WorldWideScience

Sample records for chilled sense structure

  1. The wind chilled the spectators, but the wine just chilled: Sense, structure, and sentence comprehension.

    Science.gov (United States)

    Hare, Mary; Elman, Jeffrey L; Tabaczynski, Tracy; McRae, Ken

    2009-03-31

    Anticipation plays a role in language comprehension. In this article, we explore the extent to which verb sense influences expectations about upcoming structure. We focus on change of state verbs like shatter, which have different senses that are expressed in either transitive or intransitive structures, depending on the sense that is used. In two experiments we influence the interpretation of verb sense by manipulating the thematic fit of the grammatical subject as cause or affected entity for the verb, and test whether readers' expectations for a transitive or intransitive structure change as a result. This sense-biasing context influenced reading times in the post-verbal regions. Reading times for transitive sentences were faster following good-cause than good theme subjects, but the opposite pattern was found for intransitive sentences. We conclude that readers use sense-contingent subcategorization preferences during on-line comprehension.

  2. Chills

    Science.gov (United States)

    Chills refers to feeling cold after being in a cold environment. The word can also refer to ... Chills (shivering) may occur at the beginning of an infection. They are most often associated with a ...

  3. The Relationships between Rheological Properties and Structural Changes of Chilled Abalone Meat

    Institute of Scientific and Technical Information of China (English)

    GAO Xin; ZHANG Zhaohui; TANG Zhixu; TASHIRO Yuri; OGAWA Hiroo

    2003-01-01

    The quantitative correlation between theological properties and structural characteristic values of chilled abalone meat was studied. Structural changes were observed, and these values were enumerated using image processing and analysis technique. Structural changes in the myofibrils and collagen fibrils were the greatest in chilling for 24 h. After chilling for 48 h, similar structures of vertical and cross sections were observed. For chilling from 0h to 72h, the instantaneous modulus E0 of the both section meat decreases gradually with time, but no significant differences were observed after chilling for 48 h.The relaxation time and viscosity of both sections attained the same values for the same chilling time, but increased gradually with increasing chilling time. Meanwhile, a negative correlation between the structural characteristic values (Dm, Am,Rvm), and rheological properties (E1,τi,η1) clearly exists. Some logarithmic expressions have been obtained for these negative correlations. These results suggest that the difference in rheological properties between the cross and vertical sections was mainly due to the structural changes of myofibrils and collagen fibrils, and rheological properties are influenced quantitatively by the structural characteristic values for chilling from 0 h to 72 h.

  4. Effect of Nb on Structure and Mechanical Properties of Chilled Cast Iron at Room and Elevated Temperatures

    Institute of Scientific and Technical Information of China (English)

    Qijie ZHAI; Li FU; Huaying ZHAI

    2004-01-01

    Effect of Nb on microstructure and mechanical properties of chilled cast iron at room and elevated temperatures is studied in this research. The results demonstrate that the cast structure and mechanical properties of chilled cast iron at room and elevated temperatures are improved with the addition of trace amount of Nb. However, if Nb was added too much, the cast structure and mechanical properties of chilled cast iron would deteriorate. The suitable content of Nb in chilled cast iron is about 0.05% (mass fraction). Except the dissolution in the matrix of cast iron the excessive Nb will form Nb-rich phases in three morphologies. Those are lumpy NbC, complicated strip-like phase and compound with pearlite structure.

  5. The chilling of carcasses.

    Science.gov (United States)

    Savell, J W; Mueller, S L; Baird, B E

    2005-07-01

    Biochemical processes and structural changes that occur in muscle during the first 24h postmortem play a great role in the ultimate quality and palatability of meat and are influenced by the chilling processes that carcasses are subjected to after slaughter. For beef and lamb, employing chilling parameters that minimize cold shortening is of greatest importance and can be best addressed by ensuring that muscle temperatures are not below 10°C before pH reaches 6.2. For pork, because of the impact of high muscle temperatures and low pH on the development of pale, soft, and exudative (PSE) pork, a more rapid chilling process is needed to reduce PSE with the recommended internal muscle temperature of 10°C at 12h and 2-4°C at 24h. Spray chilling, a system whereby chilled water is applied to carcasses during the early part of postmortem cooling, is used to control carcass shrinkage and to improve chilling rates through evaporative cooling. Delayed chilling can be used to reduce or prevent the negative effects of cold shortening; however, production constraints in high-volume facilities and food safety concerns make this method less useful in commercial settings. Electrical stimulation and alternative carcass suspension programs offer processors the opportunity to negate most or all of the effects of cold shortening while still using traditional chilling systems. Rapid or blast chilling can be an effective method to reduce the incidence of PSE in pork but extreme chilling systems may cause quality problems because of the differential between the cold temperatures on the outside of the carcass compared to the warm muscle temperatures within the carcass (i.e., muscles that are darker in color externally and lighter in color internally).

  6. Contrasting effect of dark-chilling on chloroplast structure and arrangement of chlorophyll-protein complexes in pea and tomato: plants with a different susceptibility to non-freezing temperature

    OpenAIRE

    Garstka, M.; Venema, J.H.; Rumak, I.; Gieczewska, K.; Rosiak, M.; Koziol-Lipinska, J.; Vredenberg, W J; Mostowska, A.

    2007-01-01

    The effect of dark-chilling and subsequent photoactivation on chloroplast structure and arrangements of chlorophyll-protein complexes in thylakoid membranes was studied in chilling-tolerant (CT) pea and in chilling-sensitive (CS) tomato. Dark-chilling did not influence chlorophyll content and Chl a/b ratio in thylakoids of both species. A decline of Chl a fluorescence intensity and an increase of the ratio of fluorescence intensities of PSI and PSII at 120 K was observed after dark-chilling i...

  7. Effect of Grain Refinement on Structure Evolution, “Floating” Grains, and Centerline Macrosegregation in Direct-Chill Cast AA2024 Alloy Billets

    NARCIS (Netherlands)

    Nadella, R.; Eskin, D.G.; Katgerman, L.

    2007-01-01

    Direct-chill (DC) cast billets 192 mm in diameter of an Al-Cu-Mg alloy were examined in detail with the aim to reveal the effects of grain refining (GR) and casting speed on structure, “floating” grains, and centerline macrosegregation. Experimental results show that grain size and dendrite arm spac

  8. Terahertz Plasmonic Structure With Enhanced Sensing Capabilities

    DEFF Research Database (Denmark)

    Yahiaoui, Riad; Strikwerda, Andrew C.; Jepsen, Peter Uhd

    2016-01-01

    We have designed, fabricated, and experimentally verified a highly sensitive plasmonic sensing device in the terahertz frequency range. For a proof of concept of the sensing phenomenon, we have chosen the so-called fishnet structure based on circular hole array insensitive to the polarization of ...

  9. How Structure Sense for Algebraic Expressions or Equations Is Related to Structure Sense for Abstract Algebra

    Science.gov (United States)

    Novotna, Jarmila; Hoch, Maureen

    2008-01-01

    Many students have difficulties with basic algebraic concepts at high school and at university. In this paper two levels of algebraic structure sense are defined: for high school algebra and for university algebra. We suggest that high school algebra structure sense components are sub-components of some university algebra structure sense…

  10. Chilled beam application guidebook

    CERN Document Server

    Butler, David; Gräslund, Jonas; Hogeling, Jaap; Lund Kristiansen, Erik; Reinikanen, Mika; Svensson, Gunnar

    2007-01-01

    Chilled beam systems are primarily used for cooling and ventilation in spaces, which appreciate good indoor environmental quality and individual space control. Active chilled beams are connected to the ventilation ductwork, high temperature cold water, and when desired, low temperature hot water system. Primary air supply induces room air to be recirculated through the heat exchanger of the chilled beam. In order to cool or heat the room either cold or warm water is cycled through the heat exchanger.

  11. Small-scale structure formation properties of chilled sterile neutrinos as dark matter

    CERN Document Server

    Petraki, Kalliopi

    2008-01-01

    We calculate the free-streaming length and the phase space density of dark-matter sterile neutrinos produced from decays of a gauge singlet in the Higgs sector. These quantities, which depend on the dark matter production mechanism, are relevant to the study of small-scale structure formation and may be used to constrain or rule out dark matter candidates.

  12. Small-scale structure formation properties of chilled sterile neutrinos as dark matter

    OpenAIRE

    Petraki, Kalliopi

    2008-01-01

    We calculate the free-streaming length and the phase space density of dark-matter sterile neutrinos produced from decays, at the electroweak scale, of a gauge singlet in the Higgs sector. These quantities, which depend on the dark-matter production mechanism, are relevant to the study of small-scale structure formation and may be used to constrain or rule out dark-matter candidates.

  13. Holographic sensing for control of flexible structures

    OpenAIRE

    Barsky, Michael Frederick

    1990-01-01

    A state feedback control system for flexible structures implemented using a holographic sensor and optical processor is presented. Real-time holography provides a mechanism for sensing the distributed shape of a broad class of one and two-dimensional flexible structures in a form that can be processed using fixed optics. The optical processing solves the spillover problem in the theory of the control of flexible structures. The optical processing also simplifies the computation allowing the s...

  14. Chilling Tendency and Chill of Cast Iron

    Institute of Scientific and Technical Information of China (English)

    E. Fra(s); M. Górny; W. Kapturkiewicz; H. López

    2008-01-01

    An analytical expression is presented for the susceptibility of liquid cast iron to solidify according tothe Fe-C-X metastable system (also known as the chilling tendency of cast iron, CT). The analysis incorpo-rates the nucleation and growth processes associated with the eutectic transformation. The CT is related tothe physicochemical state of the liquid, the eutectic cells in the flake graphite, and the number of nodules innodular cast iron. In particular, the CT can be related to the critical wall thickness, Scr, or the chill width, Wcr,in wedge shaped castings. Finally, this work serves as a guide for understanding the effect of technical fac-tors such as the melt chemistry, the spheroidizing and inoculation practice, and the holding time and tam-perature on the resultant CT and chill of the cast iron. Theoretical calculations of Scr and Wcr compare wellwith experimental data for flake graphite and nodular cast iron.

  15. Capacitive Structures for Gas and Biological Sensing

    KAUST Repository

    Sapsanis, Christos

    2015-04-01

    The semiconductor industry was benefited by the advances in technology in the last decades. This fact has an impact on the sensors field, where the simple transducer was evolved into smart miniaturized multi-functional microsystems. However, commercially available gas and biological sensors are mostly bulky, expensive, and power-hungry, which act as obstacles to mass use. The aim of this work is gas and biological sensing using capacitive structures. Capacitive sensors were selected due to its design simplicity, low fabrication cost, and no DC power consumption. In the first part, the dominant structure among interdigitated electrodes (IDEs), fractal curves (Peano and Hilbert) and Archimedean spiral was investigated from capacitance density perspective. The investigation consists of geometrical formula calculations, COMSOL Multiphysics simulations and cleanroom fabrication of the capacitors on a silicon substrate. Moreover, low-cost fabrication on flexible plastic PET substrate was conducted outside cleanroom with rapid prototyping using a maskless laser etching. The second part contains the humidity, Volatile Organic compounds (VOCs) and Ammonia sensing of polymers, Polyimide and Nafion, and metal-organic framework (MOF), Cu(bdc)2.xH2O using IDEs and tested in an automated gas setup for experiment control and data extraction. The last part includes the biological sensing of C - reactive protein (CRP) quantification, which is considered as a biomarker of being prone to cardiac diseases and Bovine serum albumin (BSA) protein quantification, which is used as a reference for quantifying unknown proteins.

  16. Spectral analysis based on compressive sensing in nanophotonic structures.

    Science.gov (United States)

    Wang, Zhu; Yu, Zongfu

    2014-10-20

    A method of spectral sensing based on compressive sensing is shown to have the potential to achieve high resolution in a compact device size. The random bases used in compressive sensing are created by the optical response of a set of different nanophotonic structures, such as photonic crystal slabs. The complex interferences in these nanostructures offer diverse spectral features suitable for compressive sensing.

  17. Occupant traffic estimation through structural vibration sensing

    Science.gov (United States)

    Pan, Shijia; Mirshekari, Mostafa; Zhang, Pei; Noh, Hae Young

    2016-04-01

    The number of people passing through different indoor areas is useful in various smart structure applications, including occupancy-based building energy/space management, marketing research, security, etc. Existing approaches to estimate occupant traffic include vision-, sound-, and radio-based (mobile) sensing methods, which have placement limitations (e.g., requirement of line-of-sight, quiet environment, carrying a device all the time). Such limitations make these direct sensing approaches difficult to deploy and maintain. An indirect approach using geophones to measure floor vibration induced by footsteps can be utilized. However, the main challenge lies in distinguishing multiple simultaneous walkers by developing features that can effectively represent the number of mixed signals and characterize the selected features under different traffic conditions. This paper presents a method to monitor multiple persons. Once the vibration signals are obtained, features are extracted to describe the overlapping vibration signals induced by multiple footsteps, which are used for occupancy traffic estimation. In particular, we focus on analysis of the efficiency and limitations of the four selected key features when used for estimating various traffic conditions. We characterize these features with signals collected from controlled impulse load tests as well as from multiple people walking through a real-world sensing area. In our experiments, the system achieves the mean estimation error of +/-0.2 people for different occupant traffic conditions (from one to four) using k-nearest neighbor classifier.

