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Sample records for single-thread tie channels

  1. Formation and maintenance of single-thread tie channels entering floodplain lakes: Observations from three diverse river systems

    Science.gov (United States)

    Rowland, J. C.; Dietrich, W. E.; Day, G.; Parker, G.

    2009-06-01

    Tie channels connect rivers to floodplain lakes on many lowland rivers and thereby play a central role in floodplain sedimentology and ecology; yet they are generally unrecognized and little studied. Here we report the results of field studies focused on tie channel origin and morphodynamics in the following three contrasting systems: the Middle Fly River (Papua New Guinea), the Lower Mississippi River, and Birch Creek in Alaska. Across these river systems, tie channels vary by an order of magnitude in size but exhibit the same characteristic morphology and appear to develop and evolve by a similar set of processes. In all three systems, the channels are characterized by a narrow, leveed, single-thread morphology with maximum width approximately one tenth the width of the mainstem river. The channels typically have a V-shaped cross section, unlike most fluvial channels. These channels develop as lakes become isolated from the river by sedimentation. Narrowing of the connection between river and lake causes a sediment-laden jet to develop. Levees develop along the margins of the jet leading to channel emergence and eventual levee aggradation to the height of the mainstem levees. Bidirectional flow in these channels is common. Outflows from the lake scour sediment and prevent channel blockage. We propose that channel geometry and size are then controlled by a dynamic balance between channel narrowing by suspended sediment deposition and incision and widening by mass failure of banks during outflows. Tie channels are laterally stable and may convey flow for hundreds to a few thousand of years.

  2. The formation and maintenance of single-thread tie channels entering floodplain lakes: observations from three diverse river systems

    Energy Technology Data Exchange (ETDEWEB)

    Rowland, Joel C [Los Alamos National Laboratory; Dietrich, William E [UC BERKELEY; Day, Geoff [NEWCREST MINING; Parker, Gary [UNIV OF ILLINOIS

    2009-01-01

    Tie channels connect rivers to floodplain lakes on many lowland rivers and thereby play a central role in floodplain sedimentology and ecology, yet they are generally unrecognized and little studied. here we report the results of field studies focused on tie channel origin and morphodynamics in three contrasting systems: the Middle Fly River, Papua New Guinea, the Lower Mississippi River, and Birch Creek in Alaska. Across these river systems, tie channels vary by an order of magnitude in size but exhibit the same characteristic morphology and appear to develop and evolve by a similar set of processes. In all three systems, the channels are characterized by a narrow, leveed single-thread morphology with maximum width approximately one tenth the width of the mainstem river. The channels typically have a V shaped cross-section, unlike most fluvial channels. These channels develop as lakes become isolated from the river by sedimentation. Narrowing of the connection between river and lake causes a sediment-laden jet to develop. Levees develop along the margins of the jet leading to channel emergence and eventual levee aggradation to the height of the mainstem levees. Bi-directional flow in these channels is common. Outflows from the lake scour sediment and prevent channel blockage. We propose that channel geometry and size are then controlled by a dynamic balance between channel narrowing by suspended sediment deposition and incision and widening by mass failure of banks during outflows. Tie channels are laterally stable and may convey flow for hundreds to a few thousand of years.

  3. Understanding Single-Thread Meandering Rivers with High Sinuosity on Mars through Chemical Precipitation Experiments

    Science.gov (United States)

    Lim, Y.; Kim, W.

    2015-12-01

    Meandering rivers are extremely ubiquitous on Earth, yet it is only recently that single-thread experimental channels with low sinuosity have been created. In these recent experiments, as well as in natural rivers, vegetation plays a crucial role in maintaining a meandering pattern by adding cohesion to the bank and inhibiting erosion. The ancient, highly sinuous channels found on Mars are enigmatic because presumably vegetation did not exist on ancient Mars. Under the hypothesis that Martian meandering rivers formed by chemical precipitation on levees and flood plain deposits, we conducted carbonate flume experiments to investigate the formation and evolution of a single-thread meander pattern without vegetation. The flow recirculating in the flume is designed to accelerate chemical reactions - dissolution of limestone using CO2 gas to produce artificial spring water and precipitation of carbonates to increase cohesion- with precise control of water discharge, sediment discharge, and temperature. Preliminary experiments successfully created a single-thread meandering pattern through chemical processes. Carbonate deposits focused along the channel sides improved the bank stability and made them resistant to erosion, which led to a stream confined in a narrow path. The experimental channels showed lateral migration of the bend through cut bank and point bar deposits; intermittent floods created overbank flow and encouraged cut bank erosion, which enhanced lateral migration of the channel, while increase in sediment supply improved lateral point bar deposition, which balanced erosion and deposition rates. This mechanism may be applied to terrestrial single-thread and/or meandering rivers with little to no vegetation or before its introduction to Earth and also provide the link between meandering river records on Mars to changes in Martian surface conditions.

  4. Circuitous to single thread: post-dam geomorphic transformation of the Colorado River in its delta

    Science.gov (United States)

    Mueller, E. R.; Schmidt, J. C.

    2017-12-01

    The Colorado River in its delta has transformed from a maze of secondary and distributary channels to an intermittent or ephemeral stream largely disconnected from formerly active channels and floodplains. Periodic post-dam floods have demonstrated that channel migration and shifting during floods increased the extent and diversity of riparian vegetation, and suggested that restoration of fluvial processes that promote re-activation of these former channels may enhance ecosystem rehabilitation. But restoration efforts in the delta are complicated by the fact that the Colorado River has the largest reservoir size in relation to its mean annual flow of any large river in North America and most of its sediment supply is completely blocked in upstream reservoirs. As a result, small controlled floods intended to inundate formerly active channels and rejuvenate riparian vegetation must consider the new relationship between stream flow and the delta's transformed geomorphology. Post-dam channel change has been dominated by the abandonment of secondary and distributary channels, with 3 to 4 meters of bed incision in the upstream part of the delta that diminishes downstream. Initial bed incision of 2 to 3 meters occurred rapidly following completion of Hoover Dam in 1936, before further upstream water development reduced delta flows to near zero by the mid-1960s. The largest post-dam floods occurred in the 1980s, which resulted in 10s to 100s of meters of lateral migration, channel switching, and the reactivation of secondary channels and floodplains rarely inundated since dam completion. Smaller flow pulses in the 1990s and 2000s further incised the thalweg to its minimum elevation, resulting in a narrow single-thread channel inset within the multi-channel surface active during the 1980s. In 2014, an experimental pulse flow was released to the river channel with a peak discharge approximately 5% of the typical pre-dam flood peak. Topographic change was confined to the main

  5. The Missing Link: the Role of Floodplain Tie Channels in Connecting Off River Water Bodies to Lowland Rivers

    Science.gov (United States)

    Rowland, J. C.; Dietrich, W. E.; Day, G.

    2005-05-01

    Along lowland river systems across the globe the exchange of water, sediment, carbon, nutrients and biota between main stem rivers and off-river water bodies (ORWB) is facilitated by the presence of stable secondary channels referred to here as tie channels. Sixty five percent of the ORWB along the middle Fly River in Papua New Guinea connect to the river through such channels. A similar percentage of the 37 ORWB located between Baton Rouge and Memphis on the lower Mississippi River at one time were linked to the river by tie or batture (as they are locally known) channels. Levee construction and other alterations aimed at flood control or navigation on the Mississippi have left only a handful of lakes connected to the river, of these, most are heavily altered by dredging or other modifications. Tie channels were also once common along major tributaries to the Mississippi, such as the Red River. In the much less disturbed Alaskan environment, tie channels are still common, especially along Birch Creek and the Koyukuk and Black rivers. Our studies on the Mississippi River, in Alaska and in Papua New Guinea indicate that tie channels possess a common channel form that is stable and self-maintaining for hundreds to possibly a thousand years. Tie channels exhibit narrow width to depth ratios (~ 5.5) and consistently scale in cross-sectional dimensions to the size of the lake into which they flow. Variations in river and lake stage drive flow bi-directionally through tie channels. A local high or sill in the bed of tie channels controls the degree and duration of connection between the river and ORWB, with many lakes becoming isolated during periods of low stage. The life-span of a tie channel depends on the rate of sediment loading to the ORWB. Our research indicates that this rate directly corresponds to the sediment loading in the main stem river. Along the Fly River, for example, a 5 to 7 fold increase in the river sediment load has resulted increases of 6 to 17

  6. The Role of Conjoining (Tie) Channels in Lowland Floodplain Development and Lake Infilling

    Science.gov (United States)

    Rowland, J. C.; Dietrich, W. E.; Day, G.; Lepper, K.; Wilson, C. J.

    2003-12-01

    In simple models of lowland river systems, water and sediment enter the main stem via tributary and secondary channels and are only redistributed to the floodplain during overbank and crevasse splay events. Along numerous river systems across the globe, however, water and sediment are regularly exchanged between the river and off river water bodies via stable, narrow channels. These channels, known as tie channels on the Fly River in Papua New Guinea and batture channels along the lower Mississippi, are largely overlooked but important components of floodplain sediment dispersal where they exist. These channels become pathways of sediment dispersal to the floodplain system when elevated river stages force sediment-laden flows into the off-river water bodies. On the Fly River, it is estimated that about 50% of the sediment delivery to the floodplain is via these channels, and along low gradient tributary channels during flood driven flow reversals. During low flow, tie channels serve to drain the floodplain. With the outgoing flows, large amounts sediment can be carried and lost to the floodplain; floodplain lakes progressively infill with sediment as the mouth of these channels steadily prograde lakeward. These lake deposits not only become significant stratigraphic components of floodplains (traditionally referred to as clay plugs), but are important local sinks recording hundreds to thousands of years of river history. As with all sinks, the proper interpretation of these stratigraphic records requires understanding the processes by which sediment is delivered to the sink and how these processes alter the paleohydraulic and climatic signals of interest. We have conducted field investigations of conjoining channels in Papua New Guinea (the Fly and Strickland Rivers), Louisiana (Raccourci Old River ~ 65 km upriver of Baton Rouge) and Alaska (Birch Creek). These field investigations include extensive surveys of both cross and along channel morphological trends

  7. Single-Thread-Based Wearable and Highly Stretchable Triboelectric Nanogenerators and Their Applications in Cloth-Based Self-Powered Human-Interactive and Biomedical Sensing

    KAUST Repository

    Lai, Ying-Chih

    2016-11-03

    The development of wearable and large-area fabric energy harvester and sensor has received great attention due to their promising applications in next-generation autonomous and wearable healthcare technologies. Here, a new type of “single” thread-based triboelectric nanogenerator (TENG) and its uses in elastically textile-based energy harvesting and sensing have been demonstrated. The energy-harvesting thread composed by one silicone-rubber-coated stainless-steel thread can extract energy during contact with skin. With sewing the energy-harvesting thread into a serpentine shape on an elastic textile, a highly stretchable and scalable TENG textile is realized to scavenge various kinds of human-motion energy. The collected energy is capable to sustainably power a commercial smart watch. Moreover, the simplified single triboelectric thread can be applied in a wide range of thread-based self-powered and active sensing uses, including gesture sensing, human-interactive interfaces, and human physiological signal monitoring. After integration with microcontrollers, more complicated systems, such as wireless wearable keyboards and smart beds, are demonstrated. These results show that the newly designed single-thread-based TENG, with the advantage of interactive, responsive, sewable, and conformal features, can meet application needs of a vast variety of fields, ranging from wearable and stretchable energy harvesters to smart cloth-based articles.

  8. Single-Thread-Based Wearable and Highly Stretchable Triboelectric Nanogenerators and Their Applications in Cloth-Based Self-Powered Human-Interactive and Biomedical Sensing

    KAUST Repository

    Lai, Ying-Chih; Deng, Jianan; Zhang, Steven L.; Niu, Simiao; Guo, Hengyu; Wang, Zhong Lin

    2016-01-01

    The development of wearable and large-area fabric energy harvester and sensor has received great attention due to their promising applications in next-generation autonomous and wearable healthcare technologies. Here, a new type of “single” thread-based triboelectric nanogenerator (TENG) and its uses in elastically textile-based energy harvesting and sensing have been demonstrated. The energy-harvesting thread composed by one silicone-rubber-coated stainless-steel thread can extract energy during contact with skin. With sewing the energy-harvesting thread into a serpentine shape on an elastic textile, a highly stretchable and scalable TENG textile is realized to scavenge various kinds of human-motion energy. The collected energy is capable to sustainably power a commercial smart watch. Moreover, the simplified single triboelectric thread can be applied in a wide range of thread-based self-powered and active sensing uses, including gesture sensing, human-interactive interfaces, and human physiological signal monitoring. After integration with microcontrollers, more complicated systems, such as wireless wearable keyboards and smart beds, are demonstrated. These results show that the newly designed single-thread-based TENG, with the advantage of interactive, responsive, sewable, and conformal features, can meet application needs of a vast variety of fields, ranging from wearable and stretchable energy harvesters to smart cloth-based articles.

  9. Pseudo 2-transistor active pixel sensor using an n-well/gate-tied p-channel metal oxide semiconductor field eeffect transistor-type photodetector with built-in transfer gate

    Science.gov (United States)

    Seo, Sang-Ho; Seo, Min-Woong; Kong, Jae-Sung; Shin, Jang-Kyoo; Choi, Pyung

    2008-11-01

    In this paper, a pseudo 2-transistor active pixel sensor (APS) has been designed and fabricated by using an n-well/gate-tied p-channel metal oxide semiconductor field effect transistor (PMOSFET)-type photodetector with built-in transfer gate. The proposed sensor has been fabricated using a 0.35 μm 2-poly 4-metal standard complementary metal oxide semiconductor (CMOS) logic process. The pseudo 2-transistor APS consists of two NMOSFETs and one photodetector which can amplify the generated photocurrent. The area of the pseudo 2-transistor APS is 7.1 × 6.2 μm2. The sensitivity of the proposed pixel is 49 lux/(V·s). By using this pixel, a smaller pixel area and a higher level of sensitivity can be realized when compared with a conventional 3-transistor APS which uses a pn junction photodiode.

  10. Comparison of in-vivo failure of single-thread and dual-thread temporary anchorage devices over 18 months: A split-mouth randomized controlled trial.

    Science.gov (United States)

    Durrani, Owais Khalid; Shaheed, Sohrab; Khan, Arsalan; Bashir, Ulfat

    2017-10-01

    The purpose of this study was to compare the in-vivo failure rates of single-thread and dual-thread temporary anchorage device (TAD) designs over 18 months. Thirty patients with skeletal Class II Division 1 malocclusion requiring anchorage from TADs for retraction of maxillary incisors into the extracted premolar space were recruited in this parallel group, split-mouth, randomized controlled trial. A block randomization sequence was generated with Random Allocation Software (version 2.0; Isfahan, Iran) with the allocations concealed in sequentially numbered, opaque, sealed envelopes. A total of 60 TADs (diameter, 2 mm; length, 10 mm) were placed in the maxillary arches of these patients with random allocation of the 2 types to the left and the right sides in a 1:1 ratio. All TADs were placed between the roots of the second premolar and the first molar and were immediately loaded. Patients were followed for a minimum of 12 months and a maximum of 18 months for the failure of the TADs. Data were analyzed blindly on an intention-to-treat basis. Four TADs (13.3%) failed in the single-thread group, and 6 TADs (20%) failed in the dual-thread group. The McNemar test showed an insignificant difference (P = 0.72) between the 2 groups. An odds ratio of 1.6 (95% confidence interval, 0.39-6.97) showed no significant associations among the variables. Most TADs failed in the first month after insertion (50%). The failure rate of dual-thread TADs compared with single-thread TADs is statistically insignificant when placed in the maxilla for retraction of the anterior segment. Registration: The trial was not registered before commencement. The protocol was not published before the trial. Copyright © 2016 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

  11. Network ties and survival

    DEFF Research Database (Denmark)

    Acheampong, George; Narteh, Bedman; Rand, John

    2017-01-01

    Poultry farming has been touted as one of the major ways by which poverty can be reduced in low-income economies like Ghana. Yet, anecdotally there is a high failure rate among these poultry farms. This current study seeks to understand the relationship between network ties and survival chances...... of small commercial poultry farms (SCPFs). We utilize data from a 2-year network survey of SCPFs in rural Ghana. The survival of these poultry farms are modelled using a lagged probit model of farms that persisted from 2014 into 2015. We find that network ties are important to the survival chances...... but this probability reduces as the number of industry ties increases but moderation with dynamic capability of the firm reverses this trend. Our findings show that not all network ties aid survival and therefore small commercial poultry farmers need to be circumspect in the network ties they cultivate and develop....

  12. Commercial lumber, round timbers, and ties

    Science.gov (United States)

    David E. Kretschmann

    2010-01-01

    When sawn, a log yields round timber, ties, or lumber of varying quality. This chapter presents a general discussion of grading, standards, and specifications for these commercial products. In a broad sense, commercial lumber is any lumber that is bought or sold in the normal channels of commerce. Commercial lumber may be found in a variety of forms, species, and types...

  13. More ties than we thought

    Directory of Open Access Journals (Sweden)

    Dan Hirsch

    2015-05-01

    Full Text Available We extend the existing enumeration of neck tie-knots to include tie-knots with a textured front, tied with the narrow end of a tie. These tie-knots have gained popularity in recent years, based on reconstructions of a costume detail from The Matrix Reloaded, and are explicitly ruled out in the enumeration by Fink & Mao (2000. We show that the relaxed tie-knot description language that comprehensively describes these extended tie-knot classes is context free. It has a regular sub-language that covers all the knots that originally inspired the work. From the full language, we enumerate 266,682 distinct tie-knots that seem tie-able with a normal neck-tie. Out of these 266,682, we also enumerate 24,882 tie-knots that belong to the regular sub-language.

  14. Channel follower leakage restrictor

    International Nuclear Information System (INIS)

    Williamson, H.E.; Smith, B.A.

    1977-01-01

    An improved means is provided to control coolant leakage between the flow channel and the lower tie plate of a nuclear fuel assembly. The means includes an opening in the lower tie plate and a movable element adjacent thereto. The coolant pressure within the tie plate biases the movable means toward the inner surface of the surrounding flow channel to compensate for any movement of the flow channel away from the lower tie plate to thereby control the leakage of coolant flow from the fuel assemblies to the spaces among the fuel assemblies of the core. 9 figures

  15. Relevant ties matter

    DEFF Research Database (Denmark)

    Larsen, Christian Albrekt; Pedersen, Jacob; Mouw, Ted

    What is the effect of social networks on labor market outcomes? The tradition following Grannovetter claims that social ties have a positive effect on wages, job prestige and job satisfaction. Although a number of studies have found positive correlations between friendship characteristics and lab...

  16. All tied up: Tied staying and tied migration within the United States, 1997 to 2007

    Directory of Open Access Journals (Sweden)

    Thomas J. Cooke

    2013-10-01

    Full Text Available Background: The family migration literature presumes that women are cast into the role of the tied migrant. However, clearly identifying tied migrants is a difficult empirical task since it requires the identification of a counterfactual: Who moved but did not want to? Objective: This research develops a unique methodology to directly identify both tied migrants and tied stayers in order to investigate their frequency and determinants. Methods: Using data from the 1997 through 2009 U.S. Panel Study of Income Dynamics (PSID, propensity score matching is used to match married individuals with comparable single individuals to create counterfactual migration behaviors: who moved but would not have moved had they been single (tied migrants and who did not move but would have moved had they been single (tied stayers. Results: Tied migration is relatively rare and not limited just to women: rates of tied migration are similar for men and women. However, tied staying is both more common than tied migration and equally experienced by men and women. Consistent with the body of empirical evidence, an analysis of the determinants of tied migration and tied staying demonstrates that family migration decisions are imbued with gender. Conclusions: Additional research is warranted to validate the unique methodology developed in this paper and to confirm its results. One line of future research should be to examine the effects of tied staying, along with tied migration, on well-being, union stability, employment, and earnings.

  17. New Tech, New Ties:

    DEFF Research Database (Denmark)

    Ling, Richard

    regardless of where they are. But when we are engaged in these intimate conversations with absent friends, what happens to our relationship with the people who are actually in the same room with us? In New Tech, New Ties, Rich Ling examines how the mobile telephone affects both kinds of interactions......The message of this book is simple: the mobile phone strengthens social bonds among family and friends. With a traditional land-line telephone, we place calls to a location and ask hopefully if someone is "there"; with a mobile phone, we have instant and perpetual access to friends and family......—those mediated by mobile communication and those that are face to face. Ling finds that through the use of various social rituals the mobile telephone strengthens social ties within the circle of friends and family—sometimes at the expense of interaction with those who are physically present—and creates what he...

  18. The Tie retraction syndrome.

    Science.gov (United States)

    Geerling, Gerd; Neppert, Birte; Hemmant, Bridget

    2012-12-01

    Tissue retraction is implicated in the pathogenesis of various ophthalmic disorders. Here we describe the clinical characteristics, epidemiology and pathophysiology of a form of retraction syndrome which - to the best of our knowledge - has not been reported in the ophthalmic literature so far. We have termed this condition - consisting of a slowly progressive pseudovertical shortening of tie length due to a horizontal extension of girth length - the "Tie retraction syndrome" (TRS). Other pathognomonic features include an increased tie tip to belt buckle distance and a prolapse of the subumbilical fat pad (SUFP). The syndrome has a clear male to female preponderance and shows an increasing incidence with age and income before tax. Based on a newly proposed grading scheme we discuss and illustrate the diagnosis as well as the medical and surgical management options of this abundant, but often undiagnosed condition. The authors have no explanation for the apparent lack of awareness for this widely preponderant syndrome and its severe cosmetically disfiguring potential. We thus would like to invite all fellow colleagues with expertise in the field to comment or present their views.

  19. Family ties and residential locations

    NARCIS (Netherlands)

    Mulder, C.H.; Cooke, T.J.

    2009-01-01

    In this paper, and in the Special Issue it introduces, the focus is on the role of family ties in residential location choice and, conversely, the role of residential locations in maintaining family ties. Not only do events in the nuclear family trigger residential relocations, but nearby family

  20. Why do leaf-tying caterpillars abandon their leaf ties?

    Directory of Open Access Journals (Sweden)

    Michelle Sliwinski

    2013-09-01

    Full Text Available Leaf-tying caterpillars act as ecosystem engineers by building shelters between overlapping leaves, which are inhabited by other arthropods. Leaf-tiers have been observed to leave their ties and create new shelters (and thus additional microhabitats, but the ecological factors affecting shelter fidelity are poorly known. For this study, we explored the effects of resource limitation and occupant density on shelter fidelity and assessed the consequences of shelter abandonment. We first quantified the area of leaf material required for a caterpillar to fully develop for two of the most common leaf-tiers that feed on white oak, Quercus alba. On average, Psilocorsis spp. caterpillars consumed 21.65 ± 0.67 cm2 leaf material to complete development. We also measured the area of natural leaf ties found in a Maryland forest, to determine the distribution of resources available to caterpillars in situ. Of 158 natural leaf ties examined, 47% were too small to sustain an average Psilocorsis spp. caterpillar for the entirety of its development. We also manipulated caterpillar densities within experimental ties on potted trees to determine the effects of cohabitants on the likelihood of a caterpillar to leave its tie. We placed 1, 2, or 4 caterpillars in ties of a standard size and monitored the caterpillars twice daily to track their movement. In ties with more than one occupant, caterpillars showed a significantly greater propensity to leave their tie, and left sooner and at a faster rate than those in ties as single occupants. To understand the consequences of leaf tie abandonment, we observed caterpillars searching a tree for a site to build a shelter in the field. This is a risky behavior, as 17% of the caterpillars observed died while searching for a shelter site. Caterpillars that successfully built a shelter traveled 110 ± 20 cm and took 28 ± 7 min to find a suitable site to build a shelter. In conclusion, leaf-tying caterpillars must frequently

  1. Tie Content in Professional Networks

    DEFF Research Database (Denmark)

    Zarzecka, Olga

    in resource exchanges and the effect of these differences on the number of, and extent to which, resources are provided by a network tie. Chapter 3 explores how firm underperfomance and social identity with corporate elite alter types of resources a network tie provides. Chapter 4 focuses on a tie’s internal......Professional networks of senior managers have indisputable value for them as well as for their organizations. In recent years, much attention has been given to the structure of these networks as it reflects senior managers’ opportunity to access valuable resources. Surprisingly, the actual...... resources that senior managers acquire through their network ties, i.e. the tie content, remain heavily understudied. Hence, the purpose of this dissertation is to answer the following question: What resources flow through informal ties in senior managers’ professional networks, and why? The first chapter...

  2. 23 CFR 635.111 - Tied bids.

    Science.gov (United States)

    2010-04-01

    ... MAINTENANCE Contract Procedures § 635.111 Tied bids. (a) The STD may tie or permit the tying of Federal-aid...-financed highway projects may be combined in one contract if the conditions of the projects are so similar...

  3. Instability of ties in compression

    DEFF Research Database (Denmark)

    Buch-Hansen, Thomas Cornelius

    2013-01-01

    Masonry cavity walls are loaded by wind pressure and vertical load from upper floors. These loads results in bending moments and compression forces in the ties connecting the outer and the inner wall in a cavity wall. Large cavity walls are furthermore loaded by differential movements from...... the temperature gradient between the outer and the inner wall, which results in critical increase of the bending moments in the ties. Since the ties are loaded by combined compression and moment forces, the loadbearing capacity is derived from instability equilibrium equations. Most of them are iterative, since...... exact instability solutions are complex to derive, not to mention the extra complexity introducing dimensional instability from the temperature gradients. Using an inverse variable substitution and comparing an exact theory with an analytical instability solution a method to design tie...

  4. Senior Managers’ Network Tie Use

    DEFF Research Database (Denmark)

    Zarzecka, Olga; Villeseche, Florence

    While the importance or even necessity to build and maintain resourceful social networks appears as a forthright fact, there is still a lack of certainty as to who benefits from the resources that can be accessed through senior managers’ networks, and under what conditions. In this paper, we...... contribute to answering this puzzle with a sample constituted of senior managers from Denmark and their network ties, and investigate both economic and sociological conditions of senior managers’ tie use. Our results show that the greater the distance between aspiration level and actual firm performance......, the more likely it is that senior managers will use their network ties to access resources that benefit chiefly the individual rather than the organization. In addition, we demonstrate that this rapport is moderated by senior managers’ social identity as a member of the corporate elite, so that a strong...

  5. Analysis of ILRS Site Ties

    Science.gov (United States)

    Husson, V. S.; Long, J. L.; Pearlman, M.

    2001-12-01

    By the end of 2000, 94% of ILRS stations had completed station and site information forms (i.e. site logs). These forms contain six types of information. These six categories include site identifiers, contact information, approximate coordinates, system configuration history, system ranging capabilities, and local survey ties. The ILRS Central Bureau, in conjunction with the ILRS Networks and Engineering Working Group, has developed procedures to quality control site log contents. Part of this verification entails data integrity checks of local site ties and is the primary focus of this paper. Local survey ties are critical to the combination of space geodetic network coordinate solutions (i.e. GPS, SLR, VLBI, DORIS) of the International Terrestrial Reference Frame (ITRF). Approximately 90% of active SLR sites are collocated with at least one other space geodetic technique. The process used to verify these SLR ties, at collocated sites, is identical to the approach used in ITRF2000. Local vectors (X, Y, Z) from each ILRS site log are differenced from its corresponding ITRF2000 position vectors (i.e. no transformations). These X, Y, and Z deltas are converted into North, East, and Up. Any deltas, in any component, larger than 5 millimeter is flagged for investigation. In the absence of ITRF2000 SLR positions, CSR positions were used. To further enhance this comparison and to fill gaps in information, local ties contained in site logs from the other space geodetic services (i.e. IGS, IVS, IDS) were used in addition to ITRF2000 ties. Case studies of two collocated sites (McDonald/Ft. Davis and Hartebeeshtoek) will be explored in-depth. Recommendations on how local site surveys should be conducted and how this information should be managed will also be presented.

  6. The Strength of Direct Ties

    DEFF Research Database (Denmark)

    Claussen, Jörg; Falck, Oliver; Grosjean, Thorsten

    2012-01-01

    We analyze the economic effects of a developer's connectedness in the electronic game industry. Knowledge spillovers between developers are likely to be of special relevance in this knowledge-intensive and regionally concentrated industry. We calculate social network measures for a developer......'s connectedness to other developers at multiple points in time. In a regression in which we exploit within-career variation in social network measures, we find that the number of direct ties a developer has to other developers has a strong effect on both a game's revenues and critics' scores. The quality...... of indirect ties makes no additional contribution to the game's success....

  7. Do recruitment ties affect wages?

    DEFF Research Database (Denmark)

    Larsen, Anna Folke; Rand, John; Torm, Nina Elisabeth

    This paper examines the extent to which recruitment ties affect individual wage outcomes in small and medium scale manufacturing firms. Based on a unique matched employer-employee dataset from Vietnam we find that there is a significant positive wage premium associated with obtaining a job through...... an informal contact, when controlling for standard determinants of wage compensation. Moreover, we show that the mechanism through which informal contacts affect wages depends on the type of recruitment tie used. The findings are robust across location, firm size categories and different worker types....

  8. Family Ties and Civic Virtues

    DEFF Research Database (Denmark)

    Ljunge, Jan Martin

    I establish a positive relationship between family ties and civic virtues, as captured by disapproval of tax and benefit cheating, corruption, and a range of other dimensions of exploiting others for personal gain. I find that family ties are a complement to social capital, using within country...... evidence from 83 nations and data on second generation immigrants in 29 countries with ancestry in 85 nations. Strong families cultivate universalist values and produce more civic and altruistic individuals. The results provide a constructive role for families in promoting family values that support...

  9. PWR integral tie plate and locking mechanism

    International Nuclear Information System (INIS)

    Flora, B.S.; Osborne, J.L.

    1980-01-01

    A locking mechanism for securing an upper tie plate to the tie rods of a nuclear fuel bundle is described. The mechanism includes an upper tie plate assembly and locking sleeves fixed to the ends of the tie rods. The tie plate is part of the upper tie plate assembly and is secured to the fuel bundle by securing the entire upper tie plate assembly to the locking sleeves fixed to the tie rods. The assembly includes, in addition to the tie plate, locking nuts for engaging the locking sleeves, retaining sleeves to operably connect the locking nuts to the assembly, a spring biased reaction plate to restrain the locking nuts in the locked position and a means to facilitate the removal of the entire assembly as a unit from the fuel bundle

  10. Channel Responses and Hydromodification in Southern California

    Science.gov (United States)

    Hawley, R. J.; Dust, D. W.; Bledsoe, B. P.

    2007-12-01

    Hydromodification (changes in watershed hydrologic characteristics, and the resulting hydraulics and channel forms due to urbanization) is ubiquitous in Southern California. In this region, the effects of hydromodification are driven and compounded by the arid/semiarid climate, high relief, erodible soils, high urbanization rates, and relatively low frequency of retention/detention. We conducted a preliminary survey of over 50 stream reaches along a gradient from least disturbed to fully urbanized. All stages of the Channel Evolution Model (CEM) of Schumm et al. (1984) were observed, from stable to degrading, widening, aggrading, and quasi-equilibrium channels. Several sites have CEM stages II through V in close proximity due to headcutting, hardpoints, and infrastructure. We also observed channels in undeveloped watersheds impacted by downstream urbanization via headcutting. A range of intervention measures was observed, with the frequent evolutionary endpoint as a concrete engineered flood control channel. We also observed multiple channel evolution sequences that deviate from the CEM for single-thread, incising channels. An alternative channel response, particularly on smaller urbanized streams is a stabilized, vegetation encroached low-flow channel with regular baseflow supplied by residential irrigation runoff. The limited cases of unimpacted streams that remain tend to be high gradient, high energy systems that are naturally proximate to the transition between braided and meandering form for a given sediment size.

  11. Peru turnaround tied to privatization

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    Petroleos del Peru predicts a 10% increase in Peru's oil production this year and a further increase in 1994. Petroperu also forecasts a sharp increase in drilling in Peru this year. After several years of declining oil production, a gradual turnaround in the cash strapped country's petroleum industry is largely tied to its progress in privatization. The government last year began a campaign to privatize all state owned companies by the end of July 1995. The paper discusses forecasts by Petroperu; the contract of Occidental del Amazonas Inc.; the Petromar privatization; Great Western's contract; development of the Aguaytia gas field; and refinery contracts

  12. Social Ties for Labor Market Access

    DEFF Research Database (Denmark)

    Dorner, Matthias; Harhoff, Dietmar; Hinz, Tina

    such ties. However, mobility decisions made by inventors with outstanding patenting track records (star inventors) were not impacted by social ties. We conclude that social ties support labor market access for migrant inventors and determine regional choices while dependence on these ties is substantially......We study the impact of social ties on the migration of inventors from East to West Germany, using the fall of the Iron Curtain and German reunification as a natural experiment. We identify East German inventors via their patenting track records prior to 1990 and their social security records...... in the German labor market after reunification. Modeling inventor migration to West German regions after 1990, we find that Western regions with stronger historically determined social ties across the former East-West border attracted more inventors after the fall of the Iron Curtain than regions without...

  13. Analyzing negative ties in social networks

    Directory of Open Access Journals (Sweden)

    Mankirat Kaur

    2016-03-01

    Full Text Available Online social networks are a source of sharing information and maintaining personal contacts with other people through social interactions and thus forming virtual communities online. Social networks are crowded with positive and negative relations. Positive relations are formed by support, endorsement and friendship and thus, create a network of well-connected users whereas negative relations are a result of opposition, distrust and avoidance creating disconnected networks. Due to increase in illegal activities such as masquerading, conspiring and creating fake profiles on online social networks, exploring and analyzing these negative activities becomes the need of hour. Usually negative ties are treated in same way as positive ties in many theories such as balance theory and blockmodeling analysis. But the standard concepts of social network analysis do not yield same results in respect of each tie. This paper presents a survey on analyzing negative ties in social networks through various types of network analysis techniques that are used for examining ties such as status, centrality and power measures. Due to the difference in characteristics of flow in positive and negative tie networks some of these measures are not applicable on negative ties. This paper also discusses new methods that have been developed specifically for analyzing negative ties such as negative degree, and h∗ measure along with the measures based on mixture of positive and negative ties. The different types of social network analysis approaches have been reviewed and compared to determine the best approach that can appropriately identify the negative ties in online networks. It has been analyzed that only few measures such as Degree and PN centrality are applicable for identifying outsiders in network. For applicability in online networks, the performance of PN measure needs to be verified and further, new measures should be developed based upon negative clique concept.

  14. Coil-springs used as mechanical filter. Modification of the bottom tie plate of a fuel assembly

    International Nuclear Information System (INIS)

    Nylund, O.

    1993-01-01

    Describes an improved design of the bottom tie plate of a fuel assembly. The improvement of the design is an arrangement of horizontal channels holding coil-springs and crossing the vertical channels for the cooling water. The coil-springs work as strainers for the cooling water

  15. The effect of interaction topic and social ties on media choice and the role of four underlying mechanisms

    NARCIS (Netherlands)

    Croes, Emmelyn; Antheunis, Marjolijn; Schouten, Alexander; Krahmer, Emiel

    2018-01-01

    This study employed a scenario-based approach whereby participants were asked to choose which communication channel they prefer in certain situations. The first aim was to determine the effect of the topic of interactions and social ties on channel choice. The second aim was to examine the

  16. Disturbance legacies of historic tie-drives persistently alter geomorphology and large wood characteristics in headwater streams, southeast Wyoming

    Science.gov (United States)

    Claire M. Ruffing; Melinda D. Daniels; Kathleen A. Dwire

    2015-01-01

    Instream wood is recognized as an integral component of stream morphology in forested areas. However, few studies have evaluated the legacy effects of historic wood removal activities and associated impacts on channel morphology, contemporary wood loading, and recruitment. This study investigates the role of historic tie-driving, a widespread channel disturbance legacy...

  17. The power of indirect social ties

    OpenAIRE

    Zuo, Xiang; Blackburn, Jeremy; Kourtellis, Nicolas; Skvoretz, John; Iamnitchi, Adriana

    2014-01-01

    While direct social ties have been intensely studied in the context of computer-mediated social networks, indirect ties (e.g., friends of friends) have seen little attention. Yet in real life, we often rely on friends of our friends for recommendations (of good doctors, good schools, or good babysitters), for introduction to a new job opportunity, and for many other occasional needs. In this work we attempt to 1) quantify the strength of indirect social ties, 2) validate it, and 3) empiricall...

  18. Construction loads experienced by plastic composite ties.

    Science.gov (United States)

    2014-07-01

    Damage to plastic composite ties during handling and track installation has been reported by a number of railroads. Results from : a survey conducted to identify specific handling issues were used to develop field and laboratory tests to measure the ...

  19. Tying Trade Flows: A Theory of Countertrade

    OpenAIRE

    Marin, Dalia; Schnitzer, Monika

    1994-01-01

    A countertrade contract ties an export to an import. Usually, countertrade is seen as a form of bilateralism and reciprocity and thus as an inefficient form of international exchange. In this paper we argue that there are circumstances where the tying of two technologically unrelated trade flows may be efficiency enhancing. We show that countertrade can be seen as an efficient institution that solves moral hazard problems and restores creditworthiness of countries with large outstanding debt....

  20. The Strength of Weak Ties in MBA Job Search: A Within–Person Test

    Directory of Open Access Journals (Sweden)

    Jason Greenberg

    2016-05-01

    Full Text Available Whether and how social ties create value has inspired substantial research in organizational theory, sociology, and economics. Scholars generally believe that social ties impact labor market outcomes. Two explanatory mechanisms have been identified, emphasizing access to better job offers in pecuniary terms and the efficacy of non-redundant information. The evidence informing each theory, however, has been inconsistent and circumstantial. We test predictions from both models using a rich set of job search data collected from an MBA student population, including detailed information about search channels and characteristics of job offers. Importantly, we can compare offers made to the same student derived via different search channels while accounting for industry, function, and non-pecuniary characteristics. We find that contrary to conventional wisdom, search through social networks typically results in job offers with lower total compensation (-17 percent for referrals through strong ties and -16 percent for referrals via weak ties vs. formal search. However, our models also show that students are considerably more likely to accept offers derived via weak ties. They do so because they are perceived to have greater growth potential and other non-pecuniary value. On balance, our tests are consistent with Granovetter’s argument that networks provide value by facilitating access to information that is otherwise difficult to obtain, rather than providing greater pecuniary compensation.

  1. Geomorphic changes resulting from floods in reconfigured gravel-bed river channels in Colorado, USA

    Science.gov (United States)

    Elliott, J.G.; Capesius, J.P.

    2009-01-01

    Geomorphic changes in reconfi gured reaches of three Colorado rivers in response to floods in 2005 provide a benchmark for "restoration" assessment. Sedimententrainment potential is expressed as the ratio of the shear stress from the 2 yr, 5 yr, 10 yr, and 2005 floods to the critical shear stress for sediment. Some observed response was explained by the excess of flood shear stress relative to the resisting force of the sediment. Bed-load entrainment in the Uncompahgre River and the North Fork Gunnison River, during 4 and 6 yr floods respectively, resulted in streambed scour, streambed deposition, lateral-bar accretion, and channel migration at various locations. Some constructed boulder and log structures failed because of high rates of bank erosion or bed-material deposition. The Lake Fork showed little or no net change after the 2005 flood; however, this channel had not conveyed floods greater than the 2.5 yr flood since reconfi guration. Channel slope and the 2 yr flood, a surrogate for bankfull discharge, from all three reconfi gured reaches plotted above the Leopold and Wolman channel-pattern threshold in the "braided channel" region, indicating that braiding, rather than a single-thread meandering channel, and midchannel bar formation may be the natural tendency of these gravel-bed reaches. When plotted against a total stream-power and median-sediment-size threshold for the 2 yr flood, however, the Lake Fork plotted in the "single-thread channel" region, the North Fork Gunnison plotted in the " multiplethread" region, and the Uncompahgre River plotted on the threshold. All three rivers plotted in the multiple-thread region for floods of 5 yr recurrence or greater. ?? 2009 Geological Society of America.

  2. Software With Strong Ties to Space

    Science.gov (United States)

    2003-01-01

    TieFlow is a simple but powerful business process improvement solution. It can automate and simplify any generic or industry-specific work process, helping organizations to transform work inefficiencies and internal operations involving people, paper, and procedures into a streamlined, well-organized, electronicbased process. TieFlow increases business productivity by improving process cycle times. The software can expedite generic processes in the areas of product design and development, purchase orders, expense reports, benefits enrollment, budgeting, hiring, and sales. It can also shore up vertical market processes such as claims processing, loan application and processing, health care administration, contract management, and advertising agency traffic. The processes can be easily and rapidly captured in a graphical manner and enforced together with rules pertaining to assignments that need to be performed. Aside from boosting productivity, TieFlow also reduces organizational costs and errors. TieFlow was developed with Small Business Innovation Research (SBIR) assistance from Johnson. The SBIR support entitles all Federal Government agencies to utilize the TieFlow software technology free of charge. Tietronix emphasizes that TieFlow is an outstanding workflow resource that could produce dramatic productivity and cost improvements for all agencies, just as it has done and continues to do for NASA. The Space Agency is currently using the software throughout several mission-critical offices, including the Mission Operations Directorate and the Flight Director s Office, for worldwide participation of authorized users in NASA processes. At the Flight Director s Office, TieFlow allows personnel to electronically submit and review changes to the flight rules carried out during missions.

  3. Analysis of ICPP fuel storage rack inner tie and corner tie substructures

    Energy Technology Data Exchange (ETDEWEB)

    Nitzel, M.E.; Rahl, R.G.

    1996-01-01

    Finite element models were developed and analyses performed for the tie plate, inner tie block assembly, and corner tie block assembly of a 25 port fuel rack assembly designed for installation in Pool 1 of Building 666 at the Idaho Chemical Processing Plant. These models were specifically developed to investigate the adequacy of certain welds joining components of the fuel storage rack assembly. The work scope for the task was limited to an investigation of the stress levels in the subject subassemblies when subjected to seismic loads. Structural acceptance criteria used for the elastic calculations performed were as found in the overall rack design report as issued by the rack`s designer, Holtec International. Structural acceptance criteria used for the plastic calculations performed as part of this effort were as defined in Subsection NF and Appendix F of the ASME Boiler & Pressure Vessel Code. The results of the analyses will also apply to the 30 port fuel storage rack design that is also scheduled for installation in Pool 1 of ICPP 666. The results obtained from the analyses performed for this task indicate that the welds joining the inner tie block and corner tie block to the surrounding rack structure meet the acceptance criteria. Further, the structural members (plates and blocks) were also found to be within the allowable stress limits established by the acceptance criteria. The separate analysis performed on the inner tie plate confirmed the structural adequacy for both the inner tie plate, corner tie plate, and tie block bolts. The analysis results verified that the inner tie and corner tie block should be capable of transferring the expected seismic load without structural failure.

  4. Open knot-tying skills: residents skills assessed

    NARCIS (Netherlands)

    van Empel, P.J.; Verdam, M.G.E.; Huirne, J.A.; Bonjer, H.J.; Meijerink, W.J.; Scheele, F.

    2013-01-01

    Aim: Open knot-tying and suturing skills are fundamental surgical skills, founding many alternative knot-tying techniques. It is therefore mandatory for residents to possess adequate basic open knot-tying skills. The aim of this study was to compare an objective assessment of open knot-tying skills

  5. TIE: An Ability Test of Emotional Intelligence

    Science.gov (United States)

    Śmieja, Magdalena; Orzechowski, Jarosław; Stolarski, Maciej S.

    2014-01-01

    The Test of Emotional Intelligence (TIE) is a new ability scale based on a theoretical model that defines emotional intelligence as a set of skills responsible for the processing of emotion-relevant information. Participants are provided with descriptions of emotional problems, and asked to indicate which emotion is most probable in a given situation, or to suggest the most appropriate action. Scoring is based on the judgments of experts: professional psychotherapists, trainers, and HR specialists. The validation study showed that the TIE is a reliable and valid test, suitable for both scientific research and individual assessment. Its internal consistency measures were as high as .88. In line with theoretical model of emotional intelligence, the results of the TIE shared about 10% of common variance with a general intelligence test, and were independent of major personality dimensions. PMID:25072656

  6. Inferring tie strength from online directed behavior.

    Directory of Open Access Journals (Sweden)

    Jason J Jones

    Full Text Available Some social connections are stronger than others. People have not only friends, but also best friends. Social scientists have long recognized this characteristic of social connections and researchers frequently use the term tie strength to refer to this concept. We used online interaction data (specifically, Facebook interactions to successfully identify real-world strong ties. Ground truth was established by asking users themselves to name their closest friends in real life. We found the frequency of online interaction was diagnostic of strong ties, and interaction frequency was much more useful diagnostically than were attributes of the user or the user's friends. More private communications (messages were not necessarily more informative than public communications (comments, wall posts, and other interactions.

  7. TIE: an ability test of emotional intelligence.

    Science.gov (United States)

    Śmieja, Magdalena; Orzechowski, Jarosław; Stolarski, Maciej S

    2014-01-01

    The Test of Emotional Intelligence (TIE) is a new ability scale based on a theoretical model that defines emotional intelligence as a set of skills responsible for the processing of emotion-relevant information. Participants are provided with descriptions of emotional problems, and asked to indicate which emotion is most probable in a given situation, or to suggest the most appropriate action. Scoring is based on the judgments of experts: professional psychotherapists, trainers, and HR specialists. The validation study showed that the TIE is a reliable and valid test, suitable for both scientific research and individual assessment. Its internal consistency measures were as high as .88. In line with theoretical model of emotional intelligence, the results of the TIE shared about 10% of common variance with a general intelligence test, and were independent of major personality dimensions.

  8. TIE: an ability test of emotional intelligence.

    Directory of Open Access Journals (Sweden)

    Magdalena Śmieja

    Full Text Available The Test of Emotional Intelligence (TIE is a new ability scale based on a theoretical model that defines emotional intelligence as a set of skills responsible for the processing of emotion-relevant information. Participants are provided with descriptions of emotional problems, and asked to indicate which emotion is most probable in a given situation, or to suggest the most appropriate action. Scoring is based on the judgments of experts: professional psychotherapists, trainers, and HR specialists. The validation study showed that the TIE is a reliable and valid test, suitable for both scientific research and individual assessment. Its internal consistency measures were as high as .88. In line with theoretical model of emotional intelligence, the results of the TIE shared about 10% of common variance with a general intelligence test, and were independent of major personality dimensions.

  9. Application of ELJ to create and maintain side channels in a dynamic gravel bed river

    Science.gov (United States)

    Crabbe, E.; Crowe Curran, J.; Ockelford, A.

    2017-12-01

    Braided and anastomosing rivers create and maintain a large amount of side channel habitat. Unfortunately, many rivers that were once multi-channel rivers have been constrained to single thread channels as a consequence of land use changes that occurred in the 19th and 20th centuries or earlier. An increasingly common management goal today is the re-creation of self-maintaining side and tributary habitat through as natural means as possible. This work examines the geomorphic history of one such channel and the success of recent rehabilitation efforts. Our case study comes from the South Fork Nooksack River in the Cascades Range in Washington State. The Nooksack River is a gravel and sand bed channel with a snowmelt dominated hydrograph. Engineered log jams (ELJ) have been employed to direct flow into side and chute channels with the larger goals of increasing overall channel complexity and salmon spawning opportunities. ELJs have been constructed on the channel since the 2000s, and the ELJs in the study reaches range in age up to 10 years. The size and design of individual jams within the reach vary, enabling a comparison between jam types. ELJs are evaluated for their ability to maintain gravel bar locations and open tributary channels through the snowmelt season over the reach scale. Additional goals of trapping wood onto the jams and existing bars, stabilizing channel banks, and allowing for the growth of bar vegetation are also examined.

  10. Relationships: The Critical Ties That Bind Professionals.

    Science.gov (United States)

    Roper, Larry

    2002-01-01

    This article proposes that the success of student affairs professionals is more closely tied to their ability to construct and manage essential relationships during their careers than any other activity. The author discusses essential principles and skills in developing and managing professional relationships. (GCP)

  11. Weizmann ties with Cambridge in physics contest

    CERN Multimedia

    Siegel, J

    2004-01-01

    "Scientists and students from the Weizmann Institute of Science in Rehovot and Cambridge University in England have tied for first place in a physics competition aimed at simulating the future functioning of the particle accelerator being built at the European center CERN and due to open in 2007" (1/2 page)

  12. Silicon-on-insulator field effect transistor with improved body ties for rad-hard applications

    Science.gov (United States)

    Schwank, James R.; Shaneyfelt, Marty R.; Draper, Bruce L.; Dodd, Paul E.

    2001-01-01

    A silicon-on-insulator (SOI) field-effect transistor (FET) and a method for making the same are disclosed. The SOI FET is characterized by a source which extends only partially (e.g. about half-way) through the active layer wherein the transistor is formed. Additionally, a minimal-area body tie contact is provided with a short-circuit electrical connection to the source for reducing floating body effects. The body tie contact improves the electrical characteristics of the transistor and also provides an improved single-event-upset (SEU) radiation hardness of the device for terrestrial and space applications. The SOI FET also provides an improvement in total-dose radiation hardness as compared to conventional SOI transistors fabricated without a specially prepared hardened buried oxide layer. Complementary n-channel and p-channel SOI FETs can be fabricated according to the present invention to form integrated circuits (ICs) for commercial and military applications.

  13. Performance evaluation of concrete railroad ties on the northeast corridor.

    Science.gov (United States)

    2014-03-01

    Simpson Gumpertz & Heger Inc. conducted an investigation into the factors that caused widespread failure in prestressed concrete : railroad ties on the Northeast Corridor. The problem was apparent in ties manufactured and installed circa 19941998....

  14. Freeze-thaw performance testing of whole concrete railroad ties.

    Science.gov (United States)

    2013-10-01

    Freezing and thawing durability tests of prestressed concrete ties are normally performed according to ASTM C666 specifications. Small specimens are cut from the shoulders of concrete ties and tested through 300 cycles of freezing and thawing. Saw-cu...

  15. Network ties in the international opportunity recognition of family SMEs

    OpenAIRE

    Kontinen, Tanja; Ojala, Arto

    2011-01-01

    The importance of network ties is emphasized in the current literature on opportunity recognition. However, it is unclear how firms with limited bridging networks, such as family SMEs, recognize international opportunities through their network ties. In this case study we found that in gaining foreign market entry, those family SMEs that lack existing network ties recognize opportunities through weak ties formed in international exhibitions. The findings also indicate that rather than being p...

  16. Nonlinear Price Schedules and Tied Products.

    OpenAIRE

    Ormiston, Michael B; Phillips, Owen R

    1988-01-01

    Illegal tying often occurs when a monopolist jointly sells a product with a complementary requirement, also sold competitively. Along with selling the complement at its competi tive price, this paper shows that profit can increase when a monopoli st lets consumers bundle any amount of the requirement with the basic product at a fixed price. Examples illustrate demand conditions that enhance the profitability of this nonlinear price strategy and show that profits can approximate those earned f...

  17. China, Argentina agree to further strategic ties

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    According to Xinhua,China and Argentina have agreed to further enhance mutual trust and their strategic partnership as the two emerging economies are playing an increasingly important role in the world arena.“China will work with Argentina to strengthen strategic mutual trust,expand cooperation and coordination within multilateral frameworks in order to promote bilateral ties and benefit the two peoples,” Vice President Xi Jinping told Argentine Foreign Minister Hector Timerman on September 9.

  18. Grid-Tied Photovoltaic Power System

    Science.gov (United States)

    Eichenberg, Dennis J.

    2011-01-01

    A grid-tied photovoltaic (PV) power system is connected directly to the utility distribution grid. Facility power can be obtained from the utility system as normal. The PV system is synchronized with the utility system to provide power for the facility, and excess power is provided to the utility. Operating costs of a PV power system are low compared to conventional power technologies. This method can displace the highest-cost electricity during times of peak demand in most climatic regions, and thus reduce grid loading. Net metering is often used, in which independent power producers such as PV power systems are connected to the utility grid via the customers main service panels and meters. When the PV power system is generating more power than required at that location, the excess power is provided to the utility grid. The customer pays the net of the power purchased when the on-site power demand is greater than the onsite power production, and the excess power is returned to the utility grid. Power generated by the PV system reduces utility demand, and the surplus power aids the community. Modern PV panels are readily available, reliable, efficient, and economical, with a life expectancy of at least 25 years. Modern electronics have been the enabling technology behind grid-tied power systems, making them safe, reliable, efficient, and economical with a life expectancy equal to the modern PV panels. The grid-tied PV power system was successfully designed and developed, and this served to validate the basic principles developed, and the theoretical work that was performed. Grid-tied PV power systems are reliable, maintenance- free, long-life power systems, and are of significant value to NASA and the community. Of particular value are the analytical tools and capabilities that have been successfully developed. Performance predictions can be made confidently for grid-tied PV systems of various scales. The work was done under the NASA Hybrid Power Management (HPM

  19. Vínculos organizacionais Organizational ties

    Directory of Open Access Journals (Sweden)

    Gustavo Garcez Kramer

    2007-02-01

    Full Text Available Este artigo é um estudo de caso único, realizado junto a uma organização pública municipal de Curitiba, e tem como objetivo investigar e compreender os vínculos organizacionais. O estudo dos vínculos é feito por meio dos seus elementos constitutivos: a identificação, o sentimento de pertença, a cooperação, a participação, a criação de inimigos, a idealização, o reconhecimento e valorização dos indivíduos, a solidariedade, a integração, o crescimento e desenvolvimento pessoal e profissional e a autonomia. Foram utilizados, como instrumentos de coleta, questionário fechado e análise documental. O resultado dessa pesquisa é a caracterização dos elementos que são importantes na formação e manutenção dos vínculos e, conseqüentemente, para o comprometimento dos empregados com os objetivos, políticas, problemas, desempenho e resultados da organização.This article presents a unique case study of the organizational ties in a public municipal organization in the city of Curitiba, Brazil. The ties are studied through their constitutive elements: identification, sense of belonging, cooperation, participation, creation of enemies, idealization, recognition and appreciation of individuals, solidarity, integration, professional and personal development and growth, and autonomy. Documental analysis and closed questionnaires were used for data collection. The research resulted in the characterization of the elements that are important in making and keeping ties, and consequently committing employees to the organization's objectives, policies, problems, performance and results.

  20. The Running Barbed Tie-over Dressing.

    Science.gov (United States)

    Joyce, Cormac W; Joyce, Kenneth M; Kennedy, Ann-Marie; Kelly, Jack L

    2014-04-01

    Barbed suture technology is becoming increasingly popular in plastic surgery and is now being used in body contouring surgery and facial rejuvenation. We describe the novel application of a barbed suture as a running tie-over dressing for skin grafts. The barbs act as anchors in the skin, so constant tensioning of the suture is not required. The bidirectional nature of the suture prevents any slippage, and the barbs even act as a grip on the underlying wool dressing. Furthermore, the method described is both quick and simple to learn and would be useful for the sole operator.

  1. The Running Barbed Tie-over Dressing

    Directory of Open Access Journals (Sweden)

    Cormac W. Joyce, MB, BCh, MRCSI

    2014-04-01

    Full Text Available Summary: Barbed suture technology is becoming increasingly popular in plastic surgery and is now being used in body contouring surgery and facial rejuvenation. We describe the novel application of a barbed suture as a running tie-over dressing for skin grafts. The barbs act as anchors in the skin, so constant tensioning of the suture is not required. The bidirectional nature of the suture prevents any slippage, and the barbs even act as a grip on the underlying wool dressing. Furthermore, the method described is both quick and simple to learn and would be useful for the sole operator.

  2. Strong Ties, Weak Ties, and Human Capital: Latino Immigrant Employment outside the Enclave

    Science.gov (United States)

    Pfeffer, Max J.; Parra, Pilar A.

    2009-01-01

    This study focuses on the role of social ties and human capital in the integration of Latino immigrants into the local economy. This analysis extends earlier research by focusing on more rural contexts with limited labor-market opportunities and less access to social resources provided by coethnics. We reconsider conclusions of previous studies by…

  3. Historical perspectives on channel pattern in the Clark Fork River, Montana and implications for post-dam removal restoration

    Science.gov (United States)

    Woelfle-Erskine, C. A.; Wilcox, A. C.

    2009-12-01

    Active restoration approaches such as channel reconstruction have moved beyond the realm of small streams and are being applied to larger rivers. Uncertainties arising from limited knowledge, fluvial and ecosystem variability, and contaminants are especially significant in restoration of large rivers, where project costs and the social, infrastructural, and ecological costs of failure are high. We use the case of Milltown Dam removal on the Clark Fork River, Montana and subsequent channel reconstruction in the former reservoir to examine the use of historical research and uncertainty analysis in river restoration. At a cost of approximately $120 million, the Milltown Dam removal involves the mechanical removal of approximately 2 million cubic meters of sediments contaminated by upstream mining, followed by restoration of the former reservoir reach in which a single-thread meandering channel is being constructed. Historical maps, surveys, photographs, and accounts suggest a conceptual model of a multi-thread, anastomosing river in the reach targeted for channel reconstruction, upstream of the confluence of the Clark Fork and Blackfoot Rivers. We supplemented historical research with analysis of aerial photographs, topographic data, and USGS stage-discharge measurements in a lotic but reservoir-influenced reach of the Clark Fork River within our study area to estimate avulsion frequency (0.8 avulsions/year over a 70-year period) and average rates of lateral migration and aggradation. These were used to calculate the mobility number, a dimensionless relationship between channel filling and lateral migration timescales that can be used to predict whether a river’s planform is single or multi-threaded. The mobility number within our study reach ranged from 0.6 (multi-thread channel) to 1.7 (transitional channel). We predict that, in the absence of active channel reconstruction, the post-dam channel pattern would evolve to one that alternates between single and multi

  4. Parallel channel effects under BWR LOCA conditions

    International Nuclear Information System (INIS)

    Suzuki, H.; Hatamiya, S.; Murase, M.

    1988-01-01

    Due to parallel channel effects, different flow patterns such as liquid down-flow and gas up-flow appear simultaneously in fuel bundles of a BWR core during postulated LOCAs. Applying the parallel channel effects to the fuel bundle, water drain tubes with a restricted bottom end have been developed in order to mitigate counter-current flow limiting and to increase the falling water flow rate at the upper tie plate. The upper tie plate with water drain tubes is an especially effective means of increasing the safety margin of a reactor with narrow gaps between fuel rods and high steam velocity at the upper tie plate. The characteristics of the water drain tubes have been experimentally investigated using a small-scaled steam-water system simulating a BWR core. Then, their effect on the fuel cladding temperature was evaluated using the LOCA analysis program SAFER. (orig.)

