:24722167

  11. Common MD-IS infrastructure for wireless data technologies

    NASA Astrophysics Data System (ADS)

    White, Malcolm E.

    1995-12-01

    The expansion of global networks, caused by growth and acquisition within the commercial sector, is forcing users to move away from proprietary systems in favor of standards-based, open systems architectures. The same is true in the wireless data communications arena, where operators of proprietary wireless data networks have endeavored to convince users that their particular implementation provides the best service. However, most of the vendors touting these solutions have failed to gain the critical mass that might have lead to their technologies' adoption as a defacto standard, and have been held back by a lack of applications and the high cost of mobile devices. The advent of the cellular digital packet data (CDPD) specification and its support by much of the public cellular service industry has set the stage for the ubiquitous coverage of wireless packet data services across the Unites States. Although CDPD was developed for operation over the advanced mobile phone system (AMPS) cellular network, many of the defined protocols are industry standards that can be applied to the construction of a common infrastructure supporting multiple airlink standards. This approach offers overall cost savings and operation efficiency for service providers, hardware, and software developers and end-users alike, and could be equally advantageous for those service operators using proprietary end system protocols, should they wish to migrate towards an open standard.

  12. Communication technology in trauma centers: a national survey.

    PubMed

    Xiao, Yan; Kim, Young-Ju; Gardner, Sharyn D; Faraj, Samer; MacKenzie, Colin F

    2006-01-01

    The relationship between information and communication technology (ICT) and trauma work coordination has long been recognized. The purpose of the study was to investigate the type and frequency of use of various ICTs to activate and organize trauma teams in level I/II trauma centers. In a cross-sectional survey, questionnaires were mailed to trauma directors and clinicians in 457 trauma centers in the United States. Responses were received from 254 directors and 767 clinicians. Communication with pre-hospital care providers was conducted predominantly via shortwave radio (67.3%). The primary communication methods used to reach trauma surgeons were manual (56.7%) and computerized group page (36.6%). Computerized group page (53.7%) and regular telephone (49.8%) were cited as the most advantageous devices; e-mail (52.3%) and dry erase whiteboard (52.1%) were selected as the least advantageous. Attending surgeons preferred less overhead paging and more cellular phone communication than did emergency medicine physicians and nurses. Cellular phones have become an important part of hospital-field communication. In high-volume trauma centers, there is a need for more accurate methods of communicating with field personnel and among hospital care providers.

  13. Bi-directional exchange of membrane components occurs during co-culture of mesenchymal stem cells and nucleus pulposus cells.

    PubMed

    Strassburg, Sandra; Hodson, Nigel W; Hill, Patrick I; Richardson, Stephen M; Hoyland, Judith A

    2012-01-01

    Mesenchymal stem cell (MSC)-based therapies have been proposed as novel treatments for intervertebral disc (IVD) degeneration. We have previously demonstrated that when MSCs are co-cultured with nucleus pulposus (NP) cells with direct cell-cell contact, they differentiate along the NP lineage and simultaneously stimulate the degenerate NP cell population to regain a normal (non-degenerate) phenotype, an effect which requires cell-cell communication. However, the mechanisms by which NP cells and MSCs interact in this system are currently unclear. Thus, in this study we investigated a range of potential mechanisms for exchange of cellular components or information that may direct these changes, including cell fusion, gap-junctional communication and exchange of membrane components by direct transfer or via microvesicle formation. Flow cytometry of fluorescently labeled MSCs and NP cells revealed evidence of some cell fusion and formation of gapjunctions, although at the three timepoints studied these phenomena were detectable only in a small proportion of cells. While these mechanisms may play a role in cell-cell communication, the data suggests they are not the predominant mechanism of interaction. However, flow cytometry of fluorescently dual-labeled cells showed that extensive bi-directional transfer of membrane components is operational during direct co-culture of MSCs and NP cells. Furthermore, there was also evidence for secretion and internalization of membrane-bound microvesicles by both cell types. Thus, this study highlights bi-directional intercellular transfer of membrane components as a possible mechanism of cellular communication between MSC and NP cells.

  14. Keeping Communications Flowing During Large-scale Disasters: Leveraging Amateur Radio Innovations for Disaster Medicine.

    PubMed

    Cid, Victor H; Mitz, Andrew R; Arnesen, Stacey J

    2018-04-01

    Medical facilities may struggle to maintain effective communications during a major disaster. Natural and man-made disasters threaten connectivity by degrading or crippling Internet, cellular/mobile, and landline telephone services across wide areas. Communications among staff, between facilities, and to resources outside the disaster area may be lost for an extended time. A prototype communications system created by the National Library of Medicine (NLM) provides basic communication services that ensure essential connectivity in the face of widespread infrastructure loss. It leverages amateur radio to provide resilient email service to local users, enabling them to reach intact communications networks outside the disaster zone. Because amateur radio is inexpensive, always available, and sufficiently independent of terrestrial telecommunications infrastructure, it has often augmented telecommunications capabilities of medical facilities. NLM's solution is unique in that it provides end-user to end-user direct email communications, without requiring the intervention of a radio operator in the handling of the messages. Medical staff can exchange email among themselves and with others outside the communications blackout zone. The technology is portable, is deployable on short notice, and can be powered in a variety of ways to adapt to the circumstances of each crisis. (Disaster Med Public Health Preparedness. 2018;12:257-264).

  15. A GPS-based Real-time Road Traffic Monitoring System

    NASA Astrophysics Data System (ADS)

    Tanti, Kamal Kumar

    In recent years, monitoring systems are astonishingly inclined towards ever more automatic; reliably interconnected, distributed and autonomous operation. Specifically, the measurement, logging, data processing and interpretation activities may be carried out by separate units at different locations in near real-time. The recent evolution of mobile communication devices and communication technologies has fostered a growing interest in the GIS & GPS-based location-aware systems and services. This paper describes a real-time road traffic monitoring system based on integrated mobile field devices (GPS/GSM/IOs) working in tandem with advanced GIS-based application software providing on-the-fly authentications for real-time monitoring and security enhancement. The described system is developed as a fully automated, continuous, real-time monitoring system that employs GPS sensors and Ethernet and/or serial port communication techniques are used to transfer data between GPS receivers at target points and a central processing computer. The data can be processed locally or remotely based on the requirements of client’s satisfaction. Due to the modular architecture of the system, other sensor types may be supported with minimal effort. Data on the distributed network & measurements are transmitted via cellular SIM cards to a Control Unit, which provides for post-processing and network management. The Control Unit may be remotely accessed via an Internet connection. The new system will not only provide more consistent data about the road traffic conditions but also will provide methods for integrating with other Intelligent Transportation Systems (ITS). For communication between the mobile device and central monitoring service GSM technology is used. The resulting system is characterized by autonomy, reliability and a high degree of automation.

  16. Exosomal and Non-Exosomal Transport of Extra-Cellular microRNAs in Follicular Fluid: Implications for Bovine Oocyte Developmental Competence

    PubMed Central

    Sohel, Md. Mahmodul Hasan; Hoelker, Michael; Noferesti, Sina Seifi; Salilew-Wondim, Dessie; Tholen, Ernst; Looft, Christian; Rings, Franca; Uddin, Muhammad Jasim; Spencer, Thomas E.; Schellander, Karl; Tesfaye, Dawit

    2013-01-01

    Cell-cell communication within the follicle involves many signaling molecules, and this process may be mediated by secretion and uptake of exosomes that contain several bioactive molecules including extra-cellular miRNAs. Follicular fluid and cells from individual follicles of cattle were grouped based on Brilliant Cresyl Blue (BCB) staining of the corresponding oocytes. Both Exoquick precipitation and differential ultracentrifugation were used to separate the exosome and non-exosomal fraction of follicular fluid. Following miRNA isolation from both fractions, the human miRCURY LNA™ Universal RT miRNA PCR array system was used to profile miRNA expression. This analysis found that miRNAs were present in both exosomal and non-exosomal fraction of bovine follicular fluid. We found 25 miRNAs differentially expressed (16 up and 9 down) in exosomes and 30 miRNAs differentially expressed (21 up and 9 down) in non-exosomal fraction of follicular fluid in comparison of BCB- versus BCB+ oocyte groups. Expression of selected miRNAs was detected in theca, granulosa and cumulus oocyte complex. To further explore the potential roles of these follicular fluid derived extra-cellular miRNAs, the potential target genes were predicted, and functional annotation and pathway analysis revealed most of these pathways are known regulators of follicular development and oocyte growth. In order to validate exosome mediated cell-cell communication within follicular microenvironment, we demonstrated uptake of exosomes and resulting increase of endogenous miRNA level and subsequent alteration of mRNA levels in follicular cells in vitro. This study demonstrates for the first time, the presence of exosome or non-exosome mediated transfer of miRNA in the bovine follicular fluid, and oocyte growth dependent variation in extra-cellular miRNA signatures in the follicular environment. PMID:24223816

  17. Experimental demonstration of bindingless signal delivery in human cells via microfluidics

    NASA Astrophysics Data System (ADS)

    Kuo, Ching-Te; Chuang, Fang-Tzu; Wu, Pei-Yi; Lin, Yueh-Chien; Liu, Hao-Kai; Huang, Guan-Syuan; Tsai, Tzu-Ching; Chi, Cheng-Yu; Wo, Andrew M.; Lee, Hsinyu; Lee, Si-Chen

    2014-07-01

    The cellular signal transduction is commonly believed to rely on the direct "contact" or "binding" of the participating molecule reaction that depends positively on the corresponding molecule concentrations. In living systems, however, it is somewhat difficult to precisely match the corresponding rapid "binding," depending on the probability of molecular collision, existing in the cellular receptor-ligand interactions. Thus, a question arises that if there is another mechanism (i.e., bindingless) that could promote this signal communication. According to this hypothesis, we report a cellular model based on the examination of intracellular calcium concentration to explore whether the unidentified signal delivery in cells exists, via a microfluidic device. This device was designed to isolate the cells from directly contacting with the corresponding ligands/molecules by the particular polydimethylsiloxane (PDMS) membranes with different thicknesses. Results show a significant increment of calcium mobilization in human prostate cancer PC-3 cells by the stimulation of endothelin-1, even up to a separated distance of 95 μm. In addition, these stimulated signals exhibited a bump-shaped characteristics depending on the membrane thickness. When the PDMS membrane is capped by SiO2, a particular trait that resembles the ballistic signal conduction was observed. A theoretical model was developed to describe the signal transport process across the PDMS membrane. Taken together, these results indicate that the unidentified signal (ligand structural information) delivery could occur in cells and be examined by the proposed approach, exhibiting a bindingless communication manner. Moreover, this approach and our finding may offer new opportunities to establish a robust and cost-effective platform for the study of cellular biology and new drug development.

  18. Cellular Signaling Networks Function as Generalized Wiener-Kolmogorov Filters to Suppress Noise

    NASA Astrophysics Data System (ADS)

    Hinczewski, Michael; Thirumalai, D.

    2014-10-01

    Cellular signaling involves the transmission of environmental information through cascades of stochastic biochemical reactions, inevitably introducing noise that compromises signal fidelity. Each stage of the cascade often takes the form of a kinase-phosphatase push-pull network, a basic unit of signaling pathways whose malfunction is linked with a host of cancers. We show that this ubiquitous enzymatic network motif effectively behaves as a Wiener-Kolmogorov optimal noise filter. Using concepts from umbral calculus, we generalize the linear Wiener-Kolmogorov theory, originally introduced in the context of communication and control engineering, to take nonlinear signal transduction and discrete molecule populations into account. This allows us to derive rigorous constraints for efficient noise reduction in this biochemical system. Our mathematical formalism yields bounds on filter performance in cases important to cellular function—such as ultrasensitive response to stimuli. We highlight features of the system relevant for optimizing filter efficiency, encoded in a single, measurable, dimensionless parameter. Our theory, which describes noise control in a large class of signal transduction networks, is also useful both for the design of synthetic biochemical signaling pathways and the manipulation of pathways through experimental probes such as oscillatory input.

  19. Preface: cardiac control pathways: signaling and transport phenomena.

    PubMed

    Sideman, Samuel

    2008-03-01

    Signaling is part of a complex system of communication that governs basic cellular functions and coordinates cellular activity. Transfer of ions and signaling molecules and their interactions with appropriate receptors, transmembrane transport, and the consequent intracellular interactions and functional cellular response represent a complex system of interwoven phenomena of transport, signaling, conformational changes, chemical activation, and/or genetic expression. The well-being of the cell thus depends on a harmonic orchestration of all these events and the existence of control mechanisms that assure the normal behavior of the various parameters involved and their orderly expression. The ability of cells to sustain life by perceiving and responding correctly to their microenvironment is the basis for development, tissue repair, and immunity, as well as normal tissue homeostasis. Natural deviations, or human-induced interference in the signaling pathways and/or inter- and intracellular transport and information transfer, are responsible for the generation, modulation, and control of diseases. The present overview aims to highlight some major topics of the highly complex cellular information transfer processes and their control mechanisms. Our goal is to contribute to the understanding of the normal and pathophysiological phenomena associated with cardiac functions so that more efficient therapeutic modalities can be developed. Our objective in this volume is to identify and enhance the study of some basic passive and active physical and chemical transport phenomena, physiological signaling pathways, and their biological consequences.

  20. 47 CFR 22.909 - Cellular markets.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Cellular markets. 22.909 Section 22.909 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES... counties they comprise are listed in Public Notice Report No. CL-92-40 “Common Carrier Public Mobile...

  1. 47 CFR 22.909 - Cellular markets.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Cellular markets. 22.909 Section 22.909 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES... counties they comprise are listed in Public Notice Report No. CL-92-40 “Common Carrier Public Mobile...

  2. 47 CFR 22.909 - Cellular markets.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Cellular markets. 22.909 Section 22.909 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES... counties they comprise are listed in Public Notice Report No. CL-92-40 “Common Carrier Public Mobile...

  3. Interspecies chemical communication in bacterial development.

    PubMed

    Straight, Paul D; Kolter, Roberto

    2009-01-01

    Our view of bacteria, from the earliest observations through the heyday of antibiotic discovery, has shifted dramatically. We recognize communities of bacteria as integral and functionally important components of diverse habitats, ranging from soil collectives to the human microbiome. To function as productive communities, bacteria coordinate metabolic functions, often requiring shifts in growth and development. The hallmark of cellular development, which we characterize as physiological change in response to environmental stimuli, is a defining feature of many bacterial interspecies interactions. Bacterial communities rely on chemical exchanges to provide the cues for developmental change. Traditional methods in microbiology focus on isolation and characterization of bacteria in monoculture, separating the organisms from the surroundings in which interspecies chemical communication has relevance. Developing multispecies experimental systems that incorporate knowledge of bacterial physiology and metabolism with insights from biodiversity and metagenomics shows great promise for understanding interspecies chemical communication in the microbial world.

  4. Zoledronate promotes bone formation by blocking osteocyte-osteoblast communication during bone defect healing.

    PubMed

    Cui, Pingping; Liu, Hongrui; Sun, Jing; Amizuka, Norio; Sun, Qinfeng; Li, Minqi

    2018-01-01

    Nitrogen-containing bisphosphonates (N-BPs) are potent antiresorptive drugs and their actions on osteoclasts have been studied extensively. Recent studies have suggested that N-BPs also target bone-forming cells. However, the precise mechanism of N-BPs in osteoblasts is paradoxical, and the specific role of osteocytes is worthy of in-depth study. Here, we investigated the cellular mechanisms of N-BPs regulating bone defect healing by zoledronate (ZA). Bone histomorphometry confirmed an increase in new bone formation by systemic ZA administration. ZA induced more alkaline phosphatase-positive osteoblasts and tartrate-resistant acid phosphatase-positive osteoclasts residing on the bone surface. Inexplicably, ZA increased SOST expression in osteocytes embedded in the bone matrix, which was not compatible with the intense osteoblast activity on the bone surface. ZA induced heterogeneous osteocytes and disturbed the distribution of the osteocytic-canalicular system (OLCS). Furthermore, according to the degree of OLCS regularity, dentin matrix protein 1 reactivity had accumulated around osteocytes in the ZA group, but it was distributed evenly in the OLCS of the control group. The control group showed a dense array of the gap junction protein connexin 43. However, connexin 43 was extremely sparse after ZA administration. In summary, ZA treatment reduces gap junction connections and blocks cellular communication between osteocytes and osteoblasts. Retaining SOST expression in osteocytes leads to activation of the Wnt signaling pathway and subsequent bone formation.

  5. Indoor/Outdoor Seamless Positioning Using Lighting Tags and GPS Cellular Phones for Personal Navigation

    NASA Astrophysics Data System (ADS)

    Namie, Hiromune; Morishita, Hisashi

    The authors focused on the development of an indoor positioning system which is easy to use, portable and available for everyone. This system is capable of providing the correct position anywhere indoors, including onboard ships, and was invented in order to evaluate the availability of GPS indoors. Although the performance of GPS is superior outdoors, there has been considerable research regarding indoor GPS involving sensitive GPS, pseudolites (GPS pseudo satellite), RFID (Radio Frequency IDentification) tags, and wireless LAN .However, the positioning rate and the precision are not high enough for general use, which is the reason why these technologies have not yet spread to personal navigation systems. In this regard, the authors attempted to implement an indoor positioning system using cellular phones with built-in GPS and infrared light data communication functionality, which are widely used in Japan. GPS is becoming increasingly popular, where GPGGS sentences of the NMEA outputted from the GPS receiver provide spatiotemporal information including latitude, longitude, altitude, and time or ECEF xyz coordinates. As GPS applications grow rapidly, spatiotemporal data becomes key to the ubiquitous outdoor and indoor seamless positioning services at least for the entire area of Japan, as well as to becoming familiar with satellite positioning systems (e.g. GPS). Furthermore, the authors are also working on the idea of using PDAs (Personal Digital Assistants), as cellular phones with built-in GPS and PDA functionality are also becoming increasingly popular.

  6. Gas Main Sensor and Communications Network System

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

    Hagen Schempf

    Automatika, Inc. was contracted by the Department of Energy (DOE) and with co-funding from the Northeast Gas Association (NGA), to develop an in-pipe natural gas prototype measurement and wireless communications system for assessing and monitoring distribution networks. This projected was completed in April 2006, and culminated in the installation of more than 2 dozen GasNet nodes in both low- and high-pressure cast-iron and steel mains owned by multiple utilities in the northeastern US. Utilities are currently logging data (off-line) and monitoring data in real time from single and multiple networked sensors over cellular networks and collecting data using wireless bluetoothmore » PDA systems. The system was designed to be modular, using in-pipe sensor-wands capable of measuring, flow, pressure, temperature, water-content and vibration. Internal antennae allowed for the use of the pipe-internals as a waveguide for setting up a sensor network to collect data from multiple nodes simultaneously. Sensor nodes were designed to be installed with low- and no-blow techniques and tools. Using a multi-drop bus technique with a custom protocol, all electronics were designed to be buriable and allow for on-board data-collection (SD-card), wireless relaying and cellular network forwarding. Installation options afforded by the design included direct-burial and external polemounted variants. Power was provided by one or more batteries, direct AC-power (Class I Div.2) and solar-array. The utilities are currently in a data-collection phase and intend to use the collected (and processed) data to make capital improvement decisions, compare it to Stoner model predictions and evaluate the use of such a system for future expansion, technology-improvement and commercialization starting later in 2006.« less

  7. Biomaterials-Based Electronics: Polymers and Interfaces for Biology and Medicine

    PubMed Central

    Muskovich, Meredith; Bettinger, Christopher J.

    2012-01-01

    Advanced polymeric biomaterials continue to serve as a cornerstone of new medical technologies and therapies. The vast majority of these materials, both natural and synthetic, interact with biological matter without direct electronic communication. However, biological systems have evolved to synthesize and employ naturally-derived materials for the generation and modulation of electrical potentials, voltage gradients, and ion flows. Bioelectric phenomena can be interpreted as potent signaling cues for intra- and inter-cellular communication. These cues can serve as a gateway to link synthetic devices with biological systems. This progress report will provide an update on advances in the application of electronically active biomaterials for use in organic electronics and bio-interfaces. Specific focus will be granted to the use of natural and synthetic biological materials as integral components in technologies such as thin film electronics, in vitro cell culture models, and implantable medical devices. Future perspectives and emerging challenges will also be highlighted. PMID:23184740

  8. The role of mitochondria in plant development and stress tolerance

    USDA-ARS?s Scientific Manuscript database

    Proper cellular function requires orchestrated communication among cellular compartments and the ability of the cell to sense and respond to its environment. Plant cells contain three distinct compartments that house DNA. The nucleus contains the nuclear genome, which provides a majority of a cell's...

  9. 77 FR 61535 - Private Land Mobile Radio Rules

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-10

    ... technology that we believe can provide valuable benefits to land mobile radio users. III. Summary of..., GPS equipment, pagers, cellular phones, mobile communications equipment, and radio and television...-114] Private Land Mobile Radio Rules AGENCY: Federal Communications Commission. ACTION: Final rule...

  10. Multiple access techniques and spectrum utilization of the GLOBALSTAR mobile satellite system

    NASA Astrophysics Data System (ADS)

    Louie, Ming; Cohen, Michel; Rouffet, Denis; Gilhousen, Klein S.

    The GLOBALSTAR System is a Low Earth Orbit (LEO) satellite-based mobile communications system that is interoperable with the current and future Public Land Mobile Network (PLMN). The GLOBALSTAR System concept is based upon technological advancement in two key areas: (1) the advancement in LEO satellite technology; (2) the advancement in cellular telephone technology, including the commercial applications of Code Division Multiple Access (CDMA) technologies, and of the most recent progress in Time Division Multiple Access technologies. The GLOBALSTAR System uses elements of CDMA, Frequency Division Multiple Access (FDMA), and Time Division Multiple Access (TDMA) technology, combining with satellite Multiple Beam Antenna (MBA) technology, to arrive at one of the most efficient modulation and multiple access system ever proposed for a satellite communications system. The technology used in GLOBALSTAR exploits the following techniques in obtaining high spectral efficiency and affordable cost per channel, with minimum coordination among different systems: power control, in open and closed loops, voice activation, spot beam satellite antenna for frequency reuse, weighted satellite antenna gain, multiple satellite coverage, and handoff between satellites. The GLOBALSTAR system design will use the following frequency bands: 1610-1626.5 MHz for up-link and 2483.5-2500 MHz for down-link.

  11. Overload Control for Signaling Congestion of Machine Type Communications in 3GPP Networks

    PubMed Central

    Lu, Zhaoming; Pan, Qi; Wang, Luhan; Wen, Xiangming

    2016-01-01

    Because of the limited resources on radio access channels of third generation partnership projection (3GPP) network, one of the most challenging tasks posted by 3GPP cellular-based machine type communications (MTC) is congestion due to massive requests for connection to radio access network (RAN). In this paper, an overload control algorithm in 3GPP RAN is proposed, which proactively disperses the simultaneous access attempts in evenly distributed time window. Through periodic reservation strategy, massive access requests of MTC devices are dispersed in time, which reduces the probability of confliction of signaling. By the compensation and prediction mechanism, each device can communicate with MTC server with dynamic load of air interface. Numerical results prove that proposed method makes MTC applications friendly to 3GPP cellular network. PMID:27936011

  12. Overload Control for Signaling Congestion of Machine Type Communications in 3GPP Networks.

    PubMed

    Lu, Zhaoming; Pan, Qi; Wang, Luhan; Wen, Xiangming

    2016-01-01

    Because of the limited resources on radio access channels of third generation partnership projection (3GPP) network, one of the most challenging tasks posted by 3GPP cellular-based machine type communications (MTC) is congestion due to massive requests for connection to radio access network (RAN). In this paper, an overload control algorithm in 3GPP RAN is proposed, which proactively disperses the simultaneous access attempts in evenly distributed time window. Through periodic reservation strategy, massive access requests of MTC devices are dispersed in time, which reduces the probability of confliction of signaling. By the compensation and prediction mechanism, each device can communicate with MTC server with dynamic load of air interface. Numerical results prove that proposed method makes MTC applications friendly to 3GPP cellular network.

  13. Extracellular vesicles and their synthetic analogues in aging and age-associated brain diseases

    PubMed Central

    Smith, J. A.; Leonardi, T.; Huang, B.; Iraci, N.; Vega, B.; Pluchino, S.

    2015-01-01

    Multicellular organisms rely upon diverse and complex intercellular communications networks for a myriad of physiological processes. Disruption of these processes is implicated in the onset and propagation of disease and disorder, including the mechanisms of senescence at both cellular and organismal levels. In recent years, secreted extracellular vesicles (EVs) have been identified as a particularly novel vector by which cell-to-cell communications are enacted. EVs actively and specifically traffic bioactive proteins, nucleic acids, and metabolites between cells at local and systemic levels, modulating cellular responses in a bidirectional manner under both homeostatic and pathological conditions. EVs are being implicated not only in the generic aging process, but also as vehicles of pathology in a number of age-related diseases, including cancer and neurodegenerative and disease. Thus, circulating EVs—or specific EV cargoes—are being utilised as putative biomarkers of disease. On the other hand, EVs, as targeted intercellular shuttles of multipotent bioactive payloads, have demonstrated promising therapeutic properties, which can potentially be modulated and enhanced through cellular engineering. Furthermore, there is considerable interest in employing nanomedicinal approaches to mimic the putative therapeutic properties of EVs by employing synthetic analogues for targeted drug delivery. Herein we describe what is known about the origin and nature of EVs and subsequently review their putative roles in biology and medicine (including the use of synthetic EV analogues), with a particular focus on their role in aging and age-related brain diseases. PMID:24973266

  14. Extracellular vesicles and their synthetic analogues in aging and age-associated brain diseases.

    PubMed

    Smith, J A; Leonardi, T; Huang, B; Iraci, N; Vega, B; Pluchino, S

    2015-04-01

    Multicellular organisms rely upon diverse and complex intercellular communications networks for a myriad of physiological processes. Disruption of these processes is implicated in the onset and propagation of disease and disorder, including the mechanisms of senescence at both cellular and organismal levels. In recent years, secreted extracellular vesicles (EVs) have been identified as a particularly novel vector by which cell-to-cell communications are enacted. EVs actively and specifically traffic bioactive proteins, nucleic acids, and metabolites between cells at local and systemic levels, modulating cellular responses in a bidirectional manner under both homeostatic and pathological conditions. EVs are being implicated not only in the generic aging process, but also as vehicles of pathology in a number of age-related diseases, including cancer and neurodegenerative and disease. Thus, circulating EVs-or specific EV cargoes-are being utilised as putative biomarkers of disease. On the other hand, EVs, as targeted intercellular shuttles of multipotent bioactive payloads, have demonstrated promising therapeutic properties, which can potentially be modulated and enhanced through cellular engineering. Furthermore, there is considerable interest in employing nanomedicinal approaches to mimic the putative therapeutic properties of EVs by employing synthetic analogues for targeted drug delivery. Herein we describe what is known about the origin and nature of EVs and subsequently review their putative roles in biology and medicine (including the use of synthetic EV analogues), with a particular focus on their role in aging and age-related brain diseases.

  15. Aerospace century XXI: Space sciences, applications, and commercial developments; Proceedings of the Thirty-third Annual AAS International Conference, Boulder, CO, Oct. 26-29, 1986

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

    Morgenthaler, G.W.; Koster, J.N.

    1987-01-01

    Papers are presented on rocket UV observations of Comet Halley, a space system for microgravity research, transitioning from Spacelab to Space Station science, and assemblers and future space hardware. Also considered are spatial and temporal scales of atmospheric disturbances, Doppler radar for prediction and warning, data management for the Columbus program, communications satellites of the future, and commercial launch vehicles. Other topics include space geodesy and earthquake predictions, inverted cellular radio satellite systems, material processing in space, and potential for earth observations from the manned Space Station.

  16. Effectiveness of Using Cellular Phones to Transmit Real-Time Shelter Morbidity Surveillance Data After Hurricane Sandy, New Jersey, October to November, 2012.

    PubMed

    Shumate, Alice M; Yard, Ellen E; Casey-Lockyer, Mary; Apostolou, Andria; Chan, Miranda; Tan, Christina; Noe, Rebecca S; Wolkin, Amy F

    2016-06-01

    Timely morbidity surveillance of sheltered populations is crucial for identifying and addressing their immediate needs, and accurate surveillance allows us to better prepare for future disasters. However, disasters often create travel and communication challenges that complicate the collection and transmission of surveillance data. We describe a surveillance project conducted in New Jersey shelters after Hurricane Sandy, which occurred in November 2012, that successfully used cellular phones for remote real-time reporting. This project demonstrated that, when supported with just-in-time morbidity surveillance training, cellular phone reporting was a successful, sustainable, and less labor-intensive methodology than in-person shelter visits to capture morbidity data from multiple locations and opened a two-way communication channel with shelters. (Disaster Med Public Health Preparedness. 2015;10:525-528).

  17. Technology Assessment for the Future Aeronautical Communications System

    NASA Technical Reports Server (NTRS)

    Budinger, James M. (Technical Monitor)

    2005-01-01

    To address emerging saturation in the VHF aeronautical bands allocated internationally for air traffic management communications, the International Civil Aviation Organization (ICAO) has requested development of a common global solution through its Aeronautical Communications Panel (ACP). In response, the Federal Aviation Administration (FAA) and Eurocontrol initiated a joint study, with the support of NASA and U.S. and European contractors, to provide major findings on alternatives and recommendations to the ICAO ACP Working Group C (WG-C). Under an FAA/Eurocontrol cooperative research and development agreement, ACP WG-C Action Plan 17 (AP-17), commonly referred to as the Future Communications Study (FCS), NASA Glenn Research Center is responsible for the investigation of potential communications technologies that support the long-term mobile communication operational concepts of the FCS. This report documents the results of the first phase of the technology assessment and recommendations referred to in the Technology Pre-Screening Task 3.1 of AP-17. The prescreening identifies potential technologies that are under development in the industry and provides an initial assessment against a harmonized set of evaluation criteria that address high level capabilities, projected maturity for the time frame for usage in aviation, and potential applicability to aviation. A wide variety of candidate technologies were evaluated from several communications service categories including: cellular telephony; IEEE-802.xx standards; public safety radio; satellite and over-the-horizon communications; custom narrowband VHF; custom wideband; and military communications.

  18. The impact of cellular senescence in skin ageing: A notion of mosaic and therapeutic strategies.

    PubMed

    Toutfaire, Marie; Bauwens, Emilie; Debacq-Chainiaux, Florence

    2017-10-15

    Cellular senescence is now recognized as one of the nine hallmarks of ageing. Recent data show the involvement of senescent cells in tissue ageing and some age-related diseases. Skin represents an ideal model for the study of ageing. Indeed, skin ageing varies between individuals depending on their chronological age but also on their exposure to various exogenous factors (mainly ultraviolet rays). If senescence traits can be detected with ageing in the skin, the senescent phenotype varies among the various skin cell types. Moreover, the origin of cellular senescence in the skin is still unknown, and multiple origins are possible. This reflects the mosaic of skin ageing. Senescent cells can interfere with their microenvironment, either via the direct secretion of factors (the senescence-associated secretory phenotype) or via other methods of communication, such as extracellular vesicles. Knowledge regarding the impact of cellular senescence on skin ageing could be integrated into dermatology research, especially to limit the appearance of senescent cells after photo(chemo)therapy or in age-related skin diseases. Therapeutic approaches include the clearance of senescent cells via the use of senolytics or via the cooperation with the immune system. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Dynamical and Mechanistic Reconstructive Approaches of T Lymphocyte Dynamics: Using Visual Modeling Languages to Bridge the Gap between Immunologists, Theoreticians, and Programmers

    PubMed Central

    Thomas-Vaslin, Véronique; Six, Adrien; Ganascia, Jean-Gabriel; Bersini, Hugues

    2013-01-01

    Dynamic modeling of lymphocyte behavior has primarily been based on populations based differential equations or on cellular agents moving in space and interacting each other. The final steps of this modeling effort are expressed in a code written in a programing language. On account of the complete lack of standardization of the different steps to proceed, we have to deplore poor communication and sharing between experimentalists, theoreticians and programmers. The adoption of diagrammatic visual computer language should however greatly help the immunologists to better communicate, to more easily identify the models similarities and facilitate the reuse and extension of existing software models. Since immunologists often conceptualize the dynamical evolution of immune systems in terms of “state-transitions” of biological objects, we promote the use of unified modeling language (UML) state-transition diagram. To demonstrate the feasibility of this approach, we present a UML refactoring of two published models on thymocyte differentiation. Originally built with different modeling strategies, a mathematical ordinary differential equation-based model and a cellular automata model, the two models are now in the same visual formalism and can be compared. PMID:24101919

  20. Noisy transcription factor NF-κB oscillations stabilize and sensitize cytokine signaling in space

    NASA Astrophysics Data System (ADS)

    Gangstad, Sirin W.; Feldager, Cilie W.; Juul, Jeppe; Trusina, Ala

    2013-02-01

    NF-κB is a major transcription factor mediating inflammatory response. In response to a pro-inflammatory stimulus, it exhibits a characteristic response—a pulse followed by noisy oscillations in concentrations of considerably smaller amplitude. NF-κB is an important mediator of cellular communication, as it is both activated by and upregulates production of cytokines, signals used by white blood cells to find the source of inflammation. While the oscillatory dynamics of NF-κB has been extensively investigated both experimentally and theoretically, the role of the noise and the lower secondary amplitude has not been addressed. We use a cellular automaton model to address these issues in the context of spatially distributed communicating cells. We find that noisy secondary oscillations stabilize concentric wave patterns, thus improving signal quality. Furthermore, both lower secondary amplitude as well as noise in the oscillation period might be working against chronic inflammation, the state of self-sustained and stimulus-independent excitations. Our findings suggest that the characteristic irregular secondary oscillations of lower amplitude are not accidental. On the contrary, they might have evolved to increase robustness of the inflammatory response and the system's ability to return to a pre-stimulated state.

  1. Monitoring Extracellular Vesicle Cargo Active Uptake by Imaging Flow Cytometry.

    PubMed

    Ofir-Birin, Yifat; Abou Karam, Paula; Rudik, Ariel; Giladi, Tal; Porat, Ziv; Regev-Rudzki, Neta

    2018-01-01

    Extracellular vesicles are essential for long distance cell-cell communication. They function as carriers of different compounds, including proteins, lipids and nucleic acids. Pathogens, like malaria parasites ( Plasmodium falciparum, Pf ), excel in employing vesicle release to mediate cell communication in diverse processes, particularly in manipulating the host response. Establishing research tools to study the interface between pathogen-derived vesicles and their host recipient cells will greatly benefit the scientific community. Here, we present an imaging flow cytometry (IFC) method for monitoring the uptake of malaria-derived vesicles by host immune cells. By staining different cargo components, we were able to directly track the cargo's internalization over time and measure the kinetics of its delivery. Impressively, we demonstrate that this method can be used to specifically monitor the translocation of a specific protein within the cellular milieu upon internalization of parasitic cargo; namely, we were able to visually observe how uptaken parasitic Pf -DNA cargo leads to translocation of transcription factor IRF3 from the cytosol to the nucleus within the recipient immune cell. Our findings demonstrate that our method can be used to study cellular dynamics upon vesicle uptake in different host-pathogen and pathogen-pathogen systems.