  18. Throughput Optimization via Cooperative Spectrum Sensing with Novel Frame Structure

    OpenAIRE

    Hang Hu; Hang Zhang; Hong Yu; Javad Jafarian

    2013-01-01

    In cognitive radio (CR) networks, cooperation can greatly improve the performance of spectrum sensing. In this paper, we propose a novel cooperative spectrum sensing (CSS) frame structure in which CR users conduct spectrum sensing and data transmission concurrently over two different parts of the primary user (PU) spectrum band. Energy detection sensing scheme is used to prove that there exists an optimal sensing bandwidth which yields the highest throughput for the CR network. Thus, we focus...

  19. Active structural waveguide for sensing application

    Science.gov (United States)

    Czajkowski, Karol; Kochanowicz, Marcin; Zmojda, Jacek; Miluski, Piotr; Dorosz, Dominik

    2014-05-01

    In the article a microstructural active optical fiber for sensing application was presented. Construction consists of three hexagonal rings and a core made of SiO2 - Al2O3 - Sb2O3 glass co-doped with 1Yb2O3/0.1Tm2O3 [mol%]. Developed optical fiber is characterized by upconversion luminescence (λp=980nm) at 480nm (Tm3+: 1G4→3H6) and 650 nm (Tm3+ : 1G4→3F4). Population of thulium levels was attained in result of the Yb 3+→Tm3+ upconversion energy transfer. Sensing application of elaborated active photonic structure was presented on the example of aqueous fluorescein solution. Fabricated microstructural optical fiber enables to measure of the fluorescein solutions with the concentration of (0.25 - 5.42)·10-4 [mol%]. Sensitivity of the elaborated measurement setup is 1.51·104 [1/mol%].

  20. Determining building interior structures using compressive sensing

    Science.gov (United States)

    Lagunas, Eva; Amin, Moeness G.; Ahmad, Fauzia; Nájar, Montse

    2013-04-01

    We consider imaging of the building interior structures using compressive sensing (CS) with applications to through-the-wall imaging and urban sensing. We consider a monostatic synthetic aperture radar imaging system employing stepped frequency waveform. The proposed approach exploits prior information of building construction practices to form an appropriate sparse representation of the building interior layout. We devise a dictionary of possible wall locations, which is consistent with the fact that interior walls are typically parallel or perpendicular to the front wall. The dictionary accounts for the dominant normal angle reflections from exterior and interior walls for the monostatic imaging system. CS is applied to a reduced set of observations to recover the true positions of the walls. Additional information about interior walls can be obtained using a dictionary of possible corner reflectors, which is the response of the junction of two walls. Supporting results based on simulation and laboratory experiments are provided. It is shown that the proposed sparsifying basis outperforms the conventional through-the-wall CS model, the wavelet sparsifying basis, and the block sparse model for building interior layout detection.

  1. Structured IR illumination for relative depth sensing in virtual interfaces

    Science.gov (United States)

    Kress, Bernard; Raulot, Victorien; Grossman, Michel

    2012-06-01

    Depth mapping or depth sensing has become a popular field, applied not only to automotive sensing for collision avoidance (radar) but also to gesture sensing for gaming and virtual interfaces (optical). Popular gesture sensing devices such as the Kinect from Microsoft's Xbox gaming device produce a full absolute depth map, which is in most cases not adapted to the task on hand (relative gesture sensing). We propose in this paper a new gesture sensing technique through structured IR illumination to provide a relative depth mapping rather than an absolute one, and this reducing the requirements on computing power and therefore enabling this technology for wearable computing such as see through display.

  2. STUDY OF CYLPEBS CHILLING

    Directory of Open Access Journals (Sweden)

    E. I. Marukovich

    2016-01-01

    Full Text Available Methods of increasing the shock resistance of cast-iron grinding bodies are researched. The models of heat transfer in the process of casting and shock-abrasive wear are presented. Tooling to produce experimental samples of milling bodies chilling(gravity die casting is manufactured, samples of cylpebs are produced.

  3. Satellite Remote Sensing Signatures of Impact Structures

    Science.gov (United States)

    Garvin, J. B.; Grieve, R. A. F.; Schnetzler, C. C.

    1995-09-01

    On Earth the impact record is preserved in the form of ~140 landforms [1], although current cratering flux estimates [2] suggest that hundreds of structures remain undiscovered on the terrestrial continents. A primary focus of our ongoing research efforts in this area has necessarily emphasized the geologically most recent impact events, especially those which formed in the last few million years. For example, we have comprehensively examined the orbital remote sensing characteristics of the Zhamanshin impact feature of Kazakhstan, a ~ 14 km diameter complex crater which apparently formed only ~870,000 years ago in a mixed sedimentary target [3]. In this case, we have been most fortunate to have available TM, SPOT Panchromatic (i.e, 10 m spatial resolution), SRL-1 and SRL-2 multiparameter SAR, and a ~ 90 m horizontal resolution DEM, along with excellent field data. The orbital multispectral data (TM) allowed us to discriminate the larger deposits of allogenic breccias at this youthful feature from erosionally emplaced surficial units, and a subtle signature of those areas covered with lag deposits of impact-related glass (zhamanshinites) was also identified [3,4]. As part of an ongoing collaboration with SRL scientists R. Greeley and D. Blumberg, we have also observed that L-band orbital SAR data clearly reveals the subtleties of the drainage networks that developed as a consequence of the cratering event, and which are apparently controlled by crater-related structures and deposit porosities [5]. When the geomorphically subtle Zhamanshin feature is compared against the Bosumtwi crater of Ghana, which apparently formed in crystalline shield rocks at around the same time (~ 1 million years ago), it appears that target rock properties have strongly influenced the level of preservation of these craters. Indeed, SPOT XS remote sensing data for Bosumtwi reveals a relatively pristine "lunar-like" complex crater with a raised rim, a quasi-polygonal outline, and a deep

  4. [Climatic risk zoning for banana and litchi's chilling injury in South China].

    Science.gov (United States)

    Li, Na; Huo, Zhi-guo; He, Nan; Xiao, Jing-jing; Wen, Quan-pei

    2010-05-01

    Based on the 1951-2006 climatic observation data from 224 meteorological stations in South China (Guangdong Province, Guangxi Autonomous Region, and Fujian Province) and the historical information about the chilling injury losses of banana and litchi, the accumulated harmful chilling for the processes with minimum daily temperature banana and litchi's chilling injury were drawn, and the spatial variation of climatic risk for banana and litchi's chilling injury was commented. The results indicated that in the study area, climate warming might lead to the decrease of cold resistance of banana and litchi, which could increase the disaster risk of chilling injury. The geographical distribution of climatic risk probability for banana and litchi's chilling injury showed a zonal pattern. According to the integrated climatic risk index, the banana and litchi's chilling injury region was divided into three risk types, i.e., high risk, moderate risk, and low risk, which provided an important basis for the adjustment of agricultural production structure.

  5. Recent advancement in optical fiber sensing for aerospace composite structures

    Science.gov (United States)

    Minakuchi, Shu; Takeda, Nobuo

    2013-12-01

    Optical fiber sensors have attracted considerable attention in health monitoring of aerospace composite structures. This paper briefly reviews our recent advancement mainly in Brillouin-based distributed sensing. Damage detection, life cycle monitoring and shape reconstruction systems applicable to large-scale composite structures are presented, and new technical concepts, "smart crack arrester" and "hierarchical sensing system", are described as well, highlighting the great potential of optical fiber sensors for the structural health monitoring (SHM) field.

  6. Study on spectral structure of quantum remote sensing

    Institute of Scientific and Technical Information of China (English)

    BI; Siwen; HAN; Jixia

    2006-01-01

    A study of the use of fine spectral structure in quantum remote sensing, including an expression, begins with a summary of present-day applications of spectrum remote sensing, which is followed by a theoretical discussion of the influence of electronic spin upon hydrogen-like atom energy levels and the calculation of spectral line in the absence of a circumstance field.

  7. Throughput Optimization via Cooperative Spectrum Sensing with Novel Frame Structure

    Directory of Open Access Journals (Sweden)

    Hang Hu

    2013-01-01

    Full Text Available In cognitive radio (CR networks, cooperation can greatly improve the performance of spectrum sensing. In this paper, we propose a novel cooperative spectrum sensing (CSS frame structure in which CR users conduct spectrum sensing and data transmission concurrently over two different parts of the primary user (PU spectrum band. Energy detection sensing scheme is used to prove that there exists an optimal sensing bandwidth which yields the highest throughput for the CR network. Thus, we focus on the optimal sensing settings of the proposed sensing scheme in order to maximize the throughput of the CR network under the conditions of sufficient protection to PUs and required bandwidth for potential CR user data transmission. Some algorithms are also derived to jointly optimize the sensing bandwidth and the final decision threshold. Our simulation results show that optimizing the sensing bandwidth and the final decision threshold together will further increase the throughput of the CR network as compared to that which only optimizes the sensing bandwidth or the final decision threshold.

  8. Welding Using Chilled-Inert-Gas Purging

    Science.gov (United States)

    Mcgee, William F.; Rybicki, Daniel J.

    1995-01-01

    Report describes study of fusion welding using chilled inert gas. Marked improvement shown in welding of aluminum using chilled helium gas. Chilling inert gas produces two additional benefits: 1) creation of ultradense inert atmosphere around welds; 2) chilled gas cools metal more quickly down to temperature at which metals not reactive.

  9. Young children's spatial structuring ability and emerging number sense

    NARCIS (Netherlands)

    van Nes, F.T.

    2009-01-01

    This thesis documents research into the role of young children’s spatial structuring ability in the development of number sense, particularly in terms of insight into numerical relations. We take Battista and Clements’ (1996, p. 503) definition to define the act of spatial structuring as “the mental

  10. Capacitance-based damage detection sensing for aerospace structural composites

    Science.gov (United States)

    Bahrami, P.; Yamamoto, N.; Chen, Y.; Manohara, H.

    2014-04-01

    Damage detection technology needs improvement for aerospace engineering application because detection within complex composite structures is difficult yet critical to avoid catastrophic failure. Damage detection is challenging in aerospace structures because not all the damage detection technology can cover the various defect types (delamination, fiber fracture, matrix crack etc.), or conditions (visibility, crack length size, etc.). These defect states are expected to become even more complex with future introduction of novel composites including nano-/microparticle reinforcement. Currently, non-destructive evaluation (NDE) methods with X-ray, ultrasound, or eddy current have good resolutions (analysis currently requires excessive wiring and complex signal analysis. Here, we present a capacitance sensor-based, structural defect detection technology with improved sensing capability. Thin dielectric polymer layer is integrated as part of the structure; the defect in the structure directly alters the sensing layer's capacitance, allowing full-coverage sensing capability independent of defect size, orientation or location. In this work, capacitance-based sensing capability was experimentally demonstrated with a 2D sensing layer consisting of a dielectric layer sandwiched by electrodes. These sensing layers were applied on substrate surfaces. Surface indentation damage (~1mm diameter) and its location were detected through measured capacitance changes: 1 to 250 % depending on the substrates. The damage detection sensors are light weight, and they can be conformably coated and can be part of the composite structure. Therefore it is suitable for aerospace structures such as cryogenic tanks and rocket fairings for example. The sensors can also be operating in space and harsh environment such as high temperature and vacuum.

  11. Passive and Active Sensing Technologies for Structural Health Monitoring

    Science.gov (United States)

    Do, Richard

    A combination of passive and active sensing technologies is proposed as a structural health monitoring solution for several applications. Passive sensing is differentiated from active sensing in that with the former, no energy is intentionally imparted into the structure under test; sensors are deployed in a pure detection mode for collecting data mined for structural health monitoring purposes. In this thesis, passive sensing using embedded fiber Bragg grating optical strain gages was used to detect varying degrees of impact damage using two different classes of features drawn from traditional spectral analysis and auto-regressive time series modeling. The two feature classes were compared in detail through receiver operating curve performance analysis. The passive detection problem was then augmented with an active sensing system using ultrasonic guided waves (UGWs). This thesis considered two main challenges associated with UGW SHM including in-situ wave propagation property determination and thermal corruption of data. Regarding determination of wave propagation properties, of which dispersion characteristics are the most important, a new dispersion curve extraction method called sparse wavenumber analysis (SWA) was experimentally validated. Also, because UGWs are extremely sensitive to ambient temperature changes on the structure, it significantly affects the wave propagation properties by causing large errors in the residual error in the processing of the UGWs from an array. This thesis presented a novel method that compensates for uniform temperature change by considering the magnitude and phase of the signal separately and applying a scalable transformation.

  12. Coordinated sensing and autonomous repair of pressure vessels and structures

    Science.gov (United States)

    Huston, Dryver R.; Hurley, David A.; Gollins, Kenneth; Gervais, Anthony

    2010-04-01

    Self-repairing structural systems can potentially improve performance ranges and lifetimes compared to those of conventional systems without self-healing capability. Self-healing materials have been used in automotive and aeronautical applications for over a century. The bulk of these systems operate by using the damage to directly initiate the repair response without any supervisory coordination. Integrating sensing and supervisory control technologies with self-healing may improve the safety and reliability of critical components and structures. This project used laboratory scale test beds to illustrate the benefit of an integrated sensing, control and self-healing system. A thermal healing polymer embedded with resistive heating wires acted as the sensing-healing material. Sensing duties were performed using an impedance, capacitance, and resistance testing device and a PC acted as the controller. As damage occurs to the polymer it is detected, located, and characterized. Based on the sensor signal, a decision is made as to whether to execute a repair and then to subsequently monitor the repair process to ensure completeness. The second demonstration was a self-sealing pressure vessel with integrated sensing and healing capability. These proof-of-concept prototypes can likely be expanded and improved with alternative sensor options, sensing-healing materials, and system architecture.