  5. A Multi-Dimensional Heat Transfer Model of a Tie-Tube and Hexagonal Fuel Element for Nuclear Thermal Propulsion

    Science.gov (United States)

    Gomez, C. F.; Mireles, O. R.; Stewart, E.

    2016-01-01

    The Space Capable Cryogenic Thermal Engine (SCCTE) effort considers a nuclear thermal rocket design based around a Low-Enriched Uranium (LEU) design fission reactor. The reactor core is comprised of bundled hexagonal fuel elements that directly heat hydrogen for expansion in a thrust chamber and hexagonal tie-tubes that house zirconium hydride moderator mass for the purpose of thermalizing fast neutrons resulting from fission events. Created 3D steady state Hex fuel rod model with 1D flow channels. Hand Calculation were used to set up initial conditions for fluid flow. The Hex Fuel rod uses 1D flow paths to model the channels using empirical correlations for heat transfer in a pipe. Created a 2-D axisymmetric transient to steady state model using the CFD turbulent flow and Heat Transfer module in COMSOL. This model was developed to find and understand the hydrogen flow that might effect the thermal gradients axially and at the end of the tie tube where the flow turns and enters an annulus. The Hex fuel rod and Tie tube models were made based on requirements given to us by CSNR and the SCCTE team. The models helped simplify and understand the physics and assumptions. Using pipe correlations reduced the complexity of the 3-D fuel rod model and is numerically more stable and computationally more time-efficient compared to the CFD approach. The 2-D axisymmetric tie tube model can be used as a reference "Virtual test model" for comparing and improving 3-D Models.

  6. Reciprocity, social ties, and competition in markets for experience goods

    DEFF Research Database (Denmark)

    Huck, Steffen; Tyran, Jean-Robert

    2007-01-01

    a positive externality for non-reciprocal customers who would, in the absence of reciprocal types, face market breakdown. This efficiency-enhancing effect of reciprocity is boosted when there are social ties between consumers and competition between firms. The existence of social ties or competition alone...

  7. Employees and Creativity: Social Ties and Access to Heterogeneous Knowledge

    Science.gov (United States)

    Huang, Chiung-En; Liu, Chih-Hsing Sam

    2015-01-01

    This study dealt with employee social ties, knowledge heterogeneity contacts, and the generation of creativity. Although prior studies demonstrated a relationship between network position and creativity, inadequate attention has been paid to network ties and heterogeneity knowledge contacts. This study considered the social interaction processes…

  8. Evolution of bow-tie architectures in biology.

    Directory of Open Access Journals (Sweden)

    Tamar Friedlander

    2015-03-01

    Full Text Available Bow-tie or hourglass structure is a common architectural feature found in many biological systems. A bow-tie in a multi-layered structure occurs when intermediate layers have much fewer components than the input and output layers. Examples include metabolism where a handful of building blocks mediate between multiple input nutrients and multiple output biomass components, and signaling networks where information from numerous receptor types passes through a small set of signaling pathways to regulate multiple output genes. Little is known, however, about how bow-tie architectures evolve. Here, we address the evolution of bow-tie architectures using simulations of multi-layered systems evolving to fulfill a given input-output goal. We find that bow-ties spontaneously evolve when the information in the evolutionary goal can be compressed. Mathematically speaking, bow-ties evolve when the rank of the input-output matrix describing the evolutionary goal is deficient. The maximal compression possible (the rank of the goal determines the size of the narrowest part of the network-that is the bow-tie. A further requirement is that a process is active to reduce the number of links in the network, such as product-rule mutations, otherwise a non-bow-tie solution is found in the evolutionary simulations. This offers a mechanism to understand a common architectural principle of biological systems, and a way to quantitate the effective rank of the goals under which they evolved.

  9. 27 CFR 6.72 - “Tie-in” sales.

    Science.gov (United States)

    2010-04-01

    ... OF THE TREASURY LIQUORS âTIED-HOUSEâ Unlawful Inducements Quota Sales § 6.72 “Tie-in” sales. The act by an industry member of requiring that a retailer purchase one product (as defined in § 6.11) in... and not individually. However, an industry member is not precluded from selling two or more kinds or...

  10. The Strength of the Strongest Ties in Collaborative Problem Solving

    DEFF Research Database (Denmark)

    de Montjoye, Yves-Alexandre; Stopczynski, Arkadiusz; Shmueli, Erez

    2014-01-01

    an effect on performance. Both networks of strong ties explain more of the variance than other factors, such as measured or self-evaluated technical competencies, or the personalities of the team members. In fact, the inclusion of the network of strong ties renders these factors non...

  11. Tie-breaking in games of perfect information

    DEFF Research Database (Denmark)

    Tranæs, Torben

    1998-01-01

    The paper suggests that ties in an extensive form game have strategic implications if they represent credible threats or promises. We consider a subset of subgame-perfect Nash equilibria obtained by breaking ties according to their strategic implications, and show that the subset is nonempty for ...

  12. Multicentre randomised double bind crossover trial on contamination of conventional ties and bow ties in routine obstetric and gynaecological practice.

    Science.gov (United States)

    Biljan, M M; Hart, C A; Sunderland, D; Manasse, P R; Kingsland, C R

    1993-01-01

    OBJECTIVE--To assess level of contamination of neckwear worn by gynaecologists and obstetricians during routine working week. DESIGN--Multicentre randomised double blind crossover trial. Participants wore the same conventional ties for three days in one week and bow ties for the same period in second week. SETTING--Two teaching and three district general hospitals in the midlands, Wales, and north England. SUBJECTS--15 registrars and senior registrars. INTERVENTIONS--A swab soaked in sterile saline was taken from specific area on ties at end of first and third working days and sent in transport medium for culture on chocolatised blood and MacConkey agar for 48 hours. MAIN OUTCOME MEASURES--Level of bacteriological growth assessed semiquantitatively (0 for no contamination; for heavy contamination) after swabs had been cultured. At end of study the participants completed a questionnaire to assess their attitude toward wearing different types of necktie. RESULTS--12 doctors (80%) completed the study. Although bow ties were significantly less contaminated at end of first working day (z = -2.354, p = 0.019), this difference was not maintained; there was no difference in level of contamination on third day. Level of contamination did not increase between first and third day of wearing the same garment. One of the 10 doctors who returned the questionnaire found the bow tie very uncomfortable. All participants would consider wearing a bow tie if it proved to be less contaminated than a conventional tie. CONCLUSIONS--Although a significant difference in contamination was established between conventional and bow ties on first day of study, this difference was not confirmed on third day and there is unlikely to be any real association between tie type and bacterial contamination. Because of its negative image and difficulty to tie, the bow tie will probably remain a minority fashion. Images p1583-a PMID:8292945

  13. Redoable Tie-Over Dressing Using Multiple Loop Silk Threads

    Directory of Open Access Journals (Sweden)

    Hyeon Jong Jo

    2013-05-01

    Full Text Available After skin grafting, to prevent hematoma or seroma collection at the graft site, a tie-over dressing has been commonly used. However, although the conventional tie-over dressing by suture is a useful method for securing a graft site, refixation is difficult when repeated tie-over dressing is needed. Therefore, we recommend a redoable tie-over dressing technique with multiple loops threads and connecting silk threads. After the raw surface of each of our cases was covered with a skin graft, multiple loop silk thread attached with nylon at the skin graft margin. We applied the ointment gauze and wet cotton/fluffy gauze over the skin graft, then fixed the dressing by connecting cross-counter multiple loop thread with connecting silk threads. When we opened the tie-over dressing by cutting the connecting silk threads, we repeated the tie-over dressing with the same method. The skin graft was taken successfully without hematoma or seroma collection or any other complications. In conclusion, we report a novel tie-over dressing enabling simple fixation of the dressing to maintain proper tension for wounds that require repetitive fixation. Further, with this reliable method, the skin grafts were well taken.

  14. Tyrosine phosphorylation of Grb14 by Tie2

    Directory of Open Access Journals (Sweden)

    Dumont Daniel J

    2010-10-01

    Full Text Available Abstract Background Growth factor receptor bound (Grb proteins 7, 10 and 14 are a family of structurally related multi-domain adaptor proteins involved in a variety of biological processes. Grb7, 10 and 14 are known to become serine and/or threonine phosphorylated in response to growth factor (GF stimulation. Grb7 and 10 have also been shown to become tyrosine phosphorylated under certain conditions. Under experimental conditions Grb7 is tyrosine phosphorylated by the Tie2/Tie-2/Tek angiogenic receptor tyrosine kinase (RTK. Furthermore, Grb14 has also been shown to interact with Tie2, however tyrosine phosphorylation of this Grb family member has yet to be reported. Results Here we report for the first time tyrosine phosphorylation of Grb14. This phosphorylation requires a kinase competent Tie2 as well as intact tyrosines 1100 and 1106 (Y1100 and Y1106 on the receptor. Furthermore, a complete SH2 domain on Grb14 is required for Grb14 tyrosine phosphorylation by Tie2. Grb14 was also able to become tyrosine phosphorylated in primary endothelial cells when treated with a soluble and potent variant of the Tie2 ligand, cartilage oligomeric matrix protein (COMP Ang1. Conclusion Our results show that Grb14, like its family members Grb7 and Grb10, is able to be tyrosine phosphorylated. Furthermore, our data indicate a role for Grb14 in endothelial signaling downstream of the Tie2 receptor.

  15. The Popularity of Picture Books with Television Tie-in

    Directory of Open Access Journals (Sweden)

    Patricia R. Ladd

    2011-06-01

    Full Text Available This study analyzes circulation statistics of television tie-in picture books from the Wake County Public Library System in North Carolina to determine their popularity among patrons. Caldecott winning picture books were used as a point of comparison. This study also examined OPAC holdings from North Carolina public libraries to determine television tie-in picture book popularity among collection builders. The findings of the study show that television tie-in picture books are found to some degree in the vast majority of North Carolina public libraries, and are more popular than award winners in the Wake County system.

  16. The social tie and the malaise facing the helplessness

    Directory of Open Access Journals (Sweden)

    Cristina Aparecida Tannure Cavalcanti

    2015-12-01

    Full Text Available In this article we intend to approach the discourses as social ties, indicated by Lacan, relating them to the freudian concepts of helplessness (Hilflosigkeit and the malaise of civilization. The theory of discourses opens up a new way of thinking about clinical structures and social ties, by articulating language and enjoyment camps, the subject and the unconscious knowledge. This theory, while it takes over Freudian principles, it advances in impasses left by the Viennese master, in particular on the relationship between the metapsychological foundations of the subjective constitution and the conceptual bases concerning culture and actual social ties.

  17. EXPORT PROMOTION: Export-Import Bank and Treasury Differ in Their Approaches to Using Tied Aid

    National Research Council Canada - National Science Library

    2002-01-01

    Under the tied aid program legislation,4 Treasury had the authority to direct and control the use of Ex-Im Bank's Tied Aid Capital Projects Fund, in effect allowing Treasury to veto individual tied aid proposals...

  18. River banks and channel axis curvature: Effects on the longitudinal dispersion in alluvial rivers

    Science.gov (United States)

    Lanzoni, Stefano; Ferdousi, Amena; Tambroni, Nicoletta

    2018-03-01

    The fate and transport of soluble contaminants released in natural streams are strongly dependent on the spatial variations of the flow field and of the bed topography. These variations are essentially related to the presence of the channel banks and to the planform configuration of the channel. Large velocity gradients arise near to the channel banks, where the flow depth decreases to zero. Moreover, single thread alluvial rivers are seldom straight, and usually exhibit meandering planforms and a bed topography that deviates from the plane configuration. Channel axis curvature and movable bed deformations drive secondary helical currents which enhance both cross sectional velocity gradients and transverse mixing, thus crucially influencing longitudinal dispersion. The present contribution sets up a rational framework which, assuming mild sloping banks and taking advantage of the weakly meandering character often exhibited by natural streams, leads to an analytical estimate of the contribution to longitudinal dispersion associated with spatial non-uniformities of the flow field. The resulting relationship stems from a physics-based modeling of the flow in natural rivers, and expresses the bend averaged longitudinal dispersion coefficient as a function of the relevant hydraulic and morphologic parameters. The treatment of the problem is river specific, since it relies on an explicit spatial description, although linearized, of the flow field that establishes in the investigated river. Comparison with field data available from tracer tests supports the robustness of the proposed framework, given also the complexity of the processes that affect dispersion dynamics in real streams.

  19. Social network ties beyond nonredundancy: an experimental investigation of the effect of knowledge content and tie strength on creativity.

    Science.gov (United States)

    Perry-Smith, Jill E

    2014-09-01

    Social network research emphasizes the access to nonredundant knowledge content that network ties provide. I suggest that some content is more beneficial than others and that tie strength may affect creativity for reasons other than the associated structure. That is, tie strength may affect how individuals process nonredundant knowledge. I investigate 2 types of knowledge content--information (i.e., facts or data) and frames (i.e., interpretations or impressions)--and explore whether tie strength influences their effect on creativity. Drawing on creativity theory, I employ an experimental design to provide greater theoretical clarity and to isolate causality. According to the results from 2 studies, distinct frames received from contacts facilitate creativity, but the effect of distinct information is more complex. When individuals receive distinct information from strong ties, it constrains creativity compared to distinct frames. Content from weak ties appears to facilitate creativity across all scenarios. The results of mediated moderation analysis indicate the effect of framing versus information for strong ties is driven by decision-making time, as an indicator of cognitive expansion. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  20. Channel Evolution Following Avulsion: an Example from the Yellow River Delta

    Science.gov (United States)

    Zheng, S.

    2017-12-01

    Long-term field observation of morphological adjustments of rivers following avulsions is lacked when studying the evolution of avulsive channel on deltas. Avulsion at the Yellow River Delta (YRD) is frequent with average lifespan of channels of only about a decade. The Qing-shui-gou channel, the recent lobe on the YRD, provides a rare opportunity for investigating channel evolution following artificial avulsion. The reasons for its longer lifespan also needs investigation of the channel evolution. In this study, we comprehensively analyzed the geomorphic adjustment of the channel based on filed survey data during 1976-2014. The evolution of the channel was impacted by anthropogenic activities, including artificial avulsion at the downstream channel reaches in 1996, alteration of runoff and sediment load through Water and Sediment Regulation Scheme (WSRS), construction of levees and dikes. Analysis on channel geometry showed that avulsions in 1976 and in 1996 both caused short-term (1 2 years) erosion at the upstream channel reaches. Following the avulsion in 1976, massive aggradation occurred at the channel reaches at the downstream of the avulsion point. A single-thread channel gradually formed, widened and enlarged as channel bed under-cut on the deposition material. As delta extended seaward and the longitudinal slope decreased with time, aggradation occurred and an alluvial ridge formed. The ratio of lateral slope to the longitudinal slope (i.e. gradient advantage) and the relative super-elevation of the channel were calculated to estimate the possibility of avulsion at the channel in the late 1990. Results showed that the slope ratio was greater than 20 locally and super-elevation near its critical value for avulsion. The fact, that natural avulsion did not occurred despite of high values of gradient advantage and super elevation, may indicate that they are not sufficient conditions for avulsion at highly human-controlled rivers, where channel boundaries are

  1. Differentiating weak ties and strong ties among external sources of influences for enterprise resource planning (ERP) adoption

    Science.gov (United States)

    Aubert, Benoit; Léger, Pierre-Majorique; Larocque, Denis

    2012-05-01

    Enterprise resource planning (ERP) systems represent a major IT adoption decision. ERP adoption decisions, in the chemicals and allied products sectors, were examined between 1994 and 2005. Networks of strong ties and weak ties partners are investigated. Results show that neighbouring companies linked with strong ties can have an influence on organisations making such adoption decision. Past decisions made by major trading partners have a significant influence on the decision to adopt an ERP system for a given organisation. This reflects the complex nature of the knowledge required for such adoption.

  2. High-speed passenger rail tie-ballast interaction.

    Science.gov (United States)

    2015-05-01

    This Research Results Report presents : evidence of poor tie support and increased : applied loads that were used to determine the : root cause of transient and permanent vertical : displacements at two Amtrak bridge transitions. : These result...

  3. Cracking and impact performance characteristics of plastic composite ties.

    Science.gov (United States)

    2012-03-01

    As followup to a workshop on Engineered Composite Ties sponsored by the American Railway Engineering and Maintenance-of-Way Association and the Federal Railroad Administration, the Transportation Technology Center, Inc., in Pueblo, CO, conducted a se...

  4. The Strength of the Strongest Ties in Collaborative Problem Solving

    DEFF Research Database (Denmark)

    de Montjoye, Yves-Alexandre; Stopczynski, Arkadiusz; Shmueli, Erez

    2014-01-01

    Complex problem solving in science, engineering, and business has become a highly collaborative endeavor. Teams of scientists or engineers collaborate on projects using their social networks to gather new ideas and feedback. Here we bridge the literature on team performance and information networks...... by studying teams' problem solving abilities as a function of both their within-team networks and their members' extended networks. We show that, while an assigned team's performance is strongly correlated with its networks of expressive and instrumental ties, only the strongest ties in both networks have...... an effect on performance. Both networks of strong ties explain more of the variance than other factors, such as measured or self-evaluated technical competencies, or the personalities of the team members. In fact, the inclusion of the network of strong ties renders these factors non...

  5. DO TIE LABORATORY BASED ASSESSMENT METHODS REALLY PREDICT FIELD EFFECTS?

    Science.gov (United States)

    Sediment Toxicity Identification and Evaluation (TIE) methods have been developed for both porewaters and whole sediments. These relatively simple laboratory methods are designed to identify specific toxicants or classes of toxicants in sediments; however, the question of whethe...

  6. DO TIE LABORATORY BASED METHODS REALLY REFLECT FIELD CONDITIONS

    Science.gov (United States)

    Sediment Toxicity Identification and Evaluation (TIE) methods have been developed for both interstitial waters and whole sediments. These relatively simple laboratory methods are designed to identify specific toxicants or classes of toxicants in sediments; however, the question ...

  7. Older women play predominant role in building social ties and ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2016-08-03

    Aug 3, 2016 ... Older women play predominant role in building social ties and preventing ... brief demonstrates their contribution to building social cohesion and driving ... From learning to policy-oriented research: Lessons from South Africa's ...

  8. When community ties lead to violent crimes | IDRC - International ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2017-10-20

    Oct 20, 2017 ... Exploring social cohesion and mistrust of the state as drivers of urban ... Evidence suggests that these ties help communities to self-organize and .... acts while weakening social interactions and bonds between neighbours.

  9. Vibration Analysis for Monitoring of Ancient Tie-Rods

    Directory of Open Access Journals (Sweden)

    L. Collini

    2017-01-01

    Full Text Available This paper presents an application of vibration analysis to the monitoring of tie-rods. An algorithm for the axial load estimation based on experimentally measured natural frequencies is introduced and its application to a case study is reported. The proposed model of a tie-rod incorporates elastic bed-type boundary conditions that represent the contact between stonework and the tie-rod. The weighed differences between experimentally and numerically determined frequencies are minimized with respect to the parameters of the model, the main being the axial load and the stiffness at the tie-rod/wall interface. Thus, the multidimensional optimization problem is solved. Results are analysed in comparison to a model with simple fixed-end boundary conditions. In addition, the analytical formulation of the problem is delivered.

  10. Family ties and depression across the life course: An Overview

    Directory of Open Access Journals (Sweden)

    Nienke Moor

    2012-08-01

    Full Text Available BACKGROUND Family ties in Europe are affected by demographic trends associated with parenting and partnering, such as a decline in fertility, an increase in childlessness, postponement of parenthood and of partnership formation, the rise of "new" relationship forms and divorce rates. It is unclear how the contemporary family structure and composition are associated with people's mental wellbeing. OBJECTIVE This article examines how ties with parents, siblings, a partner and children are associated with depressive mood of men and women in seven Eastern and Western European countries. METHODS To test our hypotheses we made use of data from the Generations and Gender Surveys. We performed logistic regression analyses to study the associations between people's family ties and depressive mood. RESULTS Our research findings show that family ties can diminish people's depressive feelings. Although we find some gender differences in these associations, we do not find support for the argument that family ties are more important for the mental wellbeing of women than of men. Moreover, our findings support the hierarchical model of family relations in which new ties with partner and children in adulthood gain precedence over the original primary ties with parents and siblings. Finally, we find that the association between family ties and depressive mood is quite similar in Eastern and Western Europe, but being married or having a partner more strongly reduces depressive feelings in Eastern than in Western Europe. CONCLUSIONS Although we did not dispose of longitudinal data, our research results do provide some indications about how demographic changes, for instance, those affecting family size -- the number of children or siblings -- might be associated with mental wellbeing. Our findings also suggest that the demographic trend of increasing partnership dissolution may have larger consequences for people's mental wellbeing in Eastern

  11. Leaving Libertarianism: : Social Ties in Robert Nozick's New Philosophy

    OpenAIRE

    Herbjørnsrud, Dag

    2002-01-01

    SUMMARY This thesis Leaving Libertarianism: Social Ties in Robert Nozick s New Philosophy challenges the general and most widespread portrayals of the American philosopher Robert Nozick (1938-2002) by studying the notion of social ties in his later philosophy. The point of departure is the present descriptions of Nozick s philosophy. Mostly these depictions are based upon three postulates: That Nozick is an extreme individualist, that the libertarian Anarchy, State, and Utopia (1...

  12. Redoable Tie-Over Dressing Using Multiple Loop Silk Threads

    Directory of Open Access Journals (Sweden)

    Hyeon Jong Jo

    2013-05-01

    Full Text Available After skin grafting, to prevent hematoma or seroma collection at the graft site, a tie-over dressing has been commonly used. However, although the conventional tie-over dressing by suture is a useful method for securing a graft site, refixation is difficult when repeated tieover dressing is needed. Therefore, we recommend a redoable tie-over dressing technique with multiple loops threads and connecting silk threads. After the raw surface of each of our cases was covered with a skin graft, multiple loop silk thread attached with nylon at the skin graft margin. We applied the ointment gauze and wet cotton/fluffy gauze over the skin graft, then fixed the dressing by connecting cross-counter multiple loop thread with connecting silk threads. When we opened the tie-over dressing by cutting the connecting silk threads, we repeated the tie-over dressing with the same method. The skin graft was taken successfully without hematoma or seroma collection or any other complications. In conclusion, we report a novel tie-over dressing enabling simple fixation of the dressing to maintain proper tension for wounds that require repetitive fixation. Further, with this reliable method, the skin grafts were well taken.

  13. Localization of the angiopoietin receptors Tie-1 and Tie-2 on the primary cilia in the female reproductive organs

    DEFF Research Database (Denmark)

    Teilmann, Stefan C; Christensen, Søren T

    2005-01-01

    Blood vessel homeostasis and endothelial cell survival depend on proper signalling through angiopoietin receptors such as the receptor tyrosine kinases Tie-1 and Tie-2. We have studied the presence and subcellular localization of these receptors in murine female reproductive organs using confocal...... organs play a novel and important sensory role in relaying physiochemical changes from the extracellular environment to epithelial cells of the oviduct, the ovary and extra-ovarian tissues.......Blood vessel homeostasis and endothelial cell survival depend on proper signalling through angiopoietin receptors such as the receptor tyrosine kinases Tie-1 and Tie-2. We have studied the presence and subcellular localization of these receptors in murine female reproductive organs using confocal...

  14. OPTIMIZING THE DISTRIBUTION OF TIE POINTS FOR THE BUNDLE ADJUSTMENT OF HRSC IMAGE MOSAICS

    Directory of Open Access Journals (Sweden)

    J. Bostelmann

    2017-07-01

    Full Text Available For a systematic mapping of the Martian surface, the Mars Express orbiter is equipped with a multi-line scanner: Since the beginning of 2004 the High Resolution Stereo Camera (HRSC regularly acquires long image strips. By now more than 4,000 strips covering nearly the whole planet are available. Due to the nine channels, each with different viewing direction, and partly with different optical filters, each strip provides 3D and color information and allows the generation of digital terrain models (DTMs and orthophotos. To map larger regions, neighboring HRSC strips can be combined to build DTM and orthophoto mosaics. The global mapping scheme Mars Chart 30 is used to define the extent of these mosaics. In order to avoid unreasonably large data volumes, each MC-30 tile is divided into two parts, combining about 90 strips each. To ensure a seamless fit of these strips, several radiometric and geometric corrections are applied in the photogrammetric process. A simultaneous bundle adjustment of all strips as a block is carried out to estimate their precise exterior orientation. Because size, position, resolution and image quality of the strips in these blocks are heterogeneous, also the quality and distribution of the tie points vary. In absence of ground control points, heights of a global terrain model are used as reference information, and for this task a regular distribution of these tie points is preferable. Besides, their total number should be limited because of computational reasons. In this paper, we present an algorithm, which optimizes the distribution of tie points under these constraints. A large number of tie points used as input is reduced without affecting the geometric stability of the block by preserving connections between strips. This stability is achieved by using a regular grid in object space and discarding, for each grid cell, points which are redundant for the block adjustment. The set of tie points, filtered by the

  15. 78 FR 75545 - Prestressed Concrete Steel Rail Tie Wire From the People's Republic of China: Preliminary...

    Science.gov (United States)

    2013-12-12

    ... DEPARTMENT OF COMMERCE International Trade Administration [A-570-990] Prestressed Concrete Steel... (``Department'') preliminarily determines that prestressed concrete steel rail tie wire (``PC tie wire'') from... prestressed tendons in concrete railroad ties (``PC tie wire''). High carbon steel is defined as steel that...

  16. The Spontaneous Combustion of Railway Ties and Asphalt Shingles

    Science.gov (United States)

    Leslie, Geoffrey

    Many Low Carbon Fuels (LCFs) present unknown spontaneous combustion risks, which must be quantified before their use as fossil fuel replacements. Wood and coal spontaneous combustion is well understood; however, LCFs weather, and subsequent chemical changes could affect their spontaneous combustion properties. LCF spontaneous combustion could lead to accidental fires with possible loss of life, limb and property. The spontaneous combustion risks of two LCFs, discarded creosote-treated wooden railway ties and roofing asphalt shingles, were investigated with calorimetry and heat transfer experiments. Chemical changes due to weathering were studied with pyrolysis-Gas Chromatography/Mass Spectrometry (py-GC/MS). Creosote-treated wooden railway tie dust, roofing asphalt shingle particles, poplar wood pellets, and petroleum coke self-heating were studied with isothermal calorimetry. Railway tie dust and asphalt shingle heat transfer were characterized with a guarded hot plate. Petroleum coke self-heating was consistent with coal, while both poplar pellets and railway tie dust were found to be more reactive compared to oven test results of similar materials. The observed increase in reactivity was probably a result of significant moisture contenint in the pellet and railway tie dust. Critical conditions for spontaneous combustion were evaluated with the Frank-Kamenetskii parameter, assuming an ambient temperature of 40°C and constant moisture content. Kamenetskii calculations indicate that a 1.6 m cube of railway tie dust, or a 58 m cube of asphalt particles, would be unstable and combust. LCF chemistry may have been affected by weathering, which would cause chemical changes that affect their spontaneous combustion properties. Therefore, railway tie wood and roofing asphalt shingle chemistry were investigated by identifying products of 250° and 550°C pyrolysis with py-GC/MS. Railway tie wood pyrolyzates did not show signs of weathering; in contrast, asphalt pyrolysis

  17. Robust tie points selection for InSAR image coregistration

    Science.gov (United States)

    Skanderi, Takieddine; Chabira, Boulerbah; Afifa, Belkacem; Belhadj Aissa, Aichouche

    2013-10-01

    Image coregistration is an important step in SAR interferometry which is a well known method for DEM generation and surface displacement monitoring. A practical and widely used automatic coregistration algorithm is based on selecting a number of tie points in the master image and looking for the correspondence of each point in the slave image using correlation technique. The characteristics of these points, their number and their distribution have a great impact on the reliability of the estimated transformation. In this work, we present a method for automatic selection of suitable tie points that are well distributed over the common area without decreasing the desired tie points' number. First we select candidate points using Harris operator. Then from these points we select tie points depending on their cornerness measure (the highest first). Once a tie point is selected, its correspondence is searched for in the slave image, if the similarity measure maximum is less than a given threshold or it is at the border of the search window, this point is discarded and we proceed to the next Harris point, else, the cornerness of the remaining candidates Harris points are multiplied by a spatially radially increasing function centered at the selected point to disadvantage the points in a neighborhood of a radius determined from the size of the common area and the desired number of points. This is repeated until the desired number of points is selected. Results of an ERS1/2 tandem pair are presented and discussed.

  18. Social ties and risk for cancer - a prospective cohort study

    DEFF Research Database (Denmark)

    Bergelt, Corinna; Prescott, Eva; Grønbaek, Morten

    2009-01-01

    consisted of 8 548 Danes who had been examined in 1991-1994 within the Copenhagen City Heart Study. The median length of follow-up was 9.3 years (range, 0-11.2 years). Social ties were measured from answers to a questionnaire on social networks. Regression analyses for cancers at the most frequent sites......BACKGROUND: Poor social support and small social networks have been associated with increased risks for conditions such as coronary heart disease as well as with overall mortality. We investigated the association between social ties and risk for cancer. MATERIAL AND METHODS: The study sample...... (breast, lung, prostate and colon and rectum) were conducted with the Cox proportional hazards model, with adjustment for a number of well-known risk factors for cancer. RESULTS: While we found no significant association between social ties and risk for cancer in men, women with high social network scores...

  19. Social ties and risk for cancer - a prospective cohort study

    DEFF Research Database (Denmark)

    Bergelt, C.; Prescott, E.; Gronbaek, M.

    2009-01-01

    consisted of 8 548 Danes who had been examined in 1991-1994 within the Copenhagen City Heart Study. The median length of follow-up was 9.3 years (range, 0-11.2 years). Social ties were measured from answers to a questionnaire on social networks. Regression analyses for cancers at the most frequent sites......Background. Poor social support and small social networks have been associated with increased risks for conditions such as coronary heart disease as well as with overall mortality. We investigated the association between social ties and risk for cancer. Material and methods. The study sample...... (breast, lung, prostate and colon and rectum) were conducted with the Cox proportional hazards model, with adjustment for a number of well-known risk factors for cancer. Results. While we found no significant association between social ties and risk for cancer in men, women with high social network scores...

  20. Stability and failure analysis of steering tie-rod

    Science.gov (United States)

    Jiang, GongFeng; Zhang, YiLiang; Xu, XueDong; Ding, DaWei

    2008-11-01

    A new car in operation of only 8,000 km, because of malfunction, resulting in lost control and rammed into the edge of the road, and then the basic vehicle scrapped. According to the investigation of the site, it was found that the tie-rod of the car had been broken. For the subjective analysis of the accident and identifying the true causes of rupture of the tierod, a series of studies, from the angle of theory to experiment on the bended broken tie-rod, were conducted. The mechanical model was established; the stability of the defective tie-rod was simulated based on ANSYS software. Meanwhile, the process of the accident was simulated considering the effect of destabilization of different vehicle speed and direction of the impact. Simultaneously, macro graphic test, chemical composition analysis, microstructure analysis and SEM analysis of the fracture were implemented. The results showed that: 1) the toughness of the tie-rod is at a normal level, but there is some previous flaws. One quarter of the fracture surface has been cracked before the accident. However, there is no relationship between the flaw and this incident. The direct cause is the dynamic instability leading to the large deformation of impact loading. 2) The declining safety factor of the tie-rod greatly due to the previous flaws; the result of numerical simulation shows that previous flaw is the vital factor of structure instability, on the basis of the comparison of critical loads of the accident tie-rod and normal. The critical load can decrease by 51.3% when the initial defect increases 19.54% on the cross-sectional area, which meets the Theory of Koiter.

  1. Endothelial Activation: The Ang/Tie Axis in Sepsis

    Directory of Open Access Journals (Sweden)

    Aleksandra Leligdowicz

    2018-04-01

    Full Text Available Sepsis, a dysregulated host response to infection that causes life-threatening organ dysfunction, is a highly heterogeneous syndrome with no specific treatment. Although sepsis can be caused by a wide variety of pathogenic organisms, endothelial dysfunction leading to vascular leak is a common mechanism of injury that contributes to the morbidity and mortality associated with the syndrome. Perturbations to the angiopoietin (Ang/Tie2 axis cause endothelial cell activation and contribute to the pathogenesis of sepsis. In this review, we summarize how the Ang/Tie2 pathway is implicated in sepsis and describe its prognostic as well as therapeutic utility in life-threatening infections.

  2. TIE-2 and VEGFR kinase activities drive immunosuppressive function of TIE-2-expressing monocytes in human breast tumors.

    Science.gov (United States)

    Ibberson, Mark; Bron, Sylvian; Guex, Nicolas; Faes-van't Hull, Eveline; Ifticene-Treboux, Assia; Henry, Luc; Lehr, Hans-Anton; Delaloye, Jean-François; Coukos, George; Xenarios, Ioannis; Doucey, Marie-Agnès

    2013-07-01

    Tumor-associated TIE-2-expressing monocytes (TEM) are highly proangiogenic cells critical for tumor vascularization. We previously showed that, in human breast cancer, TIE-2 and VEGFR pathways control proangiogenic activity of TEMs. Here, we examine the contribution of these pathways to immunosuppressive activity of TEMs. We investigated the changes in immunosuppressive activity of TEMs and gene expression in response to specific kinase inhibitors of TIE-2 and VEGFR. The ability of tumor TEMs to suppress tumor-specific T-cell response mediated by tumor dendritic cells (DC) was measured in vitro. Characterization of TEM and DC phenotype in addition to their interaction with T cells was done using confocal microscopic images analysis of breast carcinomas. TEMs from breast tumors are able to suppress tumor-specific immune responses. Importantly, proangiogenic and suppressive functions of TEMs are similarly driven by TIE-2 and VEGFR kinase activity. Furthermore, we show that tumor TEMs can function as antigen-presenting cells and elicit a weak proliferation of T cells. Blocking TIE-2 and VEGFR kinase activity induced TEMs to change their phenotype into cells with features of myeloid dendritic cells. We show that immunosuppressive activity of TEMs is associated with high CD86 surface expression and extensive engagement of T regulatory cells in breast tumors. TIE-2 and VEGFR kinase activity was also necessary to maintain high CD86 surface expression levels and to convert T cells into regulatory cells. These results suggest that TEMs are plastic cells that can be reverted from suppressive, proangiogenic cells into cells that are able to mediate an antitumoral immune response. ©2013 AACR.

  3. TIE - DYE (ADIRE) AMONG THE JUKUN PEOPLE Gausa Solomon ...

    African Journals Online (AJOL)

    SO

    clothing scraps or fibrous materials from municipal waste stream (Wikipedia, 2014). ... example fabric that has been tie-dyed can be recycled and used as lamp shades, .... Dye colour is used in the manufacture of plastic products, but their most ...

  4. The Ties That Bind Exhibition Science Bringing Nations Together

    CERN Document Server

    1997-01-01

    Scientific ties between JINR and CERN date back to 1957, when JINR Vice-Director Marian Danysz, a Polish professor, visited CERN and agreed with CERN Director-General C.J. Bakker on the exchange of scientists and on joint experiments. Since that time to progress and now JINR takes an active part in the Large Hadron Collider, LHC, project at CERN.

  5. Affective social ties - missing link in governance theory

    NARCIS (Netherlands)

    van Winden, F.A.A.M.

    2012-01-01

    Although governance is about interpersonal relationships, it appears that the antecedents and consequences of affective bonds (social ties) in social groups dealing with common-pool resources and public goods have been neglected. The welfare costs of the neglect of such bonds and their dynamic

  6. Matrilineal Family Ties and Marital Dissolution in Ghana

    Science.gov (United States)

    Takyi, Baffour K.; Gyimah, Stephen Obeng

    2007-01-01

    Although previous work has attributed the instability of African marriages to the diffusion of Western norms and values in the region, fewer attempts have been made to empirically assess how Africa's internal institutional structures, such as extended kinship ties, impact marital outcomes. Guided by rational choice and exchange theories, we argue…

  7. Knotcraft the practical and entertaining art of tying knots

    CERN Document Server

    Macfarlan, Allan and Paulette

    1983-01-01

    Comprehensive reference work explains how to tie hundreds of practical (and decorative) knots in clear illustrations and precisely worded written instructions. Ideal for boaters and campers. Also covers knots in history, knot mystery and magic, and games, stunts and tricks with rope. Introduction. Index. 166 black-and-white illustrations.

  8. Application of Bow-tie methodology to improve patient safety.

    Science.gov (United States)

    Abdi, Zhaleh; Ravaghi, Hamid; Abbasi, Mohsen; Delgoshaei, Bahram; Esfandiari, Somayeh

    2016-05-09

    Purpose - The purpose of this paper is to apply Bow-tie methodology, a proactive risk assessment technique based on systemic approach, for prospective analysis of the risks threatening patient safety in intensive care unit (ICU). Design/methodology/approach - Bow-tie methodology was used to manage clinical risks threatening patient safety by a multidisciplinary team in the ICU. The Bow-tie analysis was conducted on incidents related to high-alert medications, ventilator associated pneumonia, catheter-related blood stream infection, urinary tract infection, and unwanted extubation. Findings - In total, 48 potential adverse events were analysed. The causal factors were identified and classified into relevant categories. The number and effectiveness of existing preventive and protective barriers were examined for each potential adverse event. The adverse events were evaluated according to the risk criteria and a set of interventions were proposed with the aim of improving the existing barriers or implementing new barriers. A number of recommendations were implemented in the ICU, while considering their feasibility. Originality/value - The application of Bow-tie methodology led to practical recommendations to eliminate or control the hazards identified. It also contributed to better understanding of hazard prevention and protection required for safe operations in clinical settings.

  9. Competition increases in the face of strong regional ties

    International Nuclear Information System (INIS)

    Knoetgen, P.M.

    1987-01-01

    The current fuel market exhibits a large surplus production capacity and is strongly influenced by regional ties, with imports of fabricated fuel serving to supplement domestic production or to keep domestic vendors competitive. In the future, the market is set to become increasingly competitive, especially in Europe and the United States. (author)

  10. Neural correlates of dynamically evolving interpersonal ties predict prosocial behaviour

    Directory of Open Access Journals (Sweden)

    Johannes Jacobus Fahrenfort

    2012-03-01

    Full Text Available There is a growing interest for the determinants of human choice behaviour in social settings. Upon initial contact, investment choices in social settings can be inherently risky, as the degree to which the other person will reciprocate is unknown. Nevertheless, people have been shown to exhibit prosocial behaviour even in one-shot laboratory settings where all interaction has been taken away. A logical step has been to link such behaviour to trait empathy-related neurobiological networks. However, as a social interaction unfolds, the degree of uncertainty with respect to the expected payoff of choice behaviour may change as a function of the interaction. Here we attempt to capture this factor. We show that the interpersonal tie one develops with another person during interaction - rather than trait empathy - motivates investment in a public good that is shared with an anonymous interaction partner. We examined how individual differences in trait empathy and interpersonal ties modulate neural responses to imposed monetary sharing. After, but not before interaction in a public good game, sharing prompted activation of neural systems associated with reward (striatum, empathy (anterior insular cortex [AIC] and anterior cingulate cortex [ACC] as well as altruism and social significance (posterior superior temporal sulcus [pSTS]. Although these activations could be linked to both empathy and interpersonal ties, only tie-related pSTS activation predicted prosocial behaviour during subsequent interaction, suggesting a neural substrate for keeping track of social relevance.

  11. The Strength of the Strongest Ties in Collaborative Problem Solving

    Science.gov (United States)

    de Montjoye, Yves-Alexandre; Stopczynski, Arkadiusz; Shmueli, Erez; Pentland, Alex; Lehmann, Sune

    2014-06-01

    Complex problem solving in science, engineering, and business has become a highly collaborative endeavor. Teams of scientists or engineers collaborate on projects using their social networks to gather new ideas and feedback. Here we bridge the literature on team performance and information networks by studying teams' problem solving abilities as a function of both their within-team networks and their members' extended networks. We show that, while an assigned team's performance is strongly correlated with its networks of expressive and instrumental ties, only the strongest ties in both networks have an effect on performance. Both networks of strong ties explain more of the variance than other factors, such as measured or self-evaluated technical competencies, or the personalities of the team members. In fact, the inclusion of the network of strong ties renders these factors non-significant in the statistical analysis. Our results have consequences for the organization of teams of scientists, engineers, and other knowledge workers tackling today's most complex problems.

  12. Children's Books in Review: Books on Strengthening Family Ties.

    Science.gov (United States)

    Winfield, Evelyn T.

    1991-01-01

    Reviews children's books that emphasize the strengthening of family ties. Characters in the books realize the importance and influence of family relationships as they struggle with sibling rivalry, self-discovery, peer relationships, a search for heritage, adoption, and death. (SM)

  13. Measurement of the location of tie-bar shoulders

    CERN Multimedia

    Hubert Gerwig

    2001-01-01

    The inner vactank is machined on a length of 13m at the location of the rails for HCAL. in addition at one side the inner vactank has shoulders to lodge the M48 tie-bars that will guarantee the fixation to the swivelling platform actually produced at HANJUNG Company in South Korea

  14. Maintaining work-related personal ties following retirement

    NARCIS (Netherlands)

    Cozijnsen, M.R.; Stevens, N.L.; van Tilburg, T.G.

    2010-01-01

    This study examines the consequences of retirement for the continuation of work-related personal ties. The hypothesis is that their inclusion in personal networks after retirement has become more likely because these relationships have become less role based in today's social-cultural context. Data

  15. Urban violence and displacement, gender, and community ties ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2017-10-20

    Oct 20, 2017 ... SAIC experts explored poverty, violence, and inequality in 40 cities across Latin America, South Asia, and sub-Saharan Africa. The 15 research ... Urban violence and displacement, gender, and community ties. October 20 ... in urban spaces. Return to main page: Solutions to make cities safe and inclusive.

  16. Preventing Cauliflower Ear with a Modified Tie-Through Technique.

    Science.gov (United States)

    Dimeff, Robert J.; Hough, David O.

    1989-01-01

    Describes a quick, simple tie-through suture technique (in which a collodion packing is secured to the auricle with two buttons) for preventing cauliflower ear following external ear trauma in wrestlers and boxers. The technique ensures constant compression; multiple treatments for fluid reaccumulation are rarely necessary. (SM)

  17. Ion channeling

    International Nuclear Information System (INIS)

    Erramli, H.; Blondiaux, G.

    1994-01-01

    Channeling phenomenon was predicted, many years ago, by stark. The first channeling experiments were performed in 1963 by Davies and his coworkers. Parallely Robinson and Oen have investigated this process by simulating trajectories of ions in monocrystals. This technique has been combined with many methods like Rutherford Backscattering Spectrometry (R.B.S.), Particles Induced X-rays Emission (P.I.X.E) and online Nuclear Reaction (N.R.A.) to localize trace elements in the crystal or to determine crystalline quality. To use channeling for material characterization we need data about the stopping power of the incident particle in the channeled direction. The ratios of channeled to random stopping powers of silicon for irradiation in the direction have been investigated and compared to the available theoretical results. We describe few applications of ion channeling in the field of materials characterization. Special attention is given to ion channeling combined with Charged Particle Activation Analysis (C.P.A.A.) for studying the behaviour of oxygen atoms in Czochralski silicon lattices under the influence of internal gettering and in different gaseous atmospheres. Association between ion channeling and C.P.A.A was also utilised for studying the influence of the growing conditions on concentration and position of carbon atoms at trace levels in the MOVPE Ga sub (1-x) Al sub x lattice. 6 figs., 1 tab., 32 refs. (author)

  18. High tie versus low tie of the inferior mesenteric artery in colorectal cancer: A meta-analysis.

    Science.gov (United States)

    Yang, Yafan; Wang, Guiying; He, Jingli; Zhang, Jianfeng; Xi, Jinchuan; Wang, Feifei

    2018-04-01

    Colorectal cancer surgery includes "high tie" and "low tie"of the inferior mesenteric artery(IMA). However, different ligation level is closely related to the blood supply of anastomosis, which may increase the leakage rate, and it is unclear which technique confers a lower anastomotic leakage rate(AL) and survival advantage. To compare the effectiveness and impact of inferior mesenteric artery (IMA) high ligation versus IMA low ligation on anastomotic leakage, lymph nodes yield rates and 5-year survival. A list of these studies, published in English from 1990 to 2017, was obtained independently by two reviewers from databases such as PubMed, Medline, ScienceDirect and Web of Science. Anastomotic leakage rate, the yield of lymph nodes and 5-year survival were compared using Review Manager 5.3. There was no significant difference in anastomotic leakage, number of lymph nodes retrieved and 5-year survival rate for both techniques. Neither the high tie nor the low tie strategy has an evidence in terms of anastomotic leakage rate, harvested lymph nodes, and the 5-year survival rate. Further RCT is needed. Copyright © 2018 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.

  19. Channel box

    International Nuclear Information System (INIS)

    Tanabe, Akira.

    1993-01-01

    In a channel box of a BWR type reactor, protruding pads are disposed in axial position on the lateral side of a channel box opposing to a control rod and facing the outer side portion of the control rod in a reactor core loaded state. In the initial loading stage of fuel assemblies, channel fasteners and spacer pads are abutted against each other in the upper portion between the channel boxes sandwiching the control rod therebetween. Further, in the lower portion, a gap as a channel for the movement of the control rod is ensured by the support of fuel support metals. If the channel box is bent toward the control rod along with reactor operation, the pads are abutted against each other to always ensure the gap through which the control rod can move easily. Further, when the pads are brought into contact with each other, the bending deformation of the channel box is corrected by urging to each other. Thus, the control rod can always be moved smoothly to attain reactor safety operation. (N.H.)

  20. Four- year thyroidectomy procedures: Ligasure Vs. clamp & tie

    Directory of Open Access Journals (Sweden)

    Pazoki AR

    2010-01-01

    Full Text Available "n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: The electrothermal bipolar vessel sealing system is an adjunct to the hemostatic technique, which has been successfully used in many abdominal operation, recently made available to thyroid surgery. The purpose of this was compare the outcomes of new hemostatic technique with traditional method of clamp and tie."n"nMethods: In this retrospective cross-sectional study has been done in surgery's wards of Milad & Rasul- Akram hospitals in Tehran, Iran. During three- year period between 2005-2008 all patients with different kind of pathology that need operation were assessed. Time duration of surgery and hospital stay and post surgery complication in two group, ligasure (n=45 and clamp & tie (n=145 were compared with each others."n"nResults: No difference was seen between two groups in time duration of surgery. Significant difference was seen in hospital stay and complications of surgery. Time of operation in Ligasure group was 132/22 minute and in clamp and tie group was 130/10 minute. There was found significant difference in duration of hospital stay and postoperative complication. Hypocalcemia were seen in two and 24 cases in Ligasure and Clamp & Tie group, respectively (p<0.05. Hospital stay was 2

  1. Linkage of genomic biomarkers to whole organism endpoints in a Toxicity Identification Evaluation (TIE).

    Science.gov (United States)

    Aquatic organisms are exposed to many toxic chemicals and interpreting the cause and effect relationships between occurrence and impairment is difficult. Toxicity Identification Evaluation (TIE) provides a systematic approach for identifying responsible toxicants. TIE relies on ...

  2. Surface channeling

    International Nuclear Information System (INIS)

    Sizmann, R.; Varelas, C.

    1976-01-01

    There is experimental evidence that swift light ions incident at small angles towards single crystalline surfaces can lose an appreciable fraction of their kinetic energy during reflection. It is shown that these projectiles penetrate into the bulk surface region of the crystal. They can travel as channeled particles along long paths through the solid (surface channeling). The angular distribution and the depth history of the re-emerged projectiles are investigated by computer simulations. A considerable fraction of the penetrating projectiles re-emerges from the crystal with constant transverse energy if the angle of incidence is smaller than the critical angle for axial channeling. Analytical formulae are derived based on a diffusion model for surface channeling. A comparison with experimental data exhibits the relevance of the analytical solutions. (Auth.)

  3. Modelling the flooding capacity of a Polish Carpathian river: A comparison of constrained and free channel conditions

    Science.gov (United States)

    Czech, Wiktoria; Radecki-Pawlik, Artur; Wyżga, Bartłomiej; Hajdukiewicz, Hanna

    2016-11-01

    The gravel-bed Biała River, Polish Carpathians, was heavily affected by channelization and channel incision in the twentieth century. Not only were these impacts detrimental to the ecological state of the river, but they also adversely modified the conditions of floodwater retention and flood wave passage. Therefore, a few years ago an erodible corridor was delimited in two sections of the Biała to enable restoration of the river. In these sections, short, channelized reaches located in the vicinity of bridges alternate with longer, unmanaged channel reaches, which either avoided channelization or in which the channel has widened after the channelization scheme ceased to be maintained. Effects of these alternating channel morphologies on the conditions for flood flows were investigated in a study of 10 pairs of neighbouring river cross sections with constrained and freely developed morphology. Discharges of particular recurrence intervals were determined for each cross section using an empirical formula. The morphology of the cross sections together with data about channel slope and roughness of particular parts of the cross sections were used as input data to the hydraulic modelling performed with the one-dimensional steady-flow HEC-RAS software. The results indicated that freely developed cross sections, usually with multithread morphology, are typified by significantly lower water depth but larger width and cross-sectional flow area at particular discharges than single-thread, channelized cross sections. They also exhibit significantly lower average flow velocity, unit stream power, and bed shear stress. The pattern of differences in the hydraulic parameters of flood flows apparent between the two types of river cross sections varies with the discharges of different frequency, and the contrasts in hydraulic parameters between unmanaged and channelized cross sections are most pronounced at low-frequency, high-magnitude floods. However, because of the deep

  4. Mobile phones, social ties, and collective action mobilization in China

    DEFF Research Database (Denmark)

    Liu, Jun

    2017-01-01

    To provide a better understanding of mobile phones as a recruitment tool in collective actions, this study explores the use of mobile phones for mobilizing protest in China. Using in-depth interviews and investigating four cases in which Chinese people employed mobile devices to recruit...... participants for protests, this study observes that mobile communication in China embodies guanxi, the indigenous social tie in Chinese society that introduces reciprocity as an influential facilitator of collective actions. The embedment of reciprocity facilitates the proliferation of mobilizing calls......, legitimizes mobilizing appeals, generates obligations and consolidates solidarity for collective actions. The study concludes with a consideration of the relevance of mobile phones for the embedment of reciprocity in social ties in the mobilization of collective action in authoritarian regimes such as China....

  5. Personal Ties in the Writing of a Doctoral Dissertation

    Directory of Open Access Journals (Sweden)

    Laura Colombo

    2014-07-01

    Full Text Available The problem of low graduation rates at the graduate level has been linked to the challenges of dissertation work. Given that this is a process of “disciplinary enculturation”, where graduate students acquire the ways of being and doing of each discipline, the social relations of doctoral candidates should be analyzed. Several studies have explored the support provided by social ties within academia but have, nevertheless, ignored other spheres. This qualitative study, based on in-depth interviews, explores the personal-sphere social relations in the dissertation writing process from the point of view of doctoral candidates and recent graduates in the fields of Education and Linguistics. Results indicate that the emotional, financial, economic, and academic support offered by these social ties is a necessary, although not in itself, sufficient condition. Some strategies for increasing institutional support to facilitate the process of writing a dissertation are offered.

  6. Spark Channels

    Energy Technology Data Exchange (ETDEWEB)

    Haydon, S. C. [Department of Physics, University of New England, Armidale, NSW (Australia)

    1968-04-15

    A brief summary is given of the principal methods used for initiating spark channels and the various highly time-resolved techniques developed recently for studies with nanosecond resolution. The importance of the percentage overvoltage in determining the early history and subsequent development of the various phases of the growth of the spark channel is discussed. An account is then given of the recent photographic, oscillographic and spectroscopic investigations of spark channels initiated by co-axial cable discharges of spark gaps at low [{approx} 1%] overvoltages. The phenomena observed in the development of the immediate post-breakdown phase, the diffuse glow structure, the growth of the luminous filament and the final formation of the spark channel in hydrogen are described. A brief account is also given of the salient features emerging from corresponding studies of highly overvolted spark gaps in which the spark channel develops from single avalanche conditions. The essential differences between the two types of channel formation are summarized and possible explanations of the general features are indicated. (author)

  7. Physical Drivers Vs. Effects of the Wolf-Elk Trophic Cascade on Fluvial Channel Planform, Olympic National Park, Washington

    Science.gov (United States)

    East, A. E.; Jenkins, K. J.; Happe, P. J.; Bountry, J.; Beechie, T. J.; Mastin, M. C.; Sankey, J. B.; Randle, T. J.

    2016-12-01

    Identifying the relative contributions of physical and ecological processes to channel evolution remains a substantial challenge in fluvial geomorphology. We use a 74-year aerial photographic record of the Hoh, Queets, Quinault, and Elwha Rivers, Olympic National Park, Washington, U.S.A., to investigate whether physical or trophic-cascade-driven ecological factors—excessive elk impacts after wolves were extirpated a century ago—are the dominant controls on channel planform of these gravel-bed rivers. We find that channel width and braiding show strong relationships with recent flood history; all four rivers have widened significantly in recent decades, consistent with increased flood activity since the 1970s. Channel planform also reflects sediment-supply changes, shown, for example, by the response of the Elwha River to a landslide. We surmise that the Hoh River, which shows a multi-decadal trend toward greater braiding, is adjusting to increased sediment supply associated with rapid glacial retreat. These rivers demonstrate rapid transmission of climatic signals through relatively short sediment-routing systems that lack substantial buffering by sediment storage. We infer no correspondence between channel evolution and elk abundance, suggesting that in this system effects of the wolf-driven trophic cascade are subsidiary to physical controls on channel morphology. Our examinations of stage-discharge history, historical maps, photographs, and descriptions, and empirical geomorphic thresholds do not support a previous conceptual model that these rivers underwent a fundamental geomorphic transition (widening, and a shift from single-thread to braided) resulting from large elk populations in the early 20th century. These findings differ from previous interpretations of Olympic National Park river dynamics, and also contrast with previous findings in Yellowstone National Park, where legacy effects of abundant elk nearly a century ago apparently still affect

  8. The Ties That Bind Exhibition Science Bringing Nations Together

    CERN Document Server

    2000-01-01

    Scientific ties between JINR and CERN date back to 1957, when JINR Vice-Director Marian Danysz, a Polish professor, visited CERN and agreed with CERN Director-General C.J. Bakker on the exchange of scientists and on joint experiments. Political confrontation did not affect extensive contacts between scientists. By the early 1970s, the meetings of the heads of two international centres, JINR and CERN, had become regular occurrences.

  9. The ties between natural gas and oil prices

    International Nuclear Information System (INIS)

    Maisonnier, G.

    2006-01-01

    On the European continent, the price of natural gas is still tied directly and to a great extent to the price of competing energies, especially heavy fuel oil and home heating oil. In other words, the gas market is linked to the oil market. Under the effect of deregulation, this model is likely to change in the future, making a shift like that which took place on the American market in the past. (author)

  10. It's the recipient that counts: spending money on strong social ties leads to greater happiness than spending on weak social ties.

    Directory of Open Access Journals (Sweden)

    Lara B Aknin

    Full Text Available Previous research has shown that spending money on others (prosocial spending increases happiness. But, do the happiness gains depend on who the money is spent on? Sociologists have distinguished between strong ties with close friends and family and weak ties--relationships characterized by less frequent contact, lower emotional intensity, and limited intimacy. We randomly assigned participants to reflect on a time when they spent money on either a strong social tie or a weak social tie. Participants reported higher levels of positive affect after recalling a time they spent on a strong tie versus a weak tie. The level of intimacy in the relationship was more important than the type of relationship; there was no significant difference in positive affect after recalling spending money on a family member instead of a friend. These results add to the growing literature examining the factors that moderate the link between prosocial behaviour and happiness.

  11. It's the recipient that counts: spending money on strong social ties leads to greater happiness than spending on weak social ties.

    Science.gov (United States)

    Aknin, Lara B; Sandstrom, Gillian M; Dunn, Elizabeth W; Norton, Michael I

    2011-02-10

    Previous research has shown that spending money on others (prosocial spending) increases happiness. But, do the happiness gains depend on who the money is spent on? Sociologists have distinguished between strong ties with close friends and family and weak ties--relationships characterized by less frequent contact, lower emotional intensity, and limited intimacy. We randomly assigned participants to reflect on a time when they spent money on either a strong social tie or a weak social tie. Participants reported higher levels of positive affect after recalling a time they spent on a strong tie versus a weak tie. The level of intimacy in the relationship was more important than the type of relationship; there was no significant difference in positive affect after recalling spending money on a family member instead of a friend. These results add to the growing literature examining the factors that moderate the link between prosocial behaviour and happiness.

  12. Automated Simultaneous Local Ties with GNSS and Robot Tacheometer

    Science.gov (United States)

    Kallio, Ulla; Lösler, Michael; Bergstrand, Sten; Haas, Rüdiger; Eschelbach, Cornelia

    2016-12-01

    We have used GPS-based local-tie measurements simultaneously with geo-VLBI observations since 2008 during every geodetic VLBI session at Metsähovi. This system uses gimbal-mounted GNSS antennas that are mounted on the reflector of the Metsähovi 14-m radio telescope. A similar system was installed in 2013 at the Onsala 20-m radio telescope and has been used for a large number of VLBI sessions, including, e.g., the 15-day-long CONT14 campaign. In order to verify the results of the two systems, we performed a dedicated measurement campaign in the framework of the SIB60 project, involving both Metsähovi and Onsala. During this campaign the local ties at the two stations were measured simultaneously during two VLBI sessions in August and September 2015 where both stations participated. The robot tacheometer monitoring system HEIMDALL was used for the automated classical monitoring of the telescopes at both stations. Moreover, additional local terrestrial measurements were performed several times to derive the full IVS-IGS local ties at both sites. The kinematic GPS measurements at the two stations were analyzed with two independently developed analysis programs. We present here the preparations of the campaign, the measurement process, and preliminary results.