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

    Kuruganti, Phani Teja

    The smart grid is a combined process of revitalizing the traditional power grid applications and introducing new applications to improve the efficiency of power generation, transmission and distribution. This can be achieved by leveraging advanced communication and networking technologies. Therefore the selection of the appropriate communication technology for different smart grid applications has been debated a lot in the recent past. After comparing different possible technologies, a recent research study has arrived at a conclusion that the 3G cellular technology is the right choice for distribution side smart grid applications like smart metering, advanced distribution automation and demand response managementmore » system. In this paper, we argue that the current 3G/4G cellular technologies are not an appropriate choice for smart grid distribution applications and propose a Hybrid Spread Spectrum (HSS) based Advanced Metering Infrastructure (AMI) as one of the alternatives to 3G/4G technologies. We present a preliminary PHY and MAC layer design of a HSS based AMI network and evaluate their performance using matlab and NS2 simulations. Also, we propose a time hierarchical scheme that can significantly reduce the volume of random access traffic generated during blackouts and the delay in power outage reporting.« less

  3. 47 CFR 2.1091 - Radiofrequency radiation exposure evaluation: mobile devices.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...: mobile devices. 2.1091 Section 2.1091 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL... workers that can be easily re-located, such as wireless devices associated with a personal computer, are... that operate in the Cellular Radiotelephone Service, the Personal Communications Services, the...

  4. PDAs and the Library Without a Roof.

    ERIC Educational Resources Information Center

    Foster, Clifton Dale

    1995-01-01

    A project demonstrated the feasibility of accessing library information (online public access catalogs, commercial online databases, Internet) from a distance using handheld personal digital assistants (PDAs) equipped with cellular communication capability. The study is described, and other uses of wireless communications in libraries and…

  5. Safe use of cellular telephones in hospitals: fundamental principles and case studies.

    PubMed

    Cohen, Ted; Ellis, Willard S; Morrissey, Joseph J; Bakuzonis, Craig; David, Yadin; Paperman, W David

    2005-01-01

    Many industries and individuals have embraced cellular telephones. They provide mobile, synchronous communication, which could hypothetically increase the efficiency and safety of inpatient healthcare. However, reports of early analog cellular telephones interfering with critical life-support machines had led many hospitals to strictly prohibit cellular telephones. A literature search revealed that individual hospitals now are allowing cellular telephone use with various policies to prevent electromagnetic interference with medical devices. The fundamental principles underlying electromagnetic interference are immunity, frequency, modulation technology, distance, and power Electromagnetic interference risk mitigation methods based on these principles have been successfully implemented. In one case study, a minimum distance between cellular telephones and medical devices is maintained, with restrictions in critical areas. In another case study, cellular telephone coverage is augmented to automatically control the power of the cellular telephone. While no uniform safety standard yet exists, cellular telephones can be safely used in hospitals when their use is managed carefully.

  6. Heterogeneous Wireless Networks for Smart Grid Distribution Systems: Advantages and Limitations.

    PubMed

    Khalifa, Tarek; Abdrabou, Atef; Shaban, Khaled; Gaouda, A M

    2018-05-11

    Supporting a conventional power grid with advanced communication capabilities is a cornerstone to transferring it to a smart grid. A reliable communication infrastructure with a high throughput can lay the foundation towards the ultimate objective of a fully automated power grid with self-healing capabilities. In order to realize this objective, the communication infrastructure of a power distribution network needs to be extended to cover all substations including medium/low voltage ones. This shall enable information exchange among substations for a variety of system automation purposes with a low latency that suits time critical applications. This paper proposes the integration of two heterogeneous wireless technologies (such as WiFi and cellular 3G/4G) to provide reliable and fast communication among primary and secondary distribution substations. This integration allows the transmission of different data packets (not packet replicas) over two radio interfaces, making these interfaces act like a one data pipe. Thus, the paper investigates the applicability and effectiveness of employing heterogeneous wireless networks (HWNs) in achieving the desired reliability and timeliness requirements of future smart grids. We study the performance of HWNs in a realistic scenario under different data transfer loads and packet loss ratios. Our findings reveal that HWNs can be a viable data transfer option for smart grids.

  7. Heterogeneous Wireless Networks for Smart Grid Distribution Systems: Advantages and Limitations

    PubMed Central

    Khalifa, Tarek; Abdrabou, Atef; Gaouda, A. M.

    2018-01-01

    Supporting a conventional power grid with advanced communication capabilities is a cornerstone to transferring it to a smart grid. A reliable communication infrastructure with a high throughput can lay the foundation towards the ultimate objective of a fully automated power grid with self-healing capabilities. In order to realize this objective, the communication infrastructure of a power distribution network needs to be extended to cover all substations including medium/low voltage ones. This shall enable information exchange among substations for a variety of system automation purposes with a low latency that suits time critical applications. This paper proposes the integration of two heterogeneous wireless technologies (such as WiFi and cellular 3G/4G) to provide reliable and fast communication among primary and secondary distribution substations. This integration allows the transmission of different data packets (not packet replicas) over two radio interfaces, making these interfaces act like a one data pipe. Thus, the paper investigates the applicability and effectiveness of employing heterogeneous wireless networks (HWNs) in achieving the desired reliability and timeliness requirements of future smart grids. We study the performance of HWNs in a realistic scenario under different data transfer loads and packet loss ratios. Our findings reveal that HWNs can be a viable data transfer option for smart grids. PMID:29751633

  8. Measurements and modelling of base station power consumption under real traffic loads.

    PubMed

    Lorincz, Josip; Garma, Tonko; Petrovic, Goran

    2012-01-01

    Base stations represent the main contributor to the energy consumption of a mobile cellular network. Since traffic load in mobile networks significantly varies during a working or weekend day, it is important to quantify the influence of these variations on the base station power consumption. Therefore, this paper investigates changes in the instantaneous power consumption of GSM (Global System for Mobile Communications) and UMTS (Universal Mobile Telecommunications System) base stations according to their respective traffic load. The real data in terms of the power consumption and traffic load have been obtained from continuous measurements performed on a fully operated base station site. Measurements show the existence of a direct relationship between base station traffic load and power consumption. According to this relationship, we develop a linear power consumption model for base stations of both technologies. This paper also gives an overview of the most important concepts which are being proposed to make cellular networks more energy-efficient.

  9. Measurements and Modelling of Base Station Power Consumption under Real Traffic Loads †

    PubMed Central

    Lorincz, Josip; Garma, Tonko; Petrovic, Goran

    2012-01-01

    Base stations represent the main contributor to the energy consumption of a mobile cellular network. Since traffic load in mobile networks significantly varies during a working or weekend day, it is important to quantify the influence of these variations on the base station power consumption. Therefore, this paper investigates changes in the instantaneous power consumption of GSM (Global System for Mobile Communications) and UMTS (Universal Mobile Telecommunications System) base stations according to their respective traffic load. The real data in terms of the power consumption and traffic load have been obtained from continuous measurements performed on a fully operated base station site. Measurements show the existence of a direct relationship between base station traffic load and power consumption. According to this relationship, we develop a linear power consumption model for base stations of both technologies. This paper also gives an overview of the most important concepts which are being proposed to make cellular networks more energy-efficient. PMID:22666026

  10. Multiplexed mass cytometry profiling of cellular states perturbed by small-molecule regulators

    PubMed Central

    Bodenmiller, Bernd; Zunder, Eli R.; Finck, Rachel; Chen, Tiffany J.; Savig, Erica S.; Bruggner, Robert V.; Simonds, Erin F.; Bendall, Sean C.; Sachs, Karen; Krutzik, Peter O.; Nolan, Garry P.

    2013-01-01

    The ability to comprehensively explore the impact of bio-active molecules on human samples at the single-cell level can provide great insight for biomedical research. Mass cytometry enables quantitative single-cell analysis with deep dimensionality, but currently lacks high-throughput capability. Here we report a method termed mass-tag cellular barcoding (MCB) that increases mass cytometry throughput by sample multiplexing. 96-well format MCB was used to characterize human peripheral blood mononuclear cell (PBMC) signaling dynamics, cell-to-cell communication, the signaling variability between 8 donors, and to define the impact of 27 inhibitors on this system. For each compound, 14 phosphorylation sites were measured in 14 PBMC types, resulting in 18,816 quantified phosphorylation levels from each multiplexed sample. This high-dimensional systems-level inquiry allowed analysis across cell-type and signaling space, reclassified inhibitors, and revealed off-target effects. MCB enables high-content, high-throughput screening, with potential applications for drug discovery, pre-clinical testing, and mechanistic investigation of human disease. PMID:22902532

  11. Forwarding Pointers for Efficient Location Management in Distributed Mobile Environments

    DTIC Science & Technology

    1994-09-01

    signalling trac on the SS7 signalling system(capacity of 56 Kbps) is expected to be 4-11 times greater for cellular networks than for ISDN and3-4 times...load. Thus location updatewill become a major bottleneck at the switches (such as SS7 ) and mechanisms to control the costof location update are...ACM, pp. 19-28, Oct. 1994.16 [3] Kathleen S. Meier-Hellstern, et. al., \\The Use of SS7 and GSM to support high density per-sonal communications

  12. Tip-enhanced Raman scattering of bacillus subtilis spores

    NASA Astrophysics Data System (ADS)

    Rusciano, G.; Zito, G.; Pesce, G.; Sasso, A.; Isticato, R.; Ricca, E.

    2015-07-01

    Understanding of the complex interactions of molecules at biological interfaces is a fundamental issue in biochemistry, biotechnology as well as biomedicine. A plethora of biological processes are ruled by the molecular texture of cellular membrane: cellular communications, drug transportations and cellular recognition are just a few examples of such chemically-mediated processes. Tip-Enhanced Raman Scattering (TERS) is a novel, Raman-based technique which is ideally suited for this purpose. TERS relies on the combination of scanning probe microscopy and Raman spectroscopy. The basic idea is the use of a metalled tip as a sort of optical nano-antenna, which gives place to SERS effect close to the tip end. Herein, we present the application of TERS to analyze the surface of Bacillus subtilis spores. The choice of this biological systems is related to the fact that a number of reasons support the use of spores as a mucosal delivery system. The remarkable and well-documented resistance of spores to various environmental and toxic effects make them clear potentials as a novel, surface-display system. Our experimental outcomes demonstrate that TERS is able to provide a nano-scale chemical imaging of spore surface. Moreover, we demonstrate that TERS allows differentiation between wilde-type spore and genetically modified strains. These results hold promise for the characterization and optimization of spore surface for drug-delivery applications.

  13. 49 CFR 220.301 - Purpose and application.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ..., DEPARTMENT OF TRANSPORTATION RAILROAD COMMUNICATIONS Electronic Devices § 220.301 Purpose and application. (a... or cellular phones) and laptop computers. (b) The applicability of this subpart is governed by § 220.3; this subpart, however, does not affect the use of working wireless communications pursuant to...

  14. 49 CFR 220.301 - Purpose and application.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., DEPARTMENT OF TRANSPORTATION RAILROAD COMMUNICATIONS Electronic Devices § 220.301 Purpose and application. (a... or cellular phones) and laptop computers. (b) The applicability of this subpart is governed by § 220.3; this subpart, however, does not affect the use of working wireless communications pursuant to...

  15. 49 CFR 220.301 - Purpose and application.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., DEPARTMENT OF TRANSPORTATION RAILROAD COMMUNICATIONS Electronic Devices § 220.301 Purpose and application. (a... or cellular phones) and laptop computers. (b) The applicability of this subpart is governed by § 220.3; this subpart, however, does not affect the use of working wireless communications pursuant to...

  16. 49 CFR 220.301 - Purpose and application.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ..., DEPARTMENT OF TRANSPORTATION RAILROAD COMMUNICATIONS Electronic Devices § 220.301 Purpose and application. (a... or cellular phones) and laptop computers. (b) The applicability of this subpart is governed by § 220.3; this subpart, however, does not affect the use of working wireless communications pursuant to...

  17. 49 CFR 220.301 - Purpose and application.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., DEPARTMENT OF TRANSPORTATION RAILROAD COMMUNICATIONS Electronic Devices § 220.301 Purpose and application. (a... or cellular phones) and laptop computers. (b) The applicability of this subpart is governed by § 220.3; this subpart, however, does not affect the use of working wireless communications pursuant to...

  18. The Vertebrate Brain, Evidence of Its Modular Organization and Operating System: Insights into the Brain's Basic Units of Structure, Function, and Operation and How They Influence Neuronal Signaling and Behavior

    PubMed Central

    Baslow, Morris H.

    2011-01-01

    The human brain is a complex organ made up of neurons and several other cell types, and whose role is processing information for use in eliciting behaviors. However, the composition of its repeating cellular units for both structure and function are unresolved. Based on recent descriptions of the brain's physiological “operating system”, a function of the tri-cellular metabolism of N-acetylaspartate (NAA) and N-acetylaspartylglutamate (NAAG) for supply of energy, and on the nature of “neuronal words and languages” for intercellular communication, insights into the brain's modular structural and functional units have been gained. In this article, it is proposed that the basic structural unit in brain is defined by its physiological operating system, and that it consists of a single neuron, and one or more astrocytes, oligodendrocytes, and vascular system endothelial cells. It is also proposed that the basic functional unit in the brain is defined by how neurons communicate, and consists of two neurons and their interconnecting dendritic–synaptic–dendritic field. Since a functional unit is composed of two neurons, it requires two structural units to form a functional unit. Thus, the brain can be envisioned as being made up of the three-dimensional stacking and intertwining of myriad structural units which results not only in its gross structure, but also in producing a uniform distribution of binary functional units. Since the physiological NAA–NAAG operating system for supply of energy is repeated in every structural unit, it is positioned to control global brain function. PMID:21720525

  19. 76 FR 23923 - Hazardous Materials: Restricting the Use of Cellular Phones by Drivers of Commercial Motor...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-29

    ... associated with the use of cellular (mobile) phones and electronic devices while operating a commercial motor... mobile communication device that falls under or uses any commercial mobile radio service, as defined in... restricting the use of mobile telephones and other distracting electronic devices by railroad operating...

  20. Barriers to Real-Time Medical Direction via Cellular Communication for Prehospital Emergency Care Providers in Gujarat, India.

    PubMed

    Lindquist, Benjamin; Strehlow, Matthew C; Rao, G V Ramana; Newberry, Jennifer A

    2016-07-08

    Many low- and middle-income countries depend on emergency medical technicians (EMTs), nurses, midwives, and layperson community health workers with limited training to provide a majority of emergency medical, trauma, and obstetric care in the prehospital setting. To improve timely patient care and expand provider scope of practice, nations leverage cellular phones and call centers for real-time online medical direction. However, there exist several barriers to adequate communication that impact the provision of emergency care. We sought to identify obstacles in the cellular communication process among GVK Emergency Management and Research Institute (GVK EMRI) EMTs in Gujarat, India. A convenience sample of practicing EMTs in Gujarat, India were surveyed regarding the barriers to call initiation and completion. 108 EMTs completed the survey. Overall, ninety-seven (89.8%) EMTs responded that the most common reason they did not initiate a call with the call center physician was insufficient time. Forty-six (42%) EMTs reported that they were unable to call the physician one or more times during a typical workweek (approximately 5-6 twelve-hour shifts/week) due to their hands being occupied performing direct patient care. Fifty-eight (54%) EMTs reported that they were unable to reach the call center physician, despite attempts, at least once a week. This study identified multiple barriers to communication, including insufficient time to call for advice and inability to reach call center physicians. Identification of simple interventions and best practices may improve communication and ensure timely and appropriate prehospital care.

  1. Wireless data communication alternatives for small public safety agencies: how one community cost-effectively solved its expanding field data requirements

    NASA Astrophysics Data System (ADS)

    Canning, Ryan M.; Lefebvre, Eric

    2005-06-01

    A growing number of Public Safety agencies have begun leveraging wireless data communication technology to improve tactical response capabilities as well as overall productivity. For years police departments subscribed to CDPD (Cellular Digital Packet Data) services to provide officers with basic dispatch data and criminal database access. Now as cellular carriers have deactivated CDPD and shifted to 2.5G and 3G data services such as 1xRTT, GPRS and EDGE, police departments are scrambling to fill the void. Not surprisingly, the extraordinary investments cellular carriers made to upgrade their infrastructures have been transferred to the customer, with monthly fees running as high as $80 a month per user. It's no wonder public safety agencies have been reluctant to adopt these services. Lost in the fray are those smaller police departments which account for nearly 90% of the nation's total. This group has increasingly sought out alternative data communication solutions that are not predicated on budget-busting monthly access fees. One such example is the Marco Island Police Department (MIPD) in Southwestern Florida that received a Federal grant to augment its existing voice communications with data. After evaluating several different technologies and vendors, MIPD chose a 900 MHz ad hoc mesh network solution based on its ability to provide reliable, high-speed and secure IP-based data communications over extensive distances. This paper will discuss technical details of Marco Island's mobile mesh network implementation; including: coverage area with 900 MHz spread spectrum radios, strategic repeater tower placement, interference, throughput performance, and the necessity for application-persistence software.

  2. Life is determined by its environment

    NASA Astrophysics Data System (ADS)

    Torday, John S.; Miller, William B.

    2016-10-01

    A well-developed theory of evolutionary biology requires understanding of the origins of life on Earth. However, the initial conditions (ontology) and causal (epistemology) bases on which physiology proceeded have more recently been called into question, given the teleologic nature of Darwinian evolutionary thinking. When evolutionary development is focused on cellular communication, a distinctly different perspective unfolds. The cellular communicative-molecular approach affords a logical progression for the evolutionary narrative based on the basic physiologic properties of the cell. Critical to this appraisal is recognition of the cell as a fundamental reiterative unit of reciprocating communication that receives information from and reacts to epiphenomena to solve problems. Following the course of vertebrate physiology from its unicellular origins instead of its overt phenotypic appearances and functional associations provides a robust, predictive picture for the means by which complex physiology evolved from unicellular organisms. With this foreknowledge of physiologic principles, we can determine the fundamentals of Physiology based on cellular first principles using a logical, predictable method. Thus, evolutionary creativity on our planet can be viewed as a paradoxical product of boundary conditions that permit homeostatic moments of varying length and amplitude that can productively absorb a variety of epigenetic impacts to meet environmental challenges.

  3. Life is determined by its environment

    PubMed Central

    Torday, John S.; Miller, William B.

    2016-01-01

    A well-developed theory of evolutionary biology requires understanding of the origins of life on Earth. However, the initial conditions (ontology) and causal (epistemology) bases on which physiology proceeded have more recently been called into question, given the teleologic nature of Darwinian evolutionary thinking. When evolutionary development is focused on cellular communication, a distinctly different perspective unfolds. The cellular communicative-molecular approach affords a logical progression for the evolutionary narrative based on the basic physiologic properties of the cell. Critical to this appraisal is recognition of the cell as a fundamental reiterative unit of reciprocating communication that receives information from and reacts to epiphenomena to solve problems. Following the course of vertebrate physiology from its unicellular origins instead of its overt phenotypic appearances and functional associations provides a robust, predictive picture for the means by which complex physiology evolved from unicellular organisms. With this foreknowledge of physiologic principles, we can determine the fundamentals of Physiology based on cellular first principles using a logical, predictable method. Thus, evolutionary creativity on our planet can be viewed as a paradoxical product of boundary conditions that permit homeostatic moments of varying length and amplitude that can productively absorb a variety of epigenetic impacts to meet environmental challenges. PMID:27708547

  4. Characterization of RF front-ends by long-tail pulse response

    NASA Astrophysics Data System (ADS)

    Mazzaro, Gregory J.; Ranney, Kenneth I.

    2010-04-01

    The recognition of unauthorized communications devices at the entry-point of a secure location is one way to guard against the compromise of sensitive information by wireless transmission. Such recognition may be achieved by backscatter x-ray and millimeter-wave imaging; however, implementation of these systems is expensive, and the ability to image the contours of the human body has raised privacy concerns. In this paper, we present a cheaper and less-invasive radio-frequency (RF) alternative for recognizing wireless communications devices. Characterization of the device-under-test (DUT) is accomplished using a stepped-frequency radar waveform. Single-frequency pulses excite resonance in the device's RF front-end. Microsecond periods of zero-signal are placed between each frequency transition to listen for the resonance. The stepped-frequency transmission is swept through known communications bands. Reception of a long-tail decay response between active pulses indicates the presence of a narrowband filter and implies the presence of a front-end circuit. The frequency of the received resonance identifies its communications band. In this work, cellular-band and handheld-radio filters are characterized.

  5. Engineering Cellular Metabolism.

    PubMed

    Nielsen, Jens; Keasling, Jay D

    2016-03-10

    Metabolic engineering is the science of rewiring the metabolism of cells to enhance production of native metabolites or to endow cells with the ability to produce new products. The potential applications of such efforts are wide ranging, including the generation of fuels, chemicals, foods, feeds, and pharmaceuticals. However, making cells into efficient factories is challenging because cells have evolved robust metabolic networks with hard-wired, tightly regulated lines of communication between molecular pathways that resist efforts to divert resources. Here, we will review the current status and challenges of metabolic engineering and will discuss how new technologies can enable metabolic engineering to be scaled up to the industrial level, either by cutting off the lines of control for endogenous metabolism or by infiltrating the system with disruptive, heterologous pathways that overcome cellular regulation. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. Engineering Lipid Bilayer Membranes for Protein Studies

    PubMed Central

    Khan, Muhammad Shuja; Dosoky, Noura Sayed; Williams, John Dalton

    2013-01-01

    Lipid membranes regulate the flow of nutrients and communication signaling between cells and protect the sub-cellular structures. Recent attempts to fabricate artificial systems using nanostructures that mimic the physiological properties of natural lipid bilayer membranes (LBM) fused with transmembrane proteins have helped demonstrate the importance of temperature, pH, ionic strength, adsorption behavior, conformational reorientation and surface density in cellular membranes which all affect the incorporation of proteins on solid surfaces. Much of this work is performed on artificial templates made of polymer sponges or porous materials based on alumina, mica, and porous silicon (PSi) surfaces. For example, porous silicon materials have high biocompatibility, biodegradability, and photoluminescence, which allow them to be used both as a support structure for lipid bilayers or a template to measure the electrochemical functionality of living cells grown over the surface as in vivo. The variety of these media, coupled with the complex physiological conditions present in living systems, warrant a summary and prospectus detailing which artificial systems provide the most promise for different biological conditions. This study summarizes the use of electrochemical impedance spectroscopy (EIS) data on artificial biological membranes that are closely matched with previously published biological systems using both black lipid membrane and patch clamp techniques. PMID:24185908

  7. EHF (28/19 GHz) personal communications satellite terminal development

    NASA Technical Reports Server (NTRS)

    Pike, Corey

    1991-01-01

    The concept of communicating on a personal basis using a small terminal has been investigated globally from many different applications and technology perspectives. Applications range from terrestrial handheld communicators for paging, cellular, zone voice/data networks, etc., to satellite terminals of pocket dimensions for voice/low speed data or similar terminals using larger antennas for VSAT, news gathering (30 cm), and video (1.2 m). A brief status of some developments in the satellite personal communications at CRC will be presented.

  8. Rapid deployable global sensing hazard alert system

    DOEpatents

    Cordaro, Joseph V; Tibrea, Steven L; Shull, Davis J; Coleman, Jerry T; Shuler, James M

    2015-04-28

    A rapid deployable global sensing hazard alert system and associated methods of operation are provided. An exemplary system includes a central command, a wireless backhaul network, and a remote monitoring unit. The remote monitoring unit can include a positioning system configured to determine a position of the remote monitoring unit based on one or more signals received from one or more satellites located in Low Earth Orbit. The wireless backhaul network can provide bidirectional communication capability independent of cellular telecommunication networks and the Internet. An exemplary method includes instructing at least one of a plurality of remote monitoring units to provide an alert based at least in part on a location of a hazard and a plurality of positions respectively associated with the plurality of remote monitoring units.

  9. Conversations between kingdoms: small RNAs.

    PubMed

    Weiberg, Arne; Bellinger, Marschal; Jin, Hailing

    2015-04-01

    Humans, animals, and plants are constantly under attack from pathogens and pests, resulting in severe consequences on global human health and crop production. Small RNA (sRNA)-mediated RNA interference (RNAi) is a conserved regulatory mechanism that is involved in almost all eukaryotic cellular processes, including host immunity and pathogen virulence. Recent evidence supports the significant contribution of sRNAs and RNAi to the communication between hosts and some eukaryotic pathogens, pests, parasites, or symbiotic microorganisms. Mobile silencing signals—most likely sRNAs—are capable of translocating from the host to its interacting organism, and vice versa. In this review, we will provide an overview of sRNA communications between different kingdoms, with a primary focus on the advances in plant-pathogen interaction systems. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Communication Challenges During Incidents of National Significance: A Lesson From Hurricane Katrina

    DTIC Science & Technology

    2006-03-15

    Belle Chasse 17 Sep Qualcomm cellular tower installed at NAS New Orleans23 The timeline referenced above illustrates the very limited communications...active Army do provide unique assets in their responses to such crises . A significant challenge of interoperability between the DoD assets and first

  11. 76 FR 45579 - Request for Notification From Consumer Organizations Interested in Participating in the Selection...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-29

    ... Communication--Knowledgeable in 1-Voting 5/31/12 risk communication, risk management, drug safety, medical..., sociology/ ethics, and other related professions. Cellular Tissue and Gene Therapies--Knowledgeable in 1... physical sciences, sociology/ethics, and other related professions. Vaccines and Related Biological...

  12. Development of a population of cancer cells: Observation and modeling by a Mixed Spatial Evolutionary Games approach.

    PubMed

    Świerniak, Andrzej; Krześlak, Michał; Student, Sebastian; Rzeszowska-Wolny, Joanna

    2016-09-21

    Living cells, like whole living organisms during evolution, communicate with their neighbors, interact with the environment, divide, change their phenotypes, and eventually die. The development of specific ways of communication (through signaling molecules and receptors) allows some cellular subpopulations to survive better, to coordinate their physiological status, and during embryonal development to create tissues and organs or in some conditions to become tumors. Populations of cells cultured in vitro interact similarly, also competing for space and nutrients and stimulating each other to better survive or to die. The results of these intercellular interactions of different types seem to be good examples of biological evolutionary games, and have been the subjects of simulations by the methods of evolutionary game theory where individual cells are treated as players. Here we present examples of intercellular contacts in a population of living human cancer HeLa cells cultured in vitro and propose an evolutionary game theory approach to model the development of such populations. We propose a new technique termed Mixed Spatial Evolutionary Games (MSEG) which are played on multiple lattices corresponding to the possible cellular phenotypes which gives the possibility of simulating and investigating the effects of heterogeneity at the cellular level in addition to the population level. Analyses performed with MSEG suggested different ways in which cellular populations develop in the case of cells communicating directly and through factors released to the environment. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Collective synchronization of self/non-self discrimination in T cell activation, across multiple spatio-temporal scales

    NASA Astrophysics Data System (ADS)

    Altan-Bonnet, Gregoire

    The immune system is a collection of cells whose function is to eradicate pathogenic infections and malignant tumors while protecting healthy tissues. Recent work has delineated key molecular and cellular mechanisms associated with the ability to discriminate self from non-self agents. For example, structural studies have quantified the biophysical characteristics of antigenic molecules (those prone to trigger lymphocyte activation and a subsequent immune response). However, such molecular mechanisms were found to be highly unreliable at the individual cellular level. We will present recent efforts to build experimentally validated computational models of the immune responses at the collective cell level. Such models have become critical to delineate how higher-level integration through nonlinear amplification in signal transduction, dynamic feedback in lymphocyte differentiation and cell-to-cell communication allows the immune system to enforce reliable self/non-self discrimination at the organism level. In particular, we will present recent results demonstrating how T cells tune their antigen discrimination according to cytokine cues, and how competition for cytokine within polyclonal populations of cells shape the repertoire of responding clones. Additionally, we will present recent theoretical and experimental results demonstrating how competition between diffusion and consumption of cytokines determine the range of cell-cell communications within lymphoid organs. Finally, we will discuss how biochemically explicit models, combined with quantitative experimental validation, unravel the relevance of new feedbacks for immune regulations across multiple spatial and temporal scales.

  14. Efficient massively parallel simulation of dynamic channel assignment schemes for wireless cellular communications

    NASA Technical Reports Server (NTRS)

    Greenberg, Albert G.; Lubachevsky, Boris D.; Nicol, David M.; Wright, Paul E.

    1994-01-01

    Fast, efficient parallel algorithms are presented for discrete event simulations of dynamic channel assignment schemes for wireless cellular communication networks. The driving events are call arrivals and departures, in continuous time, to cells geographically distributed across the service area. A dynamic channel assignment scheme decides which call arrivals to accept, and which channels to allocate to the accepted calls, attempting to minimize call blocking while ensuring co-channel interference is tolerably low. Specifically, the scheme ensures that the same channel is used concurrently at different cells only if the pairwise distances between those cells are sufficiently large. Much of the complexity of the system comes from ensuring this separation. The network is modeled as a system of interacting continuous time automata, each corresponding to a cell. To simulate the model, conservative methods are used; i.e., methods in which no errors occur in the course of the simulation and so no rollback or relaxation is needed. Implemented on a 16K processor MasPar MP-1, an elegant and simple technique provides speedups of about 15 times over an optimized serial simulation running on a high speed workstation. A drawback of this technique, typical of conservative methods, is that processor utilization is rather low. To overcome this, new methods were developed that exploit slackness in event dependencies over short intervals of time, thereby raising the utilization to above 50 percent and the speedup over the optimized serial code to about 120 times.

  15. Cell-to-cell communication and cellular environment alter the somatostatin status of delta cells

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

    Kelly, Catriona, E-mail: catriona.kelly@qub.ac.uk; Flatt, Peter R.; McClenaghan, Neville H.

    2010-08-20

    Research highlights: {yields} TGP52 cells display enhanced functionality in pseudoislet form. {yields} Somatostatin content was reduced, but secretion increased in high glucose conditions. {yields} Cellular interactions and environment alter the somatostatin status of TGP52 cells. -- Abstract: Introduction: Somatostatin, released from pancreatic delta cells, is a potent paracrine inhibitor of insulin and glucagon secretion. Islet cellular interactions and glucose homeostasis are essential to maintain normal patterns of insulin secretion. However, the importance of cell-to-cell communication and cellular environment in the regulation of somatostatin release remains unclear. Methods: This study employed the somatostatin-secreting TGP52 cell line maintained in DMEM:F12 (17.5 mMmore » glucose) or DMEM (25 mM glucose) culture media. The effect of pseudoislet formation and culture medium on somatostatin content and release in response to a variety of stimuli was measured by somatostatin EIA. In addition, the effect of pseudoislet formation on cellular viability (MTT and LDH assays) and proliferation (BrdU ELISA) was determined. Results: TGP52 cells readily formed pseudoislets and showed enhanced functionality in three-dimensional form with increased E-cadherin expression irrespective of the culture environment used. However, culture in DMEM decreased cellular somatostatin content (P < 0.01) and increased somatostatin secretion in response to a variety of stimuli including arginine, calcium and PMA (P < 0.001) when compared with cells grown in DMEM:F12. Configuration of TGP52 cells as pseudoislets reduced the proliferative rate and increased cellular cytotoxicity irrespective of culture medium used. Conclusions: Somatostatin secretion is greatly facilitated by cell-to-cell interactions and E-cadherin expression. Cellular environment and extracellular glucose also significantly influence the function of delta cells.« less

  16. Real-Time Cellular Exometabolome Analysis with a Microfluidic-Mass Spectrometry Platform

    PubMed Central

    Marasco, Christina C.; Enders, Jeffrey R.; Seale, Kevin T.; McLean, John A.; Wikswo, John P.

    2015-01-01

    To address the challenges of tracking the multitude of signaling molecules and metabolites that is the basis of biological complexity, we describe a strategy to expand the analytical techniques for dynamic systems biology. Using microfluidics, online desalting, and mass spectrometry technologies, we constructed and validated a platform well suited for sampling the cellular microenvironment with high temporal resolution. Our platform achieves success in: automated cellular stimulation and microenvironment control; reduced non-specific adsorption to polydimethylsiloxane due to surface passivation; real-time online sample collection; near real-time sample preparation for salt removal; and real-time online mass spectrometry. When compared against the benchmark of “in-culture” experiments combined with ultraperformance liquid chromatography-electrospray ionization-ion mobility-mass spectrometry (UPLC-ESI-IM-MS), our platform alleviates the volume challenge issues caused by dilution of autocrine and paracrine signaling and dramatically reduces sample preparation and data collection time, while reducing undesirable external influence from various manual methods of manipulating cells and media (e.g., cell centrifugation). To validate this system biologically, we focused on cellular responses of Jurkat T cells to microenvironmental stimuli. Application of these stimuli, in conjunction with the cell’s metabolic processes, results in changes in consumption of nutrients and secretion of biomolecules (collectively, the exometabolome), which enable communication with other cells or tissues and elimination of waste. Naïve and experienced T-cell metabolism of cocaine is used as an exemplary system to confirm the platform’s capability, highlight its potential for metabolite discovery applications, and explore immunological memory of T-cell drug exposure. Our platform proved capable of detecting metabolomic variations between naïve and experienced Jurkat T cells and highlights the dynamics of the exometabolome over time. Upregulation of the cocaine metabolite, benzoylecgonine, was noted in experienced T cells, indicating potential cellular memory of cocaine exposure. These metabolomics distinctions were absent from the analogous, traditional “in-culture” UPLC-ESI-IM-MS experiment, further demonstrating this platform’s capabilities. PMID:25723555

  17. Live Imaging and Laser Disruption Reveal the Dynamics and Cell-Cell Communication During Torenia fournieri Female Gametophyte Development.

    PubMed

    Susaki, Daichi; Takeuchi, Hidenori; Tsutsui, Hiroki; Kurihara, Daisuke; Higashiyama, Tetsuya

    2015-05-01

    The female gametophytes of many flowering plants contain one egg cell, one central cell, two synergid cells and three antipodal cells with respective morphological characteristics and functions. These cells are formed by cellularization of a multinuclear female gametophyte. However, the dynamics and mechanisms of female gametophyte development remain largely unknown due to the lack of a system to visualize directly and manipulate female gametophytes in living material. Here, we established an in vitro ovule culture system to examine female gametophyte development in Torenia fournieri, a unique plant species with a protruding female gametophyte. The four-nucleate female gametophyte became eight nucleate by the final (third) mitosis and successively cellularized and matured to attract a pollen tube. The duration of final mitosis was 28 ± 6.5 min, and cellularization was completed in 54 ± 20 min after the end of the third mitosis. Fusion of polar nuclei in the central cell occurred in 13.1 ± 1.1 h, and onset of expression of LURE2, a pollen tube attractant gene, was visualized by a green fluorescent protein reporter 10.7 ± 2.3 h after cellularization. Laser disruption analysis demonstrated that the egg and central cells were required for synergid cells to acquire the pollen tube attraction function. Moreover, aberrant nuclear positioning and down-regulation of LURE2 were observed in one of the two synergid cells after disrupting an immature egg cell, suggesting that cell specification was affected. Our system provides insights into the precise dynamics and mechanisms of female gametophyte development in T. fournieri. © The Author 2015. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  18. Bluetooth telemedicine processor for multichannel biomedical signal transmission via mobile cellular networks.

    PubMed

    Rasid, Mohd Fadlee A; Woodward, Bryan

    2005-03-01

    One of the emerging issues in m-Health is how best to exploit the mobile communications technologies that are now almost globally available. The challenge is to produce a system to transmit a patient's biomedical signals directly to a hospital for monitoring or diagnosis, using an unmodified mobile telephone. The paper focuses on the design of a processor, which samples signals from sensors on the patient. It then transmits digital data over a Bluetooth link to a mobile telephone that uses the General Packet Radio Service. The modular design adopted is intended to provide a "future-proofed" system, whose functionality may be upgraded by modifying the software.