  13. New developments in sensing technology for structural health monitoring

    CERN Document Server

    Mukhopadhyay, Subhas Chandra

    2011-01-01

    The book has focussed on the different aspects of sensing technology, i.e. high reliability, adaptability, recalibration, information processing, data fusion, validation and integration of novel and high performance sensors specifically aims to use to inspect mechanical health of structure and similar applications. This book is dedicated to Sensing systems for Structural Health Monitoring offers to variety of users, namely, Master and PhD degree students, researchers, practitioners, especially Civil and Construction engineers. The book will provide an opportunity of a dedicated and a deep appr

  14. Young children's spatial structuring ability and emerging number sense

    OpenAIRE

    van Nes, F.T.

    2009-01-01

    This thesis documents research into the role of young children’s spatial structuring ability in the development of number sense, particularly in terms of insight into numerical relations. We take Battista and Clements’ (1996, p. 503) definition to define the act of spatial structuring as “the mental operation of constructing an organization or form for an object or set of objects”. Insight into numerical relations involves the structuring (e.g., (de)composing) of quantities (e.g., understandi...

  15. Sensing Structures Inspired by Blind Cave Fish

    Science.gov (United States)

    McConney, Michael E.; Chen, Nannan; Lu, David; Anderson, Kyle D.; Hu, Huan; Liu, Chang; Tsukruk, Vladimir V.

    2009-03-01

    Blind cave fish, with degenerated non-functioning eyes, have evolved to ``see'' their hydrodynamic environment by using the flow receptors of the lateral line system. The hair-cell receptors are encapsulated in a hydrogel-like material, called a cupula, which increases the sensitivity of the hair-cell receptors by coupling their motion to the surrounding flowing media. We characterized the viscoelastic properties and of blind cave fish cupulae by using colloidal-probe spectroscopy in fluid. A photo-patternable hydrogel with similar properties was developed to mimic the fish receptor coupling structure. Flow-based measurements indicated that the hydrogels enhance drag through increased surface area, but also inherent material properties. These bio-inspired structures endowed micro-fabricated flow sensors with sensitivities rivaling that of fish.

  16. Remote sensing of vegetation structure using computer vision

    Science.gov (United States)

    Dandois, Jonathan P.

    High-spatial resolution measurements of vegetation structure are needed for improving understanding of ecosystem carbon, water and nutrient dynamics, the response of ecosystems to a changing climate, and for biodiversity mapping and conservation, among many research areas. Our ability to make such measurements has been greatly enhanced by continuing developments in remote sensing technology---allowing researchers the ability to measure numerous forest traits at varying spatial and temporal scales and over large spatial extents with minimal to no field work, which is costly for large spatial areas or logistically difficult in some locations. Despite these advances, there remain several research challenges related to the methods by which three-dimensional (3D) and spectral datasets are joined (remote sensing fusion) and the availability and portability of systems for frequent data collections at small scale sampling locations. Recent advances in the areas of computer vision structure from motion (SFM) and consumer unmanned aerial systems (UAS) offer the potential to address these challenges by enabling repeatable measurements of vegetation structural and spectral traits at the scale of individual trees. However, the potential advances offered by computer vision remote sensing also present unique challenges and questions that need to be addressed before this approach can be used to improve understanding of forest ecosystems. For computer vision remote sensing to be a valuable tool for studying forests, bounding information about the characteristics of the data produced by the system will help researchers understand and interpret results in the context of the forest being studied and of other remote sensing techniques. This research advances understanding of how forest canopy and tree 3D structure and color are accurately measured by a relatively low-cost and portable computer vision personal remote sensing system: 'Ecosynth'. Recommendations are made for optimal

  17. Wireless sensing experiments for structural vibration monitoring of offshore platform

    Institute of Scientific and Technical Information of China (English)

    Yan YU; Jinping OU

    2008-01-01

    In order to validate the feasibility of applying wireless sensing technique to structural monitoring of offshore platform,the experiment of wireless sensor network on offshore platform is presented in this paper.First,wireless sensor network and its topology structure is put forward,and the design of sensor nodes,base station,communication protocol is discussed according to selfdeveloped wireless sensor network.Second,true offshore platform and its experimental model are introduced.Finally,wireless sensing experiment for offshore platform structure is completed and the analysis of the experimental result is given.The research shows that wireless sensor network applied to offshore platform can reflect the vibration of the structure;the sensor nodes are fixed and removed expediently,which saves the cost of signal line as well as installation time.

  18. Wireless Structural Sensing for Health Monitoring and Control Applications

    Science.gov (United States)

    Lynch, J. P.

    2003-12-01

    The economic and societal impact of civil structures under-performing during large earthquakes can be significant. While in recent years the structural engineering community has made great strides in advancing knowledge of structural behavior under extreme loads, a need still exists for the rapid assessment of structural performance during seismic events. Numerous options are commercially available to facility owners who wish to install a structural monitoring system within their structures. However, these structural monitoring systems are defined by their use of coaxial cables for the transfer of response measurements from sensors to centralized data servers. The installation and maintenance of cables within a civil structure often drive system costs high thereby preventing widespread industry adoption. In response to these limitations, the integration of information technologies such as wireless communications and microcontrollers have been explored for the creation of alternative structural monitoring systems defined by low installation costs and decentralized computational frameworks. In particular, a novel wireless structural monitoring system assembled from a dense network of inexpensive wireless sensing units has been designed and fabricated. The wireless sensing unit architecture consists of three functional components: a data acquisition interface for the collection of data from attached sensors, a computational core for data interrogation, and a wireless communication channel for the transfer of data to the sensor network. The use of wireless modems drastically reduces the efforts and costs of system installations rendering the technology attractive for widespread adoption in a broad class of civil structures. A second innovation of the system is the inclusion of computational power within each wireless sensing unit allowing for local execution of embedded engineering analyses. In particular, analyses for the detection of damage in structures (structural

  19. Smart Sensing Technologies for Structural Health Monitoring of Civil Engineering Structures

    OpenAIRE

    M. Sun; W.J. Staszewski; Swamy, R. N.

    2010-01-01

    Structural Health Monitoring (SHM) aims to develop automated systems for the continuous monitoring, inspection, and damage detection of structures with minimum labour involvement. The first step to set up a SHM system is to incorporate a level of structural sensing capability that is reliable and possesses long term stability. Smart sensing technologies including the applications of fibre optic sensors, piezoelectric sensors, magnetostrictive sensors and self-diagnosing fibre reinforced compo...

  20. Application of Multiscale Fiber Optical Sensing Network Based on Brillouin and Fiber Bragg Grating Sensing Techniques on Concrete Structures

    OpenAIRE

    Xuefeng Zhao; Jie Lu; Ruicong Han; Xianglong Kong; Yanhong Wang; Le Li

    2012-01-01

    The paper reports the application of the distributed optical fiber sensing technology and the FBG sensing technology in bridge strain monitoring; the overall changeable characteristics of the whole structure can be obtained through the distributed optical fiber sensing technology (BOTDA), meanwhile the accurate information of local important parts of the structure can be obtained through the optical fiber Bragg grating sensor (FBG), which can improve the accuracy of the monitoring. FBG sensor...

  1. Electrochemical structure-switching sensing using nanoplasmonic devices

    Energy Technology Data Exchange (ETDEWEB)

    Patskovsky, Sergiy; Dallaire, Anne-Marie; Blanchard-Dionne, Andre-Pierre; Meunier, Michel [Department of Engineering Physics, Laser Processing and Plasmonics Laboratory, Polytechnique, Montreal, Station Centre-ville, QC (Canada); Vallee-Belisle, Alexis [Laboratory of Biosensors and Nanomachines, Departement de Chimie, Universite de Montreal, QC (Canada)

    2015-12-15

    In this article, the implementation of electrochemical plasmonic nanostructures functionalized with DNA-based structure-switching sensors is presented. eNanoSPR devices with open and microfluidic measurement cells are developed on the base of nanohole arrays in 100 nm gold film and applied for combined microscopic and electrochemical surface plasmon (eSPR) visualization. eSPR voltammograms and spectroscopy are performed using planar three electrode schematic with plasmonic nanostructure operated as working electrode. Limit of detection of eNanoSPR devices for oligonucleotide hybridization is estimated in the low nanomolar and applications for structure-switching electro-plasmonic sensing in complex liquids are discussed. (copyright 2015 by WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  2. Virtual sensing of structural vibrations using dynamic substructuring

    Science.gov (United States)

    Kullaa, Jyrki

    2016-10-01

    Virtual sensing techniques use information available from a limited set of physical sensors together with the finite element model to calculate an estimate of the quantity of interest. In structural dynamics applications, analytical mode shapes from the finite element model are typically used as a basis to estimate the response at unmeasured locations by an expansion algorithm. An alternative is to model only the interesting part of the structure using substructuring techniques, in which the natural modes are replaced by component modes consisting of a selected number of fixed interface modes plus the interface constraint modes. They are mutually independent and compose a valid subspace for estimating the unmeasured response. If the number of interface degrees of freedom is large, interface reduction is applied. The main advantage of the proposed approach is that the modelling effort can be substantially decreased, because only part of the structure is modelled and the modelling uncertainties, non-linearities, or changes in the omitted structure can be ignored. The method is validated by numerical simulations of three different structures under unknown excitation. Different types and locations of virtual sensors are studied. Also, the effects of noise and model errors are investigated. The most accurate estimation is obtained if the virtual sensor is located away from the interface and close to a physical sensor.

  3. A new SMART sensing system for aerospace structures

    Science.gov (United States)

    Zhang, David C.; Yu, Pin; Beard, Shawn; Qing, Peter; Kumar, Amrita; Chang, Fu-Kuo

    2007-04-01

    It is essential to ensure the safety and reliability of in-service structures such as unmanned vehicles by detecting structural cracking, corrosion, delamination, material degradation and other types of damage in time. Utilization of an integrated sensor network system can enable automatic inspection of such damages ultimately. Using a built-in network of actuators and sensors, Acellent is providing tools for advanced structural diagnostics. Acellent's integrated structural health monitoring system consists of an actuator/sensor network, supporting signal generation and data acquisition hardware, and data processing, visualization and analysis software. This paper describes the various features of Acellent's latest SMART sensing system. The new system is USB-based and is ultra-portable using the state-of-the-art technology, while delivering many functions such as system self-diagnosis, sensor diagnosis, through-transmission mode and pulse-echo mode of operation and temperature measurement. Performance of the new system was evaluated for assessment of damage in composite structures.

  4. 3D Vegetation Structure Extraction from Lidar Remote Sensing

    Science.gov (United States)

    Ni-Meister, W.

    2006-05-01

    Vegetation structure data are critical not only for biomass estimation and global carbon cycle studies, but also for ecosystem disturbance, species habitat and ecosystem biodiversity studies. However those data are rarely available at the global scale. Multispectral passive remote sensing has shown little success on this direction. The upcoming lidar remote sensing technology shows a great potential to measure vegetation vertical structure data globally. In this study, we present and test a Bayesian Stochastic Inversion (BSI) approach to invert a full canopy Geometric Optical and Radiative Transfer (GORT) model to retrieve 3-D vegetation structure parameters from large footprint (15m-25m diameter) vegetation lidar data. BSI approach allows us to take into account lidar-directly derived structure parameters, such as tree height and the upper and lower bounds of crown height and their uncertainties as the prior knowledge in the inversion. It provides not only the optimal estimates of model parameters, but also their uncertainties. We first assess the accuracy of vegetation structure parameter retrievals from vegetation lidar data through a comprehensive GORT input parameter sensitivity analysis. We calculated the singular value decomposition (SVD) of Jacobian matrix, which contains the partial derivatives of the combined model with respect to all relevant model input parameters and. Our analysis shows that with the prior knowledge of tree height, crown depth and crown shape, lidar waveforms is most sensitive to the tree density, then to the tree size and the least to the foliage area volume density. It indicates that tree density can be retrieved with the most accuracy and then the tree size, the least is the foliage area volume density. We also test the simplified BSI approach through a synthetic experiment. The synthetic lidar waveforms were generated based the vegetation structure data obtained from the Boreal Ecosystem Atmosphere Study (BOREAS). With the exact

  5. Reduction of Chilling Injury and Ultrastructural Damage in Cherry Tomato Fruits After Hot Water Treatment

    Institute of Scientific and Technical Information of China (English)

    YANG Jing; FU Mao-run; ZHAO Yu-ying; MAO Lin-chun

    2009-01-01

    The effects of hot water treatment in alleviating chilling injury and reducing ultrastructural damage of mature-green cherry tomatoes (Lycopersicun esculentum cv. cerasiform Alef) were investigated. Mature-green cherry tomato fruits were treated in water at 40℃ or 45℃ for 5 rain or 15 rain, and then stored at 5℃ for 19 days followed by ripening at 20℃. Water treatment at 40℃ for 15 rain increased tolerance of cherry tomato fruits to chilling stress, indicating as low outbreak of skin lesion, high color a* value, and low electrolyte leakage. Treated fi'uits showed typical climacteric respiration and developed normal red color with chlorophyll degradation and lyeopene accumulation during ripening, while fruits without treatment failed to develop red color and suffered skin lesion. After 19 days of chilling, heated fruits showed the conversion of chloroplast to ehromoplast with the disappearance of thylakoids. Mitochondria and other cell organelles were not adversely affected in treated fruits. However, ultrastruetures in periearp cells in control fruits severely damaged with extensive disorganization of cytoplasm, swelled chloroplasts, distorted and unstacked thylakoids. Chloroplast was the first and most severely impacted organelle by chilling stress. Hot water treatment (40℃ for 15 min) before storage alleviated chilling injury in cherry tomato fruits. The results suggest that chilling injury is related with the damage of cell structure under chilling stress.