  13. The emergence of cooperation in tie strength models

    International Nuclear Information System (INIS)

    Xu, Bo; Yue, Yunpeng

    2016-01-01

    In this paper, we propose a tie strength model to explain the emergence of cooperation in spatial prisoner's dilemma games, assuming that cooperators preferentially allocate their investments to friends with strong ties. Two types of prisoner's dilemma models are examined in this study: the traditional two-strategy model considering only cooperators and defectors; the expanded three-strategy model consisting cooperators, defectors and extortioners. The results show that tie strength model contributes to the promotion of cooperation in both types of prisoner's dilemma games. However, we point out that the influence of the investment preference is quite different in the two prisoner's dilemma game settings. In the two-strategy prisoner's dilemma game, only small preference contributes to the promotion of cooperation. Once this preference exceeds a critical value, cooperation will be prohibited. We explain this phenomenon by arguing that extremely strong investment preference undermines the ability of cooperative clusters to resist defectors. Moreover, we extend the analysis into the three-strategy case and discover that the catalytic effect of extortioners can eliminate this first up and then down trend in the two-strategy model. The equilibrium fraction of cooperators is always positively correlated to the level of investment preference in three-strategy models.

  14. Student Mobility and Transnational Social Ties as Factors of Reflexivity

    Directory of Open Access Journals (Sweden)

    Tea Golob

    2018-03-01

    Full Text Available The article seeks to develop and apply new quantitative measurement instruments capable of significantly improving understanding of the relationship between the transnational mobility and transnational social ties of students, along with their reflexive capacities. With a focus on students building their personal networks, educational and professional activities that extend beyond the nation’s borders and organising their day-to-day routines in transnational social spaces, we analyse the role of mobility in their reflexive capacities. Applying a tool that is line with Archer’s theory and indicators to measure reflexivity, and transnational social ties as proposed by Molina et al., we analyse data collected via an on-line survey questionnaire administered to Slovenian students. In addition, students from the Middle East (Lebanon and the USA (Hawai’i are added for comparative purposes. The results of path analysis show the Slovenian students’ mobility as such implies higher scores for meta reflexivity, combined with lower scores for communicative and fractured reflexivity. Further, social transactions reaching beyond one’s physical localities in terms of transnational social ties implies they have higher levels of reflexivity in general.

  15. ERT and Well Data Tie for Nickel Laterite Characterization

    Science.gov (United States)

    Aswad, Sabrianto; Mamela Mais, Difar; Syamsuddin; Wanni

    2018-03-01

    The need of ERT method in nickel latentes exploration can’t be deny. This method have capability to make exploration more effective and efficient. In reality this method still remain ambiguity in its application, especially for geologist and mining expert. These ambiguity related with layer zone determination (limonite, saprolite and bedrock), the same resistivity values in the different zones and determination of bedrock. This paper try to expose interesting fact to overcome this ambiguity by using ERT data and drill data tie. This tie will show characteristic of nickel lateric based on resisitivity value and the contribution of chemistry element for resistivity value. Data ERT was collected by using gradient configuration and well data consist of mayor element and minor element. Tie result showed difference resistivity value in limonite layer influence by Fe, H2O and Ni, where resistivity value from saprolite layer influenced by Fe, H2O, Si02, MgO, Al, Cr, and Ni in certain accumulation. In bedrock layer, almost all drill data did not reach bedrock but only reached the boulder alone, it is supported by the value of the resistivity of rock unserpentinized peridotite which should show a relatively large resistivity value

  16. 77 FR 21620 - Notice of the Buy America Waiver Request for Vossloh 101-LV Concrete Ties

    Science.gov (United States)

    2012-04-10

    ... the Buy America Waiver Request for Vossloh 101-LV Concrete Ties AGENCY: Federal Railroad... concrete ties, which contain certain components not manufactured in the United States. In furtherance of... concrete ties. FRA has received this request from the four States for the following projects: (a) The...

  17. Ties that Blind: Perpetuation of Racial Comfort and Discomfort at a Community College

    Science.gov (United States)

    Price, Douglas B.; Hyle, Adrienne E.; Jordan, Kitty V.

    2009-01-01

    Interviews with 17 African American students and 19 White students were employed to examine interracial relations at a predominantly White community college campus. Seen through the lens of Granovetter's strength of ties theory, the interview findings revealed that strong intraracial ties and the absence of weak interracial ties inhibited…

  18. Identifying Weak Ties from Publicly Available Social Media Data in an Event

    DEFF Research Database (Denmark)

    Prakash Gupta, Jayesh; Menon, Karan; Kärkkäinen, Hannu

    2016-01-01

    The concept of weak ties was introduced by Granovetter through the seminal paper titled "Strength of weak ties". Since then the role of weak ties in general and their specific role as occupying the structural hole has been explored in many different fields. In this study, we identify actual or po...

  19. TIES for Dummies 3rd Edition (Technology Identification, Evaluation, and Selection) Basic how to's to implement the TIES method

    Science.gov (United States)

    Kirby, Michelle R.

    2002-01-01

    The TIES method is a forecasting environment whereby the decision-maker has the ability to easily assess and trade-off the impact of various technologies without sophisticated and time-consuming mathematical formulations. TIES provides a methodical approach where technically feasible alternatives can be identified with accuracy and speed to reduce design cycle time, and subsequently, life cycle costs, and was achieved through the use of various probabilistic methods, such as Response Surface Methodology and Monte Carlo Simulations. Furthermore, structured and systematic techniques are utilized from other fields to identify possible concepts and evaluation criteria by which comparisons can be made. This objective is achieved by employing the use of Morphological Matrices and Multi-Attribute Decision Making techniques. Through the execution of each step, a family of design alternatives for a given set of customer requirements can be identified and assessed subjectively or objectively. This methodology allows for more information (knowledge) to be brought into the earlier phases of the design process and will have direct implications on the affordability of the system. The increased knowledge allows for optimum allocation of company resources and quantitative justification for program decisions. Finally, the TIES method provided novel results and quantitative justification to facilitate decision making in the early stages of design so as to produce affordable and quality products.

  20. MARKETING CHANNELS

    Directory of Open Access Journals (Sweden)

    Ljiljana Stošić Mihajlović

    2014-07-01

    Full Text Available Marketing channel is a set of entities and institutions, completion of distribution and marketing activities, attend the efficient and effective networking of producers and consumers. Marketing channels include the total flows of goods, money and information taking place between the institutions in the system of marketing, establishing a connection between them. The functions of the exchange, the physical supply and service activities, inherent in the system of marketing and trade. They represent paths which products and services are moving after the production, which will ultimately end up buying and eating by the user.

  1. Topic Detection Based on Weak Tie Analysis: A Case Study of LIS Research

    Directory of Open Access Journals (Sweden)

    Ling Wei

    2016-11-01

    Full Text Available Purpose: Based on the weak tie theory, this paper proposes a series of connection indicators of weak tie subnets and weak tie nodes to detect research topics, recognize their connections, and understand their evolution. Design/methodology/approach: First, keywords are extracted from article titles and preprocessed. Second, high-frequency keywords are selected to generate weak tie co-occurrence networks. By removing the internal lines of clustered sub-topic networks, we focus on the analysis of weak tie subnets' composition and functions and the weak tie nodes' roles. Findings: The research topics' clusters and themes changed yearly; the subnets clustered with technique-related and methodology-related topics have been the core, important subnets for years; while close subnets are highly independent, research topics are generally concentrated and most topics are application-related; the roles and functions of nodes and weak ties are diversified. Research limitations: The parameter values are somewhat inconsistent; the weak tie subnets and nodes are classified based on empirical observations, and the conclusions are not verified or compared to other methods. Practical implications: The research is valuable for detecting important research topics as well as their roles, interrelations, and evolution trends. Originality/value: To contribute to the strength of weak tie theory, the research translates weak and strong ties concepts to co-occurrence strength, and analyzes weak ties' functions. Also, the research proposes a quantitative method to classify and measure the topics' clusters and nodes.

  2. Integrating Micro-level Interactions with Social Network Analysis in Tie Strength Research

    DEFF Research Database (Denmark)

    Torre, Osku; Gupta, Jayesh Prakash; Kärkkäinen, Hannu

    2017-01-01

    of tie strength based on reciprocal interaction from publicly available Facebook data, and suggest that this approach could work as a basis for further tie strength studies. Our approach makes use of weak tie theory, and enables researchers to study micro-level interactions (i.e. discussions, messages......A social tie is a target for ongoing, high-level scientific debate. Measuring the tie strength in social networks has been an important topic for academic studies since Mark Granovetter's seminal papers in 1970's. However, it is still a problematic issue mainly for two reasons: 1) existing tie...... strengthening process in online social networks. Therefore, we suggest a new approach to tie strength research, which focuses on studying communication patterns (edges) more rather than actors (nodes) in a social network. In this paper we build a social network analysis-based approach to enable the evaluation...

  3. Ties That Bind: Creating and sustaining community-academic partnerships

    Directory of Open Access Journals (Sweden)

    Kynna N. Wright

    2011-11-01

    Full Text Available Growing interest among academics and health professionals in finding new ways to study and address complex health and social problems has manifested in recent years with increasing community demands for research and program implementation that is community-based, rather than merely community placed. In the United States, community-based participatory research (CBPR, with its emphasis on the creation and use of community-university or community-academic partnerships, is the prevailing paradigm to address these complex problems, especially those concerning racial/ethnic disparities in health and health care. While the need to strengthen the relationship between researchers and the community has been recognised, often from the viewpoint of the university partner, discussions on sustainability of partnerships have been few. The aim of this paper is to share reflections, through the eyes of the community members, on the core elements that tie community and academic members together and the challenges in understanding and nurturing those ties so that the community-academic partnership is sustained over time, and to offer possible recommendations for sustainability. This article speaks from the community’s perspective and reflects on the vital elements/components that tie together community-university partnerships and the challenges that may occur when trying to sustain and grow the partnership. It is based on a research CBPR study that was conducted to (1 evaluate the functioning and future sustainability of the community-university partnership of the Community Child Health Network Study Los Angeles (CCHN-LA community-university partnership, and (2 evaluate the experience and beliefs of the current CCHN-LA community-university partnership members in their understanding of current functioning. Keywords Community-academic partnerships; sustainability; challenges; solutions

  4. Tongue-tie, from embriology to treatment: a literature review

    Directory of Open Access Journals (Sweden)

    Maria Dezio

    2015-03-01

    Full Text Available The aim of this review is to create a complete analysis about tongue-tie (or short lingual frenum or ankyloglossia according to the most important works published in literature. The analysis allowed us to do a complete evaluation of this problem, from embriology to the therapeutic approach we could use today, focusing our attention on laser-assisted therapy. This review is based on the research on the PubMed Database (www.ncbi.nlm.nih.gov of studies about lingual frenum written in English between January 1980 and May 2014. The keywords inserted were “lingual frenum”, “frenectomy”, “laser therapy”. We have analyzed: case series, case reports, clinical studies, and also literature reviews in which embryology, physiology, diagnosis and treatment of ankyloglossia were described. We excluded laboratory studies, studies based on animal tests and studies about patients with particular syndromes in which we can also find tongue-tie. The selection criteria allowed us to select 42 articles. The treatment options for the releasing of the frenum are surgically represented by frenotomy (i.e. simple horizontal cut of this training and frenectomy (i.e. removal. In both cases, the intervention on the short lingual frenum is simple, short-lasting, and without particular complications. Furthermore, this kind of treatment can be carried out with different devices: with the typical cold blade scalpel or by the use of laser, a new method that shows more advantages over the prior art. Laser-assisted therapy permits to intervene on newborns (from 0 to 20 days, when there are breastfeeding problems without total anesthesia and suture. The Er:YAG, CO2 laser (according to literature data and Diode laser (according to our experience are advantageous, safe and effective in tongue-tie treatment.

  5. Urban characteristics attributable to density-driven tie formation

    Science.gov (United States)

    Pan, Wei; Ghoshal, Gourab; Krumme, Coco; Cebrian, Manuel; Pentland, Alex

    2013-06-01

    Motivated by empirical evidence on the interplay between geography, population density and societal interaction, we propose a generative process for the evolution of social structure in cities. Our analytical and simulation results predict both super-linear scaling of social-tie density and information contagion as a function of the population. Here we demonstrate that our model provides a robust and accurate fit for the dependency of city characteristics with city-size, ranging from individual-level dyadic interactions (number of acquaintances, volume of communication) to population level variables (contagious disease rates, patenting activity, economic productivity and crime) without the need to appeal to heterogeneity, modularity, specialization or hierarchy.

  6. Intergenerational family ties and the diffusion of cohabitation in Italy

    Directory of Open Access Journals (Sweden)

    Alessandro Rosina

    2007-05-01

    Full Text Available Cohabitation has been spreading in the population during the last thirty years, and this is one of the most striking aspects of wider social changes that have taken place throughout the industrialized world. However, this change did not take place uniformly across Europe. The purpose of this paper is to contribute to the current debate around the compatibility of cohabitation experiences with the Italian cultural context. Using an individual-level diffusion approach we obtain results that are consistent with the crucial role that family ties play in the choice of cohabitation in place of (or before marriage.

  7. Contact dermatitis in tie and dye industry workers

    Energy Technology Data Exchange (ETDEWEB)

    Mathur, N K; Mathur, A; Banerjee, K

    1985-01-01

    A survey of the Tie and Dye industry of Jodhpur City in India was made to investigate occupational dermatoses. 49 (16.6%) of 250 workers had incapacitating dermatitis. Skin lesions were seen mostly over the dorsa of the hands and fingers. 26 patients were patch tested with various dyes and chemicals; 14 were positive. Fast Red RC salt was the most potent sensitizer. Other dyes showing positive reactions were Orange GC salt, Bordeaux GP salt, Blue B salt, Red B base and naphthol.

  8. The ties that bind: Ingroup ties are linked with diminished inflammatory immune responses and fewer mental health symptoms through less rumination.

    Science.gov (United States)

    Ysseldyk, Renate; McQuaid, Robyn J; McInnis, Opal A; Anisman, Hymie; Matheson, Kimberly

    2018-01-01

    The present research explored whether components of social identity, namely ingroup ties, affect, and centrality, were differentially linked to mental health and inflammatory immune responses, and whether rumination mediated those relations. Study 1 (N = 138) indicated that stronger ingroup ties were associated with fewer mental health (depressive and post-traumatic stress) symptoms; those relations were mediated by the tendency for individuals with strong ties to rely less on ruminative coping to deal with a stressful life event. Study 2 (N = 54) demonstrated that ingroup ties were negatively associated with depressive symptoms, dispositional rumination, as well as stress-linked inflammatory elements at the physiological level. Consistent associations for centrality and ingroup affect were absent, suggesting that ingroup ties may have unique health benefits.

  9. Beaver dams and channel sediment dynamics on Odell Creek, Centennial Valley, Montana, USA

    Science.gov (United States)

    Levine, Rebekah; Meyer, Grant A.

    2014-01-01

    Beaver dams in streams are generally considered to increase bed elevation through in-channel sediment storage, thus, reintroductions of beaver are increasingly employed as a restoration tool to repair incised stream channels. Here we consider hydrologic and geomorphic characteristics of the study stream in relation to in-channel sediment storage promoted by beaver dams. We also document the persistence of sediment in the channel following breaching of dams. Nine reaches, containing 46 cross-sections, were investigated on Odell Creek at Red Rock Lakes National Wildlife Refuge, Centennial Valley, Montana. Odell Creek has a snowmelt-dominated hydrograph and peak flows between 2 and 10 m3 s- 1. Odell Creek flows down a fluvial fan with a decreasing gradient (0.018-0.004), but is confined between terraces along most of its length, and displays a mostly single-thread, variably sinuous channel. The study reaches represent the overall downstream decrease in gradient and sediment size, and include three stages of beaver damming: (1) active; (2) built and breached in the last decade; and (3) undammed. In-channel sediment characteristics and storage were investigated using pebble counts, fine-sediment depth measurements, sediment mapping and surveys of dam breaches. Upstream of dams, deposition of fine (≤ 2 mm) sediment is promoted by reduced water surface slope, shear stress and velocity, with volumes ranging from 48 to 182 m3. High flows, however, can readily transport suspended sediment over active dams. Variations in bed-sediment texture and channel morphology associated with active dams create substantial discontinuities in downstream trends and add to overall channel heterogeneity. Observations of abandoned dam sites and dam breaches revealed that most sediment stored above beaver dams is quickly evacuated following a breach. Nonetheless, dam remnants trap some sediment, promote meandering and facilitate floodplain development. Persistence of beaver dam sediment

  10. Influence of Beaver Dams on Channel Complexity, Hydrology, and Temperature Regime in a Mountainous Stream

    Science.gov (United States)

    Majerova, M.; Neilson, B. T.; Schmadel, N. M.; Wheaton, J. M.; Snow, C. J.

    2013-12-01

    Beaver dams and beaver activity affect hydrologic processes, sediment transport, channel complexity and water quality of streams. Beaver ponds, which form behind beaver dams, increase in-channel water storage affecting the timing and volume of flow and resulting in the attenuation and flattening of the hydrograph. Channel complexity also increases the potential for transient storage (both surface and subsurface) and influences stream temperature. Impacts of beaver dams and beaver activity on stream responses are difficult to quantify because responses are dynamic and spatially variable. Few studies have focused on the reach scale temporal influences on stream responses and further research is needed particularly in quantifying the influence of beaver dams and their role in shaping the stream habitat. This study explores the changing hydrology and temperature regime of Curtis Creek, a mountainous stream located in Northern Utah, in a 560 m long reach where groundwater exchanges and temperature differences were observed over a three-year period. We have collected continuous stream discharge, stream temperature data and performed tracer experiments. During the first year, we were able to capture the pre-beaver activity. In the second year, we captured the impacts of some beaver activity with only a few dams built in the reach, while the third year included the effects of an entire active beaver colony. By the end of the study period, a single thread channel had been transformed into a channel with side channels and backwaters at multiple locations therefore increasing channel complexity. The cumulative influence of beaver dams on reach scale discharge resulted in a slightly losing reach that developed into a gaining reach. At the smaller sub-reach scale, both losing to gaining and gaining to losing transformations were observed. Temperature differences showed a warming effect of beaver dams at the reach scale. The reach stream temperature difference increased on

  11. Channel Power in Multi-Channel Environments

    NARCIS (Netherlands)

    M.G. Dekimpe (Marnik); B. Skiera (Bernd)

    2004-01-01

    textabstractIn the literature, little attention has been paid to instances where companies add an Internet channel to their direct channel portfolio. However, actively managing multiple sales channels requires knowing the customers’ channel preferences and the resulting channel power. Two key

  12. Organizing learning processes on risks by using the bow-tie representation

    Energy Technology Data Exchange (ETDEWEB)

    Chevreau, F.R. [Ecole des Mines de Paris, 06904 Sophia-Antipolis (France)]. E-mail: chevreau@cindy.ensmp.fr; Wybo, J.L. [Ecole des Mines de Paris, 06904 Sophia-Antipolis (France)]. E-mail: wybo@cindy.ensmp.fr; Cauchois, D. [Process Safety Department, Sanofi-Aventis, Site de Production de Vitry sur Seine, 9 Quai Jules Guesdes, 94400 Vitry sur Seine (France)]. E-mail: didier.cauchois@sanofi-aventis.com

    2006-03-31

    The Aramis method proposes a complete and efficient way to manage risk analysis by using the bow-tie representation. This paper shows how the bow-tie representation can also be appropriate for experience learning. It describes how a pharmaceutical production plant uses bow-ties for incident and accident analysis. Two levels of bow-ties are constructed: standard bow-ties concern generic risks of the plant whereas local bow-ties represent accident scenarios specific to each workplace. When incidents or accidents are analyzed, knowledge that is gained is added to existing local bow-ties. Regularly, local bow-ties that have been updated are compared to standard bow-ties in order to revise them. Knowledge on safety at the global and at local levels is hence as accurate as possible and memorized in a real time framework. As it relies on the communication between safety experts and local operators, this use of the bow-ties contributes therefore to organizational learning for safety.

  13. Organizing learning processes on risks by using the bow-tie representation

    International Nuclear Information System (INIS)

    Chevreau, F.R.; Wybo, J.L.; Cauchois, D.

    2006-01-01

    The Aramis method proposes a complete and efficient way to manage risk analysis by using the bow-tie representation. This paper shows how the bow-tie representation can also be appropriate for experience learning. It describes how a pharmaceutical production plant uses bow-ties for incident and accident analysis. Two levels of bow-ties are constructed: standard bow-ties concern generic risks of the plant whereas local bow-ties represent accident scenarios specific to each workplace. When incidents or accidents are analyzed, knowledge that is gained is added to existing local bow-ties. Regularly, local bow-ties that have been updated are compared to standard bow-ties in order to revise them. Knowledge on safety at the global and at local levels is hence as accurate as possible and memorized in a real time framework. As it relies on the communication between safety experts and local operators, this use of the bow-ties contributes therefore to organizational learning for safety

  14. Poor textural image tie point matching via graph theory

    Science.gov (United States)

    Yuan, Xiuxiao; Chen, Shiyu; Yuan, Wei; Cai, Yang

    2017-07-01

    Feature matching aims to find corresponding points to serve as tie points between images. Robust matching is still a challenging task when input images are characterized by low contrast or contain repetitive patterns, occlusions, or homogeneous textures. In this paper, a novel feature matching algorithm based on graph theory is proposed. This algorithm integrates both geometric and radiometric constraints into an edge-weighted (EW) affinity tensor. Tie points are then obtained by high-order graph matching. Four pairs of poor textural images covering forests, deserts, bare lands, and urban areas are tested. For comparison, three state-of-the-art matching techniques, namely, scale-invariant feature transform (SIFT), speeded up robust features (SURF), and features from accelerated segment test (FAST), are also used. The experimental results show that the matching recall obtained by SIFT, SURF, and FAST varies from 0 to 35% in different types of poor textures. However, through the integration of both geometry and radiometry and the EW strategy, the recall obtained by the proposed algorithm is better than 50% in all four image pairs. The better matching recall improves the number of correct matches, dispersion, and positional accuracy.

  15. Dynamic risk analysis using bow-tie approach

    International Nuclear Information System (INIS)

    Khakzad, Nima; Khan, Faisal; Amyotte, Paul

    2012-01-01

    Accident probability estimation is a common and central step to all quantitative risk assessment methods. Among many techniques available, bow-tie model (BT) is very popular because it represent the accident scenario altogether including causes and consequences. However, it suffers a static structure limiting its application in real-time monitoring and probability updating which are key factors in dynamic risk analysis. The present work is focused on using BT approach in a dynamic environment in which the occurrence probability of accident consequences changes. In this method, on one hand, failure probability of primary events of BT, leading to the top event, are developed using physical reliability models, and constantly revised as physical parameters (e.g., pressure, velocity, dimension, etc) change. And, on the other hand, the failure probability of safety barriers of the BT are periodically updated using Bayes’ theorem as new information becomes available over time. Finally, the resulting, updated BT is used to estimate the posterior probability of the consequences which in turn results in an updated risk profile. - Highlights: ► A methodology is proposed to make bow-tie method adapted for dynamic risk analysis. ► Physical reliability models are used to revise the top event. ► Bayes’ theorem is used to update the probability of safety barriers. ► The number of accidents in sequential time intervals is used to form likelihood function. ► The risk profile is updated for varying physical parameters and for different times.

  16. Infectious disease research investments follow colonial ties: questionable ethics.

    Science.gov (United States)

    Fitchett, Joseph R; Head, Michael G; Atun, Rifat

    2014-03-01

    International funding for global health research is not systematically documented. We have assessed the level of research funding awarded by UK funders of international research to low- and middle-income countries or research institutions in these countries. We analysed 6165 studies; from these we selected 522 that matched our criteria and used them to evaluate research funding by pathogen, disease, research and development value chain, funding organisation and country. Investment in infectious disease research in the countries studied totalled £264 million. Distribution of research investments closely mirrored that of the UK's former colonial territories; the top five countries, and eight of the top 10, have historical links with the UK, being current or former members of the Commonwealth of Nations. HIV, malaria and neglected tropical diseases attracted the greatest investment (£219 million; 82.8%), with most studies focussing on operational and epidemiological research (£109 million; 41.3%). International financing of infectious disease research by UK funding organisations follows former colonial ties. Funding institutions should review their funding policies to ensure that they also assist low- and middle-income countries without colonial ties to address their disease burden. A global investment surveillance system is needed to map and monitor funding for international research and guide the allocation of scarce resources to reduce the global disease burden.

  17. 78 FR 75544 - Prestressed Concrete Steel Rail Tie Wire From Mexico: Preliminary Determination of Sales at Less...

    Science.gov (United States)

    2013-12-12

    ... DEPARTMENT OF COMMERCE International Trade Administration [A-201-843] Prestressed Concrete Steel...'') preliminarily determines that prestressed concrete steel rail tie wire (``PC tie wire'') from Mexico is being... element levels; suitable for use as prestressed tendons in concrete railroad ties (``PC tie wire''). High...

  18. 78 FR 29325 - Prestressed Concrete Steel Rail Tie Wire From Mexico, the People's Republic of China, and...

    Science.gov (United States)

    2013-05-20

    ...] Prestressed Concrete Steel Rail Tie Wire From Mexico, the People's Republic of China, and Thailand: Initiation... of prestressed concrete steel rail tie wire (``PC tie wire'') from Mexico, the PRC, and Thailand... Prestressed Concrete Steel Rail Tie Wire from the PRC, Mexico, and Thailand, filed on April 23, 2013 (the...

  19. Fuel assembly and fuel channel box

    International Nuclear Information System (INIS)

    Sakuma, Toraki; Hirakawa, Hiromasa; Ishizaki, Hideaki; Nakajima, Junjiro; Aizawa, Yasuhiro.

    1992-01-01

    A fuel channel box has a square cylindrical shape and, in the transversal cross sectional shape, the wall thickness of a corner portion is greater than that of a central portion of the side wall except for an upper portion thereof. The upper portion of the channel box includes a region to be in contact with an upper lattice plate and a region to attach a channel spacer. Then, the wall thickness of these regions is uniform in the transversal cross section and they have the same wall thickness with that of the corner portion which has the increased wall thickness. With such a constitution, the upper portion of the channel box receives a counter force applied from the upper lattice plate upon occurrence of earthquakes and moderate it to reduce local stresses and deformation. Further, a similar region with increased wall thickness is disposed also to the lower portion of the channel box, thereby enabling to suppress the amount of coolants leaked from a portion between the lower portion and a lower tie plate, and improve the mechanical integrity of the channel box. (I.N.)

  20. The role of feedback mechanisms in historic channel changes of the lower Rio Grande in the Big Bend region

    Science.gov (United States)

    Dean, David J.; Schmidt, John C.

    2011-03-01

    flood was reduced between 40 and 50%, over-bank flooding continued. These changes reflect a shift in the geomorphic nature of the Rio Grande from a wide, laterally unstable, multi-thread river, to a laterally stable, single-thread channel with cohesive, vertical banks, and few active in-channel bars.

  1. Studi Tentang Political Tie, Pengaruhnya Terhadap Keputusan Pemberian Kredit Bank di Indonesia

    Directory of Open Access Journals (Sweden)

    Elisa Tjondro

    2012-01-01

    Full Text Available This study uses bank loan data to examine the effect of (political tie between the company and the government to on the assessment of companies financial leverage and profitability in the bank lending decisions in Indonesia. The numbers of samples are 1465 observations. This study uses moderated regression analysis (MRA. The study finds that a political tie affect corporate profitability assessment in bank lending decisions. Firms with lower profitability receive larger bank loan because their political tie (rent-seeking hypothesis. However, this study inds that a political tie does not affect the assessment of financial leverage in bank's lending decisions. This finding also supports Faccio (2010, Fisman (2001, and Backman (2001. Indonesia condition which has a weak institutional regulation and high information asymmetry is beneficial for companies that have a political tie. This leads to more trusted political tie as an indicator of the profitability.

  2. Importance of tie strengths in the prisoner's dilemma game on social networks

    International Nuclear Information System (INIS)

    Xu, Bo; Liu, Lu; You, Weijia

    2011-01-01

    Though numerous researches have shown that tie strengths play a key role in the formation of collective behavior in social networks, little work has been done to explore their impact on the outcome of evolutionary games. In this Letter, we studied the effect of tie strength in the dynamics of evolutionary prisoner's dilemma games by using online social network datasets. The results show that the fraction of cooperators has a non-trivial dependence on tie strength. Weak ties, just like previous researches on epidemics and information diffusion have shown, play a key role by the maintenance of cooperators in evolutionary prisoner's dilemma games. -- Highlights: → Tie strength is used to measure heterogeneous influences of different pairs of nodes. → Weak ties play a role in maintaining cooperation in prisoner's dilemma games. → Micro-dynamics of nodes are illustrated to explain the conclusion.

  3. Importance of tie strengths in the prisoner's dilemma game on social networks

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Bo, E-mail: xubosuper@163.com [Department of Information Systems, School of Economics and Management, Beihang University (China); Liu, Lu; You, Weijia [Department of Information Systems, School of Economics and Management, Beihang University (China)

    2011-06-13

    Though numerous researches have shown that tie strengths play a key role in the formation of collective behavior in social networks, little work has been done to explore their impact on the outcome of evolutionary games. In this Letter, we studied the effect of tie strength in the dynamics of evolutionary prisoner's dilemma games by using online social network datasets. The results show that the fraction of cooperators has a non-trivial dependence on tie strength. Weak ties, just like previous researches on epidemics and information diffusion have shown, play a key role by the maintenance of cooperators in evolutionary prisoner's dilemma games. -- Highlights: → Tie strength is used to measure heterogeneous influences of different pairs of nodes. → Weak ties play a role in maintaining cooperation in prisoner's dilemma games. → Micro-dynamics of nodes are illustrated to explain the conclusion.

  4. Representation of Women With Industry Ties in Ophthalmology.

    Science.gov (United States)

    Reddy, Ashvini K; Bounds, Gregory W; Bakri, Sophie J; Gordon, Lynn K; Smith, Justine R; Haller, Julia A; Thorne, Jennifer E

    2016-06-01

    Women in ophthalmology are growing in number and have made strides in traditional metrics of professional achievement. Professional ties to industry represent another potential means of career advancement, recognition, and income. To report the representation of women among ophthalmologists receiving industry remuneration for research, consulting, honoraria, grants, royalties, and faculty/speaker roles. In this observational, retrospective study, the Centers for Medicare and Medicaid Services Open Payments database for payments to ophthalmologists by biomedical companies was reviewed for representation, median payments, and mean payments by women and men for industry relationships in 2013 and 2014. The analysis was performed from July 2015 to November 2015. The primary outcome measures were percentage representation of women vs men overall and in industry research, consulting, speaking roles, royalties and licenses, grants, services other than consulting, and honoraria. Secondary outcome measures included mean and median payments from industry to female vs male ophthalmologists. In 2013, 4164 of 21 380 (19.5%) ophthalmologists were women, and of 1204 ophthalmologists analyzed for industry payments, 176 (4.2%) women had industry ties compared with 1028 (6%) men (P women were $11 419 compared with $20 957 for men (P = .001), and median payments to women were $3000 compared with $4787 for men (P = .007). In 2013, women were underrepresented among ophthalmologists receiving industry payments for research (49 of 462 [10.6%]), consulting (96 of 610 [15.7%]), honoraria (3 of 47 [6.4%]), industry grants (1 of 7 [14.3%]), royalties and licenses (1 of 13 [7.7%]), and faculty/speaker roles (2 of 48 [4.2%]). In 2014, 4352 of 21 531 (20.2%) of ophthalmologists were women. Of 1518 ophthalmologists analyzed for industry payments, 255 (6%) women had industry ties compared with 1263 (7.4%) men (P women were $14 848 compared with $30 513 for men (P = .004

  5. Performance and Characterization of Shear Ties for Use in Insulated Precast Concrete Sandwich Wall Panels

    Science.gov (United States)

    2010-11-01

    stainless 14 steel, galvanized carbon steel, carbon- fiber -reinforced polymer (CFRP), glass- fiber -reinforced polymer 15 (GFRP), and basalt - fiber ...CFRP Grid, (E) Universal Building Products GFRP Teplo Tie, and (F) Universal Building Products 6 Basalt FRP RockBar. Traditional steel connections...1.6 E Universal Building Products TeploTie GFRP Tie 10 mm dia. x 150 mm F RockBar Basalt FRP Bar 7 in. x 5/16 in. G TSA Manufacturing C-Clip

  6. Importance of tie strengths in the prisoner's dilemma game on social networks

    Science.gov (United States)

    Xu, Bo; Liu, Lu; You, Weijia

    2011-06-01

    Though numerous researches have shown that tie strengths play a key role in the formation of collective behavior in social networks, little work has been done to explore their impact on the outcome of evolutionary games. In this Letter, we studied the effect of tie strength in the dynamics of evolutionary prisoner's dilemma games by using online social network datasets. The results show that the fraction of cooperators has a non-trivial dependence on tie strength. Weak ties, just like previous researches on epidemics and information diffusion have shown, play a key role by the maintenance of cooperators in evolutionary prisoner's dilemma games.

  7. Temperature Profile in Fuel and Tie-Tubes for Nuclear Thermal Propulsion Systems

    Energy Technology Data Exchange (ETDEWEB)

    Vishal Patel

    2015-02-01

    A finite element method to calculate temperature profiles in heterogeneous geometries of tie-tube moderated LEU nuclear thermal propulsion systems and HEU designs with tie-tubes is developed and implemented in MATLAB. This new method is compared to previous methods to demonstrate shortcomings in those methods. Typical methods to analyze peak fuel centerline temperature in hexagonal geometries rely on spatial homogenization to derive an analytical expression. These methods are not applicable to cores with tie-tube elements because conduction to tie-tubes cannot be accurately modeled with the homogenized models. The fuel centerline temperature directly impacts safety and performance so it must be predicted carefully. The temperature profile in tie-tubes is also important when high temperatures are expected in the fuel because conduction to the tie-tubes may cause melting in tie-tubes, which may set maximum allowable performance. Estimations of maximum tie-tube temperature can be found from equivalent tube methods, however this method tends to be approximate and overly conservative. A finite element model of heat conduction on a unit cell can model spatial dependence and non-linear conductivity for fuel and tie-tube systems allowing for higher design fidelity of Nuclear Thermal Propulsion.

  8. Strengthening weak ties through on-line gaming

    DEFF Research Database (Denmark)

    Sudzina, Frantisek; Razmerita, Liana Virginia; Kirchner, Kathrin

    On-line gaming became widespread in the last couple of years. The aim of the research presented in the paper is to figure out to what extent does game playing helps to strengthen weak ties and what additional factors influence this process. The approach is rather exploratory – some factors...... are grounded in theory, some are new. These factors are age, gender, place of origin, number of their Facebook connections (friends in Facebook terminology), the amount of time they are on Facebook, the amount of time they keep the Facebook site open, the amount of time they play on-line games, and the reasons...... for starting to play on-line games. Regarding the latter, we chose to focus only on escapist reasons....

  9. Cooperation prevails when individuals adjust their social ties.

    Directory of Open Access Journals (Sweden)

    Francisco C Santos

    2006-10-01

    Full Text Available Conventional evolutionary game theory predicts that natural selection favours the selfish and strong even though cooperative interactions thrive at all levels of organization in living systems. Recent investigations demonstrated that a limiting factor for the evolution of cooperative interactions is the way in which they are organized, cooperators becoming evolutionarily competitive whenever individuals are constrained to interact with few others along the edges of networks with low average connectivity. Despite this insight, the conundrum of cooperation remains since recent empirical data shows that real networks exhibit typically high average connectivity and associated single-to-broad-scale heterogeneity. Here, a computational model is constructed in which individuals are able to self-organize both their strategy and their social ties throughout evolution, based exclusively on their self-interest. We show that the entangled evolution of individual strategy and network structure constitutes a key mechanism for the sustainability of cooperation in social networks. For a given average connectivity of the population, there is a critical value for the ratio W between the time scales associated with the evolution of strategy and of structure above which cooperators wipe out defectors. Moreover, the emerging social networks exhibit an overall heterogeneity that accounts very well for the diversity of patterns recently found in acquired data on social networks. Finally, heterogeneity is found to become maximal when W reaches its critical value. These results show that simple topological dynamics reflecting the individual capacity for self-organization of social ties can produce realistic networks of high average connectivity with associated single-to-broad-scale heterogeneity. On the other hand, they show that cooperation cannot evolve as a result of "social viscosity" alone in heterogeneous networks with high average connectivity, requiring the

  10. Channelling and electromagnetic radiation of channelling particles

    International Nuclear Information System (INIS)

    Kalashnikov, N.

    1983-01-01

    A brief description is presented of the channelling of charged particles between atoms in the crystal lattice. The specificities are discussed of the transverse motion of channelling particles as are the origin and properties of quasi-characteristic radiation of channelling particles which accompany transfers from one band of permissible energies of the transverse motion of channelling particles to the other. (B.S.)

  11. Channel Modeling

    Science.gov (United States)

    Schmitz, Arne; Schinnenburg, Marc; Gross, James; Aguiar, Ana

    For any communication system the Signal-to-Interference-plus-Noise-Ratio of the link is a fundamental metric. Recall (cf. Chapter 9) that the SINR is defined as the ratio between the received power of the signal of interest and the sum of all "disturbing" power sources (i.e. interference and noise). From information theory it is known that a higher SINR increases the maximum possible error-free transmission rate (referred to as Shannon capacity [417] of any communication system and vice versa). Conversely, the higher the SINR, the lower will be the bit error rate in practical systems. While one aspect of the SINR is the sum of all distracting power sources, another issue is the received power. This depends on the transmitted power, the used antennas, possibly on signal processing techniques and ultimately on the channel gain between transmitter and receiver.

  12. Channeling experiment

    International Nuclear Information System (INIS)

    Abelin, H.; Birgersson, L.; Widen, H.; Aagren, T.; Moreno, L.; Neretnieks, I.

    1990-07-01

    Channeling of water flow and tracer transport in real fractures in a granite body at Stripa have been investigated experimentally. The experimental site was located 360 m below the ground level. Two kinds of experiments were performed. In the single hole experiments, 20 cm diameter holes were drilled about 2.5 m into the rock in the plane of the fracture. Specially designed packers were used to inject water into the fracture in 5 cm intervals all along the fracture trace in the hole. The variation of the injection flowrates along the fracture were used to determine the transmissivity variations in the fracture plane. Detailed photographs were taken from inside the hole and the visual fracture aperture was compared with the injection flowrates in the same locations. Geostatistical methods were used to evaluate the results. Five holes were measured in great detail. In addition 7 holes were drilled and scanned by simpler packer systems. A double hole experiment was performed where two parallel holes were drilled in the same fracture plane at nearly 2 m distance. Pressure pulse tests were made between the holes in both directions. Tracers were injected in 5 locations in one hole and monitored for in many locations in the other hole. The single hole experiment and the double hole experiment show that most of the fracture planes are tight but that there are open sections which form connected channels over distances of at least 2 meters. It was also found in the double hole experiment that the investigated fracture was intersected by at least one fracture between the two holes which diverted a large amount of the injected tracers to several distant locations at the tunnel wall. (authours)

  13. Effects of a Group Intervention on the Career Network Ties of Finnish Adolescents

    Science.gov (United States)

    Jokisaari, Markku; Vuori, Jukka

    2011-01-01

    The authors evaluated how a group-based career intervention affected career network ties among Finnish adolescents as they made educational choices and prepared for their transition to secondary education. They examined the career-related network ties of 868 students during their last year in comprehensive school (junior high school) in a…

  14. Polycyclic aromatic hydrocarbon migration from creosote-treated railway ties into ballast and adjacent wetlands

    Science.gov (United States)

    Kenneth M. Brooks

    2004-01-01

    Occasionally, creosote-treated railroad ties need to be replaced, sometimes in sensitive environments such as wetlands. To help determine if this is detrimental to the surrounding environment, more information is needed on the extent and pattern of creosote, or more specifically polycyclic aromatic hydrocarbon (PAH), migration from railroad ties and what effects this...

  15. The Bright Side and Dark Side of Embedded Ties In Business-to-Business Innovation

    NARCIS (Netherlands)

    C.S. Noordhoff (Corine); K. Kyriakopoulos (Kyriakos); C. Moorman (Christina); P. Pauwels (Pieter); B.G.C. Dellaert (Benedict)

    2011-01-01

    textabstractWhile the number and importance of joint innovation projects between suppliers and their customers continue to rise, the literature has yet to resolve a key question—do embedded ties with customers help or hurt supplier innovation? Drawing on both the tie strength and knowledge

  16. The bright side and dark side of embedded ties in business-to-business innovation

    NARCIS (Netherlands)

    C.S. Noordhoff (Corine); K. Kyriakopoulos (Kyriakos); C. Moorman (Christina); P. Pauwels (Pieter); B.G.C. Dellaert (Benedict)

    2011-01-01

    textabstractAlthough the number and importance of joint innovation projects between suppliers and their customers continue to rise, the literature has yet to resolve a key question: Do embedded ties with customers help or hurt supplier innovation? Drawing on both the tie strength and knowledge

  17. The use of nylon cable ties to repair rib fractures in neonatal foals

    OpenAIRE

    Downs, Chris; Rodgerson, Dwayne

    2011-01-01

    Commercially available nylon cable ties were used as a method of internal fixation for displaced rib fractures in 8 equine neonates. The procedure was effective, well-tolerated, rapid, and inexpensive. The use of nylon cable ties as internal fixation for displaced rib fractures in foals is an effective surgical procedure.

  18. Experimental Effects of Program Management Approach on Teachers' Professional Ties and Social Capital

    Science.gov (United States)

    Quinn, David M.; Kim, James S.

    2018-01-01

    Theory and empirical work suggest that teachers' social capital influences school improvement efforts. Social ties are prerequisite for social capital, yet little causal evidence exists on how malleable factors, such as instructional management approaches, affect teachers' ties. In this cluster-randomized trial, we apply a decision-making…

  19. Social Identity, Social Ties and Social Capital: A Study in Gaming Context

    Science.gov (United States)

    Jiang, Hao

    2012-01-01

    This work will focus on how different social relationships, namely shared identity and personal tie, will impact cooperative behavior, a form of social capital. I designed and conducted an economic game study to show that shared identity and personal ties work differently on cooperation among people and resource flow in social groups. Many factors…

  20. Neural dynamics of social tie formation in economic decision-making.

    Science.gov (United States)

    Bault, Nadège; Pelloux, Benjamin; Fahrenfort, Johannes J; Ridderinkhof, K Richard; van Winden, Frans

    2015-06-01

    The disposition for prosocial conduct, which contributes to cooperation as arising during social interaction, requires cortical network dynamics responsive to the development of social ties, or care about the interests of specific interaction partners. Here, we formulate a dynamic computational model that accurately predicted how tie formation, driven by the interaction history, influences decisions to contribute in a public good game. We used model-driven functional MRI to test the hypothesis that brain regions key to social interactions keep track of dynamics in tie strength. Activation in the medial prefrontal cortex (mPFC) and posterior cingulate cortex tracked the individual's public good contributions. Activation in the bilateral posterior superior temporal sulcus (pSTS), and temporo-parietal junction was modulated parametrically by the dynamically developing social tie-as estimated by our model-supporting a role of these regions in social tie formation. Activity in these two regions further reflected inter-individual differences in tie persistence and sensitivity to behavior of the interaction partner. Functional connectivity between pSTS and mPFC activations indicated that the representation of social ties is integrated in the decision process. These data reveal the brain mechanisms underlying the integration of interaction dynamics into a social tie representation which in turn influenced the individual's prosocial decisions. © The Author (2014). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

  1. 78 FR 25303 - Prestressed Concrete Steel Rail Tie Wire From China, Mexico, and Thailand

    Science.gov (United States)

    2013-04-30

    ... INTERNATIONAL TRADE COMMISSION [Investigation Nos. 731-TA-1207-1209 (Preliminary)] Prestressed Concrete Steel Rail Tie Wire From China, Mexico, and Thailand Institution of antidumping duty..., by reason of imports from prestressed concrete steel rail tie wire from China, Mexico, and Thailand...

  2. 78 FR 37236 - Prestressed Concrete Steel Rail Tie Wire From China, Mexico, and Thailand

    Science.gov (United States)

    2013-06-20

    ... Concrete Steel Rail Tie Wire From China, Mexico, and Thailand Determinations On the basis of the record \\1... imports from China, Mexico, and Thailand of prestressed concrete steel rail tie wire, provided for in... China, Mexico, and Thailand. Accordingly, effective April 23, 2013, the Commission instituted...

  3. The VEGF system and tie-2 are spatio-temporal expressed during tayassu placentation

    DEFF Research Database (Denmark)

    Miglino, M.A.; Santos, T.C.; Papa, P.C.

    Objectives: The vascular endothelial growth factor (VEGF) is one of the most important vascular mitogens, while the angiotensin receptor Tie-2 binds to the angiopoietin and stabilizes newly formed vessels. We therefore wanted to localize VEGF and its receptors VEGF-R1, VEGF-R2 and the Tie-2 recep...

  4. 75 FR 34941 - Review of the Commission's Program Access Rules and Examination of Programming Tying Arrangements

    Science.gov (United States)

    2010-06-21

    ... Commission's Program Access Rules and Examination of Programming Tying Arrangements AGENCY: Federal... Program Access Rules and Examination of Programming Tying Arrangements, MB Docket No. 07-198, FCC 10-17... information collection is contained in Sections 4(i), 303(r), and 628 of the Communications Act of 1934, as...

  5. Dual market structures and the likelihood of repeated ties - evidence from pharmaceutical biotechnology

    NARCIS (Netherlands)

    Roijakkers, A.H.W.M.; Hagedoorn, J.; Kranenburg, van H.

    2005-01-01

    This paper analyses the role of repeated ties in the high-tech pharmaceutical biotechnology industry, a sector that is characterized by a strong dual market structure. Our most important finding is that previous ties in pairs of large pharmaceutical companies and small biotechnology firms have a

  6. Weak Ties and Self-Regulation in Job Search: The Effects of Goal Orientation on Networking

    Science.gov (United States)

    Hatala, John-Paul; Yamkovenko, Bogdan

    2016-01-01

    The purpose of this study is to empirically investigate the relationship between the self-regulatory variable of goal orientation and the extent to which job seekers reach out to and use weak ties in their job search. Weak ties, as defined by Granovettor, are connections to densely knit networks outside the individual's direct contacts who could…

  7. Finite element analyses of continuous filament ties for masonry applications: final report for the Arquin Corporation

    Energy Technology Data Exchange (ETDEWEB)

    Quinones, Sr., Armando [Arquin Corporation, La Luz, NM (United States); Bibeau, Tiffany A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Ho, Clifford Kuofei

    2006-06-01

    Finite-element analyses were performed to simulate the response of a hypothetical masonry shear wall with and without continuous filament ties to various lateral loads. The loads represented three different scenarios: (1) 100 mph wind, (2) explosive attack, and (3) an earthquake. In addition, a static loading analysis and cost comparison were performed to evaluate optimal materials and designs for the spacers affixed to the filaments. Results showed that polypropylene, ABS, and polyethylene (high density) were suitable materials for the spacers based on performance and cost, and the short T-spacer design was optimal based on its performance and functionality. Results of the shear-wall loading simulations revealed that simulated walls with the continuous filament ties yielded factors of safety that were at least ten times greater than those without the ties. In the explosive attack simulation (100 psi), the simulated wall without the ties failed (minimum factor of safety was less than one), but the simulated wall with the ties yielded a minimum factor of safety greater than one. Simulations of the walls subject to lateral loads caused by 100 mph winds (0.2 psi) and seismic events with a peak ground acceleration of 1 ''g'' (0.66 psi) yielded no failures with or without the ties. Simulations of wall displacement during the seismic scenarios showed that the wall with the ties resulted in a maximum displacement that was 20% less than the wall without the ties.

  8. Predicting Bed Mobility in a Simple River Channel

    Science.gov (United States)

    Wydzga, M. A.; Legleiter, C.; Dunne, T.

    2007-12-01

    Prediction of the frequency and spatial pattern of bed mobility in gravel bed rivers is central to a wide range of theoretical and applied interests ranging from sediment transport to the impacts of natural or managed floods on aquatic organisms. Although bed mobility has been investigated in numerous flume and field studies, accurate predictions of grain entrainment and transport in gravel bed rivers remain elusive. Alluvial rivers typically encompass a much wider range of hydraulic and sedimentological conditions than those that have been recreated in laboratory flume studies upon which many grain entrainment and transport models are based. These flume studies are limited to the examination of processes occurring over the short term, commonly with the absence of slower processes such as fine-grain infilling. On the other hand, in field studies key variables can not be controlled and the spatial complexity of processes and conditions complicate data collection and analysis. A unique opportunity currently exists to help bridge this gap between laboratory and field studies: a 3.2 km long, recently constructed, single thread, alternate bar, gravel bed river channel of the Merced River. This channel, constructed for ecosystem restoration purposes, is slowly developing greater complexity, but is still currently defined by a simple plan form and cross-sectional channel geometry compared to most natural gravel bed river channels. This channel can thus be considered a full-scale flume. In the six years since the channel was constructed, a wider range of sedimentological bed conditions have evolved than have been created in a laboratory flume. We are characterizing the bed grain sizes, flow field, grain entrainment, and the sedimentological or bed state conditions in this simple channel. The flow field is modeled using a calibrated, 2D hydrodynamic flow model, MD_SWMS. Grain entrainment is measured with both metal tags inserted into the bed, and painted rock tracers

  9. Social support and social interaction ties on internet addiction: integrating online and offline contexts.

    Science.gov (United States)

    Wang, Edward Shih-Tse; Wang, Michael Chih-Hung

    2013-11-01

    This study explores the relationship between social support and social interaction ties on Internet addiction by integrating both online and offline social encounters. A total of 1,642 members of online social communities participated in this research, for which structural equation modeling was used for analysis. The findings show that social support is positively associated with social interaction ties in both online and offline contexts. In addition, online social support and online social interaction ties are positively associated with Internet addiction, whereas offline social support and social interaction ties on Internet addiction are negatively associated. This finding has important implications not only for understanding the cause of Internet addiction but also for understanding the diminishing Internet addiction due to social support and social interaction ties.

  10. The emotional responses of browsing Facebook: Happiness, envy, and the role of tie strength.

    Science.gov (United States)

    Lin, Ruoyun; Utz, Sonja

    2015-11-01

    On Facebook, users are exposed to posts from both strong and weak ties. Even though several studies have examined the emotional consequences of using Facebook, less attention has been paid to the role of tie strength. This paper aims to explore the emotional outcomes of reading a post on Facebook and examine the role of tie strength in predicting happiness and envy. Two studies - one correlational, based on a sample of 207 American participants and the other experimental, based on a sample of 194 German participants - were conducted in 2014. In Study 2, envy was further distinguished into benign and malicious envy. Based on a multi-method approach, the results showed that positive emotions are more prevalent than negative emotions while browsing Facebook. Moreover, tie strength is positively associated with the feeling of happiness and benign envy, whereas malicious envy is independent of tie strength after reading a (positive) post on Facebook.

  11. Influence of ties on the behavior of short reinforced concrete columns strengthened by external CFRP

    Directory of Open Access Journals (Sweden)

    Sarsam Kaiss

    2018-01-01

    Full Text Available An experimental study was carried out to investigate the behavior of normal strength reinforce concret (RC circular short column strengthned with “carbon fiber reinforced polymer (CFRP sheets”. Three series comprising totally of (15 specimens loaded until failure under concentric compresion load. Strengthening was varied by changing the number of CFRP strips, spacing and wrapping methods. The findings of this research can be summarized as follows: for the columns without CFRP, the influence of the tie spacing was significant: compared with 130 mm tie spacing, dropping the spacing to 100 mm and 70 mm increased the load carrying capacity by 18% and 26%, respectively. The columns with less internal confinement (lesser amount of ties were strengthened more significantly by the CFRP than the ones with greater amount of internal ties. As an example of the varying effectiveness of the fully wrapped CFRP, the column with ties at 130 mm was strengthened by 90% with the CFRP. In contrast, the ones with 70 mm spaced ties only increased in strength with CFRP by 66%. Compared with the control specimen (no CFRP, the same amount of CFRP when used as hoop strips led to more strengthening than using CFRP as a spiral strip- the former led to nearly 9% more strengthening than the latter in the case of 130 mm spaced internal steel ties. In the case of 100 mm internal steel ties, the difference (between the hoops & spiral CFRP strengthening is close to 4%. In contrast, there is no difference between the two methods of strengthening in the heavily tied columns (70 mm tied spacing.

  12. Strut elaboration in strut-and-tie model

    Directory of Open Access Journals (Sweden)

    Mohammad PANJEHPOUR

    2012-12-01

    Full Text Available The Strut-and-Tie Model (STM has been incorporated into the codes and standards because of its consistency and rationality since last decade. However, it has encountered few challenges whilst its implementation. The effective compressive strength of strut has been a complex issue among researchers since emergence of STM. This review serves as a base for future developments of STM. It addresses several ways towards enhancing our understanding of strut performance in the STM. It also throws up questions for further investigation of effective compressive strength of strut in the STM. This review is confined to the evaluation of strut effectiveness factor based on the available codes and standards particularly AASHTO LRFD and ACI 318-08. According to the example given in this paper, there is sometimes a marked difference of approximately 50% between strut effectiveness factor recommended by AASHTO LRFD and ACI 318-08. More broadly, research is needed to determine which of the complicated strut effectiveness factor recommended by AASHTO LRFD and the simple one recommended by ACI 318-08 is optimum.

  13. Ties that bind: revisiting context, identity, and attitudes

    Directory of Open Access Journals (Sweden)

    James S. Krueger

    2015-07-01

    Full Text Available The article focuses on group-based features of issue publics and advances the concept of residual group saliency as a way to organize members of issue publics. We accord veterans exemplar or prototype status, and civilians as periphery members of this issue public. As issue public exemplars, veterans anchor the “right” attitudes and behaviors for the veteran issue public, and civilians, especially those with family ties to veterans, gravitate toward those exemplar attitudes. We argue that pressure to conform to these “right” attitudes among civilians who are connected to a veteran is greater when there are more veterans in their environment. However, veterans and civilians who are not connected to a veteran are not responsive to such contextual effects, the former because they are already exemplars, and the latter because there is no motivation to evaluate the self in relation to veterans. We test and find support for these claims using data from the 2010 Cooperative Congressional Election Study. We conclude with an evaluative discussion and suggestions for future research.

  14. Tying dark matter to baryons with self-interactions.

    Science.gov (United States)

    Kaplinghat, Manoj; Keeley, Ryan E; Linden, Tim; Yu, Hai-Bo

    2014-07-11

    Self-interacting dark matter (SIDM) models have been proposed to solve the small-scale issues with the collisionless cold dark matter paradigm. We derive equilibrium solutions in these SIDM models for the dark matter halo density profile including the gravitational potential of both baryons and dark matter. Self-interactions drive dark matter to be isothermal and this ties the core sizes and shapes of dark matter halos to the spatial distribution of the stars, a radical departure from previous expectations and from cold dark matter predictions. Compared to predictions of SIDM-only simulations, the core sizes are smaller and the core densities are higher, with the largest effects in baryon-dominated galaxies. As an example, we find a core size around 0.3 kpc for dark matter in the Milky Way, more than an order of magnitude smaller than the core size from SIDM-only simulations, which has important implications for indirect searches of SIDM candidates.

  15. Tie Points Extraction for SAR Images Based on Differential Constraints

    Science.gov (United States)

    Xiong, X.; Jin, G.; Xu, Q.; Zhang, H.

    2018-04-01

    Automatically extracting tie points (TPs) on large-size synthetic aperture radar (SAR) images is still challenging because the efficiency and correct ratio of the image matching need to be improved. This paper proposes an automatic TPs extraction method based on differential constraints for large-size SAR images obtained from approximately parallel tracks, between which the relative geometric distortions are small in azimuth direction and large in range direction. Image pyramids are built firstly, and then corresponding layers of pyramids are matched from the top to the bottom. In the process, the similarity is measured by the normalized cross correlation (NCC) algorithm, which is calculated from a rectangular window with the long side parallel to the azimuth direction. False matches are removed by the differential constrained random sample consensus (DC-RANSAC) algorithm, which appends strong constraints in azimuth direction and weak constraints in range direction. Matching points in the lower pyramid images are predicted with the local bilinear transformation model in range direction. Experiments performed on ENVISAT ASAR and Chinese airborne SAR images validated the efficiency, correct ratio and accuracy of the proposed method.

  16. TIE POINTS EXTRACTION FOR SAR IMAGES BASED ON DIFFERENTIAL CONSTRAINTS

    Directory of Open Access Journals (Sweden)

    X. Xiong

    2018-04-01

    Full Text Available Automatically extracting tie points (TPs on large-size synthetic aperture radar (SAR images is still challenging because the efficiency and correct ratio of the image matching need to be improved. This paper proposes an automatic TPs extraction method based on differential constraints for large-size SAR images obtained from approximately parallel tracks, between which the relative geometric distortions are small in azimuth direction and large in range direction. Image pyramids are built firstly, and then corresponding layers of pyramids are matched from the top to the bottom. In the process, the similarity is measured by the normalized cross correlation (NCC algorithm, which is calculated from a rectangular window with the long side parallel to the azimuth direction. False matches are removed by the differential constrained random sample consensus (DC-RANSAC algorithm, which appends strong constraints in azimuth direction and weak constraints in range direction. Matching points in the lower pyramid images are predicted with the local bilinear transformation model in range direction. Experiments performed on ENVISAT ASAR and Chinese airborne SAR images validated the efficiency, correct ratio and accuracy of the proposed method.

  17. Transnational Corporate Ties: A Synopsis of Theories and Empirical Findings

    Directory of Open Access Journals (Sweden)

    Michael Nollert

    2015-08-01

    Full Text Available In general, corporations are not isolated actors in an economic “war of all against all” but members of corporate networks of global reach. Although the literature on globalization emphasizes the increasing economic power of these networks and postulates the formation of a transnational capitalist class, there is still a lack of empirical findings. The article starts with a review of theoretical perspectives (resource dependence, social capital, coordination of markets, financial hegemony, class hegemony, inner circle, and transnational capitalist class which focuses on the functions and structures of corporate interlocks at the national and the transnational level. The subsequent section offers an outline of empirical studies concerning transnational corporate networks. These analyses of corporate ties (interlocking directorates, financial participations and policy group affiliations suggest the emergence of transnational economic elites whose members, however, have not lost their national identity. In the final section, the theoretical perspectives will be assessed and some prospects are sketched out. Finally, it will be argued that the disintegration of the world society, which is considerably driven by rent-seeking corporate networks, can only be restrained if a potential global regulatory agency will be anchored in a post-Washington consensus.