  19. The cellular slime mold: eukaryotic model microorganism.

    PubMed

    Urushihara, Hideko

    2009-04-01

    Cellular slime molds are eukaryotic microorganisms in the soil. They feed on bacteria as solitary amoebae but conditionally construct multicellular forms in which cell differentiation takes place. Therefore, they are attractive for the study of fundamental biological phenomena such as phagocytosis, cell division, chemotactic movements, intercellular communication, cell differentiation, and morphogenesis. The most widely used species, Dictyostelium discoideum, is highly amenable to experimental manipulation and can be used with most recent molecular biological techniques. Its genome and cDNA analyses have been completed and well-annotated data are publicly available. A larger number of orthologues of human disease-related genes were found in D. discoideum than in yeast. Moreover, some pathogenic bacteria infect Dictyostelium amoebae. Thus, this microorganism can also offer a good experimental system for biomedical research. The resources of cellular slime molds, standard strains, mutants, and genes are maintained and distributed upon request by the core center of the National BioResource Project (NBRP-nenkin) to support Dictyostelium community users as well as new users interested in new platforms for research and/or phylogenic consideration.

  20. Open-source telemedicine platform for wireless medical video communication.

    PubMed

    Panayides, A; Eleftheriou, I; Pantziaris, M

    2013-01-01

    An m-health system for real-time wireless communication of medical video based on open-source software is presented. The objective is to deliver a low-cost telemedicine platform which will allow for reliable remote diagnosis m-health applications such as emergency incidents, mass population screening, and medical education purposes. The performance of the proposed system is demonstrated using five atherosclerotic plaque ultrasound videos. The videos are encoded at the clinically acquired resolution, in addition to lower, QCIF, and CIF resolutions, at different bitrates, and four different encoding structures. Commercially available wireless local area network (WLAN) and 3.5G high-speed packet access (HSPA) wireless channels are used to validate the developed platform. Objective video quality assessment is based on PSNR ratings, following calibration using the variable frame delay (VFD) algorithm that removes temporal mismatch between original and received videos. Clinical evaluation is based on atherosclerotic plaque ultrasound video assessment protocol. Experimental results show that adequate diagnostic quality wireless medical video communications are realized using the designed telemedicine platform. HSPA cellular networks provide for ultrasound video transmission at the acquired resolution, while VFD algorithm utilization bridges objective and subjective ratings.

  1. 802.11 Wireless Infrastructure To Enhance Medical Response to Disasters

    PubMed Central

    Arisoylu, Mustafa; Mishra, Rajesh; Rao, Ramesh; Lenert, Leslie A.

    2005-01-01

    802.11 (WiFi) is a well established network communications protocol that has wide applicability in civil infrastructure. This paper describes research that explores the design of 802.11 networks enhanced to support data communications in disaster environments. The focus of these efforts is to create network infrastructure to support operations by Metropolitan Medical Response System (MMRS) units and Federally-sponsored regional teams that respond to mass casualty events caused by a terrorist attack with chemical, biological, nuclear or radiological weapons or by a hazardous materials spill. In this paper, we describe an advanced WiFi-based network architecture designed to meet the needs of MMRS operations. This architecture combines a Wireless Distribution Systems for peer-to-peer multihop connectivity between access points with flexible and shared access to multiple cellular backhauls for robust connectivity to the Internet. The architecture offers a high bandwidth data communications infrastructure that can penetrate into buildings and structures while also supporting commercial off-the-shelf end-user equipment such as PDAs. It is self-configuring and is self-healing in the event of a loss of a portion of the infrastructure. Testing of prototype units is ongoing. PMID:16778990

  2. Open-Source Telemedicine Platform for Wireless Medical Video Communication

    PubMed Central

    Panayides, A.; Eleftheriou, I.; Pantziaris, M.

    2013-01-01

    An m-health system for real-time wireless communication of medical video based on open-source software is presented. The objective is to deliver a low-cost telemedicine platform which will allow for reliable remote diagnosis m-health applications such as emergency incidents, mass population screening, and medical education purposes. The performance of the proposed system is demonstrated using five atherosclerotic plaque ultrasound videos. The videos are encoded at the clinically acquired resolution, in addition to lower, QCIF, and CIF resolutions, at different bitrates, and four different encoding structures. Commercially available wireless local area network (WLAN) and 3.5G high-speed packet access (HSPA) wireless channels are used to validate the developed platform. Objective video quality assessment is based on PSNR ratings, following calibration using the variable frame delay (VFD) algorithm that removes temporal mismatch between original and received videos. Clinical evaluation is based on atherosclerotic plaque ultrasound video assessment protocol. Experimental results show that adequate diagnostic quality wireless medical video communications are realized using the designed telemedicine platform. HSPA cellular networks provide for ultrasound video transmission at the acquired resolution, while VFD algorithm utilization bridges objective and subjective ratings. PMID:23573082

  3. Short-Block Protograph-Based LDPC Codes

    NASA Technical Reports Server (NTRS)

    Divsalar, Dariush; Dolinar, Samuel; Jones, Christopher

    2010-01-01

    Short-block low-density parity-check (LDPC) codes of a special type are intended to be especially well suited for potential applications that include transmission of command and control data, cellular telephony, data communications in wireless local area networks, and satellite data communications. [In general, LDPC codes belong to a class of error-correcting codes suitable for use in a variety of wireless data-communication systems that include noisy channels.] The codes of the present special type exhibit low error floors, low bit and frame error rates, and low latency (in comparison with related prior codes). These codes also achieve low maximum rate of undetected errors over all signal-to-noise ratios, without requiring the use of cyclic redundancy checks, which would significantly increase the overhead for short blocks. These codes have protograph representations; this is advantageous in that, for reasons that exceed the scope of this article, the applicability of protograph representations makes it possible to design highspeed iterative decoders that utilize belief- propagation algorithms.

  4. The Clear Creek Envirohydrologic Observatory: From Vision Toward Reality

    NASA Astrophysics Data System (ADS)

    Just, C.; Muste, M.; Kruger, A.

    2007-12-01

    As the vision of a fully-functional Clear Creek Envirohydrologic Observatory comes closer to reality, the opportunities for significant watershed science advances in the near future become more apparent. As a starting point to approaching this vision, we focused on creating a working example of cyberinfrastructure in the hydrologic and environmental sciences. The system will integrate a broad range of technologies and ideas: wired and wireless sensors, low power wireless communication, embedded microcontrollers, commodity cellular networks, the internet, unattended quality assurance, metadata, relational databases, machine-to-machine communication, interfaces to hydrologic and environmental models, feedback, and external inputs. Hardware: An accomplishment to date is "in-house" developed sensor networking electronics to compliment commercially available communications. The first of these networkable sensors are dielectric soil moisture probes that are arrayed and equipped with wireless connectivity for communications. Commercially available data logging and telemetry-enabled systems deployed at the Clear Creek testbed include a Campbell Scientific CR1000 datalogger, a Redwing 100 cellular modem, a YA Series yagi antenna, a NP12 rechargeable battery, and a BP SX20U solar panel. This networking equipment has been coupled with Hach DS5X water quality sondes, DTS-12 turbidity probes and MicroLAB nutrient analyzers. Software: Our existing data model is an Arc Hydro-based geodatabase customized with applications for extraction and population of the database with third party data. The following third party data are acquired automatically and in real time into the Arc Hydro customized database: 1) geophysical data: 10m DEM and soil grids, soils; 2) land use/land cover data; and 3) eco-hydrological: radar-based rainfall estimates, stream gage, streamlines, and water quality data. A new processing software for data analysis of Acoustic Doppler Current Profilers (ADCP) measurements has been finalized. The software package provides mean flow field and turbulence characteristics obtained by operating the ADCP at fixed points or using the moving-boat approach. Current Work: The current development work is focused on extracting and populating the Clear Creek database with in-situ measurements acquired and transmitted in real time with sensors deployed in the Clear Creek watershed.

  5. Biomaterials-based electronics: polymers and interfaces for biology and medicine.

    PubMed

    Muskovich, Meredith; Bettinger, Christopher J

    2012-05-01

    Advanced polymeric biomaterials continue to serve as a cornerstone for new medical technologies and therapies. The vast majority of these materials, both natural and synthetic, interact with biological matter in the absence of direct electronic communication. However, biological systems have evolved to synthesize and utilize naturally-derived materials for the generation and modulation of electrical potentials, voltage gradients, and ion flows. Bioelectric phenomena can be translated into potent signaling cues for intra- and inter-cellular communication. These cues can serve as a gateway to link synthetic devices with biological systems. This progress report will provide an update on advances in the application of electronically active biomaterials for use in organic electronics and bio-interfaces. Specific focus will be granted to covering technologies where natural and synthetic biological materials serve as integral components such as thin film electronics, in vitro cell culture models, and implantable medical devices. Future perspectives and emerging challenges will also be highlighted. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Theoretical aspects and modelling of cellular decision making, cell killing and information-processing in photodynamic therapy of cancer.

    PubMed

    Gkigkitzis, Ioannis

    2013-01-01

    The aim of this report is to provide a mathematical model of the mechanism for making binary fate decisions about cell death or survival, during and after Photodynamic Therapy (PDT) treatment, and to supply the logical design for this decision mechanism as an application of rate distortion theory to the biochemical processing of information by the physical system of a cell. Based on system biology models of the molecular interactions involved in the PDT processes previously established, and regarding a cellular decision-making system as a noisy communication channel, we use rate distortion theory to design a time dependent Blahut-Arimoto algorithm where the input is a stimulus vector composed of the time dependent concentrations of three PDT related cell death signaling molecules and the output is a cell fate decision. The molecular concentrations are determined by a group of rate equations. The basic steps are: initialize the probability of the cell fate decision, compute the conditional probability distribution that minimizes the mutual information between input and output, compute the cell probability of cell fate decision that minimizes the mutual information and repeat the last two steps until the probabilities converge. Advance to the next discrete time point and repeat the process. Based on the model from communication theory described in this work, and assuming that the activation of the death signal processing occurs when any of the molecular stimulants increases higher than a predefined threshold (50% of the maximum concentrations), for 1800s of treatment, the cell undergoes necrosis within the first 30 minutes with probability range 90.0%-99.99% and in the case of repair/survival, it goes through apoptosis within 3-4 hours with probability range 90.00%-99.00%. Although, there is no experimental validation of the model at this moment, it reproduces some patterns of survival ratios of predicted experimental data. Analytical modeling based on cell death signaling molecules has been shown to be an independent and useful tool for prediction of cell surviving response to PDT. The model can be adjusted to provide important insights for cellular response to other treatments such as hyperthermia, and diseases such as neurodegeneration.

  7. A Reversible DNA Logic Gate Platform Operated by One- and Two-Photon Excitations.

    PubMed

    Tam, Dick Yan; Dai, Ziwen; Chan, Miu Shan; Liu, Ling Sum; Cheung, Man Ching; Bolze, Frederic; Tin, Chung; Lo, Pik Kwan

    2016-01-04

    We demonstrate the use of two different wavelength ranges of excitation light as inputs to remotely trigger the responses of the self-assembled DNA devices (D-OR). As an important feature of this device, the dependence of the readout fluorescent signals on the two external inputs, UV excitation for 1 min and/or near infrared irradiation (NIR) at 800 nm fs laser pulses, can mimic function of signal communication in OR logic gates. Their operations could be reset easily to its initial state. Furthermore, these DNA devices exhibit efficient cellular uptake, low cytotoxicity, and high bio-stability in different cell lines. They are considered as the first example of a photo-responsive DNA logic gate system, as well as a biocompatible, multi-wavelength excited system in response to UV and NIR. This is an important step to explore the concept of photo-responsive DNA-based systems as versatile tools in DNA computing, display devices, optical communication, and biology. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. SUPL support for mobile devices

    NASA Astrophysics Data System (ADS)

    Narisetty, Jayanthi; Soghoyan, Arpine; Sundaramurthy, Mohanapriya; Akopian, David

    2012-02-01

    Conventional Global Positioning System (GPS) receivers operate well in open-sky environments. But their performance degrades in urban canyons, indoors and underground due to multipath, foliage, dissipation, etc. To overcome such situations, several enhancements have been suggested such as Assisted GPS (A-GPS). Using this approach, orbital parameters including ephemeris and almanac along with reference time and coarse location information are provided to GPS receivers to assist in acquisition of weak signals. To test A-GPS enabled receivers high-end simulators are used, which are not affordable by many academic institutions. This paper presents an economical A-GPS supplement for inexpensive simulators which operates on application layer. Particularly proposed solution is integrated with National Instruments' (NI) GPS Simulation Toolkit and implemented using NI's Labview environment. This A-GPS support works for J2ME and Android platforms. The communication between the simulator and the receiver is in accordance with the Secure User Plane Location (SUPL) protocol encapsulated with Radio Resource Location Protocol (RRLP) applies to Global System for Mobile Communications (GSM) and Universal Mobile Telecommunications System (UMTS) cellular networks.

  9. Recent advances in near-surface moisture monitoring using commercial microwave links in Tel-Aviv University

    NASA Astrophysics Data System (ADS)

    Alpert, Pinhas; David, Noam; Messer, Hagit

    2015-04-01

    The propagation of electromagnetic radiation in the lower atmosphere, at centimeter wavelengths, is impaired by atmospheric conditions. Absorption and scattering of the radiation, at frequencies of tens of GHz, are directly related to the atmospheric phenomena, primarily precipitation, oxygen, mist, fog and water vapor. As was recently shown, wireless communication networks supply high resolution precipitation measurements at ground level while often being situated in flood prone areas, covering large parts of these hazardous regions. On the other hand, at present, there are no satisfactory real time flash flood warning facilities found to cope well with this phenomenon. I will exemplify the flash flood warning potential of the commercial wireless communication system for two different semi-arid region cases when floods occurred in the Judean desert and in the northern Negev in Israel. In addition, I will review our recent improvements in monitoring rainfall as well as other-than-rain phenomena like, atmospheric moisture. Special focus on fog monitoring potential will be highlighted. References: N. David, O. Sendik, H. Messer and P. Alpert, "Cellular network infrastructure- the future of fog monitoring?", BAMS, (in press, 2015). N. David, P. Alpert and H. Messer, "The potential of cellular network infrastructures for sudden rainfall monitoring in dry climate regions", Atmospheric Research, 131, 13-21, 2013.

  10. 21 CFR 1271.440 - Orders of retention, recall, destruction, and cessation of manufacturing.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... FOOD AND DRUG ADMINISTRATION HUMAN CELLS, TISSUES, AND CELLULAR AND TISSUE-BASED PRODUCTS Inspection... protections against risks of communicable disease transmission; or the HCT/P is infected or contaminated so as... communicable disease transmission, the Food and Drug Administration (FDA) may take one or more of the following...

  11. Microcomputer-assisted transmission of disaster data by cellular telephone.

    PubMed

    Wigder, H N; Fligner, D J; Rivers, D; Hotch, D

    1989-01-01

    Voice communication of information during disasters is often inadequate. In particular, simultaneous transmission by multiple callers on the same frequency can result in blocked transmissions and miscommunications. In contrast, nonvoice transmission of data requires less time than does voice communication of the same data, and may be more accurate. We conducted a pilot study to test the feasibility of a microcomputer assisted communication (MAC) network linking the disaster scene and the command hospital. The radio chosen to transmit data from the field disaster site to the command hospital was a cellular telephone connected to the microcomputer by modem. Typed communications between the microcomputer operators enabled dialogue between the disaster site and the hospitals. A computer program using commercially available software (Symphony by Lotus, Inc.) was written to allow for data entry, data transmission, and reports. Patient data, including age, sex, severity of injury, identification number, major injuries, and hospital destination were successfully transmitted from the disaster site command post to the command hospital. This pilot test demonstrated the potential applicability of MAC for facilitating transmission of patient data during a disaster.

  12. Future communications satellite applications

    NASA Technical Reports Server (NTRS)

    Bagwell, James W.

    1992-01-01

    The point of view of the research is made through the use of viewgraphs. It is suggested that future communications satellite applications will be made through switched point to point narrowband communications. Some characteristics of which are as follows: small/low cost terminals; single hop communications; voice compatible; full mesh networking; ISDN compatible; and possible limited use of full motion video. Some target applications are as follows: voice/data networks between plants and offices in a corporation; data base networking for commercial and science users; and cellular radio internodal voice/data networking.

  13. [Sarcopenia: toward its clinical utilisation].

    PubMed

    Bijlsma, Astrid Y; Meskers, Carel G M; Westendorp, Rudi G J; Maier, Andrea B

    2013-01-01

    Sarcopenia is a term that was introduced to describe 'low muscle mass'. There is no consensus definition for sarcopenia; a variety of criteria are being used to establish the diagnosis of 'sarcopenia'. Depending on the criteria used, the prevalence of sarcopenia in elderly varies from 7% to over 50%. The presence of sarcopenia often remains unrecognized when the loss of muscle mass is replaced by fat and connective tissue; body weight thus remains stable or even increases. Sarcopenia can be detected by measuring muscle mass with dual-energy X-ray absorptiometry (DEXA) or bioimpedance analysis (BIA). Besides the generation of strength, muscle tissue is an important internal organ involved in protein storage, glucose regulation, hormonal homeostasis and cellular communication. Systemic, cellular, neuromechanical factors and lifestyle are linked to the pathophysiology of sarcopenia. Sarcopenia is associated with higher mortality, dependency in activities of daily living, toxicity of chemotherapy, and disturbed glucose regulation.

  14. Riding the Waves: How Our Cells Send Signals | Center for Cancer Research

    Cancer.gov

    The ability of cells to perceive and respond to their environment is critical in order to maintain basic cellular functions such as development, tissue repair, and response to stress. This process happens through a complex system of communication, called cell signaling, which governs basic cellular activities and coordinates cell actions. Errors in cell signaling have been linked to numerous diseases, including cancer. NF-κB is a protein complex that plays a critical role in many cell signaling pathways by controlling gene activation. It is widely used by cells to regulate cell growth and survival and helps to protect the cell from conditions that would otherwise cause it to die. Many tumor cells have mutations in genes that cause NF-κB to become overactive. Blocking NF-κB could cause tumor cells to stop growing, die, or become more sensitive to therapeutics.

  15. Attention: oscillations and neuropharmacology.

    PubMed

    Deco, Gustavo; Thiele, Alexander

    2009-08-01

    Attention is a rich psychological and neurobiological construct that influences almost all aspects of cognitive behaviour. It enables enhanced processing of behaviourally relevant stimuli at the expense of irrelevant stimuli. At the cellular level, rhythmic synchronization at local and long-range spatial scales complements the attention-induced firing rate changes of neurons. The former is hypothesized to enable efficient communication between neuronal ensembles tuned to spatial and featural aspects of the attended stimulus. Recent modelling studies suggest that the rhythmic synchronization in the gamma range may be mediated by a fine balance between N-methyl-D-aspartate and alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate postsynaptic currents, whereas other studies have highlighted the possible contribution of the neuromodulator acetylcholine. This review summarizes some recent modelling and experimental studies investigating mechanisms of attention in sensory areas and discusses possibilities of how glutamatergic and cholinergic systems could contribute to increased processing abilities at the cellular and network level during states of top-down attention.

  16. Biomedical sensing analyzer (BSA) for mobile-health (mHealth)-LTE.

    PubMed

    Adibi, Sasan

    2014-01-01

    The rapid expansion of mobile-based systems, the capabilities of smartphone devices, as well as the radio access and cellular network technologies are the wind beneath the wing of mobile health (mHealth). In this paper, the concept of biomedical sensing analyzer (BSA) is presented, which is a novel framework, devised for sensor-based mHealth applications. The BSA is capable of formulating the Quality of Service (QoS) measurements in an end-to-end sense, covering the entire communication path (wearable sensors, link-technology, smartphone, cell-towers, mobile-cloud, and the end-users). The characterization and formulation of BSA depend on a number of factors, including the deployment of application-specific biomedical sensors, generic link-technologies, collection, aggregation, and prioritization of mHealth data, cellular network based on the Long-Term Evolution (LTE) access technology, and extensive multidimensional delay analyses. The results are studied and analyzed in a LabView 8.5 programming environment.

  17. Digital Material Assembly by Passive Means and Modular Isotropic Lattice Extruder System

    NASA Technical Reports Server (NTRS)

    Gershenfeld, Neil (Inventor); Carney, Matthew Eli (Inventor); Jenett, Benjamin (Inventor)

    2017-01-01

    A set of machines and related systems build structures by the additive assembly of discrete parts. These digital material assemblies constrain the constituent parts to a discrete set of possible positions and orientations. In doing so, the structures exhibit many of the properties inherent in digital communication such as error correction, fault tolerance and allow the assembly of precise structures with comparatively imprecise tools. Assembly of discrete cellular lattices by a Modular Isotropic Lattice Extruder System (MILES) is implemented by pulling strings of lattice elements through a forming die that enforces geometry constraints that lock the elements into a rigid structure that can then be pushed against and extruded out of the die as an assembled, loadbearing structure.

  18. Cascading Policies Provide Fault Tolerance for Pervasive Clinical Communications.

    PubMed

    Williams, Rose; Jalan, Srikant; Stern, Edie; Lussier, Yves A

    2005-03-21

    We implemented an end-to-end notification system that pushed urgent clinical laboratory results to Blackberry 7510 devices over the Nextel cellular network. We designed our system to use user roles and notification policies to abstract and execute clinical notification procedures. We anticipated some problems with dropped and non-delivered messages when the device was out-of-network, however, we did not expect the same problems in other situations like device reconnection to the network. We addressed these problems by creating cascading "fault tolerance" policies to drive notification escalation when messages timed-out or delivery failed. This paper describes our experience in providing an adaptable, fault tolerant pervasive notification system for delivering secure, critical, time-sensitive patient laboratory results.

  19. Medical Data Transmission Using Cell Phone Networks

    NASA Astrophysics Data System (ADS)

    Voos, J.; Centeno, C.; Riva, G.; Zerbini, C.; Gonzalez, E.

    2011-12-01

    A big challenge in telemedicine systems is related to have the technical requirements needed for a successful implementation in remote locations where the available hardware and communication infrastructure is not adequate for a good medical data transmission. Despite of the wide standards availability, methodologies, applications and systems integration facilities in telemedicine, in many cases the implementation requirements are not achievable to allow the system execution in remote areas of our country. Therefore, this paper presents an alternative for the messages transmission related to medical studies using the cellular network and the standard HL7 V3 [1] for data modeling. The messages are transmitted to a web server and stored in a centralized database which allows data sharing with other specialists.

  20. System-Level Performance of Antenna Arrays in CDMA-Based Cellular Mobile Radio Systems

    NASA Astrophysics Data System (ADS)

    Czylwik, Andreas; Dekorsy, Armin

    2004-12-01

    Smart antennas exploit the inherent spatial diversity of the mobile radio channel, provide an antenna gain, and also enable spatial interference suppression leading to reduced intracell as well as intercell interference. Especially, for the downlink of future CDMA-based mobile communications systems, transmit beamforming is seen as a well-promising smart antenna technique. The main objective of this paper is to study the performance of diverse antenna array topologies when applied for transmit beamforming in the downlink of CDMA-based networks. In this paper, we focus on uniform linear array (ULA) and uniform circular array (UCA) topologies. For the ULA, we consider three-sector base stations with one linear array per sector. While recent research on downlink beamforming is often restricted to one single cell, this study takes into account the important impact of intercell interference on the performance by evaluating complete networks. Especially, from the operator perspective, system capacity and system coverage are very essential parameters of a cellular system so that there is a clear necessity of intensive system level investigations. Apart from delivering assessments on the performance of the diverse antenna array topologies, in the paper also different antenna array parameters, such as element spacing and beamwidth of the sector antennas, are optimized. Although we focus on the network level, fast channel fluctuations are taken into account by including them analytically into the signal-to-interference calculation.

  1. Gap junctions in cells of the immune system: structure, regulation and possible functional roles.

    PubMed

    Sáez, J C; Brañes, M C; Corvalán, L A; Eugenín, E A; González, H; Martínez, A D; Palisson, F

    2000-04-01

    Gap junction channels are sites of cytoplasmic communication between contacting cells. In vertebrates, they consist of protein subunits denoted connexins (Cxs) which are encoded by a gene family. According to their Cx composition, gap junction channels show different gating and permeability properties that define which ions and small molecules permeate them. Differences in Cx primary sequences suggest that channels composed of different Cxs are regulated differentially by intracellular pathways under specific physiological conditions. Functional roles of gap junction channels could be defined by the relative importance of permeant substances, resulting in coordination of electrical and/or metabolic cellular responses. Cells of the native and specific immune systems establish transient homo- and heterocellular contacts at various steps of the immune response. Morphological and functional studies reported during the last three decades have revealed that many intercellular contacts between cells in the immune response present gap junctions or "gap junction-like" structures. Partial characterization of the molecular composition of some of these plasma membrane structures and regulatory mechanisms that control them have been published recently. Studies designed to elucidate their physiological roles suggest that they might permit coordination of cellular events which favor the effective and timely response of the immune system.

  2. Specific targeting of proteins to outer envelope membranes of endosymbiotic organelles, chloroplasts, and mitochondria

    PubMed Central

    Lee, Junho; Kim, Dae Heon; Hwang, Inhwan

    2014-01-01

    Chloroplasts and mitochondria are endosymbiotic organelles thought to be derived from endosymbiotic bacteria. In present-day eukaryotic cells, these two organelles play pivotal roles in photosynthesis and ATP production. In addition to these major activities, numerous reactions, and cellular processes that are crucial for normal cellular functions occur in chloroplasts and mitochondria. To function properly, these organelles constantly communicate with the surrounding cellular compartments. This communication includes the import of proteins, the exchange of metabolites and ions, and interactions with other organelles, all of which heavily depend on membrane proteins localized to the outer envelope membranes. Therefore, correct and efficient targeting of these membrane proteins, which are encoded by the nuclear genome and translated in the cytosol, is critically important for organellar function. In this review, we summarize the current knowledge of the mechanisms of protein targeting to the outer membranes of mitochondria and chloroplasts in two different directions, as well as targeting signals and cytosolic factors. PMID:24808904

  3. Four domains: The fundamental unicell and Post-Darwinian Cognition-Based Evolution.

    PubMed

    Miller, William B; Torday, John S

    2018-04-13

    Contemporary research supports the viewpoint that self-referential cognition is the proper definition of life. From that initiating platform, a cohesive alternative evolutionary narrative distinct from standard Neodarwinism can be presented. Cognition-Based Evolution contends that biological variation is a product of a self-reinforcing information cycle that derives from self-referential attachment to biological information space-time with its attendant ambiguities. That information cycle is embodied through obligatory linkages among energy, biological information, and communication. Successive reiterations of the information cycle enact the informational architectures of the basic unicellular forms. From that base, inter-domain and cell-cell communications enable genetic and cellular variations through self-referential natural informational engineering and cellular niche construction. Holobionts are the exclusive endpoints of that self-referential cellular engineering as obligatory multicellular combinations of the essential Four Domains: Prokaryota, Archaea, Eukaryota and the Virome. Therefore, it is advocated that these Four Domains represent the perpetual object of the living circumstance rather than the visible macroorganic forms. In consequence, biology and its evolutionary development can be appraised as the continual defense of instantiated cellular self-reference. As the survival of cells is as dependent upon limitations and boundaries as upon any freedom of action, it is proposed that selection represents only one of many forms of cellular constraint that sustain self-referential integrity. Copyright © 2018 Elsevier Ltd. All rights reserved.

  4. Impact of network structure on the capacity of wireless multihop ad hoc communication

    NASA Astrophysics Data System (ADS)

    Krause, Wolfram; Glauche, Ingmar; Sollacher, Rudolf; Greiner, Martin

    2004-07-01

    As a representative of a complex technological system, the so-called wireless multihop ad hoc communication networks are discussed. They represent an infrastructure-less generalization of todays wireless cellular phone networks. Lacking a central control authority, the ad hoc nodes have to coordinate themselves such that the overall network performs in an optimal way. A performance indicator is the end-to-end throughput capacity. Various models, generating differing ad hoc network structure via differing transmission power assignments, are constructed and characterized. They serve as input for a generic data traffic simulation as well as some semi-analytic estimations. The latter reveal that due to the most-critical-node effect the end-to-end throughput capacity sensitively depends on the underlying network structure, resulting in differing scaling laws with respect to network size.

  5. Mobile text messaging solutions for obesity prevention

    NASA Astrophysics Data System (ADS)

    Akopian, David; Jayaram, Varun; Aaleswara, Lakshmipathi; Esfahanian, Moosa; Mojica, Cynthia; Parra-Medina, Deborah; Kaghyan, Sahak

    2011-02-01

    Cellular telephony has become a bright example of co-evolution of human society and information technology. This trend has also been reflected in health care and health promotion projects which included cell phones in data collection and communication chain. While many successful projects have been realized, the review of phone-based data collection techniques reveals that the existing technologies do not completely address health promotion research needs. The paper presents approaches which close this gap by extending existing versatile platforms. The messaging systems are designed for a health-promotion research to prevent obesity and obesity-related health disparities among low-income Latino adolescent girls. Messaging and polling mechanisms are used to communicate and automatically process response data for the target constituency. Preliminary survey data provide an insight on phone availability and technology perception for the study group.

  6. Articular chondrocyte network mediated by gap junctions: role in metabolic cartilage homeostasis.

    PubMed

    Mayan, Maria D; Gago-Fuentes, Raquel; Carpintero-Fernandez, Paula; Fernandez-Puente, Patricia; Filgueira-Fernandez, Purificacion; Goyanes, Noa; Valiunas, Virginijus; Brink, Peter R; Goldberg, Gary S; Blanco, Francisco J

    2015-01-01

    This study investigated whether chondrocytes within the cartilage matrix have the capacity to communicate through intercellular connections mediated by voltage-gated gap junction (GJ) channels. Frozen cartilage samples were used for immunofluorescence and immunohistochemistry assays. Samples were embedded in cacodylate buffer before dehydration for scanning electron microscopy. Co-immunoprecipitation experiments and mass spectrometry (MS) were performed to identify proteins that interact with the C-terminal end of Cx43. GJ communication was studied through in situ electroporation, electrophysiology and dye injection experiments. A transwell layered culture system and MS were used to identify and quantify transferred amino acids. Microscopic images revealed the presence of multiple cellular projections connecting chondrocytes within the matrix. These projections were between 5 and 150 µm in length. MS data analysis indicated that the C-terminus of Cx43 interacts with several cytoskeletal proteins implicated in Cx trafficking and GJ assembly, including α-tubulin and β-tubulin, actin, and vinculin. Electrophysiology experiments demonstrated that 12-mer oligonucleotides could be transferred between chondrocytes within 12 min after injection. Glucose was homogeneously distributed within 22 and 35 min. No transfer was detected when glucose was electroporated into A549 cells, which have no GJs. Transwell layered culture systems coupled with MS analysis revealed connexins can mediate the transfer of L-lysine and L-arginine between chondrocytes. This study reveals that intercellular connections between chondrocytes contain GJs that play a key role in cell-cell communication and a metabolic function by exchange of nutrients including glucose and essential amino acids. A three-dimensional cellular network mediated through GJs might mediate metabolic and physiological homeostasis to maintain cartilage tissue. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  7. Toward a North American Standard for Mobile Data Services

    NASA Technical Reports Server (NTRS)

    Dean, Richard A.; Levesque, Allen H.

    1991-01-01

    The rapid introduction of digital mobile communications systems is an important part of the emerging digital communications scene. These developments pose both a potential problem and a challenge. On one hand, these separate market driven developments can result in an uncontrolled mixture of analog and digital links which inhibit data modem services across the mobile/Public Switched network (PSTN). On the other hand, the near coincidence of schedules for development of some of these systems, i.e., Digital Cellular, Mobile Satellite, Land Mobile Radio, and ISDN, provides an opportunity to address interoperability problems by defining interfaces, control, and service standards that are compatible among these new services. In this paper we address the problem of providing data services interoperation between mobile terminals and data devices on the PSTN. The expected data services include G3 Fax, asynchronous data, and the government's STU-3 secure voice system, and future data services such as ISDN. We address a common architecture and a limited set of issues that are key to interoperable mobile data services. We believe that common mobile data standards will both improve the quality of data service and simplify the systems for manufacturers, data users, and service providers.

  8. A hybrid mobile-based patient location tracking system for personal healthcare applications.

    PubMed

    Chew, S H; Chong, P A; Gunawan, E; Goh, K W; Kim, Y; Soh, C B

    2006-01-01

    In the next generation of Infocommunications, mobile Internet-enabled devices and third generation mobile communication networks have become reality, location based services (LBS) are expected to be a major area of growth. Providing information, content and services through positioning technologies forms the platform for new services for users and developers, as well as creating new revenue channels for service providers. These crucial advances in location based services have opened up new opportunities in real time patient tracking for personal healthcare applications. In this paper, a hybrid mobile-based location technique using the global positioning system (GPS) and cellular mobile network infrastructure is employed to provide the location tracking capability. This function will be integrated into the patient location tracking system (PLTS) to assist caregivers or family members in locating patients such as elderly or dependents when required, especially in emergencies. The capability of this PLTS is demonstrated through a series of location detection tests conducted over different operating conditions. Although the model is at its initial stage of development, it has shown relatively good accuracy for position tracking and potential of using integrated wireless technology to enhance the existing personal healthcare communication system through location based services.

  9. Toward a North American standard for mobile data services

    NASA Astrophysics Data System (ADS)

    Dean, Richard A.; Levesque, Allen H.

    1991-09-01

    The rapid introduction of digital mobile communications systems is an important part of the emerging digital communications scene. These developments pose both a potential problem and a challenge. On one hand, these separate market driven developments can result in an uncontrolled mixture of analog and digital links which inhibit data modem services across the mobile/Public Switched network (PSTN). On the other hand, the near coincidence of schedules for development of some of these systems, i.e., Digital Cellular, Mobile Satellite, Land Mobile Radio, and ISDN, provides an opportunity to address interoperability problems by defining interfaces, control, and service standards that are compatible among these new services. In this paper we address the problem of providing data services interoperation between mobile terminals and data devices on the PSTN. The expected data services include G3 Fax, asynchronous data, and the government's STU-3 secure voice system, and future data services such as ISDN. We address a common architecture and a limited set of issues that are key to interoperable mobile data services. We believe that common mobile data standards will both improve the quality of data service and simplify the systems for manufacturers, data users, and service providers.

  10. Clinical, Cellular, and Molecular Aspects in the Pathophysiology of Rosacea

    PubMed Central

    Steinhoff, Martin; Buddenkotte, Jörg; Aubert, Jerome; Sulk, Mathias; Novak, Pawel; Schwab, Verena D.; Mess, Christian; Cevikbas, Ferda; Rivier, Michel; Carlavan, Isabelle; Déret, Sophie; Rosignoli, Carine; Metze, Dieter; Luger, Thomas A.; Voegel, Johannes J.