  6. Compressed Sensing Electron Tomography for Determining Biological Structure

    Science.gov (United States)

    Guay, Matthew D.; Czaja, Wojciech; Aronova, Maria A.; Leapman, Richard D.

    2016-06-01

    There has been growing interest in applying compressed sensing (CS) theory and practice to reconstruct 3D volumes at the nanoscale from electron tomography datasets of inorganic materials, based on known sparsity in the structure of interest. Here we explore the application of CS for visualizing the 3D structure of biological specimens from tomographic tilt series acquired in the scanning transmission electron microscope (STEM). CS-ET reconstructions match or outperform commonly used alternative methods in full and undersampled tomogram recovery, but with less significant performance gains than observed for the imaging of inorganic materials. We propose that this disparity stems from the increased structural complexity of biological systems, as supported by theoretical CS sampling considerations and numerical results in simulated phantom datasets. A detailed analysis of the efficacy of CS-ET for undersampled recovery is therefore complicated by the structure of the object being imaged. The numerical nonlinear decoding process of CS shares strong connections with popular regularized least-squares methods, and the use of such numerical recovery techniques for mitigating artifacts and denoising in reconstructions of fully sampled datasets remains advantageous. This article provides a link to the software that has been developed for CS-ET reconstruction of electron tomographic data sets.

  7. Robust signal recovery algorithm for structured perturbation compressive sensing

    Institute of Scientific and Technical Information of China (English)

    Youhua Wang; Jianqiu Zhang

    2016-01-01

    It is understood that the sparse signal recovery with a standard compressive sensing (CS) strategy requires the measurement matrix known as a priori. The measurement matrix is, however, often perturbed in a practical application. In order to handle such a case, an optimization problem by exploiting the sparsity characteristics of both the perturbations and signals is formulated. An algorithm named as the sparse perturbation signal recovery algorithm (SPSRA) is then pro-posed to solve the formulated optimization problem. The analytical results show that our SPSRA can simultaneously recover the signal and perturbation vectors by an alternative iteration way, while the convergence of the SPSRA is also analyticaly given and guaranteed. Moreover, the support patterns of the sparse signal and structured perturbation shown are the same and can be exploited to improve the estimation accuracy and reduce the computation complexity of the algorithm. The numerical simulation results verify the effectiveness of analytical ones.

  8. Compressive sensing based wireless sensor for structural health monitoring

    Science.gov (United States)

    Bao, Yuequan; Zou, Zilong; Li, Hui

    2014-03-01

    Data loss is a common problem for monitoring systems based on wireless sensors. Reliable communication protocols, which enhance communication reliability by repetitively transmitting unreceived packets, is one approach to tackle the problem of data loss. An alternative approach allows data loss to some extent and seeks to recover the lost data from an algorithmic point of view. Compressive sensing (CS) provides such a data loss recovery technique. This technique can be embedded into smart wireless sensors and effectively increases wireless communication reliability without retransmitting the data. The basic idea of CS-based approach is that, instead of transmitting the raw signal acquired by the sensor, a transformed signal that is generated by projecting the raw signal onto a random matrix, is transmitted. Some data loss may occur during the transmission of this transformed signal. However, according to the theory of CS, the raw signal can be effectively reconstructed from the received incomplete transformed signal given that the raw signal is compressible in some basis and the data loss ratio is low. This CS-based technique is implemented into the Imote2 smart sensor platform using the foundation of Illinois Structural Health Monitoring Project (ISHMP) Service Tool-suite. To overcome the constraints of limited onboard resources of wireless sensor nodes, a method called random demodulator (RD) is employed to provide memory and power efficient construction of the random sampling matrix. Adaptation of RD sampling matrix is made to accommodate data loss in wireless transmission and meet the objectives of the data recovery. The embedded program is tested in a series of sensing and communication experiments. Examples and parametric study are presented to demonstrate the applicability of the embedded program as well as to show the efficacy of CS-based data loss recovery for real wireless SHM systems.

  9. Aesthetic Chills: Knowledge-Acquisition, Meaning-Making, and Aesthetic Emotions.

    Science.gov (United States)

    Schoeller, Felix; Perlovsky, Leonid

    2016-01-01

    This article addresses the relation between aesthetic emotions, knowledge-acquisition, and meaning-making. We briefly review theoretical foundations and present experimental data related to aesthetic chills. These results suggest that aesthetic chills are inhibited by exposing the subject to an incoherent prime prior to the chill-eliciting stimulation and that a meaningful prime makes the aesthetic experience more pleasurable than a neutral or an incoherent one. Aesthetic chills induced by narrative structures seem to be related to the pinnacle of the story, to have a significant calming effect and subjects describe a strong empathy for the characters. We discuss the relation between meaning-making and aesthetic emotions at the psychological, physiological, narratological, and mathematical levels and propose a series of hypotheses to be tested in future research. PMID:27540366

  10. Aesthetic Chills: Knowledge-Acquisition, Meaning-Making, and Aesthetic Emotions.

    Science.gov (United States)

    Schoeller, Felix; Perlovsky, Leonid

    2016-01-01

    This article addresses the relation between aesthetic emotions, knowledge-acquisition, and meaning-making. We briefly review theoretical foundations and present experimental data related to aesthetic chills. These results suggest that aesthetic chills are inhibited by exposing the subject to an incoherent prime prior to the chill-eliciting stimulation and that a meaningful prime makes the aesthetic experience more pleasurable than a neutral or an incoherent one. Aesthetic chills induced by narrative structures seem to be related to the pinnacle of the story, to have a significant calming effect and subjects describe a strong empathy for the characters. We discuss the relation between meaning-making and aesthetic emotions at the psychological, physiological, narratological, and mathematical levels and propose a series of hypotheses to be tested in future research.

  11. Effect of local chilling on morphology of primary α (Al) in semi-solid A356 alloy

    Institute of Scientific and Technical Information of China (English)

    LIU Zheng; MAO Wei-min; ZHAO Zhen-duo

    2008-01-01

    The semi-solid slurry of A356 alloy was prepared by low superheat pouring and slightly electromagnetic stirring, in which a pure copper rod was used to produce local chilling. The effect of chilling by the rod on morphology and size of primary α (Al) in A356 was researched. The results indicate that the chilling by the rod remarkably affects the morphology and the size of primary α (Al). Primary α (Al) with particle-like shape is distributed uniformly in A356, and there is no transient area in structure morphology. Compared with the samples prepared without the local chilling, the nucleation rate, morphology and grain size of primary α (Al) in A356 prepared by low superheat pouring and slightly electromagnetic stirring with the rod are markedly improved. Under the condition of chilling, the pouring temperature can be suitably raised to obtain primary α (Al) with particle-like shape.

  12. Distributed Long-Gauge Optical Fiber Sensors Based Self-Sensing FRP Bar for Concrete Structure

    Science.gov (United States)

    Tang, Yongsheng; Wu, Zhishen

    2016-01-01

    Brillouin scattering-based distributed optical fiber (OF) sensing technique presents advantages for concrete structure monitoring. However, the existence of spatial resolution greatly decreases strain measurement accuracy especially around cracks. Meanwhile, the brittle feature of OF also hinders its further application. In this paper, the distributed OF sensor was firstly proposed as long-gauge sensor to improve strain measurement accuracy. Then, a new type of self-sensing fiber reinforced polymer (FRP) bar was developed by embedding the packaged long-gauge OF sensors into FRP bar, followed by experimental studies on strain sensing, temperature sensing and basic mechanical properties. The results confirmed the superior strain sensing properties, namely satisfied accuracy, repeatability and linearity, as well as excellent mechanical performance. At the same time, the temperature sensing property was not influenced by the long-gauge package, making temperature compensation easy. Furthermore, the bonding performance between self-sensing FRP bar and concrete was investigated to study its influence on the sensing. Lastly, the sensing performance was further verified with static experiments of concrete beam reinforced with the proposed self-sensing FRP bar. Therefore, the self-sensing FRP bar has potential applications for long-term structural health monitoring (SHM) as embedded sensors as well as reinforcing materials for concrete structures. PMID:26927110

  13. Distributed Long-Gauge Optical Fiber Sensors Based Self-Sensing FRP Bar for Concrete Structure.

    Science.gov (United States)

    Tang, Yongsheng; Wu, Zhishen

    2016-01-01

    Brillouin scattering-based distributed optical fiber (OF) sensing technique presents advantages for concrete structure monitoring. However, the existence of spatial resolution greatly decreases strain measurement accuracy especially around cracks. Meanwhile, the brittle feature of OF also hinders its further application. In this paper, the distributed OF sensor was firstly proposed as long-gauge sensor to improve strain measurement accuracy. Then, a new type of self-sensing fiber reinforced polymer (FRP) bar was developed by embedding the packaged long-gauge OF sensors into FRP bar, followed by experimental studies on strain sensing, temperature sensing and basic mechanical properties. The results confirmed the superior strain sensing properties, namely satisfied accuracy, repeatability and linearity, as well as excellent mechanical performance. At the same time, the temperature sensing property was not influenced by the long-gauge package, making temperature compensation easy. Furthermore, the bonding performance between self-sensing FRP bar and concrete was investigated to study its influence on the sensing. Lastly, the sensing performance was further verified with static experiments of concrete beam reinforced with the proposed self-sensing FRP bar. Therefore, the self-sensing FRP bar has potential applications for long-term structural health monitoring (SHM) as embedded sensors as well as reinforcing materials for concrete structures. PMID:26927110

  14. Distributed Long-Gauge Optical Fiber Sensors Based Self-Sensing FRP Bar for Concrete Structure.

    Science.gov (United States)

    Tang, Yongsheng; Wu, Zhishen

    2016-02-25

    Brillouin scattering-based distributed optical fiber (OF) sensing technique presents advantages for concrete structure monitoring. However, the existence of spatial resolution greatly decreases strain measurement accuracy especially around cracks. Meanwhile, the brittle feature of OF also hinders its further application. In this paper, the distributed OF sensor was firstly proposed as long-gauge sensor to improve strain measurement accuracy. Then, a new type of self-sensing fiber reinforced polymer (FRP) bar was developed by embedding the packaged long-gauge OF sensors into FRP bar, followed by experimental studies on strain sensing, temperature sensing and basic mechanical properties. The results confirmed the superior strain sensing properties, namely satisfied accuracy, repeatability and linearity, as well as excellent mechanical performance. At the same time, the temperature sensing property was not influenced by the long-gauge package, making temperature compensation easy. Furthermore, the bonding performance between self-sensing FRP bar and concrete was investigated to study its influence on the sensing. Lastly, the sensing performance was further verified with static experiments of concrete beam reinforced with the proposed self-sensing FRP bar. Therefore, the self-sensing FRP bar has potential applications for long-term structural health monitoring (SHM) as embedded sensors as well as reinforcing materials for concrete structures.

  15. Structure Assisted Compressed Sensing Reconstruction of Undersampled AFM Images

    DEFF Research Database (Denmark)

    Oxvig, Christian Schou; Arildsen, Thomas; Larsen, Torben

    2017-01-01

    The use of compressed sensing in atomic force microscopy (AFM) can potentially speed-up image acquisition, lower probe-specimen interaction, or enable super resolution imaging. The idea in compressed sensing for AFM is to spatially undersample the specimen, i.e. only acquire a small fraction...

  16. Methods and Prospects of Road and Linear Structure Automatic Extraction from Remote Sensing Images

    Institute of Scientific and Technical Information of China (English)

    LIU Zhengrong

    2003-01-01

    Automatic extraction of road and linear structure from remote sensing images is a very important problem. This paper analyses several existing methods of the automatic road and linear structure extraction by using some multi-spectral remote sensing images acquired from different spatial resolutions, districts and road characteristics. Their advantages and disadvantages have been generalized.

  17. Manipulation of monoubiquitin improves chilling tolerance in transgenic tobacco (Nicotiana tabacum).

    Science.gov (United States)

    Feng, Yanan; Zhang, Meng; Guo, Qifang; Wang, Guokun; Gong, Jiangfeng; Xu, Ying; Wang, Wei

    2014-02-01

    Ubiquitin (Ub) is a multifunctional protein that mainly functions to tag proteins for selective degradation by the 26S proteasome. We cloned an Ub gene TaUb2 from wheat (Triticum aestivum L.) previously. To study the function of TaUB2 in chilling stress, sense and antisense Ub transgenic tobacco plants (Nicotiana tabacum L.), as well as wild type (WT) and vector control β-glucuronidase (T-GUS) plants, were used. Under stress, leaf wilting in sense plants was significantly less than in controls, but more severe in antisense plants. Meanwhile, the net photosynthetic rate (Pn) and the maximal photochemical efficiency of PSII (Fv/Fm) in sense plants were greater than controls, but lower in antisense plants during chilling stress and recovery. Less wilting in sense plants resulted from improved water status, which may be related to the accumulation of proline and solute sugar. Furthermore, as indicated by electrolyte leakage, membrane damage under stress was less in sense plants and more severe in antisense plants than controls. Consistent with electrolyte leakage, the malondialdehyde (MDA) content was less in sense plants, but more in antisense plants compared to controls. Meanwhile, the less accumulation of reactive oxygen species (ROS) and the greater antioxidant enzyme activity in sense plants implied the improved antioxidant competence by the overexpression of monoubiquitin gene Ta-Ub2 from wheat. We suggest that overexpressing Ub is a useful strategy to promote chilling tolerance. The improvement of ROS scavenging may be an important mechanism underlying the role of Ub in promoting plants tolerant to chilling stress. PMID:24445300

  18. Quantitative Phosphoproteomics Reveals Signaling Mechanisms Associated with Rapid Cold Hardening in a Chill-Tolerant Fly.