  18. Dzimuma stereotipizācija tiešsaistes laikrakstos

    OpenAIRE

    Tirzīte, Asne

    2015-01-01

    Pētnieciskā darba mērķis ir atrast un analizēt stereotipus britu tiešsaites avīžu The Guardian un Daily Mail rakstos par biznesu, lai uzzinātu no kādiem valodas elementiem sastāv stereotipu atspoguļojums un kā mediju diskursā tiek atspoguļotas dzimuma un profesionālās identitātes. Darba teorētiskā daļa apskata pašreizējā pētījuma metodi un iepriekšējo pētnieku darbus par šo tēmu. Izmantotā kvalitatīvā pētījuma metode ir Normana Fērklova (1992) trīsdimensionālais kritiskās diskursa analīzes mo...

  19. Can space ties on board GNSS satellites replace terrestrial ties in the implementation of Terrestrial Reference Frames?

    Science.gov (United States)

    Bruni, Sara; Zerbini, Susanna; Altamimi, Zuheir; Rebischung, Paul; Errico, Maddalena; Santi, Efisio

    2016-04-01

    SLR techniques via the so-called space ties, instead of relying on the terrestrial ties evaluated with ground measurement campaigns at co-located ITRF sites.

  20. Recovery From Radiation-induced Bone Marrow Damage by HSP25 Through Tie2 Signaling

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hae-June [Division of Radiation Effects, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Kwon, Hee-Chung [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Chung, Hee-Yong [College of Medicine, Hanyang University, Seoul (Korea, Republic of); Lee, Yoon-Jin [Division of Radiation Effects, Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Lee, Yun-Sil, E-mail: yslee0425@ewha.ac.kr [College of Pharmacy and Division of Life and Pharmaceutical Sciences, Ewha Woman' s University, Seoul (Korea, Republic of)

    2012-09-01

    Purpose: Whole-body radiation therapy can cause severe injury to the hematopoietic system, and therefore it is necessary to identify a novel strategy for overcoming this injury. Methods and Materials: Mice were irradiated with 4.5 Gy after heat shock protein 25 (HSP25) gene transfer using an adenoviral vector. Then, peripheral blood cell counts, histopathological analysis, and Western blotting on bone marrow (BM) cells were performed. The interaction of HSP25 with Tie2 was investigated with mouse OP9 and human BM-derived mesenchymal stem cells to determine the mechanism of HSP25 in the hematopoietic system. Results: HSP25 transfer increased BM regeneration and reduced apoptosis following whole-body exposure to ionizing radiation (IR). The decrease in Tie2 protein expression that followed irradiation of the BM was blocked by HSP25 transfer, and Tie2-positive cells were more abundant among the BM cells of HSP25-transferred mice, even after IR exposure. Following systemic RNA interference of Tie2 before IR, HSP25-mediated radioprotective effects were partially blocked in both mice and cell line systems. Stability of Tie2 was increased by HSP25, a response mediated by the interaction of HSP25 with Tie2. IR-induced tyrosine phosphorylation of Tie2 was augmented by HSP25 overexpression; downstream events in the Tie2 signaling pathway, including phosphorylation of AKT and EKR1/2, were also activated. Conclusions: HSP25 protects against radiation-induced BM damage by interacting with and stabilizing Tie2. This may be a novel strategy for HSP25-mediated radioprotection in BM.

  1. Resilience by solidary ties (Resiliencia por lazos de solidaridad

    Directory of Open Access Journals (Sweden)

    Antonio Alaminos

    2015-07-01

    Full Text Available This article considers an empirical approach to the relationships among three well known concepts: “Benevolence” (Schwartz, Solidarity and Resilience ("Subjective wellbeing scale" - SWB. The first concept refers to cultural values, the second one to social networks and the third to the ability to recover from crisis. The measurement of solidarity has been done from the point of view of supportive ties. The baseline hypothesis considers that the presence of a high value in Benevolence contributes to the involvements in solidarity networks. Participation in supportive relationships facilitates recovery from personal crisis. Using data from the European Social Survey (ESS6, we conclude from this structural analysis that the resilience reflected in a society is partly a consequence of the supportive networks shaped by the presence of benevolence values. | Tras introducir teóricamente los conceptos de "Benevolencia" (Schwartz, "Lazos de solidaridad" y "Resiliencia", se presenta su operativización en la Encuesta Social Europea de 2012. La hipótesis de partida plantea que la presencia de un valor alto en Benevolencia influye en la participación en interacciones solidarias y que la participación en redes solidarias facilita el recobrarse de las crisis. A partir de estos datos, y considerando varias sociedades europeas, se han testado dos modelos alternativos, según el efecto de la Benevolencia y los lazos de solidaridad sobre la resiliencia. Se concluye que existe un efecto directo de los valores de Benevolencia sobre la Solidaridad, y de esta sobre la Resiliencia. La influencia de los valores de Benevolencia sobre la Resiliencia se establece de forma indirecta mediante la activación de relaciones solidarias.

  2. IVF, same-sex couples and the value of biological ties

    DEFF Research Database (Denmark)

    Di Nucci, Ezio

    2016-01-01

    Ought parents, in general, to value being biologically tied to their children? Is it important, in particular, that both parents be biologically tied to their children? I will address these fundamental questions by looking at a fairly new practice within IVF treatments, so-called IVF......-with-ROPA (Reception of Oocytes from Partner), which allows lesbian couples to 'share motherhood', with one partner providing the eggs while the other becomes pregnant. I believe that IVF-with-ROPA is, just like other IVF treatments, morally permissible, but here I argue that the increased biological ties which IVF...

  3. Hanging Together, Together Hung? Career Implications of Interpersonal Ties Between CEOs and Top Managers

    Directory of Open Access Journals (Sweden)

    Stefan Hilger

    2013-05-01

    Full Text Available Is it good or bad for senior executives to have strong interpersonal ties to the CEO? We argue that a strong relationship with the CEO raises the likelihood that a top manager stays in office or makes an upward career move when the CEO leaves office voluntarily. At the same time, such interpersonal ties also reinforce the negative spillover effects of a dismissal of the CEO on the career prospects of the manager concerned. Our empirical analysis lends support to both arguments. We contribute to managerial succession research by underlining the ambivalence of interpersonal ties within top management teams.

  4. Square and bow-tie configurations in the cyclic evasion problem

    Science.gov (United States)

    Arnold, M. D.; Golich, M.; Grim, A.; Vargas, L.; Zharnitsky, V.

    2017-05-01

    Cyclic evasion of four agents on the plane is considered. There are two stationary shapes of configurations: square and degenerate bow-tie. The bow-tie is asymptotically attracting while the square is of focus-center type. Normal form analysis shows that square is nonlinearly unstable. The stable manifold consists of parallelograms that all converge to the square configuration. Based on these observations and numerical simulations, it is conjectured that any non-parallelogram non-degenerate configuration converges to the bow-tie.

  5. 78 FR 57619 - Prestressed Concrete Steel Rail Tie Wire From Mexico, Thailand, and the People's Republic of...

    Science.gov (United States)

    2013-09-19

    ...] Prestressed Concrete Steel Rail Tie Wire From Mexico, Thailand, and the People's Republic of China... prestressed concrete steel rail tie wire from Mexico, Thailand, and the People's Republic of China. See Prestressed Concrete Steel Rail Tie Wire From Mexico, the People's Republic of China, and Thailand: Initiation...

  6. Moving with the Military: Race, Class, and Gender Differences in the Employment Consequences of Tied Migration

    National Research Council Canada - National Science Library

    Cooney, Richard

    2003-01-01

    .... Previous research demonstrates negative employment and earnings consequences for tied migrants, but little is known about how the impact of such mobility differs by the gender, race, and class of the trailing spouse. The U.S...

  7. The effects of emitter-tied field plates on lateral PNP ionizing radiation response

    International Nuclear Information System (INIS)

    Barnaby, H.J.; Schrimpf, R.D.; Cirba, C.R.; Pease, R.L.; Fleetwood, D.M.; Kosier, S.L.

    1998-03-01

    Radiation response comparisons of lateral PNP bipolar technologies reveal that device hardening may be achieved by extending the emitter contact over the active base. The emitter-tied field plate suppresses recombination of carriers with interface traps

  8. Group formation in a public good experiment: on the dynamics of social ties structures

    NARCIS (Netherlands)

    Sonnemans, J.H.; van Dijk, F.; van Winden, F.A.A.M.

    1999-01-01

    Economic behavior often takes place in groups of small numbers of peopleinteracting with each other (like work teams, neighborhoods, socialnetworks, etc.). Characteristic of such interaction is the development of(affective) interpersonal relationships, or social ties. According tosociologists, the

  9. ParTIES: a toolbox for Paramecium interspersed DNA elimination studies.

    Science.gov (United States)

    Denby Wilkes, Cyril; Arnaiz, Olivier; Sperling, Linda

    2016-02-15

    Developmental DNA elimination occurs in a wide variety of multicellular organisms, but ciliates are the only single-celled eukaryotes in which this phenomenon has been reported. Despite considerable interest in ciliates as models for DNA elimination, no standard methods for identification and characterization of the eliminated sequences are currently available. We present the Paramecium Toolbox for Interspersed DNA Elimination Studies (ParTIES), designed for Paramecium species, that (i) identifies eliminated sequences, (ii) measures their presence in a sequencing sample and (iii) detects rare elimination polymorphisms. ParTIES is multi-threaded Perl software available at https://github.com/oarnaiz/ParTIES. ParTIES is distributed under the GNU General Public Licence v3. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  10. One long tie bar broken after 3 days because of hydrogen contamination.

    CERN Multimedia

    H. Gerwig

    2000-01-01

    The tie bars have been produced with a high yield strength. As known for these type of high strength bolts, and hydrogen contamination during manufacture or heat treatment could lead to rupture under stress after several days.

  11. Neural dynamics of social tie formation in economic decision-making

    NARCIS (Netherlands)

    Bault, N.; Pelloux, B.; Fahrenfort, J.J.; Ridderinkhof, K.R.; van Winden, F.

    2015-01-01

    The disposition for prosocial conduct, which contributes to cooperation as arising during social interaction, requires cortical network dynamics responsive to the development of social ties, or care about the interests of specific interaction partners. Here, we formulate a dynamic computational

  12. Multi-area economic dispatch with tie-line constraints employing ...

    African Journals Online (AJOL)

    user

    The economic dispatch problem is frequently solved without considering ... programming algorithm was proposed for the MAED solution with tie-line constraints ..... are the difference between two randomly chosen parameter vectors, a concept.

  13. Do Social Ties Affect Our Health? Exploring the Biology of Relationships

    Science.gov (United States)

    ... Do Social Ties Affect Our Health? Exploring the Biology of Relationships En español Send us your comments ... neighbors, or others, social connections can influence our biology and well-being. Wide-ranging research suggests that ...

  14. Fiber Optic Tamper Indicating Enclosure (TIE); A Case Study in Authentication

    Energy Technology Data Exchange (ETDEWEB)

    Anheier, Norman C.; Benz, Jacob M.; Tanner, Jennifer E.; Westman, Matthew P.

    2015-07-15

    A robust fiber optic-based tamper-indicating enclosure (TIE) has been developed by PNNL through funding by the National Nuclear Security Administration Office of Nuclear Verification over the past few years. The objective of this work is to allow monitors to have confidence in both the authenticity and integrity of the TIE and the monitoring equipment inside, throughout the time it may be located at a host facility. Incorporating authentication features into the design were the focus of fiscal year 2014 development efforts. Throughout the development process, modifications have been made to the physical TIE design based on lessons learned via exercises and expert elicitation. The end result is a robust and passive TIE which can be utilized to protect monitoring party equipment left in a host facility.

  15. Ties that bind: multiple relationships between clinical researchers and the pharmaceutical industry.

    Science.gov (United States)

    Henry, David; Doran, Evan; Kerridge, Ian; Hill, Suzanne; McNeill, Paul M; Day, Richard

    2005-11-28

    It is believed that pharmaceutical industry sponsorship of clinical research leads to the development of multiple ties between clinicians and the pharmaceutical industry. To quantify this relationship we conducted a survey of medical specialists listed in the Medical Directory of Australia in 2002 and 2003. A questionnaire was mailed that elicited information about all aspects of research relationships between clinicians and pharmaceutical companies. The odds of reporting multiple additional ties (financial and professional) with pharmaceutical companies by clinicians who had an active research relationship were compared with those who did not. All clinicians who returned a completed questionnaire about their research activities were included in the study. A questionnaire was mailed to 2120 medical specialists; 823 (39%) responded. Of these, 338 (41%) reported involvement in industry-sponsored research in the previous year. They were more likely than others to have been offered industry-sponsored items or activities valued at more than 500 AU dollars (>382 US dollars; odds ratio [OR], 3.5; 95% confidence interval [CI], 2.6-4.7) and support for attending international conferences (OR, 5.4; 95% CI, 3.9-7.4). The strongest associations were seen for acting as a paid consultant to industry (OR, 9.0; 95% CI, 3.9-20.4) and for membership on advisory boards (OR, 6.9; 95% CI, 5.1-9.6). There was a strong relationship between research collaboration and accumulation of industry ties. For 1 additional tie the OR was 2.2 (95% CI, 1.2-3.8) and rose to 6.3 (95% CI, 3.5-11.1) with 3 ties and 41.8 (95% CI, 14.5-143.4) with 6 or more ties. Medical specialists who have research relationships with the pharmaceutical industry are much more likely to have multiple additional ties than those who do not have research relationships. Institutional review should discourage clinical researchers from developing multiple ties.

  16. Reducing Electromagnetic Interference in a Grid Tied Single Phase Power Inverter

    Science.gov (United States)

    2016-09-01

    With the growing demand for a reliable electrical grid, backup power supplies and energy management systems are a necessity. Systems such as server...ELECTROMAGNETIC INTERFERENCE IN A GRID TIED SINGLE PHASE POWER INVERTER by Jason Hassan Valiani September 2016 Thesis Advisor: Giovanna Oriti...3. REPORT TYPE AND DATES COVERED Master’s thesis 4. TITLE AND SUBTITLE REDUCING ELECTROMAGNETIC INTERFERENCE IN A GRID TIED SINGLE PHASE POWER

  17. Division of tongue tie: review of practice through a tertiary paediatric otorhinolaryngology service.

    LENUS (Irish Health Repository)

    Glynn, R W

    2012-10-01

    Recent NICE guidance declared that evidence regarding surgical division of tongue tie was adequate to support the use of the procedure, provided that normal arrangements are in place for consent, audit and clinical governance. This work aimed to carry out a retrospective review of those patients who have previously undergone tongue tie division through a tertiary paediatric otorhinolaryngology service. We further aimed to identify the referral patterns, indications for, and outcomes following, division.

  18. Identification of proangiogenic TIE2-expressing monocytes (TEMs) in human peripheral blood and cancer

    OpenAIRE

    Venneri, Mary Anna; De Palma, Michele; Ponzoni, Maurilio; Pucci, Ferdinando; Scielzo, Cristina; Zonari, Erika; Mazzieri, Roberta; Doglioni, Claudio; Naldini, Luigi

    2007-01-01

    Tumor-infiltrating myeloid cells, including tumor-associated macrophages (TAMs), have been implicated in tumor progression. We recently described a lineage of mouse monocytes characterized by expression of the Tie2 angiopoietin receptor and required for the vascularization and growth of several tumor models. Here, we report that TIE2 expression in human blood identifies a subset of monocytes distinct from classical inflammatory monocytes and comprised within the less abundant "resident" popul...

  19. Evaluation of Shear Tie Connectors for Use in Insulated Concrete Sandwich Panels

    Science.gov (United States)

    2009-12-01

    stainless steel, galvanized carbon steel, carbon fiber reinforced polymers (CFRP), glass fiber reinforced polymer (GFRP), and basalt fiber reinforced polymer...Glass Fiber Reinforced Polymer (GFRP) Delta Tie produced by Dayton Superior; • (B) THERMOMASS® composite GFRP pins; • (C) THERMOMASS® non-composite...GFRP pins; • (D) Altus Group CFRP Grid; • (E) Universal Building products GFRP Teplo Tie; and • (F) Universal Building products Basalt FRP

  20. Citizens and service channels: channel choice and channel management implications

    NARCIS (Netherlands)

    Pieterson, Willem Jan

    2010-01-01

    The arrival of electronic channels in the 1990s has had a huge impact on governmental service delivery. The new channels have led to many new opportunities to improve public service delivery, not only in terms of citizen satisfaction, but also in cost reduction for governmental agencies. However,

  1. Ipsilateral deficits in 1-handed shoe tying after left or right hemisphere stroke.

    Science.gov (United States)

    Poole, Janet L; Sadek, Joseph; Haaland, Kathleen Y

    2009-10-01

    Poole JL, Sadek J, Haaland KY. Ipsilateral deficits in 1-handed shoe tying after left or right hemisphere stroke. To examine 1-handed shoe tying performance and whether cognitive deficits more associated with left or right hemisphere damage differentially affect it after unilateral stroke. Observational cohort comparing ipsilesional shoe tying, spatial and language skills, and limb praxis. Primary care Veterans Affairs and private medical center. Not applicable. Volunteer right-handed sample of adults with left or right hemisphere damage and healthy demographically matched adults. The number of correct trials and the total time to complete 10 trials tying a shoe using the 1-handed method. Both stroke groups had fewer correct trials and were significantly slower tying the shoe than the control group. Spatial skills predicted accuracy and speed after right hemisphere damage. After left hemisphere damage, accuracy was predicted by spatial skills and limb praxis, while speed was predicted by limb praxis only. Ipsilesional shoe tying is similarly impaired after left or right hemisphere damage, but for different reasons. Spatial deficits had a greater influence after right hemisphere damage, and limb apraxia had a greater influence after left hemisphere damage. Language deficits did not affect performance, indicating that aphasia does not preclude using this therapy approach. These results suggest that rehabilitation professionals should consider assessment of limb apraxia and ipsilesional skill training in the performance of everyday tasks.

  2. Mobile devices and weak ties: a study of vision impairments and workplace access in Bangalore.

    Science.gov (United States)

    Pal, Joyojeet; Lakshmanan, Meera

    2015-07-01

    To explore ways in which social and economic interactions are changed by access to mobile telephony. This is a mixed-methods study of mobile phone use among 52 urban professionals with vision impairments in Bangalore, India. Interviews and survey results indicated that mobile devices, specifically those with adaptive technology software, play a vital role as multi-purpose devices that enable people with disabilities to navigate economically and socially in an environment where accessibility remains a significant challenge. We found that mobile devices play a central role in enabling and sustaining weak ties, but also that these weak ties have important gender-specific implications. We found that women have less access to weak ties than men, which impacts women's access to assistive technology (AT). This has potential implications for women's sense of safety and independence, both of which are strongly related to AT access. Implications for Rehabilitation Adaptive technologies increase individuals' ability to keep in contact with casual connections or weak ties through phone calls or social media. Men tend to have stronger access to weak ties than women in India due to cultural impediments to independent access to public spaces. Weak ties are an important source of assistive technology (AT) due to the high rate of resale of used AT, typically through informal networks.

  3. Relationships between authorship contributions and authors' industry financial ties among oncology clinical trials.

    Science.gov (United States)

    Rose, Susannah L; Krzyzanowska, Monika K; Joffe, Steven

    2010-03-10

    PURPOSE To test the hypothesis that authors who play key scientific roles in oncology clinical trials, and who therefore have increased influence over the design, analysis, interpretation or reporting of trials, are more likely than those who do not play such roles to have financial ties to industry. METHODS Data were abstracted from all trials (n = 235) of drugs or biologic agents published in the Journal of Clinical Oncology between January 1, 2006 and June 30, 2007. Article-level data included sponsorship, age group (adult v pediatric), phase, single versus multicenter, country (United States v other), and number of authors. Author-level data (n = 2,927) included financial ties (eg, employment, consulting) and performance of key scientific roles (ie, conception/design, analysis/interpretation, or manuscript writing). Associations between performance of key roles and financial ties, adjusting for article-level covariates, were examined using generalized linear mixed models. Results One thousand eight hundred eighty-one authors (64%) reported performing at least one key role, and 842 authors (29%) reported at least one financial tie. Authors who reported performing a key role were more likely than other authors to report financial ties to industry (adjusted odds ratio [OR], 4.3; 99% CI, 3.0 to 6.0; P analysis, and interpretation, or reporting of oncology clinical trials are more likely than authors who do not perform such roles to have financial ties to industry.

  4. [Medical equipment companies and their ties with technology development centers in Mexico].

    Science.gov (United States)

    Hernández, B; Arredondo, A; Cruz, C; Sánchez, E; Damián, T

    1993-10-01

    The purpose of this study was to determine the characteristics of the companies that produce, distribute, and service medical equipment in Mexico and the factors related to whether or not they had established ties with research and technology development centers. The data analyzed came from a survey of such companies carried out in Mexico City and environs in 1989. The information was updated in 1991. Multivariate analyses were carried out in order to identify the characteristics of companies that had established ties or wished to do so and the areas of interest of those companies. Of 208 companies surveyed, only 23% had ties with research centers. The companies that had such ties or were interested in establishing them tended to invest in research and to have made plans for expansion. The establishment of ties appeared to be a two-way process, with positive consequences for the companies involved, the research centers, and the health sector. It was concluded that it would be advantageous to design programs to promote ties with companies having the characteristics mentioned.

  5. Multipronged regulatory functions of a novel endonuclease (TieA) from Helicobacter pylori.

    Science.gov (United States)

    Devi, Savita; Ansari, Suhail A; Tenguria, Shivendra; Kumar, Naveen; Ahmed, Niyaz

    2016-11-02

    Helicobacter pylori portrays a classical paradigm of persistent bacterial infections. A well balanced homeostasis of bacterial effector functions and host responses is purported to be the key in achieving long term colonization in specific hosts. H. pylori nucleases have been shown to assist in natural transformation, but their role in virulence and colonization remains elusive. Therefore, it is imperative to understand the involvement of these nucleases in the pathogenesis of H. pylori Here, we report the multifaceted role of a TNFR-1 interacting endonuclease A (TieA) from H. pylori. tieA expression is differentially regulated in response to environmental stress and post adherence to gastric epithelial cells. Studies with isogenic knockouts of tieA revealed it to be a secretory protein which translocates into the host gastric epithelial cells independent of a type IV secretion system, gets phosphorylated by DNA-PK kinase and auto-phosphorylates as serine kinase. Furthermore, TieA binds to and cleaves DNA in a non-specific manner and promotes Fas mediated apoptosis in AGS cells. Additionally, TieA induced pro-inflammatory cytokine secretion via activation of transcription factor AP-1 and signaled through MAP kinase pathway. Collectively, TieA with its multipronged and moonlighting functions could facilitate H. pylori in maintaining a balance of bacterial adaptation, and elimination by the host responses. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

  6. [Construction of recombinant lentiviral vector of Tie2-RNAi and its influence on malignant melanoma cells in vitro].

    Science.gov (United States)

    Shan, Xiu-ying; Liu, Zhao-liang; Wang, Biao; Guo, Guo-xiang; Wang, Mei-shui; Zhuang, Fu-lian; Cai, Chuan-shu; Zhang, Ming-feng; Zhang, Yan-ding

    2011-07-01

    To construct lentivector carrying Tie2-Small interfering RNA (SiRNA), so as to study its influence on malignant melanoma cells. Recombinant plasmid pSilencer 1.0-U6-Tie2-siRNA and plasmid pNL-EGFP were digested with XbaI, ligated a target lentiviral transfer plasmid of pNL-EGFP-U6-Tie2-I or pNL-EGFP-U6-Tie2-II, and then the electrophoresis clones was sequenced. Plasmids of pNL-EGFP-U6-Tie2-I and pNL-EGFP-U6-Tie2-II were constructed and combined with pVSVG and pHelper, respectively, to constitute lentiviral vector system of three plasmids. The Lentiviral vector system was transfected into 293T cell to produce pNL-EGFP-U6-Tie2- I and pNL-EGFP-U6-Tie2-II lentivirus. Then the supernatant was collected to determine the titer. Malignant melanoma cells were infected by both lentiviruses and identified by Realtime RT-PCR to assess inhibitory efficiency. The recombinant lentiviral vectors of Tie2-RNAi were constructed successfully which were analyzed with restriction enzyme digestion and identified by sequencing. And the titer of lentiviral vector was 8.8 x 10(3)/ml, which was determined by 293T cell. The results of Realtime RT-PCR demonstrated that the lentiviral vectors of Tie2-RNAi could infect malignant melanoma cells and inhibit the expression of Tie2 genes in malignant melanoma cells (P0.05) between the two lentiviral vectors of Tie2-RNAi. Lentivector carrying Tie2-SiRNA can be constructed successfully and inhibit the expression of Tie2 gene in vitro significantly. The study will supply the theory basis for the further research on the inhibition of tumor growth in vivo.

  7. Financial ties of principal investigators and randomized controlled trial outcomes: cross sectional study.

    Science.gov (United States)

    Ahn, Rosa; Woodbridge, Alexandra; Abraham, Ann; Saba, Susan; Korenstein, Deborah; Madden, Erin; Boscardin, W John; Keyhani, Salomeh

    2017-01-17

     To examine the association between the presence of individual principal investigators' financial ties to the manufacturer of the study drug and the trial's outcomes after accounting for source of research funding.  Cross sectional study of randomized controlled trials (RCTs).  Studies published in "core clinical" journals, as identified by Medline, between 1 January 2013 and 31 December 2013.  Random sample of RCTs focused on drug efficacy.  Association between financial ties of principal investigators and study outcome.  A total of 190 papers describing 195 studies met inclusion criteria. Financial ties between principal investigators and the pharmaceutical industry were present in 132 (67.7%) studies. Of 397 principal investigators, 231 (58%) had financial ties and 166 (42%) did not. Of all principal investigators, 156 (39%) reported advisor/consultancy payments, 81 (20%) reported speakers' fees, 81 (20%) reported unspecified financial ties, 52 (13%) reported honorariums, 52 (13%) reported employee relationships, 52 (13%) reported travel fees, 41 (10%) reported stock ownership, and 20 (5%) reported having a patent related to the study drug. The prevalence of financial ties of principal investigators was 76% (103/136) among positive studies and 49% (29/59) among negative studies. In unadjusted analyses, the presence of a financial tie was associated with a positive study outcome (odds ratio 3.23, 95% confidence interval 1.7 to 6.1). In the primary multivariate analysis, a financial tie was significantly associated with positive RCT outcome after adjustment for the study funding source (odds ratio 3.57 (1.7 to 7.7). The secondary analysis controlled for additional RCT characteristics such as study phase, sample size, country of first authors, specialty, trial registration, study design, type of analysis, comparator, and outcome measure. These characteristics did not appreciably affect the relation between financial ties and study outcomes (odds ratio 3.37, 1

  8. Clinical evaluation of the endothelial tie-2 crossmatch in ABO compatible and ABO incompatible renal transplants.

    Science.gov (United States)

    Kafetzi, Maria L; Boletis, John N; Melexopoulou, Christine A; Tsakris, Athanassios; Iniotaki, Aliki G; Doxiadis, Ilias I N

    2013-11-01

    The necessity of detection of other than the classical major histocompatibility complex (MHC) and MHC class I-related chain A (MICA) directed antibodies prior to organ transplantation has already been repeatedly reported. A commercial flow cytometric endothelial crossmatch (CM) using isolated peripheral blood tie-2 positive cells provides a tool to detect non-MHC antibodies in addition to antibodies directed to MHC class I and II. The vast majority of circulating tie-2 positive cells expresses HLA-DR but not the A, B blood group antigens. Tie-2 cells are circulating surrogate endothelial cells. In this retrospective study we evaluated the endothelial CM in 51 renal transplantations, 30 with ABO compatible grafts and 21 with ABO incompatible grafts. Fifteen of the ABO compatible recipients (group A) developed unexplained rejection episodes (RE) while the remaining 15 had no RE (group B). Five cases of group A and none of group B had a positive tie-2 CM before transplantation (p=0.042). A positive tie-2 CM was also correlated with graft failure in ABO compatible transplants (p=0.02). No significant correlation was found between a positive pre-transplant tie-2 CM and RE in the ABO incompatible group. This study strongly suggest that a positive tie-2 CM may predict post-transplantation complications in ABO compatible grafts while negative reactions are not predictive. The test is not significantly correlated with RE in ABO incompatible grafts possibly due to applied desensitization. Copyright © 2013 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

  9. Tie2 Expressing Monocytes in the Spleen of Patients with Primary Myelofibrosis.

    Directory of Open Access Journals (Sweden)

    Rita Campanelli

    Full Text Available Primary myelofibrosis (PMF is a Philadelphia-negative (Ph- myeloproliferative disorder, showing abnormal CD34+ progenitor cell trafficking, splenomegaly, marrow fibrosis leading to extensive extramedullary haematopoiesis, and abnormal neoangiogenesis in either the bone marrow or the spleen. Monocytes expressing the angiopoietin-2 receptor (Tie2 have been shown to support abnormal angiogenic processes in solid tumors through a paracrine action that takes place in proximity to the vessels. In this study we investigated the frequency of Tie2 expressing monocytes in the spleen tissue samples of patients with PMF, and healthy subjects (CTRLs, and evaluated their possible role in favouring spleen angiogenesis. We show by confocal microscopy that in the spleen tissue of patients with PMF, but not of CTRLs, the most of the CD14+ cells are Tie2+ and are close to vessels; by flow cytometry, we found that Tie2 expressing monocytes were Tie2+CD14lowCD16brightCDL62-CCR2- (TEMs and their frequency was higher (p = 0.008 in spleen tissue-derived mononuclear cells (MNCs of patients with PMF than in spleen tissue-derived MNCs from CTRLs undergoing splenectomy for abdominal trauma. By in vitro angiogenesis assay we evidenced that conditioned medium of immunomagnetically selected spleen tissue derived CD14+ cells of patients with PMF induced a denser tube like net than that of CTRLs; in addition, CD14+Tie2+ cells sorted from spleen tissue derived single cell suspension of patients with PMF show a higher expression of genes involved in angiogenesis than that found in CTRLs. Our results document the enrichment of Tie2+ monocytes expressing angiogenic genes in the spleen of patients with PMF, suggesting a role for these cells in starting/maintaining the pathological angiogenesis in this organ.

  10. Soluble Tie2 overrides the heightened invasion induced by anti-angiogenesis therapies in gliomas.

    Science.gov (United States)

    Cortes-Santiago, Nahir; Hossain, Mohammad B; Gabrusiewicz, Konrad; Fan, Xuejun; Gumin, Joy; Marini, Frank C; Alonso, Marta M; Lang, Frederick; Yung, W K; Fueyo, Juan; Gomez-Manzano, Candelaria

    2016-03-29

    Glioblastoma recurrence after treatment with the anti-vascular endothelial growth factor (VEGF) agent bevacizumab is characterized by a highly infiltrative and malignant behavior that renders surgical excision and chemotherapy ineffective. Our group has previously reported that Tie2-expressing monocytes (TEMs) are aberrantly present at the tumor/normal brain interface after anti-VEGF therapies and their significant role in the invasive outgrowth of these tumors. Here, we aimed to further understand the mechanisms leading to this pro-invasive tumor microenvironment. Examination of a U87MG xenogeneic glioma model and a GL261 murine syngeneic model showed increased tumor expression of angiopoietin 2 (Ang2), a natural ligand of Tie2, after anti-angiogenesis therapies targeting VEGF or VEGF receptor (VEGFR), as assessed by immunohistochemical analysis, immunofluorescence analysis, and enzyme-linked immunosorbent assays of tumor lysates. Migration and gelatinolytic assays showed that Ang2 acts as both a chemoattractant of TEMs and an enhancing signal for their tumor-remodeling properties. Accordingly, in vivo transduction of Ang2 into intracranial gliomas increased recruitment of TEMs into the tumor. To reduce invasive tumor outgrowth after anti-angiogenesis therapy, we targeted the Ang-Tie2 axis using a Tie2 decoy receptor. Using syngeneic models, we observed that overexpression of soluble Tie2 within the tumor prevented the recruitment of TEMs to the tumor and the development of invasion after anti-angiogenesis treatment. Taken together, these data indicate an active role for the Ang2-Tie2 pathway in invasive glioma recurrence after anti-angiogenesis treatment and provide a rationale for testing the combined targeting of VEGF and Ang-Tie2 pathways in patients with glioblastoma.

  11. Covering a Crucible with Metal Containing Channels

    Science.gov (United States)

    Grugel, Richard N.

    2006-01-01

    In a procedure that partly resembles the lost-wax casting process, a crucible made of a brittle material (ceramic, quartz, or glass) is covered with a layer of metal containing channels. The metal cover and the channels can serve any or all of several purposes, depending upon the application: Typically, the metal would serve at least partly to reinforce the crucible. The channels could be used as passages for narrow objects that could include thermocouples and heat-transfer strips. Alternatively or in addition, channels could be used as flow paths for liquid or gaseous coolants and could be positioned and oriented for position- or direction-selective cooling. In some cases, the channels could be filled with known gases and sealed so that failure of the crucibles could be indicated by instruments that detect the gases. The process consists of three main steps. In the first step, a pattern defining the channels is formed by wrapping or depositing a material in the desired channel pattern on the outer surface of the crucible. The pattern material can be a plastic, wax, low-ash fibrous material, a soluble material, or other suitable material that can subsequently be removed easily. In a proof-of-concept demonstration (see figure), the crucible was an alumina cylinder and the mold material was plastic tie-down tape. In the second step, the patterned crucible is coated with metal. In one variation of the second step, a very thin layer containing or consisting of an electrically conductive material (e.g., gold, silver, or carbon) is painted or otherwise deposited on the mold-covered crucible, then the covering metal required for the specific application is electrodeposited on the very thin conducting layer. In another variation of the second step, the metal coat is formed by chemical vapor deposition. In the proof-of-concept demonstration, a layer of nickel 0.003 in. ( 0.08 mm) thick was electrodeposited. In the third step, the patterned material is removed. This is

  12. USACE Navigation Channels 2012

    Data.gov (United States)

    California Natural Resource Agency — This dataset represents both San Francisco and Los Angeles District navigation channel lines. All San Francisco District channel lines were digitized from CAD files...

  13. Calcium channel blocker overdose

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/002580.htm Calcium-channel blocker overdose To use the sharing features on this page, please enable JavaScript. Calcium-channel blockers are a type of medicine used ...

  14. The social ties that bind: social anxiety and academic achievement across the university years.

    Science.gov (United States)

    Brook, Christina A; Willoughby, Teena

    2015-05-01

    Given that engagement and integration in university/college are considered key to successful academic achievement, the identifying features of social anxiety, including fear of negative evaluation and distress and avoidance of new or all social situations, may be particularly disadvantageous in the social and evaluative contexts that are integral to university/college life. Thus, the purpose of this study was to examine the direct effects of social anxiety on academic achievement, as well as investigate an indirect mechanism through which social anxiety might impact on academic achievement, namely, the formation of new social ties in university. The participants were 942 (71.7 % female; M = 19 years at Time 1) students enrolled in a mid-sized university in Southern Ontario, Canada. Students completed annual assessments of social anxiety, social ties, and academic achievement for three consecutive years. The results from an autoregressive cross-lag path analysis indicated that social anxiety had a significant and negative direct relationship with academic achievement. Moreover, the negative indirect effect of social anxiety on academic achievement through social ties was significant, as was the opposing direction of effects (i.e., the indirect effect of academic achievement on social anxiety through social ties). These findings highlight the critical role that social ties appear to play in successful academic outcomes and in alleviating the effects of social anxiety during university/college.

  15. Platelet-rich plasma extract prevents pulmonary edema through angiopoietin-Tie2 signaling.

    Science.gov (United States)

    Mammoto, Tadanori; Jiang, Amanda; Jiang, Elisabeth; Mammoto, Akiko

    2015-01-01

    Increased vascular permeability contributes to life-threatening pathological conditions, such as acute respiratory distress syndrome. Current treatments for sepsis-induced pulmonary edema rely on low-tidal volume mechanical ventilation, fluid management, and pharmacological use of a single angiogenic or chemical factor with antipermeability activity. However, it is becoming clear that a combination of multiple angiogenic/chemical factors rather than a single factor is required for maintaining stable and functional blood vessels. We have demonstrated that mouse platelet-rich plasma (PRP) extract contains abundant angiopoietin (Ang) 1 and multiple other factors (e.g., platelet-derived growth factor), which potentially stabilize vascular integrity. Here, we show that PRP extract increases tyrosine phosphorylation levels of Tunica internal endothelial cell kinase (Tie2) and attenuates disruption of cell-cell junctional integrity induced by inflammatory cytokine in cultured human microvascular endothelial cells. Systemic injection of PRP extract also increases Tie2 phosphorylation in mouse lung and prevents endotoxin-induced pulmonary edema and the consequent decreases in lung compliance and exercise intolerance resulting from endotoxin challenge. Soluble Tie2 receptor, which inhibits Ang-Tie2 signaling, suppresses the ability of PRP extract to inhibit pulmonary edema in mouse lung. These results suggest that PRP extract prevents endotoxin-induced pulmonary edema mainly through Ang-Tie2 signaling, and PRP extract could be a potential therapeutic strategy for sepsis-induced pulmonary edema and various lung diseases caused by abnormal vascular permeability.

  16. IVF, same-sex couples and the value of biological ties.

    Science.gov (United States)

    Di Nucci, Ezio

    2016-12-01

    Ought parents, in general, to value being biologically tied to their children? Is it important, in particular, that both parents be biologically tied to their children? I will address these fundamental questions by looking at a fairly new practice within IVF treatments, so-called IVF-with-ROPA (Reception of Oocytes from Partner), which allows lesbian couples to 'share motherhood', with one partner providing the eggs while the other becomes pregnant. I believe that IVF-with-ROPA is, just like other IVF treatments, morally permissible, but here I argue that the increased biological ties which IVF-with-ROPA allows for do not have any particular value beside the satisfaction of a legitimate wish, because there is no intrinsic value in a biological tie between parents and children; further, I argue that equality within parental projects cannot be achieved by redistributing biological ties. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  17. Quantum Channels With Memory

    International Nuclear Information System (INIS)

    Rybar, T.

    2012-01-01

    Quantum memory channels represent a very general, yet simple and comprehensible model for causal processes. As such they have attracted considerable research interest, mostly aimed on their transfer capabilities and structure properties. Most notably it was shown that memory channels can be implemented via physically naturally motivated collision models. We also define the concept of repeatable channels and show that only unital channels can be implemented repeat ably with pure memory channels. In the special case of qubit channels we also show that every unital qubit channel has a repeatable implementation. We also briefly explore the possibilities of stroboscopical simulation of channels and show that all random unitary channels can be stroboscopically simulated. Particularly in qubit case, all indivisible qubit channels are also random unitary, hence for qubit all indivisible channels can be stroboscopically simulated. Memory channels also naturally capture the framework of correlated experiments. We develop methods to gather and interpret data obtained in such setting and in detail examine the two qubit case. We also show that for control unitary interactions the measured data will never contradict a simple unitary evolution. Thus no memory effects can be spotted then. (author)

  18. Eight channel fast scalar

    Energy Technology Data Exchange (ETDEWEB)

    Waddoup, W D; Stubbs, R J [Durham Univ. (UK)

    1977-11-01

    An eight channel 64-bit scaler has been constructed with a static CMOS memory. Scaling frequencies are independently variable, at each channel, as are the number of bits/channel. The scaler, when used in conjunction with a multichannel charge to time converter results in a very flexible, gated multichannel ADC.

  19. KV7 potassium channels

    DEFF Research Database (Denmark)

    Stott, Jennifer B; Jepps, Thomas Andrew; Greenwood, Iain A

    2014-01-01

    Potassium channels are key regulators of smooth muscle tone, with increases in activity resulting in hyperpolarisation of the cell membrane, which acts to oppose vasoconstriction. Several potassium channels exist within smooth muscle, but the KV7 family of voltage-gated potassium channels have been...

  20. Analysis and design of type b package tie-down systems

    International Nuclear Information System (INIS)

    Phalippou, C.; Tombini, C.; Tanguy, L.

    1993-01-01

    In order to analyse the incidence of tie-down conditions as a cause of road accidents and to advise carriers on methods of calculating the risk, the French Atomic Energy Commission (CEA), within the framework of a research contract financed by the European Community, conducted a survey into road accidents in which B type packages were involved. After analysis of the survey results, the CEA then conducted reduced scale tests on representative models to establish design rules for tie-down systems. These rules have been the subject of various publications and have at last resulted in the production of a software aid to the design and monitoring of tie-down systems. This document states the various stages involved in this work and the way in which the ARRIMAGE software is arranged. (J.P.N.)

  1. A matched Bow-tie antenna at 433MHz for use in underwater wireless sensor networks

    International Nuclear Information System (INIS)

    Abdou, A A; Shaw, A; Mason, A; Al-Shamma'a, A; Cullen, J; Wylie, S; Diallo, M

    2013-01-01

    Electromagnetic (EM) wave propagation underwater is been disregarded because of attenuation at high frequencies, however the theory predicts that propagation is possible at some useful distance in the lower Industrial, Scientific and Medical (ISM) band. Common transceivers rely on narrowband antennas and matching circuit. The aim of this paper is to design a broadband 433MHz bow-tie antenna and experiment it in air and water without a matching circuit. This antenna could be attached to wireless transceivers and form a Wireless Sensor Network for deployment in various underwater applications. The bow-tie antennas were designed, simulated and constructed in laboratory. Experiments were setup carefully by using a completely isolated transmitter from electronics to avoid airborne transmission. The 433MHz. bow-tie proved its suitability for use in Underwater.

  2. The effects of integration and transnational ties on international return migration intentions

    Directory of Open Access Journals (Sweden)

    Hein de Haas

    2011-12-01

    Full Text Available While return migration is receiving increasing attention, there is still insufficient insight into the factors which determine migrants' intentions and decisions to return. It is often assumed that integration in receiving countries and the concomitant weakening of transnational ties decreases the likelihood of returning. However, according to alternative theoretical interpretations, return migration can also be the outflow of successful integration in receiving countries. Drawing on a data set of four African immigrant groups in Spain and Italy, this articlereviews these conflicting hypotheses by assessing the effects of integration and transnational ties on return migration intentions. The results of the analysis suggest that socio-cultural integration has a negative effect on return migration intentions, while economic integration and transnational ties have more ambiguous and sometimes positive effects. The results provide mixed support for the different hypotheses but question theoretical perspectives that unequivocally conceptualizereturn migration and transnationalism as causes and/or consequences of "integration failure".

  3. An LLCL Power Filter for Single-Phase Grid-Tied Inverter

    DEFF Research Database (Denmark)

    Wu, Weimin; He, Yuanbin; Blaabjerg, Frede

    2012-01-01

    This paper presents a new topology of higher order power filter for grid-tied voltage-source inverters, named the LLCL filter, which inserts a small inductor in the branch loop of the capacitor in the traditional LCL filter to compose a series resonant circuit at the switching frequency. Particul......This paper presents a new topology of higher order power filter for grid-tied voltage-source inverters, named the LLCL filter, which inserts a small inductor in the branch loop of the capacitor in the traditional LCL filter to compose a series resonant circuit at the switching frequency...... to the inverter system control. The parameter design criteria of the proposed LLCL filter is also introduced. The comparative analysis and discussions regarding the traditional LCL filter and the proposed LLCL filter have been presented and evaluated through experiment on a 1.8-kW-single-phase grid-tied inverter...

  4. A community of strangers: the dis-embedding of social ties.

    Science.gov (United States)

    Parigi, Paolo; State, Bogdan; Dakhlallah, Diana; Corten, Rense; Cook, Karen

    2013-01-01

    In this paper we explore two contrasting perspectives on individuals' participation in associations. On the one hand, some have considered participation the byproduct of pre-existing friendship ties--the more friends one already has in the association, the more likely he or she is to participate. On the other hand, some have considered participation to be driven by the association's capacity to form new identities--the more new friends one meets in the association, the more likely he or she is to participate. We use detailed temporal data from an online association to adjudicate between these two mechanisms and explore their interplay. Our results show a significant impact of new friendship ties on participation, compared to a negligible impact of pre-existing friends, defined here as ties to other members formed outside of the organization's context. We relate this finding to the sociological literature on participation and we explore its implications in the discussion.

  5. A community of strangers: the dis-embedding of social ties.

    Directory of Open Access Journals (Sweden)

    Paolo Parigi

    Full Text Available In this paper we explore two contrasting perspectives on individuals' participation in associations. On the one hand, some have considered participation the byproduct of pre-existing friendship ties--the more friends one already has in the association, the more likely he or she is to participate. On the other hand, some have considered participation to be driven by the association's capacity to form new identities--the more new friends one meets in the association, the more likely he or she is to participate. We use detailed temporal data from an online association to adjudicate between these two mechanisms and explore their interplay. Our results show a significant impact of new friendship ties on participation, compared to a negligible impact of pre-existing friends, defined here as ties to other members formed outside of the organization's context. We relate this finding to the sociological literature on participation and we explore its implications in the discussion.

  6. A Synchronization Method for Single-Phase Grid-Tied Inverters

    DEFF Research Database (Denmark)

    Hadjidemetriou, Lenos; Kyriakides, Elias; Yang, Yongheng

    2016-01-01

    The controllers of single-phase grid-tied inverters require improvements to enable distribution generation systems to meet the grid codes/standards with respect to power quality and the fault ride through capability. In that case, the response of the selected synchronization technique is crucial...... for the performance of the entire grid-tied inverter. In this paper, a new synchronization method with good dynamics and high accuracy under a highly distorted voltage is proposed. This method uses a Multi-Harmonic Decoupling Cell (MHDC), which thus can cancel out the oscillations on the synchronization signals due...... to the harmonic voltage distortion while maintaining the dynamic response of the synchronization. Therefore, the accurate and dynamic response of the proposed MHDC-PLL can be beneficial for the performance of the whole single-phase grid-tied inverter....

  7. Let the Weakest Link Go! Empirical Explorations on the Relative Importance of Weak and Strong Ties on Social Networking Sites

    OpenAIRE

    Nicole C. Krämer; Leonie Rösner; Sabrina C. Eimler; Stephan Winter; German Neubaum

    2014-01-01

    Theoretical approaches as well as empirical results in the area of social capital accumulation on social networking sites suggest that weak ties/bridging versus strong ties/bonding social capital should be distinguished and that while bonding social capital is connected to emotional support, bridging social capital entails the provision of information. Additionally, recent studies imply the notion that weak ties/bridging social capital are gaining increasing importance in today’s social media...

  8. REGISTRATION OF LASER SCANNING POINT CLOUDS AND AERIAL IMAGES USING EITHER ARTIFICIAL OR NATURAL TIE FEATURES

    Directory of Open Access Journals (Sweden)

    P. Rönnholm

    2012-07-01

    Full Text Available Integration of laser scanning data and photographs is an excellent combination regarding both redundancy and complementary. Applications of integration vary from sensor and data calibration to advanced classification and scene understanding. In this research, only airborne laser scanning and aerial images are considered. Currently, the initial registration is solved using direct orientation sensors GPS and inertial measurements. However, the accuracy is not usually sufficient for reliable integration of data sets, and thus the initial registration needs to be improved. A registration of data from different sources requires searching and measuring of accurate tie features. Usually, points, lines or planes are preferred as tie features. Therefore, the majority of resent methods rely highly on artificial objects, such as buildings, targets or road paintings. However, in many areas no such objects are available. For example in forestry areas, it would be advantageous to be able to improve registration between laser data and images without making additional ground measurements. Therefore, there is a need to solve registration using only natural features, such as vegetation and ground surfaces. Using vegetation as tie features is challenging, because the shape and even location of vegetation can change because of wind, for example. The aim of this article was to compare registration accuracies derived by using either artificial or natural tie features. The test area included urban objects as well as trees and other vegetation. In this area, two registrations were performed, firstly, using mainly built objects and, secondly, using only vegetation and ground surface. The registrations were solved applying the interactive orientation method. As a result, using artificial tie features leaded to a successful registration in all directions of the coordinate system axes. In the case of using natural tie features, however, the detection of correct heights was

  9. Social position, social ties and adult's oral health: 13 year cohort study.

    Science.gov (United States)

    Vettore, Mario Vianna; Faerstein, Eduardo; Baker, Sarah Ruth

    2016-01-01

    This study explored different pathways by which social position and social ties influence adult's oral health over a 13-year period. A cohort investigation (Pro-Saúde Study) was conducted of non-faculty civil servants at a university in Rio de Janeiro, Brazil (N=1613). Baseline data collected in 1999 included age, social position, social ties, and access to dental care. Psychological factors and smoking were assessed in 2001, whereas tooth loss and self-rated oral health (SROH) were collected in 2012. A hypothesised model exploring different direct and indirect pathways was developed and tested using structural equation modelling. The model was a good fit to the data and accounted for 40% and 27% of the variance in tooth loss and SROH, respectively. A greater social position was linked to more social ties (β=0.31), health insurance (β=0.48), low psychological distress (β=0.07), less smoking (β=-0.21), more regular dental visiting (β=0.30), less tooth loss (β=-0.44) and better SROH (β=-0.25) over time. Social position (β=0.0005) and social ties (β=-0.0015) were linked indirectly with psychological distress, smoking and tooth loss. Social position was linked indirectly with social ties, psychological distress and SROH (β=-0.0071). Poor social position and weak social ties were important predictors for tooth loss and poor SROH in adults over the 13-year period. Direct and indirect pathways via psychological factors and smoking on the aforementioned relationships were identified, suggesting different areas of intervention to promote adults' oral health. Adult's oral health is influenced by social conditions through direct and indirect pathways, including via psychological factors and smoking. Copyright © 2015. Published by Elsevier Ltd.

  10. FEATURES OF DESIGN OF TIED-ARCH BRIDGES WITH FLEXIBLE INCLINED SUSPENSION HANGERS

    Directory of Open Access Journals (Sweden)

    V. O. Samosvat

    2017-10-01

    Full Text Available Purpose. Investigation and analysis of the hanger arrangement and the structural stability of a Network arch bridge – a tied-arch bridge with inclined hangers that cross each other at least twice. It is also necessary to make a comparative analysis with other types of hanger arrangements. Methodology. The authors in their research investigated a large number of parameters to determine their influence in the force distribution in the arch. Eventually they determined optimal values for all parameters. These optimal values allowed developing a design guide that leads to optimal arch design. When solving this problem, the authors used three-dimensional finite element models and the objective was to determine the most suitable solution for a road bridge, with a span of 100 meters, consisting of two inclined steel arches, located on a road with two traffic lanes, subjected to medium traffic. The virtual prototype of the model is performed by finite element simulator Midas Civil. Findings. In this study, for the bridge deck, a concrete tie appears to be the best solution considering the structural behavior of network arches, but economic advantages caused by easier erection may lead to steel or a composite bridge deck as better alternatives. Design requirements and local conditions of each particular bridge project will decide the most economic deck design.Originality. To ensure passenger comfort and the stability and continuity of the track, deformations of bridges are constricted. A network arch is a stiff structure with small deflections and therefore suitable to comply with such demands even for high speed railway traffic.
A network arch bridge with a concrete tie usually saves more than half the steel required for tied arches with vertical hangers and concrete ties. Practical value. Following the study design advice given in this article leads to savings of about 60 % of structural steel compared with conventional tied arch bridges with

  11. A 10-Year Follow-Up Study of Social Ties and Functional Health among the Old: The AGES Project.

    Science.gov (United States)

    Murata, Chiyoe; Saito, Tami; Tsuji, Taishi; Saito, Masashige; Kondo, Katsunori

    2017-07-03

    In Asian nations, family ties are considered important. However, it is not clear what happens among older people with no such ties. To investigate the association, we used longitudinal data from the Aichi Gerontological Evaluation Study (AGES) project. Functionally independent older people at baseline ( N = 14,088) in 10 municipalities were followed from 2003 to 2013. Social ties were assessed by asking about their social support exchange with family, relatives, friends, or neighbors. Cox proportional hazard models were employed to investigate the association between social ties and the onset of functional disability adjusting for age, health status, and living arrangement. We found that social ties with co-residing family members, and those with friends or neighbors, independently protected functional health with hazard ratios of 0.81 and 0.85 among men. Among women, ties with friend or neighbors had a stronger effect on health compared to their male counterparts with a hazard ratio of 0.89. The fact that social ties with friends or neighbors are associated with a lower risk of functional decline, independent of family support, serves to underscore the importance of promoting social ties, especially among those lacking family ties.

  12. Artifacts in magnetic spirals retrieved by transport of intensity equation (TIE)

    Science.gov (United States)

    Cui, J.; Yao, Y.; Shen, X.; Wang, Y. G.; Yu, R. C.

    2018-05-01

    The artifacts in the magnetic structures reconstructed from Lorentz transmission electron microscopy (LTEM) images with TIE method have been analyzed in detail. The processing for the simulated images of Bloch and Neel spirals indicated that the improper parameters in TIE may overestimate the high frequency information and induce some false features in the retrieved images. The specimen tilting will further complicate the analysis of the images because the LTEM image contrast is not the result of the magnetization distribution within the specimen but the integral projection pattern of the magnetic induction filling the entire space including the specimen.

  13. United States, Europe and Poland Different Stages of Antitrust Tying War in the New Economy

    Directory of Open Access Journals (Sweden)

    Mariusz SWORA

    2006-06-01

    Full Text Available Microsoft’s case has led to heated debates, both in Europe and the United States of America, on the abuse of the dominant position and on the prohibition of tying. This discussion, both in Europe and the United States, is not finished. In this article the author presents legal implications of tying products in Europe and Poland and confronts them with the American approach to tying. In Poland, a country with a fast developing economy, with the growing level of foreign investments, discussion on monopolist practices under the conditions of a fast technological development1 has not really commenced yet. The problems of innovation and development of New Economy undertakings has gained new impetus following Poland’s accession to the European Union. It is a matter of time when the anti-trust law begins to show interest in them. There are some indications that this has already taken place. In the first part of this article the author briefly presents the discussion related to Microsoft III case in the United States insofar as it pertains to New Economy issues. The second and third parts address legal and political aspects of the Microsoft case in the European Union. In the fourth part legal aspects related to tying practices in Poland are presented. The article aims to show that instrumental and mechanical treatment of tying practices used by firms having the market power under conditions of technological progress is not proper. The problem of antitrust analysis of such practices is universal, as universal as these practices are. However, the problem is solved differently in the United States and in Europe and the reasons for such a different approach are rooted in the legal system and policy enforcement. Microsoft antitrust is global. After US and European cases, Korean competition authority has found Microsoft guilty of tying practices2. Regarding Microsoft problems with tying it is necessary to ask the question whether tying practices are

  14. Do recruitment ties affect wages? An analysis using matched employer-employee data from Vietnam

    DEFF Research Database (Denmark)

    Larsen, Anna Folke; Rand, John; Torm, Nina Elisabeth

    2011-01-01

    This paper examines the extent to which recruitment ties affect individual wage outcomes in small and medium scale manufacturing firms. Based on a unique matched employer–employee dataset from Vietnam the authors find that there is a significant positive wage premium associated with obtaining a job...... through an informal contact, when controlling for standard determinants of wage compensation. Moreover, they show that the mechanism through which informal contacts affect wages depends on the type of recruitment tie used. The findings are robust across location, firm size categories, and different worker...

  15. Frequency Adaptive Repetitive Control of Grid-Tied Three-Phase PV Inverters

    DEFF Research Database (Denmark)

    Zhou, Keliang; Yang, Yongheng; Blaabjerg, Frede

    2016-01-01

    Repetitive control offers an accurate current control scheme for grid-tied converters to feed high quality sinusoidal current into the grid. However, with grid frequency being treated as a constant value, conventional repetitive controller fail to produce high quality feeding current in the prese......Repetitive control offers an accurate current control scheme for grid-tied converters to feed high quality sinusoidal current into the grid. However, with grid frequency being treated as a constant value, conventional repetitive controller fail to produce high quality feeding current...

  16. "People Are Either Too Fake or Too Real": Opportunities and Challenges in Tie-Based Anonymity

    DEFF Research Database (Denmark)

    Ma, Xiao; Andabili, Nazanin; Barkhuus, Louise

    2017-01-01

    In recent years, several mobile applications allowed individuals to anonymously share information with friends and contacts, without any persistent identity marker. The functions of these “tie-based” anonymity services may be notably different than other social media services. We use semi-structu...... disclosure needs and social probing. Still, challenges for making such applications successful, for example the prevalence of negativity and bullying, are substantial.......In recent years, several mobile applications allowed individuals to anonymously share information with friends and contacts, without any persistent identity marker. The functions of these “tie-based” anonymity services may be notably different than other social media services. We use semi...