    2013-01-01

    Rosacea is a chronic inflammatory skin disease of unknown etiology. Although described centuries ago, the pathophysiology of this disease is still poorly understood. Epidemiological studies indicate a genetic component, but a rosacea gene has not been identified yet. Four subtypes and several variants of rosacea have been described. It is still unclear whether these subtypes represent a “developmental march” of different stages or are merely part of a syndrome that develops independently but overlaps clinically. Clinical and histopathological characteristics of rosacea make it a fascinating “human disease model” for learning about the connection between the cutaneous vascular, nervous, and immune systems. Innate immune mechanisms and dysregulation of the neurovascular system are involved in rosacea initiation and perpetuation, although the complex network of primary induction and secondary reaction of neuroimmune communication is still unclear. Later, rosacea may result in fibrotic facial changes, suggesting a strong connection between chronic inflammatory processes and skin fibrosis development. This review highlights recent molecular (gene array) and cellular findings and aims to integrate the different body defense mechanisms into a modern concept of rosacea pathophysiology. PMID:22076321

  11. Gap-junction-mediated communication in human periodontal ligament cells.

    PubMed

    Kato, R; Ishihara, Y; Kawanabe, N; Sumiyoshi, K; Yoshikawa, Y; Nakamura, M; Imai, Y; Yanagita, T; Fukushima, H; Kamioka, H; Takano-Yamamoto, T; Yamashiro, T

    2013-07-01

    Periodontal tissue homeostasis depends on a complex cellular network that conveys cell-cell communication. Gap junctions (GJs), one of the intercellular communication systems, are found between adjacent human periodontal ligament (hPDL) cells; however, the functional GJ coupling between hPDL cells has not yet been elucidated. In this study, we investigated functional gap-junction-mediated intercellular communication in isolated primary hPDL cells. SEM images indicated that the cells were in contact with each other via dendritic processes, and also showed high anti-connexin43 (Cx43) immunoreactivity on these processes. Gap-junctional intercellular communication (GJIC) among hPDL cells was assessed by fluorescence recovery after a photobleaching (FRAP) analysis, which exhibited dye coupling between hPDL cells, and was remarkably down-regulated when the cells were treated with a GJ blocker. Additionally, we examined GJs under hypoxic stress. The fluorescence recovery and expression levels of Cx43 decreased time-dependently under the hypoxic condition. Exposure to GJ inhibitor or hypoxia increased RANKL expression, and decreased OPG expression. This study shows that GJIC is responsible for hPDL cells and that its activity is reduced under hypoxia. This is consistent with the possible role of hPDL cells in regulating the biochemical reactions in response to changes in the hypoxic environment.

  12. Evidence that the tri-cellular metabolism of N-acetylaspartate functions as the brain's "operating system": how NAA metabolism supports meaningful intercellular frequency-encoded communications.

    PubMed

    Baslow, Morris H

    2010-11-01

    N-acetylaspartate (NAA), an acetylated derivative of L-aspartate (Asp), and N-acetylaspartylglutamate (NAAG), a derivative of NAA and L-glutamate (Glu), are synthesized by neurons in brain. However, neurons cannot catabolize either of these substances, and so their metabolism requires the participation of two other cell types. Neurons release both NAA and NAAG to extra-cellular fluid (ECF) upon stimulation, where astrocytes, the target cells for NAAG, hydrolyze it releasing NAA back into ECF, and oligodendrocytes, the target cells for NAA, hydrolyze it releasing Asp to ECF for recycling to neurons. This sequence is unique as it is the only known amino acid metabolic cycle in brain that requires three cell types for its completion. The results of this cycling are two-fold. First, neuronal metabolic water is transported to ECF for its removal from brain. Second, the rate of neuronal activity is coupled with focal hyperemia, providing stimulated neurons with the energy required for transmission of meaningful frequency-encoded messages. In this paper, it is proposed that the tri-cellular metabolism of NAA functions as the "operating system" of the brain, and is essential for normal cognitive and motor activities. Evidence in support of this hypothesis is provided by the outcomes of two human inborn errors in NAA metabolism.

  13. A Study of Future Communications Concepts and Technologies for the National Airspace System-Part III

    NASA Technical Reports Server (NTRS)

    Ponchak, Denise S.; Apaza, Rafael D.; Wichgersm Joel M.; Haynes, Brian; Roy, Aloke

    2014-01-01

    The National Aeronautics and Space Administration (NASA) Glenn Research Center (GRC) is investigating current and anticipated wireless communications concepts and technologies that the National Airspace System (NAS) may need in the next 50 years. NASA has awarded three NASA Research Announcements (NAR) studies with the objective to determine the most promising candidate technologies for air-to-air and air-to-ground data exchange and analyze their suitability in a post-NextGen NAS environment. This paper will present progress made in the studies and describe the communications challenges and opportunities that have been identified as part of the study. NASA's NextGen Concepts and Technology Development (CTD) Project integrates solutions for a safe, efficient and high-capacity airspace system through joint research efforts and partnerships with other government agencies. The CTD Project is one of two within NASA's Airspace Systems Program and is managed by the NASA Ames Research Center. Research within the CTD Project is in support the 2011 NASA Strategic Plan Sub-Goal 4.1: Develop innovative solutions and advanced technologies, through a balanced research portfolio, to improve current and future air transportation. The focus of CTD is on developing capabilities in traffic flow management, dynamic airspace configuration, separation assurance, super density operations and airport surface operations. Important to its research is the development of human/automation information requirements and decisionmaking guidelines for human-human and human-machine airportal decision-making. Airborne separation, oceanic intrail climb/descent and interval management applications depend on location and intent information of surrounding aircraft. ADS-B has been proposed to provide the information exchange, but other candidates such as satellite-based receivers, broadband or airborne internet, and cellular communications are possible candidate's.

  14. Auditory Signal Processing in Communication: Perception and Performance of Vocal Sounds

    PubMed Central

    Prather, Jonathan F.

    2013-01-01

    Learning and maintaining the sounds we use in vocal communication require accurate perception of the sounds we hear performed by others and feedback-dependent imitation of those sounds to produce our own vocalizations. Understanding how the central nervous system integrates auditory and vocal-motor information to enable communication is a fundamental goal of systems neuroscience, and insights into the mechanisms of those processes will profoundly enhance clinical therapies for communication disorders. Gaining the high-resolution insight necessary to define the circuits and cellular mechanisms underlying human vocal communication is presently impractical. Songbirds are the best animal model of human speech, and this review highlights recent insights into the neural basis of auditory perception and feedback-dependent imitation in those animals. Neural correlates of song perception are present in auditory areas, and those correlates are preserved in the auditory responses of downstream neurons that are also active when the bird sings. Initial tests indicate that singing-related activity in those downstream neurons is associated with vocal-motor performance as opposed to the bird simply hearing itself sing. Therefore, action potentials related to auditory perception and action potentials related to vocal performance are co-localized in individual neurons. Conceptual models of song learning involve comparison of vocal commands and the associated auditory feedback to compute an error signal that is used to guide refinement of subsequent song performances, yet the sites of that comparison remain unknown. Convergence of sensory and motor activity onto individual neurons points to a possible mechanism through which auditory and vocal-motor signals may be linked to enable learning and maintenance of the sounds used in vocal communication. PMID:23827717

  15. Communication devices in the operating room.

    PubMed

    Ruskin, Keith J

    2006-12-01

    Effective communication is essential to patient safety. Although radio pagers have been the cornerstone of medical communication, new devices such as cellular telephones, personal digital assistants (PDAs), and laptop or tablet computers can help anesthesiologists to get information quickly and reliably. Anesthesiologists can use these devices to speak with colleagues, access the medical record, or help a colleague in another location without having to leave a patient's side. Recent advances in communication technology offer anesthesiologists new ways to improve patient care. Anesthesiologists rely on a wide variety of information to make decisions, including vital signs, laboratory values, and entries in the medical record. Devices such as PDAs and computers with wireless networking can be used to access this information. Mobile telephones can be used to get help or ask for advice, and are more efficient than radio pagers. Voice over Internet protocol is a new technology that allows voice conversations to be routed over computer networks. It is widely believed that wireless devices can cause life-threatening interference with medical devices. The actual risk is very low, and is offset by a significant reduction in medical errors that results from more efficient communication. Using common technology like cellular telephones and wireless networks is a simple, cost-effective way to improve patient care.

  16. Electronics Manufacturer Provided With Testing and Evaluation Data Necessary to Obtain Additional Orders

    NASA Technical Reports Server (NTRS)

    1998-01-01

    A local electronics manufacturer, the Sterling Manufacturing Company, was presented with the opportunity to supply 30,000 automotive cellular antennas to a European subsidiary of a large U.S. auto manufacturer. Although the company built an antenna that they believed would meet the auto manufacturer's specifications, they were unable to conduct the necessary validation tests in-house. They decided to work with NASA Lewis Research Center's Space Electronics Division, which, as part of its technology development program, evaluates the performance of antennas in its Microwave Systems Lab to assess their capabilities for space communications applications. Data measured in Lewis' Microwave Systems Lab proved that Sterling's antenna performed better than specified by the auto manufacturer.

  17. Probing cooperative force generation in collective cancer invasion

    NASA Astrophysics Data System (ADS)

    Alobaidi, Amani A.; Xu, Yaopengxiao; Chen, Shaohua; Jiao, Yang; Sun, Bo

    2017-08-01

    Collective cellular dynamics in the three-dimensional extracellular matrix (ECM) plays a crucial role in many physiological processes such as cancer invasion. Both chemical and mechanical signaling support cell-cell communications on a variety of length scales, leading to collective migratory behaviors. Here we conduct experiments using 3D in vitro tumor models and develop a phenomenological model in order to probe the cooperativity of force generation in the collective invasion of breast cancer cells. In our model, cell-cell communication is characterized by a single parameter that quantifies the correlation length of cellular migration cycles. We devise a stochastic reconstruction method to generate realizations of cell colonies with specific contraction phase correlation functions and correlation length a. We find that as a increases, the characteristic size of regions containing cells with similar contraction phases grows. For small a values, the large fluctuations in individual cell contraction phases smooth out the temporal fluctuations in the time-dependent deformation field in the ECM. For large a values, the periodicity of an individual cell contraction cycle is clearly manifested in the temporal variation of the overall deformation field in the ECM. Through quantitative comparisons of the simulated and experimentally measured deformation fields, we find that the correlation length for collective force generation in the breast cancer diskoid in geometrically micropatterned ECM (DIGME) system is a≈ 25~μ \\text{m} , which is roughly twice the linear size of a single cell. One possible mechanism for this intermediate cell correlation length is the fiber-mediated stress propagation in the 3D ECM network in the DIGME system.

  18. Novel method for water vapour monitoring using wireless communication networks measurements

    NASA Astrophysics Data System (ADS)

    David, N.; Alpert, P.; Messer, H.

    2010-09-01

    We propose a new technique for monitoring near-surface water vapour, by estimating humidity from data collected through existing wireless communication networks. Weather conditions and atmospheric phenomena affect the electromagnetic channel, causing attenuations to the radio signals. Thus, wireless communication networks are in effect built-in environmental monitoring facilities. The wireless microwave links, used in these networks, are widely deployed by cellular providers for backhaul communication between base stations, a few tens of meters above ground level. As a result, if all available measurements are used, the proposed method can provide moisture observations with high spatial resolution and potentially high temporal resolution. Further, the implementation cost is minimal, since the data used are already collected and saved by the cellular operators. In addition - many of these links are installed in areas where access is difficult such as orographic terrain and complex topography. As such, our method enables measurements in places that have been hard to measure in the past, or have never been measured before. The technique is restricted to weather conditions which exclude rain, fog or clouds along the propagation path. Strong winds that may cause movement of the link transmitter or receiver (or both) may also interfere with the ability to conduct accurate measurements. We present results from real-data measurements taken from microwave links used in a backhaul cellular network that show very good correlation with surface station humidity measurements (comparisons were performed for several links, found at different locations, during different time periods, showing correlations in the range of 0.5-0.9).

  19. Collective Calcium Signaling of Defective Multicellular Networks

    NASA Astrophysics Data System (ADS)

    Potter, Garrett; Sun, Bo

    2015-03-01

    A communicating multicellular network processes environmental cues into collective cellular dynamics. We have previously demonstrated that, when excited by extracellular ATP, fibroblast monolayers generate correlated calcium dynamics modulated by both the stimuli and gap junction communication between the cells. However, just as a well-connected neural network may be compromised by abnormal neurons, a tissue monolayer can also be defective with cancer cells, which typically have down regulated gap junctions. To understand the collective cellular dynamics in a defective multicellular network we have studied the calcium signaling of co-cultured breast cancer cells and fibroblast cells in various concentrations of ATP delivered through microfluidic devices. Our results demonstrate that cancer cells respond faster, generate singular spikes, and are more synchronous across all stimuli concentrations. Additionally, fibroblast cells exhibit persistent calcium oscillations that increase in regularity with greater stimuli. To interpret these results we quantitatively analyzed the immunostaining of purigenic receptors and gap junction channels. The results confirm our hypothesis that collective dynamics are mainly determined by the availability of gap junction communications.

  20. Neuroimmune Axes of the Blood–Brain Barriers and Blood–Brain Interfaces: Bases for Physiological Regulation, Disease States, and Pharmacological Interventions

    PubMed Central

    Erickson, Michelle A.

    2018-01-01

    Central nervous system (CNS) barriers predominantly mediate the immune-privileged status of the brain, and are also important regulators of neuroimmune communication. It is increasingly appreciated that communication between the brain and immune system contributes to physiologic processes, adaptive responses, and disease states. In this review, we discuss the highly specialized features of brain barriers that regulate neuroimmune communication in health and disease. In section I, we discuss the concept of immune privilege, provide working definitions of brain barriers, and outline the historical work that contributed to the understanding of CNS barrier functions. In section II, we discuss the unique anatomic, cellular, and molecular characteristics of the vascular blood–brain barrier (BBB), blood–cerebrospinal fluid barrier, and tanycytic barriers that confer their functions as neuroimmune interfaces. In section III, we consider BBB-mediated neuroimmune functions and interactions categorized as five neuroimmune axes: disruption, responses to immune stimuli, uptake and transport of immunoactive substances, immune cell trafficking, and secretions of immunoactive substances. In section IV, we discuss neuroimmune functions of CNS barriers in physiologic and disease states, as well as pharmacological interventions for CNS diseases. Throughout this review, we highlight many recent advances that have contributed to the modern understanding of CNS barriers and their interface functions. PMID:29496890

  1. Role of cellular communication in the pathways of radiation-induced biological damage

    NASA Astrophysics Data System (ADS)

    Ballarini, Francesca; Facoetti, Angelica; Mariotti, Luca; Nano, Rosanna; Ottolenghi, Andrea

    During the last decade, a large number of experimental studies on the so-called "non-targeted effects", in particular bystander effects, outlined that cellular communication plays a signifi- cant role in the pathways leading to radiation-induced biological damage. This might imply a paradigm shift in (low-dose) radiobiology, according to which one has to consider the response of groups of cells behaving like a population rather than single cells behaving as individuals. Furthermore, bystander effects, which are observed both for lethal endpoints (e.g. clonogenic inactivation and apoptosis) and for non-lethal ones (e.g. mutations and neoplastic transformation), tend to show non-linear dose responses characterized by a sharp increase followed by a plateau. This might have significant consequences in terms of low-dose risk, which is generally calculated on the basis of the "Linear No Threshold" hypothesis. Although it is known that two types of cellular communication (i.e. via gap junctions and/or molecular messengers diffusing in the extra-cellular environment, such as cytokines) play a major role, it is of utmost importance to better understand the underlying mechanisms, and how such mechanisms can be modulated by ionizing radiation. Though the "final" goal is to elucidate the in vivo scenario, in the meanwhile also in vitro studies can provide useful insights. In the present paper we will discuss key issues on the mechanisms underlying non-targeted effects and, more generally, cell communication, with focus on candidate molecular signals. Theoretical models and simulation codes can be of help in elucidating such mechanisms. In this framework, we will present a model and Monte Carlo code, under development at the University of Pavia, simulating the release, diffusion and internalization of candidate signals (typically cytokines) travelling in the extra-cellular environment, both by unirradiated (i.e., control) cells and by irradiated cells. The focus will be on the role of critical parameters such as the cell number and density, the amount of culture medium etc. Comparisons with ad hoc experimental data obtained in our laboratory will be presented, and possible implications in terms of low-dose risk assessment will be discussed. Work supported by the European Community (projects "RISC-RAD" and "NOTE") and the Italian Space Agency (project "MoMa/COUNT)

  2. Energy Efficient IoT Data Collection in Smart Cities Exploiting D2D Communications.

    PubMed

    Orsino, Antonino; Araniti, Giuseppe; Militano, Leonardo; Alonso-Zarate, Jesus; Molinaro, Antonella; Iera, Antonio

    2016-06-08

    Fifth Generation (5G) wireless systems are expected to connect an avalanche of "smart" objects disseminated from the largest "Smart City" to the smallest "Smart Home". In this vision, Long Term Evolution-Advanced (LTE-A) is deemed to play a fundamental role in the Internet of Things (IoT) arena providing a large coherent infrastructure and a wide wireless connectivity to the devices. However, since LTE-A was originally designed to support high data rates and large data size, novel solutions are required to enable an efficient use of radio resources to convey small data packets typically exchanged by IoT applications in "smart" environments. On the other hand, the typically high energy consumption required by cellular communications is a serious obstacle to large scale IoT deployments under cellular connectivity as in the case of Smart City scenarios. Network-assisted Device-to-Device (D2D) communications are considered as a viable solution to reduce the energy consumption for the devices. The particular approach presented in this paper consists in appointing one of the IoT smart devices as a collector of all data from a cluster of objects using D2D links, thus acting as an aggregator toward the eNodeB. By smartly adapting the Modulation and Coding Scheme (MCS) on the communication links, we will show it is possible to maximize the radio resource utilization as a function of the total amount of data to be sent. A further benefit that we will highlight is the possibility to reduce the transmission power when a more robust MCS is adopted. A comprehensive performance evaluation in a wide set of scenarios will testify the achievable gains in terms of energy efficiency and resource utilization in the envisaged D2D-based IoT data collection.

  3. Energy Efficient IoT Data Collection in Smart Cities Exploiting D2D Communications

    PubMed Central

    Orsino, Antonino; Araniti, Giuseppe; Militano, Leonardo; Alonso-Zarate, Jesus; Molinaro, Antonella; Iera, Antonio

    2016-01-01

    Fifth Generation (5G) wireless systems are expected to connect an avalanche of “smart” objects disseminated from the largest “Smart City” to the smallest “Smart Home”. In this vision, Long Term Evolution-Advanced (LTE-A) is deemed to play a fundamental role in the Internet of Things (IoT) arena providing a large coherent infrastructure and a wide wireless connectivity to the devices. However, since LTE-A was originally designed to support high data rates and large data size, novel solutions are required to enable an efficient use of radio resources to convey small data packets typically exchanged by IoT applications in “smart” environments. On the other hand, the typically high energy consumption required by cellular communications is a serious obstacle to large scale IoT deployments under cellular connectivity as in the case of Smart City scenarios. Network-assisted Device-to-Device (D2D) communications are considered as a viable solution to reduce the energy consumption for the devices. The particular approach presented in this paper consists in appointing one of the IoT smart devices as a collector of all data from a cluster of objects using D2D links, thus acting as an aggregator toward the eNodeB. By smartly adapting the Modulation and Coding Scheme (MCS) on the communication links, we will show it is possible to maximize the radio resource utilization as a function of the total amount of data to be sent. A further benefit that we will highlight is the possibility to reduce the transmission power when a more robust MCS is adopted. A comprehensive performance evaluation in a wide set of scenarios will testify the achievable gains in terms of energy efficiency and resource utilization in the envisaged D2D-based IoT data collection. PMID:27338385

  4. XBP1, Unfolded Protein Response, and Endocrine Responsiveness

    DTIC Science & Technology

    2012-05-01

    cancer resistance problems. While perhaps not all of the criteria apply, getting the scientific community to engineer an agreed solution could well...a more intimate relationship between apoptosis and autophagy, implying sig- nificant communication between these 2 activities. Such com- munication...localization. Cellular signaling occurs in the context of interactive networks (58, 97), and a considerable degree of integration and communication

  5. Cooperative Interference Alignment for the Multiple Access Channel

    DTIC Science & Technology

    2015-11-01

    Communications. I. INTRODUCTION Conventional wireless networks were previously thought to be interference-limited, where interference is mainly caused by...interference-free capacity for any number of users K at high SNR. This fundamental result showed that wireless networks are not interference-limited as...decoding of the K users’ messages. This is applicable in uplink transmissions in cellular communications, where mobiles transmit independent messages

  6. Simplified power control method for cellular mobile communication

    NASA Astrophysics Data System (ADS)

    Leung, Y. W.

    1994-04-01

    The centralized power control (CPC) method measures the gain of the communication links between every mobile and every base station in the cochannel cells and determines optimal transmitter power to maximize the minimum carrier-to-interference ratio. The authors propose a simplified power control method which has nearly the same performance as the CPC method but which involves much smaller measurement overhead.

  7. A secretome analysis reveals that PPARα is upregulated by fractionated-dose γ-irradiation in three-dimensional keratinocyte cultures

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

    Lee, Jeeyong; Kim, Hyun-Ji; Yi, Jae Youn, E-mail: yjy_71@kcch.re.kr

    Studies have shown that γ-irradiation induces various biological responses, including oxidative stress and apoptosis, as well as cellular repair and immune system responses. However, most such studies have been performed using traditional two-dimensional cell culture systems, which are limited in their ability to faithfully represent in vivo conditions. A three-dimensional (3D) environment composed of properly interconnected and differentiated cells that allow communication and cooperation among cells via secreted molecules would be expected to more accurately reflect cellular responses. Here, we investigated γ-irradiation–induced changes in the secretome of 3D-cultured keratinocytes. An analysis of keratinocyte secretome profiles following fractionated-dose γ-irradiation revealed changes inmore » genes involved in cell adhesion, angiogenesis, and the immune system. Notably, peroxisome proliferator-activated receptor-α (PPARα) was upregulated in response to fractionated-dose γ-irradiation. This upregulation was associated with an increase in the transcription of known PPARα target genes in secretome, including angiopoietin-like protein 4, dermokine and kallikrein-related peptide 12, which were differentially regulated by fractionated-dose γ-irradiation. Collectively, our data imply a mechanism linking γ-irradiation and secretome changes, and suggest that these changes could play a significant role in the coordinated cellular responses to harmful ionizing radiation, such as those associated with radiation therapy. This extension of our understanding of γ-irradiation-induced secretome changes has the potential to improve radiation therapy strategies. - Highlights: • γ-irradiation induced changes of cell adhesion, angiogenesis, and immune system in secretome of 3D-cultured keratinocytes. • Peroxisome proliferator-activated receptor-α (PPARα) was upregulated in response to fractionated-dose γ-irradiation. • The known PPARα target genes were differentially regulated by fractionated-dose γ-irradiation.« less

  8. Endoplasmic Reticulum-Plasma Membrane Contacts Regulate Cellular Excitability.

    PubMed

    Dickson, Eamonn J

    2017-01-01

    Cells that have intrinsic electrical excitability utilize changes in membrane potential to communicate with neighboring cells and initiate cellular cascades. Excitable cells like neurons and myocytes have evolved highly specialized subcellular architectures to translate these electrical signals into cellular events. One such structural specialization is sarco-/endoplasmic reticulum-plasma membrane contact sites. These membrane contact sites are positioned by specific membrane-membrane tethering proteins and contain an ever-expanding list of additional proteins that organize information transfer across the junctional space (~ 15-25 nm distance) to shape membrane identity and control cellular excitability. In this chapter we discuss how contacts between the sarco-/endoplasmic reticulum and plasma membrane are essential for regulated excitation-contraction coupling in striated muscle and control of lipid-dependent ion channels.

  9. Novel method for fog monitoring using cellular networks infrastructures

    NASA Astrophysics Data System (ADS)

    David, N.; Alpert, P.; Messer, H.

    2012-08-01

    A major detrimental effect of fog is visibility limitation which can result in serious transportation accidents, traffic delays and therefore economic damage. Existing monitoring techniques including satellites, transmissometers and human observers - suffer from low spatial resolution, high cost or lack of precision when measuring near ground level. Here we show a novel technique for fog monitoring using wireless communication systems. Communication networks widely deploy commercial microwave links across the terrain at ground level. Operating at frequencies of tens of GHz they are affected by fog and are, effectively, an existing, spatially world-wide distributed sensor network that can provide crucial information about fog concentration and visibility. Fog monitoring potential is demonstrated for a heavy fog event that took place in Israel. The correlation between transmissomters and human eye observations to the visibility estimates from the nearby microwave links was found to be 0.53 and 0.61, respectively. These values indicate the high potential of the proposed method.

  10. Endogenous opioids regulate moment-to-moment neuronal communication and excitability.

    PubMed

    Winters, Bryony L; Gregoriou, Gabrielle C; Kissiwaa, Sarah A; Wells, Oliver A; Medagoda, Danashi I; Hermes, Sam M; Burford, Neil T; Alt, Andrew; Aicher, Sue A; Bagley, Elena E

    2017-03-22

    Fear and emotional learning are modulated by endogenous opioids but the cellular basis for this is unknown. The intercalated cells (ITCs) gate amygdala output and thus regulate the fear response. Here we find endogenous opioids are released by synaptic stimulation to act via two distinct mechanisms within the main ITC cluster. Endogenously released opioids inhibit glutamate release through the δ-opioid receptor (DOR), an effect potentiated by a DOR-positive allosteric modulator. Postsynaptically, the opioids activate a potassium conductance through the μ-opioid receptor (MOR), suggesting for the first time that endogenously released opioids directly regulate neuronal excitability. Ultrastructural localization of endogenous ligands support these functional findings. This study demonstrates a new role for endogenously released opioids as neuromodulators engaged by synaptic activity to regulate moment-to-moment neuronal communication and excitability. These distinct actions through MOR and DOR may underlie the opposing effect of these receptor systems on anxiety and fear.

  11. Demonstration of novel, secure, real-time, portable ultrasound transmission from an austere international location.

    PubMed

    Ogedegbe, Chinwe; Morchel, Herman; Hazelwood, Vikki; Hassler, Cynthia; Feldman, Joseph

    2012-01-01

    There is not sufficient access to medical care or medical expertise in many parts of the world. An innovative telemedicine system has been developed to provide expert medical guidance to field caregivers [who have less medical expertise but can reach the patient population in need]. Real-time ultrasound video images have been securely transmitted from the Dominican Republic to Hackensack University Medical Center, Hackensack NJ (HackensackUMC), while the expert physician at HackensackUMC maintained direct voice communication with the field caregiver. Utilizing a portable ultrasound machine (Sonosite) integrated with portable broadcasting device (LiveU), extended Focused Assessment Sonography in Trauma (e-FAST) examinations were performed on healthy volunteers and transmitted via the local cellular network. Additionally, two e-FAST examinations were conducted from a remote location without cellular coverage and transmitted via broad ground area network (BGAN) satellites. The demonstration took the technology "out of the lab" and into a real life, austere environment. The conditions of the Dominican Republic ultrasound mission provided experience on how to manage and utilize this innovative technology in areas where reliable communications and medical coverage are not readily available. The resilient transmission capabilities coupled with the security features deem this portable Telesonography (TS) equipment highly useful in the telemedicine forefront by offering healthcare in underdeveloped areas as well as potentially enhancing throughput in disaster situations.

  12. 47 CFR 22.901 - Cellular service requirements and limitations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.901 Cellular service requirements and limitations. The licensee of each cellular system is responsible for ensuring that its cellular system operates in compliance with this section. (a) Each cellular system must provide either mobile service...

  13. Digital divide: variation in internet and cellular phone use among women attending an urban sexually transmitted infections clinic.

    PubMed

    Samal, Lipika; Hutton, Heidi E; Erbelding, Emily J; Brandon, Elizabeth S; Finkelstein, Joseph; Chander, Geetanjali

    2010-01-01

    We sought to describe: (1) the prevalence of internet, cellular phone, and text message use among women attending an urban sexually transmitted infections (STI) clinic, (2) the acceptability of health advice by each mode of information and communication technology (ICT), and (3) demographic characteristics associated with ICT use. This study is a cross-sectional survey of 200 English-speaking women presenting to a Baltimore City STI clinic with STI complaints. Participants completed a self-administered survey querying ICT use and demographic characteristics. Three separate questions asked about interest in receiving health advice delivered by the three modalities: internet, cellular phone, and text message. We performed logistic regression to examine how demographic factors (age, race, and education) are associated with likelihood of using each modality. The median age of respondents was 27 years; 87% were African American, and 71% had a high school diploma. The rate of any internet use was 80%; 31% reported daily use; 16% reported weekly use; and 32% reported less frequent use. Almost all respondents (93%) reported cellular phone use, and 79% used text messaging. Acceptability of health advice by each of the three modalities was about 60%. In multivariate analysis, higher education and younger age were associated with internet use, text messaging, and cellular phone use. Overall rate of internet use was high, but there was an educational disparity in internet use. Cellular phone use was almost universal in this sample. All three modalities were equally acceptable forms of health communication. Describing baseline ICT access and the acceptability of health advice via ICT, as we have done, is one step toward determining the feasibility of ICT-delivered health interventions in urban populations.

  14. Risk perception and public concerns of electromagnetic waves from cellular phones in Korea.

    PubMed

    Kim, Kyunghee; Kim, Hae-Joon; Song, Dae Jong; Cho, Yong Min; Choi, Jae Wook

    2014-05-01

    In this study, the difference between the risk perception of electromagnetic waves from cellular phones and the risk perception of other factors such as environment and food was analyzed. The cause of the difference in the psychological and social factors that affect the group with high risk perception of electromagnetic waves was also analyzed. A questionnaire survey on the risk perception of electromagnetic waves from cellular phones was carried out on 1001 subjects (men and women) over the age of 20. In the group with high risk perception of electromagnetic waves from cellular phones, women had higher risk perception than men. Logistic regression analysis, where the group with high risk perception of electromagnetic waves and the group with low risk perception were used as dependent variables, indicated that the risk perception of electromagnetic waves in women was 1.815 times statistically significantly higher than the risk perception of men (95% CI: 1.340-2.457). Also, high risk perception of electromagnetic waves from cellular phones was observed when the subjects considered that they had more personal knowledge (OR: 1.416, 95% CI: 1.216-1.648), that the seriousness of the risk to future generations was high (OR: 1.410, 95% CI: 1.234-1.611), and their outrage for the occurrence of accidents related to electromagnetic waves was high (OR: 1.460, 95% CI: 1.264-1.686). The results of this study need to be sufficiently considered and reflected in designing the risk communication strategies and communication methods for the preventive measures and advice on electromagnetic waves from cellular phones. © 2014 Wiley Periodicals, Inc.

  15. Rapid GNSS and Data Communication System Deployments In Chile and Argentina Following the M8.8 Maule Earthquake

    NASA Astrophysics Data System (ADS)

    Blume, F.; Meertens, C. M.; Brooks, B. A.; Bevis, M. G.; Smalley, R.; Parra, H.; Baez, J.

    2010-12-01

    Because the signal is so big, great earthquakes allow us to make quantum leaps in our understanding of Earth deformation process and material properties. The Maule earthquake, with its occurrence near a large subaerial landmass and the large numbers of instruments available to study it, will surely become one of the most important geophysical events in modern memory. Much of the important signal, however, decays and changes rapidly in the short-term following the event and so a rapid response is necessary. Actually delivering the data from the CGPS response stations, however, represents an intellectual challenge in terms of properly matching the engineering realities with the scientific desiderata. We expect multiple major science advances to come from these data: (1) Understanding earthquake and tsunami-genesis via use of the coseismic displacement field to create the most well-constrained fault slip and tsunami-genesis models. (2) The role of stress loading on both the principal thrust plane and subsidiary planes. (3) The relationship between fault afterslip to the main event as well as to the distribution of aftershocks (4) Study of large aftershocks jointly using conventional seismology and high-rate GPS coseismic displacement seismogram. (5) Rheological behavior of the fault interface. (6) The mechanical response of the bulk earth to large stress perturbations. Within 10 days of the earthquake 20 complete GPS systems were delivered by UNAVCO personnel to IGM and OSU staff in Santiago, and 5 were shipped via diplomatic pouch to Argentina. Consisting of of 10 Trimble NetRS and 15 Topcon GB-1000 receivers, the units were deployed througout the affected area during the following three weeks, using welded-in-place steel tripod monuments driven into soil or drilled into bedrock, or steel masts. Additional GPS hardware was procured from cooperating institutions and donated by GPS manufacturers, and a total of 43 post-earthquake GPS stations are continuously operating in the epicentral area. UNAVCO has developed and deplyed standalone data communications systems at 25 of the stations: (1) the satellite-based Inmarsat Broad Global Area Service (BGAN), (2) ground based cellular internet services provided by a number of telecom companies in Chile and Argentina. Cellular service is economical but prone to disruptions following earthquakes and coverage is limited. BGAN is expensive but robust and globally available. This communication plan has allowed for daily downloads of 15 sec. data and of 1 sec. data recorded during aftershocks of M6.5 and greater. RINEX files from these stations are publicly available at the UNAVCO Facility Archive immediately after data are downloaded, a first for Event Response GPS data. This effort will serve as the type example in the geodetic community for rapid CGPS data communications following a destructive earthquake. The communications system hardware purchased during this response will become part of the UNAVCO pool after one year and will be available for future PI projects and event responses.

  16. Connexins, pannexins and their channels in fibroproliferative diseases

    PubMed Central

    Willebrords, Joost; Da Silva, Tereza Cristina; Maes, Michaël; Pereira, Isabel Veloso Alves; Crespo-Yanguas, Sara; Hernandez-Blazquez, Francisco Javier; Dagli, Maria Lúcia Zaidan; Vinken, Mathieu

    2017-01-01

    Cellular and molecular mechanisms of wound healing, tissue repair and fibrogenesis are established in different organs and are essential for the maintenance of function and tissue integrity after cell injury. These mechanisms are also involved in a plethora of fibroproliferative diseases or organ-specific fibrotic disorders, all of which are associated with the excessive deposition of extracellular matrix components. Fibroblasts, which are key cells in tissue repair and fibrogenesis, rely on communicative cellular networks to ensure efficient control of these processes and to prevent abnormal accumulation of extracellular matrix into the tissue. Despite the significant impact on human health, and thus the epidemiologic relevance, there is still no effective treatment for most fibrosis-related diseases. This paper provides an overview of current concepts and mechanisms involved in the participation of cellular communication via connexin-based pores as well as pannexin-based channels in the processes of tissue repair and fibrogenesis in chronic diseases. Understanding these mechanisms may contribute to the development of new therapeutic strategies to clinically manage fibroproliferative diseases and organ-specific fibrotic disorders. PMID:26914707

  17. Biomedical digital assistant for ubiquitous healthcare.

    PubMed

    Lee, Tae-Soo; Hong, Joo-Hyun; Cho, Myeong-Chan

    2007-01-01

    The concept of ubiquitous healthcare service, which emerged as one of measures to solve healthcare problems in aged society, means that patients can receive services such as prevention, diagnosis, therapy and prognosis management at any time and in any place with the help of advanced information and communication technology. This service requires not only biomedical digital assistant that can monitor continuously the patients' health condition regardless of time and place, but also wired and wireless communication devices and telemedicine servers that provide doctors with data on patients' present health condition. In order to implement a biomedical digital assistant that is portable and wearable to patients, the present study developed a device that minimizes size, weight and power consumption, measures ECG and PPG signals, and even monitors moving patients' state. The biomedical sensor with the function of wireless communication was designed to be highly portable and wearable, to be operable 24 hours with small-size batteries, and to monitor the subject's heart rate, step count and respiratory rate in his daily life. The biomedical signal receiving device was implemented in two forms, PDA and cellular phone. The movement monitoring device embedded in the battery pack of a cellular phone does not have any problem in operating 24 hours, but the real-time biomedical signal receiving device implemented with PDA operated up to 6 hours due to the limited battery capacity of PDA. This problem is expected to be solved by reducing wireless communication load through improving the processing and storage functions of the sensor. The developed device can transmit a message on the patient's emergency to the remote server through the cellular phone network, and is expected to play crucial roles in the health management of chronic-aged patients in their daily life.

  18. Novel method for water vapour monitoring using wireless communication networks measurements

    NASA Astrophysics Data System (ADS)

    David, N.; Alpert, P.; Messer, H.