    Science.gov (United States)

    Teets, Nicholas M; Denlinger, David L

    2016-08-01

    Rapid cold hardening (RCH) is a physiological adaptation in which brief chilling (minutes to hours) significantly enhances the cold tolerance of insects. RCH allows insects to cope with sudden cold snaps and diurnal variation in temperature, but the mechanistic basis of this rapid stress response is poorly understood. Here, we used phosphoproteomics to identify phosphorylation-mediated signaling events that are regulated by chilling that induces RCH. Phosphoproteomic changes were measured in both brain and fat bodies, two tissues that are essential for sensing cold and coordinating RCH at the organismal level. Tissues were chilled ex vivo, and changes in phosphoprotein abundance were measured using 2D electrophoresis coupled with Pro-Q diamond labeling of phosphoproteins followed by protein identification via LC-MS/MS. In both tissues, we observed an abundance of protein phosphorylation events in response to chilling. Some of the proteins regulated by RCH-inducing chilling include proteins involved in cytoskeletal reorganization, heat shock proteins, and proteins involved in the degradation of damaged cellular components via the proteasome and autophagosome. Our results suggest that phosphorylation-mediated signaling cascades are major drivers of RCH and enhance our mechanistic understanding of this complex phenotype. PMID:27362561

  19. Improving chill control in iron powder treated slightly hypereutectic grey cast irons

    Directory of Open Access Journals (Sweden)

    Iulian Riposan

    2011-05-01

    Full Text Available Recent studies revealed that in eutectic to slightly hypereutectic grey irons (CE = 4.3%-4.5% the presence of austenite dendrites provides an opportunity to improve the cast iron properties, as a high number of eutectic cells are “reinforced” by austenite dendrites. An iron powder addition proved to be important by promoting dendritic austenite in hypereutectic irons, but was accompanied by adverse effect on the characteristics of potential nuclei for graphite. The purpose of the present paper is to investigate the solidification pattern of these irons. Chill wedges with different cooling moduli (CM = 0.11 – 0.43 cm were poured in resin bonded sand and metal moulds. Relative clear / mottled / total chill measurement criteria were applied. Iron powder additions led to a higher chill tendency, while single inoculation showed the strongest graphitizing effect. The various double treatments show an intermediate position, but the inoculant added after iron powder appears to be the most effective in reducing base iron chill tendency, for all cooling moduli and chill evaluation parameters. This performance reflects the improved properties of (Mn,XS polygonal compounds as nucleation sites for graphite, especially in resin bonded sand mould castings. Both austenite and graphite nucleation benefit from a double addition of iron powder + inoculant, with positive effect on the final structure and chill tendency.

  20. Hazard identification and characterisation, and dose response assessment of spore forming pathogens in cooked chilled food containing vegetables

    NARCIS (Netherlands)

    Leusden FM van; MGB

    2001-01-01

    A hazard identification and characterisation, including a preliminary dose response assessment, of sporeforming pathogens in cooked chilled food containing vegetables was performed according to the structure and principles for a quantitative microbiological risk assessment as described by the Codex

  1. A mobile sensing system for structural health monitoring: design and validation

    International Nuclear Information System (INIS)

    This paper describes a new approach using mobile sensor networks for structural health monitoring. Compared with static sensors, mobile sensor networks offer flexible system architectures with adaptive spatial resolutions. The paper first describes the design of a mobile sensing node that is capable of maneuvering on structures built with ferromagnetic materials. The mobile sensing node can also attach/detach an accelerometer onto/from the structural surface. The performance of the prototype mobile sensor network has been validated through laboratory experiments. Two mobile sensing nodes are adopted for navigating on a steel portal frame and providing dense acceleration measurements. Transmissibility function analysis is conducted to identify structural damage using data collected by the mobile sensing nodes. This preliminary work is expected to spawn transformative changes in the use of mobile sensors for future structural health monitoring

  2. Overexpression of glycerol-3-phosphate acyltransferase gene improves chilling tolerance in tomato.

    Science.gov (United States)

    Sui, Na; Li, Meng; Zhao, Shi-Jie; Li, Feng; Liang, Hui; Meng, Qing-Wei

    2007-10-01

    A tomato (Lycopersicon esculentum Mill.) glycerol-3-phosphate acyltransferase gene (LeGPAT) was isolated. The deduced amino acid sequence revealed that LeGPAT contained four acyltransferase domains, showing high identities with GPAT in other plant species. A GFP fusion protein of LeGPAT was targeted to chloroplast in cowpea mesophyll protoplast. RNA gel blot showed that the mRNA accumulation of LeGPAT in the wild type (WT) was induced by chilling temperature. Higher expression levels were observed when tomato leaves were exposed to 4 degrees C for 4 h. RNA gel and western blot analysis confirmed that the sense gene LeGPAT was transferred into the tomato genome and overexpressed under the control of 35S-CaMV. Although tomato is classified as a chilling-sensitive plant, LeGPAT exhibited selectivity to 18:1 over 16:0. Overexpression of LeGPAT increased total activity of LeGPAT and cis-unsaturated fatty acids in PG in thylakoid membrane. Chilling treatment induced less ion leakage from the transgenic plants than from the WT. The photosynthetic rate and the maximal photochemical efficiency of PS II (Fv/Fm) in transgenic plants decreased more slowly during chilling stress and recovered faster than in WT under optimal conditions. The oxidizable P700 in both WT and transgenic plants decreased obviously at chilling temperature under low irradiance, but the oxidizable P700 recovered faster in transgenic plants than in the WT. These results indicate that overexpression of LeGPAT increased the levels of PG cis-unsaturated fatty acids in thylakoid membrane, which was beneficial for the recovery of chilling-induced PS I photoinhibition in tomato.

  3. Novel self-sensing carbon nanotube-based composites for rehabilitation of structural steel members

    Science.gov (United States)

    Ahmed, Shafique; Doshi, Sagar; Schumacher, Thomas; Thostenson, Erik T.; McConnell, Jennifer

    2016-02-01

    Fatigue and fracture are among the most critical forms of damage in metal structures. Fatigue damage can initiate from microscopic defects (e.g., surface scratches, voids in welds, and internal defects) and initiate a crack. Under cyclic loading, these cracks can grow and reach a critical level to trigger fracture of the member which leads to compromised structural integrity and, in some cases, catastrophic failure of the entire structure. In our research, we are investigating a solution using carbon nanotube-based sensing composites, which have the potential to simultaneously rehabilitate and monitor fatigue-cracked structural members. These composites consist of a fiber-reinforced polymer (FRP) layer and a carbon nanotube-based sensing layer, which are integrated to form a novel structural self-sensing material. The sensing layer is composed of a non-woven aramid fabric that is coated with carbon nanotubes (CNT) to form an electrically conductive network that is extremely sensitive to detecting deformation as well as damage accumulation via changes in the resistance of the CNT network. In this paper, we introduce the sensing concept, describe the manufacturing of a model sensing prototype, and discuss a set of small-scale laboratory experiments to examine the load-carrying capacity and damage sensing response.

  4. Conventional food preparation, cook and chill and sous-vide as optional methods for institutional kitchens. Perinteinen ruoanvalmistus, cook and chill ja sous-vide toimintavaihtoehdot suurkeittioessae

    Energy Technology Data Exchange (ETDEWEB)

    Paeivaerinta, T., Reisbacka, A., Salminen, M.

    1993-01-01

    The purpose of the study was to clarify the situation concerning the energy consumption, economics and the appropriateness of the three options when applied in institutional households. The options included in the study were conventional (preparation-cooking-serving), cook and chill and sous-vide (vacuum cooking-chilling). A further aim was to compare industrially produced products to self-made products. Each option was studied in connection with several devices embodying latest technology. The overall price for a portion was found to be cheapest when using the conventional preparation method. The cook and chill method was only slightly more expensive. The result of this study also support the understanding that when appropriately planned, cook and chill and sous-vide food preparation options make possible the rationalisation of kitchen work. The appropriateness of different food preparation methods depends on the versatility of the functions and programmes built into cooking devices. A combination oven is appropriate and conserves energy when cooking or heating up large quantities. Significant waste of water (126-146 1/h) is possible because of the structural solutions and modes of use of such an oven. A microwave oven saves energy when used to heat up ready-made portions. The amount of energy consumed by an air-cooled chilling cabinet in the cooling of food makes it more economical to use than a water-cooled model. The amount of electricity consumed by a refrigerator or an equivalent cold storage is 5-14 times less than that consumed by chilling devices

  5. Tappet Chill Depth Measuring by Magnetic Permeability and Inductance Displacement Meter

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    It is possible to measure different position along the axle direction of tappet. According to the maximum output of signal, the boundary of white iron structure and mottled iron structure can be deduced, and at the same time, it is possible to use inductance displacement meter to show the chill depth which is the distance from the boundary to the end.

  6. Method for Real-Time Structure Shape-Sensing

    Science.gov (United States)

    Ko, William L. (Inventor); Richards, William Lance (Inventor)

    2009-01-01

    The invention is a method for obtaining the displacement of a flexible structure by using strain measurements obtained by stain sensor,. By obtaining the displacement of structures in this manner, one may construct the deformed shape of the structure and display said deformed shape in real-time, enabling active control of the structure shape if desired.

  7. Nanofluidic structures for coupled sensing and remediation of toxins

    Science.gov (United States)

    Shaw, K.; Contento, N. M.; Xu, Wei; Bohn, P. W.

    2014-05-01

    One foundational motivation for chemical sensing is that knowledge of the presence and level of a chemical agent informs decisions about treatment of the agent, for example by sequestration, separation or chemical conversion to a less harmful substance. Commonly the sensing and treatment steps are separate. However, the disjoint detection/treatment approach is neither optimal, nor required. Thus, we are investigating how nanostructured architectures can be constructed so that molecular transport (analyte/reagent delivery), chemical sensing (optical or electrochemical) and subsequent treatment can all be coupled in the same physical space during the same translocation event. Chemical sensors that are uniquely well-poised for integration into 3-D micro-/nanofluidic architectures include those based on plasmonics and impedance. Following detection, treatment can be substantially enhanced if mass transport limitations can be overcome. In this context, in situ generation of reactive species within confined geometries, such as nanopores or nanochannels, is of significant interest, because of its potential utility in overcoming mass transport limitations in chemical reactivity. Solvent electrolysis in electrochemically coupled nanochannels supporting electrokinetic flow for the generation of reactive species, can produce arbitrarily tunable quantities of reagents, such as O2 or H2, in situ in close proximity to the site of a hydrogenation catalyst, for example. Semi-quantitative estimates of the local H2 concentration are obtained by comparing the spatiotemporal fluorescence behavior and current measurements with finite element simulations accounting for electrolysis and subsequent convection and diffusion within the confined geometry. H2 saturation can easily be achieved at modest overpotentials.

  8. Methods for Enhancing Geological Structures in Spectral Spatial Difference-Based on Remote-Sensing Image

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    @@In this paper, some image processing methods such as directional template (mask) matching enhancement, pseudocolor or false color enhancement, K-L transform enhancement are used to enhance a geological structure, one of important ore-controlling factors, shown in the remote-sensing images.This geological structure is regarded as image anomaly in the remote-sensing image, since considerable differences, based on the spatial spectral distribution pattern, in gray values (spectral), color tones and texture, are always present between the geological structure and background. Therefore,the enhancement of the geological structure in the remotesensing image is that of the spectral spatial difference.

  9. Application of nano-structured conducting polymers to humidity sensing

    Science.gov (United States)

    Park, Pilyeon

    moisture levels because even low humidity levels saturate the sample surface within a few minutes. Because of this, it was not perfect to distinguish the effects of etching the PEDOT film for humidity detection and difficult to apply nano-columned PEDOT films as a humidity sensors under continuously changing humidity conditions. However, nano-columned PEDOT films showed excellent performance in simulated breath tests, i.e., an area where the medical needs sensors for pulmonary monitoring. Since the polymers are sensitive to heat, it was important to characterize the influence of temperature on the sensor performance. PANI nanowires and nano-columned PEDOT sensors were tested in the environmental chamber developed in this work as a function of temperature with the humidity fixed, and only the temperature was varied. The PANI nanowires showed very fast degradation at temperatures above room temperature, while the nano-columned PEDOT film performed up to 50 °C. The influence of other gases was also tested for the potential of gas sensing, selectivity, and chemical stability. In order to exclude the moisture effect during the measurement, the samples were characterized under the lowest humidity condition, RH 14% preserved in the system. Under these conditions the PANI nanowires responded to the gases (hydrogen and carbon monoxide were used), but the moisture inside the PANI nanowire was forced to influence the gas detection. Therefore, samples were dried overnight under a nitrogen environment and tested again. With this careful control of the moisture present, it was found that PANI nanowires respond to both hydrogen and carbon monoxide gases, however, there is no selectivity between gases. Nano-columned PEDOT films were also tested under the same experimental moisture-controlling conditions. It was shown that there was little response to other gases. Any response that may have been presented was buried in the electrical noise. Finally, both samples were tested for long

  10. Wireless, Low Mass, High Sensitivity Sensing Sheet for Structural Sensing and Long Term Analysis Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA needs sensor systems to inspect space structures with minimum human interaction. These systems must be highly integrated and self-sufficient, low mass, simple...