  17. The centrality of social ties to climate migration and mental health.

    Science.gov (United States)

    Torres, Jacqueline M; Casey, Joan A

    2017-07-06

    Climate change-related hazards and disasters, known to adversely impact physical and mental health outcomes, are also expected to result in human migration above current levels. Environmentally-motivated migration and displacement may lead to the disruption of existing social ties, with potentially adverse consequences for mobile populations as well as their family members who remain in places of origin. We propose that the disruption of social ties is a key mechanism by which climate-related migration may negatively impact mental health, in particular. Existing social ties may provide social and material resources that buffer mental health stressors related to both prolonged and acute climate events. Preparation for such events may also strengthen these same ties and protect mental health. Communities may leverage social ties, first to mitigate climate change, and second, to adapt and rebuild post-disaster in communities of origin. Additionally, social ties can inform migration decisions and destinations. For example, scholars have found that the drought-motivated adaptive migration of West African Fulbe herders only occurred because of the long-term development of social networks between migrants and non-migrants through trade and seasonal grazing. On the other hand, social ties do not always benefit mental health. Some migrants, including those from poor regions or communities with no formal safety net, may face considerable burden to provide financial and emotional resources to family members who remain in countries of origin. In destination communities, migrants often face significant social marginalization. Therefore, policies and programs that aim to maintain ongoing social ties among migrants and their family and community members may be critically important in efforts to enhance population resilience and adaptation to climate change and to improve mental health outcomes. Several online platforms, like Refugee Start Force, serve to integrate refugees by

  18. The centrality of social ties to climate migration and mental health

    Directory of Open Access Journals (Sweden)

    Jacqueline M. Torres

    2017-07-01

    Full Text Available Abstract Climate change-related hazards and disasters, known to adversely impact physical and mental health outcomes, are also expected to result in human migration above current levels. Environmentally-motivated migration and displacement may lead to the disruption of existing social ties, with potentially adverse consequences for mobile populations as well as their family members who remain in places of origin. We propose that the disruption of social ties is a key mechanism by which climate-related migration may negatively impact mental health, in particular. Existing social ties may provide social and material resources that buffer mental health stressors related to both prolonged and acute climate events. Preparation for such events may also strengthen these same ties and protect mental health. Communities may leverage social ties, first to mitigate climate change, and second, to adapt and rebuild post-disaster in communities of origin. Additionally, social ties can inform migration decisions and destinations. For example, scholars have found that the drought-motivated adaptive migration of West African Fulbe herders only occurred because of the long-term development of social networks between migrants and non-migrants through trade and seasonal grazing. On the other hand, social ties do not always benefit mental health. Some migrants, including those from poor regions or communities with no formal safety net, may face considerable burden to provide financial and emotional resources to family members who remain in countries of origin. In destination communities, migrants often face significant social marginalization. Therefore, policies and programs that aim to maintain ongoing social ties among migrants and their family and community members may be critically important in efforts to enhance population resilience and adaptation to climate change and to improve mental health outcomes. Several online platforms, like Refugee Start Force

  19. Fine Channel Networks

    Science.gov (United States)

    1997-01-01

    A color image of fine channel networks on Mars; north toward top. The scene shows heavily cratered highlands dissected by dendritic open channel networks that dissect steep slopes of impact crater walls. This image is a composite of Viking high-resolution images in black and white and low-resolution images in color. The image extends from latitude 9 degrees S. to 5 degrees S. and from longitude 312 degrees to 320 degrees; Mercator projection. The dendritic pattern of the fine channels and their location on steep slopes leads to the interpretation that these are runoff channels. The restriction of these types of channels to ancient highland rocks suggests that these channels are old and date from a time on Mars when conditions existed for precipitation to actively erode rocks. After the channels reach a low plain, they appear to end. Termination may have resulted from burial by younger deposits or perhaps the flows percolated into the surface materials and continued underground.

  20. Ion channels in plants.

    Science.gov (United States)

    Hedrich, Rainer

    2012-10-01

    Since the first recordings of single potassium channel activities in the plasma membrane of guard cells more than 25 years ago, patch-clamp studies discovered a variety of ion channels in all cell types and plant species under inspection. Their properties differed in a cell type- and cell membrane-dependent manner. Guard cells, for which the existence of plant potassium channels was initially documented, advanced to a versatile model system for studying plant ion channel structure, function, and physiology. Interestingly, one of the first identified potassium-channel genes encoding the Shaker-type channel KAT1 was shown to be highly expressed in guard cells. KAT1-type channels from Arabidopsis thaliana and its homologs from other species were found to encode the K(+)-selective inward rectifiers that had already been recorded in early patch-clamp studies with guard cells. Within the genome era, additional Arabidopsis Shaker-type channels appeared. All nine members of the Arabidopsis Shaker family are localized at the plasma membrane, where they either operate as inward rectifiers, outward rectifiers, weak voltage-dependent channels, or electrically silent, but modulatory subunits. The vacuole membrane, in contrast, harbors a set of two-pore K(+) channels. Just very recently, two plant anion channel families of the SLAC/SLAH and ALMT/QUAC type were identified. SLAC1/SLAH3 and QUAC1 are expressed in guard cells and mediate Slow- and Rapid-type anion currents, respectively, that are involved in volume and turgor regulation. Anion channels in guard cells and other plant cells are key targets within often complex signaling networks. Here, the present knowledge is reviewed for the plant ion channel biology. Special emphasis is drawn to the molecular mechanisms of channel regulation, in the context of model systems and in the light of evolution.

  1. Compound Wiretap Channels

    Directory of Open Access Journals (Sweden)

    Shlomo Shamai (Shitz

    2009-01-01

    Full Text Available This paper considers the compound wiretap channel, which generalizes Wyner's wiretap model to allow the channels to the (legitimate receiver and to the eavesdropper to take a number of possible states. No matter which states occur, the transmitter guarantees that the receiver decodes its message and that the eavesdropper is kept in full ignorance about the message. The compound wiretap channel can also be viewed as a multicast channel with multiple eavesdroppers, in which the transmitter sends information to all receivers and keeps the information secret from all eavesdroppers. For the discrete memoryless channel, lower and upper bounds on the secrecy capacity are derived. The secrecy capacity is established for the degraded channel and the semideterministic channel with one receiver. The parallel Gaussian channel is further studied. The secrecy capacity and the secrecy degree of freedom (s.d.o.f. are derived for the degraded case with one receiver. Schemes to achieve the s.d.o.f. for the case with two receivers and two eavesdroppers are constructed to demonstrate the necessity of a prefix channel in encoder design. Finally, the multi-antenna (i.e., MIMO compound wiretap channel is studied. The secrecy capacity is established for the degraded case and an achievable s.d.o.f. is given for the general case.

  2. Compound Wiretap Channels

    Directory of Open Access Journals (Sweden)

    Kramer Gerhard

    2009-01-01

    Full Text Available Abstract This paper considers the compound wiretap channel, which generalizes Wyner's wiretap model to allow the channels to the (legitimate receiver and to the eavesdropper to take a number of possible states. No matter which states occur, the transmitter guarantees that the receiver decodes its message and that the eavesdropper is kept in full ignorance about the message. The compound wiretap channel can also be viewed as a multicast channel with multiple eavesdroppers, in which the transmitter sends information to all receivers and keeps the information secret from all eavesdroppers. For the discrete memoryless channel, lower and upper bounds on the secrecy capacity are derived. The secrecy capacity is established for the degraded channel and the semideterministic channel with one receiver. The parallel Gaussian channel is further studied. The secrecy capacity and the secrecy degree of freedom ( are derived for the degraded case with one receiver. Schemes to achieve the for the case with two receivers and two eavesdroppers are constructed to demonstrate the necessity of a prefix channel in encoder design. Finally, the multi-antenna (i.e., MIMO compound wiretap channel is studied. The secrecy capacity is established for the degraded case and an achievable is given for the general case.

  3. ATP Release Channels

    Directory of Open Access Journals (Sweden)

    Akiyuki Taruno

    2018-03-01

    Full Text Available Adenosine triphosphate (ATP has been well established as an important extracellular ligand of autocrine signaling, intercellular communication, and neurotransmission with numerous physiological and pathophysiological roles. In addition to the classical exocytosis, non-vesicular mechanisms of cellular ATP release have been demonstrated in many cell types. Although large and negatively charged ATP molecules cannot diffuse across the lipid bilayer of the plasma membrane, conductive ATP release from the cytosol into the extracellular space is possible through ATP-permeable channels. Such channels must possess two minimum qualifications for ATP permeation: anion permeability and a large ion-conducting pore. Currently, five groups of channels are acknowledged as ATP-release channels: connexin hemichannels, pannexin 1, calcium homeostasis modulator 1 (CALHM1, volume-regulated anion channels (VRACs, also known as volume-sensitive outwardly rectifying (VSOR anion channels, and maxi-anion channels (MACs. Recently, major breakthroughs have been made in the field by molecular identification of CALHM1 as the action potential-dependent ATP-release channel in taste bud cells, LRRC8s as components of VRACs, and SLCO2A1 as a core subunit of MACs. Here, the function and physiological roles of these five groups of ATP-release channels are summarized, along with a discussion on the future implications of understanding these channels.

  4. Single-port laparoscopic ovariectomy using a pre-tied loop ligature in Santa Ines ewes

    Directory of Open Access Journals (Sweden)

    Felipe Farias Pereira da Câmara Barros

    2015-11-01

    Full Text Available ABSTRACT: The aim of the study was to develop and assess the feasibility, postoperative pain and inflammatory response of the single-port laparoscopic ovariectomy in ewes, using a simple pre-tied loop ligature technique. Pre-tied Meltzer's knot was employed for prophylactic hemostasis of the ovarian pedicle. Slipknot was inserted within the abdominal cavity through a 14-gauge needle and tied surrounding the ovarian pedicle. Mean surgical time, manipulation, ligature and resection of each ovary and anesthesia time were 63±20, 20±10 and 91±26 minutes, respectively. No bleeding occurred during the surgeries. Ewes showed low scores pain (0.5±0.5 at all time-points. Postsurgical plasma fibrinogen was within the normal range for sheep specie at all time-points. The ewes showed a significant weight gain in comparison to the basal scaling (one day before the surgery. Single-port laparoscopic ovariectomy using a pre-tied loop ligature is feasible in the ovine specie and provided minimal postoperative distress and quick weight gain.

  5. The Role of Social Ties in Word-of-Mouth Effectiveness

    DEFF Research Database (Denmark)

    Martensen, Anne Duhr; Grønholdt, Lars

    2015-01-01

    This article develops consumer segmentation based on the strength of social ties in word-of-mouth (WOM) communication and examines the influence of WOM on behavioral attitude and intention in these segments. Data were collected through a survey among receivers of retail banking WOM. A cluster...

  6. The Ties That Bind: Linkages among Secondary Schools, Two-Year Colleges, and Baccalaureate Institutions.

    Science.gov (United States)

    Lorence, James J.

    This document discusses the roles of secondary schools, two-year colleges, and the upper level university in the University of Wisconsin System. Because of close ties with the host communities, Wisconsin's two-year institutions are uniquely situated to function as community resources. The paper discusses the advantages of a collaborative…

  7. From Gut Knowing: Every Silver Cloud Has a Black Lining. Actor Reflections on "Ties That Bind."

    Science.gov (United States)

    Elmes, Michael

    2003-01-01

    Makes sense of the performance of Steve Taylor's play, "Ties That Bind," from the perspective of the actors, 14 faculty members, and doctoral students from various universities in the United States by using the interpretive lens of Erving Goffman's Presentation of Self in Everyday Life. (SG)

  8. Social ties within school classes : The roles of gender, ethnicity, and having older siblings

    NARCIS (Netherlands)

    Soetevent, AR; Kooreman, P

    2005-01-01

    In this paper we identify the lines along which social ties between high-school teenagers are primarily formed. To this end, we introduce interaction weights between pupils in the same school class that are a function of exogenous individual background characteristics, such as gender, ethnicity, and

  9. Magnetic perturbations seen by CHAMP and evaluated using the TIE-GCM

    Directory of Open Access Journals (Sweden)

    D. T. Mozzoni

    2007-07-01

    Full Text Available The Thermosphere-Ionosphere Electrodynamics General Circulation Model (TIE-GCM is a self-consistent, global, atmospheric model that can be used to estimate magnetic perturbations at satellite altitude. These computed perturbations can then be compared with the magnetic vector data provided by low-earth orbiting satellites. In this initial study, the quietest day of each month from 2001–2005 was selected for comparison. CHAMP magnetic vector residuals were computed for these intervals using the CHAOS model to remove core and crustal geomagnetic contributions. Under various input parameters, the TIE-GCM predictions were compared with the CHAMP residuals on an orbit by orbit basis. Initial results demonstrate a reasonable agreement between the TIE-GCM estimates and the CHAMP residuals in non-polar, dayside regions (±50° magnetic latitude where both are able to resolve the Equatorial Electro-Jet (EEJ and solar quiet (Sq current systems. Although no clear component or temporal correlation was discerned, evidence showing the decrease in residual comparisons presents the possibility of using the TIE-GCM to pre-process geomagnetic data for main field modeling purposes.

  10. Which Peers Matter: How Social Ties Affect Peer-Group Effects

    Science.gov (United States)

    Poldin, Oleg; Valeeva, Diliara; Yudkevich, Maria

    2016-01-01

    We study how the achievements of university students are influenced by the characteristics and achievements of peers in individuals' social networks. Defining peer group in terms of friendship and study partner ties enables us to apply a network regression model and thereby disentangle the influence of peers' performance from that of peers'…

  11. Peer monitoring, social ties and moral hazard in group lending programmes : evidence from Eritrea

    NARCIS (Netherlands)

    Hermes, C.L.M.; Lensink, B.W.; Mehrteab, H.T.

    2003-01-01

    In this paper, we provide an empirical analysis of the impact of monitoring and social ties within group lending programs on moral hazard behavior of its participants, based on data from an extensive questionnaire held in Eritrea among participants of 102 groups. We find support for the fact that

  12. Peer monitoring, social ties and moral hazard in group lending programs : Evidence from Eritrea

    NARCIS (Netherlands)

    Hermes, N; Lensink, R; Mehrteab, HT

    In this paper, we investigate the impact of monitoring and social ties on moral hazard behavior within group lending programs. Our study is based on data from an extensive questionnaire held in Eritrea among participants of 102 groups. We separately analyze the impact of group leaders and other

  13. Quiet eye training improves surgical knot tying more than traditional technical training: a randomized controlled study.

    Science.gov (United States)

    Causer, Joe; Harvey, Adrian; Snelgrove, Ryan; Arsenault, Gina; Vickers, Joan N

    2014-08-01

    We examined the effectiveness of technical training (TT) and quiet eye training (QE) on the performance of one-handed square knot tying in surgical residents. Twenty surgical residents were randomly assigned to the 2 groups and completed pretest, training, retention, and transfer tests. Participants wore a mobile eye tracker that simultaneously recorded their gaze and hand movements. Dependent variables were knot tying performance (%), QE duration (%), number of fixations, total movement time (s), and hand movement phase time (s). The QE training group had significantly higher performance scores, a longer QE duration, fewer fixations, faster total knot tying times, and faster movement phase times compared with the TT group. The QE group maintained performance in the transfer test, whereas the TT group significantly decreased performance from retention to transfer. QE training significantly improved learning, retention, and transfer of surgical knot tying compared with a traditional technical approach. Both performance effectiveness (performance outcome) and movement efficiency (hand movement times) were improved using QE modeling, instruction, and feedback. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Design of squat shear walls using continuous strut-and-tie resistant models

    International Nuclear Information System (INIS)

    Santos, S.H. de C; Silva, R.E. da

    1993-01-01

    A new approach is presented for designing squat shear walls, subjected to seismic loading. In this approach, the strut-and-tie resistant models, proposed by Schlaich et al., are generalized in order to analyze continuous fields of compression and tension stresses. The application of the presented methodology is illustrated through numerical examples. (author)

  15. Predicting a dissociative disorder from type of childhood maltreatment and abuser-abused relational tie.

    Science.gov (United States)

    Krüger, Christa; Fletcher, Lizelle

    2017-01-01

    We investigate the types of childhood maltreatment and abuser-abused relational ties that best predict a dissociative disorder (DD). Psychiatric inpatients (n = 116; mean age = 35; F:M = 1.28:1) completed measures of dissociation and trauma. Abuse type and abuser-abused relational ties were recorded in the Traumatic Experiences Questionnaire. Multidisciplinary team clinical diagnosis or administration of the SCID-D-R to high dissociators confirmed DD diagnoses. Logit models described the relationships between abuser-abused relational tie and the diagnostic grouping of patients, DD present (n = 16) or DD absent (n = 100). Fisher's exact tests measured the relative contribution of specific abuse types. There was a positive relationship between abuse frequency and the presence of DD. DD patients experienced more abuse than patients without DDs. Two combinations of abuse type and relational tie predicted a DD: childhood emotional neglect by biological parents/siblings and later emotional abuse by intimate partners. These findings support the early childhood etiology of DDs and subsequent maladaptive cycles of adult abuse. Enquiries about childhood maltreatment should include a history of emotional neglect by biological parents/siblings. Adult emotional abuse by intimate partners should assist in screening for DDs.

  16. An Agent Model for a Human’s Social Support Network Tie Preference During Depression

    NARCIS (Netherlands)

    Aziz, A.A.; Klein, M.C.A.; Treur, J.; Baeza-Yates, R.; Lang, J.; Mitra, S.; Parsons, S.; Pasi, G.

    2009-01-01

    Seeking support from their environment is important for people suffering from a depression. People usually have different social networks to which they are attached with different ties. In this paper, a computational model is presented that describes the selection of network members for seeking

  17. Ties between parents and their adult children: a Western European typology of late-life families

    NARCIS (Netherlands)

    Dykstra, P.A.; Fokkema, C.M.

    2011-01-01

    Following Reher’s (1998) seminal paper on family ties in western Europe, the perspective that family solidarity patterns are divided along the lines of an individualistic north and a familialistic south has dominated the research literature. We challenge this view and address variability in

  18. The effects of integration and transnational ties on international return migration intentions

    NARCIS (Netherlands)

    de Haas, H.; Fokkema, C.M.

    2011-01-01

    While return migration is receiving increasing attention, there is still insufficient insight into the factors which determine migrants’ intentions and decisions to return. It is often assumed that integration in receiving countries and the concomitant weakening of transnational ties decreases the

  19. Measurement of flow phenomena in the vicinity of a PWR tie plate geometry. Final report

    International Nuclear Information System (INIS)

    Lee, R.S.L.; Srinivasan, J.; Cho, S.K.; Wang, J.L.

    1981-01-01

    The flow of an air-water droplet dispersion in a simulated 3D test section in the reflood portion of LOCA is studied. For this purpose, a new scheme of Laser-Doppler Anemometry for the simultaneous measurement of size and velocity of large-size (0.5mm-6mm) droplets has been developed and utilized. In terms of droplet reentrainment from the tie-plate, three flow regimes have been identified, depending on the velocity level of the flow; the dome formation stage, the oscillating dome stage and the wall film breaking up stage. Detailed measurements have been made in these regimes to obtain the local droplet sizes, droplet velocity distribution, air velocity distributions and momentum flux of both incoming and outgoing dispersion through the tie-plate. It has been observed that the size distribution of the reentrained droplets depends mainly on the flow regimes and is essentially independent of that of the incoming dispersion below the tie-plate. These reentrained droplets are found to be mostly in the neighborhood of 1mm in size and their trajectories on leaving the tie-plate essentially oriented close to the vertical direction. Also the momentum flux of outgoing dispersion differs from that of the incoming dispersion. The measuring technique, the experimental set-up, on-line data acquisition system and the results of the measurements are reported

  20. Third Party Referrals in the Venture Capital Financing Process: Do Network Ties Matter?

    NARCIS (Netherlands)

    Heuven, J.M.J.

    2008-01-01

    In this paper we focus on the role of third party referrals in the venture capital funding process. Taking network theory as our theoretical perspective we explore if and how third parties play a role in the funding process. Hereby we focus on both the network ties between new venture teams and

  1. Modelling of bow-tie microstrip antennas using modified locally conformal FDTD method

    NARCIS (Netherlands)

    George, J.

    2000-01-01

    An analysis of bow-tie microstrip antennas is presented based on the use of the modified locally conformal finite-difference time-domain (FDTD) method. This approach enables the number of cells along the antenna length and width to be chosen independently of the antenna central width, which helps to

  2. Stress wave techniques for determining quality of dimensional lumber from switch ties

    Science.gov (United States)

    K. C. Schad; D. E. Kretschmann; K. A. McDonald; R. J. Ross; D. W. Green

    1995-01-01

    Researchers at the Forest Products Laboratory, USDA Forest Service, have been studying nondestructive techniques for evaluating the strength of wood. This report describes the results of a pilot study on using these techniques to determine the quality of large dimensional lumber cut from switch ties. First, pulse echo and dynamic (transverse vibration) techniques were...

  3. 75 FR 9691 - Review of the Commission's Program Access Rules and Examination of Programming Tying Arrangements

    Science.gov (United States)

    2010-03-03

    ... involving programming they own, that impede competition in the video distribution market. See H.R. Rep. No... availability of programming and charging discriminatory prices to non- cable technologies.'' H.R. Rep. No. 102... Access Rules and Examination of Programming Tying Arrangements; Final Rule #0;#0;Federal Register / Vol...

  4. Founding a business inspired by close entrepreneurial ties: Does it matter for survival?

    NARCIS (Netherlands)

    de Jong, J.P.J.; Marsili, O.

    2015-01-01

    Founding a business may be inspired by close entrepreneurial ties, that is, business-owning relatives or friends. We analyze if and when such inspiration is associated with post-entry survival. Drawing on longitudinal data on 942 founders, we find a positive relationship only if founders start by

  5. Which Peers Matter : How Social Ties Affect Peer-group Effects

    NARCIS (Netherlands)

    Poldin, O.; Valeeva, D.; Yudkevich, M.

    We study how the achievements of university students are influenced by the characteristics and achievements of peers in individuals’ social networks. Defining peer group in terms of friendship and study partner ties enables us to apply a network regression model and thereby disentangle the influence

  6. Application of the Bow Tie method for evaluation of safety in the procedure of logging wells

    International Nuclear Information System (INIS)

    Alfonso Pallares, C; Perez Reyes, Y.; Sarabia Molina, I.I.

    2013-01-01

    This work consists of an assessment of security in the practice of logging of oil wells, using the method of Bow Tie for being a simple method of evaluation of the risk, which makes it possible in a structured way to set priorities to manage risk

  7. Escapist Motives for On-line Gaming and Strengthening of Weak Ties

    DEFF Research Database (Denmark)

    Sudzina, Frantisek; Razmerita, Liana

    on-line gaming. The research investigates Facebook and other on-line games separate-ly. A surprising result is that while most of the investigated escapist motives are positively correlated with strengthening of weak ties, the mundane breaking motive is negatively correlated with strengthening...

  8. Preservation and Dissolution of the Target Firm's Embedded Ties in Acquisitions

    NARCIS (Netherlands)

    S. Spedale-Latimer (Simona); F.A.J. van den Bosch (Frans); H.W. Volberda (Henk)

    2006-01-01

    textabstractOur study builds on extant theory on embeddness to concentrate on the process of preservation and dissolution of the target firm’s embedded ties in acquisitions. We identify four critical areas - communication, idiosyncratic investments, inter-personal relations and, personnel turnover –

  9. Impact of Group Emotions on Student Collective Action Tendencies, Ties, and Task Performance

    Science.gov (United States)

    Sundararajan, Malavika; Sundararajan, Binod; Manderson, Jill

    2016-01-01

    The authors tested the dynamics of collective action tendencies of student teams when trying to accomplish a shared goal, with a focus on the impact of member ties and team member interaction and emotional responses on team performance. The results show the direct and indirect impacts of both positive and negative group emotions on the student…

  10. Identification of proangiogenic TIE2-expressing monocytes (TEMs) in human peripheral blood and cancer.

    Science.gov (United States)

    Venneri, Mary Anna; De Palma, Michele; Ponzoni, Maurilio; Pucci, Ferdinando; Scielzo, Cristina; Zonari, Erika; Mazzieri, Roberta; Doglioni, Claudio; Naldini, Luigi

    2007-06-15

    Tumor-infiltrating myeloid cells, including tumor-associated macrophages (TAMs), have been implicated in tumor progression. We recently described a lineage of mouse monocytes characterized by expression of the Tie2 angiopoietin receptor and required for the vascularization and growth of several tumor models. Here, we report that TIE2 expression in human blood identifies a subset of monocytes distinct from classical inflammatory monocytes and comprised within the less abundant "resident" population. These TIE2-expressing monocytes (TEMs) accounted for 2% to 7% of blood mononuclear cells in healthy donors and were distinct from rare circulating endothelial cells and progenitors. In human cancer patients, TEMs were observed in the blood and, intriguingly, within the tumors, where they represented the main monocyte population distinct from TAMs. Conversely, TEMs were hardly detected in nonneoplastic tissues. In vitro, TEMs migrated toward angiopoietin-2, a TIE2 ligand released by activated endothelial cells and angiogenic vessels, suggesting a homing mechanism for TEMs to tumors. Purified human TEMs, but not TEM-depleted monocytes, markedly promoted angiogenesis in xenotransplanted human tumors, suggesting a potentially critical role of TEMs in human cancer progression. Human TEMs may provide a novel, biologically relevant marker of angiogenesis and represent a previously unrecognized target of cancer therapy.

  11. TIE2-expressing monocytes/macrophages regulate revascularization of the ischemic limb.

    Science.gov (United States)

    Patel, Ashish S; Smith, Alberto; Nucera, Silvia; Biziato, Daniela; Saha, Prakash; Attia, Rizwan Q; Humphries, Julia; Mattock, Katherine; Grover, Steven P; Lyons, Oliver T; Guidotti, Luca G; Siow, Richard; Ivetic, Aleksandar; Egginton, Stuart; Waltham, Matthew; Naldini, Luigi; De Palma, Michele; Modarai, Bijan

    2013-06-01

    A third of patients with critical limb ischemia (CLI) will eventually require limb amputation. Therapeutic neovascularization using unselected mononuclear cells to salvage ischemic limbs has produced modest results. The TIE2-expressing monocytes/macrophages (TEMs) are a myeloid cell subset known to be highly angiogenic in tumours. This study aimed to examine the kinetics of TEMs in patients with CLI and whether these cells promote neovascularization of the ischemic limb. Here we show that there are 10-fold more circulating TEMs in CLI patients, and removal of ischemia reduces their numbers to normal levels. TEM numbers in ischemic muscle are two-fold greater than normoxic muscle from the same patient. TEMs from patients with CLI display greater proangiogenic activity than TIE2-negative monocytes in vitro. Using a mouse model of hindlimb ischemia, lentiviral-based Tie2 knockdown in TEMs impaired recovery from ischemia, whereas delivery of mouse macrophages overexpressing TIE2, or human TEMs isolated from CLI patients, rescued limb ischemia. These data suggest that enhancing TEM recruitment to the ischemic muscle may have the potential to improve limb neovascularization in CLI patients. Copyright © 2013 The Authors. Published by John Wiley and Sons, Ltd on behalf of EMBO.

  12. Volume Regulated Channels

    DEFF Research Database (Denmark)

    Klausen, Thomas Kjær

    of volume perturbations evolution have developed system of channels and transporters to tightly control volume homeostasis. In the past decades evidence has been mounting, that the importance of these volume regulated channels and transporters are not restricted to the defense of cellular volume...... but are also essential for a number of physiological processes such as proliferation, controlled cell death, migration and endocrinology. The thesis have been focusing on two Channels, namely the swelling activated Cl- channel (ICl, swell) and the transient receptor potential Vanilloid (TRPV4) channel. I: Cl......- serves a multitude of functions in the mammalian cell, regulating the membrane potential (Em), cell volume, protein activity and the driving force for facilitated transporters giving Cl- and Cl- channels a major potential of regulating cellular function. These functions include control of the cell cycle...

  13. HIPPI and Fibre Channel

    International Nuclear Information System (INIS)

    Tolmie, D.E.

    1992-01-01

    The High-Performance Parallel Interface (HIPPI) and Fibre Channel are near-gigabit per second data communications interfaces being developed in ANSI standards Task Group X3T9.3. HIPPI is the current interface of choice in the high-end and supercomputer arena, and Fibre Channel is a follow-on effort. HIPPI came from a local area network background, and Fibre Channel came from a mainframe to peripheral interface background

  14. Nuclear reactor coolant channels

    International Nuclear Information System (INIS)

    Macbeth, R.V.

    1978-01-01

    Reference is made to coolant channels for pressurised water and boiling water reactors and the arrangement described aims to improve heat transfer between the fuel rods and the coolant. Baffle means extending axially within the channel are provided and disposed relative to the fuel rods so as to restrict flow oscillations occurring within the coolant from being propagated transversely to the axis of the channel. (UK)

  15. Effects of tied ridges and mulch on barley (Hordeum vulgare) rainwater use efficiency and production in Northern Ethiopia

    NARCIS (Netherlands)

    Araya, A.; Stroosnijder, L.

    2010-01-01

    Two alternative in situ area rainwater conservation practices (tied ridging and mulching) were evaluated for four seasons (2004, 2007, 2008 and 2009) at an experimental station in Mekelle, Ethiopia. The objectives were to evaluate the performance of barley as influenced by mulch and tied ridge and

  16. 78 FR 75547 - Prestressed Concrete Steel Rail Tie Wire From Thailand: Preliminary Determination of Sales at Not...

    Science.gov (United States)

    2013-12-12

    ... DEPARTMENT OF COMMERCE International Trade Administration [A-549-829] Prestressed Concrete Steel...'') preliminarily determines that prestressed concrete steel rail tire wire (``PC tie wire'') from Thailand is not... shape, size or alloy element levels; suitable for use as prestressed tendons in concrete railroad ties...

  17. Let the Weakest Link Go! Empirical Explorations on the Relative Importance of Weak and Strong Ties on Social Networking Sites

    Directory of Open Access Journals (Sweden)

    Nicole C. Krämer

    2014-12-01

    Full Text Available Theoretical approaches as well as empirical results in the area of social capital accumulation on social networking sites suggest that weak ties/bridging versus strong ties/bonding social capital should be distinguished and that while bonding social capital is connected to emotional support, bridging social capital entails the provision of information. Additionally, recent studies imply the notion that weak ties/bridging social capital are gaining increasing importance in today’s social media environments. By means of a survey (N = 317 we challenged these presuppositions by assessing the social support functions that are ascribed to three different types of contacts from participants’ network (weak, medium, or strong tie. In contrast to theoretical assumptions, we do not find that weak ties are experienced to supply informational support whereas strong ties first and foremost provide emotional support. Instead we find that within social networking sites, strong ties are perceived to provide both emotional and informational support and weak ties are perceived as less important than recent literature assumes.

  18. The bright-side and dark-side effects of embedded ties in business-to-business innovation

    NARCIS (Netherlands)

    Noordhoff, C.S.; Kyriakopoulos, K.; Moorman, C.; Pauwels, P.; Dellaert, B.

    2011-01-01

    Although the number and importance of joint innovation projects between suppliers and their customers continue to rise, the literature has yet to resolve a key question: Do embedded ties with customers help or hurt supplier innovation? Drawing on both the tie strength and knowledge literatures, the

  19. New Channels, New Possibilities

    DEFF Research Database (Denmark)

    Pieterson, Willem; Ebbers, Wolfgang; Østergaard Madsen, Christian

    2017-01-01

    In this contribution we discuss the characteristics of what we call the fourth generation of public sector service channels: social robots. Based on a review of relevant literature we discuss their characteristics and place into multi-channel models of service delivery. We argue that social robots......-channel models of service delivery. This is especially relevant given the current lack of evaluations of such models, the broad range of channels available, and their different stages of deployment at governments around the world. Nevertheless, social robots offer an potentially very relevant addition...

  20. Calcium Channel Blockers

    Science.gov (United States)

    ... Certain calcium channel blockers interact with grapefruit products. Kaplan NM, et al. Treatment of hypertension: Drug therapy. In: Kaplan's Clinical Hypertension. 11th ed. Philadelphia, Pa.: Wolters Kluwer ...

  1. A channel profile analyser

    International Nuclear Information System (INIS)

    Gobbur, S.G.

    1983-01-01

    It is well understood that due to the wide band noise present in a nuclear analog-to-digital converter, events at the boundaries of adjacent channels are shared. It is a difficult and laborious process to exactly find out the shape of the channels at the boundaries. A simple scheme has been developed for the direct display of channel shape of any type of ADC on a cathode ray oscilliscope display. This has been accomplished by sequentially incrementing the reference voltage of a precision pulse generator by a fraction of a channel and storing ADC data in alternative memory locations of a multichannel pulse height analyser. Alternative channels are needed due to the sharing at the boundaries of channels. In the flat region of the profile alternate memory locations are channels with zero counts and channels with the full scale counts. At the boundaries all memory locations will have counts. The shape of this is a direct display of the channel boundaries. (orig.)

  2. The value of the absent bow tie sign in MRI of bucket-handle tears

    International Nuclear Information System (INIS)

    Watt, Andrew J.B.; Halliday, Tonya; Raby, Nigel

    2000-01-01

    AIM: To assess the accuracy of the absent bow tie sign in diagnosing bucket handle meniscal tears (BHT) of the knee menisci. MATERIALS AND METHODS: During a 3-year period, we correlated the MRI and arthroscopic findings and the presence of the various signs. One hundred and seven knees were reviewed: 74 where either MRI or arthroscopy had identified a BHT and 33 which were either normal (31), or a simple tear was identified (2). All cases were reviewed by a single radiologist with a musculoskeletal interest blinded to the original results. Each was assessed for the presence of (1) a central meniscal fragment, (2) the double posterior cruciate ligament (PCL) sign, (3) the bow tie sign and (4) the contribution of a 3D-volume sequence. RESULTS: Optimal results were obtained using standard sequences and a 3D-volume sequence, giving a sensitivity of 74% and positive predictive value of 89%. The bow tie sign gave a sensitivity of 71% and positive predictive value of 76%, significantly less than previous reports. The 18 BHTs diagnosed by arthroscopy but missed by MRI showed other abnormal findings at MRI and were not reported as normal. CONCLUSION: We were not able to reproduce the previously reported high sensitivity and specificity of the absent bow tie sign. Despite optimization of all factors, the accurate diagnosis of a bucket handle tear remains difficult, and is most reliably made by identifying a central meniscal fragment, rather than relying on secondary signs such as the absent bow tie sign. Watt, A.J.B. (2000)

  3. Development and Testing of a Prototype Grid-Tied Photovoltaic Power System

    Science.gov (United States)

    Eichenberg, Dennis J.

    2009-01-01

    The NASA Glenn Research Center (GRC) has developed and tested a prototype 2 kW DC grid-tied photovoltaic (PV) power system at the Center. The PV system has generated in excess of 6700 kWh since operation commenced in July 2006. The PV system is providing power to the GRC grid for use by all. Operation of the prototype PV system has been completely trouble free. A grid-tied PV power system is connected directly to the utility distribution grid. Facility power can be obtained from the utility system as normal. The PV system is synchronized with the utility system to provide power for the facility, and excess power is provided to the utility. The project transfers space technology to terrestrial use via nontraditional partners. GRC personnel glean valuable experience with PV power systems that are directly applicable to various space power systems, and provide valuable space program test data. PV power systems help to reduce harmful emissions and reduce the Nation s dependence on fossil fuels. Power generated by the PV system reduces the GRC utility demand, and the surplus power aids the community. Present global energy concerns reinforce the need for the development of alternative energy systems. Modern PV panels are readily available, reliable, efficient, and economical with a life expectancy of at least 25 years. Modern electronics has been the enabling technology behind grid-tied power systems, making them safe, reliable, efficient, and economical with a life expectancy of at least 25 years. Based upon the success of the prototype PV system, additional PV power system expansion at GRC is under consideration. The prototype grid-tied PV power system was successfully designed and developed which served to validate the basic principles described, and the theoretical work that was performed. The report concludes that grid-tied photovoltaic power systems are reliable, maintenance free, long life power systems, and are of significant value to NASA and the community.

  4. A linearization of quantum channels

    Science.gov (United States)

    Crowder, Tanner

    2015-06-01

    Because the quantum channels form a compact, convex set, we can express any quantum channel as a convex combination of extremal channels. We give a Euclidean representation for the channels whose inverses are also valid channels; these are a subset of the extreme points. They form a compact, connected Lie group, and we calculate its Lie algebra. Lastly, we calculate a maximal torus for the group and provide a constructive approach to decomposing any invertible channel into a product of elementary channels.

  5. Omni channel fashion shopping

    NARCIS (Netherlands)

    Kemperman, A.D.A.M.; van Delft, L.; Borgers, A.W.J.; Pantano, E.

    2015-01-01

    This chapter gives insight into consumers' online and offline fashion shopping behavior, consumers' omni-channel usage during the shopping process, and consumer fashion shopper segments. Based on a literature review, omni-channel shopping behavior during the shopping process was operationalized.

  6. Channel electron multipliers

    International Nuclear Information System (INIS)

    Seidman, A.; Avrahami, Z.; Sheinfux, B.; Grinberg, J.

    1976-01-01

    A channel electron multiplier is described having a tubular wall coated with a secondary-electron emitting material and including an electric field for accelerating the electrons, the electric field comprising a plurality of low-resistive conductive rings each alternating with a high-resistive insulating ring. The thickness of the low-resistive rings is many times larger than that of the high-resistive rings, being in the order of tens of microns for the low-resistive rings and at least one order of magnitude lower for the high-resistive rings; and the diameter of the channel tubular walls is also many times larger than the thickness of the high-resistive rings. Both single-channel and multiple-channel electron multipliers are described. A very important advantage, particularly in making multiple-channel multipliers, is the simplicity of the procedure that may be used in constructing such multipliers. Other operational advantages are described

  7. Cardiac potassium channel subtypes

    DEFF Research Database (Denmark)

    Schmitt, Nicole; Grunnet, Morten; Olesen, Søren-Peter

    2014-01-01

    About 10 distinct potassium channels in the heart are involved in shaping the action potential. Some of the K(+) channels are primarily responsible for early repolarization, whereas others drive late repolarization and still others are open throughout the cardiac cycle. Three main K(+) channels...... drive the late repolarization of the ventricle with some redundancy, and in atria this repolarization reserve is supplemented by the fairly atrial-specific KV1.5, Kir3, KCa, and K2P channels. The role of the latter two subtypes in atria is currently being clarified, and several findings indicate...... that they could constitute targets for new pharmacological treatment of atrial fibrillation. The interplay between the different K(+) channel subtypes in both atria and ventricle is dynamic, and a significant up- and downregulation occurs in disease states such as atrial fibrillation or heart failure...

  8. Cl- channels in apoptosis

    DEFF Research Database (Denmark)

    Wanitchakool, Podchanart; Ousingsawat, Jiraporn; Sirianant, Lalida

    2016-01-01

    A remarkable feature of apoptosis is the initial massive cell shrinkage, which requires opening of ion channels to allow release of K(+), Cl(-), and organic osmolytes to drive osmotic water movement and cell shrinkage. This article focuses on the role of the Cl(-) channels LRRC8, TMEM16/anoctamin......, and cystic fibrosis transmembrane conductance regulator (CFTR) in cellular apoptosis. LRRC8A-E has been identified as a volume-regulated anion channel expressed in many cell types. It was shown to be required for regulatory and apoptotic volume decrease (RVD, AVD) in cultured cell lines. Its presence also......(-) channels or as regulators of other apoptotic Cl(-) channels, such as LRRC8. CFTR has been known for its proapoptotic effects for some time, and this effect may be based on glutathione release from the cell and increase in cytosolic reactive oxygen species (ROS). Although we find that CFTR is activated...

  9. CHANNEL ESTIMATION TECHNIQUE

    DEFF Research Database (Denmark)

    2015-01-01

    A method includes determining a sequence of first coefficient estimates of a communication channel based on a sequence of pilots arranged according to a known pilot pattern and based on a receive signal, wherein the receive signal is based on the sequence of pilots transmitted over the communicat......A method includes determining a sequence of first coefficient estimates of a communication channel based on a sequence of pilots arranged according to a known pilot pattern and based on a receive signal, wherein the receive signal is based on the sequence of pilots transmitted over...... the communication channel. The method further includes determining a sequence of second coefficient estimates of the communication channel based on a decomposition of the first coefficient estimates in a dictionary matrix and a sparse vector of the second coefficient estimates, the dictionary matrix including...... filter characteristics of at least one known transceiver filter arranged in the communication channel....

  10. Global TIE Observatories: Real Time Observational Astronomy Through a Robotic Telescope Network

    Science.gov (United States)

    Clark, G.; Mayo, L. A.

    2001-12-01

    activities. Hundreds of schools in the US, Australia, Canada, England, and Japan have participated in the TIE program, remotely controlling the 24-inch telescope at the Mount Wilson Observatory from their classrooms. In recent years, several (approximately 20 to date) other telescopes have been, or are in the process of being, outfitted for remote use as TIE affiliates. Global TIE integrates these telescopes seamlessly into one virtual observatory and provides the services required to operate this facility, including a scheduling service, tools for data manipulation, an online proposal review environment, an online "Virtual TIE Student Ap J" for publication of results, and access to related educational materials provided by the TIE community. This presentation describes the Global TIE Observatory data and organizational systems and details the technology, partnerships, operational capabilities, science applications, and learning opportunities that this powerful virtual observatory network will provide.

  11. The weak-ties in advanced business services as a major force of innovation and diffusion; Las Eak-Ties en los servicios avanzados a empresas como factor relevante de la innovacion y su difusion

    Energy Technology Data Exchange (ETDEWEB)

    Almenar i Llongo, V.; Hernandez Sancho, F.; Solar i Marco, V.

    2012-07-01

    This paper tries to expose the role of weak-ties of advanced business services in both mechanisms which generate innovation as well as allow technological diffusion and transfer of innovations (spillovers). Assuming that the latest information generally flows to agents through weak ties, the Weak-Ties Hypothesis (WTH) is an approach that helps to explain the importance of the relations with the environment in the process of innovation and generation of new knowledge and its implementation and dissemination, evaluating the synergy's resulting from cooperation between agents. (Author) 21 refs.

  12. Longitudinal analysis of large social networks: estimating the effect of health traits on changes in friendship ties.

    Science.gov (United States)

    O'Malley, A James; Christakis, Nicholas A

    2011-04-30

    We develop novel mixed effects models to examine the role of health traits on the status of peoples' close friendship nominations in the Framingham Heart Study. The health traits considered are both mutable (body mass index (BMI), smoking, blood pressure, body proportion, muscularity, and depression) and, for comparison, basically immutable (height, birth order, personality type, only child, and handedness); and the traits have varying degrees of observability. We test the hypotheses that existing ties (i.e. close friendship nominations) are more likely to dissolve between people with dissimilar (mutable and observable) health traits whereas new ties are more likely to form between those with similar (mutable and observable) traits while controlling for persons' age, gender, geographic separation, and education. The mixed effects models contain random effects for both the nominator (ego) and nominated (alter) persons in a tie to account for the fact that people were involved in multiple relationships and contributed observations at multiple exams. Results for BMI support the hypotheses that people of similar BMI are less likely to dissolve existing ties and more likely to form ties, while smoker to non-smoker ties were the least likely to dissolve and smoker to smoker ties were the most likely to form. We also validated previously known findings regarding homophily on age and gender, and found evidence that homophily also depends upon geographic separation. Copyright © 2011 John Wiley & Sons, Ltd.

  13. Circulating angiopoietin-2 and soluble Tie-2 in type 2 diabetes mellitus: a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Wagner Ludwig

    2011-06-01

    Full Text Available Abstract Background Type 2 diabetes is associated with increased levels of Angiopoietin-2 (Ang-2 and soluble Tie-2 (sTie-2, but its impact on vascular disease is still unknown. This study aimed to further explore the associations of Ang-2 and sTie-2 with metabolic control and diabetic complications. Methods In a cross-sectional designed study, levels of Ang-2 and sTie-2 as well as their relationships to cardiometabolic parameters were determined in 80 type 2 diabetic subjects (age 65 ± 7 years, female 47.4%. Results After controlling for age and BMI, Ang-2 levels were associated with levels of sTie-2, diastolic blood pressure, plasma insulin, homeostasis model assessment of insulin resistance (HOMA-IR, creatinine, glomerular filtration rate (GFR, and gamma-glutamyl transferase (GGT (all p 1c, fasting plasma glucose and insulin, HOMA-IR, triglyceride, and liver function parameters (all p 1c, insulin levels, and HOMA-IR (p Conclusions Ang-2 is independently associated with levels of GGT while sTie-2 is independently associated with levels of HbA1c, plasma insulin and HOMA-IR in type 2 diabetic subjects. Therefore we suggest that the associations of Ang-2 and sTie-2 with type 2 diabetes are based on different patho-physiological mechanisms.

  14. Religious and Non-religious Activity Engagement as Assets in Promoting Social Ties Throughout University: The Role of Emotion Regulation.

    Science.gov (United States)

    Semplonius, Thalia; Good, Marie; Willoughby, Teena

    2015-08-01

    Emerging adulthood is a time of many changes. For example, one change that occurs for a subset of emerging adults is leaving home and starting university. Importantly, the creation of social ties can aid in promoting positive adjustment during university. This study investigated whether involvement in religious activities promotes social ties among university students directly and/or indirectly through emotion regulation. Importantly, involvement in religious activities may promote self-regulatory skills, and the ability to effectively regulate emotions can aid in navigating social interactions. To rule out potentially important confounding variables, spirituality and involvement in non-religious clubs were statistically controlled in all analyses. The participants included 1,132 university students (70.5 % female) from a university in Ontario, Canada who were surveyed each year over a period of 3 years. The results indicated that involvement in religious activities indirectly predicted more social ties over time through emotion regulation. Spirituality did not predict social ties or emotion regulation. Furthermore, non-religious clubs directly predicted more social ties over time. Thus, although involvement in religious and non-religious activities both predicted more social ties in a university setting over time, the mechanism by which these activities promote social ties differed.

  15. Impact of Cross-Tie Properties on the Modal Behavior of Cable Networks on Cable-Stayed Bridges.

    Science.gov (United States)

    Ahmad, Javaid; Cheng, Shaohong; Ghrib, Faouzi

    2015-01-01

    Dynamic behaviour of cable networks is highly dependent on the installation location, stiffness, and damping of cross-ties. Thus, these are the important design parameters for a cable network. While the effects of the former two on the network response have been investigated to some extent in the past, the impact of cross-tie damping has rarely been addressed. To comprehend our knowledge of mechanics associated with cable networks, in the current study, an analytical model of a cable network will be proposed by taking into account both cross-tie stiffness and damping. In addition, the damping property of main cables in the network will also be considered in the formulation. This would allow exploring not only the effectiveness of a cross-tie design on enhancing the in-plane stiffness of a constituted cable network, but also its energy dissipation capacity. The proposed analytical model will be applied to networks with different configurations. The influence of cross-tie stiffness and damping on the modal response of various types of networks will be investigated by using the corresponding undamped rigid cross-tie network as a reference base. Results will provide valuable information on the selection of cross-tie properties to achieve more effective cable vibration control.

  16. Impact of Cross-Tie Properties on the Modal Behavior of Cable Networks on Cable-Stayed Bridges

    Directory of Open Access Journals (Sweden)

    Javaid Ahmad

    2015-01-01

    Full Text Available Dynamic behaviour of cable networks is highly dependent on the installation location, stiffness, and damping of cross-ties. Thus, these are the important design parameters for a cable network. While the effects of the former two on the network response have been investigated to some extent in the past, the impact of cross-tie damping has rarely been addressed. To comprehend our knowledge of mechanics associated with cable networks, in the current study, an analytical model of a cable network will be proposed by taking into account both cross-tie stiffness and damping. In addition, the damping property of main cables in the network will also be considered in the formulation. This would allow exploring not only the effectiveness of a cross-tie design on enhancing the in-plane stiffness of a constituted cable network, but also its energy dissipation capacity. The proposed analytical model will be applied to networks with different configurations. The influence of cross-tie stiffness and damping on the modal response of various types of networks will be investigated by using the corresponding undamped rigid cross-tie network as a reference base. Results will provide valuable information on the selection of cross-tie properties to achieve more effective cable vibration control.

  17. Coherifying quantum channels

    Science.gov (United States)

    Korzekwa, Kamil; Czachórski, Stanisław; Puchała, Zbigniew; Życzkowski, Karol

    2018-04-01

    Is it always possible to explain random stochastic transitions between states of a finite-dimensional system as arising from the deterministic quantum evolution of the system? If not, then what is the minimal amount of randomness required by quantum theory to explain a given stochastic process? Here, we address this problem by studying possible coherifications of a quantum channel Φ, i.e., we look for channels {{{Φ }}}{ \\mathcal C } that induce the same classical transitions T, but are ‘more coherent’. To quantify the coherence of a channel Φ we measure the coherence of the corresponding Jamiołkowski state J Φ. We show that the classical transition matrix T can be coherified to reversible unitary dynamics if and only if T is unistochastic. Otherwise the Jamiołkowski state {J}{{Φ }}{ \\mathcal C } of the optimally coherified channel is mixed, and the dynamics must necessarily be irreversible. To assess the extent to which an optimal process {{{Φ }}}{ \\mathcal C } is indeterministic we find explicit bounds on the entropy and purity of {J}{{Φ }}{ \\mathcal C }, and relate the latter to the unitarity of {{{Φ }}}{ \\mathcal C }. We also find optimal coherifications for several classes of channels, including all one-qubit channels. Finally, we provide a non-optimal coherification procedure that works for an arbitrary channel Φ and reduces its rank (the minimal number of required Kraus operators) from {d}2 to d.

  18. CANDU channel flow verification

    International Nuclear Information System (INIS)

    Mazalu, N.; Negut, Gh.

    1997-01-01

    The purpose of this evaluation was to obtain accurate information on each channel flow that enables us to assess precisely the level of reactor thermal power and, for reasons of safety, to establish which channel is boiling. In order to assess the channel flow parameters, computer simulations were done with the NUCIRC code and the results were checked by measurements. The complete channel flow measurements were made in the zero power cold condition. In hot conditions there were made flow measurements using the Shut Down System 1 (SDS 1) flow devices from 0.1 % F.P. up to 100 % F.P. The NUCIRC prediction for CANDU channel flows and the measurements by Ultrasonic Flow Meter at zero power cold conditions and SDS 1 flow channel measurements at different reactor power levels showed an acceptable agreement. The 100 % F.P. average errors for channel flow of R, shows that suitable NUCIRC flow assessment can be made. So, it can be done a fair prediction of the reactor power distribution. NUCIRC can predict accurately the onset of boiling and helps to warn at the possible power instabilities at high powers or it can detect the flow blockages. The thermal hydraulic analyst has in NUCIRC a suitable tool to do accurate predictions for the thermal hydraulic parameters for different steady state power levels which subsequently leads to an optimal CANDU reactor operation. (authors)

  19. Analysis of Silver Ink Bow-Tie RFID Tag Antennas Printed on Paper Substrates

    Directory of Open Access Journals (Sweden)

    Sari Merilampi

    2007-01-01

    Full Text Available In this study, polymeric silver inks, paper substrates, and screen printing were used to produce prototype Bow-Tie tags. Because of increasing interest in applying passive UHF-RFID systems in paper industry, the Bow-Tie antenna used in this study was designed to work through paper. The maximum reliable read ranges of the tags were measured thorough stacked paper and also in air. The analysis and functioning of the antenna design are also discussed. All inks and paper substrates were suitable as antenna material and the prototype tag antennas had good reading performance. The maximum reliable read ranges were quite the same as for copper and aluminum tags studied elsewhere. This means that printed UHF tags are competitive solutions for the identification of simple mass products.

  20. Dendrometer bands made easy: using modified cable ties to measure incremental growth of trees

    Science.gov (United States)

    Anemaet, Evelyn R.; Middleton, Beth A.

    2013-01-01

    Dendrometer bands are a useful way to make sequential repeated measurements of tree growth, but traditional dendrometer bands can be expensive, time consuming, and difficult to construct in the field. An alternative to the traditional method of band construction is to adapt commercially available materials. This paper describes how to construct and install dendrometer bands using smooth-edged, stainless steel, cable tie banding and attachable rollerball heads. As a performance comparison, both traditional and cable tie dendrometer bands were installed on baldcypress trees at the National Wetlands Research Center in Lafayette, Louisiana, by both an experienced and a novice worker. Band installation times were recorded, and growth of the trees as estimated by the two band types was measured after approximately one year, demonstrating equivalence of the two methods. This efficient approach to dendrometer band construction can help advance the knowledge of long-term tree growth in ecological studies.

  1. Strengthening Social Ties to Increase Confidence and Self-Esteem Among Sexual and Gender Minority Youth.

    Science.gov (United States)

    Romijnders, Kim A; Wilkerson, J Michael; Crutzen, Rik; Kok, Gerjo; Bauldry, Jessica; Lawler, Sylvia M

    2017-05-01

    Sexual and gender minority (SGM) youth too often live in nonsupportive environments. This study reports the influence of social support from primary and secondary social ties on confidence and self-esteem among participants in Hatch Youth, a drop-in group-level intervention for SGM youth. Each 3-hour Hatch Youth meeting consists of a social, educational, and youth-led support hour. Over 14 weeks, these meetings were randomly observed and individual interviews with participating youth ( n = 12) and staff and volunteers ( n = 12) were conducted; data underwent a content analysis. Participants perceived an increase in confidence and self-esteem through enhanced bonding with family and friends, a sense of belonging, and community empowerment because of their involvement with Hatch Youth, suggesting drop-in centers can strengthen secondary social ties and improve confidence and self-esteem.

  2. Passivity Enhancement of Grid-Tied Converter by Series LC-Filtered Active Damper

    DEFF Research Database (Denmark)

    Bai, Haofeng; Wang, Xiongfei; Loh, Poh Chiang

    2015-01-01

    attention. Also, parasitic capacitance of the grid transmission line brings new challenge for the application of an active damper, which has not been discussed before. In order to fill these gaps, this paper first analyzes the stability of a grid-tied converter with the help of passivity. Based......Series LC-filtered active damper can be used to stabilize the grid-tied voltage source converter in a non-ideal grid. The operation principle of the active damper is to mimic a damping resistance at the resonance frequencies. However, the selection of the damping resistance has not received much...... on the passivity-based-stability analysis, a damping resistance selection method is proposed. Then, an admittance shaping method is developed to ensure the system stability in the presence of parasitic capacitance of the transmission line. Finally, experimental results are provided to show the validity...

  3. Decentralized automatic generation control of interconnected power systems incorporating asynchronous tie-lines.

    Science.gov (United States)

    Ibraheem; Hasan, Naimul; Hussein, Arkan Ahmed

    2014-01-01

    This Paper presents the design of decentralized automatic generation controller for an interconnected power system using PID, Genetic Algorithm (GA) and Particle Swarm Optimization (PSO). The designed controllers are tested on identical two-area interconnected power systems consisting of thermal power plants. The area interconnections between two areas are considered as (i) AC tie-line only (ii) Asynchronous tie-line. The dynamic response analysis is carried out for 1% load perturbation. The performance of the intelligent controllers based on GA and PSO has been compared with the conventional PID controller. The investigations of the system dynamic responses reveal that PSO has the better dynamic response result as compared with PID and GA controller for both type of area interconnection.

  4. An Exploratory Examination of Social Ties and Crime in Mobile Home Communities

    Directory of Open Access Journals (Sweden)

    William P. McCarty

    2013-11-01

    Full Text Available Guided by the systemic model of social disorganization, the purpose of this study was to explore the nature of social ties in mobile home communities and examine how that relates to rates of violent and property crime. Interviews with a small sample of mobile home residents, owners, and managers in Omaha, Nebraska, indicate a wide spectrum of communities, from those characterized by an atomized population to those with strong social ties. Fear of crime, ethnically heterogeneous populations, and lax management were cited by respondents as factors that undermined relationships. Proactive management and a desire to help neighbors were cited by respondents as factors that helped strengthen relationships. Violent and property crime rates for the mobile home communities were largely consistent with the interview data, providing support for the importance of social networks and a systemic model of social disorganization. The implications of these findings for research and policy are also explored.

  5. Can Social Ties be Harmful? Examining the Spread of Suicide in Early Adulthood.

    Science.gov (United States)

    Mueller, Anna S; Abrutyn, Seth; Stockton, Cynthia

    2015-06-01

    Durkheim posited that social relationships protect individuals against suicide; however, substantial research demonstrates that suicide can spread through the very ties Durkheim theorized as protective. With this study, we use Waves I, III, and IV of the National Longitudinal Study of Adolescent Health, to investigate whether young adults' suicide attempts and thoughts are in part products of exposure to suicidal behaviors via their social relationships. We find that young adults who have had family members or friends attempt suicide are more likely to report suicide ideation or even suicide attempts, over both the short and long run. This finding is robust to many important controls for risk and protective factors for suicide. Our findings have implications for the sociology of suicide, not the least of which, is that social ties have the power to harm in addition to the power to protect.

  6. Reconfigurable virtual electrowetting channels.

    Science.gov (United States)

    Banerjee, Ananda; Kreit, Eric; Liu, Yuguang; Heikenfeld, Jason; Papautsky, Ian

    2012-02-21

    Lab-on-a-chip systems rely on several microfluidic paradigms. The first uses a fixed layout of continuous microfluidic channels. Such lab-on-a-chip systems are almost always application specific and far from a true "laboratory." The second involves electrowetting droplet movement (digital microfluidics), and allows two-dimensional computer control of fluidic transport and mixing. The merging of the two paradigms in the form of programmable electrowetting channels takes advantage of both the "continuous" functionality of rigid channels based on which a large number of applications have been developed to date and the "programmable" functionality of digital microfluidics that permits electrical control of on-chip functions. In this work, we demonstrate for the first time programmable formation of virtual microfluidic channels and their continuous operation with pressure driven flows using an electrowetting platform. Experimental, theoretical, and numerical analyses of virtual channel formation with biologically relevant electrolyte solutions and electrically-programmable reconfiguration are presented. We demonstrate that the "wall-less" virtual channels can be formed reliably and rapidly, with propagation rates of 3.5-3.8 mm s(-1). Pressure driven transport in these virtual channels at flow rates up to 100 μL min(-1) is achievable without distortion of the channel shape. We further demonstrate that these virtual channels can be switched on-demand between multiple inputs and outputs. Ultimately, we envision a platform that would provide rapid prototyping of microfluidic concepts and would be capable of a vast library of functions and benefitting applications from clinical diagnostics in resource-limited environments to rapid system prototyping to high throughput pharmaceutical applications.

  7. Selection based on the size of the black tie of the great tit may be reversed in urban habitats.

    Science.gov (United States)

    Senar, Juan Carlos; Conroy, Michael J; Quesada, Javier; Mateos-Gonzalez, Fernando

    2014-07-01

    A standard approach to model how selection shapes phenotypic traits is the analysis of capture-recapture data relating trait variation to survival. Divergent selection, however, has never been analyzed by the capture-recapture approach. Most reported examples of differences between urban and nonurban animals reflect behavioral plasticity rather than divergent selection. The aim of this paper was to use a capture-recapture approach to test the hypothesis that divergent selection can also drive local adaptation in urban habitats. We focused on the size of the black breast stripe (i.e., tie width) of the great tit (Parus major), a sexual ornament used in mate choice. Urban great tits display smaller tie sizes than forest birds. Because tie size is mostly genetically determined, it could potentially respond to selection. We analyzed capture/recapture data of male great tits in Barcelona city (N = 171) and in a nearby (7 km) forest (N = 324) from 1992 to 2008 using MARK. When modelling recapture rate, we found it to be strongly influenced by tie width, so that both for urban and forest habitats, birds with smaller ties were more trap-shy and more cautious than their larger tied counterparts. When modelling survival, we found that survival prospects in forest great tits increased the larger their tie width (i.e., directional positive selection), but the reverse was found for urban birds, with individuals displaying smaller ties showing higher survival (i.e., directional negative selection). As melanin-based tie size seems to be related to personality, and both are heritable, results may be explained by cautious personalities being favored in urban environments. More importantly, our results show that divergent selection can be an important mechanism in local adaptation to urban habitats and that capture-recapture is a powerful tool to test it.