    2009-04-01

    We propose a new technique for monitoring near-surface water vapour, by estimating humidity from data collected through existing wireless communication networks. Water vapour plays a crucial part in a variety of atmospheric processes. As the most influential of greenhouse gases, it absorbs long-wave terrestrial radiation. The water vapour cycle of evaporation and recondensation is a major energy redistributing mechanism transferring heat energy from the Earth's surface to the atmosphere. Additionally, humidity has an important role in weather forecasting as a key variable required for initialization of atmospheric models and hazard warning techniques. However, current methods of monitoring humidity suffer from low spatial resolution, high cost or a lack of precision when measuring near ground levels. Weather conditions and atmospheric phenomena affect the electromagnetic channel, causing attenuations to the radio signals. Thus, wireless communication networks are in effect built-in environmental monitoring facilities. The wireless microwave links, used in these networks, are widely deployed by cellular providers for backhaul communication between base stations, a few tens of meters above ground level. As a result, the proposed method can provide moisture observations at high temporal and spatial resolution. Further, the implementation cost is minimal, since the data used is already collected and saved by the cellular operators. In addition - many of these links are installed in areas where access is difficult such as orographic terrain and complex topography. As such, our method enables measurements in places that have been hard to measure in the past, or have never been measured before. The technique is restricted to weather conditions which include absence of rain, fog or clouds along the propagation path. We present results from real-data measurements taken from microwave links used in a backhaul cellular network that show very good agreement with surface station humidity measurements.

  19. [The Functional Role of Exosomes in Cancer Biology and Their Potential as Biomarkers and Therapeutic Targets of Cancer].

    PubMed

    Naito, Yutaka; Yoshioka, Yusuke; Ochiya, Takahiro

    2015-06-01

    Intercellular communication plays an important role in the regulation of various cellular events. In particular, cancer cells and the surrounding cells communicate with each other, and this intercellular communication triggers cancer initiation and progression through the secretion of molecules, including growth factors and cytokines. Recent advances in cancer biology have indicated that small membrane vesicles, termed exosomes, also serve as regulatory agents in intercellular communications. Exosomes contain functional cellular components, including proteins and microRNAs (miRNAs), and they transfer these components to recipient cells. This exosome-mediated intercellular communication leads to increased growth, invasion, and metastasis of cancer. Thus, researchers regard exosomes as important cues to understanding the molecular mechanisms of cancer biology. Indeed, several lines of evidence have demonstrated that exosomes can explain multiple aspects of cancer biology. In addition, increasing evidence suggests that exosomes and their specific molecules are also attractive for use as biomarkers and therapeutic targets in cancer. Recent reports showed the efficacy of a novel diagnosis by detecting component molecules of cancer-derived exosomes, including miRNAs and membrane proteins. Furthermore, clinical trials that test the application of exosomes for cancer therapy have already been reported. From these points of view, we will summarize experimental data that support the role of exosomes in cancer progression and the potential of exosomes for use in novel diagnostic and therapeutic approaches for cancer.

  20. A reprogrammable receiver architecture for wireless signal interception

    NASA Astrophysics Data System (ADS)

    Yao, Timothy S.

    2003-09-01

    In this paper, a re-programmable receiver architecture, based on software-defined-radio concept, for wireless signal interception is presented. The radio-frequency (RF) signal that the receiver would like to intercept may come from a terrestrial cellular network or communication satellites, which their carrier frequency are in the range from 800 MHz (civilian mobile) to 15 GHz (Ku band). To intercept signals from such a wide range of frequency in these variant communication systems, the traditional way is to deploy multiple receivers to scan and detect the desired signal. This traditional approach is obviously unattractive due to the cost, efficiency, and accuracy. Instead, we propose a universal receiver, which is software-driven and re-configurable, to intercept signals of interest. The software-defined-radio based receiver first intercepts RF energy of wide spectrum (25MHz) through antenna, performs zero-IF down conversion (homodyne architecture) to baseband, and digital channelizes the baseband signal. The channelization module is a bank of high performance digital filters. The bandwidth of the filter bank is programmable according to the wireless communication protocol under watch. In the baseband processing, high-performance digital signal processors carry out the detection process and microprocessors handle the communication protocols. The baseband processing is also re-configurable for different wireless standards and protocol. The advantages of the software-defined-radio architecture over traditional RF receiver make it a favorable technology for the communication signal interception and surveillance.

  1. Seeking the foundations of cognition in bacteria: From Schrödinger's negative entropy to latent information

    NASA Astrophysics Data System (ADS)

    Ben Jacob, Eshel; Shapira, Yoash; Tauber, Alfred I.

    2006-01-01

    We reexamine Schrödinger's reflections on the fundamental requirements for life in view of new observations about bacterial self-organization and the emerging understanding of gene-network regulation mechanisms and dynamics. Focusing on the energy, matter and thermodynamic imbalances provided by the environment, Schrödinger proposed his consumption of negative entropy requirement for life. We take the criteria further and propose that, besides “negative entropy”, organisms extract latent information embedded in the complexity of their environment. By latent information we refer to the non-arbitrary spatio-temporal patterns of regularities and variations that characterize the environmental dynamics. Hence it can be used to generate an internal condensed description (model or usable information) of the environment which guides the organisms functioning. Accordingly, we propose that Schrödinger's criterion of “consumption of negative entropy” is not sufficient and “consumption of latent information” is an additional fundamental requirement of Life. In other words, all organisms, including bacteria, the most primitive (fundamental) ones, must be able to sense the environment and perform internal information processing for thriving on latent information embedded in the complexity of their environment. We then propose that by acting together, bacteria can perform this most elementary cognitive function more efficiently as can be illustrated by their cooperative behavior (colonial or inter-cellular self-organization). As a member of a complex superorganism-the colony-each unit (bacteria) must possess the ability to sense and communicate with the other units comprising the collective and perform its task within a distribution of tasks. Bacterial communication thus entails collective sensing and cooperativity. The fundamental (primitive) elements of cognition in such systems include interpretation of (chemical) messages, distinction between internal and external information, and some self vs., non-self distinction (peers and cheaters). We outline how intra-cellular self-organization together with genome plasticity and membrane dynamics might, in principle, provide the intra-cellular mechanisms needed for these fundamental cognitive functions. In regard to intra-cellular processes, Schrödinger postulated that new physics is needed to explain the convertion of the genetically stored information into a functioning cell. At present, his ontogenetic dilemma is generally perceived to be solved and is attributed to a lack of knowledge when it was proposed. So it is widely accepted that there is no need for some unknown laws of physics to explain cellular ontogenetic development. We take a different view and in Schrödinger's foot steps suggest that yet unknown physics principles of self-organization in open systems are missing for understanding how to assemble the cell's component into an information-based functioning “machine”.

  2. Comparison of neural network applications for channel assignment in cellular TDMA networks and dynamically sectored PCS networks

    NASA Astrophysics Data System (ADS)

    Hortos, William S.

    1997-04-01

    The use of artificial neural networks (NNs) to address the channel assignment problem (CAP) for cellular time-division multiple access and code-division multiple access networks has previously been investigated by this author and many others. The investigations to date have been based on a hexagonal cell structure established by omnidirectional antennas at the base stations. No account was taken of the use of spatial isolation enabled by directional antennas to reduce interference between mobiles. Any reduction in interference translates into increased capacity and consequently alters the performance of the NNs. Previous studies have sought to improve the performance of Hopfield- Tank network algorithms and self-organizing feature map algorithms applied primarily to static channel assignment (SCA) for cellular networks that handle uniformly distributed, stationary traffic in each cell for a single type of service. The resulting algorithms minimize energy functions representing interference constraint and ad hoc conditions that promote convergence to optimal solutions. While the structures of the derived neural network algorithms (NNAs) offer the potential advantages of inherent parallelism and adaptability to changing system conditions, this potential has yet to be fulfilled the CAP for emerging mobile networks. The next-generation communication infrastructures must accommodate dynamic operating conditions. Macrocell topologies are being refined to microcells and picocells that can be dynamically sectored by adaptively controlled, directional antennas and programmable transceivers. These networks must support the time-varying demands for personal communication services (PCS) that simultaneously carry voice, data and video and, thus, require new dynamic channel assignment (DCA) algorithms. This paper examines the impact of dynamic cell sectoring and geometric conditioning on NNAs developed for SCA in omnicell networks with stationary traffic to improve the metrics of convergence rate and call blocking. Genetic algorithms (GAs) are also considered in PCS networks as a means to overcome the known weakness of Hopfield NNAs in determining global minima. The resulting GAs for DCA in PCS networks are compared to improved DCA algorithms based on Hopfield NNs for stationary cellular networks. Algorithm performance is compared on the basis of rate of convergence, blocking probability, analytic complexity, and parametric sensitivity to transient traffic demands and channel interference.

  3. 47 CFR 22.970 - Unacceptable interference to part 90 non-cellular 800 MHz licensees from cellular radiotelephone...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...-cellular 800 MHz licensees from cellular radiotelephone or part 90-800 MHz cellular systems. 22.970 Section... MOBILE SERVICES Cellular Radiotelephone Service § 22.970 Unacceptable interference to part 90 non-cellular 800 MHz licensees from cellular radiotelephone or part 90-800 MHz cellular systems. (a) Definition...

  4. Microfluidic Approaches for Isolation, Detection, and Characterization of Extracellular Vesicles: Current Status and Future Directions

    PubMed Central

    Gholizadeh, Shima; Draz, Mohamed; Zarghooni, Maryam; Nezhad, Amir Sanati; Ghavami, Saeid; Shafiee, Hadi; Akbari, Mohsen

    2017-01-01

    Extracellular vesicles (EVs) are cell-derived vesicles present in body fluids that play an essential role in various cellular processes, such as intercellular communication, inflammation, cellular homeostasis, survival, transport, and regeneration. Their isolation and analysis from body fluids have a great clinical potential to provide information on a variety of disease states such as cancer, cardiovascular complication and inflammatory disorders. Despite increasing scientific and clinical interest in this field, at the time of writing there are still no standardized procedures available for the purification, detection, and characterization of EVs. Advances in microfluidics allow for chemical sampling with increasingly high spatial resolution and under precise manipulation down to single molecule level. In this review, our objective is to give a brief overview on the working principle and examples of the isolation and detection methods with the potential to be used for extracellular vesicles. This review will also highlight the integrated on-chip systems for isolation and characterization of EVs. PMID:28088752

  5. Mitochondria in lung disease

    PubMed Central

    Cloonan, Suzanne M.; Choi, Augustine M.K.

    2016-01-01

    Mitochondria are a distinguishing feature of eukaryotic cells. Best known for their critical function in energy production via oxidative phosphorylation (OXPHOS), mitochondria are essential for nutrient and oxygen sensing and for the regulation of critical cellular processes, including cell death and inflammation. Such diverse functional roles for organelles that were once thought to be simple may be attributed to their distinct heteroplasmic genome, exclusive maternal lineage of inheritance, and ability to generate signals to communicate with other cellular organelles. Mitochondria are now thought of as one of the cell’s most sophisticated and dynamic responsive sensing systems. Specific signatures of mitochondrial dysfunction that are associated with disease pathogenesis and/or progression are becoming increasingly important. In particular, the centrality of mitochondria in the pathological processes and clinical phenotypes associated with a range of lung diseases is emerging. Understanding the molecular mechanisms regulating the mitochondrial processes of lung cells will help to better define phenotypes and clinical manifestations associated with respiratory disease and to identify potential diagnostic and therapeutic targets. PMID:26928034

  6. A transwell assay that excludes exosomes for assessment of tunneling nanotube-mediated intercellular communication.

    PubMed

    Thayanithy, Venugopal; O'Hare, Patrick; Wong, Phillip; Zhao, Xianda; Steer, Clifford J; Subramanian, Subbaya; Lou, Emil

    2017-11-13

    Tunneling nanotubes (TNTs) are naturally-occurring filamentous actin-based membranous extensions that form across a wide spectrum of mammalian cell types to facilitate long-range intercellular communication. Valid assays are needed to accurately assess the downstream effects of TNT-mediated transfer of cellular signals in vitro. We recently reported a modified transwell assay system designed to test the effects of intercellular transfer of a therapeutic oncolytic virus, and viral-activated drugs, between cells via TNTs. The objective of the current study was to demonstrate validation of this in vitro approach as a new method for effectively excluding diffusible forms of long- and close-range intercellular transfer of intracytoplasmic cargo, including exosomes/microvesicles and gap junctions in order to isolate TNT-selective cell communication. We designed several steps to effectively reduce or eliminate diffusion and long-range transfer via these extracellular vesicles, and used Nanoparticle Tracking Analysis to quantify exosomes following implementation of these steps. The experimental approach outlined here effectively reduced exosome trafficking by >95%; further use of heparin to block exosome uptake by putative recipient cells further impeded transfer of these extracellular vesicles. This validated assay incorporates several steps that can be taken to quantifiably control for extracellular vesicles in order to perform studies focused on TNT-selective communication.

  7. Immune Abnormalities in Autism Spectrum Disorder-Could They Hold Promise for Causative Treatment?

    PubMed

    Gładysz, Dominika; Krzywdzińska, Amanda; Hozyasz, Kamil K

    2018-01-06

    Autism spectrum disorders (ASD) are characterized by impairments in language and communication development, social behavior, and the occurrence of stereotypic patterns of behavior and interests. Despite substantial speculation about causes of ASD, its exact etiology remains unknown. Recent studies highlight a link between immune dysfunction and behavioral traits. Various immune anomalies, including humoral and cellular immunity along with abnormalities at the molecular level, have been reported. There is evidence of altered immune function both in cerebrospinal fluid and peripheral blood. Several studies hypothesize a role for neuroinflammation in ASD and are supported by brain tissue and cerebrospinal fluid analysis, as well as evidence of microglial activation. It has been shown that immune abnormalities occur in a substantial number of individuals with ASD. Identifying subgroups with immune system dysregulation and linking specific cellular immunophenotypes to different symptoms would be key to defining a group of patients with immune abnormalities as a major etiology underlying behavioral symptoms. These determinations would provide the opportunity to investigate causative treatments for a defined patient group that may specifically benefit from such an approach. This review summarizes recent insights into immune system dysfunction in individuals with ASD and discusses the potential implications for future therapies.

  8. Space-time dynamics of Stem Cell Niches: a unified approach for Plants.

    PubMed

    Pérez, Maria Del Carmen; López, Alejandro; Padilla, Pablo

    2013-06-01

    Many complex systems cannot be analyzed using traditional mathematical tools, due to their irreducible nature. This makes it necessary to develop models that can be implemented computationally to simulate their evolution. Examples of these models are cellular automata, evolutionary algorithms, complex networks, agent-based models, symbolic dynamics and dynamical systems techniques. We review some representative approaches to model the stem cell niche in Arabidopsis thaliana and the basic biological mechanisms that underlie its formation and maintenance. We propose a mathematical model based on cellular automata for describing the space-time dynamics of the stem cell niche in the root. By making minimal assumptions on the cell communication process documented in experiments, we classify the basic developmental features of the stem-cell niche, including the basic structural architecture, and suggest that they could be understood as the result of generic mechanisms given by short and long range signals. This could be a first step in understanding why different stem cell niches share similar topologies, not only in plants. Also the fact that this organization is a robust consequence of the way information is being processed by the cells and to some extent independent of the detailed features of the signaling mechanism.

  9. Space-time dynamics of stem cell niches: a unified approach for plants.

    PubMed

    Pérez, Maria del Carmen; López, Alejandro; Padilla, Pablo

    2013-04-02

    Many complex systems cannot be analyzed using traditional mathematical tools, due to their irreducible nature. This makes it necessary to develop models that can be implemented computationally to simulate their evolution. Examples of these models are cellular automata, evolutionary algorithms, complex networks, agent-based models, symbolic dynamics and dynamical systems techniques. We review some representative approaches to model the stem cell niche in Arabidopsis thaliana and the basic biological mechanisms that underlie its formation and maintenance. We propose a mathematical model based on cellular automata for describing the space-time dynamics of the stem cell niche in the root. By making minimal assumptions on the cell communication process documented in experiments, we classify the basic developmental features of the stem-cell niche, including the basic structural architecture, and suggest that they could be understood as the result of generic mechanisms given by short and long range signals. This could be a first step in understanding why different stem cell niches share similar topologies, not only in plants. Also the fact that this organization is a robust consequence of the way information is being processed by the cells and to some extent independent of the detailed features of the signaling mechanism.

  10. Microfluidics-based in vivo mimetic systems for the study of cellular biology.

    PubMed

    Kim, Donghyuk; Wu, Xiaojie; Young, Ashlyn T; Haynes, Christy L

    2014-04-15

    The human body is a complex network of molecules, organelles, cells, tissues, and organs: an uncountable number of interactions and transformations interconnect all the system's components. In addition to these biochemical components, biophysical components, such as pressure, flow, and morphology, and the location of all of these interactions play an important role in the human body. Technical difficulties have frequently limited researchers from observing cellular biology as it occurs within the human body, but some state-of-the-art analytical techniques have revealed distinct cellular behaviors that occur only in the context of the interactions. These types of findings have inspired bioanalytical chemists to provide new tools to better understand these cellular behaviors and interactions. What blocks us from understanding critical biological interactions in the human body? Conventional approaches are often too naïve to provide realistic data and in vivo whole animal studies give complex results that may or may not be relevant for humans. Microfluidics offers an opportunity to bridge these two extremes: while these studies will not model the complexity of the in vivo human system, they can control the complexity so researchers can examine critical factors of interest carefully and quantitatively. In addition, the use of human cells, such as cells isolated from donated blood, captures human-relevant data and limits the use of animals in research. In addition, researchers can adapt these systems easily and cost-effectively to a variety of high-end signal transduction mechanisms, facilitating high-throughput studies that are also spatially, temporally, or chemically resolved. These strengths should allow microfluidic platforms to reveal critical parameters in the human body and provide insights that will help with the translation of pharmacological advances to clinical trials. In this Account, we describe selected microfluidic innovations within the last 5 years that focus on modeling both biophysical and biochemical interactions in cellular communication, such as flow and cell-cell networks. We also describe more advanced systems that mimic higher level biological networks, such as organ on-a-chip and animal on-a-chip models. Since the first papers in the early 1990s, interest in the bioanalytical use of microfluidics has grown significantly. Advances in micro-/nanofabrication technology have allowed researchers to produce miniaturized, biocompatible assay platforms suitable for microfluidic studies in biochemistry and chemical biology. Well-designed microfluidic platforms can achieve quick, in vitro analyses on pico- and femtoliter volume samples that are temporally, spatially, and chemically resolved. In addition, controlled cell culture techniques using a microfluidic platform have produced biomimetic systems that allow researchers to replicate and monitor physiological interactions. Pioneering work has successfully created cell-fluid, cell-cell, cell-tissue, tissue-tissue, even organ-like level interfaces. Researchers have monitored cellular behaviors in these biomimetic microfluidic environments, producing validated model systems to understand human pathophysiology and to support the development of new therapeutics.

  11. Inmarsat and personal mobile satellite services

    NASA Astrophysics Data System (ADS)

    McDougal, Patrick; Barendse, Victor

    Personal communications - mobile satellite services (PC-MSS) hold much promise as a profitable business opportunity for a number of interested operators and manufacturers. What will be their impact on the overall mobile communications landscape, and what role will they play in the drive towards the universal personal communicator? It is the thesis of this paper that PC-MSS can provide one of the critical enabling technologies to allow a more rapid, global assimilation of personal mobile communications. Terrestrial mobile communications are local by definition, both in terms of service reach and regulatory oversight. It is estimated that cellular, and other forms of terrestrial mobile communications, will cover over 50% of the world's population, but only 15% of the land mass area by the year 2000. PC-MSS will allow 'cellular extension' to interested users in the uncovered parts of the world. The market opportunity is established and technical solutions are available. However 'user cooperation' will be required and cross mapping of market needs to the technology solutions is the key to financially viable solutions. The potential political and regulatory hurdles are daunting. Inmarsat, as the existing global MSS partnership, is already introducing PC-MSS products and services in the 1990s. The widespread use of briefcase satphones (Inm-M), laptop-sized data terminals (Inm-C), and pocket satpagers (Inm-paging) will break new ground in reshaping the international regulatory context of mobile communications, and in initiating the optimal public switched network integration necessary for global interconnect. It is suggested that this evolutionary approach, by means of international consensus-building within a global partnership of operators, is an effective and proven method to ensure both a sufficient financial return for investors, and fair and equitable access of these services for all countries and users.

  12. Quorum sensing and microbial drug resistance.

    PubMed

    Chen, Yu-fan; Liu, Shi-yin; Liang, Zhi-bin; Lv, Ming-fa; Zhou, Jia-nuan; Zhang, Lian-hui

    2016-10-20

    Microbial drug resistance has become a serious problem of global concern, and the evolution and regulatory mechanisms of microbial drug resistance has become a hotspot of research in recent years. Recent studies showed that certain microbial resistance mechanisms are regulated by quorum sensing system. Quorum sensing is a ubiquitous cell-cell communication system in the microbial world, which associates with cell density. High-density microbial cells produce sufficient amount of small signal molecules, activating a range of downstream cellular processes including virulence and drug resistance mechanisms, which increases bacterial drug tolerance and causes infections on host organisms. In this review, the general mechanisms of microbial drug resistance and quorum-sensing systems are summarized with a focus on the association of quorum sensing and chemical signaling systems with microbial drug resistance mechanisms, including biofilm formation and drug efflux pump. The potential use of quorum quenching as a new strategy to control microbial resistance is also discussed.

  13. Whole-cell biocomputing

    NASA Technical Reports Server (NTRS)

    Simpson, M. L.; Sayler, G. S.; Fleming, J. T.; Applegate, B.

    2001-01-01

    The ability to manipulate systems on the molecular scale naturally leads to speculation about the rational design of molecular-scale machines. Cells might be the ultimate molecular-scale machines and our ability to engineer them is relatively advanced when compared with our ability to control the synthesis and direct the assembly of man-made materials. Indeed, engineered whole cells deployed in biosensors can be considered one of the practical successes of molecular-scale devices. However, these devices explore only a small portion of cellular functionality. Individual cells or self-organized groups of cells perform extremely complex functions that include sensing, communication, navigation, cooperation and even fabrication of synthetic nanoscopic materials. In natural systems, these capabilities are controlled by complex genetic regulatory circuits, which are only partially understood and not readily accessible for use in engineered systems. Here, we focus on efforts to mimic the functionality of man-made information-processing systems within whole cells.

  14. Morphological communication: exploiting coupled dynamics in a complex mechanical structure to achieve locomotion

    PubMed Central

    Rieffel, John A.; Valero-Cuevas, Francisco J.; Lipson, Hod

    2010-01-01

    Traditional engineering approaches strive to avoid, or actively suppress, nonlinear dynamic coupling among components. Biological systems, in contrast, are often rife with these dynamics. Could there be, in some cases, a benefit to high degrees of dynamical coupling? Here we present a distributed robotic control scheme inspired by the biological phenomenon of tensegrity-based mechanotransduction. This emergence of morphology-as-information-conduit or ‘morphological communication’, enabled by time-sensitive spiking neural networks, presents a new paradigm for the decentralized control of large, coupled, modular systems. These results significantly bolster, both in magnitude and in form, the idea of morphological computation in robotic control. Furthermore, they lend further credence to ideas of embodied anatomical computation in biological systems, on scales ranging from cellular structures up to the tendinous networks of the human hand. PMID:19776146

  15. Emission of Biophotons and Adjustable Sounds by the Fascial System: Review and Reflections for Manual Therapy.

    PubMed

    Bordoni, Bruno; Marelli, Fabiola; Morabito, Bruno; Sacconi, Beatrice

    2018-01-01

    Every body structure is wrapped in connective tissue or fascia, creating a structural continuity that gives form and function to every tissue and organ. The fascial tissue is uniformly distributed throughout the body, enveloping, interacting with and permeating blood vessels, nerves, viscera, meninges, bones and muscles, creating various layers at different depths and forming a tridimensional metabolic and mechanical matrix. This article reviews the literature on the emission of biophotons and adjustable sounds by the fascial system, because these biological changes could be a means of local and systemic cellular communication and become another assessment tool for manual (therapy) practitioners. This is the first article that discusses these topics in a single text, attempting to bring such information into an area of application that is beneficial to osteopaths, chiropractors, and manual therapists.

  16. Emission of Biophotons and Adjustable Sounds by the Fascial System: Review and Reflections for Manual Therapy

    PubMed Central

    Marelli, Fabiola; Sacconi, Beatrice

    2018-01-01

    Every body structure is wrapped in connective tissue or fascia, creating a structural continuity that gives form and function to every tissue and organ. The fascial tissue is uniformly distributed throughout the body, enveloping, interacting with and permeating blood vessels, nerves, viscera, meninges, bones and muscles, creating various layers at different depths and forming a tridimensional metabolic and mechanical matrix. This article reviews the literature on the emission of biophotons and adjustable sounds by the fascial system, because these biological changes could be a means of local and systemic cellular communication and become another assessment tool for manual (therapy) practitioners. This is the first article that discusses these topics in a single text, attempting to bring such information into an area of application that is beneficial to osteopaths, chiropractors, and manual therapists. PMID:29405763

  17. Wireless data over RAM's Mobitex network

    NASA Astrophysics Data System (ADS)

    Khan, M. Mobeen

    1995-12-01

    Mobitex is a mobile data technology standard created by Eritel, now a wholly owned subsidiary of Ericsson, that has been in existence for about a decade. Originally designed as a low speed (1.2 kbps) data system with a voice dispatch overlay, it was significantly enhanced in 1990 for use in North America and the UK. The enhanced system is a data-only system using cellular architecture and multi-channel frequency reuse, store-and-forward capability, and an 8 kbps over-the-air data rate. The mission of RAM Mobile Data USA Limited Partnership ('RAM') is to provide high quality, cost efficient, wireless data communications solutions in its targeted market segments. RAM's Mobitex network is currently one of the two networks providing two way wireless data services nationwide using a long distance service provider of the customer's choice.

  18. Development of an electronic medical report delivery system to 3G GSM mobile (cellular) phones for a medical imaging department.

    PubMed

    Lim, Eugene Y; Lee, Chiang; Cai, Weidong; Feng, Dagan; Fulham, Michael

    2007-01-01

    Medical practice is characterized by a high degree of heterogeneity in collaborative and cooperative patient care. Fast and effective communication between medical practitioners can improve patient care. In medical imaging, the fast delivery of medical reports to referring medical practitioners is a major component of cooperative patient care. Recently, mobile phones have been actively deployed in telemedicine applications. The mobile phone is an ideal medium to achieve faster delivery of reports to the referring medical practitioners. In this study, we developed an electronic medical report delivery system from a medical imaging department to the mobile phones of the referring doctors. The system extracts a text summary of medical report and a screen capture of diagnostic medical image in JPEG format, which are transmitted to 3G GSM mobile phones.

  19. Downlink Training Techniques for FDD Massive MIMO Systems: Open-Loop and Closed-Loop Training With Memory

    NASA Astrophysics Data System (ADS)

    Choi, Junil; Love, David J.; Bidigare, Patrick

    2014-10-01

    The concept of deploying a large number of antennas at the base station, often called massive multiple-input multiple-output (MIMO), has drawn considerable interest because of its potential ability to revolutionize current wireless communication systems. Most literature on massive MIMO systems assumes time division duplexing (TDD), although frequency division duplexing (FDD) dominates current cellular systems. Due to the large number of transmit antennas at the base station, currently standardized approaches would require a large percentage of the precious downlink and uplink resources in FDD massive MIMO be used for training signal transmissions and channel state information (CSI) feedback. To reduce the overhead of the downlink training phase, we propose practical open-loop and closed-loop training frameworks in this paper. We assume the base station and the user share a common set of training signals in advance. In open-loop training, the base station transmits training signals in a round-robin manner, and the user successively estimates the current channel using long-term channel statistics such as temporal and spatial correlations and previous channel estimates. In closed-loop training, the user feeds back the best training signal to be sent in the future based on channel prediction and the previously received training signals. With a small amount of feedback from the user to the base station, closed-loop training offers better performance in the data communication phase, especially when the signal-to-noise ratio is low, the number of transmit antennas is large, or prior channel estimates are not accurate at the beginning of the communication setup, all of which would be mostly beneficial for massive MIMO systems.

  20. Cell-to-cell communication in plants, animals, and fungi: a comparative review.

    PubMed

    Bloemendal, Sandra; Kück, Ulrich

    2013-01-01

    Cell-to-cell communication is a prerequisite for differentiation and development in multicellular organisms. This communication has to be tightly regulated to ensure that cellular components such as organelles, macromolecules, hormones, or viruses leave the cell in a precisely organized way. During evolution, plants, animals, and fungi have developed similar ways of responding to this biological challenge. For example, in higher plants, plasmodesmata connect adjacent cells and allow communication to regulate differentiation and development. In animals, two main general structures that enable short- and long-range intercellular communication are known, namely gap junctions and tunneling nanotubes, respectively. Finally, filamentous fungi have also developed specialized structures called septal pores that allow intercellular communication via cytoplasmic flow. This review summarizes the underlying mechanisms for intercellular communication in these three eukaryotic groups and discusses its consequences for the regulation of differentiation and developmental processes.

  1. Cell-to-cell communication in plants, animals, and fungi: a comparative review

    NASA Astrophysics Data System (ADS)

    Bloemendal, Sandra; Kück, Ulrich

    2013-01-01

    Cell-to-cell communication is a prerequisite for differentiation and development in multicellular organisms. This communication has to be tightly regulated to ensure that cellular components such as organelles, macromolecules, hormones, or viruses leave the cell in a precisely organized way. During evolution, plants, animals, and fungi have developed similar ways of responding to this biological challenge. For example, in higher plants, plasmodesmata connect adjacent cells and allow communication to regulate differentiation and development. In animals, two main general structures that enable short- and long-range intercellular communication are known, namely gap junctions and tunneling nanotubes, respectively. Finally, filamentous fungi have also developed specialized structures called septal pores that allow intercellular communication via cytoplasmic flow. This review summarizes the underlying mechanisms for intercellular communication in these three eukaryotic groups and discusses its consequences for the regulation of differentiation and developmental processes.

  2. Microaerophilic conditions permit to mimic in vitro events occurring during in vivo Helicobacter pylori infection and to identify Rho/Ras-associated proteins in cellular signaling.

    PubMed

    Cottet, Sandra; Corthésy-Theulaz, Irène; Spertini, François; Corthésy, Blaise

    2002-09-13

    Molecular dissection of the mechanisms underlying Helicobacter pylori infection suffers from the lack of in vitro systems mimicking in vivo observations. A system was developed whereby human epithelial cells (Caco-2) grown as polarized monolayers and bacteria can communicate with each other under culture conditions optimal for each partner. Caco-2 cells grown on filter supports were inserted in a vertical position into diffusion chambers equilibrated with air and 5% CO(2) at their basolateral surface (aerophilic conditions) and 5% CO(2), 5% O(2), 90% N(2) (microaerophilic conditions) in the apical compartment. Remarkably, the epithelial polarized layer was stable under these asymmetric culture conditions for at least 24 h, and the presence of Caco-2 cells was necessary to maintain H. pylori growth. In contrast to previous studies conducted with non-polarized Caco-2 cells and other cell lines kept under aerophilic conditions, we found H. pylori-dependent stimulation of cytokine secretion (MCP-1 (monocyte chemoattractant protein-1), GRO-alpha (growth-regulated oncogene-alpha), RANTES (regulated on activation normal T cell expressed and secreted)). This correlated with nuclear translocation of NF-kappaB p50 and p65 subunits. Tyrosine phosphorylation of nine cellular proteins was induced or enhanced; we identified p120(RasGAP), p190(RhoGAP), p62dok (downstream of tyrosine kinases), and cortactin as H. pylori-inducible targets. Moreover, reduction of H. pylori urease expression was observed in adherent bacteria as compared with bacteria in suspension. In addition to mimicking several observations seen in the inflamed gastric mucosa, the novel in vitro system was allowed to underscore complex cellular events not seen in classical in vitro analyses of microaerophilic bacteria-epithelial cell cross-talk.

  3. Mesenchymal Stem and Progenitor Cells in Normal and Dysplastic Hematopoiesis—Masters of Survival and Clonality?

    PubMed Central

    Pleyer, Lisa; Valent, Peter; Greil, Richard

    2016-01-01

    Myelodysplastic syndromes (MDS) are malignant hematopoietic stem cell disorders that have the capacity to progress to acute myeloid leukemia (AML). Accumulating evidence suggests that the altered bone marrow (BM) microenvironment in general, and in particular the components of the stem cell niche, including mesenchymal stem cells (MSCs) and their progeny, play a pivotal role in the evolution and propagation of MDS. We here present an overview of the role of MSCs in the pathogenesis of MDS, with emphasis on cellular interactions in the BM microenvironment and related stem cell niche concepts. MSCs have potent immunomodulatory capacities and communicate with diverse immune cells, but also interact with various other cellular components of the microenvironment as well as with normal and leukemic stem and progenitor cells. Moreover, compared to normal MSCs, MSCs in MDS and AML often exhibit altered gene expression profiles, an aberrant phenotype, and abnormal functional properties. These alterations supposedly contribute to the “reprogramming” of the stem cell niche into a disease-permissive microenvironment where an altered immune system, abnormal stem cell niche interactions, and an impaired growth control lead to disease progression. The current article also reviews molecular targets that play a role in such cellular interactions and possibilities to interfere with abnormal stem cell niche interactions by using specific targeted drugs. PMID:27355944

  4. An intrinsic poperty of memory of the Cellular automaton infrastructure of Nature leading to the organization of the physical world as an Internet o things; TOE = IOT

    NASA Astrophysics Data System (ADS)

    Berkovich, Simon

    2015-04-01

    The undamental advantage of a Cellular automaton construction foris that it can be viewed as an undetectable absolute frame o reference, in accordance with Lorentz-Poincare's interpretation.. The cellular automaton model for physical poblems comes upon two basic hurdles: (1) How to find the Elemental Rule that, and how to get non-locality from local transformations. Both problems are resolved considering the transfomation rule of mutual distributed synchronization Actually any information proessing device starts with a clocking system. and it turns out that ``All physical phenomena are different aspects of the high-level description of distributed mutual synchronization in a network of digital clocks''. Non-locality comes from two hugely different time-scales of signaling.. The universe is acombinines information and matter processes, These fast spreading diffusion wave solutions create the mechanism of the Holographic Universe. And thirdly Disengaged from synchronization, circular counters can perform memory functions by retaining phases of their oscillations, an idea of Von Neumann'. Thus, the suggested model generates the necessary constructs for the physical world as an Internet of Things. Life emerges due to the specifics of macromolecules that serve as communication means, with the holographic memory...

  5. A new JPEG-based steganographic algorithm for mobile devices

    NASA Astrophysics Data System (ADS)

    Agaian, Sos S.; Cherukuri, Ravindranath C.; Schneider, Erik C.; White, Gregory B.

    2006-05-01

    Currently, cellular phones constitute a significant portion of the global telecommunications market. Modern cellular phones offer sophisticated features such as Internet access, on-board cameras, and expandable memory which provide these devices with excellent multimedia capabilities. Because of the high volume of cellular traffic, as well as the ability of these devices to transmit nearly all forms of data. The need for an increased level of security in wireless communications is becoming a growing concern. Steganography could provide a solution to this important problem. In this article, we present a new algorithm for JPEG-compressed images which is applicable to mobile platforms. This algorithm embeds sensitive information into quantized discrete cosine transform coefficients obtained from the cover JPEG. These coefficients are rearranged based on certain statistical properties and the inherent processing and memory constraints of mobile devices. Based on the energy variation and block characteristics of the cover image, the sensitive data is hidden by using a switching embedding technique proposed in this article. The proposed system offers high capacity while simultaneously withstanding visual and statistical attacks. Based on simulation results, the proposed method demonstrates an improved retention of first-order statistics when compared to existing JPEG-based steganographic algorithms, while maintaining a capacity which is comparable to F5 for certain cover images.