  11. Bio-inspired artificial muscle structure for integrated sensing and actuation

    Science.gov (United States)

    Ye, Zhihang; Faisal, Md. Shahnewaz Sabit; Asmatulu, Ramazan; Chen, Zheng

    2015-04-01

    In this paper, a novel artificial muscle/tendon structure is developed for achieving bio-inspired actuation and self-sensing. The hybrid structure consists of a dielectric elastomer (DE) material connected with carbon fibers, which incorporates the built-in sensing and actuation capability of DE and mechanical, electrical interfacing capability of carbon fibers. DEs are light weight artificial muscles that can generate compliant actuation with low power consumption. Carbon fibers act as artificial tendon due to their high electro-conductivity and mechanical strength. PDMS material is used to electrically and mechanically connect the carbon fibers with the DE material. A strip actuator was fabricated to verify the structure design and characterize its actuation and sensing capabilities. A 3M VHB 4905 tape was used as the DE material. To make compliant electrodes on the VHB tape, carbon black was sprayed on the surface of VHB tape. To join the carbon fibers to the VHB tape, PDMS was used as bonding material. Experiments have been conducted to characterize the actuation and sensing capabilities. The actuation tests have shown that the energy efficiency of artificial muscle can reach up to 0.7% and the strain can reach up to 1%. The sensing tests have verified that the structure is capable of self-sensing through the electrical impedance measurement.

  12. Protection of ultrastructure in chilling-stressed banana leaves by salicylic acid

    Institute of Scientific and Technical Information of China (English)

    KANG Guo-zhang; WANG Zheng-xun; XIA Kuai-fei; SUN Gu-chou

    2007-01-01

    Objective: Chilling tolerance of salicylic acid (SA) in banana seedlings (Musa acuminata cv., Williams 8818) was investigated by changes in ultrastructure in this study. Methods: Light and electron microscope observation. Results: Pretreatment with 0.5 mmol/L SA under normal growth conditions (30/22 ℃) by foliar spray and root irrigation resulted in many changes in ultrastructure of banana cells, such as cells separation from palisade parenchymas, the appearance of crevices in cell walls, the swelling of grana and stromal thylakoids, and a reduction in the number of starch granules. These results implied that SA treatment at 30/22 ℃ could be a type of stress. During 3 d of exposure to 7 ℃ chilling stress under low light, however, cell ultrastructure of SA-pretreated banana seedlings showed less deterioration than those of control seedlings (distilled water-pretreated). Conclusion:SA could provide some protection for cell structure of chilling-stressed banana seedling.

  13. Guns on Campus: A Chilling Effect

    Science.gov (United States)

    Mash, Kenneth M.

    2013-01-01

    The author of this article observes that, while much has been written on the overall topic of safety with regard to allowing guns on college campuses, little has been said about how allowing the possession of deadly weapons can create a "chilling effect" on academic discussions. This article considers how some universities have…

  14. STUDY ON MORPHOLOGY OF CHROMIUM IN CHILLED Cu-0.14%-2.0%Cr ALLOYS

    Institute of Scientific and Technical Information of China (English)

    H.W.Yang; Z.K.Fan

    2004-01-01

    The morphology of chromium in chilled Cu-Cr alloys with 0.14%-2.0% Cr has been studied. The results showed that eutectic Cr phase takes a fibrous shape, and pre-eutectic Cr is dendritic in the studied chilled Cu-Cr alloy. During solute treatment of the eutectic and super-eutectic Cu-Cr alloys, only part of chromium particles dissolved in copper phase,some fiber and dendritic chromium still remained. Forging before solute treatment can reduce the size of primary Cr particles, which benefits the aging structure.

  15. Distributed Long-Gauge Optical Fiber Sensors Based Self-Sensing FRP Bar for Concrete Structure

    OpenAIRE

    Tang, Yongsheng; Wu, Zhishen

    2016-01-01

    Brillouin scattering-based distributed optical fiber (OF) sensing technique presents advantages for concrete structure monitoring. However, the existence of spatial resolution greatly decreases strain measurement accuracy especially around cracks. Meanwhile, the brittle feature of OF also hinders its further application. In this paper, the distributed OF sensor was firstly proposed as long-gauge sensor to improve strain measurement accuracy. Then, a new type of self-sensing fiber reinforced p...

  16. Methanol-Sensing Property Improvement of Meso structured Zinc Oxide Prepared by the Nano casting Strategy

    International Nuclear Information System (INIS)

    The specific structure and morphology often play a critical role in governing the excellent intrinsic properties of the compound semiconductor. Herein, meso structured ZnO with excellent methanol-sensing properties was prepared by a structure replication procedure through the incipient wetness technique. The investigation on the crystal structure and morphology of the resultant material shows that the product consists of hexagonally arranged meso pores and crystalline walls, and its structure is an ideal replication of CMK-3 template. Consequently, meso structured ZnO was fabricated as a gas sensor for methanol. The excellent methanol-sensing performance was achieved at a relatively low operating temperature of 120°C. In comparison with the non porous ZnO prepared through conventional coprecipitation approach, meso structured ZnO material shows the higher sensitivity and stability. Furthermore, it shows the discrimination between methanol and ethanol sensitivity, which makes it a good candidate in fabricating selective methanol sensor in practice

  17. Toward the Soundness of Sense Structure Definitions in Thesaurus-Dictionaries. Parsing Problems and Solutions

    Directory of Open Access Journals (Sweden)

    Neculai Curteanu

    2012-10-01

    Full Text Available In this paper we point out some difficult problems of thesaurus-dictionary entry parsing, relying on the parsing technology of SCD (Segmentation-Cohesion-Dependency configurations, successfully applied on six largest thesauri -- Romanian (2, French, German (2, and Russian. \\textbf{Challenging Problems:} \\textbf{(a}~Intricate and~/~or recursive structures of the lexicographic segments met in the entries of certain thesauri; \\textbf{(b}~Cyclicity (recursive calls of some sense marker classes on marker sequences; \\textbf{(c}~Establishing the hypergraph-driven dependencies between all the atomic and non-atomic sense definitions. Classical approach to solve these parsing problems is hard mainly because of depth-first search of sense definitions and markers, the substantial complexity of entries, and the sense tree dynamic construction embodied within these parsers. \\textbf{SCD-based Parsing Solutions:} \\textbf{(a}~The SCD parsing method is a procedural tool, completely formal grammar-free, handling the recursive structure of the lexicographic segments by procedural non-recursive calls performed on the SCD parsing configurations of the entry structure. \\textbf{(b}~For dealing with cyclicity (recursive calls between secondary sense markers and the sense enumeration markers, we proposed the Enumeration Closing Condition, sometimes coupled with New{\\_}Paragraphs typographic markers transformed into numeral sense enumeration. \\textbf{(c}~These problems, their lexicographic modeling and parsing solutions are addressed to both dictionary parser programmers to experience the SCD-based parsing method, as well as to lexicographers and thesauri designers for tailoring balanced lexical-semantics granularities and sounder sense tree definitions of the dictionary entries.

  18. A mobile-agent-based wireless sensing network for structural monitoring applications

    International Nuclear Information System (INIS)

    A new wireless sensing network paradigm is presented for structural monitoring applications. In this approach, both power and data interrogation commands are conveyed via a mobile agent that is sent to sensor nodes to perform intended interrogations, which can alleviate several limitations of the traditional sensing networks. Furthermore, the mobile agent provides computational power to make near real-time assessments on the structural conditions. This paper will discuss such prototype systems, which are used to interrogate impedance-based sensors for structural health monitoring applications. Our wireless sensor node is specifically designed to accept various energy sources, including wireless energy transmission, and to be wirelessly triggered on an as-needed basis by the mobile agent or other sensor nodes. The capabilities of this proposed sensing network paradigm are demonstrated in the laboratory and the field

  19. Structural Health Monitoring of Civil Infrastructure Using Optical Fiber Sensing Technology: A Comprehensive Review

    Directory of Open Access Journals (Sweden)

    X. W. Ye

    2014-01-01

    Full Text Available In the last two decades, a significant number of innovative sensing systems based on optical fiber sensors have been exploited in the engineering community due to their inherent distinctive advantages such as small size, light weight, immunity to electromagnetic interference (EMI and corrosion, and embedding capability. A lot of optical fiber sensor-based monitoring systems have been developed for continuous measurement and real-time assessment of diversified engineering structures such as bridges, buildings, tunnels, pipelines, wind turbines, railway infrastructure, and geotechnical structures. The purpose of this review article is devoted to presenting a summary of the basic principles of various optical fiber sensors, innovation in sensing and computational methodologies, development of novel optical fiber sensors, and the practical application status of the optical fiber sensing technology in structural health monitoring (SHM of civil infrastructure.

  20. A mobile-agent based wireless sensing network for structural monitoring applications

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, Stuart G [Los Alamos National Laboratory; Farinholt, Kevin M [Los Alamos National Laboratory; Figueiredo, Eloi [Los Alamos National Laboratory; Park, Gyuhae [Los Alamos National Laboratory; Farrar, Charles R [Los Alamos National Laboratory; Flynn, Eric B [UCSD; Mascarenas, David L [UCSD; Todd, Michael D [UCSD

    2008-01-01

    A new wireless sensing network paradigm is presented for structural monitoring applications. In this approach, both power and data interrogation commands are conveyed via a mobile agent that is sent to sensor nodes to perform intended interrogations, which can alleviate several limitations of the traditional sensing networks. Furthermore, the mobile agent provides computational power to make near real-time assessments on the structural conditions. This paper will discuss such prototype systems, which are used to interrogate impedance-based sensors for structural health monitoring applications. Our wireless sensor node is specifically designed to accept various energy sources, including wireless energy transmission, and to be wirelessly triggered on an as-needed basis by the mobile agent or other sensor nodes. The capabilities of this proposed sensing network paradigm are demonstrated in the laboratory and the field.

  1. Optical fiber based sensing system design for the health monitoring of multi-layered pavement structure

    Science.gov (United States)

    Liu, Wanqiu; Wang, Huaping; Zhou, Zhi; Li, Shiyu; Ni, Yuanbao; Wang, Geng

    2011-11-01

    This paper introduces an optical fiber based sensing system design for multi-layered pavement structural health monitoring. The co-line and integration design of FBG (Fiber Bragg Gating) sensors and BOTDR (Brillouin Optical Time Domain Reflectometry) sensors will ensure the large scale damage monitoring and local high accurate strain measurement. The function of pavement structure multi-scale shape measurement will provide real time subgrade settlement and rutting information. The sensor packaging methodology and strain transfer problem of the system will also be discussed in this paper. Primary lab tests prove the potential and feasibility of the practical application of the sensing system.

  2. Higher Chilling-Tolerance of Grafted-Cucumber Seedling Leaves upon Exposure to Chilling Stress

    Institute of Scientific and Technical Information of China (English)

    LI Jian-yong; TIAN Hai-xia; LI Xin-guo; MENG Jing-jing; HE Qi-wei

    2008-01-01

    The roots of figleaf gourd (Cucurbita ficifolia, as rootstock) could improve the resistance of cucumber plants (Cucumis sativus L. cv. Jinyan 4, as scion) to low temperature. In this experiment, the root activity and photosynthetic activity of photosystems in the own-rooted and grafted-cucumber plants were studied at chilling temperature (4℃) under low irradiance (100 μmol m-2 s-1 PFD). Compared with dark adaptation seedlings, the chlorophyll a fluorescence transient curve and the oxidizable P700 (P700+) of both the own-rooted and grafted seedlings decreased, and PS2 and PSl of the own-rooted seedling leaves were more inhibited than that of grafted ones at the end of chilling stress. The reduced triphenyltetrazolium chloride (TTC), which was used to reflect the root activity, kept stable in grafted seedling roots at the end of chilling stress, while it decreased noticeably in the own-rooted seedling roots. These results implied that the root system activity of the grafted seedling roots was higher than that of the own-rooted ones. Superoxide dismutase (SOD) activity was higher in both the grafted seedling roots and leaves than that in own-rooted seedlings at both room temperature and chilling temperature. Upon exposure to chilling stress, the malondialdehyde (MDA) content, which reflects the degree of lipid peroxidation, increased markedly in the own-rooted seedling roots and leaves and kept stable in the grafted-cucumber seedlings.

  3. Integrating optical glucose sensing into a planar waveguide sensor structure

    Science.gov (United States)

    Dutta, Aradhana; Deka, Bidyut; Sahu, Partha P.