  8. Phosphorylation of Threonine 794 on Tie1 by Rac1/PAK1 Reveals a Novel Angiogenesis Regulatory Pathway.

    Directory of Open Access Journals (Sweden)

    Jessica L Reinardy

    Full Text Available The endothelial receptor tyrosine kinase (RTK Tie1 was discovered over 20 years ago, yet its precise function and mode of action remain enigmatic. To shed light on Tie1's role in endothelial cell biology, we investigated a potential threonine phosphorylation site within the juxtamembrane domain of Tie1. Expression of a non-phosphorylatable mutant of this site (T794A in zebrafish (Danio rerio significantly disrupted vascular development, resulting in fish with stunted and poorly branched intersomitic vessels. Similarly, T794A-expressing human umbilical vein endothelial cells formed significantly shorter tubes with fewer branches in three-dimensional Matrigel cultures. However, mutation of T794 did not alter Tie1 or Tie2 tyrosine phosphorylation or downstream signaling in any detectable way, suggesting that T794 phosphorylation may regulate a Tie1 function independent of its RTK properties. Although T794 is within a consensus Akt phosphorylation site, we were unable to identify a physiological activator of Akt that could induce T794 phosphorylation, suggesting that Akt is not the physiological Tie1-T794 kinase. However, the small GTPase Ras-related C3 botulinum toxin substrate 1 (Rac1, which is required for angiogenesis and capillary morphogenesis, was found to associate with phospho-T794 but not the non-phosphorylatable T794A mutant. Pharmacological activation of Rac1 induced downstream activation of p21-activated kinase (PAK1 and T794 phosphorylation in vitro, and inhibition of PAK1 abrogated T794 phosphorylation. Our results provide the first demonstration of a signaling pathway mediated by Tie1 in endothelial cells, and they suggest that a novel feedback loop involving Rac1/PAK1 mediated phosphorylation of Tie1 on T794 is required for proper angiogenesis.

  9. Evaluation channel performance in multichannel environments

    NARCIS (Netherlands)

    Gensler, S.; Dekimpe, M.; Skiera, B.

    2007-01-01

    Evaluating channel performance is crucial for actively managing multiple sales channels, and requires understanding the customers' channel preferences. Two key components of channel performance are (i) the existing customers' intrinsic loyalty to a particular channel and (ii) the channel's ability

  10. Risk assessment in gas and oil pipelines based on the fuzzy Bow-tie technique

    OpenAIRE

    P. Heyrani; A. Baghaei

    2016-01-01

    Introduction: Nowadays, gas and oil account for 60 percent of world energy resources. Transporting crude oil and its products are accomplished through a number of ways among which pipelines are of the utmost significance. Considering the extent of pipelines in installation and residential areas and also high potential for damage, the safety of these pipes and application of risk management principles have undeniable importance. Bow-tie risk assessment method is one of the ways to determine sa...

  11. Comparison radiographic and automated ultrasonic inspection of pipeline tie-in welds

    International Nuclear Information System (INIS)

    Connelly, T.; Gross, B.

    2007-01-01

    In recent years the use of automated ultrasonic inspection (AUT) for pipeline girth welds has seen rapid growth and is now used almost exclusively for all gas metal arc welding (GMAW) girth weld inspection. The following paper reviews some of the major features of ultrasonic inspection by comparison to conventional Film Radiography (RT) and reviews the use of ultrasonic inspection for pipeline and tie-in welds. (author)

  12. GNSS-SLR satellite co-location for the estimate of local ties

    Science.gov (United States)

    Bruni, Sara; Zerbini, Susanna; Errico, Maddalena; Santi, Efisio

    2013-04-01

    The current realization of the International Terrestrial Reference Frame (ITRF) is based on four different space-geodetic techniques, so that the benefits brought by each observing system to the definition of the frame can compensate for the drawbacks of the others and technique-specific systematic errors might be identified. The strategy used to combine the observations from the different techniques is then of prominent importance for the realization of a precise and stable reference frame. This study concentrates, in particular, on the combination of Satellite Laser Ranging (SLR) and Global Navigation Satellite System (GNSS) observations by exploiting satellite co-locations. This innovative approach is based on the fact that laser tracking of GNSS satellites, carrying on board laser reflector arrays, allows for the combination of optical and microwave signals in the determination of the spacecraft orbit. Besides, the use of satellite co-locations differs quite significantly from the traditional combination method in which each single technique solution is carried out autonomously and is interrelated in a second step. One of the benefits of the approach adopted in this study is that it allows for an independent validation of the local tie, i.e. of the vector connecting the SLR and GNSS reference points in a multi-techniques station. Typically, local ties are expressed by a single value, measured with ground-based geodetic techniques and taken as constant. In principle, however, local ties might show time variations likely caused by the different monumentation characteristics of the GNSS antennas with respect to those of a SLR system. This study evaluates the possibility of using the satellite co-location approach to generate local-ties time series by means of observations available for a selected network of ILRS stations. The data analyzed in this study were acquired as part of the NASA's Earth Science Data Systems and are archived and distributed by the Crustal

  13. Toward an integrated ice core chronology using relative and orbital tie-points

    Science.gov (United States)

    Bazin, L.; Landais, A.; Lemieux-Dudon, B.; Toyé Mahamadou Kele, H.; Blunier, T.; Capron, E.; Chappellaz, J.; Fischer, H.; Leuenberger, M.; Lipenkov, V.; Loutre, M.-F.; Martinerie, P.; Parrenin, F.; Prié, F.; Raynaud, D.; Veres, D.; Wolff, E.

    2012-04-01

    Precise ice cores chronologies are essential to better understand the mechanisms linking climate change to orbital and greenhouse gases concentration forcing. A tool for ice core dating (DATICE [developed by Lemieux-Dudon et al., 2010] permits to generate a common time-scale integrating relative and absolute dating constraints on different ice cores, using an inverse method. Nevertheless, this method has only been applied for a 4-ice cores scenario and for the 0-50 kyr time period. Here, we present the bases for an extension of this work back to 800 ka using (1) a compilation of published and new relative and orbital tie-points obtained from measurements of air trapped in ice cores and (2) an adaptation of the DATICE inputs to 5 ice cores for the last 800 ka. We first present new measurements of δ18Oatm and δO2/N2 on the Talos Dome and EPICA Dome C (EDC) ice cores with a particular focus on Marine Isotopic Stages (MIS) 5, and 11. Then, we show two tie-points compilations. The first one is based on new and published CH4 and δ18Oatm measurements on 5 ice cores (NorthGRIP, EPICA Dronning Maud Land, EDC, Talos Dome and Vostok) in order to produce a table of relative gas tie-points over the last 400 ka. The second one is based on new and published records of δO2/N2, δ18Oatm and air content to provide a table of orbital tie-points over the last 800 ka. Finally, we integrate the different dating constraints presented above in the DATICE tool adapted to 5 ice cores to cover the last 800 ka and show how these constraints compare with the established gas chronologies of each ice core.

  14. Differential Disclosure Across Social Network Ties Among Women Living with HIV

    OpenAIRE

    Rice, Eric; Comulada, Scott; Green, Sara; Arnold, Elizabeth Mayfield; Rotheram-Borus, Mary Jane

    2009-01-01

    Women?s disclosure of their HIV serostatus across social network ties was examined in a sample of women living in Los Angeles (n?=?234), using multivariate random intercept logistic regressions. Women with disclosure-averse attitudes were less likely to disclose, while women with higher CD4+ counts were significantly more likely to disclose, regardless of relationship type. Relative to all other types of relationships, spouses/romantic partners were greater than four times more likely to be t...

  15. Performance analysis of new type grid-tied inverter-Aalborg Inverter

    DEFF Research Database (Denmark)

    Wu, Weimin; Wang, Zhen; Ji, Junhao

    2014-01-01

    Aalborg Inverter is a grid-tied DC/AC inverter. In order to optimize the design, its power losses are analyzed in detail, combined with a description of the single-phase operating principle and the modulation strategy. A 2 kW / 220 V experimental prototype is constructed to verify the theoretical...... analysis. It is concluded that a minimize inductance in the power loop does help the inverter to achieve the high efficiency with the good dynamic performance....

  16. Effect of summer grazing on welfare of dairy cows reared in mountain tie-stall barns

    Directory of Open Access Journals (Sweden)

    Simonetta Dovier

    2010-09-01

    Full Text Available Traditional mountain farms have an important economic, social and environmental role. The Alps management system for dairy cows consists of animals kept indoors from autumn to spring, mostly in tie-stalls, and moved to mountain pasture in summer. The aim of our study was to assess the effect of mountain summer grazing on the welfare of dairy cows housed in tie-stall barns. Twenty-four farms were considered. In twelve of them, animals were reared in tie-stalls and moved to mountain pasture for three months in summer; they were visited three times: (i four weeks before grazing during the indoor period in the stall; (ii about three weeks after the start of grazing; and (iii in the stall, in autumn, at least three weeks after returning from grazing. The other twelve farms kept the animals in tie-stalls all year; they were visited once in autumn. Data were collected following a protocol that considers animal-based measures and structure information on the basis of Quality Welfare Consortium® indications. Data allowed the calculation of both the Animal Needs Index score (ANI 35L and an overall assessment of the cows’ welfare obtained from three general aspects: housing, animal’s physical condition, and animal’s behaviour. Summer grazing had a significant positive effect on injuries, lameness and animal’s rising duration but a negative effect on faeces consistency. Moreover, a reduction of tongue playing was observed. The ANI 35L and the overall assessment did not show significant differences linked to summer grazing, which tended to have a positive but temporary effect on animal behaviour.

  17. Competitive position, managerial ties, and profitability of foreign firms in China: an interactive perspective

    OpenAIRE

    Julie Juan Li; Kevin Zheng Zhou; Alan T Shao

    2009-01-01

    Despite the prominence of the competitive strategy perspective, it remains unclear whether foreign firms entering China can still adopt a differentiation or low-cost position to achieve superior performance, given the unique market and institutional environments in China. Alternatively, should foreign firms follow conventional wisdom and actively build managerial ties with government officials and business community to enhance their performance? This study develops and tests an interactive pe...

  18. Developing an Objective Structured Assessment of Technical Skills for Laparoscopic Suturing and Intracorporeal Knot Tying.

    Science.gov (United States)

    Chang, Olivia H; King, Louise P; Modest, Anna M; Hur, Hye-Chun

    2016-01-01

    To develop a teaching and assessment tool for laparoscopic suturing and intracorporeal knot tying. We designed an Objective Structured Assessment of Technical Skills (OSATS) tool that includes a procedure-specific checklist (PSC) and global rating scale (GRS) to assess laparoscopic suturing and intracorporeal knot-tying performance. Obstetrics and Gynecology residents at our institution were videotaped while performing a laparoscopic suturing and intracorporeal knot-tying task at a surgical simulation workshop. A total of 2 expert reviewers assessed resident performance using the OSATS tool during live performance and 1 month later using the videotaped recordings. OSATS scores were analyzed using the Wilcoxon rank-sum test. Data are presented as median scores (interquartile range [IQR]). Intrarater and interrater reliabilities were assessed using a Spearman correlation and are presented as an r correlation coefficient and p value. An r ≥ 0.8 was considered as a high correlation. After testing, we received feedback from residents and faculty to improve the OSATS tool as part of an iterative design process. In all, 14 of 21 residents (66.7%) completed the study, with 9 junior residents and 5 senior residents. Junior residents had a lower score on the PSC than senior residents did; however, this was not statistically significant (median = 6.0 [IQR: 4.0-10.0] and median = 13.0 [IQR: 10.0-13.0]; p = 0.09). There was excellent intrarater reliability with our OSATS tool (for PSC component, r = 0.88 for Rater 1 and 0.93 for Rater 2, both p assessment and teaching tool for laparoscopic suturing and intracorporeal knot-tying skills. Overall, good intrarater reliability was demonstrated, suggesting that this tool may be useful for longitudinal assessment of surgical skills. Copyright © 2015 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

  19. Investigation of nanoeffect on wear of details and ties of oilfield devices

    International Nuclear Information System (INIS)

    Shahbazov, E.G.; Shafiyev, Sh.Sh.

    2010-01-01

    The investigations have been carried out at SOCAR on the study of nanoparticles effect on the corrosion of metallic surfaces. It was defined that corrosion rate decreases as a result.It is stated in the article that nanotechnology applications have prospects for protection of details and ties of oilfield equipment. It is necessary to work out special programs for this case. The authors had an attempt to form the main aspects of such programs.

  20. Distinct RNA transcriptome patterns are potentially associated with angiogenesis in Tie2-expressing monocytes.

    Science.gov (United States)

    Wang, Xinjing; Dai, Zhiyuan; Wu, Xiaoli; Wang, Kai; Wang, Xipeng

    2016-04-10

    Tie2-expressing Monocytes (TEMs) were previously identified as a novel subset of monocytes and were believed to have prominent pro-angiogenesis activities in human tumors. While the molecular mechanism of the angiogenesis promoting capacity of TEMs remains unclear. RNA transcriptome pattern, including non-coding RNAs as microRNA (miRNA) and long non-coding RNA (lncRNA), plays important role in cell differentiation and functions. However, little is known about the transcriptome patterns of TEMs, including those non-coding RNAs. We explore the transcriptome of TEMs and the matched monocytes that do not express Tie2 (Tie2(-)monocytes) isolated from peripheral blood of healthy adults employing the Agilent Human miRNA(8*60K,Design ID: 046064)microarray and the Agilent lncRNA Gene Expression(4*180K, Design ID: 042818)microarray. A total of 141 mRNAs, 142 lncRNAs and 75 miRNAs were found dysregulated in TEMs compared to Tie2(-)monocytes. TEMs have the distinct RNA transcriptome patterns according to the Hierarchical clustering and then the gene expression patterns were confirmed by quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR). Functional annotation by Gene Ontology (GO) analyses showed that the up-regulated mRNAs in TEMs were associated to blood vessel remodeling and positive regulation of epithelial cell proliferation, and the up-regulated insulin like growth factor 1(IGF1) mRNA was involved in both pathways. For functional analysis of those dysregulated non-coding RNAs, target genes of the miRNAs were predicted and cis/trans-regulation analysis of the lncRNAs were performed. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Tying Knots

    DEFF Research Database (Denmark)

    Bødker, Susanne; Dindler, Christian; Iversen, Ole Sejer

    2017-01-01

    dispersed within these networks. To illustrate and discuss the process of participatory infrastructuring we use a case study from an educational context. This particular project contains a diverse set of design activities at many organizational levels revolving around technology, decision-making, competence...... of the literature on infrastructuring, participatory design, and activity theory, and leads to a revised understanding of, for example, learning and conflicts in participatory infrastructuring....

  2. Direct channel problems and phenomena

    International Nuclear Information System (INIS)

    Cutkosky, R.E.

    1975-01-01

    Direct channel problems and phenomena are considered covering the need for precision hadron spectroscopy, the data base for precision hadron spectroscopy, some relations between direct-channel and cross-channel effects, and spin rotation phenomena

  3. Risk analysis of urban gas pipeline network based on improved bow-tie model

    Science.gov (United States)

    Hao, M. J.; You, Q. J.; Yue, Z.

    2017-11-01

    Gas pipeline network is a major hazard source in urban areas. In the event of an accident, there could be grave consequences. In order to understand more clearly the causes and consequences of gas pipeline network accidents, and to develop prevention and mitigation measures, the author puts forward the application of improved bow-tie model to analyze risks of urban gas pipeline network. The improved bow-tie model analyzes accident causes from four aspects: human, materials, environment and management; it also analyzes the consequences from four aspects: casualty, property loss, environment and society. Then it quantifies the causes and consequences. Risk identification, risk analysis, risk assessment, risk control, and risk management will be clearly shown in the model figures. Then it can suggest prevention and mitigation measures accordingly to help reduce accident rate of gas pipeline network. The results show that the whole process of an accident can be visually investigated using the bow-tie model. It can also provide reasons for and predict consequences of an unfortunate event. It is of great significance in order to analyze leakage failure of gas pipeline network.

  4. One Step Solution to the Local Tie Vectors of GNSS/SLR in ITRF

    Directory of Open Access Journals (Sweden)

    MA Xiaping

    2018-01-01

    Full Text Available This paper proposes a one-step solution of local tie vectors,the solution takes RP (Reference Point and axes offsets of SLR telescope as unknown parameters,GNSS baselines network and conventional terrestrial observation (horizontal,vertical angle and distance are combined in ITRF (International Terrestrial Reference Frame,and multiply constraint conditions are established between RP and observation marks and two axes offsets.Local tie vectors and related covariance matrices of the 3 co-located sites in Beijing,Kunming,Xi'an of CMONOC (Crustal Movement Observation Network of China are solved with the proposed one step solution.The results show that the RMS (root mean square error of local tie vectors is less than 2.0 mm.Besides,the differences are less than 2.0 mm compared with the traditional step by step solution,and the offsets and corresponding RMS between the horizontal axis and vertical axis are 3.8 mm,0.7 mm,3.6 mm and 1.3 mm,1.2 mm,1.3 mm,respectively.

  5. Tissue reactions induced by nylon cable tie used to clamp ovarian pedicles

    Directory of Open Access Journals (Sweden)

    Luiz Fernando Moraes Moreira

    2018-03-01

    Full Text Available The aim of this study was to evaluate the tissue reactions induced by nylon cable tie by using macroscopic and histological evaluations. Forty-five clinically healthy crossbreed female dogs, 31.11 ± 14.26 months old and with a body weight of 11.26 ± 4.7 kg, underwent ovariohysterectomy using a minimally invasive procedure. The dogs were randomly divided into three groups of 15 animals each and were evaluated preoperatively, and at 30 (G1, 60 (G2 and 90 days (G3 after surgery. The histological examination of the pedicles containing the nylon cable ties, collected from five animals in each group, showed a chronic inflammatory reaction with the presence of macrophages, giant cells and fibroplasia on the 30th postoperative day. Well-organized connective tissue and presence of lymphocytes and polymorphonuclear leukocytes were seen on the 60th postoperative day, and mature connective tissue and presence of macrophages and lymphocytes were seen at 90 days. Nylon cable ties induce an inflammatory reaction, which should be considered due to the risk of interference with surrounding structures.

  6. Relational benefits and quality of relation – towards understanding of the ties between science and business

    Directory of Open Access Journals (Sweden)

    Małgorzata Grzegorczyk

    2016-06-01

    Full Text Available The goal of this article is to answer the question in what way relational marketing and in particular, the concept of relational benefits, as well as quality of relation may influence the transfer of knowledge and technologies from universities to business. Another goal is to highlight significant, future directions of research in this area. Integration of the theory of relational marketing and technology transfer may create a new framework for fuller understanding of the ties between science and business. Research in this area may contribute to the expansion and development of the theory of relational marketing, which until now was limited to the analysis of relations within a single sector. The results of conducted research show that ties characterized by high relational engagement are common, recognized by both academic and business environment as precious and play an important role in stimulating innovations. The quality of relations and relational benefits may play an important role in building long-term ties between universities and the industry. Integration of behavioural theories with the theory of technology transfer may contribute to a better understanding of the behaviour of particular participants of the transfer on the individual level.

  7. A Simplified Control Method for Tie-Line Power of DC Micro-Grid

    Directory of Open Access Journals (Sweden)

    Yanbo Che

    2018-04-01

    Full Text Available Compared with the AC micro-grid, the DC micro-grid has low energy loss and no issues of frequency stability, which makes it more accessible for distributed energy. Thus, the DC micro-grid has good potential for development. A variety of renewable energy is included in the DC micro-grid, which is easily affected by the environment, causing fluctuation of the DC voltage. For grid-connected DC micro-grid with droop control strategy, the tie-line power is affected by fluctuations in the DC voltage, which sets higher requirements for coordinated control of the DC micro-grid. This paper presents a simplified control method to maintain a constant tie-line power that is suitable for the DC micro-grid with the droop control strategy. By coordinating the designs of the droop control characteristics of generators, energy storage units and grid-connected inverter, a dead band is introduced to the droop control to improve the system performance. The tie-line power in the steady state is constant. When a large disturbance occurs, the AC power grid can provide power support to the micro-grid in time. The simulation example verifies the effectiveness of the proposed control strategy.

  8. Family Ties and Young Fathers’ Engagement in Cape Town, South Africa

    Science.gov (United States)

    Clark, Shelley; Cotton, Cassandra; Marteleto, Leticia J.

    2015-01-01

    Young South African fathers are often engaged in their children’s lives even if they do not live together. Using longitudinal data on children (n = 1,209) from the Cape Town area, the authors show that although only 26% of young fathers live with their children, 66% of nonresidential fathers maintain regular contact, and 61% provide financial support. The father–child relationship, however, is embedded in broader family ties. The type of father–mother relationship is strongly associated with whether fathers coreside with their children, but not with fathers’ contact with nonresidential children. Close mother and maternal grandmother bonds reduce the likelihood that fathers live with their children, whereas close ties between fathers and paternal grandmothers increase the chance that fathers visit nonresidential children. Family ties do not affect fathers’ financial contributions, which are driven by men’s current economic situation. These findings illustrate that father–child relationships are best understood in the context of interacting family systems. PMID:25774066

  9. Understanding the process of social network evolution: Online-offline integrated analysis of social tie formation.

    Science.gov (United States)

    Kwak, Doyeon; Kim, Wonjoon

    2017-01-01

    It is important to consider the interweaving nature of online and offline social networks when we examine social network evolution. However, it is difficult to find any research that examines the process of social tie formation from an integrated perspective. In our study, we quantitatively measure offline interactions and examine the corresponding evolution of online social network in order to understand the significance of interrelationship between online and offline social factors in generating social ties. We analyze the radio signal strength indicator sensor data from a series of social events to understand offline interactions among the participants and measure the structural attributes of their existing online Facebook social networks. By monitoring the changes in their online social networks before and after offline interactions in a series of social events, we verify that the ability to develop an offline interaction into an online friendship is tied to the number of social connections that participants previously had, while the presence of shared mutual friends between a pair of participants disrupts potential new connections within the pre-designed offline social events. Thus, while our integrative approach enables us to confirm the theory of preferential attachment in the process of network formation, the common neighbor theory is not supported. Our dual-dimensional network analysis allows us to observe the actual process of social network evolution rather than to make predictions based on the assumption of self-organizing networks.

  10. Understanding the process of social network evolution: Online-offline integrated analysis of social tie formation.

    Directory of Open Access Journals (Sweden)

    Doyeon Kwak

    Full Text Available It is important to consider the interweaving nature of online and offline social networks when we examine social network evolution. However, it is difficult to find any research that examines the process of social tie formation from an integrated perspective. In our study, we quantitatively measure offline interactions and examine the corresponding evolution of online social network in order to understand the significance of interrelationship between online and offline social factors in generating social ties. We analyze the radio signal strength indicator sensor data from a series of social events to understand offline interactions among the participants and measure the structural attributes of their existing online Facebook social networks. By monitoring the changes in their online social networks before and after offline interactions in a series of social events, we verify that the ability to develop an offline interaction into an online friendship is tied to the number of social connections that participants previously had, while the presence of shared mutual friends between a pair of participants disrupts potential new connections within the pre-designed offline social events. Thus, while our integrative approach enables us to confirm the theory of preferential attachment in the process of network formation, the common neighbor theory is not supported. Our dual-dimensional network analysis allows us to observe the actual process of social network evolution rather than to make predictions based on the assumption of self-organizing networks.

  11. Improvement and Application of the Softened Strut-and-Tie Model

    Science.gov (United States)

    Fan, Guoxi; Wang, Debin; Diao, Yuhong; Shang, Huaishuai; Tang, Xiaocheng; Sun, Hai

    2017-11-01

    Previous experimental researches indicate that reinforced concrete beam-column joints play an important role in the mechanical properties of moment resisting frame structures, so as to require proper design. The aims of this paper are to predict the joint carrying capacity and cracks development theoretically. Thus, a rational model needs to be developed. Based on the former considerations, the softened strut-and-tie model is selected to be introduced and analyzed. Four adjustments including modifications of the depth of the diagonal strut, the inclination angle of diagonal compression strut, the smeared stress of mild steel bars embedded in concrete, as well as the softening coefficient are made. After that, the carrying capacity of beam-column joint and cracks development are predicted using the improved softened strut-and-tie model. Based on the test results, it is not difficult to find that the improved softened strut-and-tie model can be used to predict the joint carrying capacity and cracks development with sufficient accuracy.

  12. Suggesting alternatives for reinforced concrete deep beams by reinforcing struts and ties

    Directory of Open Access Journals (Sweden)

    Saleem Abdul-Razzaq Khattab

    2017-01-01

    Full Text Available This paper studied reinforcing struts and ties in deep beams based on the Strut-and-Tie Model (STM of ACI 318M-14. The study contained testing 9 simply supported specimens, divided into 3 groups. The difference between the groups was the loading type which was 2-concentrated forces, 1-concentrated force and uniformly distributed load. Each group contained three specimens; the first specimens in each group were conventional deep beams as references which had a length of 1400 mm, a height of 400 mm and a width of 150 mm. The second specimens were the same as references in dimensions, but with removing shoulders. In addition, only the paths of struts & ties of STM were reinforced in the second specimens as compression and tension members, respectively. The third specimens were the frames that took their dimensions from STM of ACI 318M-14. From the experimental work, it is found that the proposed frames were good alternatives for the references despite the small loss in ultimate capacity. However, these proposed frames already carried loads greater than the factored design loads of STM. In comparison with the references, these proposed frames provided 41-51% reduction in weight, 4-27% reduction in cost besides providing front side area about 46-55%.

  13. A Tie-Over Dressing Using a Silicone Tube to Graft Deep Wounds

    Directory of Open Access Journals (Sweden)

    Cem Inan Bektas

    2013-11-01

    Full Text Available BackgroundThe most common cause of skin graft failure is the collection of blood or serous fluid underneath the graft. In our study, we describe the use of silicone tube for tie-over dressing to secure the skin graft margins with the aim of decreasing loss of the skin graft, particularly in grafting of deep wounds.MethodsBetween March 2008 and July 2011, we used this technique in 17 patients with skin defects with depths ranging from 3.5 to 8 mm (mean, 5.5 mm. First, the skin graft was sutured with 3/0 silk suture material from its corners. Then, a silicone round drain tube was sutured with 3/0 absorbable polyglactin 910 over the margins of the graft. Finally, long silk threads were tied over the bolus dressing, and the tie-over dressing was completed in the usual fashion.ResultsThe mean follow-up was 7 months (range, 2-10 months in the outpatient clinic. Graft loss on the graft margins due to hematoma or seroma was not developed. The results of adhesion between the graft and wound bed peripherally was excellent.ConclusionsIn our study, we suggest that use of a silicone tube for additional pressure on the edges of skin grafts in case of reconstruction of deep skin defects.

  14. Intermediate Monocytes but Not TIE2-Expressing Monocytes Are a Sensitive Diagnostic Indicator for Colorectal Cancer

    Science.gov (United States)

    Schauer, Dominic; Starlinger, Patrick; Reiter, Christian; Jahn, Nikolaus; Zajc, Philipp; Buchberger, Elisabeth; Bachleitner-Hofmann, Thomas; Bergmann, Michael; Stift, Anton; Gruenberger, Thomas; Brostjan, Christine

    2012-01-01

    We have conducted the first study to determine the diagnostic potential of the CD14++CD16+ intermediate monocytes as compared to the pro-angiogenic subset of CD14++CD16+TIE2+ TIE2-expressing monocytes (TEMs) in cancer. These monocyte populations were investigated by flow cytometry in healthy volunteers (N = 32) and in colorectal carcinoma patients with localized (N = 24) or metastatic (N = 37) disease. We further determined blood levels of cytokines associated with monocyte regulation. The results revealed the intermediate monocyte subset to be significantly elevated in colorectal cancer patients and to show the highest frequencies in localized disease. Multivariate regression analysis identified intermediate monocytes as a significant independent variable in cancer prediction. With a cut-off value at 0.37% (intermediate monocytes of total leukocytes) the diagnostic sensitivity and specificity ranged at 69% and 81%, respectively. In contrast, TEM levels were elevated in localized cancer but did not differ significantly between groups and none of the cytokines correlated with monocyte subpopulations. Of interest, in vitro analyses supported the observation that intermediate monocytes were more potently induced by primary as opposed to metastatic cancer cells which may relate to the immunosuppressive milieu established in the advanced stage of metastatic disease. In conclusion, intermediate monocytes as compared to TIE2-expressing monocytes are a more sensitive diagnostic indicator of colorectal cancer. PMID:22973451

  15. Intermediate monocytes but not TIE2-expressing monocytes are a sensitive diagnostic indicator for colorectal cancer.

    Directory of Open Access Journals (Sweden)

    Dominic Schauer

    Full Text Available We have conducted the first study to determine the diagnostic potential of the CD14++CD16+ intermediate monocytes as compared to the pro-angiogenic subset of CD14++CD16+TIE2+ TIE2-expressing monocytes (TEMs in cancer. These monocyte populations were investigated by flow cytometry in healthy volunteers (N = 32 and in colorectal carcinoma patients with localized (N = 24 or metastatic (N = 37 disease. We further determined blood levels of cytokines associated with monocyte regulation. The results revealed the intermediate monocyte subset to be significantly elevated in colorectal cancer patients and to show the highest frequencies in localized disease. Multivariate regression analysis identified intermediate monocytes as a significant independent variable in cancer prediction. With a cut-off value at 0.37% (intermediate monocytes of total leukocytes the diagnostic sensitivity and specificity ranged at 69% and 81%, respectively. In contrast, TEM levels were elevated in localized cancer but did not differ significantly between groups and none of the cytokines correlated with monocyte subpopulations. Of interest, in vitro analyses supported the observation that intermediate monocytes were more potently induced by primary as opposed to metastatic cancer cells which may relate to the immunosuppressive milieu established in the advanced stage of metastatic disease. In conclusion, intermediate monocytes as compared to TIE2-expressing monocytes are a more sensitive diagnostic indicator of colorectal cancer.

  16. Finite element analyses of continuous filament ties for masonry applications : final report for the Arquin Corporation.

    Energy Technology Data Exchange (ETDEWEB)

    Quinones, Armando, Sr. (Arquin Corporation, La Luz, NM); Bibeau, Tiffany A.; Ho, Clifford Kuofei

    2008-08-01

    Finite-element analyses were performed to simulate the response of a hypothetical vertical masonry wall subject to different lateral loads with and without continuous horizontal filament ties laid between rows of concrete blocks. A static loading analysis and cost comparison were also performed to evaluate optimal materials and designs for the spacers affixed to the filaments. Results showed that polypropylene, ABS, and polyethylene (high density) were suitable materials for the spacers based on performance and cost, and the short T-spacer design was optimal based on its performance and functionality. Simulations of vertical walls subject to static loads representing 100 mph winds (0.2 psi) and a seismic event (0.66 psi) showed that the simulated walls performed similarly and adequately when subject to these loads with and without the ties. Additional simulations and tests are required to assess the performance of actual walls with and without the ties under greater loads and more realistic conditions (e.g., cracks, non-linear response).

  17. Many channel spectrum unfolding

    International Nuclear Information System (INIS)

    Najzer, M.; Glumac, B.; Pauko, M.

    1980-01-01

    The principle of the ITER unfolding code as used for the many channel spectrum unfolding is described. Its unfolding ability is tested on seven typical neutron spectra. The effect of the initial spectrum approximation upon the solution is discussed

  18. Channelized Streams in Iowa

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — This draft dataset consists of all ditches or channelized pieces of stream that could be identified using three input datasets; namely the1:24,000 National...

  19. Coding for optical channels

    CERN Document Server

    Djordjevic, Ivan; Vasic, Bane

    2010-01-01

    This unique book provides a coherent and comprehensive introduction to the fundamentals of optical communications, signal processing and coding for optical channels. It is the first to integrate the fundamentals of coding theory and optical communication.

  20. Sensing with Ion Channels

    CERN Document Server

    Martinac, Boris

    2008-01-01

    All living cells are able to detect and translate environmental stimuli into biologically meaningful signals. Sensations of touch, hearing, sight, taste, smell or pain are essential to the survival of all living organisms. The importance of sensory input for the existence of life thus justifies the effort made to understand its molecular origins. Sensing with Ion Channels focuses on ion channels as key molecules enabling biological systems to sense and process the physical and chemical stimuli that act upon cells in their living environment. Its aim is to serve as a reference to ion channel specialists and as a source of new information to non specialists who want to learn about the structural and functional diversity of ion channels and their role in sensory physiology.

  1. Calcium channel blocker poisoning

    Directory of Open Access Journals (Sweden)

    Miran Brvar

    2005-04-01

    Full Text Available Background: Calcium channel blockers act at L-type calcium channels in cardiac and vascular smooth muscles by preventing calcium influx into cells with resultant decrease in vascular tone and cardiac inotropy, chronotropy and dromotropy. Poisoning with calcium channel blockers results in reduced cardiac output, bradycardia, atrioventricular block, hypotension and shock. The findings of hypotension and bradycardia should suggest poisoning with calcium channel blockers.Conclusions: Treatment includes immediate gastric lavage and whole-bowel irrigation in case of ingestion of sustainedrelease products. All patients should receive an activated charcoal orally. Specific treatment includes calcium, glucagone and insulin, which proved especially useful in shocked patients. Supportive care including the use of catecholamines is not always effective. In the setting of failure of pharmacological therapy transvenous pacing, balloon pump and cardiopulmonary by-pass may be necessary.

  2. TRP channels: an overview

    DEFF Research Database (Denmark)

    Pedersen, Stine Falsig; Owsianik, Grzegorz; Nilius, Bernd

    2005-01-01

    The TRP ("transient receptor potential") family of ion channels now comprises more than 30 cation channels, most of which are permeable for Ca2+, and some also for Mg2+. On the basis of sequence homology, the TRP family can be divided in seven main subfamilies: the TRPC ('Canonical') family......, the TRPV ('Vanilloid') family, the TRPM ('Melastatin') family, the TRPP ('Polycystin') family, the TRPML ('Mucolipin') family, the TRPA ('Ankyrin') family, and the TRPN ('NOMPC') family. The cloning and characterization of members of this cation channel family has exploded during recent years, leading...... to a plethora of data on the roles of TRPs in a variety of tissues and species, including mammals, insects, and yeast. The present review summarizes the most pertinent recent evidence regarding the structural and functional properties of TRP channels, focusing on the regulation and physiology of mammalian TRPs....

  3. Authentication over Noisy Channels

    OpenAIRE

    Lai, Lifeng; Gamal, Hesham El; Poor, H. Vincent

    2008-01-01

    In this work, message authentication over noisy channels is studied. The model developed in this paper is the authentication theory counterpart of Wyner's wiretap channel model. Two types of opponent attacks, namely impersonation attacks and substitution attacks, are investigated for both single message and multiple message authentication scenarios. For each scenario, information theoretic lower and upper bounds on the opponent's success probability are derived. Remarkably, in both scenarios,...

  4. Channelling versus inversion

    DEFF Research Database (Denmark)

    Gale, A.S.; Surlyk, Finn; Anderskouv, Kresten

    2013-01-01

    Evidence from regional stratigraphical patterns in Santonian−Campanian chalk is used to infer the presence of a very broad channel system (5 km across) with a depth of at least 50 m, running NNW−SSE across the eastern Isle of Wight; only the western part of the channel wall and fill is exposed. W......−Campanian chalks in the eastern Isle of Wight, involving penecontemporaneous tectonic inversion of the underlying basement structure, are rejected....

  5. Stream Channel Stability.

    Science.gov (United States)

    1981-04-01

    Cycles of wetting and drying are also t ,v itiue swelling and shrinkage of the soil. S 11ied blocks or peds of soil fabric ,,ks. id downslope soil creep ...hydrographs of water and sediment at the point in question. By feeding the output from the hydrology-transport model into the finite element model...the banks as undercut banks fail. Channel irregularities such as seepage zones, cattle crossings, overbank drainage, buried channels, organic deposits

  6. Channeling and dynamic chaos

    Energy Technology Data Exchange (ETDEWEB)

    Bolotin, IU L; Gonchar, V IU; Truten, V I; Shulga, N F

    1986-01-01

    It is shown that axial channeling of relativistic electrons can give rise to the effect of dynamic chaos which involves essentially chaotic motion of a particle in the channel. The conditions leading to the effect of dynamic chaos and the manifestations of this effect in physical processes associated with the passage of particles through a crystal are examined using a silicon crystal as an example. 7 references.

  7. The blind faith deep water horizontal pipeline tie-in project

    Energy Technology Data Exchange (ETDEWEB)

    Charalambides, John Nicos [Oceaneering International, Inc., Houston, TX (United States)

    2009-12-19

    This presentation will concentrate on the design challenges, experience and learning from the SIT and offshore installation of two deepwater pipeline tie-ins using first-of-its-kind subsea technology and installation methodologies on the 'Blind Faith' project. The Blind Faith Subsea Tie-Ins join the Blind Faith oil and gas pipelines with the Canyon Chief gas pipeline and the Mountaineer oil pipeline in 5100 feet of water. Both of the Blind Faith oil and gas pipelines are terminated with conventional PLEMs providing a horizontal connector for the tie-in and a vertical connector for a future tie-in connection point. The connectors are ROV operable/installable clamp style connectors. The method of joining to the Canyon Chief oil and gas pipelines and the type of jumper employed are unique to the tie-in. An ROV operable / installable mechanical pipe end connector connects the bare ends of the Canyon Chief and Mountaineer pipelines. The mechanical pipe end connector is fitted with an integral clamp connector hub and rests on an ROV installed mud mat. After installation of the mechanical connector, metrology was performed to create a neutral state horizontal jumper for joining the mechanical connector hub and the Blind Faith PLEM. The neutral state horizontal jumper is a compliant 'Z-Bend' design. During installation the jumper was elastically pre-deformed using a bowstring system. Pre-deformation of the jumper provided installation clearances and facilitated the neutral stress state after installation. Once landed the jumper bowstring was relaxed, allowing the jumper to expand to fit between the hubs. After expansion and make-up, the clamp connectors were tightened via an ROV operated hydraulic torque wrench. A seal test verified the integrity of the connections. After installation the jumper remains in a minimal residual stress state atypical of most horizontal jumpers. The horizontal jumper was chosen over the vertical jumper because it provides a

  8. Development and Testing of the Glenn Research Center Visitor's Center Grid-Tied Photovoltaic Power System

    Science.gov (United States)

    Eichenberg, Dennis J.

    2009-01-01

    The NASA Glenn Research Center (GRC) has developed, installed, and tested a 12 kW DC grid-tied photovoltaic (PV) power system at the GRC Visitor s Center. This system utilizes a unique ballast type roof mount for installing the photovoltaic panels on the roof of the Visitor s Center with no alterations or penetrations to the roof. The PV system has generated in excess of 15000 kWh since operation commenced in August 2008. The PV system is providing power to the GRC grid for use by all. Operation of the GRC Visitor s Center PV system has been completely trouble free. A grid-tied PV power system is connected directly to the utility distribution grid. Facility power can be obtained from the utility system as normal. The PV system is synchronized with the utility system to provide power for the facility, and excess power is provided to the utility. The project transfers space technology to terrestrial use via nontraditional partners. GRC personnel glean valuable experience with PV power systems that are directly applicable to various space power systems, and provides valuable space program test data. PV power systems help to reduce harmful emissions and reduce the Nation s dependence on fossil fuels. Power generated by the PV system reduces the GRC utility demand, and the surplus power aids the community. Present global energy concerns reinforce the need for the development of alternative energy systems. Modern PV panels are readily available, reliable, efficient, and economical with a life expectancy of at least 25 years. Modern electronics has been the enabling technology behind grid-tied power systems, making them safe, reliable, efficient, and economical with a life expectancy of at least 25 years. Based upon the success of the GRC Visitor s Center PV system, additional PV power system expansion at GRC is under consideration. The GRC Visitor s Center grid-tied PV power system was successfully designed and developed which served to validate the basic principles

  9. Design of a Glenn Research Center Solar Field Grid-Tied Photovoltaic Power System

    Science.gov (United States)

    Eichenberg, Dennis J.

    2009-01-01

    The NASA Glenn Research Center (GRC) designed, developed, and installed, a 37.5 kW DC photovoltaic (PV) Solar Field in the GRC West Area in the 1970s for the purpose of testing PV panels for various space and terrestrial applications. The PV panels are arranged to provide a nominal 120 VDC. The GRC Solar Field has been extremely successful in meeting its mission. The PV panels and the supporting electrical systems are all near their end of life. GRC has designed a 72 kW DC grid-tied PV power system to replace the existing GRC West Area Solar Field. The 72 kW DC grid-tied PV power system will provide DC solar power for GRC PV testing applications, and provide AC facility power for all times that research power is not required. A grid-tied system is connected directly to the utility distribution grid. Facility power can be obtained from the utility system as normal. The PV system is synchronized with the utility system to provide power for the facility, and excess power is provided to the utility for use by all. The project transfers space technology to terrestrial use via nontraditional partners. GRC personnel glean valuable experience with PV power systems that are directly applicable to various space power systems, and provide valuable space program test data. PV power systems help to reduce harmful emissions and reduce the Nation s dependence on fossil fuels. Power generated by the PV system reduces the GRC utility demand, and the surplus power aids the community. Present global energy concerns reinforce the need for the development of alternative energy systems. Modern PV panels are readily available, reliable, efficient, and economical with a life expectancy of at least 25 years. Modern electronics has been the enabling technology behind grid-tied power systems, making them safe, reliable, efficient, and economical with a life expectancy of at least 25 years. The report concludes that the GRC West Area grid-tied PV power system design is viable for a reliable

  10. 360° virtual reality video for the acquisition of knot tying skills: A randomised controlled trial.

    Science.gov (United States)

    Yoganathan, S; Finch, D A; Parkin, E; Pollard, J

    2018-04-10

    360° virtual reality (VR) video is an exciting and evolving field. Current technology promotes a totally immersive, 3-dimensional (3D), 360° experience anywhere in the world using simply a smart phone and virtual reality headset. The potential for its application in the field of surgical education is enormous. The aim of this study was to determine knot tying skills taught with a 360-degree VR video compared to conventional 2D video teaching. This trial was a prospective, randomised controlled study. 40 foundation year doctors (first year postgraduate) were randomised to either the 360-degree VR video (n = 20) or 2D video teaching (n = 20). Participants were given 15 min to watch their allocated video. Ability to tie a single handed reef knot was then assessed against a marking criteria developed for the Royal College of Surgeons, England, (RCSeng) Basic Surgical Skills (BSS) course, by a blinded assessor competent in knot tying. Each candidate then underwent further teaching using Peyton's four step model. Knot tying technique was then re-assessed. Knot tying scores were significantly better in the VR video teaching arm when compared with conventional (median knot score 5.0 vs 4.0 p = 0.04). When used in combination with face to face skills teaching this difference persisted (median knot score 9.5 vs 9.0 p = 0.01). More people in the VR arm constructed a complete reef knot than in the 2D arm following face to face teaching (17/20 vs 12/20). No difference between the groups existed in the time taken to construct a reef knot following video and teaching (median time 31.0s vs 30.5s p = 0.89). This study shows there is significant merit in the application of 360-degree VR video technology in surgical training, both as an independent teaching aid and when used as an adjunct to traditional face to face teaching. Copyright © 2018 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.

  11. Dairy cows welfare quality in tie-stall housing system with or without access to exercise

    Science.gov (United States)

    2013-01-01

    Background Tie-stall housing of dairy cows is used extensively worldwide, despite of the welfare concerns regarding the restriction of voluntary movement and limitation of expression of the cows’ natural behaviour. The aim of this study was to compare the welfare quality of dairy cows kept in two types of tie-stall housing systems: with regular outdoor exercise and without access to exercise. In addition, the study investigated the relationship between different welfare measures of dairy cows kept in tie-stalls. Methods 3,192 lactating cows were assessed using the Welfare Quality® assessment protocol for cattle in 80 commercial dairy farms, half of the farms providing outdoor access for the animals to exercise. The descriptive statistical indicators were determined for the assessed measures and for the welfare criteria and principle scores. The data obtained in the two housing types were compared and the correlation coefficients were calculated between the different welfare measures. Results The significant differences found between the two housing systems for the majority of the animal based measures indicate the positive effect of exercise on the welfare of tethered cows. Many of the animal welfare parameters correlated with each other. For the farms allowing the cows’ turnout in a paddock, pasture or both, the mean scores for the welfare criteria and principles were higher than for the farms with permanent tethering of the cows, except the criteria absence of prolonged hunger and expression of social behaviours. The lowest scores were obtained for the criterion positive emotional state, in both housing systems. With regard to the overall classification, none of the farms were considered excellent. In the not classified category were only farms with all-year-round tethering of the animals and in the enhanced category only farms where the cows had outdoor access. Conclusions The welfare quality of the investigated dairy cows was significantly better in the

  12. Course on Ionic Channels

    CERN Document Server

    1986-01-01

    This book is based on a series of lectures for a course on ionic channels held in Santiago, Chile, on November 17-20, 1984. It is intended as a tutorial guide on the properties, function, modulation, and reconstitution of ionic channels, and it should be accessible to graduate students taking their first steps in this field. In the presentation there has been a deliberate emphasis on the spe­ cific methodologies used toward the understanding of the workings and function of channels. Thus, in the first section, we learn to "read" single­ channel records: how to interpret them in the theoretical frame of kinetic models, which information can be extracted from gating currents in re­ lation to the closing and opening processes, and how ion transport through an open channel can be explained in terms of fluctuating energy barriers. The importance of assessing unequivocally the origin and purity of mem­ brane preparations and the use of membrane vesicles and optical tech­ niques in the stUGY of ionic channels a...

  13. Expression of VEGF receptors VEFGR-1 and VEGFR-2, angiopoietin receptors Tie-1 and Tie-2 in chorionic villi tree during early pregnancy.

    Directory of Open Access Journals (Sweden)

    Ramazan Demir

    2010-02-01

    Full Text Available The aim of this study was to determine the expression of VEGF and its receptors in placentas from normal pregnancies between 22 days p.c. and 48 days p.c. of very early pregnancy. Placental tissues carried out from 19 pregnant women were examined. Immunohistochemical technique, electron microscopy were employed to evaluate the factors expression. In the new developing mesenchymal villi and immature intermediate villi VEGF and its receptors VEGFR-1 and VEGFR-2 immunoreactivity was detected in all the placental components, while in the stem villi and in the chorionic plate with large vessels only in some components. In the mesenchymal villi and immature intermediate villi VEGFR-1 and -2, and angiopoietin receptors Tie-1 and -2 immunoreactivity was dominantly observed in the heamangiogenic cells and cells cords, whereas the matured villi showed immunoreactivity only in other components. The ultrastructural findings were higher in respect to the all of the early pregnancy days. The placental samples from all of pregnancies, showed the VEGF and its receptors in optimal expression levels, whereas the angiopoietin receptors Tie-1 and -2 showed a higher expression levels in respect to other study factors. The receptors protein levels increased from the early days to the advanced days of gestation, but this alteration was not significant. The intensity of the immunolabeling for these proteins were not significant compared to to each other of gestatin days were examined. These findings demonstrated that a dysregulation of the placental expression of the VEGF and its receptors related to the different degrees of the gestational periods. Probably, this event may be related to complete vasculugenesis and angiogenesis in placental villi.

  14. Minilaparoscopic varicocelectomy with preservation of testicular artery and lymphatic vessels by using intracorporeal knot-tying technique: five-year experience.

    Science.gov (United States)

    Chung, Shiu-Dong; Wu, Chia-Chang; Lin, Victor Chia-Hsiang; Ho, Chen-Hsun; Yang, Stephen Shei Dei; Tsai, Yao-Chou

    2011-08-01

    In this study we present our experience using minilaparoscopic intracorporeal knot tying to ligate internal spermatic veins (ISV) while sparing the spermatic artery and lymphatics. Minilaparoscopic varicocelectomies were performed in 87 patients between January 2004 and January 2009. All varicoceles were detected clinically according to the World Health Organization (WHO) classification and confirmed by scrotal color Doppler ultrasonography. The surgical indications were scrotal symptoms in 71, infertility in 16, and both conditions in 2. Three 3.5 mm minilaparoscopic ports were used for the operation. The ISVs were dissected and then ligated with intracorporeal knot-tying. The testicular artery and lymphatic vessels were carefully preserved to minimize procedure-related complications. Unilateral laparoscopic varicocelectomy was performed in 21 (24.2%) patients and bilateral in 66 (75.8%). Mean operative time was 71.1 ± 29.2 and 46.8 ± 12.6 min for bilateral and unilateral varicocelectomies, respectively. All patients were discharged within 24 h after surgery. Neither immediate major nor late procedure-related complications were noted. Of the 71 patients with scrotal symptoms, the symptoms completely subsided in 55 (77.5%) and partially subsided in 10 (14.1%). Only one (1.2%) recurrent varicocele was detected within a mean follow-up of 21 months (range = 3-42). Neither hydrocele formation nor testicular atrophy was found during the follow-up period. Our 5-year experience revealed that minilaparoscopic varicocelectomy with sparing of artery and lymphatic vessels could safely and effectively ligate all spermatic veins and preserve spermatic arteries and lymphatic channels without leading to a high varicocele persistence or recurrence.

  15. USE OF ZEOLITE FOR REMOVING AMMONIA AND AMMONIA-CAUSED TOXCITY IN MARINE TOXICITY IDENTIFCATION EVALUATIONS (TIES)

    Science.gov (United States)

    Ammonia occurs in marine waters including effluents, receiving waters, and sediment interstitial waters. At sufficiently high concentrations, ammonia can be toxic to aquatic species. Toxicity identification evaluation (TIE) methods provide researchers with tools for identifyi...

  16. Problematic Alcohol Use and Problem Gambling: Associations to Structural and Functional aspects of Social Ties in a Finnish Population Sample

    Directory of Open Access Journals (Sweden)

    Nordmyr Johanna

    2016-09-01

    Full Text Available AIMS – This study aims to explore associations between structural and functional aspects of social networks and relationships (here labelled social ties among individuals exhibiting problematic alcohol use and problem gambling, respectively.

  17. Creative benefits from well-connected leaders: leader social network ties as facilitators of employee radical creativity.

    Science.gov (United States)

    Venkataramani, Vijaya; Richter, Andreas W; Clarke, Ronald

    2014-09-01

    Employee radical creativity critically depends on substantive informational resources from others across the wider organization. We propose that the social network ties of employees' immediate leaders assume a central role in garnering these resources, thereby fostering their employees' radical creativity both independent of and interactively with employees' own network ties. Drawing on data from 214 employees working in 30 teams of a public technology and environmental services organization, we find that team leaders' betweenness centrality in the idea network within their teams as well as among their peer leaders provides creative benefits beyond employees' own internal and external ties. Further, employees' and leaders' ties within and external to the team interactively predict employee radical creativity. Implications for theory and practice are discussed. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  18. Family ties and health cross-nationally: the contextualizing role of familistic culture and public pension spending in Europe.

    Science.gov (United States)

    Mair, Christine A

    2013-11-01

    Although previous research theorizes that cross-national variation in the relationship between family ties and health is due to nation-level differences in culture and policy/economics, no study has examined this theorization empirically. Using data from the Survey of Health, Ageing, and Retirement in Europe (SHARE) and the Organization for Economic Co-operation and Development (OECD), this study uses multilevel modeling to analyze individual-, nation-, and cross-level effects for 30,291 older adults in 14 nations. Family ties to spouses/partners and parents are associated with better health, but ties to coresident children are associated with poorer health in certain contexts. Familistic culture and public pension spending have a weak but statistically significant moderating effect on the relationship between intergenerational family ties and health. This article underscores the complexity of family and highlights the need for continued theorization and measurement at the nation level to promote older adults' health in diverse contexts.

  19. Ion channelling in diamond

    International Nuclear Information System (INIS)

    Derry, T.E.

    1978-06-01

    Diamond is one of the most extreme cases from a channelling point of view, having the smallest thermal vibration amplitude and the lowest atomic number of commonly-encountered crystals. These are the two parameters most important for determining channelling behaviour. It is of consiberable interest therefore to see how well the theories explaining and predicting the channeling properties of other substance, succeed with diamond. Natural diamond, although the best available form for these experiments, is rather variable in its physical properties. Part of the project was devoted to considering and solving the problem of obtaining reproducible results representative of the ideal crystal. Channelling studies were performed on several good crystals, using the Rutherford backscattering method. Critical angles for proton channelling were measured for incident energies from 0.6 to 4.5 MeV, in the three most open axes and three most open planes of the diamond structure, and for α-particle channelling at 0.7 and 1.0 MeV (He + ) in the same axes and planes. For 1.0 MeV protons, the crystal temperature was varied from 20 degrees Celsius to 700 degrees Celsius. The results are presented as curves of backscattered yield versus angle in the region of each axis or plane, and summarised in the form of tables and graphs. Generally the critical angles, axial minimum yields, and temperature dependence are well predicted by the accepted theories. The most valuable overall conclusion is that the mean thermal vibration amplitude of the atoms in a crytical determines the critical approach distance to the channel walls at which an ion can remain channelled, even when this distance is much smaller than the Thomas-Fermi screening distance of the atomic potential, as is the case in diamond. A brief study was made of the radiation damage caused by α-particle bombardment, via its effect on the channelling phenomenon. It was possible to hold damage down to negligible levels during the

  20. Optical Communications Channel Combiner

    Science.gov (United States)

    Quirk, Kevin J.; Quirk, Kevin J.; Nguyen, Danh H.; Nguyen, Huy

    2012-01-01

    NASA has identified deep-space optical communications links as an integral part of a unified space communication network in order to provide data rates in excess of 100 Mb/s. The distances and limited power inherent in a deep-space optical downlink necessitate the use of photon-counting detectors and a power-efficient modulation such as pulse position modulation (PPM). For the output of each photodetector, whether from a separate telescope or a portion of the detection area, a communication receiver estimates a log-likelihood ratio for each PPM slot. To realize the full effective aperture of these receivers, their outputs must be combined prior to information decoding. A channel combiner was developed to synchronize the log-likelihood ratio (LLR) sequences of multiple receivers, and then combines these into a single LLR sequence for information decoding. The channel combiner synchronizes the LLR sequences of up to three receivers and then combines these into a single LLR sequence for output. The channel combiner has three channel inputs, each of which takes as input a sequence of four-bit LLRs for each PPM slot in a codeword via a XAUI 10 Gb/s quad optical fiber interface. The cross-correlation between the channels LLR time series are calculated and used to synchronize the sequences prior to combining. The output of the channel combiner is a sequence of four-bit LLRs for each PPM slot in a codeword via a XAUI 10 Gb/s quad optical fiber interface. The unit is controlled through a 1 Gb/s Ethernet UDP/IP interface. A deep-space optical communication link has not yet been demonstrated. This ground-station channel combiner was developed to demonstrate this capability and is unique in its ability to process such a signal.

  1. Assessment of the possible contribution of space ties on-board GNSS satellites to the terrestrial reference frame

    Science.gov (United States)

    Bruni, Sara; Rebischung, Paul; Zerbini, Susanna; Altamimi, Zuheir; Errico, Maddalena; Santi, Efisio

    2018-04-01

    The realization of the international terrestrial reference frame (ITRF) is currently based on the data provided by four space geodetic techniques. The accuracy of the different technique-dependent materializations of the frame physical parameters (origin and scale) varies according to the nature of the relevant observables and to the impact of technique-specific errors. A reliable computation of the ITRF requires combining the different inputs, so that the strengths of each technique can compensate for the weaknesses of the others. This combination, however, can only be performed providing some additional information which allows tying together the independent technique networks. At present, the links used for that purpose are topometric surveys (local/terrestrial ties) available at ITRF sites hosting instruments of different techniques. In principle, a possible alternative could be offered by spacecrafts accommodating the positioning payloads of multiple geodetic techniques realizing their co-location in orbit (space ties). In this paper, the GNSS-SLR space ties on-board GPS and GLONASS satellites are thoroughly examined in the framework of global reference frame computations. The investigation focuses on the quality of the realized physical frame parameters. According to the achieved results, the space ties on-board GNSS satellites cannot, at present, substitute terrestrial ties in the computation of the ITRF. The study is completed by a series of synthetic simulations investigating the impact that substantial improvements in the volume and quality of SLR observations to GNSS satellites would have on the precision of the GNSS frame parameters.

  2. Effect of Tower Shadow and Wind Shear in a Wind Farm on AC Tie-Line Power Oscillations of Interconnected Power Systems

    DEFF Research Database (Denmark)

    Tan, Jin; Hu, Weihao; Wang, Xiaoru

    2013-01-01

    This paper describes a frequency domain approach for evaluating the impact of tower shadow and wind shear effects (TSWS) on tie-line power oscillations. A simplified frequency domain model of an interconnected power system with a wind farm is developed. The transfer function, which relates the tie......-line power variation to the mechanical power variation of a wind turbine, and the expression of the maximum magnitude of tie-line power oscillations are derived to identify the resonant condition and evaluate the potential risk. The effects of the parameters on the resonant magnitude of the tie-line power...... are also discussed. The frequency domain analysis reveals that TSWS can excite large tie-line power oscillations if the frequency of TSWS approaches the tie-line resonant frequency, especially in the case that the wind farm is integrated into a relatively small grid and the tie-line of the interconnected...

  3. Channel Choice: A Literature Review

    DEFF Research Database (Denmark)

    Østergaard Madsen, Christian; Kræmmergaard, Pernille

    2015-01-01

    The channel choice branch of e-government studies citizens’ and businesses’ choice of channels for interacting with government, and how government organizations can integrate channels and migrate users towards the most cost-efficient channels. In spite of the valuable contributions offered...

  4. Channel Identification Machines

    Directory of Open Access Journals (Sweden)

    Aurel A. Lazar

    2012-01-01

    Full Text Available We present a formal methodology for identifying a channel in a system consisting of a communication channel in cascade with an asynchronous sampler. The channel is modeled as a multidimensional filter, while models of asynchronous samplers are taken from neuroscience and communications and include integrate-and-fire neurons, asynchronous sigma/delta modulators and general oscillators in cascade with zero-crossing detectors. We devise channel identification algorithms that recover a projection of the filter(s onto a space of input signals loss-free for both scalar and vector-valued test signals. The test signals are modeled as elements of a reproducing kernel Hilbert space (RKHS with a Dirichlet kernel. Under appropriate limiting conditions on the bandwidth and the order of the test signal space, the filter projection converges to the impulse response of the filter. We show that our results hold for a wide class of RKHSs, including the space of finite-energy bandlimited signals. We also extend our channel identification results to noisy circuits.