  6. Mesenchymal Stem and Progenitor Cells in Normal and Dysplastic Hematopoiesis-Masters of Survival and Clonality?

    PubMed

    Pleyer, Lisa; Valent, Peter; Greil, Richard

    2016-06-27

    Myelodysplastic syndromes (MDS) are malignant hematopoietic stem cell disorders that have the capacity to progress to acute myeloid leukemia (AML). Accumulating evidence suggests that the altered bone marrow (BM) microenvironment in general, and in particular the components of the stem cell niche, including mesenchymal stem cells (MSCs) and their progeny, play a pivotal role in the evolution and propagation of MDS. We here present an overview of the role of MSCs in the pathogenesis of MDS, with emphasis on cellular interactions in the BM microenvironment and related stem cell niche concepts. MSCs have potent immunomodulatory capacities and communicate with diverse immune cells, but also interact with various other cellular components of the microenvironment as well as with normal and leukemic stem and progenitor cells. Moreover, compared to normal MSCs, MSCs in MDS and AML often exhibit altered gene expression profiles, an aberrant phenotype, and abnormal functional properties. These alterations supposedly contribute to the "reprogramming" of the stem cell niche into a disease-permissive microenvironment where an altered immune system, abnormal stem cell niche interactions, and an impaired growth control lead to disease progression. The current article also reviews molecular targets that play a role in such cellular interactions and possibilities to interfere with abnormal stem cell niche interactions by using specific targeted drugs.

  7. PI3K/Akt signaling is involved in the disruption of gap junctional communication caused by v-Src and TNF-α.

    PubMed

    Ito, Satoko; Hyodo, Toshinori; Hasegawa, Hitoki; Yuan, Hong; Hamaguchi, Michinari; Senga, Takeshi

    2010-09-17

    Gap junctional communication, which is mediated by the connexin protein family, is essential for the maintenance of normal tissue function and homeostasis. Loss of intercellular communication results in a failure to coordinately regulate cellular functions, and it can facilitate tumorigenesis. Expression of oncogenes and stimulation with cytokines has been shown to suppress intercellular communication; however, the exact mechanism by which intercellular communication is disrupted by these factors remains uncertain. In this report, we show that Akt is essential for the disruption of gap junctional communication in v-Src-transformed cells. In addition, inhibition of Akt restores gap junctional communication after it is suppressed by TNF-α signaling. Furthermore, we demonstrate that the expression of a constitutively active form of Akt1, but not of Akt2 or Akt3, is sufficient to suppress gap junctional communication. Our results clearly define Akt1 as one of the critical regulators of gap junctional communication. Copyright © 2010 Elsevier Inc. All rights reserved.

  8. Navigating the Perfect Storm: Research Strategies for Socialecological Systems in a Rapidly Evolving World

    NASA Astrophysics Data System (ADS)

    Dearing, John A.; Bullock, Seth; Costanza, Robert; Dawson, Terry P.; Edwards, Mary E.; Poppy, Guy M.; Smith, Graham M.

    2012-04-01

    The `Perfect Storm' metaphor describes a combination of events that causes a surprising or dramatic impact. It lends an evolutionary perspective to how social-ecological interactions change. Thus, we argue that an improved understanding of how social-ecological systems have evolved up to the present is necessary for the modelling, understanding and anticipation of current and future social-ecological systems. Here we consider the implications of an evolutionary perspective for designing research approaches. One desirable approach is the creation of multi-decadal records produced by integrating palaeoenvironmental, instrument and documentary sources at multiple spatial scales. We also consider the potential for improved analytical and modelling approaches by developing system dynamical, cellular and agent-based models, observing complex behaviour in social-ecological systems against which to test systems dynamical theory, and drawing better lessons from history. Alongside these is the need to find more appropriate ways to communicate complex systems, risk and uncertainty to the public and to policy-makers.

  9. Complementation of non-tumorigenicity of HPV18-positive cervical carcinoma cells involves differential mRNA expression of cellular genes including potential tumor suppressor genes on chromosome 11q13.

    PubMed

    Kehrmann, Angela; Truong, Ha; Repenning, Antje; Boger, Regina; Klein-Hitpass, Ludger; Pascheberg, Ulrich; Beckmann, Alf; Opalka, Bertram; Kleine-Lowinski, Kerstin

    2013-01-01

    The fusion between human tumorigenic cells and normal human diploid fibroblasts results in non-tumorigenic hybrid cells, suggesting a dominant role for tumor suppressor genes in the generated hybrid cells. After long-term cultivation in vitro, tumorigenic segregants may arise. The loss of tumor suppressor genes on chromosome 11q13 has been postulated to be involved in the induction of the tumorigenic phenotype of human papillomavirus (HPV)18-positive cervical carcinoma cells and their derived tumorigenic hybrid cells after subcutaneous injection in immunocompromised mice. The aim of this study was the identification of novel cellular genes that may contribute to the suppression of the tumorigenic phenotype of non-tumorigenic hybrid cells in vivo. We used cDNA microarray technology to identify differentially expressed cellular genes in tumorigenic HPV18-positive hybrid and parental HeLa cells compared to non-tumorigenic HPV18-positive hybrid cells. We detected several as yet unknown cellular genes that play a role in cell differentiation, cell cycle progression, cell-cell communication, metastasis formation, angiogenesis, antigen presentation, and immune response. Apart from the known differentially expressed genes on 11q13 (e.g., phosphofurin acidic cluster sorting protein 1 (PACS1) and FOS ligand 1 (FOSL1 or Fra-1)), we detected novel differentially expressed cellular genes located within the tumor suppressor gene region (e.g., EGF-containing fibulin-like extracellular matrix protein 2 (EFEMP2) and leucine rich repeat containing 32 (LRRC32) (also known as glycoprotein-A repetitions predominant (GARP)) that may have potential tumor suppressor functions in this model system of non-tumorigenic and tumorigenic HeLa x fibroblast hybrid cells. Copyright © 2013 Elsevier Inc. All rights reserved.

  10. Commercial wireless technologies for public safety users

    DOT National Transportation Integrated Search

    2000-07-01

    This report on commercial wireless for public safety addresses the issues associated with the use of commercial services for public safety. It then reviews available wireless services for wide area data services: cellular, personal communication and ...

  11. Deciphering plant-pathogen communication: fresh perspectives for molecular resistance breeding.

    PubMed

    Hammond-Kosack, Kim E; Parker, Jane E

    2003-04-01

    Activation of local and systemic plant defences in response to pathogen attack involves dramatic cellular reprogramming. Over the past 10 years many novel genes, proteins and molecules have been discovered as a result of investigating plant-pathogen interactions. Most attempts to harness this knowledge to engineer improved disease resistance in crops have failed. Although gene efficacy in transgenic plants has often been good, commercial exploitation has not been possible because of the detrimental effects on plant growth, development and crop yield. Biotechnology approaches have now shifted emphasis towards marker-assisted breeding and the construction of vectors containing highly regulated transgenes that confer resistance in several distinct ways.

  12. Marine optical characterizations

    NASA Technical Reports Server (NTRS)

    Clark, Dennis K.; Ge, Yuntao; Hovey, Phil; King, ED; Stengel, Eric; Yuen, Marilyn; Koval, Larisa

    1995-01-01

    During the past three months, the MOCE Team conducted two field experiments in Mill Creek,Chesapeake Bay, from July 24 to August 4, and at the MOBY operations site at Snug Harbor, Honolulu, Hawaii, from August 15-30, prepared two technical memoranda, and continued MOCE-2 and MOCE-3 data reduction. The primary purposes of the experiments were to test the SeaWiFS 'remote sensing reflectance' protocol, obtain turbid water data for ocean color satellite algorithm development, perform calibration for both Near Infrared (NIR) and Visible Rainbow Spectrometer system, continue assembling the operational Marine Optical Buoy, and to test the MOBY cellular phone communications link at the Lanai mooring site.

  13. Cellular phones and their hazards: the current evidence.

    PubMed

    Munshi, Anusheel; Jalali, Rakesh

    2002-01-01

    The past decade has seen an exponential increase globally in the use of cellular phones (popularly known as mobile or cell phones). These phones are convenient and trendy. Discarding the wire means that the communication is through electromagnetic waves, which could have potential hazards. Alarmist reports in the lay press and high profile lawsuits, particularly in the West, have attracted attention to the possible harmful effects of cellular phones. Adverse effects investigated by various clinical trials include the possible link to increased risk of vehicular accidents, leukaemias, sleep disturbances and the more serious brain tumours. Available level II evidence suggests that the only proven side-effect is an increased risk of vehicular accidents. So far, all studies have consistently negated any association between cellular phones and brain tumours. Yet, the final word remains to be said.

  14. International Symposiun on Biological Reactive Intermediates: Molecular and Cellular Effects and Their Impact on Human Health (4th) Held in Tucson, Arizona on 14-17 January 1990

    DTIC Science & Technology

    1991-04-03

    477 Robert A. Roth, and James F. Reindel Reactive Oxygen Species in the Progression of CC14-1nduced Liver Injury ...COMMUNICATIONS CCl4 -Induced Cytochrome P-4S0 Loss and Lipid Peroxldation In Rat Liver Slices ........................... 669 Shana Azri, Heriberto P. Mata, A...VII. Cellular Consequences of BRI Session VIII. Interactions Between Liver and Other Celis by BR! Session IX. Messenger Mediated Intraorgan Effects

  15. Research in Biological and Medical Sciences Including Biochemistry, Communicable Disease and Immunology, Internal Medicine, Nuclear Medicine, Physiology, Psychiatry, Surgery, and Veterinary Medicine. Volume 2

    DTIC Science & Technology

    1974-06-30

    Sprinz and Formal 1968). Fat seen in colonic epithelial cells of monkeys infected by Shigella flexneri occurred before penetration of...cellular or non-cellular components of the peripheral blood such as fat , fibrin, denatured protein, red blood cells, intact neutrophils or other...in vitro, and imply their embolic character when infused into the recipient’s vasculature. Corclusion Storage of whole blood under normal blood bank

  16. Flexible substrata for the detection of cellular traction forces

    NASA Technical Reports Server (NTRS)

    Beningo, Karen A.; Wang, Yu-Li

    2002-01-01

    By modulating adhesion signaling and cytoskeletal organization, mechanical forces play an important role in various cellular functions, from propelling cell migration to mediating communication between cells. Recent developments have resulted in several new approaches for the detection, analysis and visualization of mechanical forces generated by cultured cells. Combining these methods with other approaches, such as green-fluorescent protein (GFP) imaging and gene manipulation, proves to be particularly powerful for analyzing the interplay between extracellular physical forces and intracellular chemical events.

  17. Wireless technology in the ICU: boon or ban?

    PubMed

    Gladman, Aviv S; Lapinsky, Stephen E

    2007-01-01

    Wireless communication and data transmission are playing an increasing role in the critical care environment. Early anecdotal reports of electromagnetic interference (EMI) with intensive care unit (ICU) equipment resulted in many institutions banning these devices. An increasing literature database has more clearly defined the risks of EMI. Restrictions to the use of mobile devices are being lifted, and it has been suggested that the benefits of improved communication may outweigh the small risks. However, increased use of cellular phones and ever changing communication technologies require ongoing vigilance by healthcare device manufacturers, hospitals and device users, to prevent potentially hazardous events due to EMI.

  18. Information, Physics, and Cancer

    NASA Astrophysics Data System (ADS)

    Adami, Chris

    Many researchers have doubts that a ''theory of cancer'' can exist, given the fact that there are so many different cancer phenotypes. However, such a situation-many significantly different manifestations of an underlying law-is not at all uncommon in physics. I argue that a unified cause for all forms of cancer is possible, but that such a theory must be cast in terms of information and communication theory. I briefly revisit key concepts of that theory, then discuss possible applications to communication in game theory that could lead us to view cancer as a disease that, at its root, is a cellular failure to properly communicate.

  19. Cell-to-Cell Communication Circuits: Quantitative Analysis of Synthetic Logic Gates

    PubMed Central

    Hoffman-Sommer, Marta; Supady, Adriana; Klipp, Edda

    2012-01-01

    One of the goals in the field of synthetic biology is the construction of cellular computation devices that could function in a manner similar to electronic circuits. To this end, attempts are made to create biological systems that function as logic gates. In this work we present a theoretical quantitative analysis of a synthetic cellular logic-gates system, which has been implemented in cells of the yeast Saccharomyces cerevisiae (Regot et al., 2011). It exploits endogenous MAP kinase signaling pathways. The novelty of the system lies in the compartmentalization of the circuit where all basic logic gates are implemented in independent single cells that can then be cultured together to perform complex logic functions. We have constructed kinetic models of the multicellular IDENTITY, NOT, OR, and IMPLIES logic gates, using both deterministic and stochastic frameworks. All necessary model parameters are taken from literature or estimated based on published kinetic data, in such a way that the resulting models correctly capture important dynamic features of the included mitogen-activated protein kinase pathways. We analyze the models in terms of parameter sensitivity and we discuss possible ways of optimizing the system, e.g., by tuning the culture density. We apply a stochastic modeling approach, which simulates the behavior of whole populations of cells and allows us to investigate the noise generated in the system; we find that the gene expression units are the major sources of noise. Finally, the model is used for the design of system modifications: we show how the current system could be transformed to operate on three discrete values. PMID:22934039

  20. Microfluidics-Based in Vivo Mimetic Systems for the Study of Cellular Biology

    PubMed Central

    2015-01-01

    Conspectus The human body is a complex network of molecules, organelles, cells, tissues, and organs: an uncountable number of interactions and transformations interconnect all the system’s components. In addition to these biochemical components, biophysical components, such as pressure, flow, and morphology, and the location of all of these interactions play an important role in the human body. Technical difficulties have frequently limited researchers from observing cellular biology as it occurs within the human body, but some state-of-the-art analytical techniques have revealed distinct cellular behaviors that occur only in the context of the interactions. These types of findings have inspired bioanalytical chemists to provide new tools to better understand these cellular behaviors and interactions. What blocks us from understanding critical biological interactions in the human body? Conventional approaches are often too naïve to provide realistic data and in vivo whole animal studies give complex results that may or may not be relevant for humans. Microfluidics offers an opportunity to bridge these two extremes: while these studies will not model the complexity of the in vivo human system, they can control the complexity so researchers can examine critical factors of interest carefully and quantitatively. In addition, the use of human cells, such as cells isolated from donated blood, captures human-relevant data and limits the use of animals in research. In addition, researchers can adapt these systems easily and cost-effectively to a variety of high-end signal transduction mechanisms, facilitating high-throughput studies that are also spatially, temporally, or chemically resolved. These strengths should allow microfluidic platforms to reveal critical parameters in the human body and provide insights that will help with the translation of pharmacological advances to clinical trials. In this Account, we describe selected microfluidic innovations within the last 5 years that focus on modeling both biophysical and biochemical interactions in cellular communication, such as flow and cell–cell networks. We also describe more advanced systems that mimic higher level biological networks, such as organ on-a-chip and animal on-a-chip models. Since the first papers in the early 1990s, interest in the bioanalytical use of microfluidics has grown significantly. Advances in micro-/nanofabrication technology have allowed researchers to produce miniaturized, biocompatible assay platforms suitable for microfluidic studies in biochemistry and chemical biology. Well-designed microfluidic platforms can achieve quick, in vitro analyses on pico- and femtoliter volume samples that are temporally, spatially, and chemically resolved. In addition, controlled cell culture techniques using a microfluidic platform have produced biomimetic systems that allow researchers to replicate and monitor physiological interactions. Pioneering work has successfully created cell–fluid, cell–cell, cell–tissue, tissue–tissue, even organ-like level interfaces. Researchers have monitored cellular behaviors in these biomimetic microfluidic environments, producing validated model systems to understand human pathophysiology and to support the development of new therapeutics. PMID:24555566

  1. Computational Methods for Biomolecular Electrostatics

    PubMed Central

    Dong, Feng; Olsen, Brett; Baker, Nathan A.

    2008-01-01

    An understanding of intermolecular interactions is essential for insight into how cells develop, operate, communicate and control their activities. Such interactions include several components: contributions from linear, angular, and torsional forces in covalent bonds, van der Waals forces, as well as electrostatics. Among the various components of molecular interactions, electrostatics are of special importance because of their long range and their influence on polar or charged molecules, including water, aqueous ions, and amino or nucleic acids, which are some of the primary components of living systems. Electrostatics, therefore, play important roles in determining the structure, motion and function of a wide range of biological molecules. This chapter presents a brief overview of electrostatic interactions in cellular systems with a particular focus on how computational tools can be used to investigate these types of interactions. PMID:17964951

  2. Expression transmission using exaggerated animation for Elfoid

    PubMed Central

    Hori, Maiya; Tsuruda, Yu; Yoshimura, Hiroki; Iwai, Yoshio

    2015-01-01

    We propose an expression transmission system using a cellular-phone-type teleoperated robot called Elfoid. Elfoid has a soft exterior that provides the look and feel of human skin, and is designed to transmit the speaker's presence to their communication partner using a camera and microphone. To transmit the speaker's presence, Elfoid sends not only the voice of the speaker but also the facial expression captured by the camera. In this research, facial expressions are recognized using a machine learning technique. Elfoid cannot, however, display facial expressions because of its compactness and a lack of sufficiently small actuator motors. To overcome this problem, facial expressions are displayed using Elfoid's head-mounted mobile projector. In an experiment, we built a prototype system and experimentally evaluated it's subjective usability. PMID:26347686

  3. Using the principle of entropy maximization to infer genetic interaction networks from gene expression patterns.

    PubMed

    Lezon, Timothy R; Banavar, Jayanth R; Cieplak, Marek; Maritan, Amos; Fedoroff, Nina V

    2006-12-12

    We describe a method based on the principle of entropy maximization to identify the gene interaction network with the highest probability of giving rise to experimentally observed transcript profiles. In its simplest form, the method yields the pairwise gene interaction network, but it can also be extended to deduce higher-order interactions. Analysis of microarray data from genes in Saccharomyces cerevisiae chemostat cultures exhibiting energy metabolic oscillations identifies a gene interaction network that reflects the intracellular communication pathways that adjust cellular metabolic activity and cell division to the limiting nutrient conditions that trigger metabolic oscillations. The success of the present approach in extracting meaningful genetic connections suggests that the maximum entropy principle is a useful concept for understanding living systems, as it is for other complex, nonequilibrium systems.

  4. 5G: The Convergence of Wireless Communications.

    PubMed

    Chávez-Santiago, Raúl; Szydełko, Michał; Kliks, Adrian; Foukalas, Fotis; Haddad, Yoram; Nolan, Keith E; Kelly, Mark Y; Masonta, Moshe T; Balasingham, Ilangko

    As the rollout of 4G mobile communication networks takes place, representatives of industry and academia have started to look into the technological developments toward the next generation (5G). Several research projects involving key international mobile network operators, infrastructure manufacturers, and academic institutions, have been launched recently to set the technological foundations of 5G. However, the architecture of future 5G systems, their performance, and mobile services to be provided have not been clearly defined. In this paper, we put forth the vision for 5G as the convergence of evolved versions of current cellular networks with other complementary radio access technologies. Therefore, 5G may not be a single radio access interface but rather a "network of networks". Evidently, the seamless integration of a variety of air interfaces, protocols, and frequency bands, requires paradigm shifts in the way networks cooperate and complement each other to deliver data rates of several Gigabits per second with end-to-end latency of a few milliseconds. We provide an overview of the key radio technologies that will play a key role in the realization of this vision for the next generation of mobile communication networks. We also introduce some of the research challenges that need to be addressed.

  5. An Underlay Communication Channel for 5G Cognitive Mesh Networks: Packet Design, Implementation, Analysis, and Experimental Results

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

    Tarek Haddadin; Stephen Andrew Laraway; Arslan Majid

    This paper proposes and presents the design and implementation of an underlay communication channel (UCC) for 5G cognitive mesh networks. The UCC builds its waveform based on filter bank multicarrier spread spectrum (FB-MCSS) signaling. The use of this novel spread spectrum signaling allows the device-to-device (D2D) user equipments (UEs) to communicate at a level well below noise temperature and hence, minimize taxation on macro-cell/small-cell base stations and their UEs in 5G wireless systems. Moreover, the use of filter banks allows us to avoid those portions of the spectrum that are in use by macro-cell and small-cell users. Hence, both D2D-to-cellularmore » and cellular-to-D2D interference will be very close to none. We propose a specific packet for UCC and develop algorithms for packet detection, timing acquisition and tracking, as well as channel estimation and equalization. We also present the detail of an implementation of the proposed transceiver on a software radio platform and compare our experimental results with those from a theoretical analysis of our packet detection algorithm.« less

  6. Propagating gene expression fronts in a one-dimensional coupled system of artificial cells

    NASA Astrophysics Data System (ADS)

    Tayar, Alexandra M.; Karzbrun, Eyal; Noireaux, Vincent; Bar-Ziv, Roy H.

    2015-12-01

    Living systems employ front propagation and spatiotemporal patterns encoded in biochemical reactions for communication, self-organization and computation. Emulating such dynamics in minimal systems is important for understanding physical principles in living cells and in vitro. Here, we report a one-dimensional array of DNA compartments in a silicon chip as a coupled system of artificial cells, offering the means to implement reaction-diffusion dynamics by integrated genetic circuits and chip geometry. Using a bistable circuit we programmed a front of protein synthesis propagating in the array as a cascade of signal amplification and short-range diffusion. The front velocity is maximal at a saddle-node bifurcation from a bistable regime with travelling fronts to a monostable regime that is spatially homogeneous. Near the bifurcation the system exhibits large variability between compartments, providing a possible mechanism for population diversity. This demonstrates that on-chip integrated gene circuits are dynamical systems driving spatiotemporal patterns, cellular variability and symmetry breaking.

  7. AMON: a wearable multiparameter medical monitoring and alert system.

    PubMed

    Anliker, Urs; Ward, Jamie A; Lukowicz, Paul; Tröster, Gerhard; Dolveck, François; Baer, Michel; Keita, Fatou; Schenker, Eran B; Catarsi, Fabrizio; Coluccini, Luca; Belardinelli, Andrea; Shklarski, Dror; Alon, Menachem; Hirt, Etienne; Schmid, Rolf; Vuskovic, Milica

    2004-12-01

    This paper describes an advanced care and alert portable telemedical monitor (AMON), a wearable medical monitoring and alert system targeting high-risk cardiac/respiratory patients. The system includes continuous collection and evaluation of multiple vital signs, intelligent multiparameter medical emergency detection, and a cellular connection to a medical center. By integrating the whole system in an unobtrusive, wrist-worn enclosure and applying aggressive low-power design techniques, continuous long-term monitoring can be performed without interfering with the patients' everyday activities and without restricting their mobility. In the first two and a half years of this EU IST sponsored project, the AMON consortium has designed, implemented, and tested the described wrist-worn device, a communication link, and a comprehensive medical center software package. The performance of the system has been validated by a medical study with a set of 33 subjects. The paper describes the main concepts behind the AMON system and presents details of the individual subsystems and solutions as well as the results of the medical validation.

  8. Teen driver cell phone blocker.

    DOT National Transportation Integrated Search

    2012-02-01

    This study was a randomized control intervention to measure the effectiveness of a cellular phone control device : that communicates with the vehicles of teen drivers to deny them access to their phone while driving for the : purpose of reducing dist...

  9. Communication between filamentous pathogens and plants at the biotrophic interface.

    PubMed

    Yi, Mihwa; Valent, Barbara

    2013-01-01

    Fungi and oomycetes that colonize living plant tissue form extensive interfaces with plant cells in which the cytoplasm of the microorganism is closely aligned with the host cytoplasm for an extended distance. In all cases, specialized biotrophic hyphae function to hijack host cellular processes across an interfacial zone consisting of a hyphal plasma membrane, a specialized interfacial matrix, and a plant-derived membrane. The interface is the site of active secretion by both players. This cross talk at the interface determines the winner in adversarial relationships and establishes the partnership in mutualistic relationships. Fungi and oomycetes secrete many specialized effector proteins for controlling the host, and they can stimulate remarkable cellular reorganization even in distant plant cells. Breakthroughs in live-cell imaging of fungal and oomycete encounter sites, including live-cell imaging of pathogens secreting fluorescently labeled effector proteins, have led to recent progress in understanding communication across the interface.

  10. [Learning and implicit memory: mechanisms and neuroplasticity].

    PubMed

    Machado, S; Portella, C E; Silva, J G; Velasques, B; Bastos, V H; Cunha, M; Basile, L; Cagy, M; Piedade, R A; Ribeiro, P

    Learning and memory are complex processes that researchers have been attempting to unravel for over a century in order to gain a clear view of the underlying mechanisms. To review the basic cellular and molecular mechanisms involved in the process of procedural retention, to offer an overall view of the fundamental mechanisms involved in storing information by means of theories and models of memory, and to discuss the different types of memory and the role played by the cerebellum as a modulator of procedural memory. Experimental results from recent decades have opened up new areas of study regarding the participation of the biochemical and cellular processes related to the consolidation of information in the nervous system. The neuronal circuits involved in acquiring and consolidating memory are still not fully understood and the exact location of memory in the nervous system remains unknown. A number of intrinsic and extrinsic factors interfere in these processes, such as molecular (long-term potentiation and depression) and cellular mechanisms, which respond to communication and transmission between nerve cells. There are also factors that have their origin in the outside environment, which use the association of events to bring about the formation of new memories or may divert the subject from his or her main focus. Memory is not a singular occurrence; it is sub-divided into declarative and non-declarative or, when talking about the time it lasts, into short and long-term memory. Moreover, given its relation with neuronal mechanisms of learning, memory cannot be said to constitute an isolated process.

  11. Sensible Success

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Commercial remote sensing uses satellite imagery to provide valuable information about the planet's features. By capturing light reflected from the Earth's surface with cameras or sensor systems, usually mounted on an orbiting satellite, data is obtained for business enterprises with an interest in land feature distribution. Remote sensing is practical when applied to large-area coverage, such as agricultural monitoring, regional mapping, environmental assessment, and infrastructure planning. For example, cellular service providers use satellite imagery to select the most ideal location for a communication tower. Crowsey Incorporated has the ability to use remote sensing capabilities to conduct spatial geographic visualizations and other remote-sensing services. Presently, the company has found a demand for these services in the area of litigation support. By using spatial information and analyses, Crowsey helps litigators understand and visualize complex issues and then to communicate a clear argument, with complete indisputable evidence. Crowsey Incorporated is a proud partner in NASA's Mississippi Space Commerce Initiative, with research offices at the John C. Stennis Space Center.

  12. WiFi RFID demonstration for resource tracking in a statewide disaster drill.

    PubMed

    Cole, Stacey L; Siddiqui, Javeed; Harry, David J; Sandrock, Christian E

    2011-01-01

    To investigate the capabilities of Radio Frequency Identification (RFID) tracking of patients and medical equipment during a simulated disaster response scenario. RFID infrastructure was deployed at two small rural hospitals, in one large academic medical center and in two vehicles. Several item types from the mutual aid equipment list were selected for tracking during the demonstration. A central database server was installed at the UC Davis Medical Center (UCDMC) that collected RFID information from all constituent sites. The system was tested during a statewide disaster drill. During the drill, volunteers at UCDMC were selected to locate assets using the traditional method of locating resources and then using the RFID system. This study demonstrated the effectiveness of RFID infrastructure in real-time resource identification and tracking. Volunteers at UCDMC were able to locate assets substantially faster using RFID, demonstrating that real-time geolocation can be substantially more efficient and accurate than traditional manual methods. A mobile, Global Positioning System (GPS)-enabled RFID system was installed in a pediatric ambulance and connected to the central RFID database via secure cellular communication. This system is unique in that it provides for seamless region-wide tracking that adaptively uses and seamlessly integrates both outdoor cellular-based mobile tracking and indoor WiFi-based tracking. RFID tracking can provide a real-time picture of the medical situation across medical facilities and other critical locations, leading to a more coordinated deployment of resources. The RFID system deployed during this study demonstrated the potential to improve the ability to locate and track victims, healthcare professionals, and medical equipment during a region-wide disaster.

  13. Mitochondrial quality control and communications with the nucleus are important in maintaining mitochondrial function and cell health☆☆☆

    PubMed Central

    Kotiadis, Vassilios N.; Duchen, Michael R.; Osellame, Laura D.

    2014-01-01

    Background The maintenance of cell metabolism and homeostasis is a fundamental characteristic of living organisms. In eukaryotes, mitochondria are the cornerstone of these life supporting processes, playing leading roles in a host of core cellular functions, including energy transduction, metabolic and calcium signalling, and supporting roles in a number of biosynthetic pathways. The possession of a discrete mitochondrial genome dictates that the maintenance of mitochondrial ‘fitness’ requires quality control mechanisms which involve close communication with the nucleus. Scope of review This review explores the synergistic mechanisms that control mitochondrial quality and function and ensure cellular bioenergetic homeostasis. These include antioxidant defence mechanisms that protect against oxidative damage caused by reactive oxygen species, while regulating signals transduced through such free radicals. Protein homeostasis controls import, folding, and degradation of proteins underpinned by mechanisms that regulate bioenergetic capacity through the mitochondrial unfolded protein response. Autophagic machinery is recruited for mitochondrial turnover through the process of mitophagy. Mitochondria also communicate with the nucleus to exact specific transcriptional responses through retrograde signalling pathways. Major conclusions The outcome of mitochondrial quality control is not only reliant on the efficient operation of the core homeostatic mechanisms but also in the effective interaction of mitochondria with other cellular components, namely the nucleus. General significance Understanding mitochondrial quality control and the interactions between the organelle and the nucleus will be crucial in developing therapies for the plethora of diseases in which the pathophysiology is determined by mitochondrial dysfunction. This article is part of a Special Issue entitled Frontiers of Mitochondrial Research. PMID:24211250

  14. Dissecting Nck/Dock signaling pathways in Drosophila visual system.

    PubMed

    Rao, Yong

    2005-01-01

    The establishment of neuronal connections during embryonic development requires the precise guidance and targeting of the neuronal growth cone, an expanded cellular structure at the leading tip of a growing axon. The growth cone contains sophisticated signaling systems that allow the rapid communication between guidance receptors and the actin cytoskeleton in generating directed motility. Previous studies demonstrated a specific role for the Nck/Dock SH2/SH3 adapter protein in photoreceptor (R cell) axon guidance and target recognition in the Drosophila visual system, suggesting strongly that Nck/Dock is one of the long-sought missing links between cell surface receptors and the actin cytoskeleton. In this review, I discuss the recent progress on dissecting the Nck/Dock signaling pathways in R-cell growth cones. These studies have identified additional key components of the Nck/Dock signaling pathways for linking the receptor signaling to the remodeling of the actin cytoskeleton in controlling growth-cone motility.

  15. Dissecting Nck/Dock Signaling Pathways in Drosophila Visual System

    PubMed Central

    2005-01-01

    The establishment of neuronal connections during embryonic development requires the precise guidance and targeting of the neuronal growth cone, an expanded cellular structure at the leading tip of a growing axon. The growth cone contains sophisticated signaling systems that allow the rapid communication between guidance receptors and the actin cytoskeleton in generating directed motility. Previous studies demonstrated a specific role for the Nck/Dock SH2/SH3 adapter protein in photoreceptor (R cell) axon guidance and target recognition in the Drosophila visual system, suggesting strongly that Nck/Dock is one of the long-sought missing links between cell surface receptors and the actin cytoskeleton. In this review, I discuss the recent progress on dissecting the Nck/Dock signaling pathways in R-cell growth cones. These studies have identified additional key components of the Nck/Dock signaling pathways for linking the receptor signaling to the remodeling of the actin cytoskeleton in controlling growth-cone motility. PMID:15951852

  16. Bio-Inspired Networking — Self-Organizing Networked Embedded Systems

    NASA Astrophysics Data System (ADS)

    Dressler, Falko

    The turn to nature has brought us many unforeseen great concepts and solutions. This course seems to hold on for many research domains. In this article, we study the applicability of biological mechanisms and techniques in the domain of communications. In particular, we study the behavior and the challenges in networked embedded systems that are meant to self-organize in large groups of nodes. Application examples include wireless sensor networks and sensor/actuator networks. Based on a review of the needs and requirements in such networks, we study selected bio-inspired networking approaches that claim to outperform other methods in specific domains. We study mechanisms in swarm intelligence, the artificial immune system, and approaches based on investigations on the cellular signaling pathways. As a major conclusion, we derive that bio-inspired networking techniques do have advantages compared to engineering methods. Nevertheless, selection and employment must be done carefully to achieve the desired performance gains.

  17. Strategies for reducing driver distraction from in-vehicle telematics devices : a discussion document

    DOT National Transportation Integrated Search

    2003-04-01

    "In-Vehicle Telematics" refers to devices incorporating wireless communications technologies in order to provide information services, vehicle automation and other functions. While cellular phones are currently the most common type of telematics devi...

  18. 47 CFR 22.948 - Partitioning and Disaggregation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Partitioning and Disaggregation. 22.948 Section 22.948 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.948 Partitioning and Disaggregation. (a) Eligibility...

  19. 47 CFR 22.951 - Minimum coverage requirement.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Minimum coverage requirement. 22.951 Section 22.951 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.951 Minimum coverage requirement. Applications for...

  20. Mitochondrial dynamics and the cell cycle

    USDA-ARS?s Scientific Manuscript database

    Nuclear-mitochondrial (NM) communication impacts many aspects of plant development including vigor, sterility and viability. Dynamic changes in mitochondrial number, shape, size, and cellular location takes place during the cell cycle possibly impacting the process itself and leading to distribution...

  1. Technical Note: Novel method for water vapour monitoring using wireless communication networks measurements

    NASA Astrophysics Data System (ADS)

    David, N.; Alpert, P.; Messer, H.

    2009-04-01

    We propose a new technique that overcomes the obstacles of the existing methods for monitoring near-surface water vapour, by estimating humidity from data collected through existing wireless communication networks. Weather conditions and atmospheric phenomena affect the electromagnetic channel, causing attenuations to the radio signals. Thus, wireless communication networks are in effect built-in environmental monitoring facilities. The wireless microwave links, used in these networks, are widely deployed by cellular providers for backhaul communication between base stations, a few tens of meters above ground level. As a result, if all available measurements are used, the proposed method can provide moisture observations with high spatial resolution and potentially high temporal resolution. Further, the implementation cost is minimal, since the data used are already collected and saved by the cellular operators. In addition - many of these links are installed in areas where access is difficult such as orographic terrain and complex topography. As such, our method enables measurements in places that have been hard to measure in the past, or have never been measured before. The technique is restricted to weather conditions which exclude rain, fog or clouds along the propagation path. Strong winds that may cause movement of the link transmitter or receiver (or both) may also interfere with the ability to conduct accurate measurements. We present results from real-data measurements taken from two microwave links used in a backhaul cellular network that show convincing correlation to surface station humidity measurements. The measurements were taken daily in two sites, one in northern Israel (28 measurements), the other in central Israel (29 measurements). The correlation between the microwave link measurements and the humidity gauges were 0.9 and 0.82 for the north and central sites, respectively. The Root Mean Square Differences (RMSD) were 1.8 g/m3 and 3.4 g/m3 for the northern and central site measurements, respectively.