    2013-06-01

    A device for glucose monitoring in people with diabetes is a clinical and research priority in the recent years for its accurate self management. An extensive theoretical design and development of an optical sensor is carried out incorporating planar waveguide structure in an endeavor to measure slight changes of glucose concentration. The sensor is simple and highly sensitive and has the potential to be used for online monitoring of blood glucose levels for the diabetic patients in the near future.

  4. Directional distribution of chilling winds in Estonia

    Science.gov (United States)

    Saue, Triin

    2016-08-01

    Wind chill equivalent temperature (WCET) is used to define thermal discomfort in winter months. Directional distributions of winds, which are associated with uncomfortable weather, were composed of three climatologically different Estonian locations: Vilsandi, Kuusiku, and Jõhvi. Cases with wind chill equivalent temperature <-10 °C, which could be classified as "uncomfortable or worse," were investigated. Additional thresholds were used to measure weather risk. The 25th percentile of daily minimum WCET was tested to measure classical prevalent wind directions in Estonia: W, SW, and NW bring warm air in winter from the North Atlantic, while winds from the East-European plain (NE, E, and SE) are associated with cold air. The eastern prevalence was stronger when a lower threshold was used. A directional approach may find several applications, such as building, agricultural, landscape, or settlement planning.

  5. Switchable photooxygenation catalysts that sense higher-order amyloid structures

    Science.gov (United States)

    Taniguchi, Atsuhiko; Shimizu, Yusuke; Oisaki, Kounosuke; Sohma, Youhei; Kanai, Motomu

    2016-10-01

    Proteins can misfold into amyloid structures that are associated with diseases; however, the same proteins often have important biological roles. To degrade selectively the amyloid form without affecting the fraction of functional protein is, therefore, an attractive goal. Here we report target-state-dependent photooxygenation catalysts that are active only when bound to the cross-β-sheet structure that is characteristic of pathogenic aggregated amyloid proteins. We show these catalysts can selectively oxygenate the amyloid form of amyloid β-protein (Aβ) 1-42 in the presence of non-amyloid off-target substrates. Furthermore, photooxygenation with a catalyst that bears an Aβ-binding peptide attenuated the Aβ pathogenicity in the presence of cells. We also show that selective photooxygenation is generally applicable to other amyloidogenic proteins (amylin, insulin, β2-microglobulin, transthyretin and α-synuclein) and does not affect the physiologically functional non-aggregate states of these proteins. This is the first report of an artificial catalyst that can be selectively and reversibly turned on and off depending on the structure and aggregation state of the substrate protein.

  6. The Structural Basis for the Sensing and Binding of Cyclic di-GMP by STING

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Under a research project funded by NSFC, Prof. Su Xiaodong and his team of the National Laboratory of Protein Engineering and Plant Genetic Engineering, BIOPIC, the School of Life Sciences of Peking Uni- versity, obtained remarkable achievement and published recently a paper entitled "The Structural Basis for the Sensing and Binding of Cyclic di-GMP by STING" on online Natural Structural and Molecular Biolo- gY. STING (stimulator of interferon genes) is an essential signaling adaptor that mediates cytokine pro- duction in response to microbial invasion by directly sensing bacterial secondary messengers such as the cy- clic dinucleotide bis-(3'-5')-cyclic dimeric GMP (e-di-GMP). STING's structure and its binding mecha- nism to cyclic dinucleotides were unknown. We report here the crystal structures of the STING cytoplas- mic domain and its complex with c-di-GMP, thus providing the structural basis for understanding STING function.

  7. Changes in SBPase activity influence photosynthetic capacity, growth, and tolerance to chilling stress in transgenic tomato plants

    Science.gov (United States)

    Ding, Fei; Wang, Meiling; Zhang, Shuoxin; Ai, Xizhen

    2016-01-01

    Sedoheptulose-1, 7-bisphosphatase (SBPase) is an important enzyme involved in photosynthetic carbon fixation in the Calvin cycle. Here, we report the impact of changes in SBPase activity on photosynthesis, growth and development, and chilling tolerance in SBPase antisense and sense transgenic tomato (Solanum lycopersicum) plants. In transgenic plants with increased SBPase activity, photosynthetic rates were increased and in parallel an increase in sucrose and starch accumulation was evident. Total biomass and leaf area were increased in SBPase sense plants, while they were reduced in SBPase antisense plants compared with equivalent wild-type tomato plants. Under chilling stress, when compared with plants with decreased SBPase activity, tomato plants with increased SBPase activity were found to be more chilling tolerant as indicated by reduced electrolyte leakage, increased photosynthetic capacity, and elevated RuBP regeneration rate and quantum efficiency of photosystem II. Collectively, our data suggest that higher level of SBPase activity gives an advantage to photosynthesis, growth and chilling tolerance in tomato plants. This work also provides a case study that an individual enzyme in the Calvin cycle may serve as a useful target for genetic engineering to improve production and stress tolerance in crops. PMID:27586456

  8. Changes in SBPase activity influence photosynthetic capacity, growth, and tolerance to chilling stress in transgenic tomato plants.

    Science.gov (United States)

    Ding, Fei; Wang, Meiling; Zhang, Shuoxin; Ai, Xizhen

    2016-01-01

    Sedoheptulose-1, 7-bisphosphatase (SBPase) is an important enzyme involved in photosynthetic carbon fixation in the Calvin cycle. Here, we report the impact of changes in SBPase activity on photosynthesis, growth and development, and chilling tolerance in SBPase antisense and sense transgenic tomato (Solanum lycopersicum) plants. In transgenic plants with increased SBPase activity, photosynthetic rates were increased and in parallel an increase in sucrose and starch accumulation was evident. Total biomass and leaf area were increased in SBPase sense plants, while they were reduced in SBPase antisense plants compared with equivalent wild-type tomato plants. Under chilling stress, when compared with plants with decreased SBPase activity, tomato plants with increased SBPase activity were found to be more chilling tolerant as indicated by reduced electrolyte leakage, increased photosynthetic capacity, and elevated RuBP regeneration rate and quantum efficiency of photosystem II. Collectively, our data suggest that higher level of SBPase activity gives an advantage to photosynthesis, growth and chilling tolerance in tomato plants. This work also provides a case study that an individual enzyme in the Calvin cycle may serve as a useful target for genetic engineering to improve production and stress tolerance in crops. PMID:27586456

  9. Electrophoretically deposited nano-structured polyaniline film for glucose sensing

    Energy Technology Data Exchange (ETDEWEB)

    Dhand, Chetna [Department of Science and Technology Centre on Biomolecular Electronics, Biomedical Instrumentation Section, Materials Physics and Engineering Division, National Physical Laboratory, Dr. K. S. Krishnan Marg, New Delhi-110012 (India); Department of Chemistry, University of Delhi, Delhi 110007 (India); Sumana, G. [Department of Science and Technology Centre on Biomolecular Electronics, Biomedical Instrumentation Section, Materials Physics and Engineering Division, National Physical Laboratory, Dr. K. S. Krishnan Marg, New Delhi-110012 (India); Datta, Monika [Department of Chemistry, University of Delhi, Delhi 110007 (India); Malhotra, B.D., E-mail: bansi.malhotra@gmail.co [Department of Science and Technology Centre on Biomolecular Electronics, Biomedical Instrumentation Section, Materials Physics and Engineering Division, National Physical Laboratory, Dr. K. S. Krishnan Marg, New Delhi-110012 (India); Centre for NanoBioEngineering and Spintronics, Chungnam National University, Daejeon, 305-764 (Korea, Republic of)

    2010-11-30

    Electrophoretically deposited nano-structured polyaniline (NS-PANI) film has been utilized for fabrication of glucose biosensor by covalent immobilization of glucose oxidase (GOx) using N-ethyl-N-(3-dimethylaminopropyl) carbodiimide and N-hydroxysuccinimide chemistry. This GOx/NS-PANI/ITO bioelectrode has been characterized using scanning electron microscopy, FT-IR, UV-Visible spectroscopy and differential pulse voltammetry (DPV) techniques. The response studies carried out on GOx/NS-PANI/ITO bioelectrode using DPV and photometric studies reveal linearity up to 400 mgdL{sup -1} with sensitivity as 1.05 x 10{sup -4} mA mg{sup -1} dL and 3.887 x 10{sup -5} Abs mg{sup -1} dL, respectively. The lower value of Michaelis-Menten constant obtained for immobilized GOx (2.1 mM) compared with that of free GOx (5.85 mM) suggests high affinity of enzyme to this matrix.

  10. Ethylene Production by Chilled Cucumbers (Cucumis sativus L.).

    Science.gov (United States)

    Wang, C Y; Adams, D O

    1980-11-01

    Chilling at 2.5 C accelerated the synthesis of 1-aminocyclopropane-1-carboxylic acid (ACC) and C(2)H(4) production in cucumber fruit. Skin tissue contained higher levels of ACC and was more sensitive to chilling than was cortex tissue. Accumulation of ACC in chilled tissue was detected after 1 day of chilling and remained elevated even after C(2)H(4) production started to decline. These data suggest that ACC synthesis is readily stimulated by chilling, whereas the system that converts ACC to C(2)H(4) is vulnerable to chilling injury. Chilling-induced C(2)H(4) production was inhibited by amino-ethoxyvinylglycine, sodium benzoate, propyl gallate, 2,4-dinitrophenol, carbonyl cyanide m-chlorophenylhydrazone, and cycloheximide. The utilization of methionine for ACC formation and chilling-induced C(2)H(4) biosynthesis was established using l-[3,4-(14)C]methionine. Chilled tissue had a higher capacity to convert l-[3,4-(14)C]methionine to ACC and C(2)H(4) than did nonchilled tissue. PMID:16661538

  11. Linking vegetation structure, function and physiology through spectroscopic remote sensing

    Science.gov (United States)

    Serbin, S.; Singh, A.; Couture, J. J.; Shiklomanov, A. N.; Rogers, A.; Desai, A. R.; Kruger, E. L.; Townsend, P. A.

    2015-12-01

    Terrestrial ecosystem process models require detailed information on ecosystem states and canopy properties to properly simulate the fluxes of carbon (C), water and energy from the land to the atmosphere and assess the vulnerability of ecosystems to perturbations. Current models fail to adequately capture the magnitude, spatial variation, and seasonality of terrestrial C uptake and storage, leading to significant uncertainties in the size and fate of the terrestrial C sink. By and large, these parameter and process uncertainties arise from inadequate spatial and temporal representation of plant traits, vegetation structure, and functioning. With increases in computational power and changes to model architecture and approaches, it is now possible for models to leverage detailed, data rich and spatially explicit descriptions of ecosystems to inform parameter distributions and trait tradeoffs. In this regard, spectroscopy and imaging spectroscopy data have been shown to be invaluable observational datasets to capture broad-scale spatial and, eventually, temporal dynamics in important vegetation properties. We illustrate the linkage of plant traits and spectral observations to supply key data constraints for model parameterization. These constraints can come either in the form of the raw spectroscopic data (reflectance, absorbtance) or physiological traits derived from spectroscopy. In this presentation we highlight our ongoing work to build ecological scaling relationships between critical vegetation characteristics and optical properties across diverse and complex canopies, including temperate broadleaf and conifer forests, Mediterranean vegetation, Arctic systems, and agriculture. We focus on work at the leaf, stand, and landscape scales, illustrating the importance of capturing the underlying variability in a range of parameters (including vertical variation within canopies) to enable more efficient scaling of traits related to functional diversity of ecosystems.

  12. Femtosecond laser induced refractive index structures in polymer optical fibre (POF) for sensing

    Science.gov (United States)

    Liang, S. J.; Scully, P. J.; Schille, J.; Vaughan, J.; Perrie, W.

    2009-10-01

    Techniques to directly write localised refractive index structures in polymer optical fibres (POF) are presented, using UV (400nm) ultrafast laser with pulse lengths of 100 fs to create in-fibre gratings for sensing. No doping is necessary for photosensitisation so commercially available POF is used. An in-fibre grating consisting of a 1.8 μm wide refractive index structure with a periodicity of 189 nm was demonstrated in single mode polymer fibre with optimised laser processing parameters.

  13. Simultaneous Damage Detection and Deflection Measurement of Morphing Wing Structures by Fiber Optic Sensing System

    OpenAIRE

    Djinovic, Zoran; Scheerer, Michael; Tomic, Milos; Stojkovic, Marijana; Schueller, Martin

    2014-01-01

    International audience; In this paper we present results of investigation of simultaneous damage detection and deflection measurement of morphing CFRP honeycomb structure by fiber optic sensing system developed in the frame of EU-FP7 project ÒFiber Optic System for Deflection and Damage Detection (FOS3D)î. The system is based on low- and high-coherence interferometry performed as Òall-in-fiberî sensing configuration. Raw signals have been on- and off-line processed by Òarctangî algorithm. Def...

  14. Towards a new structural model of the sense of humor: Preliminary findings

    OpenAIRE

    N D

    2012-01-01

    In this article some formal, content-related and procedural considerations towards the sense of humor are articulated and the analysis of both everyday humor behavior and of comic styles leads to the initial proposal of a four factor- model of humor (4FMH). This model is tested in a new dataset and it is also examined whether two forms of comic styles (benevolent humor and moral mockery) do fit in. The model seems to be robust but further studies on the structure of the sense of humor as a pe...