  5. Channel identification machines.

    Science.gov (United States)

    Lazar, Aurel A; Slutskiy, Yevgeniy B

    2012-01-01

    We present a formal methodology for identifying a channel in a system consisting of a communication channel in cascade with an asynchronous sampler. The channel is modeled as a multidimensional filter, while models of asynchronous samplers are taken from neuroscience and communications and include integrate-and-fire neurons, asynchronous sigma/delta modulators and general oscillators in cascade with zero-crossing detectors. We devise channel identification algorithms that recover a projection of the filter(s) onto a space of input signals loss-free for both scalar and vector-valued test signals. The test signals are modeled as elements of a reproducing kernel Hilbert space (RKHS) with a Dirichlet kernel. Under appropriate limiting conditions on the bandwidth and the order of the test signal space, the filter projection converges to the impulse response of the filter. We show that our results hold for a wide class of RKHSs, including the space of finite-energy bandlimited signals. We also extend our channel identification results to noisy circuits.

  6. Cryogenic microwave channelized receiver

    International Nuclear Information System (INIS)

    Rauscher, C.; Pond, J.M.; Tait, G.B.

    1996-01-01

    The channelized receiver being presented demonstrates the use of high temperature superconductor technology in a microwave system setting where superconductor, microwave-monolithic-integrated-circuit, and hybrid-integrated-circuit components are united in one package and cooled to liquid-nitrogen temperatures. The receiver consists of a superconducting X-band four-channel demultiplexer with 100-MHz-wide channels, four commercial monolithically integrated mixers, and four custom-designed hybrid-circuit detectors containing heterostructure ramp diodes. The composite receiver unit has been integrated into the payload of the second-phase NRL high temperature superconductor space experiment (HTSSE-II). Prior to payload assembly, the response characteristics of the receiver were measured as functions of frequency, temperature, and drive levels. The article describes the circuitry, discusses the key issues related to design and implementation, and summarizes the experimental results

  7. Chaos in quantum channels

    Energy Technology Data Exchange (ETDEWEB)

    Hosur, Pavan; Qi, Xiao-Liang [Department of Physics, Stanford University,476 Lomita Mall, Stanford, California 94305 (United States); Roberts, Daniel A. [Center for Theoretical Physics and Department of Physics, Massachusetts Institute of Technology,77 Massachusetts Ave, Cambridge, Massachusetts 02139 (United States); Yoshida, Beni [Perimeter Institute for Theoretical Physics,31 Caroline Street North, Waterloo, Ontario N2L 2Y5 (Canada); Walter Burke Institute for Theoretical Physics, California Institute of Technology,1200 E California Blvd, Pasadena CA 91125 (United States)

    2016-02-01

    We study chaos and scrambling in unitary channels by considering their entanglement properties as states. Using out-of-time-order correlation functions to diagnose chaos, we characterize the ability of a channel to process quantum information. We show that the generic decay of such correlators implies that any input subsystem must have near vanishing mutual information with almost all partitions of the output. Additionally, we propose the negativity of the tripartite information of the channel as a general diagnostic of scrambling. This measures the delocalization of information and is closely related to the decay of out-of-time-order correlators. We back up our results with numerics in two non-integrable models and analytic results in a perfect tensor network model of chaotic time evolution. These results show that the butterfly effect in quantum systems implies the information-theoretic definition of scrambling.

  8. Distribution Channels Conflict and Management

    OpenAIRE

    Kiran, Dr Vasanth; Majumdar, Dr Mousumi; Kishore, Dr Krishna

    2012-01-01

    Relationships in distribution channels tend to be long-term oriented and members of the channel rely on each other to jointly realize their goals by serving buyers. Despite the channels focus on serving buyers, conflicts often arise between channel members because of each members self-interest. When conflicts arise, the perceptions of a channel member based on normative, rational/instrumental, or emotional reasoning will influence relational norms like trust and commitment that characterize t...

  9. How Social Ties Influence Consumer: Evidence from Event-Related Potentials.

    Directory of Open Access Journals (Sweden)

    Jing Luan

    Full Text Available A considerable amount of marketing research has reported that consumers are more saliently influenced by friends (strong social ties than by acquaintances and strangers (weak social ties. To shed light on the neural and psychological processes underlying such phenomenon, in this study we designed an amended S1-S2 paradigm (product-[reviewer-review] that is based on realistic consumer purchase experiences. After incoming all given information (product, reviewer, review, participants were required to state their purchase intentions. The neurocognitive and emotional processes related to friend and stranger stimuli were delineated to suggest how social ties influence consumers during their shopping processes. Larger P2 (fronto-central scalp areas and P3 (central and posterior-parietal scalp areas components under stranger condition were elicited successfully. These findings demonstrate that the cognitive and emotional processing of friend and stranger stimuli occurs at stages of neural activity, and can be indicated by the P2 and P3 components. Electrophysiological data also support the hypothesis that different neural and emotional processing magnitude and strength underlie friend and stranger effect in the context of consumer purchase. During this process, the perception of stimuli evoked P2, subsequently emotional processing and attention modulation were activated and indicated by P2 and P3. The friend dominated phenomenon can be interpreted as the result of distinctive neurocognitive and emotional processing magnitude, which suggests that psychological and emotional factors can guide consumer decision making. This study consolidates that event related potential (ERP methodology is likely to be a more sensitive method for investigating consumer behaviors. From the perspectives of management and marketing, our findings show that the P2 and P3 components can be employed as an indicator to probe the influential factors of consumer purchase

  10. Personalized Video Feedback and Repeated Task Practice Improve Laparoscopic Knot-Tying Skills: Two Controlled Trials.

    Science.gov (United States)

    Abbott, Eduardo F; Thompson, Whitney; Pandian, T K; Zendejas, Benjamin; Farley, David R; Cook, David A

    2017-11-01

    Compare the effect of personalized feedback (PF) vs. task demonstration (TD), both delivered via video, on laparoscopic knot-tying skills and perceived workload; and evaluate the effect of repeated practice. General surgery interns and research fellows completed four repetitions of a simulated laparoscopic knot-tying task at one-month intervals. Midway between repetitions, participants received via e-mail either a TD video (demonstration by an expert) or a PF video (video of their own performance with voiceover from a blinded senior surgeon). Each participant received at least one video per format, with sequence randomly assigned. Outcomes included performance scores and NASA Task Load Index (NASA-TLX) scores. To evaluate the effectiveness of repeated practice, scores from these trainees on a separate delayed retention test were compared against historical controls who did not have scheduled repetitions. Twenty-one trainees completed the randomized study. Mean change in performance scores was significantly greater for those receiving PF (difference = 23.1 of 150 [95% confidence interval (CI): 0, 46.2], P = .05). Perceived workload was also significantly reduced (difference = -3.0 of 20 [95% CI: -5.8, -0.3], P = .04). Compared with historical controls (N = 93), the 21 with scheduled repeated practice had higher scores on the laparoscopic knot-tying assessment two weeks after the final repetition (difference = 1.5 of 10 [95% CI: 0.2, 2.8], P = .02). Personalized video feedback improves trainees' procedural performance and perceived workload compared with a task demonstration video. Brief monthly practice sessions support skill acquisition and retention.

  11. Total integrated energy system (TIES) feasibility analysis for the downtown redevelopment project, Pasadena, California

    Energy Technology Data Exchange (ETDEWEB)

    None

    1977-04-01

    The purpose of this study is to determine the most desirable method of serving the energy needs of a commercial development to be constructed in Pasadena, California. The factors that determine maximum desirability consist of the following: (1) maximum economic benefit to the energy user and to the surrounding community; (2) minimum usage of energy by both the energy user and the surrounding community; and (3) minimum introduction of pollutants into the community. The methods studied were the Total Integrated Energy System (TIES) concept in several configurations. The TIES concept differs from the ''total energy concept'' in the respect that the electric power output of the local power generation plant goes into the utility company distribution grid, rather than to the user. The user is served power from the grid, as with a conventional system, but also receives heating and cooling media produced from power generation by-product heat from the TIES plant. The effect of this concept is that a very large source-sink for electric energy is provided by the utility company grid. This, in turn, permits the plant to operate in response to instantaneous thermal demand, rather than instantaneous power demand. No auxiliary firing is ever required. No waste of unneeded by-product energy to atmosphere ever occurs. Balance is achieved by either delivering excess power into the grid or by withdrawing power production deficiency from the grid. Near-optimum efficiency is achieved during all operating conditions. There is no need whatsoever for the power-generating plant to be sized to meet the power demand, since it seldom, if ever, tracks the power demand. Sizing of the electric generation is solely a function of economics and the demand for waste heat.

  12. How Social Ties Influence Consumer: Evidence from Event-Related Potentials.

    Science.gov (United States)

    Luan, Jing; Yao, Zhong; Bai, Yan

    2017-01-01

    A considerable amount of marketing research has reported that consumers are more saliently influenced by friends (strong social ties) than by acquaintances and strangers (weak social ties). To shed light on the neural and psychological processes underlying such phenomenon, in this study we designed an amended S1-S2 paradigm (product-[reviewer-review]) that is based on realistic consumer purchase experiences. After incoming all given information (product, reviewer, review), participants were required to state their purchase intentions. The neurocognitive and emotional processes related to friend and stranger stimuli were delineated to suggest how social ties influence consumers during their shopping processes. Larger P2 (fronto-central scalp areas) and P3 (central and posterior-parietal scalp areas) components under stranger condition were elicited successfully. These findings demonstrate that the cognitive and emotional processing of friend and stranger stimuli occurs at stages of neural activity, and can be indicated by the P2 and P3 components. Electrophysiological data also support the hypothesis that different neural and emotional processing magnitude and strength underlie friend and stranger effect in the context of consumer purchase. During this process, the perception of stimuli evoked P2, subsequently emotional processing and attention modulation were activated and indicated by P2 and P3. The friend dominated phenomenon can be interpreted as the result of distinctive neurocognitive and emotional processing magnitude, which suggests that psychological and emotional factors can guide consumer decision making. This study consolidates that event related potential (ERP) methodology is likely to be a more sensitive method for investigating consumer behaviors. From the perspectives of management and marketing, our findings show that the P2 and P3 components can be employed as an indicator to probe the influential factors of consumer purchase intentions.

  13. Tension in the tie-down chains of a shipping container for hazardous material

    International Nuclear Information System (INIS)

    Lo, T.Y.

    1995-01-01

    Chains are frequently used to tie the shipping containers of hazardous material to a truck bed. The tie-down system is nonlinear when the container is subjected to a triaxial force during transit. It is nonlinear because chains cannot carry compressive force, and the base of the container may partially lift off from the truck bed. A method was developed to calculate the amount of tension in the chains. This methodology includes three assumptions: (1) No friction exists between the container and the truck bed; (2) The container and the truck bed are rigid; and (3) All chains are properly tightened (i.e., no slacks) during preparation for shipment. The methodology employs an iterative process of a linear tie-down system. This linear system is derived from the nonlinear system with two additional assumptions: (a) All chains can carry compression as well as tension; and (b) There is a point contact between the container and the truck bed. This linear system has a closed-form solution. After the first solution of the linear system is obtained, the unreasonable, or physically impossible, rotational degree of freedom of the container and the chains with compressive force are eliminated in the follow-up iterative calculations using the same linear system. Unreasonable rotation is detected when the results indicate a rotation of the container into the truck bed. Zero rotational value is assigned to this degree of freedom in the follow-up iterations. For chains under compression, the chain length is replaced with a fictitiously large value because a long chain carries essentially no load. This process usually needs only two or three iterations and can easily be carried out in a spread sheet using such programs as Microsoft Excel or LOTUS 123

  14. Airborne Microorganisms in Tie-stall Dairy Barns from Brasov County

    Directory of Open Access Journals (Sweden)

    Silvana Popescu

    2011-05-01

    Full Text Available The aim of this study was the assessment of the airborne microorganisms in tie-stall dairy cattle barns, through determination of the total number of bacteria (mesophilic bacteria, staphylococci, streptococci and gram-negative bacteria and fungi. We investigated 8 dairy cattle barns with tie-stalls in Brasov County during the winter of 2009. The mean numbers of bacteria and fungi in the morning and in the evening were: 1.02 °— 105 - 1.26 °— 105 CFU/m3 for mesophilic bacteria, 5.34 °— 104 - 5.91 °— 104 CFU/m3 for staphylococci, 2.93 °— 104 - 3.60 °— 104 CFU/m3 for streptococci, 2.17 °— 103 - 3.48 °— 103 CFU/m3 for gram-negative bacteria and 1.54 °— 104 - 2.75 °— 104 CFU/m3 for fungi. In the investigated cattle houses staphylococci represented 52.35 – 46.90%, streptococci were 28.73 – 28.57%, and the gram-negative bacteria were 2.13 – 2.76% within the overall number of mesophilic bacteria. The numbers of bacteria and fungi were slightly elevated in the evening comparative to the morning, but the differences were statistically insignificant (p>0.05. The great numbers of bacteria and fungi in the air of dairy cattle tie-stall barns indicate an elevated risk of disease for animals and human workers.

  15. Analysis of the tractive force pattern on a knot by force measurement during laparoscopic knot tying.

    Science.gov (United States)

    Takayasu, Kenta; Yoshida, Kenji; Kinoshita, Hidefumi; Yoshimoto, Syunsuke; Oshiro, Osamu; Matsuda, Tadashi

    2017-07-19

    Quantifying surgical skills assists novice surgeons when learning operative techniques. We measured the interaction force at a ligation point and clarified the features of the force pattern among surgeons with different skill levels during laparoscopic knot tying. Forty-four surgeons were divided into three groups based on experience: 13 novice (0-5 years), 16 intermediate (6-15 years), and 15 expert (16-30 years). To assess the tractive force direction and volume during knot tying, we used a sensor that measures six force-torque values (x-axis: Fx, y-axis: Fy, z-axis: Fz, and xy-axis: Fxy) attached to a slit Penrose drain. All participants completed one double knot and five single knot sequences. We recorded completion time, force volume (FV), maximum force (MF), time over 1.5 N, duration of non-zero force, and percentage time when vertical force exceeded horizontal force (PTz). There was a significant difference between groups for completion time (p = 0.007); FV (total: p = 0.002; Fx: p = 0.004, Fy: p = 0.007, Fxy: p = 0.004, Fz: p force (p = 0.029); and PTz (p force pattern at the ligation point during suturing by surgeons with three levels of experience using a force measurement system. We revealed that both force volume and force direction differed depending on surgeons' skill level during knot tying. Copyright © 2017. Published by Elsevier Inc.

  16. Angiopoietin-2 regulates gene expression in TIE2-expressing monocytes and augments their inherent proangiogenic functions.

    Science.gov (United States)

    Coffelt, Seth B; Tal, Andrea O; Scholz, Alexander; De Palma, Michele; Patel, Sunil; Urbich, Carmen; Biswas, Subhra K; Murdoch, Craig; Plate, Karl H; Reiss, Yvonne; Lewis, Claire E

    2010-07-01

    TIE2-expressing monocytes/macrophages (TEM) are a highly proangiogenic subset of myeloid cells in tumors. Here, we show that circulating human TEMs are already preprogrammed in the circulation to be more angiogenic and express higher levels of such proangiogenic genes as matrix metalloproteinase-9 (MMP-9), VEGFA, COX-2, and WNT5A than TIE2(-) monocytes. Additionally, angiopoietin-2 (ANG-2) markedly enhanced the proangiogenic activity of TEMs and increased their expression of two proangiogenic enzymes: thymidine phosphorylase (TP) and cathepsin B (CTSB). Three "alternatively activated" (or M2-like) macrophage markers were also upregulated by ANG-2 in TEMs: interleukin-10, mannose receptor (MRC1), and CCL17. To investigate the effects of ANG-2 on the phenotype and function of TEMs in tumors, we used a double-transgenic (DT) mouse model in which ANG-2 was specifically overexpressed by endothelial cells. Syngeneic tumors grown in these ANG-2 DT mice were more vascularized and contained greater numbers of TEMs than those in wild-type (WT) mice. In both tumor types, expression of MMP-9 and MRC1 was mainly restricted to tumor TEMs rather than TIE2(-) macrophages. Furthermore, tumor TEMs expressed higher levels of MRC1, TP, and CTSB in ANG-2 DT tumors than WT tumors. Taken together, our data show that although circulating TEMs are innately proangiogenic, exposure to tumor-derived ANG-2 stimulates these cells to exhibit a broader, tumor-promoting phenotype. As such, the ANG-2-TEM axis may represent a new target for antiangiogenic cancer therapies. Copyright 2010 AACR.

  17. TIE2-expressing monocytes as a diagnostic marker for hepatocellular carcinoma correlates with angiogenesis.

    Science.gov (United States)

    Matsubara, Tokuhiro; Kanto, Tatsuya; Kuroda, Shoko; Yoshio, Sachiyo; Higashitani, Koyo; Kakita, Naruyasu; Miyazaki, Masanori; Sakakibara, Mitsuru; Hiramatsu, Naoki; Kasahara, Akinori; Tomimaru, Yoshito; Tomokuni, Akira; Nagano, Hiroaki; Hayashi, Norio; Takehara, Tetsuo

    2013-04-01

    Angiogenesis is a critical step in the development and progression of hepatocellular carcinoma (HCC). Myeloid lineage cells, such as macrophages and monocytes, have been reported to regulate angiogenesis in mouse tumor models. TIE2, a receptor of angiopoietins, conveys pro-angiogenic signals and identifies a monocyte/macrophage subset with pro-angiogenic activity. Here, we analyzed the occurrence and kinetics of TIE2-expressing monocytes/macrophages (TEMs) in HCC patients. This study enrolled 168 HCV-infected patients including 89 with HCC. We examined the frequency of TEMs, as defined as CD14+CD16+TIE2+ cells, in the peripheral blood and liver. The localization of TEMs in the liver was determined by immunofluorescence staining. Micro-vessel density in the liver was measured by counting CD34+ vascular structures. We found that the frequency of circulating TEMs was significantly higher in HCC than non-HCC patients, while being higher in the liver than in the blood. In patients who underwent local radio-ablation or resection of HCC, the frequency of TEMs dynamically changed in the blood in parallel with HCC recurrence. Most TEMs were identified in the perivascular areas of tumor tissue. A significant positive correlation was observed between micro-vessel density in HCC and frequency of TEMs in the blood or tumors, suggesting that TEMs are involved in HCC angiogenesis. Receiver operating characteristic analyses revealed the superiority of TEM frequency to AFP, PIVKA-II and ANG-2 serum levels as diagnostic marker for HCC. TEMs increase in patients with HCC and their frequency changes with the therapeutic response or recurrence. We thus suggest that TEM frequency can be used as a diagnostic marker for HCC, potentially reflecting angiogenesis in the liver. Copyright © 2012 American Association for the Study of Liver Diseases.

  18. Time-resolved magnetization dynamics of cross-tie domain walls in permalloy microstructures

    International Nuclear Information System (INIS)

    Miguel, J; Kurde, J; Piantek, M; Kuch, W; Sanchez-Barriga, J; Heitkamp, B; Kronast, F; Duerr, H A; Bayer, D; Aeschlimann, M

    2009-01-01

    We report on a picosecond time-resolved x-ray magnetic circular dichroic-photoelectron emission microscopy study of the evolution of the magnetization components of a microstructured permalloy platelet comprising three cross-tie domain walls. A laser-excited photoswitch has been used to apply a triangular 80 Oe, 160 ps magnetic pulse. Micromagnetic calculations agree well with the experimental results, both in time and frequency, illustrating the large angle precession in the magnetic domains with magnetization perpendicular to the applied pulse, and showing how the magnetic vortices revert their core magnetization while the antivortices remain unaffected.

  19. A Systematic Method to Synthesize New Transformerless Full-bridge Grid-tied Inverters

    DEFF Research Database (Denmark)

    Wang, Hongliang; Burton, Sarah; Liu, Yan-Fei

    2014-01-01

    Many inverter topologies have been proposed to eliminate the leakage current of transformerless Full Bridge Grid-Tied photovoltaic (PV) inverters. These include implementations such as the H5, H6, and HERIC topologies, among others. In this paper, a new full bridge topology synthesis method, called...... the MN synthesis method, is proposed. The MN method introduces two criteria that can be used to synthesize all of the possible topologies, including the existing topologies as well as new simplified topologies. This method concludes that there are only 15 simplified topologies available. Most simplified...... topologies from MN method have been verified by existing papers and patents....

  20. A Simplified Control Method for Tie-Line Power of DC Micro-Grid

    OpenAIRE

    Yanbo Che; Jinhuan Zhou; Tingjun Lin; Wenxun Li; Jianmei Xu

    2018-01-01

    Compared with the AC micro-grid, the DC micro-grid has low energy loss and no issues of frequency stability, which makes it more accessible for distributed energy. Thus, the DC micro-grid has good potential for development. A variety of renewable energy is included in the DC micro-grid, which is easily affected by the environment, causing fluctuation of the DC voltage. For grid-connected DC micro-grid with droop control strategy, the tie-line power is affected by fluctuations in the DC voltag...

  1. LDA measurement of droplet behavior across tie plate during dispersed flow portion of loca reflood

    International Nuclear Information System (INIS)

    Lee, S.L.; Srinivasan, J.; Cho, S.K.

    1980-01-01

    The flow of an air-water droplet dispersion in a simulated 3-D test section in the reflood portion of LOCA was studied. For this purpose, a new scheme of Laser-Doppler Anemometry for the simultaneous measurement of size and velocity of large-size [0.5 mm-6 mm] droplets was developed and utilized. It was observed that the size distribution of the reentrained droplets depends mainly on the flow regimes and is essentially independent of that of the incoming dispersion below the tie plate. 8 refs

  2. China-USA economic relations: bilateral ties and multilateral economic projects

    Directory of Open Access Journals (Sweden)

    S. M. Troush

    2017-01-01

    Full Text Available The article is devoted to the study of problematic issues of the change of US-China trade is going up notwithstanding the slowdown of Chinese economy. Those US fi rms who placed production in China became more involved into Chinese internal market. Chinese investments into US prevail over the US investments in China. The decisions of the Chinese leadership to set up the new market priorities in the economic development are implemented with obvious diffi culties, but being implemented, could stimulate US-China ties.

  3. Time-resolved magnetization dynamics of cross-tie domain walls in permalloy microstructures

    Energy Technology Data Exchange (ETDEWEB)

    Miguel, J; Kurde, J; Piantek, M; Kuch, W [Institut fuer Experimentalphysik, Freie Universitaet Berlin, Arnimallee 14, D-14195 Berlin (Germany); Sanchez-Barriga, J; Heitkamp, B; Kronast, F; Duerr, H A [Helmholtz-Zentrum Berlin fuer Materialien und Energie, Elektronenspeicherring BESSY II, Albert-Einstein-Strasse 15, D-12489 Berlin (Germany); Bayer, D; Aeschlimann, M, E-mail: jorge.miguel@fu-berlin.d [Fachbereich Physik, Universitaet Kaiserslautern, Erwin-Schroedinger Strasse 46, D-67663 Kaiserslautern (Germany)

    2009-12-02

    We report on a picosecond time-resolved x-ray magnetic circular dichroic-photoelectron emission microscopy study of the evolution of the magnetization components of a microstructured permalloy platelet comprising three cross-tie domain walls. A laser-excited photoswitch has been used to apply a triangular 80 Oe, 160 ps magnetic pulse. Micromagnetic calculations agree well with the experimental results, both in time and frequency, illustrating the large angle precession in the magnetic domains with magnetization perpendicular to the applied pulse, and showing how the magnetic vortices revert their core magnetization while the antivortices remain unaffected.

  4. Knowledge-based network ties in early rapidly internationalising small firms

    DEFF Research Database (Denmark)

    Masango, Shingairai Grace; Marinova, Svetla Trifonova

    2014-01-01

    strong knowledge-based contacts. The ERISF acts as the source that provides the technical information and knowledge, which is then adopted by their network partners. This means that the ERISF’s product and technological capabilities drive the international knowledge creation process. The findings provide...... a holistic characterisation of the concept of knowledge in ERISF internationalisation. Within their interorganisational relationships, ERISFs are involved in knowledge creation, knowledge transfer and knowledge adoption activities. Network ties developed in existing knowledge pools are extended to new...

  5. LLCL-Filter Based Single-Phase Grid-Tied Aalborg Inverter

    DEFF Research Database (Denmark)

    Wu, Weimin; Feng, Shuangshuang; Ji, Junhao

    2014-01-01

    The Aalborg Inverter is a new type of high efficient DC/AC grid-tied inverter, where the input DC voltage can vary in a wide range. Compared with the LCL-filter, the LLCL-filter can save the total inductance for the conventional voltage source inverter. In this paper, an LLCL-filter based Aalborg...... Inverter is proposed and its character is illustrated through the small signal analysis in both “Buck” and “Buck-Boost” mode. From the modeling, it can be seen that the resonant inductor in the capacitor loop has not brought extra control difficulties, whereas more inductance in the power loop can be saved...

  6. The modelling of two DOF joints controlled by elastic inner ties

    Directory of Open Access Journals (Sweden)

    Ożóg Dominik

    2017-01-01

    Full Text Available This paper considers the mathematical model of two types of joints that can be used to connect the arms of two robots. The first of them is a simple revolute joint with one degree of freedom and the second is a universal joint with two degrees of freedom. Each of them is controlled using elastic ties that run in the joints and are connected to the inside of the arm joints. This paper describes a study of kinematics, dynamics properties and Extended Denavit-Hartenberg Notation parameters mentioned joints.

  7. Beam-Steerable Microstrip-Fed Bow-Tie Antenna Array for Fifth Generation Cellular Communications

    DEFF Research Database (Denmark)

    Ojaroudiparchin, Naser; Shen, Ming; Pedersen, Gert Frølund

    2016-01-01

    The design and performance of mm-wave phased array antenna for 5G mobile broadband communication systems has been provided in this manuscript. The antenna is designed on a N9000 PTFE substrate with 0.787 mm thickness and 2.2 dielectric constant and 65×130 mm2 overall dimension. Eight elements...... of bow-tie antennas have been used at the top-edge region of mobile phone PCB. The antenna elements fed by microstrip lines are designed to operate at 17 GHz. The simulated results give good performances in terms of different antenna parameters. In addition, an investigation on the distance between...

  8. Liquid Crystal Bow-Tie Microstrip antenna for Wireless Communication Applications

    Directory of Open Access Journals (Sweden)

    B.T.P.Madhav

    2014-06-01

    Full Text Available In this paper we presented the design and analysis of Bow-Tie antenna on liquid crystal substrate, which is suitable for the Bluetooth/WLAN-2.4/WiBree/ZigBee applications. The Omni-directional radiation patterns along with moderate gain make the proposed antenna suitable for above mentioned applications. Details of the antenna design and simulated results Return loss, Input impedance, Radiation Patterns, E-Field, H-Field and Current Distributions, VSWR are presented and discussed. The proposed antenna is simulated at 2.4 GHz using Ansoft HFSS-11.

  9. Tie2-expressing monocytes (TEMs): novel targets and vehicles of anticancer therapy?

    Science.gov (United States)

    De Palma, Michele; Naldini, Luigi

    2009-08-01

    There is a growing interest in understanding the complex interactions between bone marrow-derived myeloid-lineage cells and angiogenesis in tumors. Such interest has been revived recently by the observation that tumor-infiltrating myeloid cells convey proangiogenic programs that can counteract the activity of antiangiogenic drugs in mouse tumor models. Among myeloid cells, Tie2-expressing monocytes (TEMs) appear to have nonredundant function in promoting tumor angiogenesis and growth in mouse models. The identification and functional characterization of TEMs in mice and humans may provide novel molecular targets for anticancer therapy. Moreover, TEMs may be exploited to deliver antitumor drugs specifically to the tumor microenvironment.

  10. Flat tie-line power scheduling control of grid-connected hybrid microgrids

    DEFF Research Database (Denmark)

    Xiao, Zhao xia; Guerrero, Josep M.; Shuang, Jia

    2018-01-01

    In future active distribution networks (ADNs), microgrids (MGs) may have the possibility to control the power dispatched to the ADN by coordinating the output power of their multiple renewable generation units and energy storage units (ESUs). In this way, each MG may support the active distribution....... Also, a method to calculate the tie-line power flow to be exchanged between the MG and the ADN is explored, and a power ramp rate is given between different dispatch intervals. Finally, a simulation model of the hybrid MG is built and tested. Simulation results show that the proposed hierarchical...

  11. Laboratory Modeling of Self-Formed Leveed Channels From Sediment-Laden Flows Entering Still Water

    Science.gov (United States)

    Rowland, J. C.; Dietrich, W. E.

    2004-12-01

    Self-formed leveed channels constructed by deposition of suspended sediment from sediment-laden flows entering still water are common features in nature. Such channels drive delta progradation, develop at tidal inlets and occur where mainstem river flows empty into oxbows and blocked valley lakes. Presently there is no theory for the formation of such channels. This lack of theory is partly due to a lack of field or laboratory studies that provide insight about the mechanism controlling these self-formed, propagating channels. The creation of such features in the laboratory, have proved illusive to date. Our ongoing experiments aimed at modeling the formation of floodplain tie channels provide insight into the necessary conditions for levee formation and channel growth. Under conditions of steady water discharge, constant sediment feed rate, unimodal sediment distribution and invariant basin stage we are able to create subaqueous lateral bars (submerged levees) along the margins of a sediment laden jet. Our results highlight the sensitivity of channel formation to issues of scaling and experimental design. In the laboratory, levee formation has only been possible with the use of plastic particles (specific gravity ~1.5); complete bed alluviation and dune formation results from the use of particles with specific gravities of ~ 2.65 across a range grain diameters and shapes. We hypothesize this effect is related to high entrainment thresholds relative to suspension thresholds of small (< 100 mm) natural particles under conditions of reduced turbulence in laboratory scaled flows. Additionally, both the width to depth ratio and the form of the outlet channel introducing the sediment laden flow into the experimental basin exert a strong control on sedimentation pattern and levee growth. Continuing experiments are focused on generating emergent channel levees and a basin ward propagation of the channel by adjusting the form of the feed channel, varying basin stage, and

  12. Fuel channel refilling

    International Nuclear Information System (INIS)

    Shoukri, M.; Abdul-Razzak, A.

    1992-11-01

    This report extends the work reported in document INFO-0370 on fuel channel refilling by providing analysis of the refilling tests conducted using the RD-14 and RD-14M test facilities. The analysis focuses on the general thermal-hydraulic characteristics of the facilities following various small and large inlet and outlet header breaks with emergency coolant injection. The two-fluid model thermal-hydraulic computer code CATHENA was tested against results obtained from selected experiments carried out in the two facilities. Conclusions related to the effect of break size, mode of emergency core injection, primary pump operation and parallel channels are presented. (Author) (116 figs., 17 tabs., 53 refs.)

  13. Ion channels in glioblastoma.

    Science.gov (United States)

    Molenaar, Remco J

    2011-01-01

    Glioblastoma is the most common primary brain tumor with the most dismal prognosis. It is characterized by extensive invasion, migration, and angiogenesis. Median survival is only 15 months due to this behavior, rendering focal surgical resection ineffective and adequate radiotherapy impossible. At this moment, several ion channels have been implicated in glioblastoma proliferation, migration, and invasion. This paper summarizes studies on potassium, sodium, chloride, and calcium channels of glioblastoma. It provides an up-to-date overview of the literature that could ultimately lead to new therapeutic targets.

  14. Fuel channel refilling

    International Nuclear Information System (INIS)

    Shoukri, M.; Abdul-Razzak, A.

    1990-04-01

    Analysis of existing data on fuel channel refilling is presented. The analysis focuses on the data obtained using the Stern Laboratories Cold Water Injection Test (CWIT) Facility. The two-fluid model thermal-hydraulics computer code CATHENA is also used to simulate experimental results on fuel channel refilling from both the CWIT and RD-14 facilities. Conclusions related to single and double break tests, including the effect of non-condensible gases, are presented. A set of recommendations is given for further analysis and separate effect experiments. (67 figs., 5 tabs., 24 refs.)

  15. Potassium channels in brain mitochondria.

    Science.gov (United States)

    Bednarczyk, Piotr

    2009-01-01

    Potassium channels are the most widely distributed class of ion channels. These channels are transmembrane proteins known to play important roles in both normal and pathophysiological functions in all cell types. Various potassium channels are recognised as potential therapeutic targets in the treatment of Parkinson's disease, Alzheimer's disease, brain/spinal cord ischaemia and sepsis. In addition to their importance as therapeutic targets, certain potassium channels are known for their beneficial roles in anaesthesia, cardioprotection and neuroprotection. Some types of potassium channels present in the plasma membrane of various cells have been found in the inner mitochondrial membrane as well. Potassium channels have been proposed to regulate mitochondrial membrane potential, respiration, matrix volume and Ca(+) ion homeostasis. It has been proposed that mitochondrial potassium channels mediate ischaemic preconditioning in various tissues. However, the specificity of a pharmacological agents and the mechanisms underlying their effects on ischaemic preconditioning remain controversial. The following potassium channels from various tissues have been identified in the inner mitochondrial membrane: ATP-regulated (mitoK(ATP)) channel, large conductance Ca(2+)-regulated (mitoBK(Ca)) channel, intermediate conductance Ca(2+)-regulated (mitoIK(Ca)) channel, voltage-gated (mitoKv1.3 type) channel, and twin-pore domain (mitoTASK-3) channel. It has been shown that increased potassium flux into brain mitochondria induced by either the mitoK(ATP) channel or mitoBK(Ca) channel affects the beneficial effects on neuronal cell survival under pathological conditions. Recently, differential distribution of mitoBK(Ca) channels has been observed in neuronal mitochondria. These findings may suggest a neuroprotective role for the mitoBK(Ca) channel in specific brain structures. This minireview summarises current data on brain mitochondrial potassium channels and the efforts to identify

  16. MITOCHONDRIAL BKCa CHANNEL

    Directory of Open Access Journals (Sweden)

    Enrique eBalderas

    2015-03-01

    Full Text Available Since its discovery in a glioma cell line 15 years ago, mitochondrial BKCa channel (mitoBKCa has been studied in brain cells and cardiomyocytes sharing general biophysical properties such as high K+ conductance (~300 pS, voltage-dependency and Ca2+-sensitivity. Main advances in deciphering the molecular composition of mitoBKCa have included establishing that it is encoded by the Kcnma1 gene, that a C-terminal splice insert confers mitoBKCa ability to be targeted to cardiac mitochondria, and evidence for its potential coassembly with β subunits. Notoriously, β1 subunit directly interacts with cytochrome c oxidase and mitoBKCa can be modulated by substrates of the respiratory chain. mitoBKCa channel has a central role in protecting the heart from ischemia, where pharmacological activation of the channel impacts the generation of reactive oxygen species and mitochondrial Ca2+ preventing cell death likely by impeding uncontrolled opening of the mitochondrial transition pore. Supporting this view, inhibition of mitoBKCa with Iberiotoxin, enhances cytochrome c release from glioma mitochondria. Many tantalizing questions remain. Some of them are: how is mitoBKCa coupled to the respiratory chain? Does mitoBKCa play non-conduction roles in mitochondria physiology? Which are the functional partners of mitoBKCa? What are the roles of mitoBKCa in other cell types? Answers to these questions are essential to define the impact of mitoBKCa channel in mitochondria biology and disease.

  17. Chemistry in Microfluidic Channels

    Science.gov (United States)

    Chia, Matthew C.; Sweeney, Christina M.; Odom, Teri W.

    2011-01-01

    General chemistry introduces principles such as acid-base chemistry, mixing, and precipitation that are usually demonstrated in bulk solutions. In this laboratory experiment, we describe how chemical reactions can be performed in a microfluidic channel to show advanced concepts such as laminar fluid flow and controlled precipitation. Three sets of…

  18. Workshop on Gas Channels

    Science.gov (United States)

    2013-02-07

    Effect of pressure on gas permeability. In Fish … Different channels or splice variants at different depth.  HRE (hypoxia-response elements): which...proteins unexpectedly have HREs . HIF-1.  Shear stress:  expression of NOS  Are different splice variants used under different conditions?  Size

  19. Cross-border ties as a source of risk and resilience: Do cross-border ties moderate the relationship between migration-related stress and psychological distress among Latino migrants in the United States?

    Science.gov (United States)

    Torres, Jacqueline M.; Alcántara, Carmela; Rudolph, Kara E.; Viruell-Fuentes, Edna A.

    2017-01-01

    Few studies have examined the associations between health and the cross-border ties that migrants maintain with their family members in communities of origin. We draw on theory related to social ties, ethnic identity, and mental health to examine cross-border ties as potential moderators of the association between migration-related stress and psychological distress among Latino migrants. Using data from the National Latino and Asian American Survey, we find that remittance sending is associated with significantly lower levels of psychological distress for Cuban migrants, and difficulty visiting home is associated with significantly greater psychological distress for Puerto Rican migrants. There were significant associations between migration-related stressors and psychological distress, although these associations fell to non-significance after accounting for multiple testing. We found little evidence that cross-border ties either buffer or exacerbate the association between migration-related stressors and psychological distress. We consider the findings within the current political and historical context of cross-border ties and separation. PMID:27803264

  20. Cross-border Ties as Sources of Risk and Resilience: Do Cross-border Ties Moderate the Relationship between Migration-related Stress and Psychological Distress for Latino Migrants in the United States?

    Science.gov (United States)

    Torres, Jacqueline M; Alcántara, Carmela; Rudolph, Kara E; Viruell-Fuentes, Edna A

    2016-12-01

    Few studies have examined the associations between health and the cross-border ties that migrants maintain with their family members in communities of origin. We draw on theory related to social ties, ethnic identity, and mental health to examine cross-border ties as potential moderators of the association between migration-related stress and psychological distress among Latino migrants. Using data from the National Latino and Asian American Survey, we find that remittance sending is associated with significantly lower levels of psychological distress for Cuban migrants, and difficulty visiting home is associated with significantly greater psychological distress for Puerto Rican migrants. There were significant associations between migration-related stressors and psychological distress, although these associations fell to nonsignificance after accounting for multiple testing. We found little evidence that cross-border ties either buffer or exacerbate the association between migration-related stressors and psychological distress. We consider the findings within the current political and historical context of cross-border ties and separation. © American Sociological Association 2016.

  1. Market Assessment of Residential Grid-Tied PV Systems in Colorado

    Energy Technology Data Exchange (ETDEWEB)

    Farhar, B.; Coburn, T.

    2000-09-29

    This report presents research done in response to a decision by the Colorado Governor's Office of Energy Conservation and Management (OEC) and Colorado utility companies to consider making residential grid-tied photovoltaic (PV) systems available in Colorado. The idea was to locate homeowners willing to pay the costs of grid-tied PV (GPV) systems without batteries-$8,000 or $12,000 for a 2- or 3-kilowatt (kW) system, respectively, in 1996. These costs represented two-thirds of the actual installed cost of $6 per watt at that time and assumed the remainder would be subsidized. The National Renewable Energy Laboratory (NREL) and OEC partnered to conduct a market assessment for GPV technology in Colorado. The study encompassed both qualitative and quantitative phases. The market assessment concluded that a market for residential GPV systems exists in Colorado today. That market is substantial enough for companies to successfully market PV systems to Colorado homeowners. These homeo wners appear ready to learn more, inform themselves, and actively purchase GPV systems. The present situation is highly advantageous to Colorado's institutions-primarily its state government and its utility companies, and also its homebuilders-if they are ready to move forward on GPV technology.

  2. Constructing Current Singularity in a 3D Line-tied Plasma

    Science.gov (United States)

    Zhou, Yao; Huang, Yi-Min; Qin, Hong; Bhattacharjee, A.

    2018-01-01

    We revisit Parker’s conjecture of current singularity formation in 3D line-tied plasmas using a recently developed numerical method, variational integration for ideal magnetohydrodynamics in Lagrangian labeling. With the frozen-in equation built-in, the method is free of artificial reconnection, and hence it is arguably an optimal tool for studying current singularity formation. Using this method, the formation of current singularity has previously been confirmed in the Hahm–Kulsrud–Taylor problem in 2D. In this paper, we extend this problem to 3D line-tied geometry. The linear solution, which is singular in 2D, is found to be smooth for arbitrary system length. However, with finite amplitude, the linear solution can become pathological when the system is sufficiently long. The nonlinear solutions turn out to be smooth for short systems. Nonetheless, the scaling of peak current density versus system length suggests that the nonlinear solution may become singular at finite length. With the results in hand, we can neither confirm nor rule out this possibility conclusively, since we cannot obtain solutions with system length near the extrapolated critical value.

  3. Use of a Barbed Suture Tie-Over Technique for Skin Graft Dressings: A Case Series

    Directory of Open Access Journals (Sweden)

    Kenneth M Joyce

    2015-05-01

    Full Text Available BackgroundA tie-over dressing is the accepted method to secure skin grafts in order to prevent haematoma or seroma formation. We describe the novel application of a barbed suture tie-over for skin graft dressing. The barbs act as anchors in the skin so constant tensioning of the suture is not required.MethodsFrom January 2014 to August 2014 we used the technique in 30 patients with skin defects requiring split-thickness or full-thickness grafts. Patient demographics, clinicopathological details and graft outcome were collected prospectively.ResultsThe majority of cases were carried out for split-thickness skin grafts (n=19 used on the lower limb (n=20. The results of this novel technique were excellent with complete (100% graft take in all patients.ConclusionsOur results demonstrate the clinical application of a barbed device for securing skin grafts with excellent results. We find the technique quick to perform and the barbed device easy to handle, which can be applied without the need for an assistant.

  4. Strut and tie modeling for RC short beams with corroded stirrups

    Directory of Open Access Journals (Sweden)

    Ahmed K. El-Sayed

    Full Text Available Corrosion of steel reinforcement is one of the major problems that shorten the service life of reinforced concrete (RC structures. Steel stirrups, due to their location as an outer reinforcement, are more susceptible to corrosion problems and damage. However, there is limited research work in the literature on the effects of stirrup corrosion on the shear strength of RC beams. This paper attempts to evaluate analytically the residual shear strength of RC short beams with corrosion-damaged stirrups. The shear strength of short or deep beams are generally determined using the strut and tie model. The corrosion effects were implemented in the model to make it capable of predicting the residual shear capacity of RC beams with corroded stirrups. The effect of corrosion is implemented considering the reduction in geometry of the concrete cross section due to spalling and reduction in effective compressive strength of concrete due to corrosion cracks. The proposed strut and tie model which accounts for the corrosion effects was verified using the experimental data available in the literature, and good agreement was found.

  5. Changes of Personal Network Composition and Inter-Group Ties from 1987 to 2005 in Hungary

    Directory of Open Access Journals (Sweden)

    VARGA V., Attila

    2014-04-01

    Full Text Available The following paper presents the changes and stability of assortative mixing, and inter-group ties in Hungary from 1987 to 2005. The demographic categories under investigation are age, sex, and education. The analysis has a special focus on the rearrangement of the context of tie formation, and the inequality of receiving choices into personal networks along social categories. The most substantial change during the period, is the strong decrease in gender homophily, and some strengthening of intergenerationalties. Both of these findings are in line with the observation that personal networks are recruited more often among the members of the nuclear-family. This latter phenomenon is probably due to the shrinking network size. However, this set of finding is prone to the methodological criticism formulated in the US context, that these observations are in fact the result of the interviewer effect. Finally, the study found stable patterns of educational network prestige, and describes the changes of social capital attached to categories of gender and age.

  6. A composite passive damping method of the LLCL-filter based grid-tied inverter

    DEFF Research Database (Denmark)

    Wu, Weimin; Huang, Min; Sun, Yunjie

    2012-01-01

    This paper investigates the maximum and the minimum gain of the proportional resonant based grid current controller for a grid-tied inverter with a passive damped high-order power filter. It is found that the choice of the controller gain is limited to the local maximum amplitude determined by Q......-factor around the characteristic frequency of the filter and grid impedance. To obtain the Q-factor of a high-order system, an equivalent circuit analysis method is proposed and illustrated through several classical passive damped LCL- and LLCL-filters. It is shown that both the RC parallel damper...... that is in parallel with the capacitor of the LCL-filter or with the Lf-Cf resonant circuit of the LLCL-filter, and the RL series damper in series with the grid-side inductor have their own application limits. Thus, a composite passive damped LLCL-filter for the grid-tied inverter is proposed, which can effectively...

  7. Prospective, randomized, controlled trial of polymer cable ties versus standard wire closure of midline sternotomy.

    Science.gov (United States)

    Marasco, Silvana F; Fuller, Louise; Zimmet, Adam; McGiffin, David; Seitz, Michael; Ch'ng, Stephanie; Gangahanumaiah, Shivanand; Bailey, Michael

    2018-04-16

    Midline sternotomy remains the most common access incision for cardiac operations. Traditionally, the sternum is closed with stainless steel wires. Wires are well known to stretch and break, however, leading to pain, nonunion, and potential deep sternal wound infection. We hypothesized that biocompatible plastic cable ties would achieve a more rigid sternal fixation, reducing postoperative pain and analgesia requirements. A prospective, randomized study compared the ZIPFIX (De Puy Synthes, West Chester, Pa) sternal closure system (n = 58) with standard stainless steel wires (n = 60). Primary outcomes were pain and analgesia requirements in the early postoperative period. Secondary outcome was sternal movement, as assessed by ultrasound at the postoperative follow-up visit. Groups were well matched in demographic and operative variables. There were no significant differences between groups in postoperative pain, analgesia, or early ventilatory requirements. Patients in the ZIPFIX group had significantly more movement in the sternum and manubrium on ultrasound at 4 weeks. ZIPFIX sternal cable ties provide reliable closure but no demonstrable benefit in this study in pain or analgesic requirements relative to standard wire closure after median sternotomy. Crown Copyright © 2018. Published by Elsevier Inc. All rights reserved.

  8. Social organization and social ties: their effects on sexual harassment victimization in the workplace.

    Science.gov (United States)

    Snyder, Jamie A; Scherer, Heidi L; Fisher, Bonnie S

    2012-01-01

    Despite work organizations' attempts to reduce sexual harassment, it continues to be a salient issue for employers across all occupations. Extending social disorganization theory to the work environment, this study examines the relationship between workplace organization, social ties, and sexual harassment victimization. Survey responses to the 2002 and 2006 Quality of Working Life module from the General Social Survey by a sample of 3,530 adult men and women employees in the United States were used. Logistic regression models were estimated for men and women separately to estimate the effect of workplace characteristics on the risk of sexual harassment victimization. Employees who reported poor workplace relations between management and employees and lower coworker social ties were more likely to experience sexual harassment in their work environments. Specific workplace characteristics such as low productivity, poor time management, and inadequate administrative support were significantly related to increased sexual harassment risk. No significant gender differences were found across models suggesting that the predictors of sexual harassment are similar for men and women. This study demonstrates that workplace characteristics are related to sexual harassment risk in the workplace. Suggestions for sexual harassment prevention, including management and organizational strategies, are discussed.

  9. Child first language and adult second language are both tied to general-purpose learning systems.

    Science.gov (United States)

    Hamrick, Phillip; Lum, Jarrad A G; Ullman, Michael T

    2018-02-13

    Do the mechanisms underlying language in fact serve general-purpose functions that preexist this uniquely human capacity? To address this contentious and empirically challenging issue, we systematically tested the predictions of a well-studied neurocognitive theory of language motivated by evolutionary principles. Multiple metaanalyses were performed to examine predicted links between language and two general-purpose learning systems, declarative and procedural memory. The results tied lexical abilities to learning only in declarative memory, while grammar was linked to learning in both systems in both child first language and adult second language, in specific ways. In second language learners, grammar was associated with only declarative memory at lower language experience, but with only procedural memory at higher experience. The findings yielded large effect sizes and held consistently across languages, language families, linguistic structures, and tasks, underscoring their reliability and validity. The results, which met the predicted pattern, provide comprehensive evidence that language is tied to general-purpose systems both in children acquiring their native language and adults learning an additional language. Crucially, if language learning relies on these systems, then our extensive knowledge of the systems from animal and human studies may also apply to this domain, leading to predictions that might be unwarranted in the more circumscribed study of language. Thus, by demonstrating a role for these systems in language, the findings simultaneously lay a foundation for potentially important advances in the study of this critical domain.

  10. Dynamic Equivalent Modeling of a Grid-Tied Microgrid Based on Characteristic Model and Measurement Data

    Directory of Open Access Journals (Sweden)

    Changchun Cai

    2017-11-01

    Full Text Available Microgrids can significantly improve the utilization of distributed generation (DG and the reliability of the power supply. However, in the grid-tied operational mode, the interaction between the microgrid and the distribution network cannot be ignored. The paper proposes an equivalent modeling method for the microgrid under grid-tied mode based on a characteristic model. It can simplify the microgrid model in the numerical simulation of the distribution network. The proposed equivalent model can present the dynamic response of a microgrid but not miss any of its primary characteristics. The characteristic model is represented by a low-order time-varying differential equation with the same characteristics of the original microgrid system. During the modeling process, the voltage and the power exchanged between the microgrid and distribution network are collected as the training data for the identification of model parameters. A recursive damped least squares algorithm (RDLS is used for the parameter identification. A microgrid system containing different DGs is built to test the proposed modeling method in DIgSILENT, and the results show that the proposed dynamic equivalent modeling method is effective and the characteristic model can present the dynamic behaviors of the detailed model of a microgrid.

  11. A Market Assessment of Residential Grid-Tied PV Systems in Colorado: Executive Summary

    Energy Technology Data Exchange (ETDEWEB)

    Farhar, B.; Coburn, T.

    2000-09-13

    This is the Executive Summary of a report that presents research done in response to a decision by the Colorado Governor's Office of Energy Conservation and Management (OEC) and Colorado utility companies to consider making residential grid-tied photovoltaic (PV) systems available in Colorado. The idea was to locate homeowners willing to pay the costs of grid-tied PV (GPV) systems without batteries--$8,000 or $12,000 for a 2- or 3-kilowatt (kW) system, respectively, in 1996. These costs represented two-thirds of the actual installed cost of $6 per watt at that time and assumed the remainder would be subsidized. The National Renewable Energy Laboratory (NREL) and OEC partnered to conduct a market assessment for GPV technology in Colorado. The study encompassed both qualitative and quantitative phases. The market assessment concluded that a market for residential GPV systems exists in Colorado today. That market is substantial enough for companies to successfully market PV systems to Colorado homeowners. These homeowners appear ready to learn more, inform themselves, and actively purchase GPV systems. The present situation is highly advantageous to Colorado's institutions--primarily its state government and its utility companies, and also its homebuilders--if they are ready to move forward on GPV technology.

  12. Approaches to Addressing Service Selection Ties in Ad Hoc Mobile Cloud Computing

    Directory of Open Access Journals (Sweden)

    Ayotuyi Tosin Akinola

    2018-01-01

    Full Text Available The ad hoc mobile cloud (AMC allows mobile devices to connect together through a wireless connection or any other means and send a request for web services from one to another within the mobile cloud. However, one of the major challenges in the AMC is the occurrence of dissatisfaction experienced by the users. This is because there are many services with similar functionalities but varying nonfunctional properties. Moreover, another resultant cause of user dissatisfaction being coupled with runtime redundancy is the attainment of similar quality computations during service selection, often referred to as “service selection ties.” In an attempt to address this challenge, service selection mechanisms for the AMC were developed in this work. This includes the use of selected quality of service properties coupled with user feedback data to determine the most suitable service. These mechanisms were evaluated using the experimental method. The evaluation of the mechanisms mainly focused on the metrics that evaluate the satisfaction of users' interest via the quantitative evaluation. The experiments affirmed that the use of the shortest distance can help to break selection ties between potential servicing nodes. Also, a continuous use of updated and unlimited range of users' assessments enhances an optimal service selection.

  13. Can TIE-2 expressing monocytes represent a novel marker for hepatocellular carcinoma?

    Science.gov (United States)

    Dapas, Barbara; Grassi, Mario; Grassi, Gabriele

    2014-08-01

    Hepatocellular carcinoma (HCC), the predominant form of primary liver cancer, is a global health problem representing the sixth most common cancer and the third cause of cancer related death worldwide. The number of deaths per year in HCC is comparable to the incidence number, underlying the aggressive behavior of HCC and the modest efficacy of available curative treatments. Effective HCC treatment is problematic also due to the lack of early and specific diagnostic markers. In this regard, particular interest has been put on the tyrosine kinase with Ig and endothelial growth factor (EGF) homology domains 2 (TIE2), a receptor of angiopoietins, predominantly present on endothelial cells but also observed on monocytes [TIE-2-expressing monocytes (TEMs)]. Recently, a work by Matsubara et al. showed that the amount of circulating TEMs is higher in hepatitis virus C (HCV)/HCC patients compared to HCV patients or healthy subjects. Additionally the authors showed that TEMs have a diagnostic potential for HCC. Whereas the molecular mechanisms responsible for this observation remain elusive and further studies are necessary to confirm this finding, the work of Matsubara et al. may contribute to the identification of a novel HCC prognostic and diagnostic marker.

  14. Angiopoietin-2 and soluble Tie-2 receptor plasma levels in children with obstructive sleep apnea and obesity.

    Science.gov (United States)

    Gozal, David; Khalyfa, Abdelnaby; Qiao, Zhuanghong; Smith, Dale L; Philby, Mona F; Koren, Dorit; Kheirandish-Gozal, Leila

    2017-06-01

    Obstructive sleep apnea (OSA) is a prevalent condition, especially in children with obesity, and is associated with increased risk for metabolic syndrome (MetS). Angiopoietins have been identified as potential biomarkers of endothelial dysfunction and MetS. In adults, angiopoietin-2 (Ang-2) and its soluble receptor (sTie-2) are associated with diabetes, hypertension, and obesity and could be increased in children with OSA and obesity, particularly those with evidence of cardiometabolic alterations. One hundred twenty-six children (7.4 ± 2.0 years) were consecutively recruited and underwent overnight polysomnography, as well as endothelial function and BMI z score assessments and a fasting blood draw the morning after the sleep study. In addition to lipid profile, glucose and insulin levels, and homeostatic model assessment of insulin resistance (HOMA-IR), Ang-2 and sTie-2 concentrations were determined. Children with obesity and OSA had significantly elevated plasma Ang-2 and sTie-2 levels compared to corresponding controls with and without obesity. Furthermore, endothelial function (Tmax) and HOMA-IR were linearly and independently associated with Ang-2 and sTie-2 levels. In a small subset of children (n = 14), treatment of OSA by adenotonsillectomy resulted in reductions of Ang-2 and sTie-2 (P obesity, particularly when endothelial dysfunction or insulin resistance is detectable, and appear to decrease upon OSA treatment. © 2017 The Obesity Society.

  15. A comparison of tape-tying versus a tube-holding device for securing endotracheal tubes in adults.

    Science.gov (United States)

    Murdoch, E; Holdgate, A

    2007-10-01

    During the transfer of intubated patients, endotracheal tube security is paramount. This study aims to compare two methods of securing an endotracheal tube in adults: tying with a cloth tape versus the Thomas Endotracheal Tube Holder (Laerdal). A manikin-based study was performed using paramedics and critical care doctors (consultants and senior trainees) as participants. Each participant was asked to secure an endotracheal tube that had been placed within the trachea of a manikin a total of six times, the first three times using tied cloth tape and the last three times using a Thomas Endotracheal Tube Holder. Following each 'fixation' and after the participant had left the room, the security of the tube was tested by applying a fixed force laterally and to the right by dropping a 1.25 kg weight a distance of 50 cm. The amount of movement of the tube with respect to the teeth was measured and recorded in millimetres. Two-hundred-and-seventy tube fixations (135 tied vs. 135 tube holder) were performed by 45 participants. The degree of tube movement was significantly higher when the tube was secured with a tie compared with when the tube holder was used (median movement 22 mm vs. 4 mm, P tube holder device minimised tube movement in a manikin model when compared with conventional tape tying. The use of this device when transporting intubated patients may reduce the risk of tube displacement though further clinical studies are warranted.

  16. Transosseous-equivalent rotator cuff repair: a systematic review on the biomechanical importance of tying the medial row.

    Science.gov (United States)

    Mall, Nathan A; Lee, Andrew S; Chahal, Jaskarndip; Van Thiel, Geoffrey S; Romeo, Anthony A; Verma, Nikhil N; Cole, Brian J

    2013-02-01

    Double-row and transosseous-equivalent repair techniques have shown greater strength and improved healing than single-row techniques. The purpose of this study was to determine whether tying of the medial-row sutures provides added stability during biomechanical testing of a transosseous-equivalent rotator cuff repair. We performed a systematic review of studies directly comparing biomechanical differences. Five studies met the inclusion and exclusion criteria. Of the 5 studies, 4 showed improved biomechanical properties with tying the medial-row anchors before bringing the sutures laterally to the lateral-row anchors, whereas the remaining study showed no difference in contact pressure, mean failure load, or gap formation with a standard suture bridge with knots tied at the medial row compared with knotless repairs. The results of this systematic review and quantitative synthesis indicate that the biomechanical factors ultimate load, stiffness, gap formation, and contact area are significantly improved when medial knots are tied as part of a transosseous-equivalent suture bridge construct compared with knotless constructs. Further studies comparing the clinical healing rates and functional outcomes between medial knotted and knotless repair techniques are needed. This review indicates that biomechanical factors are improved when the medial row of a transosseous-equivalent rotator cuff is tied compared with a knotless repair. However, this has not been definitively proven to translate to improved healing rates clinically. Copyright © 2013 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  17. Quantum communication under channel uncertainty

    International Nuclear Information System (INIS)

    Noetzel, Janis Christian Gregor

    2012-01-01

    This work contains results concerning transmission of entanglement and subspaces as well as generation of entanglement in the limit of arbitrary many uses of compound- and arbitrarily varying quantum channels (CQC, AVQC). In both cases, the channel is described by a set of memoryless channels. Only forward communication between one sender and one receiver is allowed. A code is said to be ''good'' only, if it is ''good'' for every channel out of the set. Both settings describe a scenario, in which sender and receiver have only limited channel knowledge. For different amounts of information about the channel available to sender or receiver, coding theorems are proven for the CQC. For the AVQC, both deterministic and randomised coding schemes are considered. Coding theorems are proven, as well as a quantum analogue of the Ahlswede-dichotomy. The connection to zero-error capacities of stationary memoryless quantum channels is investigated. The notion of symmetrisability is defined and used for both classes of channels.