  2. Biological indicators in response to radiofrequency/microwave exposure.

    PubMed

    Marjanović, Ana Marija; Pavičić, Ivan; Trošić, Ivančica

    2012-09-01

    Over the years, due to rapid technological progress, radiation from man-made sources exceeded that of natural origin. There is a general concern regarding a growing number of appliances that use radiofrequency/ microwave (RF/MW) radiation with particular emphasis on mobile communication systems. Since nonthermal biological effects and mechanisms of RF/MW radiation are still uncertain, laboratory studies on animal models, tissues, cells, and cell free system are of extraordinary importance in bioelectromagnetic research. We believe that such investigations play a supporting role in public risk assessment. Cellular systems with the potential for a clear response to RF/MW exposures should be used in those studies. It is known that organism is a complex electrochemical system where processes of oxidation and reduction regularly occur. One of the plausible mechanisms is connected with generation of reactive oxygen species (ROS). Depending on concentration, ROS can have both beneficial and deleterious effects. Positive effects are connected with cell signalling, defence against infectious agents, and proliferative cell ability. On the other hand, excessive production, which overloads antioxidant defence mechanism, leads to cellular damage with serious potential for disease development. ROS concentration increase within the cell caused by RF/MW radiation seems to be a biologically relevant hypothesis to give clear insight into the RF/MW action at non-thermal level of radiation. In order to better understand the exact mechanism of action and its consequences, further research is needed in the field. We would like to present current knowledge on possible biological mechanisms of RF/MW actions.

  3. A Reinforcement Sensor Embedded Vertical Handoff Controller for Vehicular Heterogeneous Wireless Networks

    PubMed Central

    Li, Limin; Xu, Yubin; Soong, Boon-Hee; Ma, Lin

    2013-01-01

    Vehicular communication platforms that provide real-time access to wireless networks have drawn more and more attention in recent years. IEEE 802.11p is the main radio access technology that supports communication for high mobility terminals, however, due to its limited coverage, IEEE 802.11p is usually deployed by coupling with cellular networks to achieve seamless mobility. In a heterogeneous cellular/802.11p network, vehicular communication is characterized by its short time span in association with a wireless local area network (WLAN). Moreover, for the media access control (MAC) scheme used for WLAN, the network throughput dramatically decreases with increasing user quantity. In response to these compelling problems, we propose a reinforcement sensor (RFS) embedded vertical handoff control strategy to support mobility management. The RFS has online learning capability and can provide optimal handoff decisions in an adaptive fashion without prior knowledge. The algorithm integrates considerations including vehicular mobility, traffic load, handoff latency, and network status. Simulation results verify that the proposed algorithm can adaptively adjust the handoff strategy, allowing users to stay connected to the best network. Furthermore, the algorithm can ensure that RSUs are adequate, thereby guaranteeing a high quality user experience. PMID:24193101

  4. Short Communication: HIV Patient Systemic Mitochondrial Respiration Improves with Exercise.

    PubMed

    Kocher, Morgan; McDermott, Mindy; Lindsey, Rachel; Shikuma, Cecilia M; Gerschenson, Mariana; Chow, Dominic C; Kohorn, Lindsay B; Hetzler, Ronald K; Kimura, Iris F

    2017-10-01

    In HIV-infected individuals, impaired mitochondrial function may contribute to cardiometabolic disease as well as to fatigue and frailty. Aerobic exercise improves total body energy reserves; however, its impact at the cellular level is unknown. We assessed alterations in cellular bioenergetics in peripheral blood mononuclear cells (PBMC) before and after a 12-week aerobic exercise study in sedentary HIV-infected subjects on stable antiretroviral therapy who successfully completed a 12-week aerobic exercise program. In this prospective study, participants underwent supervised 20-40 min of light aerobic exercise (walking or jogging) performed three times per week for 12 weeks, gradually increasing to maintain an intensity of 50%-80% of heart rate reserve. Maximal aerobic capacity (VO 2MAX ) was assessed by a graded exercise test on a cycle ergometer before and after completion of the study. PBMC from compliant subjects (attended at least 70% of exercise sessions) were assessed for mitochondrial respiration using the Seahorse XF24 Bio-Analyzer. Seven of 24 enrolled subjects were compliant with the exercise regimen. In these individuals, a significant increase (p = .04) in VO 2MAX over 12 weeks was found with a median increase of 14%. During the same interval, a 2.45-fold increase in PBMC mitochondrial respiratory capacity (p = .04), a 5.65-fold increase in spare respiratory capacity (p = .01), and a 3.15-fold (p = .04) increase in nonmitochondrial respiration was observed. Aerobic exercise improves respiration at the cellular level. The diagnostic and prognostic value of such improved cellular respiration in the setting of chronic HIV warrants further investigation.

  5. A Low Cost Single Chip VDL Compatible Transceiver ASIC

    NASA Technical Reports Server (NTRS)

    Becker, Robert

    2004-01-01

    Recent trends in commercial communications system components have focussed almost exclusively on cellular telephone technology. As many of the traditional sources of receiver components have discontinued non-cellular telephone products, the designers of avionics and other low volume radio applications find themselves increasingly unable to find highly integrated components. This is particularly true for low power, low cost applications which cannot afford the lavish current consumption of the software defined radio approach increasingly taken by certified device manufacturers. In this paper, we describe a low power transceiver chip targeting applications from low VHF to low UHF frequencies typical of avionics systems. The chip encompasses a selectable single or double conversion design for the receiver and a low power IF upconversion transmitter. All local oscillators are synthesized and integrated into the chip. An on-chip I-Q modulator and demodulator provide baseband modulation and demodulation capability allowing the use of low power, fixed point signal processing components for signal demodulation. The goal of this program is to demonstrate a low cost VDL mode-3 transceiver using this chip to receive text weather information sent using 4-slot TDMA with no support for voice. The data will be sent from an experimental ground station. This work is funded by NASA Glenn Research Center.

  6. Self-organizing feature maps for dynamic control of radio resources in CDMA microcellular networks

    NASA Astrophysics Data System (ADS)

    Hortos, William S.

    1998-03-01

    The application of artificial neural networks to the channel assignment problem for cellular code-division multiple access (CDMA) cellular networks has previously been investigated. CDMA takes advantage of voice activity and spatial isolation because its capacity is only interference limited, unlike time-division multiple access (TDMA) and frequency-division multiple access (FDMA) where capacities are bandwidth-limited. Any reduction in interference in CDMA translates linearly into increased capacity. To satisfy the high demands for new services and improved connectivity for mobile communications, microcellular and picocellular systems are being introduced. For these systems, there is a need to develop robust and efficient management procedures for the allocation of power and spectrum to maximize radio capacity. Topology-conserving mappings play an important role in the biological processing of sensory inputs. The same principles underlying Kohonen's self-organizing feature maps (SOFMs) are applied to the adaptive control of radio resources to minimize interference, hence, maximize capacity in direct-sequence (DS) CDMA networks. The approach based on SOFMs is applied to some published examples of both theoretical and empirical models of DS/CDMA microcellular networks in metropolitan areas. The results of the approach for these examples are informally compared to the performance of algorithms, based on Hopfield- Tank neural networks and on genetic algorithms, for the channel assignment problem.

  7. Congestion and communication in confined ant traffic

    NASA Astrophysics Data System (ADS)

    Gravish, Nick; Gold, Gregory; Zangwill, Andrew; Goodisman, Michael A. D.; Goldman, Daniel I.

    2014-03-01

    Many social animals move and communicate within confined spaces. In subterranean fire ants Solenopsis invicta, mobility within crowded nest tunnels is important for resource and information transport. Within confined tunnels, communication and traffic flow are at odds: trafficking ants communicate through tactile interactions while stopped, yet ants that stop to communicate impose physical obstacles on the traffic. We monitor the bi-directional flow of fire ant workers in laboratory tunnels of varied diameter D. The persistence time of communicating ant aggregations, τ, increases approximately linearly with the number of participating ants, n. The sensitivity of traffic flow increases as D decreases and diverges at a minimum diameter, Dc. A cellular automata model incorporating minimal traffic features--excluded volume and communication duration--reproduces features of the experiment. From the model we identify a competition between information transfer and the need to maintain jam-free traffic flow. We show that by balancing information transfer and traffic flow demands, an optimum group strategy exists which maximizes information throughput. We acknowledge funding from NSF PoLS #0957659 and #PHY-1205878.

  8. Wireless technology in the ICU: boon or ban?

    PubMed Central

    Gladman, Aviv S; Lapinsky, Stephen E

    2007-01-01

    Wireless communication and data transmission are playing an increasing role in the critical care environment. Early anecdotal reports of electromagnetic interference (EMI) with intensive care unit (ICU) equipment resulted in many institutions banning these devices. An increasing literature database has more clearly defined the risks of EMI. Restrictions to the use of mobile devices are being lifted, and it has been suggested that the benefits of improved communication may outweigh the small risks. However, increased use of cellular phones and ever changing communication technologies require ongoing vigilance by healthcare device manufacturers, hospitals and device users, to prevent potentially hazardous events due to EMI. PMID:17875225

  9. Alaska Seismic Network Upgrade and Expansion

    NASA Astrophysics Data System (ADS)

    Sandru, J. M.; Hansen, R. A.; Estes, S. A.; Fowler, M.

    2009-12-01

    AEIC (Alaska Earthquake Information Center) has begun the task of upgrading the older regional seismic monitoring sites that have been in place for a number of years. Many of the original sites (some dating to the 1960's) are still single component analog technology. This was a very reasonable and ultra low power reliable system for its day. However with the advanced needs of today's research community, AEIC has begun upgrading to Broadband and Strong Motion Seismometers, 24 bit digitizers and high-speed two-way communications, while still trying to maintain the utmost reliability and maintaining low power consumption. Many sites have been upgraded or will be upgraded from single component to triaxial broad bands and triaxial accerometers. This provided much greater dynamic range over the older antiquated technology. The challenge is compounded by rapidly changing digital technology. Digitizersand data communications based on analog phone lines utilizing 9600 baud modems and RS232 are becoming increasingly difficult to maintain and increasingly expensive compared to current methods that use Ethernet, TCP/IP and UDP connections. Gaining a reliable Internet connection can be as easy as calling up an ISP and having a DSL connection installed or may require installing our own satellite uplink, where other options don't exist. LANs are accomplished with a variety of communications devices such as spread spectrum 900 MHz radios or VHF radios for long troublesome shots. WANs are accomplished with a much wider variety of equipment. Traditional analog phone lines are being used in some instances, however 56K lines are much more desirable. Cellular data links have become a convenient option in semiurban environments where digital cellular coverage is available. Alaska is slightly behind the curve on cellular technology due to its low population density and vast unpopulated areas but has emerged into this new technology in the last few years. Partnerships with organizations such as ANSS, Alaska Volcano Observatory, Bradley Lake Dam, Red Dog Mine, The Plate Boundary Observatory (PBO), Alaska Tsunami Warning Center, and City and State Emergency Managers has helped link vast networks together so that the overall data transition can be varied. This lessens the likelihood of having a single point of failure for an entire network. Robust communication is key to retrieving seismic data. AEIC has gone through growing pains learning how to harden our network and encompassing the many types of telemetry that can be utilized in today's world. Redundant telemetry paths are a goal that is key to retrieving data, however at times this is not feasible with the vast size and terrain in Alaska. We will demonstrate what has worked for us and what our network consists of.

  10. Recent advances in environmental monitoring using commercial microwave links

    NASA Astrophysics Data System (ADS)

    Alpert, Pinhas; David, Noam; Messer-Yaron, Hagit; Samuels, Rana

    2013-04-01

    The propagation of electromagnetic radiation in the lower atmosphere, at centimeter wavelengths, is impaired by atmospheric conditions. Absorption and scattering of the radiation, at frequencies of tens of GHz, are directly related to the atmospheric phenomena, primarily precipitation, oxygen, mist, fog and water vapor. As we have recently shown, commercial wireless communication networks supply high resolution precipitation measurements at ground level while often being situated in flood prone areas, covering large parts of these hazardous regions. On the other hand, at present, there are no satisfactory real time flash flood warning facilities found to cope well with this phenomenon. I will exemplify the flash flood warning potential of the commercial wireless communication system for two different semi-arid region cases when floods occurred in the Judean desert and in the northern Negev in Israel. In addition, I will review our recent improvements in monitoring rainfall as well as other-than-rain phenomena like, atmospheric moisture. Special focus on fog monitoring potential will be discussed. This research was supported by THE ISRAEL SCIENCE FOUNDATION (grant No. 173/08) and the PROCEMA VI coordinated by H. Kunstmann. The research was also supported by the by the United States- Israel BINATIONAL SCIENCE FOUNDATION (BSF, Grant No. 2010342). References: N. David, P. Alpert, and H. Messer, "Technical Note: Novel method for water vapour monitoring using wireless communication networks measurements", Atmos. Chem. Phys., 9, 2413-2418, 2009. A. Rayitsfeld, R. Samuels, A. Zinevich, U. Hadar and P. Alpert,"Comparison of two methodologies for long term rainfall monitoring using a commercial microwave communication system", Atmospheric Research 104-105, 119-127, 2012. N. David, P. Alpert, and H. Messer, "Novel method for fog monitoring using cellular networks infrastructures", Atmos. Meas. Tech. Discuss, 5, 5725-5752, 2012.

  11. 77 FR 67379 - Draft Guidance for Industry and Food and Drug Administration Staff; Highly Multiplexed...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-09

    ... approaches. The document does not apply to devices that are intended to screen donors of blood and blood components, and donors of human cells, tissues, and cellular and tissue-based products for communicable...

  12. 47 CFR 22.961-22.967 - [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false [Reserved] 22.961-22.967 Section 22.961-22.967 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service §§ 22.961-22.967 [Reserved] ...

  13. 47 CFR 22.912 - Service area boundary extensions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Service area boundary extensions. 22.912 Section 22.912 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.912 Service area boundary extensions. This...

  14. 47 CFR 22.973 - Information exchange.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Information exchange. 22.973 Section 22.973 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.973 Information exchange. (a) Prior notification. Public safety/CII...

  15. 47 CFR 22.927 - Responsibility for mobile stations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Responsibility for mobile stations. 22.927 Section 22.927 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.927 Responsibility for mobile stations...

  16. 47 CFR 22.927 - Responsibility for mobile stations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Responsibility for mobile stations. 22.927 Section 22.927 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.927 Responsibility for mobile stations...

  17. 47 CFR 22.912 - Service area boundary extensions.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Service area boundary extensions. 22.912 Section 22.912 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.912 Service area boundary extensions. This...

  18. 47 CFR 22.912 - Service area boundary extensions.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Service area boundary extensions. 22.912 Section 22.912 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.912 Service area boundary extensions. This...

  19. Multivalent ligand-receptor-mediated interaction of small filled vesicles with a cellular membrane

    NASA Astrophysics Data System (ADS)

    Zhdanov, Vladimir P.

    2017-07-01

    The ligand-receptor-mediated contacts of small sub-100-nm-sized lipid vesicles (or nanoparticles) with the cellular membrane are of interest in the contexts of cell-to-cell communication, endocytosis of membrane-coated virions, and drug (RNA) delivery. In all these cases, the interior of vesicles is filled by biologically relevant content. Despite the diversity of such systems, the corresponding ligand-receptor interaction possesses universal features. One of them is that the vesicle-membrane contacts can be accompanied by the redistribution of ligands and receptors between the contact and contact-free regions. In particular, the concentrations of ligands and receptors may become appreciably higher in the contact regions and their composition may there be different compared to that in the suspended state in the solution. A statistical model presented herein describes the corresponding distribution of various ligands and receptors and allows one to calculate the related change of the free energy with variation of the vesicle-engulfment extent. The results obtained are used to clarify the necessary conditions for the vesicle-assisted pathway of drug delivery.

  20. Efferocytosis and Outside-In Signaling by Cardiac Phagocytes. Links to Repair, Cellular Programming, and Intercellular Crosstalk in Heart

    PubMed Central

    DeBerge, Matthew; Zhang, Shuang; Glinton, Kristofor; Grigoryeva, Luba; Hussein, Islam; Vorovich, Esther; Ho, Karen; Luo, Xunrong; Thorp, Edward B.

    2017-01-01

    Phagocytic sensing and engulfment of dying cells and extracellular bodies initiate an intracellular signaling cascade within the phagocyte that can polarize cellular function and promote communication with neighboring non-phagocytes. Accumulating evidence links phagocytic signaling in the heart to cardiac development, adult myocardial homeostasis, and the resolution of cardiac inflammation of infectious, ischemic, and aging-associated etiology. Phagocytic clearance in the heart may be carried out by professional phagocytes, such as macrophages, and non-professional cells, including myofibrolasts and potentially epithelial cells. During cardiac development, phagocytosis initiates growth cues for early cardiac morphogenesis. In diseases of aging, including myocardial infarction, heightened levels of cell death require efficient phagocytic debridement to salvage further loss of terminally differentiated adult cardiomyocytes. Additional risk factors, including insulin resistance and other systemic risk factors, contribute to inefficient phagocytosis, altered phagocytic signaling, and delayed cardiac inflammation resolution. Under such conditions, inflammatory presentation of myocardial antigen may lead to autoimmunity and even possible rejection of transplanted heart allografts. Increased understanding of these basic mechanisms offers therapeutic opportunities. PMID:29163503

  1. Reliable Breakdown Obtained in Silicon Carbide Rectifiers

    NASA Technical Reports Server (NTRS)

    Neudeck, Philip G.

    1997-01-01

    The High Temperature Integrated Electronics and Sensor (HTIES) Program at the NASA Lewis Research Center is currently developing silicon carbide (SiC) for use in harsh conditions where silicon, the semiconductor used in nearly all of today's electronics, cannot function. Silicon carbide's demonstrated ability to function under extreme high-temperature, high-power, and/or high-radiation conditions will enable significant improvements to a far-ranging variety of applications and systems. These range from improved high-voltage switching for energy savings in public electric power distribution and electric vehicles, to more powerful microwave electronics for radar and cellular communications, to sensor and controls for cleaner-burning, more fuel-efficient jet aircraft and automobile engines.

  2. Using the principle of entropy maximization to infer genetic interaction networks from gene expression patterns

    PubMed Central

    Lezon, Timothy R.; Banavar, Jayanth R.; Cieplak, Marek; Maritan, Amos; Fedoroff, Nina V.

    2006-01-01

    We describe a method based on the principle of entropy maximization to identify the gene interaction network with the highest probability of giving rise to experimentally observed transcript profiles. In its simplest form, the method yields the pairwise gene interaction network, but it can also be extended to deduce higher-order interactions. Analysis of microarray data from genes in Saccharomyces cerevisiae chemostat cultures exhibiting energy metabolic oscillations identifies a gene interaction network that reflects the intracellular communication pathways that adjust cellular metabolic activity and cell division to the limiting nutrient conditions that trigger metabolic oscillations. The success of the present approach in extracting meaningful genetic connections suggests that the maximum entropy principle is a useful concept for understanding living systems, as it is for other complex, nonequilibrium systems. PMID:17138668

  3. Enhanced cryopreservation of MSCs in microfluidic bioreactor by regulated shear flow

    PubMed Central

    Bissoyi, Akalabya; Bit, Arindam; Singh, Bikesh Kumar; Singh, Abhishek Kumar; Patra, Pradeep Kumar

    2016-01-01

    Cell-matrix systems can be stored for longer period of time by means of cryopreservation. Cell-matrix and cell-cell interaction has been found to be critical in a number of basic biological processes. Tissue structure maintenance, cell secretary activity, cellular migration, and cell-cell communication all exist because of the presence of cell interactions. This complex and co-ordinated interaction between cellular constituents, extracellular matrix and adjacent cells has been identified as a significant contributor in the overall co-ordination of tissue. The prime objective of this investigation is to evaluate the effects of shear-stress and cell-substrate interaction in successful recovery of adherent human mesenchymal-stem-cells (hMSCs). A customized microfluidic bioreactor has been used for the purpose. We have measured the changes in focal-point-adhesion (FPAs) by changing induced shear stress inside the bioreactor. The findings indicate that with increase in shear stress, FPAs increases between substrate and MSCs. Further, experimental results show that increased FPAs (4e-3 μbar) enhances the cellular survivability of adherent MSCs. Probably, for the first time involvement of focal point interaction in the outcome of cryopreservation of MSCs has been clarified, and it proved a potentially new approach for modification of cryopreservation protocol by up-regulating focal point of cells to improve its clinical application. PMID:27748463

  4. Recent advances in environmental monitoring using commercial microwave links

    NASA Astrophysics Data System (ADS)

    Alpert, Pinhas; Guez, Oded; Messer, Hagit; David, Noam; Harel, Oz; Eshel, Adam; Cohen, Ori

    2016-04-01

    Recent advances in environmental monitoring using commercial microwave links Pinhas Alpert, H. Messer, N. David, O. Guez, O. Cohen, O. Harel, A. Eshel Tel Aviv University, Israel The propagation of electromagnetic radiation in the lower atmosphere, at centimeter wavelengths, is impaired by atmospheric conditions. Absorption and scattering of the radiation, at frequencies of tens of GHz, are directly related to the atmospheric phenomena, primarily precipitation, oxygen, mist, fog and water vapor. As was recently shown, wireless communication networks supply high resolution precipitation measurements at ground level while often being situated in flood prone areas, covering large parts of these hazardous regions. On the other hand, at present, there are no satisfactory real time flash flood warning facilities found to cope well with this phenomenon. I will exemplify the flash flood warning potential of the commercial wireless communication system for semi-arid region cases when floods occurred in the Judean desert in Israel with comparison to hydrological measurements in the Dead Sea area. In addition, I will review our recent improvements in monitoring rainfall as well as other-than-rain phenomena like, fog, dew, atmospheric moisture. References: N. David, P. Alpert, and H. Messer, "Technical Note: Novel method for water vapor monitoring using wireless communication networks measurements", Atmos. Chem. Phys., 9, 2413-2418, 2009. A. Rayitsfeld, R. Samuels, A. Zinevich, U. Hadar and P. Alpert,"Comparison of two methodologies for long term rainfall monitoring using a commercial microwave communication system", Atmospheric Research 104-105, 119-127, 2012. N. David, O. Sendik, H. Messer and P. Alpert, "Cellular network infrastructure-the future of fog monitoring?" BAMS (Oct. issue), 1687-1698, 2015. O. Harel, David, N., Alpert, P. and Messer, H., "The potential of microwave communication networks to detect dew using the GLRT- experimental study", IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 2015.

  5. 47 CFR 22.949 - Unserved area licensing process.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Unserved area licensing process. 22.949 Section 22.949 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.949 Unserved area licensing process. This section...

  6. 47 CFR 22.907 - Coordination of channel usage.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Coordination of channel usage. 22.907 Section 22.907 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.907 Coordination of channel usage. Licensees in the...

  7. 47 CFR 22.900 - Scope.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Scope. 22.900 Section 22.900 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular... that apply generally to the Public Mobile Services. In case of conflict, however, the rules in this...

  8. 47 CFR 22.907 - Coordination of channel usage.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Coordination of channel usage. 22.907 Section 22.907 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.907 Coordination of channel usage. Licensees in the...

  9. 47 CFR 22.913 - Effective radiated power limits.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Effective radiated power limits. 22.913 Section 22.913 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.913 Effective radiated power limits. The effective...

  10. 47 CFR 22.900 - Scope.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Scope. 22.900 Section 22.900 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular... that apply generally to the Public Mobile Services. In case of conflict, however, the rules in this...

  11. 47 CFR 22.900 - Scope.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Scope. 22.900 Section 22.900 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular... that apply generally to the Public Mobile Services. In case of conflict, however, the rules in this...

  12. 47 CFR 22.913 - Effective radiated power limits.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Effective radiated power limits. 22.913 Section 22.913 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.913 Effective radiated power limits. The effective...

  13. 47 CFR 22.907 - Coordination of channel usage.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Coordination of channel usage. 22.907 Section 22.907 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.907 Coordination of channel usage. Licensees in the...

  14. Wireless Technician

    ERIC Educational Resources Information Center

    Tech Directions, 2011

    2011-01-01

    One of the hottest areas in technology is invisible. Wireless communications allow people to transmit voice messages, data, and other signals through the air without physically connecting senders to receivers with cables or wires. And the technology is spreading at lightning speed. Cellular phones, personal digital assistants, and wireless…

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

    Baker, J.; Modlin, C.W.; Frerking, C.J.

    HIPROTECT (pronounced High-protect) is a system designed to protect national archaeological and natural treasures from destruction by vandals or looters. The system is being developed jointly by the Lawrence Livermore National Laboratory and the University of California at Riverside under the DOD Legacy Resource Management Program. Thousands of archaeological sites are located on military bases and national park lands. Treasure hunters or vandals are pillaging and destroying these sites at will, since the sites are generally located in remote areas, unattended and unprotected. The HIPROTECT system is designed to detect trespassers at the protected sites and to alert park officialsmore » or military officials of intrusions. An array of sensors is used to detect trespassers. The sensors are triggered when a person or vehicle approaches the site. Alarm messages are transmitted to alert park officials or law enforcement officials by way of a cellular telephone link. A video and audio system is included to assist the officials in verifying that an intrusion has occurred and to allow two-way communication with the intruders.« less

  16. Small Talk: Cell-to-Cell Communication in Bacteria

    ScienceCinema

    Bassler, Bonnie [Princeton University, Princeton, New Jersey, United States

    2017-12-09

    Cell-cell communication in bacteria involves the production, release, and subsequent detection of chemical signaling molecules called autoinducers. This process, called quorum sensing, allows bacteria to regulate gene expression on a population-wide scale. Processes controlled by quorum sensing are usually ones that are unproductive when undertaken by an individual bacterium but become effective when undertaken by the group. For example, quorum sensing controls bioluminescence, secretion of virulence factors, biofilm formation, sporulation, and the exchange of DNA. Thus, quorum sensing is a mechanism that allows bacteria to function as multi-cellular organisms. Bacteria make, detect, and integrate information from multiple autoinducers, some of which are used exclusively for intra-species communication while others enable communication between species. Research is now focused on the development of therapies that interfere with quorum sensing to control bacterial virulence.

  17. Regulation of neuronal communication by G protein-coupled receptors.

    PubMed

    Huang, Yunhong; Thathiah, Amantha

    2015-06-22

    Neuronal communication plays an essential role in the propagation of information in the brain and requires a precisely orchestrated connectivity between neurons. Synaptic transmission is the mechanism through which neurons communicate with each other. It is a strictly regulated process which involves membrane depolarization, the cellular exocytosis machinery, neurotransmitter release from synaptic vesicles into the synaptic cleft, and the interaction between ion channels, G protein-coupled receptors (GPCRs), and downstream effector molecules. The focus of this review is to explore the role of GPCRs and G protein-signaling in neurotransmission, to highlight the function of GPCRs, which are localized in both presynaptic and postsynaptic membrane terminals, in regulation of intrasynaptic and intersynaptic communication, and to discuss the involvement of astrocytic GPCRs in the regulation of neuronal communication. Copyright © 2015 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

  18. Prohibitin 2: At a communications crossroads.

    PubMed

    Bavelloni, Alberto; Piazzi, Manuela; Raffini, Mirco; Faenza, Irene; Blalock, William L

    2015-04-01

    Prohibitins (PHBs) are a highly conserved class of proteins first discovered as inhibitors of cellular proliferation. Since then PHBs have been found to have a significant role in transcription, nuclear signaling, mitochondrial structural integrity, cell division, and cellular membrane metabolism, placing these proteins among the key regulators of pathologies such as cancer, neuromuscular degeneration, and other metabolic diseases. The human genome encodes two PHB proteins, prohibitin 1 (PHB1) and prohibitin 2 (PHB2), which function not only as a heterodimeric complex, but also independently. While many previous reviews have focused on the better characterized prohibitin, PHB1, this review focuses on PHB2 and new data concerning its cellular functions both in complex with PHB1 and independent of PHB1. © 2015 International Union of Biochemistry and Molecular Biology.

  19. [Danger of cellular telephones and their relay stations].

    PubMed

    Santini, R; Seigne, M; Bonhomme-Faivre, L

    2000-07-01

    Cellular phones and their base stations emit pulsed microwaves in the environment. Cellular phone users are exposed in the near field and, under this condition, a large part of the electromagnetic energy is absorbed by the head, leading to an increased brain temperature. The general population is exposed under far field conditions to an electromagnetic intensity depending on the distance from the base station, passive re-emitters, the number of communications maintained by the base station and their position in relation to antennae (in front of the antenna or behind). Biological effects have been reported, such as radiofrequency sickness, electroencephalographic and blood pressure changes and also cancer risks in humans and animals exposed to microwave irradiation. Some European countries (Italy, France, Belgium, etc.) have taken measures to protect their populations.

  20. Cellular automata simulation of topological effects on the dynamics of feed-forward motifs

    PubMed Central

    Apte, Advait A; Cain, John W; Bonchev, Danail G; Fong, Stephen S

    2008-01-01

    Background Feed-forward motifs are important functional modules in biological and other complex networks. The functionality of feed-forward motifs and other network motifs is largely dictated by the connectivity of the individual network components. While studies on the dynamics of motifs and networks are usually devoted to the temporal or spatial description of processes, this study focuses on the relationship between the specific architecture and the overall rate of the processes of the feed-forward family of motifs, including double and triple feed-forward loops. The search for the most efficient network architecture could be of particular interest for regulatory or signaling pathways in biology, as well as in computational and communication systems. Results Feed-forward motif dynamics were studied using cellular automata and compared with differential equation modeling. The number of cellular automata iterations needed for a 100% conversion of a substrate into a target product was used as an inverse measure of the transformation rate. Several basic topological patterns were identified that order the specific feed-forward constructions according to the rate of dynamics they enable. At the same number of network nodes and constant other parameters, the bi-parallel and tri-parallel motifs provide higher network efficacy than single feed-forward motifs. Additionally, a topological property of isodynamicity was identified for feed-forward motifs where different network architectures resulted in the same overall rate of the target production. Conclusion It was shown for classes of structural motifs with feed-forward architecture that network topology affects the overall rate of a process in a quantitatively predictable manner. These fundamental results can be used as a basis for simulating larger networks as combinations of smaller network modules with implications on studying synthetic gene circuits, small regulatory systems, and eventually dynamic whole-cell models. PMID:18304325

  1. Cellular Satellites: Joint Communications With Integrated Acquisition

    DTIC Science & Technology

    2015-04-01

    cellphone towers in space, providing smartphone-like service that keeps users connected while on the move and in challenging urban, jungle or mountainous... cellphone technology. The first satellite, MUOS-1, was launched from Cape Ca- naveral, Fla., in February 2012 aboard an Atlas rocket, and

  2. EFFECTS OF TRICHLOROETHYLENE AND ITS METABOLITES ON RODENT HEPATOCYTE INTERCELLULAR COMMUNICATION

    EPA Science Inventory

    Chronic exposure to trichloroethylene (TCE) results in hepatocellular cancer in mice but not rats. The induction of hepatic tumors by TCE appears to be mediated through nongenotoxic or tumor promotion mechanisms. One cellular effect exhibited by a number of nongentoxic carcinogen...

  3. Tiled architecture of a CNN-mostly IP system

    NASA Astrophysics Data System (ADS)

    Spaanenburg, Lambert; Malki, Suleyman

    2009-05-01

    Multi-core architectures have been popularized with the advent of the IBM CELL. On a finer grain the problems in scheduling multi-cores have already existed in the tiled architectures, such as the EPIC and Da Vinci. It is not easy to evaluate the performance of a schedule on such architecture as historical data are not available. One solution is to compile algorithms for which an optimal schedule is known by analysis. A typical example is an algorithm that is already defined in terms of many collaborating simple nodes, such as a Cellular Neural Network (CNN). A simple node with a local register stack together with a 'rotating wheel' internal communication mechanism has been proposed. Though the basic CNN allows for a tiled implementation of a tiled algorithm on a tiled structure, a practical CNN system will have to disturb this regularity by the additional need for arithmetical and logical operations. Arithmetic operations are needed for instance to accommodate for low-level image processing, while logical operations are needed to fork and merge different data streams without use of the external memory. It is found that the 'rotating wheel' internal communication mechanism still handles such mechanisms without the need for global control. Overall the CNN system provides for a practical network size as implemented on a FPGA, can be easily used as embedded IP and provides a clear benchmark for a multi-core compiler.

  4. Switching theory-based steganographic system for JPEG images

    NASA Astrophysics Data System (ADS)

    Cherukuri, Ravindranath C.; Agaian, Sos S.

    2007-04-01

    Cellular communications constitute a significant portion of the global telecommunications market. Therefore, the need for secured communication over a mobile platform has increased exponentially. Steganography is an art of hiding critical data into an innocuous signal, which provide answers to the above needs. The JPEG is one of commonly used format for storing and transmitting images on the web. In addition, the pictures captured using mobile cameras are in mostly in JPEG format. In this article, we introduce a switching theory based steganographic system for JPEG images which is applicable for mobile and computer platforms. The proposed algorithm uses the fact that energy distribution among the quantized AC coefficients varies from block to block and coefficient to coefficient. Existing approaches are effective with a part of these coefficients but when employed over all the coefficients they show there ineffectiveness. Therefore, we propose an approach that works each set of AC coefficients with different frame work thus enhancing the performance of the approach. The proposed system offers a high capacity and embedding efficiency simultaneously withstanding to simple statistical attacks. In addition, the embedded information could be retrieved without prior knowledge of the cover image. Based on simulation results, the proposed method demonstrates an improved embedding capacity over existing algorithms while maintaining a high embedding efficiency and preserving the statistics of the JPEG image after hiding information.

  5. The role of exosomes in hepatitis, liver cirrhosis and hepatocellular carcinoma.

    PubMed

    Shen, Jiliang; Huang, Chiung-Kuei; Yu, Hong; Shen, Bo; Zhang, Yaping; Liang, Yuelong; Li, Zheyong; Feng, Xu; Zhao, Jie; Duan, Lian; Cai, Xiujun

    2017-05-01

    Exosomes are small vesicles that were initially thought to be a mechanism for discarding unneeded membrane proteins from reticulocytes. Their mediation of intercellular communication appears to be associated with several biological functions. Current studies have shown that most mammalian cells undergo the process of exosome formation and utilize exosome-mediated cell communication. Exosomes contain various microRNAs, mRNAs and proteins. They have been reported to mediate multiple functions, such as antigen presentation, immune escape and tumour progression. This concise review highlights the findings regarding the roles of exosomes in liver diseases, particularly hepatitis B, hepatitis C, liver cirrhosis and hepatocellular carcinoma. However, further elucidation of the contributions of exosomes to intercellular information transmission is needed. The potential medical applications of exosomes in liver diseases seem practical and will depend on the ingenuity of future investigators and their insights into exosome-mediated biological processes. © 2016 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  6. Attenuation of endocrine-exocrine pancreatic communication in type 2 diabetes: pancreatic extracellular matrix ultrastructural abnormalities.

    PubMed

    Hayden, Melvin R; Patel, Kamlesh; Habibi, Javad; Gupta, Deepa; Tekwani, Seema S; Whaley-Connell, Adam; Sowers, James R

    2008-01-01

    Ultrastructural observations reveal a continuous interstitial matrix connection between the endocrine and exocrine pancreas, which is lost due to fibrosis in rodent models and humans with type 2 diabetes mellitus (T2DM). Widening of the islet-exocrine interface appears to result in loss of desmosomes and adherens junctions between islet and acinar cells and is associated with hypercellularity consisting of pericytes and inflammatory cells in T2DM pancreatic tissue. Organized fibrillar collagen was closely associated with pericytes, which are known to differentiate into myofibroblasts-pancreatic stellate cells. Of importance, some pericyte cellular processes traverse both the connecting islet-exocrine interface and the endoacinar interstitium of the exocrine pancreas. Loss of cellular paracrine communication and extracellular matrix remodeling fibrosis in young animal models and humans may result in a dysfunctional insulino-acinar-ductal-incretin gut hormone axis, resulting in pancreatic insufficiency and glucagon-like peptide deficiency, which are known to exist in prediabetes and overt T2DM in humans.

  7. Attenuation of Endocrine-Exocrine Pancreatic Communication in Type 2 Diabetes: Pancreatic Extracellular Matrix Ultrastructural Abnormalities

    PubMed Central

    Hayden, Melvin R; Patel, Kamlesh; Habibi, Javad; Gupta, Deepa; Tekwani, Seema S.; Whaley-Connell, Adam; Sowers, James R.

    2009-01-01

    Ultrastructural observations reveal a continuous interstitial matrix connection between the endocrine and exocrine pancreas, which is lost due to fibrosis in rodent models and humans with type 2 diabetes mellitus (T2DM). Widening of the islet exocrine interface (IEI) appears to result in loss of desmosomes and adherens junctions between islet and acinar cells and is associated with hypercellularity consisting of pericytes and inflammatory cells in T2DM pancreatic tissue. Organized fibrillar collagen was closely associated with pericytes, which are known to differentiate into myofibroblasts – pancreatic stellate cells. Importantly, some pericyte cellular processes traverse both the connecting IEI and the endoacinar interstitium of the exocrine pancreas. Loss of cellular paracrine communication and extracellular matrix remodeling fibrosis in young animal models and humans may result in a dysfunctional insulino-acinar-ductal – incretin gut hormone axis resulting in pancreatic insufficiency and glucagon like peptide deficiency known to exist in prediabetes and overt T2DM in humans. PMID:19040593

  8. A parallelized three-dimensional cellular automaton model for grain growth during additive manufacturing

    NASA Astrophysics Data System (ADS)

    Lian, Yanping; Lin, Stephen; Yan, Wentao; Liu, Wing Kam; Wagner, Gregory J.

    2018-05-01

    In this paper, a parallelized 3D cellular automaton computational model is developed to predict grain morphology for solidification of metal during the additive manufacturing process. Solidification phenomena are characterized by highly localized events, such as the nucleation and growth of multiple grains. As a result, parallelization requires careful treatment of load balancing between processors as well as interprocess communication in order to maintain a high parallel efficiency. We give a detailed summary of the formulation of the model, as well as a description of the communication strategies implemented to ensure parallel efficiency. Scaling tests on a representative problem with about half a billion cells demonstrate parallel efficiency of more than 80% on 8 processors and around 50% on 64; loss of efficiency is attributable to load imbalance due to near-surface grain nucleation in this test problem. The model is further demonstrated through an additive manufacturing simulation with resulting grain structures showing reasonable agreement with those observed in experiments.

  9. A parallelized three-dimensional cellular automaton model for grain growth during additive manufacturing

    NASA Astrophysics Data System (ADS)

    Lian, Yanping; Lin, Stephen; Yan, Wentao; Liu, Wing Kam; Wagner, Gregory J.

    2018-01-01

    In this paper, a parallelized 3D cellular automaton computational model is developed to predict grain morphology for solidification of metal during the additive manufacturing process. Solidification phenomena are characterized by highly localized events, such as the nucleation and growth of multiple grains. As a result, parallelization requires careful treatment of load balancing between processors as well as interprocess communication in order to maintain a high parallel efficiency. We give a detailed summary of the formulation of the model, as well as a description of the communication strategies implemented to ensure parallel efficiency. Scaling tests on a representative problem with about half a billion cells demonstrate parallel efficiency of more than 80% on 8 processors and around 50% on 64; loss of efficiency is attributable to load imbalance due to near-surface grain nucleation in this test problem. The model is further demonstrated through an additive manufacturing simulation with resulting grain structures showing reasonable agreement with those observed in experiments.

  10. Extracellular Vesicles, Tunneling Nanotubes, and Cellular Interplay: Synergies and Missing Links

    PubMed Central

    Nawaz, Muhammad; Fatima, Farah

    2017-01-01

    The process of intercellular communication seems to have been a highly conserved evolutionary process. Higher eukaryotes use several means of intercellular communication to address both the changing physiological demands of the body and to fight against diseases. In recent years, there has been an increasing interest in understanding how cell-derived nanovesicles, known as extracellular vesicles (EVs), can function as normal paracrine mediators of intercellular communication, but can also elicit disease progression and may be used for innovative therapies. Over the last decade, a large body of evidence has accumulated to show that cells use cytoplasmic extensions comprising open-ended channels called tunneling nanotubes (TNTs) to connect cells at a long distance and facilitate the exchange of cytoplasmic material. TNTs are a different means of communication to classical gap junctions or cell fusions; since they are characterized by long distance bridging that transfers cytoplasmic organelles and intracellular vesicles between cells and represent the process of heteroplasmy. The role of EVs in cell communication is relatively well-understood, but how TNTs fit into this process is just emerging. The aim of this review is to describe the relationship between TNTs and EVs, and to discuss the synergies between these two crucial processes in the context of normal cellular cross-talk, physiological roles, modulation of immune responses, development of diseases, and their combinatory effects in tissue repair. At the present time this review appears to be the first summary of the implications of the overlapping roles of TNTs and EVs. We believe that a better appreciation of these parallel processes will improve our understanding on how these nanoscale conduits can be utilized as novel tools for targeted therapies. PMID:28770210

  11. Improving communication in level 1 trauma centers: replacing pagers with smartphones.

    PubMed

    Joseph, Bellal; Pandit, Viraj; Khreiss, Mohammad; Aziz, Hassan; Kulvatunyou, Narong; Tang, Andrew; Wynne, Julie; O'Keeffe, Terence; Friese, Randall S; Weinstein, Ronald S; Rhee, Peter

    2013-03-01

    Communication among healthcare providers continues to change, and 90% of healthcare providers are now carrying cellular phones. Compared with pagers, the rate and amount of information immediately available via cellular phones are far superior. Wireless devices such as smartphones are ideal in acute trauma settings as they can transfer patient information quickly in a coordinate manner to all the team members responsible for patient care. A questionnaire survey was distributed among all the trauma surgeons, surgery residents, and nurse practitioners who were a part of the trauma surgery team at a Level 1 trauma center. Answers to each question were recorded on a 5-point Likert scale. The completed survey questionnaires were analyzed using Statistical Package for Social Sciences software (SPSS version 17; SPSS, Inc., Chicago, IL). The respondents had an overall positive experience with the usage of the third-generation (3G) smartphones, with 94% of respondents in favor of having wireless means of communication at a Level 1 trauma center. Of respondents, 78% found the device very user friendly, 98% stated that use of smartphones had improved the speed and quality of communication, 96% indicated that 3G smartphones were a useful teaching tool, 90% of the individuals felt there was improvement in the physician's response time to both routine and critical patients, and 88% of respondents were aware of the rules and regulations of the Health Insurance Portability and Accountability Act. Smartphones in an acute trauma setting are easy to use and improve the means of communication among the team members by providing accurate and reliable information in real time. Smartphones are effective in patient follow-up and as a teaching tool. Strict rules need to be used to govern the use of smartphones to secure the safety and secrecy of patient information.

  12. The noncoding human genome and the future of personalised medicine.

    PubMed

    Cowie, Philip; Hay, Elizabeth A; MacKenzie, Alasdair

    2015-01-30

    Non-coding cis-regulatory sequences act as the 'eyes' of the genome and their role is to perceive, organise and relay cellular communication information to RNA polymerase II at gene promoters. The evolution of these sequences, that include enhancers, silencers, insulators and promoters, has progressed in multicellular organisms to the extent that cis-regulatory sequences make up as much as 10% of the human genome. Parallel evidence suggests that 75% of polymorphisms associated with heritable disease occur within predicted cis-regulatory sequences that effectively alter the 'perception' of cis-regulatory sequences or render them blind to cell communication cues. Cis-regulatory sequences also act as major functional targets of epigenetic modification thus representing an important conduit through which changes in DNA-methylation affects disease susceptibility. The objectives of the current review are (1) to describe what has been learned about identifying and characterising cis-regulatory sequences since the sequencing of the human genome; (2) to discuss their role in interpreting cell signalling pathways pathways; and (3) outline how this role may be altered by polymorphisms and epigenetic changes. We argue that the importance of the cis-regulatory genome for the interpretation of cellular communication pathways cannot be overstated and understanding its role in health and disease will be critical for the future development of personalised medicine.

  13. Bacterial intelligence: imitation games, time-sharing, and long-range quantum coherence.

    PubMed

    Majumdar, Sarangam; Pal, Sukla

    2017-09-01

    Bacteria are far more intelligent than we can think of. They adopt different survival strategies to make their life comfortable. Researches on bacterial communication to date suggest that bacteria can communicate with each other using chemical signaling molecules as well as using ion channel mediated electrical signaling. Though in past few decades the scopes of chemical signaling have been investigated extensively, those of electrical signaling have received less attention. In this article, we present a novel perspective on time-sharing behavior, which maintains the biofilm growth under reduced nutrient supply between two distant biofilms through electrical signaling based on the experimental evidence reported by Liu et al., in 2017. In addition, following the recent work by Humphries et al. Cell 168(1):200-209, in 2017, we highlight the consequences of long range electrical signaling within biofilm communities through spatially propagating waves of potassium. Furthermore, we address the possibility of two-way cellular communication between artificial and natural cells through chemical signaling being inspired by recent experimental observation (Lentini et al. 2017) where the efficiency of artificial cells in imitating the natural cells is estimated through cellular Turing test. These three spectacular observations lead us to envisage and devise new classical and quantum views of these complex biochemical networks that have never been realized previously.

  14. Integration of mobile satellite and cellular systems

    NASA Technical Reports Server (NTRS)

    Drucker, Elliott H.; Estabrook, Polly; Pinck, Deborah; Ekroot, Laura

    1993-01-01

    By integrating the ground based infrastructure component of a mobile satellite system with the infrastructure systems of terrestrial 800 MHz cellular service providers, a seamless network of universal coverage can be established. Users equipped for both cellular and satellite service can take advantage of a number of features made possible by such integration, including seamless handoff and universal roaming. To provide maximum benefit at lowest posible cost, the means by which these systems are integrated must be carefully considered. Mobile satellite hub stations must be configured to efficiently interface with cellular Mobile Telephone Switching Offices (MTSO's), and cost effective mobile units that provide both cellular and satellite capability must be developed.

  15. Integration of mobile satellite and cellular systems

    NASA Astrophysics Data System (ADS)

    Drucker, Elliott H.; Estabrook, Polly; Pinck, Deborah; Ekroot, Laura

    By integrating the ground based infrastructure component of a mobile satellite system with the infrastructure systems of terrestrial 800 MHz cellular service providers, a seamless network of universal coverage can be established. Users equipped for both cellular and satellite service can take advantage of a number of features made possible by such integration, including seamless handoff and universal roaming. To provide maximum benefit at lowest posible cost, the means by which these systems are integrated must be carefully considered. Mobile satellite hub stations must be configured to efficiently interface with cellular Mobile Telephone Switching Offices (MTSO's), and cost effective mobile units that provide both cellular and satellite capability must be developed.

  16. Root Raised Cosine (RRC) Filters and Pulse Shaping in Communication Systems

    NASA Technical Reports Server (NTRS)

    Cubukcu, Erkin

    2012-01-01

    This presentation briefly discusses application of the Root Raised Cosine (RRC) pulse shaping in the space telecommunication. Use of the RRC filtering (i.e., pulse shaping) is adopted in commercial communications, such as cellular technology, and used extensively. However, its use in space communication is still relatively new. This will possibly change as the crowding of the frequency spectrum used in the space communication becomes a problem. The two conflicting requirements in telecommunication are the demand for high data rates per channel (or user) and need for more channels, i.e., more users. Theoretically as the channel bandwidth is increased to provide higher data rates the number of channels allocated in a fixed spectrum must be reduced. Tackling these two conflicting requirements at the same time led to the development of the RRC filters. More channels with wider bandwidth might be tightly packed in the frequency spectrum achieving the desired goals. A link model with the RRC filters has been developed and simulated. Using 90% power Bandwidth (BW) measurement definition showed that the RRC filtering might improve spectrum efficiency by more than 75%. Furthermore using the matching RRC filters both in the transmitter and receiver provides the improved Bit Error Rate (BER) performance. In this presentation the theory of three related concepts, namely pulse shaping, Inter Symbol Interference (ISI), and Bandwidth (BW) will be touched upon. Additionally the concept of the RRC filtering and some facts about the RRC filters will be presented

  17. Towards systems biology of the gravity response of higher plants -multiscale analysis of Arabidopsis thaliana root growth

    NASA Astrophysics Data System (ADS)

    Palme, Klaus; Aubry, D.; Bensch, M.; Schmidt, T.; Ronneberger, O.; Neu, C.; Li, X.; Wang, H.; Santos, F.; Wang, B.; Paponov, I.; Ditengou, F. A.; Teale, W. T.; Volkmann, D.; Baluska, F.; Nonis, A.; Trevisan, S.; Ruperti, B.; Dovzhenko, A.

    Gravity plays a fundamental role in plant growth and development. Up to now, little is known about the molecular organisation of the signal transduction cascades and networks which co-ordinate gravity perception and response. By using an integrated systems biological approach, a systems analysis of gravity perception and the subsequent tightly-regulated growth response is planned in the model plant Arabidopsis thaliana. This approach will address questions such as: (i) what are the components of gravity signal transduction pathways? (ii) what are the dynamics of these components? (iii) what is their spatio-temporal regulation in different tis-sues? Using Arabidopsis thaliana as a model-we use root growth to obtain insights in the gravity response. New techniques enable identification of the individual genes affected by grav-ity and further integration of transcriptomics and proteomics data into interaction networks and cell communication events that operate during gravitropic curvature. Using systematic multiscale analysis we have identified regulatory networks consisting of transcription factors, the protein degradation machinery, vesicle trafficking and cellular signalling during the gravire-sponse. We developed approach allowing to incorporate key features of the root system across all relevant spatial and temporal scales to describe gene-expression patterns and correlate them with individual gene and protein functions. Combination of high-resolution microscopy and novel computational tools resulted in development of the root 3D model in which quantitative descriptions of cellular network properties and of multicellular interactions important in root growth and gravitropism can be integrated for the first time.

  18. Using RF-DNA Fingerprints to Discriminate ZigBee Devices in an Operational Environment

    DTIC Science & Technology

    2013-03-01

    network keys and Media Access Control (MAC) lists which can be subverted through interception and spoofing using open-source hacking tools. This work...for Mobile Communication (GSM) cellular phones [40, 47], IEEE 802.11 WiFi [21, 23, 24, 28, 29, 35, 42], and IEEE 802.16 WiMAX [34, 35, 37, 38, 48...802.11a WiFi × [21, 28–30, 35, 48] GSM Cellular × [39, 40, 47] 802.16e WiMax × [34, 35, 38, 48] 802.15.4 ZigBee × [31] × [11, 12] Classifier Type MDA/ML

  19. Cellular Energetic Status Supervises the Synthesis of Bis-Diphosphoinositol Tetrakisphosphate Independently of AMP-Activated Protein Kinase

    PubMed Central

    Choi, Kuicheon; Mollapour, Elahe; Choi, Jae H.; Shears, Stephen B.

    2009-01-01

    Cells aggressively defend adenosine nucleotide homeostasis; intracellular biosensors detect variations in energetic status and communicate with other cellular networks to initiate adaptive responses. Here, we demonstrate some new elements of this communication process, and we show that this networking is compromised by off-target, bioenergetic effects of some popular pharmacological tools. Treatment of cells with 5-aminoimidazole-4-carboxamide ribonucleoside (AICAR), so as to simulate elevated AMP levels, reduced the synthesis of bis-diphosphoinositol tetrakisphosphate ([PP]2-InsP4), an intracellular signal that phosphorylates proteins in a kinase-independent reaction. This was a selective effect; levels of other inositol phosphates were unaffected by AICAR. By genetically manipulating cellular AMP-activated protein kinase activity, we showed that it did not mediate these effects of AICAR. Instead, we conclude that the simulation of deteriorating adenosine nucleotide balance itself inhibited [PP]2-InsP4 synthesis. This conclusion is consistent with our demonstrating that oligomycin elevated cellular [AMP] and selectively inhibited [PP]2-InsP4 synthesis without affecting other inositol phosphates. In addition, we report that the short-term increases in [PP]2-InsP4 levels normally seen during hyperosmotic stress were attenuated by 2-(2-chloro-4-iodophenylamino)-N-cyclopropylmethoxy-3,4-difluoro-benzamide (PD184352). The latter is typically considered an exquisitely specific mitogen-activated protein kinase kinase (MEK) inhibitor, but small interfering RNA against MEK or extracellular signal-regulated kinase revealed that this mitogen-activated protein kinase pathway was not involved. Instead, we demonstrate that [PP]2-InsP4 synthesis was inhibited by PD184352 through its nonspecific effects on cellular energy balance. Two other MEK inhibitors, 1,4-diamino-2,3-dicyano-1,4-bis(methylthio)butadiene (U0126) and 2′-amino-3′-methoxyflavone (PD98059), had similar off-target effects. We conclude that the levels and hence the signaling strength of [PP]2-InsP4 is supervised by cellular adenosine nucleotide balance, signifying a new link between signaling and bioenergetic networks. PMID:18460607

  20. Bone and Muscle: Interactions beyond Mechanical

    PubMed Central

    Brotto, Marco

    2015-01-01

    The musculoskeletal system is significantly more complex than portrayed by traditional reductionist approaches that have focused on and studied the components of this system separately. While bone and skeletal muscle are the two largest tissues within this system, this system also includes tendons, ligaments, cartilage, joints and other connective tissue along with vascular and nervous tissue. Because the main function of this system is locomotion, the mechanical interaction among the major players of this system is essential for the many shapes and forms observed in vertebrates and even in invertebrates. Thus, it is logical that the mechanical coupling theories of musculoskeletal development exert a dominant influence on our understanding of the biology of the musculoskeletal system, because these relationships are relatively easy to observe, measure, and perturb. Certainly much less recognized is the molecular and biochemical interaction among the individual players of the musculoskeletal system. In this brief review article, we first introduce some of the key reasons why the mechanical coupling theory has dominated our view of bone-muscle interactions followed by summarizing evidence for the secretory nature of bones and muscles. Finally, a number of highly physiological questions that cannot be answered by the mechanical theories alone will be raised along with different lines of evidence that support both a genetic and a biochemical communication between bones and muscles. It is hoped that these discussions will stimulate new insights into this fertile and promising new way of defining the relationships between these closely related tissues. Understanding the cellular and molecular mechanisms responsible for biochemical communication between bone and muscle is important not only from a basic research perspective but also as a means to identify potential new therapies for bone and muscle diseases, especially for when they co-exist. PMID:26453500

  1. Radio Frequency Based Programmable Logic Controller Anomaly Detection

    DTIC Science & Technology

    2013-09-01

    include wireless radios, IEEE 802.15 Blue- tooth devices, cellular phones, and IEEE 802.11 WiFi networking devices. While wireless communication...MacKenzie, H. Shamoon Malware and SCADA Security What are the Im- pacts? . Technical Report, Tofino Security, Sep 2012. 61. Mateti,P. Hacking Techniques

  2. Evaluation of "Autosense-III" laser detection technology for traffic applications on I-4

    DOT National Transportation Integrated Search

    2001-11-01

    The major tasks of this project include procuring the two AUTOSENSE III units; selecting a site on I-4 for installation of the units, installing the units successfully on I-4, establishing a remote communication link through cellular data line to dow...

  3. E-Professionalism for Early Care and Education Providers

    ERIC Educational Resources Information Center

    Harte, Helene Arbouet

    2011-01-01

    Teachers of young children work hard to be professional and to be viewed by others as professionals. These efforts to maintain professionalism must include e-professionalism. E-professionalism involves behavior related to professional standards and ethics when using electronic communication (Evans & Gerwitz, 2008). Cellular telephones, social…

  4. 47 CFR 22.921 - 911 call processing procedures; 911-only calling mode.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false 911 call processing procedures; 911-only calling mode. 22.921 Section 22.921 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.921 911 call processing...

  5. 47 CFR 22.921 - 911 call processing procedures; 911-only calling mode.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false 911 call processing procedures; 911-only calling mode. 22.921 Section 22.921 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.921 911 call processing...

  6. Implementing new technologies for public safety communication: competing frequency demands and standardization issues

    NASA Astrophysics Data System (ADS)

    Stevens, Kathryn J.

    1997-01-01

    Attempting to incorporate new technology into an existing environment is often very difficult. The problems are lengthy to resolve, wrought with confusion and seldom turn out like anyone expected. This document represents an overview of one such attempt. It outlines the general areas of concern which could be affected by a transition, and potential problems that may be encountered as a result of the effort. Over the past several decades, many local, state and federal agencies are pressing for more efficient use of frequency spectrums. The urgency of this issue has grown due to the demands of several groups wanting access to these channels for commercial use. Pager systems, cellular telephones, radio systems for private businesses all demand more space. Public safety agencies are starting to fear their needs will diminish in importance as the available channel spectrums are consumed by commercial ventures. How to share these channels, purchase appropriate equipment to meet your needs, and stay within a reasonable budget are not easy tasks. Public safety agencies who rely on communication networks in the performance of their jobs also know why encryption is important. Protecting the rights of citizens as police exchange information over the air, maintaining the integrity of an investigation and officer safety are all concerns police must address each time they use a radio.

  7. Supporting performance and configuration management of GTE cellular networks

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

    Tan, Ming; Lafond, C.; Jakobson, G.

    GTE Laboratories, in cooperation with GTE Mobilnet, has developed and deployed PERFFEX (PERFormance Expert), an intelligent system for performance and configuration management of cellular networks. PERFEX assists cellular network performance and radio engineers in the analysis of large volumes of cellular network performance and configuration data. It helps them locate and determine the probable causes of performance problems, and provides intelligent suggestions about how to correct them. The system combines an expert cellular network performance tuning capability with a map-based graphical user interface, data visualization programs, and a set of special cellular engineering tools. PERFEX is in daily use atmore » more than 25 GTE Mobile Switching Centers. Since the first deployment of the system in late 1993, PERFEX has become a major GTE cellular network performance optimization tool.« less

  8. The Physical Microbe; An introduction to noise, control, and communication in the prokaryotic cell

    NASA Astrophysics Data System (ADS)

    Hagen, Stephen J.

    2017-10-01

    Physical biology is a fusion of biology and physics. This book narrows down the scope of physical biology by focusing on the microbial cell; exploring the physical phenomena of noise, feedback, and variability that arise in the cellular information-processing circuits used by bacteria. It looks at the microbe from a physics perspective, asking how the cell optimizes its function to live within the constraints of physics. It introduces a physical and information-based (as opposed to microbiological) perspective on communication and signalling between microbes.

  9. The perception of strigolactones in vascular plants.

    PubMed

    Lumba, Shelley; Holbrook-Smith, Duncan; McCourt, Peter

    2017-05-17

    Small-molecule hormones play central roles in plant development, ranging from cellular differentiation and organ formation to developmental response instruction in changing environments. A recently discovered collection of related small molecules collectively called strigolactones are of particular interest, as these hormones also function as ecological communicators between plants and fungi and between parasitic plants and their hosts. Advances from model plant systems have begun to unravel how, as a hormone, strigolactone is perceived and transduced. In this Review, we summarize this information and examine how understanding strigolactone hormone signaling is leading to insights into parasitic plant infections. We specifically focus on how the development of chemical probes can be used in combination with model plant systems to dissect strigolactone's perception in the parasitic plant Striga hermonthica. This information is particularly relevant since Striga is considered one of the largest impediments to food security in sub-Saharan Africa.

  10. Evaluation of the traffic parameters in a metropolitan area by fusing visual perceptions and CNN processing of webcam images.

    PubMed

    Faro, Alberto; Giordano, Daniela; Spampinato, Concetto

    2008-06-01

    This paper proposes a traffic monitoring architecture based on a high-speed communication network whose nodes are equipped with fuzzy processors and cellular neural network (CNN) embedded systems. It implements a real-time mobility information system where visual human perceptions sent by people working on the territory and video-sequences of traffic taken from webcams are jointly processed to evaluate the fundamental traffic parameters for every street of a metropolitan area. This paper presents the whole methodology for data collection and analysis and compares the accuracy and the processing time of the proposed soft computing techniques with other existing algorithms. Moreover, this paper discusses when and why it is recommended to fuse the visual perceptions of the traffic with the automated measurements taken from the webcams to compute the maximum traveling time that is likely needed to reach any destination in the traffic network.

  11. Using exosomes, naturally-equipped nanocarriers, for drug delivery.

    PubMed

    Batrakova, Elena V; Kim, Myung Soo

    2015-12-10

    Exosomes offer distinct advantages that uniquely position them as highly effective drug carriers. Comprised of cellular membranes with multiple adhesive proteins on their surface, exosomes are known to specialize in cell-cell communications and provide an exclusive approach for the delivery of various therapeutic agents to target cells. In addition, exosomes can be amended through their parental cells to express a targeting moiety on their surface, or supplemented with desired biological activity. Development and validation of exosome-based drug delivery systems are the focus of this review. Different techniques of exosome isolation, characterization, drug loading, and applications in experimental disease models and clinic are discussed. Exosome-based drug formulations may be applied to a wide variety of disorders such as cancer, various infectious, cardiovascular, and neurodegenerative disorders. Overall, exosomes combine benefits of both synthetic nanocarriers and cell-mediated drug delivery systems while avoiding their limitations. Published by Elsevier B.V.

  12. Improving Situational Awareness for First Responders via Mobile Computing

    NASA Technical Reports Server (NTRS)

    Betts, Bradley J.; Mah, Robert W.; Papasin, Richard; Del Mundo, Rommel; McIntosh, Dawn M.; Jorgensen, Charles

    2005-01-01

    This project looks to improve first responder situational awareness using tools and techniques of mobile computing. The prototype system combines wireless communication, real-time location determination, digital imaging, and three-dimensional graphics. Responder locations are tracked in an outdoor environment via GPS and uploaded to a central server via GPRS or an 802.11 network. Responders can also wirelessly share digital images and text reports, both with other responders and with the incident commander. A pre-built three dimensional graphics model of a particular emergency scene is used to visualize responder and report locations. Responders have a choice of information end points, ranging from programmable cellular phones to tablet computers. The system also employs location-aware computing to make responders aware of particular hazards as they approach them. The prototype was developed in conjunction with the NASA Ames Disaster Assistance and Rescue Team and has undergone field testing during responder exercise at NASA Ames.

  13. Improving Situational Awareness for First Responders via Mobile Computing

    NASA Technical Reports Server (NTRS)

    Betts, Bradley J.; Mah, Robert W.; Papasin, Richard; Del Mundo, Rommel; McIntosh, Dawn M.; Jorgensen, Charles

    2006-01-01

    This project looks to improve first responder incident command, and an appropriately managed flow of situational awareness using mobile computing techniques. The prototype system combines wireless communication, real-time location determination, digital imaging, and three-dimensional graphics. Responder locations are tracked in an outdoor environment via GPS and uploaded to a central server via GPRS or an 802. II network. Responders can also wireless share digital images and text reports, both with other responders and with the incident commander. A pre-built three dimensional graphics model of the emergency scene is used to visualize responder and report locations. Responders have a choice of information end points, ranging from programmable cellular phones to tablet computers. The system also employs location-aware computing to make responders aware of particular hazards as they approach them. The prototype was developed in conjunction with the NASA Ames Disaster Assistance and Rescue Team and has undergone field testing during responder exercises at NASA Ames.

  14. An experiment to enable commercial mobile satellite service

    NASA Technical Reports Server (NTRS)

    Lovell, R. R.; Knouse, G. H.; Weber, W. J.

    1982-01-01

    A Mobile Satellite Experiment (MSAT-X) is described, based on a planned cooperative U.S./Canadian program. The experiment would establish network architecture, develop system and ground-segment technology, and define the technical characteristics needed to help structure the regulatory/institutional framework needed to enable a first-generation commercial satellite service. A satellite of this type would augment terrestrial systems, both cellular and noncellular, in the thin-route/rural areas of the country where service is either unavailable or inadequate. Applications range from wide-area radio/dispatch (e.g., oil exploration and interstate trucking) to extension of the public mobile telephone service. Market estimates are provided and experiment objectives and requirements are delineated. The requirements are being developed in close coordination with the Department of Communications (DOC) of Canada and with industry and potential-user organizations. The paper closes with a development plan and milestone chart.

  15. Towards oscillations-based simulation of social systems: a neurodynamic approach

    NASA Astrophysics Data System (ADS)

    Plikynas, Darius; Basinskas, Gytis; Laukaitis, Algirdas

    2015-04-01

    This multidisciplinary work presents synopsis of theories in the search for common field-like fundamental principles of self-organisation and communication existing on quantum, cellular, and even social levels. Based on these fundamental principles, we formulate conceptually novel social neuroscience paradigm (OSIMAS), which envisages social systems emerging from the coherent neurodynamical processes taking place in the individual mind-fields. In this way, societies are understood as global processes emerging from the superposition of the conscious and subconscious mind-fields of individual members of society. For the experimental validation of the biologically inspired OSIMAS paradigm, we have designed a framework of EEG-based experiments. Initial baseline individual tests of spectral cross-correlations of EEG-recorded brainwave patterns for some mental states have been provided in this paper. Preliminary experimental results do not refute the main OSIMAS postulates. This paper also provides some insights for the construction of OSIMAS-based simulation models.

  16. Synthetic Nanoelectronic Probes for Biological Cells and Tissue

    PubMed Central

    2013-01-01

    Research at the interface between nanoscience and biology has the potential to produce breakthroughs in fundamental science and lead to revolutionary technologies. In this review, we focus on nanoelectronic/biological interfaces. First, we discuss nanoscale field effect transistors (nanoFETs) as probes to study cellular systems, including the realization of nanoFET comparable in size to biological nanostructures involved in communication using synthesized nanowires. Second, we overview current progress in multiplexed extracellular sensing using planar nanoFET arrays. Third, we describe the design and implementation of three distinct nanoFETs used to realize the first intracellular electrical recording from single cells. Fourth, we present recent progress in merging electronic and biological systems at the 3D tissue level by using macroporous nanoelectronic scaffolds. Finally, we discuss future development in this research area, the unique challenges and opportunities, and the tremendous impact these nanoFET based technologies might have in advancing biology and medical sciences. PMID:23451719

  17. The evolution of "Life": A Metadarwinian integrative approach.

    PubMed

    De Loof, Arnold

    2017-01-01

    It is undeniably very logical to first formulate an unambiguous definition of "Life" before engaging in defining the parameters instrumental to Life's evolution. Because nearly everybody assumes, erroneously in my opinion, that catching Life's essence in a single sentence is impossible, this way of thinking remained largely unexplored in evolutionary theory. Upon analyzing what exactly happens at the transition from "still alive" to "just dead," the following definition emerged. What we call "Life" (L) is an activity . It is nothing other than the total sum (∑) of all communication acts (C) executed, at moment t, by entities organized as sender-receiver compartments: L = ∑C Such "living" entities are self-electrifying and talking ( = communicating) aggregates of fossil stardust operating in an environment heavily polluted by toxic calcium. Communication is a multifaceted, complex process that is seldom well explained in introductory textbooks of biology. Communication is instrumental to adaptation because, at the cellular level, any act of communication is in fact a problem-solving act. It can be logically deduced that not Natural Selection itself but communication/problem-solving activity preceding selection is the universal driving force of evolution. This is against what textbooks usually claim, although doubt on the status of Natural Selection as driving force has been around for long. Finally, adopting the sender-receiver with its 2 memory systems (genetic and cognitive, both with their own rules) and 2 types of progeny ("physical children" and "pupils") as the universal unit of architecture and function of all living entities, also enables the seamless integration of cultural and organic evolution, another long-standing tough problem in evolutionary theory. Paraphrasing Theodosius Dobzhansky, the very essence of biology is: "Nothing in biology and evolutionary theory makes sense except in the light of the ability of living matter to communicate, and by doing so, to solve problems."

  18. The evolution of “Life”: A Metadarwinian integrative approach

    PubMed Central

    De Loof, Arnold

    2017-01-01

    ABSTRACT It is undeniably very logical to first formulate an unambiguous definition of “Life” before engaging in defining the parameters instrumental to Life's evolution. Because nearly everybody assumes, erroneously in my opinion, that catching Life's essence in a single sentence is impossible, this way of thinking remained largely unexplored in evolutionary theory. Upon analyzing what exactly happens at the transition from “still alive” to “just dead,” the following definition emerged. What we call “Life” (L) is an activity. It is nothing other than the total sum (∑) of all communication acts (C) executed, at moment t, by entities organized as sender-receiver compartments: L = ∑C Such “living” entities are self-electrifying and talking ( = communicating) aggregates of fossil stardust operating in an environment heavily polluted by toxic calcium. Communication is a multifaceted, complex process that is seldom well explained in introductory textbooks of biology. Communication is instrumental to adaptation because, at the cellular level, any act of communication is in fact a problem-solving act. It can be logically deduced that not Natural Selection itself but communication/problem-solving activity preceding selection is the universal driving force of evolution. This is against what textbooks usually claim, although doubt on the status of Natural Selection as driving force has been around for long. Finally, adopting the sender-receiver with its 2 memory systems (genetic and cognitive, both with their own rules) and 2 types of progeny (”physical children” and “pupils”) as the universal unit of architecture and function of all living entities, also enables the seamless integration of cultural and organic evolution, another long-standing tough problem in evolutionary theory. Paraphrasing Theodosius Dobzhansky, the very essence of biology is: “Nothing in biology and evolutionary theory makes sense except in the light of the ability of living matter to communicate, and by doing so, to solve problems.” PMID:28702123

  19. Wearable Smart System for Visually Impaired People

    PubMed Central

    2018-01-01

    In this paper, we present a wearable smart system to help visually impaired persons (VIPs) walk by themselves through the streets, navigate in public places, and seek assistance. The main components of the system are a microcontroller board, various sensors, cellular communication and GPS modules, and a solar panel. The system employs a set of sensors to track the path and alert the user of obstacles in front of them. The user is alerted by a sound emitted through a buzzer and by vibrations on the wrist, which is helpful when the user has hearing loss or is in a noisy environment. In addition, the system alerts people in the surroundings when the user stumbles over or requires assistance, and the alert, along with the system location, is sent as a phone message to registered mobile phones of family members and caregivers. In addition, the registered phones can be used to retrieve the system location whenever required and activate real-time tracking of the VIP. We tested the system prototype and verified its functionality and effectiveness. The proposed system has more features than other similar systems. We expect it to be a useful tool to improve the quality of life of VIPs. PMID:29533970

  20. Wearable Smart System for Visually Impaired People.

    PubMed

    Ramadhan, Ali Jasim

    2018-03-13

    In this paper, we present a wearable smart system to help visually impaired persons (VIPs) walk by themselves through the streets, navigate in public places, and seek assistance. The main components of the system are a microcontroller board, various sensors, cellular communication and GPS modules, and a solar panel. The system employs a set of sensors to track the path and alert the user of obstacles in front of them. The user is alerted by a sound emitted through a buzzer and by vibrations on the wrist, which is helpful when the user has hearing loss or is in a noisy environment. In addition, the system alerts people in the surroundings when the user stumbles over or requires assistance, and the alert, along with the system location, is sent as a phone message to registered mobile phones of family members and caregivers. In addition, the registered phones can be used to retrieve the system location whenever required and activate real-time tracking of the VIP. We tested the system prototype and verified its functionality and effectiveness. The proposed system has more features than other similar systems. We expect it to be a useful tool to improve the quality of life of VIPs.

Top