  18. VAX CAMAC channel

    International Nuclear Information System (INIS)

    Nelson, D.J.; Breidenbach, M.; Granieri, C.D.; Grund, J.E.; Patrick, J.F.; Weaver, L.J.

    1980-10-01

    A new generation CAMAC System has been developed for the Mark II Detector at SLAC's PEP storage ring. This flexible system can efficiently transfer data between a host computer and a very large set of CAMAC data acquisition and control modules. A bipolar microprocessor operates as a Channel interface by supervising the CAMAC system and minimizing the host computer's work. This programmable channel couples the host to a set of System Crates; each System Crate houses Branch Drivers that can directly control a set of crates or communicate over differential parallel highways to Branch Receivers for control of distant crates. A coherent software package integrates the high level programs, system driver level programs, and microcode control of the system

  19. Geysering in boiling channels

    Energy Technology Data Exchange (ETDEWEB)

    Aritomi, Masanori; Takemoto, Takatoshi [Tokyo Institute of Technology, Tokyo (Japan); Chiang, Jing-Hsien [Japan NUS Corp. Ltd., Toyko (Japan)] [and others

    1995-09-01

    A concept of natural circulation BWRs such as the SBWR has been proposed and seems to be promising in that the primary cooling system can be simplified. The authors have been investigating thermo-hydraulic instabilities which may appear during the start-up in natural circulation BWRs. In our previous works, geysering was investigated in parallel boiling channels for both natural and forced circulations, and its driving mechanism and the effect of system pressure on geysering occurrence were made clear. In this paper, geysering is investigated in a vertical column and a U-shaped vertical column heated in the lower parts. It is clarified from the results that the occurrence mechanism of geysering and the dependence of system pressure on geysering occurrence coincide between parallel boiling channels in circulation systems and vertical columns in non-circulation systems.

  20. Coolant channel module CCM

    International Nuclear Information System (INIS)

    Hoeld, Alois

    2007-01-01

    A complete and detailed description of the theoretical background of an '(1D) thermal-hydraulic drift-flux based mixture-fluid' coolant channel model and its resulting module CCM will be presented. The objective of this module is to simulate as universally as possible the steady state and transient behaviour of the key characteristic parameters of a single- or two-phase fluid flowing within any type of heated or non-heated coolant channel. Due to the possibility that different flow regimes can appear along any channel, such a 'basic (BC)' 1D channel is assumed to be subdivided into a number of corresponding sub-channels (SC-s). Each SC can belong to only two types of flow regime, an SC with just a single-phase fluid, containing exclusively either sub-cooled water or superheated steam, or an SC with a two-phase mixture flow. After an appropriate nodalisation of such a BC (and therefore also its SC-s) a 'modified finite volume method' has been applied for the spatial discretisation of the partial differential equations (PDE-s) which represent the basic conservation equations of thermal-hydraulics. Special attention had to be given to the possibility of variable SC entrance or outlet positions (which describe boiling boundaries or mixture levels) and thus the fact that an SC can even disappear or be created anew. The procedure yields for each SC type (and thus the entire BC), a set of non-linear ordinary 1st order differential equations (ODE-s). To link the resulting mean nodal with the nodal boundary function values, both of which are present in the discretised differential equations, a special quadratic polygon approximation procedure (PAX) had to be constructed. Together with the very thoroughly tested packages for drift-flux, heat transfer and single- and two-phase friction factors this procedure represents the central part of the here presented 'Separate-Region' approach, a theoretical model which provides the basis to the very effective working code package CCM

  1. Tourism distribution channels

    OpenAIRE

    Camilleri, Mark Anthony

    2017-01-01

    The distribution channels link the customers with the businesses. For many years, the tourism businesses may have distributed their products and services through intermediaries. However, the latest advances in technology have brought significant changes in this regard. More individuals and corporate customers are increasingly benefiting of ubiquitous technologies, including digital media. The development of mobile devices and their applications, are offering a wide range of possibilities to t...

  2. Athermal channeled spectropolarimeter

    Science.gov (United States)

    Jones, Julia Craven

    2015-12-08

    A temperature insensitive (athermal) channeled spectropolarimeter (CSP) is described. The athermal CSP includes a crystal retarder formed of a biaxial crystal. The crystal retarder has three crystal axes, wherein each axis has its own distinct index of refraction. The axes are oriented in a particular manner, causing an amplitude modulating carrier frequency induced by the crystal retarder to be thermally invariant. Accordingly, a calibration beam technique can be used over a relatively wide range of ambient temperatures, with a common calibration data set.

  3. Nuclear reactor coolant channels

    International Nuclear Information System (INIS)

    Macbeth, R.V.

    1978-01-01

    A nuclear reactor coolant channel is described that is suitable for sub-cooled reactors as in pressurised water reactors as well as for bulk boiling, as in boiling water reactors and steam generating nuclear reactors. The arrangement aims to improve heat transfer between the fuel elements and the coolant. Full constructional details are given. See also other similar patents by the author. (U.K.)

  4. The M2 Channel

    DEFF Research Database (Denmark)

    Santner, Paul

    Drug resistance of Influenza A against antivirals is an increasing problem. No effective Influenza A drugs targeting the crucial viral protein, the proton transporter M2 are available anymore due to widespread resistance. Thanks to research efforts elucidating M2 protein structure, function and i...... resistance escape routes from drug inhibition. We thereby were hopefully able to provide a platform for the large-scale evaluation of M2 channel activity, inhibitors and resistance....

  5. Aquaglyceroporins: generalized metalloid channels

    Science.gov (United States)

    Mukhopadhyay, Rita; Bhattacharjee, Hiranmoy; Rosen, Barry P.

    2014-01-01

    Background: Aquaporins (AQPs), members of a superfamily of transmembrane channel proteins, are ubiquitous in all domains of life. They fall into a number of branches that can be functionally categorized into two major sub-groups: i) orthodox aquaporins, which are water-specific channels, and ii) aquaglyceroporins, which allow the transport of water, non-polar solutes, such as urea or glycerol, the reactive oxygen species hydrogen peroxide, and gases such as ammonia, carbon dioxide and nitric oxide and, as described in this review, metalloids. Scope of Review: This review summarizes the key findings that AQP channels conduct bidirectional movement of metalloids into and out of cells. Major Conclusions: As(OH)3 and Sb(OH)3 behave as inorganic molecular mimics of glycerol, a property that allows their passage through AQP channels. Plant AQPs also allow the passage of boron and silicon as their hydroxyacids, boric acid (B(OH)3) and orthosilicic acid (Si(OH)4), respectively. Genetic analysis suggests that germanic acid (GeO2) is also a substrate. While As(III), Sb(III) and Ge(IV) are toxic metalloids, borate (B(III)) and silicate (Si(IV)) are essential elements in higher plants. General Significance: The uptake of environmental metalloids by aquaporins provides an understanding of (i) how toxic elements such as arsenic enter the food chain; (ii) the delivery of arsenic and antimony containing drugs in the treatment of certain forms of leukemia and chemotherapy of diseases caused by pathogenic protozoa; and (iii) the possibility that food plants such as rice could be made safer by genetically modifying them to exclude arsenic while still accumulating boron and silicon. PMID:24291688

  6. Matching Dyadic Distributions to Channels

    OpenAIRE

    Böcherer, Georg; Mathar, Rudolf

    2010-01-01

    Many communication channels with discrete input have non-uniform capacity achieving probability mass functions (PMF). By parsing a stream of independent and equiprobable bits according to a full prefix-free code, a modu-lator can generate dyadic PMFs at the channel input. In this work, we show that for discrete memoryless channels and for memoryless discrete noiseless channels, searching for good dyadic input PMFs is equivalent to minimizing the Kullback-Leibler distance between a dyadic PMF ...

  7. Radar channel balancing with commutation

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin Walter

    2014-02-01

    When multiple channels are employed in a pulse-Doppler radar, achieving and maintaining balance between the channels is problematic. In some circumstances the channels may be commutated to achieve adequate balance. Commutation is the switching, trading, toggling, or multiplexing of the channels between signal paths. Commutation allows modulating the imbalance energy away from the balanced energy in Doppler, where it can be mitigated with filtering.

  8. Microstructural information from channeling measurements

    International Nuclear Information System (INIS)

    Quere, Y.

    1984-09-01

    Channeling is sensitive to nearly all structural changes in solids. One briefly recalls how particles are dechanneled by lattice defects and describes the main applications of channeling to materials science: detection of radiation damage, location of impurity atoms, precipitations in alloys... Channeling being a phenomenon characteristic of perfect crystals, any type of lattice imperfection (phonons, crystal defects, precipitation etc.) is expected to produce dechanneling. Consequently channeling and its opposite, dechanneling, have both been used to study structure and structural changes of materials

  9. Bow tie methodology: a tool to enhance the visibility and understanding of nuclear safety cases

    International Nuclear Information System (INIS)

    Vannerem, Marc

    2013-01-01

    There is much common ground between the nuclear industry and other major hazard industries such as those subject to the Seveso II regulations, e.g. oil, gas and chemicals. They are all subject to legal requirements to identify and control hazards, and to demonstrate that all necessary measures have been taken to minimise risks posed by the site with regard to people and the environment. This places a requirement on the Operators of major hazard installations, whether nuclear or conventional, to understand and identify the hazards of their operations, the initiating events, the consequences, the prevention and mitigation measures. However, in the UK, nuclear and 'Seveso' type facilities seem to adopt a different approach to the presentation of their safety cases. Given the magnitude of the hazards, safety cases developed for nuclear fuel cycle facilities are rigorous, detailed and complex, which can have the effect of reducing the visibility of the key hazards and corresponding protective measures. In contrast, on installations in the oil and gas and chemical industries, a real attempt has been made over recent years to improve the visibility and accessibility of the safety case to all operating personnel, through the use of visual aids / diagrams. In particular, many Operators are choosing to use 'bow tie methodology', in which very simple overview diagrams are produced to illustrate, in a form understandable by all: - what the key hazards are; - the initiating events; - the consequences of an incident; - the barriers or 'Layers of Protection' which prevent an initiating event from developing into an incident; - the barriers or 'Layers of Defence' which mitigate the consequences of an incident, i.e. which prevent the incident from escalating into major consequences. The bow tie method is one of a number of methodologies that can be used to make safety cases more accessible. It is used in this paper to illustrate ways to

  10. Application of ‘tying, binding and fixing operation’ in surgical treatment of severe mixed hemorrhoids

    Science.gov (United States)

    Huang, Hong-Xiang; Yao, Yi-Bo; Tang, Ying

    2016-01-01

    The aim of the present study was to examine the clinical value of ‘tying, binding and fixing operation’ in treating severe mixed hemorrhoids. A total of 160 patients with severe mixed hemorrhoids were selected and randomly divided into the experimental (n=80) and control (n=80) groups. The groups were treated using ‘tying, binding and fixing operation’ and Doppler ultrasound-guided hemorrhoidal artery ligation (DG-HAL), respectively. The results showed that the average operative time of the experimental group (35.57±6.17) was significantly higher than that of the control group (12.73±4.92). There was no significant difference of blood loss during the operation between the two groups (P>0.05). There was also no significant difference in improving the hemorrhage symptom between the two groups (P>0.05). In addition, concerning improvement of prolapse symptoms and reduction of the volume of hemorrhoids, the experimental group were significantly improved as compared to the control group. No anal function damage in the two groups was identified, and the length of stay in hospital for the two groups was not significantly different (P>0.05). However, the hospitalization cost in the experimental group (5,334.77±875.54) was significantly lower than that of the control group (8,551.81±1,806.54) and satisfaction degree was significantly higher than that of the control group. The incidences of perianal pain, anal edema and dysuria between two groups were not significantly different (P>0.05). There were 10 cases of secondary hemorrhage and 18 cases of infection in the experimental group, and 12 cases of secondary hemorrhage and 14 cases of infection in the control group, although the differences between the two groups were not statistically significant (P>0.05). The incidence rate of local hematoma in the experimental group (1.2%) was significantly lower than that in the control group (15.0%). The recurrence rate of the control group (22.5%) was also significantly

  11. Rural-urban migration in Zambia and migrant ties to home villages.

    Science.gov (United States)

    Ogura, M

    1991-06-01

    Rural to urban migration patterns in Zambia and migrant ties to home villages are discussed 1st in terms of a statistical overview of migration and urbanization, and followed by an examination of lengthening stays in towns and ties to the home village based on other studies and the author's field research and random sampling in 6 urban areas of Zambia. The primary population centers are the copperbelt which comprises 45% of the total urban population, and Lusaka which is 24% of the total urban population. 31% of the total population reside in Lusaka, 7 mining towns, Kabwe, and Livingstone. Migration and a high rate of natural population growth are responsible for the urban growth. Recent economic difficulties have reduced the flow of migration to urban areas and lead to the out migration in copper towns. independence also has had an effect on migration, such that female migration increased along with male migration. Female migration reflects female educational advances and the changing practice of housewives accompanying husbands. The informal sector absorbs a great number of the migrant labor force. Income gaps between urban and rural areas also contribute to migration flows. Other magnets in urban areas are better educational opportunities, a water supply, and the lure of city lights. Since independence, migrants have increased their length of stay in towns but continue to maintain links with their home villages. 87.5% of mine workers are estimated as intending to go back to their villages. Before the mid-1970s it is estimated in a Ngombe squatter camp that 65% of employed male household heads had sent money home the prior year, 58% had visited home within the past 5 years, but 25% had never visited in 10 years. 58% intended to return home and 36% intended to stay permanently. The author's research between 1987-89 found 3 types of squatter villages: those retired and not returning to home villages such as Kansusuwa, those workers living in compounds where farm

  12. Terahertz-wave near-field imaging with subwavelength resolution using surface-wave-assisted bow-tie aperture

    Science.gov (United States)

    Ishihara, Kunihiko; Ohashi, Keishi; Ikari, Tomofumi; Minamide, Hiroaki; Yokoyama, Hiroyuki; Shikata, Jun-ichi; Ito, Hiromasa

    2006-11-01

    We demonstrate the terahertz-wave near-field imaging with subwavelength resolution using a bow-tie shaped aperture surrounded by concentric periodic structures in a metal film. A subwavelength aperture with concentric periodic grooves, which are known as a bull's eye structure, shows extremely large enhanced transmission beyond the diffraction limit caused by the resonant excitation of surface waves. Additionally, a bow-tie aperture exhibits extraordinary field enhancement at the sharp tips of the metal, which enhances the transmission and the subwavelength spatial resolution. We introduced a bow-tie aperture to the bull's eye structure and achieved high spatial resolution (˜λ/17) in the near-field region. The terahertz-wave near-field image of the subwavelength metal pattern (pattern width=20μm) was obtained for the wavelength of 207μm.

  13. Building Social Capital: How the news and the strength of the ties in the political discussion foster reciprocity

    Directory of Open Access Journals (Sweden)

    Alberto Ardèvol-Abreu

    2018-03-01

    Full Text Available Reciprocity, a social principle that emerges in non-negotiated, inter-personal exchange, is arguably a key construct in generating social capital. However, little research has made this empirical connection. Building on an Orientation-Stimulus-Reasoning-Orientation-Response model, this study advances a theoretical and empirical model in which news use and political discussion tie strength contributes to the development of reciprocity and social capital. Drawing on two-wave panel data, results suggest that reciprocity is a strong predictor of social capital. News media use also directly predicts reciprocity, as well as political discussion with both strong and weak ties, and social capital. Additionally, discussion with weak ties and reciprocity mediate the relationship between news use and social capital.

  14. Ion channeling revisited

    Energy Technology Data Exchange (ETDEWEB)

    Doyle, Barney Lee [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Corona, Aldo [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Nguyen, Anh [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-09-01

    A MS Excel program has been written that calculates accidental, or unintentional, ion channeling in cubic bcc, fcc and diamond lattice crystals or polycrystalline materials. This becomes an important issue when simulating the creation by energetic neutrons of point displacement damage and extended defects using beams of ions. All of the tables and graphs in the three Ion Beam Analysis Handbooks that previously had to be manually looked up and read from were programed into Excel in handy lookup tables, or parameterized, for the case of the graphs, using rather simple exponential functions with different powers of the argument. The program then offers an extremely convenient way to calculate axial and planar half-angles and minimum yield or dechanneling probabilities, effects on half-angles of amorphous overlayers, accidental channeling probabilities for randomly oriented crystals or crystallites, and finally a way to automatically generate stereographic projections of axial and planar channeling half-angles. The program can generate these projections and calculate these probabilities for axes and [hkl] planes up to (555).

  15. The alpha channeling effect

    Science.gov (United States)

    Fisch, N. J.

    2015-12-01

    Alpha particles born through fusion reactions in a tokamak reactor tend to slow down on electrons, but that could take up to hundreds of milliseconds. Before that happens, the energy in these alpha particles can destabilize on collisionless timescales toroidal Alfven modes and other waves, in a way deleterious to energy confinement. However, it has been speculated that this energy might be instead be channeled into useful energy, so as to heat fuel ions or to drive current. Such a channeling needs to be catalyzed by waves Waves can produce diffusion in energy of the alpha particles in a way that is strictly coupled to diffusion in space. If these diffusion paths in energy-position space point from high energy in the center to low energy on the periphery, then alpha particles will be cooled while forced to the periphery. The energy from the alpha particles is absorbed by the wave. The amplified wave can then heat ions or drive current. This process or paradigm for extracting alpha particle energy collisionlessly has been called alpha channeling. While the effect is speculative, the upside potential for economical fusion is immense. The paradigm also operates more generally in other contexts of magnetically confined plasma.

  16. TRP channels in kidney disease.

    NARCIS (Netherlands)

    Hsu, Y.J.; Hoenderop, J.G.J.; Bindels, R.J.M.

    2007-01-01

    Mammalian TRP channel proteins form six-transmembrane cation-permeable channels that may be grouped into six subfamilies on the basis of amino acid sequence homology (TRPC, TRPV, TRPM, TRPA, TRPP, and TRPML). Recent studies of TRP channels indicate that they are involved in numerous fundamental cell

  17. Parallel inter channel interaction mechanisms

    International Nuclear Information System (INIS)

    Jovic, V.; Afgan, N.; Jovic, L.

    1995-01-01

    Parallel channels interactions are examined. For experimental researches of nonstationary regimes flow in three parallel vertical channels results of phenomenon analysis and mechanisms of parallel channel interaction for adiabatic condition of one-phase fluid and two-phase mixture flow are shown. (author)

  18. A new technique to characterize CT scanner bow-tie filter attenuation and applications in human cadaver dosimetry simulations

    Science.gov (United States)

    Li, Xinhua; Shi, Jim Q.; Zhang, Da; Singh, Sarabjeet; Padole, Atul; Otrakji, Alexi; Kalra, Mannudeep K.; Xu, X. George; Liu, Bob

    2015-01-01

    Purpose: To present a noninvasive technique for directly measuring the CT bow-tie filter attenuation with a linear array x-ray detector. Methods: A scintillator based x-ray detector of 384 pixels, 307 mm active length, and fast data acquisition (model X-Scan 0.8c4-307, Detection Technology, FI-91100 Ii, Finland) was used to simultaneously detect radiation levels across a scan field-of-view. The sampling time was as short as 0.24 ms. To measure the body bow-tie attenuation on a GE Lightspeed Pro 16 CT scanner, the x-ray tube was parked at the 12 o’clock position, and the detector was centered in the scan field at the isocenter height. Two radiation exposures were made with and without the bow-tie in the beam path. Each readout signal was corrected for the detector background offset and signal-level related nonlinear gain, and the ratio of the two exposures gave the bow-tie attenuation. The results were used in the geant4 based simulations of the point doses measured using six thimble chambers placed in a human cadaver with abdomen/pelvis CT scans at 100 or 120 kV, helical pitch at 1.375, constant or variable tube current, and distinct x-ray tube starting angles. Results: Absolute attenuation was measured with the body bow-tie scanned at 80–140 kV. For 24 doses measured in six organs of the cadaver, the median or maximum difference between the simulation results and the measurements on the CT scanner was 8.9% or 25.9%, respectively. Conclusions: The described method allows fast and accurate bow-tie filter characterization. PMID:26520720

  19. I.Kanta idejas un to ietekme uz mūsdienu tiesību attīstību

    OpenAIRE

    Smiltēna, Anda

    2007-01-01

    Darbs ir veltīts Imanuela Kanta tiesību filozofijas analīzei, uzmanību pievēršot tiesību teorijas jautājumiem, kā arī šo ideju praktiskajai ietekmei mūsdienu tiesību zinātnē. Pirmajā nodaļā aprakstītas galvenās Kanta tiesību filozofijas idejas, kas veido tiesību teorijas bāzi, nosaka tiesību sistēmu un to veidojošo elementu īpašības, nodala tiesības no morāles, iezīmē kategoriskā imperatīva un brīvības kategorijas nozīmi tiesībās. Otrā nodaļa veltīta neokantisma kustībai tiesībās un tās galve...

  20. TH-CD-207B-05: Measurement of CT Bow-Tie Profiles Using a Linear Array Detector

    Energy Technology Data Exchange (ETDEWEB)

    Yang, K; Li, X; Liu, B [Massachusetts General Hospital, Boston, MA (United States)

    2016-06-15

    Purpose: To accurately measure CT bow-tie profiles from various manufacturers and to provide non-proprietary information for CT system modeling. Methods: A GOS-based linear detector (0.8 mm per pixel and 51.2 cm in length) with a fast data sampling speed (0.24 ms/sample) was used to measure the relative profiles of bow-tie filters from a collection of eight CT scanners by three different vendors, GE (LS Xtra, LS VCT, Discovery HD750), Siemens (Sensation 64, Edge, Flash, Force), and Philips (iBrilliance 256). The linear detector was first calibrated for its energy response within typical CT beam quality ranges and compared with an ion chamber and analytical modeling (SPECTRA and TASMIP). A geometrical calibration process was developed to determine key parameters including the distance from the focal spot to the linear detector, the angular increment of the gantry at each data sampling, the location of the central x-ray on the linear detector, and the angular response of the detector pixel. Measurements were performed under axial-scan modes for most representative bow-tie filters and kV selections from each scanner. Bow-tie profiles were determined by re-binning the measured rotational data with an angular accuracy of 0.1 degree using the calibrated geometrical parameters. Results: The linear detector demonstrated an energy response as a solid state detector, which is close to the CT imaging detector. The geometrical calibration was proven to be sufficiently accurate (< 1mm in error for distances >550 mm) and the bow-tie profiles measured from rotational mode matched closely to those from the gantry-stationary mode. Accurate profiles were determined for a total of 21 bow-tie filters and 83 filter/kV combinations from the abovementioned scanner models. Conclusion: A new improved approach of CT bow-tie measurement was proposed and accurate bow-tie profiles were provided for a broad list of CT scanner models.

  1. The Ties That Bind: Midlife Parents' Daily Experiences With Grown Children.

    Science.gov (United States)

    Fingerman, Karen L; Kim, Kyungmin; Birditt, Kira S; Zarit, Steven H

    2016-04-01

    Daily pleasant or stressful experiences with grown children may contribute to parental well-being. This diary study focused on midlife parents' ( N = 247) reports regarding grown children for 7 days. Nearly all parents (96%) had contact with a child that week via phone, text, or in person. Nearly all parents shared laughter or enjoyable interactions with grown children during the study week. More than half of parents experienced stressful encounters (e.g., child got on nerves) or stressful thoughts about grown children (e.g., worrying, fretting about a problem). Pleasant and stressful experiences with grown children were associated with parents' positive and negative daily moods. A pleasant experience with a grown child the same day as a stressful experience mitigated effects of those stressful experiences on negative mood, however. The findings have implications for understanding intergenerational ambivalence and stress buffering in this tie.

  2. The Ties That Bind: Midlife Parents’ Daily Experiences With Grown Children

    Science.gov (United States)

    Fingerman, Karen L.; Kim, Kyungmin; Birditt, Kira S.; Zarit, Steven H.

    2015-01-01

    Daily pleasant or stressful experiences with grown children may contribute to parental well-being. This diary study focused on midlife parents’ (N = 247) reports regarding grown children for 7 days. Nearly all parents (96%) had contact with a child that week via phone, text, or in person. Nearly all parents shared laughter or enjoyable interactions with grown children during the study week. More than half of parents experienced stressful encounters (e.g., child got on nerves) or stressful thoughts about grown children (e.g., worrying, fretting about a problem). Pleasant and stressful experiences with grown children were associated with parents’ positive and negative daily moods. A pleasant experience with a grown child the same day as a stressful experience mitigated effects of those stressful experiences on negative mood, however. The findings have implications for understanding intergenerational ambivalence and stress buffering in this tie. PMID:27022198

  3. The large scale use of strippable coatings in preventative, tie-down and decontamination applications

    International Nuclear Information System (INIS)

    Sanders, M.J.; Pengelly, M.G.A.

    1985-05-01

    The use of strippable coatings both to remove and prevent the radioactive contamination of equipment is discussed. Details of application by brush, roller, conventional (air) and airless spray are given. The use of strippable coatings to prevent the components of a re-useable temporary containment system from becoming contaminated is described and results of simple tests in which the coatings were used to remove plutonium dioxide contamination from a number of different surfaces in a Pressurised Suit Area are given. It is concluded that strippable coatings are particularly useful in contamination prevention and tie-down roles but test results indicate that they do not possess overwhelming advantages when used as a decontamination technique. The products used in the work reported here are water based. (author)

  4. In stressful company – Changes in stress and work ties over time

    DEFF Research Database (Denmark)

    Waldstrøm, Christian; Parker, Andrew; Shah, Neha P.

    Recent research on stress and burnout has highlighted the collective aspects of stress symptoms, perceived stress, and coping mechanisms. Much of this work, however, is focused on group and team dynamics rather than how network factors shape individuals’ feelings of stress and burnout. We use...... a stress questionnaire and social network analysis at three time points in a Scandinavian biotechnology company to examine the interactions between stress and relationship development and maintenance over time. We show that individuals tend to form and maintain ties to people who are less stressed than...... they are, indicating that while misery might love company, stress does not. Given the longitudinal nature of the study, we’re able to disentangle the causal effects....

  5. Tie-1-directed expression of Cre recombinase in endothelial cells of embryoid bodies and transgenic mice

    DEFF Research Database (Denmark)

    Gustafsson, E; Brakebusch, C; Hietanen, K

    2001-01-01

    Tissue-specific gene inactivation using the Cre-loxP system has become an important tool to unravel functions of genes when the conventional null mutation is lethal. We report here the generation of a transgenic mouse line expressing Cre recombinase in endothelial cells. In order to avoid...... the production and screening of multiple transgenic lines we used embryonic stem cell and embryoid body technology to identify recombinant embryonic stem cell clones with high, endothelial-specific Cre activity. One embryonic stem cell clone that showed high Cre activity in endothelial cells was used to generate...... germline chimeras. The in vivo efficiency and specificity of the transgenic Cre was analysed by intercrossing the tie-1-Cre line with the ROSA26R reporter mice. At initial stages of vascular formation (E8-9), LacZ staining was detected in almost all cells of the forming vasculature. Between E10 and birth...

  6. Application of Coordinated SOFC and SMES Robust Control for Stabilizing Tie-Line Power

    Energy Technology Data Exchange (ETDEWEB)

    Ning Zhang; Wei Gu; Haojun Yu; Wei Liu [School of Electrical Engineering, Southeast University, Nanjing (China)

    2013-04-15

    Wind power causes fluctuations in power systems and introduces issues concerning system stability and power quality because of the lack of controllability of its discontinuous and intermittent resources. This paper presents a coordinated control strategy for solid oxide fuel cells (SOFCs) and superconducting magnetic energy storage (SMES) to match the intermittent wind power generation and compensate for the rapid load changes. An optimal H{sub {infinity}}control method, where the weighting function selection is expressed as an optimization problem, is proposed to mitigate tie-line power fluctuations and the mixed-sensitivity approach is used to deal with the interference suppression. Simulation results show that the proposed method significantly improves the smoothing effect of wind power fluctuations. Compared with the conventional control method, the proposed method has better anti-interference performance in various operating situations.

  7. Creosote released from railway-ties recycled and the sanitary risks.

    Science.gov (United States)

    Zicari, Giuseppe; Allegro, Giuseppe; Russo, Domenico; Rivetti, Daniela; Soardo, Vincenzo; Cerrato, Elena

    2013-01-01

    Through the history of railways, wooden crossties impregnated with potentially hazardous creosote tar, have been used for years. There are six major classes of compounds in the creosote: aromatic hydrocarbons; tar acids/phenolics; tar bases/nitrogen-containing heterocycles; aromatic amines; sulfur-containing heterocycles; and oxygen-containing heterocycles. The creosote molecules applied in railway crossties can be released in the environment and they can bioaccumulate in animals and vegetables. Some constituents (benzo(a)pyrene and phenolics like benzene) are considered as being carcinogenic which renders the entire complex of creosote to be classified as potentially carcinogenic. After several decades of use the railway-ties are been recycled for varies uses like fences, stakes for agriculture and fruit production or bank protection. In this paper are examined some environmental and sanitary risks from wood impregnated with creosote reported in the literature.

  8. The strength-of-weak-ties perspective on creativity: a comprehensive examination and extension.

    Science.gov (United States)

    Baer, Markus

    2010-05-01

    Disentangling the effects of weak ties on creativity, the present study separated, both theoretically and empirically, the effects of the size and strength of actors' idea networks and examined their joint impact while simultaneously considering the separate, moderating role of network diversity. I hypothesized that idea networks of optimal size and weak strength were more likely to boost creativity when they afforded actors access to a wide range of different social circles. In addition, I examined whether the joint effects of network size, strength, and diversity on creativity were further qualified by the openness to experience personality dimension. As expected, results indicated that actors were most creative when they maintained idea networks of optimal size, weak strength, and high diversity and when they scored high on the openness dimension. The implications of these results are discussed. PsycINFO Database Record (c) 2010 APA, all rights reserved.

  9. [From one generation to another, the threats of the disintegration of social ties].

    Science.gov (United States)

    Blondel, Frédéric; Delzescaux, Sabine

    2010-01-01

    In our modern societies, social ties are reflected in three forms of social relationships which merge with each other: social norms, local social networks and relationships within families. In times of abundance these three forms tend to lead to the same ethical attitude towards elderly and dependent people. Each agrees on the importance of providing a level of care which guarantees elderly people a state of well-being which we would all like to enjoy ourselves. In times of crisis however these three forms tend to fall out of synch with each other as the expectations of one can contradict those of another. What are the risks of such a de-synchronisation in the support given to elderly people?

  10. Oxidation of graphene 'bow tie' nanofuses for permanent, write-once-read-many data storage devices.

    Science.gov (United States)

    Pearson, A C; Jamieson, S; Linford, M R; Lunt, B M; Davis, R C

    2013-04-05

    We have fabricated nanoscale fuses from CVD graphene sheets with a 'bow tie' geometry for write-once-read-many data storage applications. The fuses are programmed using thermal oxidation driven by Joule heating. Fuses that were 250 nm wide with 2.5 μm between contact pads were programmed with average voltages and powers of 4.9 V and 2.1 mW, respectively. The required voltages and powers decrease with decreasing fuse sizes. Graphene shows extreme chemical and electronic stability; fuses require temperatures of about 400 °C for oxidation, indicating that they are excellent candidates for permanent data storage. To further demonstrate this stability, fuses were subjected to applied biases in excess of typical read voltages; stable currents were observed when a voltage of 10 V was applied to the devices in the off state and 1 V in the on state for 90 h each.

  11. Research on the network structure of the urban economic ties in Shanghai

    Directory of Open Access Journals (Sweden)

    CHEN Wenyan

    2015-04-01

    Full Text Available Assessing the network structure of the urban economic ties (NSUET of a city can help us understand its development level.Using the gravity model,the social network analysis method and the Arcgis tool,this paper has done some researches about the NSUET in Shanghai.The research results show that the NSUET in Shanghai was improved gradually from 2000 to 2010 and is in a stable status now.In the future,the NSUET in Shanghai should be adjusted to meet the need of urban development;the more focuses should be placed on the districts with better infrastructure,while the other areas are also considered to develop the NSUET.

  12. Application of TIE's in assessing toxicity associated with oil sands process waters

    International Nuclear Information System (INIS)

    MacKinnon, M.

    1998-01-01

    The hot water digestion process which separates bitumen from oil sands produces large volumes of process-affected waters which are extremely toxic to aquatic organisms. At Syncrude Canada's northeastern Alberta plant, the toxic waters are contained on the site and none are discharged. Organic acids, hydrocarbons and salts are leached into the tailings waters. A toxicity identification evaluation (TIE) test was used to confirm the main contributors to the acute toxicity in these waters. A battery bioassay approach as well as field and laboratory testing was used to understand the source, pathway and duration of the toxicity. Bioassays helped in developing ways in which to mitigate toxicity issues in both reclamation and operational waters. It was demonstrated that natural bioremediation of process-affected waters can reduce acute and chronic toxicity. The long term reclamation impacts of these waters has yet to be determined

  13. Public Response to Residential Grid-Tied PV Systems in Colorado: A Qualitative Market Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Farhar, Barbara C. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Buhrmann, Jan [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    1998-07-01

    The early adopters of residential grid-tied photovoltaics (PV) have complex motivations to pay today's costs, including altruistic, environmental, and financial reasons. Focused interviews were conducted with a self-selected purposive sample interested in purchasing 2-kW or 3-kW PV systems with an installed cost of $8,000 to $12,000. The sample tended to be men or married couples ranging in age from their early thirties to their mid-eighties; professionals, managers, or small business owners; relatively financially secure, with experience with energy efficiency and renewable energy. Product attributes they preferred were net metering, warranties, guarantees, utility financing, maintenance, an option to own or lease, a battery option, and an aesthetically pleasing system. Potential PV customers needed more information before making a purchase decision.

  14. Application of Coordinated SOFC and SMES Robust Control for Stabilizing Tie-Line Power

    Directory of Open Access Journals (Sweden)

    Wei Liu

    2013-04-01

    Full Text Available Wind power causes fluctuations in power systems and introduces issues concerning system stability and power quality because of the lack of controllability of its discontinuous and intermittent resources. This paper presents a coordinated control strategy for solid oxide fuel cells (SOFCs and superconducting magnetic energy storage (SMES to match the intermittent wind power generation and compensate for the rapid load changes. An optimal H∞ control method, where the weighting function selection is expressed as an optimization problem, is proposed to mitigate tie-line power fluctuations and the mixed-sensitivity approach is used to deal with the interference suppression. Simulation results show that the proposed method significantly improves the smoothing effect of wind power fluctuations. Compared with the conventional control method, the proposed method has better anti-interference performance in various operating situations.

  15. The design and development of a spacecraft appendage tie down mechanism

    Science.gov (United States)

    Nygren, W. D.; Head, R.

    1985-01-01

    The design and evolution is described of a spacecraft Appendage Tie Down Mechanism (ATDM). Particular emphasis is paid to the mechanical aspects of using dry lubricants to increase the efficiency of acme threads and worm gearing. The ATDM consists of five major components. These are a dc torque motor, a worm gear speed reducer, the tension bolt (or T-bolt), nut capture and centering jaws and the capture nut. In addition, there are several minor components such as limit switch assemblies and an antibackdrive mechanism which couples the drive motor to the worm shaft. A development model of the ATDM in various configurations was under test for some time. In its latest version, it has successfully completed thermal vacuum testing, vibration testing, and extended life testing.

  16. Kinship Ties: Attachment Relationships that Promote Resilience in African American Adult Children of Alcoholics

    Directory of Open Access Journals (Sweden)

    J. Camille Hall

    2007-05-01

    Full Text Available For many African Americans, the extended family has been the source of strength, resilience, and survival. Although changes in African American families, like changes in all families in the United States that have diluted the importance of kinship ties, many African Americans continue to place a high value on extended family members. Children of Africans and communities of African descent traditionally interact with multiple caregivers, consisting of kin, and fictive kin.Utilizing both attachment theory and risk and resilience literature, this paper discusses ways to better understand the resilient nature of African American families and how multiple attachment relationships assist at-risk African American children, specifically adult children of alcoholics (ACOAs.

  17. Technical specification for design, fabrication, use and maintenance of tie-down system

    International Nuclear Information System (INIS)

    Curcuruto, S.; Palmieri, G.; Trivelloni, S.; Orsini, A.

    1993-01-01

    IAEA Safety Series ndeg6 states that to ensure compliance with the Regulation the programs of quality assurance must be put in practice either for design, manufacture, testing, documentation, use and maintenance and inspection of all packages or for transport and intransit storage operations. Therefore in view of a standardization coming from Q.A. criteria, the Italian Competent Authority for transport of radioactive material (ENEA-DISP) is preparing a technical guide for the design, construction, use and maintenance of tie-down system for road transport of packages containing radioactive materials. The paper shows some phases of the program started by ENEA-DISP for the redaction of the technical guide. (J.P.N.)

  18. Close social ties and health in later life: Strengths and vulnerabilities.

    Science.gov (United States)

    Rook, Karen S; Charles, Susan T

    2017-09-01

    The world is aging at an unprecedented rate, with older adults representing the fastest-growing segment of the population in most economically developed and developing countries. This demographic shift leaves much uncharted territory for researchers who study social relationships and health. Social relationships exert powerful influences on physical health in later adulthood, a critical consideration given age-related increases in the prevalence of chronic health conditions and physical disability. A large body of research indicates that older adults report greater satisfaction with their social networks than do younger adults, and that they often take measures to minimize their exposure to negative social encounters. These emotionally satisfying and generally positive social ties afford some health protection against a backdrop of mounting physical limitations and play an important role when juxtaposed with the potentially health-damaging frictions that sometimes emerge in older adults' social relationships. Although most older adults report that they are satisfied with their social ties, some older adults experience frequent conflicts or ambivalent exchanges with members of their social networks, and these experiences detract from their health. In addition, many older adults will experience the loss of one or more close relationships during the course of their lives, with ramifications for their health and, often, for the reorganization of their social lives over time. Understanding how both the strengths and vulnerabilities of close social relationships affect health and well-being in later life is an important goal, particularly in view of the accelerating rate of population aging worldwide. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  19. Financial and Emotional Support in Close Personal Ties among Central Asian Migrant Women in Russia.

    Science.gov (United States)

    Kornienko, Olga; Agadjanian, Victor; Menjívar, Cecilia; Zotova, Natalia

    2018-05-01

    This study advances research on the role of personal networks as sources of financial and emotional support in immigrants' close personal ties beyond the immediate family. Because resource scarcity experienced by members of immigrant communities is likely to disrupt normatively expected reciprocal support, we explored multi-level predictors of exchange processes with personal network members that involve (1) only receiving support, (2) only providing support, and (3) reciprocal support exchanges. We focus on an understudied case of Central Asian migrant women in the Russian Federation using a sample of 607 women from three ethnic groups-Kyrgyz, Tajik, Uzbek-who were surveyed in two large Russian cities-Nizhny Novgorod and Kazan. The survey collected information on respondents' demographic, socioeconomic, and migration-related characteristics, as well as characteristics of up to five individuals with whom they had a close relationship. Multi-level multinomial regression analyses were used to account for the nested nature of the data. Our results revealed that closer social relationships (siblings and friends) and greater levels of resources (income and regularized legal status) at both ego and alter levels were positively related to providing, receiving, and reciprocally exchanging financial and emotional support. Egos were more likely to provide financial assistance to transnational alters, whereas they were more likely to engage in mutual exchanges of emotional support with their network members from other countries. Personal network size and density showed no relationship with support exchanges. These findings provide a nuanced picture of close personal ties as conduits for financial and emotional support in migrant communities in a major, yet understudied, migrant-receiving context.

  20. N isotopes and N cycle in the TieShanPing subtropical forest ecosystem, Southwestern China.

    Science.gov (United States)

    Jiang, Chun-lai; Zhang, Xiao-Shan

    2009-07-01

    Nitrogen is essential for forest growth and forest stand development. It is commonly a limited factor for forest productivity. We examined delta (15)N values in soils and plants by studying the sources of N used by vegetation and cycles of N in a 43-year-old plantation of the TieShanPing forest ecosystem in southwestern China, dominated by massone pine (Pinus massoniana). The N concentration of plant materials ranges from 1.1% to 2.2%. The nitrogen concentration of P. massoniana was 1.3% while soils showed the concentration of 0.04-0.15%. Regarding natural abundance of (15)N, large significant variation (-6.0 per thousand to -3.8 per thousand) in delta (15)N values was observed among shrub and tree leaves. delta (15)N values were also significantly varied from -4.7 per thousand to -3.8 per thousand among the pioneer species in the plantation. Soil delta (15)N values (3.1-6.3 per thousand) were significantly enriched compared to those values in plant samples. Despite the negative delta (15)N values of the vegetation cover, the high delta (15)N values in the topsoil indicate that return of N to soils by litter-fall is minimal on TieShanPing and the present forests do not change very much the soil (15)N signals at the surface layer. The positive delta (15)N values may also indicate large N losses from the soil system vial leaching, volatilization and plant uptake.

  1. Case study installation of a HDPE curtain wall with sheetpile tie-in on both ends

    International Nuclear Information System (INIS)

    Schindler, R.M.; Maltese, P.C.

    1997-01-01

    The plans for eliminating the off-site migration of non-aqueous phase liquid (NAPL) from a refinery into a nearby river included the installation of a High Density Polyethylene (HDPE) curtain wall and an underdrain system. A 640 m (2100 lineal feet) HDPE Curtain Wall was installed along the river boundary, tying into an existing sheet pile wall on both ends. The wall varied from approximately 4.5 m (15 feet) deep at the northern end to about 7 m (23 feet) deep at the southern end, running approximately 3 to 3.6 m (10 to 12 feet) inland of an existing wooden bulkhead. The curtain wall was successfully installed through a slurry supported trench. A 930 m (3050 lineal feet) interception/collection trench was installed parallel to the HDPE Curtain Wall, continuing on beyond the curtain wall on the southern end. The depth of the trench varied from approximately 3 to 4 m (10 to 13 feet) deep. A 20.32 cm (8 inch) diameter perforated HDPE header pipe was placed in the trench to convey groundwater and product to two sumps. The trench is 53.34 cm (21 inches) wide and contained aggregate to approximately 0.9 m (3 feet) below ground. This work was accomplished using the bio-polymer slurry drainage trench (BP Drain) technique. This paper briefly describes the construction methods utilized during this project, specifically HDPE curtain wall installation thru a bentonite slurry and tie-in to the existing sheet pile wall

  2. Cow comfort in tie-stalls: increased depth of shavings or straw bedding increases lying time.

    Science.gov (United States)

    Tucker, C B; Weary, D M; von Keyserlingk, M A G; Beauchemin, K A

    2009-06-01

    Over half of US dairy operations use tie-stalls, but these farming systems have received relatively little research attention in terms of stall design and management. The current study tested the effects of the amount of 2 bedding materials, straw and shavings, on dairy cattle lying behavior. The effects of 4 levels of shavings, 3, 9, 15, and 24 kg/stall (experiment 1, n = 12), and high and low levels of straw in 2 separate experiments: 1, 3, 5, and 7 kg/stall (experiment 2, n = 12) and 0.5, 1, 2, and 3 kg/stall (experiment 3, n = 12) were assessed. Treatments were compared using a crossover design with lactating cows housed in tie-stalls fitted with mattresses. Treatments were applied for 1 wk. Total lying time, number of lying bouts, and the length of each lying bout was recorded with data loggers. In experiment 1, cows spent 3 min more lying down for each additional kilogram of shavings (11.0, 11.7, 11.6, and 12.1 +/- 0.24 h/d for 3, 9, 15, and 24 kg/stall shavings, respectively). In experiment 2, cows increased lying time by 12 min for every additional kilogram of straw (11.2, 12.0, 11.8, and 12.4 +/- 0.24 h/d for 1, 3, 5, and 7 kg/stall of straw, respectively). There were no differences in lying behavior among the lower levels of straw tested in experiment 3 (11.7 +/- 0.32 h/d). These results indicated that additional bedding above a scant amount improves cow comfort, as measured by lying time, likely because a well-bedded surface is more compressible.

  3. Voltage-Gated Calcium Channels

    Science.gov (United States)

    Zamponi, Gerald Werner

    Voltage Gated Calcium Channels is the first comprehensive book in the calcium channel field, encompassing over thirty years of progress towards our understanding of calcium channel structure, function, regulation, physiology, pharmacology, and genetics. This book balances contributions from many of the leading authorities in the calcium channel field with fresh perspectives from risings stars in the area, taking into account the most recent literature and concepts. This is the only all-encompassing calcium channel book currently available, and is an essential resource for academic researchers at all levels in the areas neuroscience, biophysics, and cardiovascular sciences, as well as to researchers in the drug discovery area.

  4. Application of the Bow Tie method for evaluation of safety in the procedure of logging wells; Aplicacion del metodo de Bow Tie para la evaluacion de seguridad en la practica de perfilaje de pozos

    Energy Technology Data Exchange (ETDEWEB)

    Alfonso Pallares, C; Perez Reyes, Y.; Sarabia Molina, I.I. [Centro Nacional de Seguridad Nuclear (CNSN), La Habana (Cuba)

    2013-07-01

    This work consists of an assessment of security in the practice of logging of oil wells, using the method of Bow Tie for being a simple method of evaluation of the risk, which makes it possible in a structured way to set priorities to manage risk.

  5. Beyond the Manual Channel

    DEFF Research Database (Denmark)

    , the main focus there is on spoken languages in their written and spoken forms. This series of workshops, however, offers a forum for researchers focussing on sign languages. For the fourth time, the workshop had sign language corpora as its main topic. This time, the focus was on any aspect beyond...... the manual channel. Not surprisingly, most papers deal with non-manuals on the face. Once again, the papers at this workshop clearly identify the potentials of even closer cooperation between sign linguists and sign language engineers, and we think it is events like this that contribute a lot to a better...

  6. Ion Channels in Leukocytes

    Science.gov (United States)

    1991-07-01

    muscle k142), heart muscle (80), bo- are released. In recent years much has been learned vine pulmonar arter endothelial cells (251), and rat about the...b3 Zn or cytes from cystic fibrosis patients lack a Cl current that Ni (1 mM)-added to the cytoplasmic side of the mem- can be acti% ated b3 the...that at37’C hu- to be defectiv.- in cystic fibrosis (55, 277), and Chen et al. man T-cell CiL channels are active at rest, implies that (25) have shown

  7. A Micromechanical RF Channelizer

    Science.gov (United States)

    Akgul, Mehmet

    The power consumption of a radio generally goes as the number and strength of the RF signals it must process. In particular, a radio receiver would consume much less power if the signal presented to its electronics contained only the desired signal in a tiny percent bandwidth frequency channel, rather than the typical mix of signals containing unwanted energy outside the desired channel. Unfortunately, a lack of filters capable of selecting single channel bandwidths at RF forces the front-ends of contemporary receivers to accept unwanted signals, and thus, to operate with sub-optimal efficiency. This dissertation focuses on the degree to which capacitive-gap transduced micromechanical resonators can achieve the aforementioned RF channel-selecting filters. It aims to first show theoretically that with appropriate scaling capacitive-gap transducers are strong enough to meet the needed coupling requirements; and second, to fully detail an architecture and design procedure needed to realize said filters. Finally, this dissertation provides an actual experimentally demonstrated RF channel-select filter designed using the developed procedures and confirming theoretical predictions. Specifically, this dissertation introduces four methods that make possible the design and fabrication of RF channel-select filters. The first of these introduces a small-signal equivalent circuit for parallel-plate capacitive-gap transduced micromechanical resonators that employs negative capacitance to model the dependence of resonance frequency on electrical stiffness in a way that facilitates the analysis of micromechanical circuits loaded with arbitrary electrical impedances. The new circuit model not only correctly predicts the dependence of electrical stiffness on the impedances loading the input and output electrodes of parallel-plate capacitive-gap transduced micromechanical device, but does so in a visually intuitive way that identifies current drive as most appropriate for

  8. TRPV6 channels.

    Science.gov (United States)

    Fecher-Trost, Claudia; Weissgerber, Petra; Wissenbach, Ulrich

    2014-01-01

    TRPV6 (former synonyms ECAC2, CaT1, CaT-like) displays several specific features which makes it unique among the members of the mammalian Trp gene family (1) TRPV6 (and its closest relative, TRPV5) are the only highly Ca(2+)-selective channels of the entire TRP superfamily (Peng et al. 1999; Wissenbach et al. 2001; Voets et al. 2004). (2) Translation of Trpv6 initiates at a non-AUG codon, at ACG, located upstream of the annotated AUG, which is not used for initiation (Fecher-Trost et al. 2013). The ACG codon is nevertheless decoded by methionine. Not only a very rare event in eukaryotic biology, the full-length TRPV6 protein existing in vivo comprises an amino terminus extended by 40 amino acid residues compared to the annotated truncated TRPV6 protein which has been used in most studies on TRPV6 channel activity so far. (In the following numbering occurs according to this full-length protein, with the numbers of the so far annotated truncated protein in brackets). (3) Only in humans a coupled polymorphism of Trpv6 exists causing three amino acid exchanges and resulting in an ancestral Trpv6 haplotype and a so-called derived Trpv6 haplotype (Wissenbach et al. 2001). The ancestral allele encodes the amino acid residues C197(157), M418(378) and M721(681) and the derived alleles R197(157), V418(378) and T721(681). The ancestral haplotype is found in all species, the derived Trpv6 haplotype has only been identified in humans, and its frequency increases with the distance to the African continent. Apparently the Trpv6 gene has been a strong target for selection in humans, and its derived variant is one of the few examples showing consistently differences to the orthologues genes of other primates (Akey et al. 2004, 2006; Stajich and Hahn 2005; Hughes et al. 2008). (4) The Trpv6 gene expression is significantly upregulated in several human malignancies including the most common cancers, prostate and breast cancer (Wissenbach et al. 2001; Zhuang et al. 2002; Fixemer et al

  9. The Tie That Binds: Leadership and Liberal Arts Institutions' Civic Engagement Commitment in Rural Communities

    Science.gov (United States)

    Goodman, Hunter Phillips

    2014-01-01

    Community boundary spanners create ties that bind the campus and its surrounding region for reciprocal relationships. Using community boundary spanning literature as a conceptual framework, this study went beyond existing research on public and 4-year comprehensive universities to examine how university leadership at rural, private liberal arts…

  10. From the Cotton Fields to the Ties That Bind: Jim Pusack's Enduring Impact on Today's CALL Development

    Science.gov (United States)

    Jones, Linda C.

    2010-01-01

    From 1981 to today, the encouragement Jim Pusack and his colleague Sue Otto gave faculty to develop and/or implement CALL into the curriculum has been vital to our L2 teaching evolution. This article describes how their efforts evolved over the last two and a half decades and the ties that bind their efforts with today's CALL development.

  11. Transnational ties and the health of sub-Saharan African migrants: The moderating role of gender and family separation.

    Science.gov (United States)

    Afulani, Patience A; Torres, Jacqueline M; Sudhinaraset, May; Asunka, Joseph

    2016-11-01

    Recent scholarship has focused on the role that cross-border social and economic ties play in shaping health outcomes for migrant populations. Nevertheless, the extant empirical work on this topic has paid little attention to the health impacts of cross-border separation from close family members. In this paper we examine the association between cross-border ties-and cross-border separation-with the health of sub-Saharan African (SSA) migrant adults living in metropolitan France using data from the nationally representative "Trajectoire et Origines" survey (n = 1980 SSA migrants). In logistic regression analyses we find that remitting money and having a child abroad are each associated with poor health among women, but not men. The effect of remittances on health is also modified by the location of one's children: remittance sending is associated with poor health only for SSA-migrants separated from their children. These findings underscore the importance of examining both cross-border connection and cross-border separation in studies of immigrant health, and also underscore the heterogeneous relationships between cross-border ties and health for men and women. This is the first study to our knowledge that examines the relationship between cross-border ties and health for migrants in Europe, with a focus on SSA-migrants in France. These findings have important implications for the health of the growing immigrant and refugee populations in Europe and around the globe. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Disentangling School Leadership and Its Ties to Instructional Practices--An Empirical Comparison of Various Leadership Styles

    Science.gov (United States)

    Pietsch, Marcus; Tulowitzki, Pierre

    2017-01-01

    This paper investigates the direct and indirect ties between various leadership styles, namely, instructional, transformational, transactional, and laissez-faire leadership, and the instructional practices of teachers by applying a structural equation model. For this purpose, we analyzed survey data of n = 3,746 teachers from 126 schools collected…

  13. 49 CFR 1242.15 - Roadway, tunnels and subways, bridges and culverts, ties, rails, other track material, ballast...

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 9 2010-10-01 2010-10-01 false Roadway, tunnels and subways, bridges and culverts, ties, rails, other track material, ballast, track laying and surfacing, and road property damaged... RAILROADS 1 Operating Expenses-Way and Structures § 1242.15 Roadway, tunnels and subways, bridges and...

  14. Does Visual Impairment Affect Social Ties in Late Life? Findings of a Multicenter Prospective Cohort Study in Germany.

    Science.gov (United States)

    Hajek, A; Brettschneider, C; Lühmann, D; Eisele, M; Mamone, S; Wiese, B; Weyerer, S; Werle, J; Pentzek, M; Fuchs, A; Stein, J; Luck, T; Bickel, H; Weeg, D; Heser, K; Jessen, F; Maier, W; Scherer, M; Riedel-Heller, S G; König, H-H

    2017-01-01

    To investigate how visual impairment affects social ties in late life longitudinally. Population-based prospective cohort study. Individuals in old age were recruited via general practitioners' offices (at six study centers) in Germany. They were interviewed every 18 months. Individuals aged 75 years and above at baseline. Follow-up wave 2 (36 months after baseline, n=2,443) and wave 4 (72 months after baseline, n=1,618) were used for the analyses presented here. Social ties were assessed using the 14-item form of the questionnaire for social support (F-SozU K-14). Visual impairment was self-rated on a three level Likert scale (no impairment, mild visual impairment, or severe/profound visual impairment). Adjusting for sociodemographic factors, hearing impairment and comorbidity, fixed effects regressions revealed that the onset of mild visual impairment decreased the social support score, in particular the emotional support score. Additionally, the onset of mild hearing impairment decreased the social support score in men. Moreover, increasing age decreased the social support score in the total sample and in both sexes. Loss of spouse and increasing comorbidity did not affect the social support score. Our results highlight the importance of visual impairment for social ties in late life. Consequently, appropriate strategies in order to delay visual impairment might help to maintain social ties in old age.

  15. EFL Doctoral Students' Conceptions of Authorial Stance in Academic Knowledge Claims and the Tie to Epistemic Beliefs

    Science.gov (United States)

    Chang, Peichin; Tsai, Chin-Chung

    2014-01-01

    Taking an effective authorial stance in research argumentation has been designated as both vitally important and challenging. The study investigated English as a foreign language (EFL) doctoral students' conceptions of authorial stance, the role of domains in affecting their conceptions, and the ties of the conceptions to the participants'…

  16. A better way to teach knot tying: a randomized controlled trial comparing the kinesthetic and traditional methods.

    Science.gov (United States)

    Huang, Emily; Chern, Hueylan; O'Sullivan, Patricia; Cook, Brian; McDonald, Erik; Palmer, Barnard; Liu, Terrence; Kim, Edward

    2014-10-01

    Knot tying is a fundamental and crucial surgical skill. We developed a kinesthetic pedagogical approach that increases precision and economy of motion by explicitly teaching suture-handling maneuvers and studied its effects on novice performance. Seventy-four first-year medical students were randomized to learn knot tying via either the traditional or the novel "kinesthetic" method. After 1 week of independent practice, students were videotaped performing 4 tying tasks. Three raters scored deidentified videos using a validated visual analog scale. The groups were compared using analysis of covariance with practice knots as a covariate and visual analog scale score (range, 0 to 100) as the dependent variable. Partial eta-square was calculated to indicate effect size. Overall rater reliability was .92. The kinesthetic group scored significantly higher than the traditional group for individual tasks and overall, controlling for practice (all P kinesthetic overall mean was 64.15 (standard deviation = 16.72) vs traditional 46.31 (standard deviation = 16.20; P kinesthetic suture handling substantively improved performance on knot tying. We believe this effect can be extrapolated to more complex surgical skills. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Family Ties and Health Cross-Nationally: The Contextualizing Role of Familistic Culture and Public Pension Spending in Europe

    Science.gov (United States)

    2013-01-01

    Objectives. Although previous research theorizes that cross-national variation in the relationship between family ties and health is due to nation-level differences in culture and policy/economics, no study has examined this theorization empirically. Method. Using data from the Survey of Health, Ageing, and Retirement in Europe (SHARE) and the Organization for Economic Co-operation and Development (OECD), this study uses multilevel modeling to analyze individual-, nation-, and cross-level effects for 30,291 older adults in 14 nations. Results. Family ties to spouses/partners and parents are associated with better health, but ties to coresident children are associated with poorer health in certain contexts. Familistic culture and public pension spending have a weak but statistically significant moderating effect on the relationship between intergenerational family ties and health. Discussion. This article underscores the complexity of family and highlights the need for continued theorization and measurement at the nation level to promote older adults’ health in diverse contexts. PMID:24043356

  18. The rational weakness of strong ties : Failure of group solidarity in a highly cohesive group of rational agents

    NARCIS (Netherlands)

    Flache, Andreas

    2002-01-01

    Recent research (Flache, 1996; Flache and Macy, 1996) suggests a "weakness of strong ties." Cohesive social networks may undermine group solidarity, rather than sustain it. In the original analysis, simulations showed that adaptive actors learn cooperation in bilateral exchanges faster than

  19. The rational weakness of strong ties : Failure of group solidarity in a highly cohesive group of rational agents

    NARCIS (Netherlands)

    Flache, A; Yamamoto, H

    2006-01-01

    Recent research (Flache 1996; Flache and Macy 1996) suggests a "weakness of strong ties." Cohesive social networks may undermine group solidarity, rather than sustain it. In the original analysis, simulations showed that adaptive actors learn cooperation in bilateral exchanges faster than

  20. Transfer validity of laparoscopic knot-tying training on a VR simulator to a realistic environment : A randomized controlled trial

    NARCIS (Netherlands)

    Verdaasdonk, E.G.G.; Dankelman, J.; Lange, J.F.; Stassen, L.P.S.

    2007-01-01

    Background- Laparoscopic suturing is one of the most difficult tasks in endoscopic surgery, requiring extensive training. The aim of this study was to determine the transfer validity of knot-tying training on a virtual-reality (VR) simulator to a realistic laparoscopic environment. Methods- Twenty