  15. Shape and Stress Sensing of Multilayered Composite and Sandwich Structures Using an Inverse Finite Element Method

    Science.gov (United States)

    Cerracchio, Priscilla; Gherlone, Marco; Di Sciuva, Marco; Tessler, Alexander

    2013-01-01

    The marked increase in the use of composite and sandwich material systems in aerospace, civil, and marine structures leads to the need for integrated Structural Health Management systems. A key capability to enable such systems is the real-time reconstruction of structural deformations, stresses, and failure criteria that are inferred from in-situ, discrete-location strain measurements. This technology is commonly referred to as shape- and stress-sensing. Presented herein is a computationally efficient shape- and stress-sensing methodology that is ideally suited for applications to laminated composite and sandwich structures. The new approach employs the inverse Finite Element Method (iFEM) as a general framework and the Refined Zigzag Theory (RZT) as the underlying plate theory. A three-node inverse plate finite element is formulated. The element formulation enables robust and efficient modeling of plate structures instrumented with strain sensors that have arbitrary positions. The methodology leads to a set of linear algebraic equations that are solved efficiently for the unknown nodal displacements. These displacements are then used at the finite element level to compute full-field strains, stresses, and failure criteria that are in turn used to assess structural integrity. Numerical results for multilayered, highly heterogeneous laminates demonstrate the unique capability of this new formulation for shape- and stress-sensing.

  16. Real time sensing of structural glass fiber reinforced composites by using embedded PVA - carbon nanotube fibers

    Directory of Open Access Journals (Sweden)

    Marioli-Riga Z.

    2010-06-01

    Full Text Available Polyvinyl alcohol - carbon nanotube (PVA-CNT fibers had been embedded to glass fiber reinforced polymers (GFRP for the structural health monitoring of the composite material. The addition of the conductive PVA-CNT fiber to the nonconductive GFRP material aimed to enhance its sensing ability by means of the electrical resistance measurement method. The test specimen’s response to mechanical load and the in situ PVA-CNT fiber’s electrical resistance measurements were correlated for sensing and damage monitoring purposes. The embedded PVA-CNT fiber worked as a sensor in GFRP coupons in tensile loadings. Sensing ability of the PVA-CNT fibers was also demonstrated on an integral composite structure. PVA-CNT fiber near the fracture area of the structure recorded very high values when essential damage occurred to the structure. A finite element model of the same structure was developed to predict axial strains at locations of the integral composite structure where the fibers were embedded. The predicted FEA strains were correlated with the experimental measurements from the PVA-CNT fibers. Calculated and experimental values were in good agreement, thus enabling PVA-CNT fibers to be used as strain sensors.

  17. ZnO-coated SMS structure interrogated by a fiber ring laser for chemical sensing

    Science.gov (United States)

    Wen, X. Y.; Huang, J.; Xiao, H.; Yang, M. H.

    2014-11-01

    A zinc oxide (ZnO)-coated single mode-multimode-single mode fiber (SMS) structure interrogated by a fiber ring laser has been developed as a chemical sensor. Response to relative humidity (RH) and ethanol volatilization was evaluated by tracking the wavelength shifts of the output laser line in different moisture environments and ethanol solutions, respectively. For humidity sensing a linear response with a measurement range of 4-96% RH, and a sensitivity of 0.06 nm per %RH were obtained. As for ethanol volatilization sensing obvious wavelength blue shift was observed for the sensor immersed in 50% and 62% ethanol solution, while no variation could be detected in pure ethanol solution (purity larger than 97%). With the advantages of low cost, ease of fabrication and sensitive response, ZnO-coated SMS interrogated with a fiber ring laser was demonstrated to be an effective sensor for humidity and ethanol volatilization sensing.

  18. ZnO-coated SMS structure interrogated by a fiber ring laser for chemical sensing

    International Nuclear Information System (INIS)

    A zinc oxide (ZnO)-coated single mode–multimode–single mode fiber (SMS) structure interrogated by a fiber ring laser has been developed as a chemical sensor. Response to relative humidity (RH) and ethanol volatilization was evaluated by tracking the wavelength shifts of the output laser line in different moisture environments and ethanol solutions, respectively. For humidity sensing a linear response with a measurement range of 4–96% RH, and a sensitivity of 0.06 nm per %RH were obtained. As for ethanol volatilization sensing obvious wavelength blue shift was observed for the sensor immersed in 50% and 62% ethanol solution, while no variation could be detected in pure ethanol solution (purity larger than 97%). With the advantages of low cost, ease of fabrication and sensitive response, ZnO-coated SMS interrogated with a fiber ring laser was demonstrated to be an effective sensor for humidity and ethanol volatilization sensing. (paper)

  19. Fully integrated patterned carbon nanotube strain sensors on flexible sensing skin substrates for structural health monitoring

    Science.gov (United States)

    Burton, Andrew R.; Kurata, Masahiro; Nishino, Hiromichi; Lynch, Jerome P.

    2016-04-01

    New advances in nanotechnology and material processing is creating opportunities for the design and fabrication of a new generation of thin film sensors that can used to assess structural health. In particular, thin film sensors attached to large areas of the structure surface has the potential to provide spatially rich data on the performance and health of a structure. This study focuses on the development of a fully integrated strain sensor that is fabricated on a flexible substrate for potentially use in sensing skins. This is completed using a carbon nanotube-polymer composite material that is patterned on a flexible polyimide substrate using optical lithography. The piezoresistive carbon nanotube elements are integrated into a complete sensing system by patterning copper electrodes and integrating off-the-shelf electrical components on the flexible film for expanded functionality. This diverse material utilization is realized in a versatile process flow to illustrate a powerful toolbox for sensing severity, location, and failure mode of damage on structural components. The fully integrated patterned carbon nanotube strain sensor is tested on a quarter-scale, composite beam column connection. The results and implications for future structural damage detection are discussed.

  20. Performance of a chill ATES system

    Energy Technology Data Exchange (ETDEWEB)

    Midkiff, K.C.; Song, Y.K.; Schaetzle, W.J. [Univ. of Alabama, Tuscaloosa, AL (United States)] [and others

    1989-03-01

    An aquifer air-conditioning system has been installed to cool the Student Recreation Center on the University of Alabama Campus. This research program encompasses the monitoring of the operation of the aquifer system and provision of emplacements to the system. The monitoring includes establishing the instrumentation, acquiring data, and analyzing the results. The instrumentation allows the measurement of water flow rates and corresponding temperatures, electrical energy input, aquifer temperatures at nineteen monitoring wells, and aquifer levels at six monitoring wells. Recent acquifer performance data indicate that 76% of the chill energy stored was recovered for the period Oct/86 - Sep/87 and 70% for the period Oct/87 - Sep/88. This is a substantial improvement over recoveries of 38% for the 1985 season and 55% for 1986. The overall coefficient of performance was 5.4 for Oct/86 - Sep/87 and 4.6 for Oct/87 - Sep/88. THe system has supplied 100% of the cooling with only about one-half of the energy input required by a conventional system. Some of the increased recovery of chilled water is a result of modifying the production well operation to reduce the regional flow of water toward the northwest. All warm water is withdrawn form the southeast wells, chilled, and injected in northwest wells. The cold water then withdrawn from the cold wells is used for air-conditioning but not reinjected into the aquifer. Additional flow control is provided by pumping (and discarding) water out of a southeast well, although the complete results of this new strategy are as yet unclear.

  1. Chilled Ammonia Process for CO2 Capture

    DEFF Research Database (Denmark)

    Darde, Victor Camille Alfred; Thomsen, Kaj; Well, Willy J.M. van;

    2010-01-01

    The chilled ammonia process absorbs the CO2 at low temperature (2–10°C). The heat of absorption of carbon dioxide by ammonia is significantly lower than for amines. In addition, degradation problems can be avoided and a high carbon dioxide capacity is achieved. Hence, this process shows good...... and pressure up to 100bars. The results show that solid phases consisting of ammonium carbonate and bicarbonate are formed in the absorber. The heat requirements in the absorber and in the desorber have been studied. The enthalpy calculations show that a heat requirement for the desorber lower than 2GJ/ton CO2...

  2. Chilled ammonia process for CO2 capture

    DEFF Research Database (Denmark)

    Darde, Victor Camille Alfred; Thomsen, Kaj; van Well, Willy J. M;

    2009-01-01

    The chilled ammonia process absorbs the CO2 at low temperature (2-10 degrees C). The heat of absorption of carbon dioxide by ammonia is significantly lower than for amines. In addition, degradation problems can be avoided and a high carbon dioxide capacity is achieved. Hence, this process shows...... C and pressure up to 100 bars [1]. The results show that solid phases consisting of ammonium carbonate and bicarbonate are formed in the absorber. The energy requirements in the absorber and in the desorber have been studied. The enthalpy calculations show that an energy requirement for the desorber...

  3. Synthesis of nestlike ZnO hierarchically porous structures and analysis of their gas sensing properties.

    Science.gov (United States)

    Wang, Xinzhen; Liu, Wei; Liu, Jiurong; Wang, Fenglong; Kong, Jing; Qiu, Song; He, Cuizhu; Luan, Liqiang

    2012-02-01

    Nestlike 3D ZnO porous structures with size of 1.0-3.0 μm have been synthesized through annealing the zinc hydroxide carbonate precursor, which was obtained by a one-pot hydrothermal process with the assistance of glycine, Na(2)SO(4), and polyvinyl pyrrolidone (PVP). The nestlike 3D ZnO structures are built of 2D nanoflakes with the thickness of ca. 20 nm, which exhibit the nanoporous wormhole-like characteristic. The measured surface area is 36.4 m(2)g(-1) and the pore size is ca. 3-40 nm. The unique nestlike 3D ZnO porous structures provided large contacting surface area for electrons, oxygen and target gas molecules, and abundant channels for gas diffusion and mass transport. Gas sensing tests showed that the nestlike 3D ZnO porous structures exhibit excellent gas sensing performances such as high sensitivity and fast response and recovery speed, suggesting the potential applications as advanced gas sensing materials. PMID:22216881

  4. Piezoelectric-based smart sensing system for I-beam structural health monitoring

    Science.gov (United States)

    Zhang, Chen; Zhang, Haifeng; Yu, Tzuyang; Wang, Xingwei

    2016-04-01

    In recent decades, the I-beam has become one of the most important engineering structural components being applied in areas such as mechanical, civil, and constructional engineering. To ensure safety and proper maintenance, an effective and accurate structural health monitoring method/system for I-beams is urgently needed. This paper proposes a smart sensing system for I-beam crack detection that is based on the energy diffusivity (attenuation) between two individual piezoelectric transducers (PZTs). Sensor (one of the PZTs) responses are analyzed and applied to characterize the health status of the I-beam. Lab experiments are carried out for effective evaluation of this approach in structural health monitoring. The characteristics of crack distribution are studied by calculating and analyzing the energy diffusivity variation of the sensor responses to artificially cuttings to the I-beam. Moreover, instead of utilizing an actuator and a sensor, the system employs a couple of PZTs sensors, which offer the potential for in-field, in situ sensing with the sensor arrays. This smart sensing system can be applied in railway, metro, and iron-steel structures for I-beam health monitoring applications.

  5. Chilling and heat requirements for flowering in temperate fruit trees.

    Science.gov (United States)

    Guo, Liang; Dai, Junhu; Ranjitkar, Sailesh; Yu, Haiying; Xu, Jianchu; Luedeling, Eike

    2014-08-01

    Climate change has affected the rates of chilling and heat accumulation, which are vital for flowering and production, in temperate fruit trees, but few studies have been conducted in the cold-winter climates of East Asia. To evaluate tree responses to variation in chill and heat accumulation rates, partial least squares regression was used to correlate first flowering dates of chestnut (Castanea mollissima Blume) and jujube (Zizyphus jujube Mill.) in Beijing, China, with daily chill and heat accumulation between 1963 and 2008. The Dynamic Model and the Growing Degree Hour Model were used to convert daily records of minimum and maximum temperature into horticulturally meaningful metrics. Regression analyses identified the chilling and forcing periods for chestnut and jujube. The forcing periods started when half the chilling requirements were fulfilled. Over the past 50 years, heat accumulation during tree dormancy increased significantly, while chill accumulation remained relatively stable for both species. Heat accumulation was the main driver of bloom timing, with effects of variation in chill accumulation negligible in Beijing’s cold-winter climate. It does not seem likely that reductions in chill will have a major effect on the studied species in Beijing in the near future. Such problems are much more likely for trees grown in locations that are substantially warmer than their native habitats, such as temperate species in the subtropics and tropics.

  6. 76 FR 166 - Fresh and Chilled Atlantic Salmon From Norway

    Science.gov (United States)

    2011-01-03

    ... imports of fresh and chilled Atlantic salmon from Norway (56 FR 14920, 14921). Following five-year reviews... imports of fresh and chilled Atlantic salmon from Norway (71 FR 7512). The Commission is now conducting...), as most recently amended at 74 FR 2847 (January 16, 2009). \\1\\ \\1\\ No response to this request...

  7. Mechanism of silicon influence on the chill of cast iron

    Directory of Open Access Journals (Sweden)

    E. Fraś

    2007-12-01

    Full Text Available In this work an analytical solution of general validity is used to explain mechanism of the silicon influence on the absolute chill tendency (CT and chill (w of cast iron. It is found that CT can be related to nucleation potential of graphite (Nv, growth parameter (μ of eutectic cells, temperature range (ΔTsc and the pre-eutectic austenite volume fraction (fγ. It has been shown that silicon additions: a impede the growth of graphite eutectic cells, μ, b expands the temperature range ΔTsc, c increases the nucleation potential of graphite Nv, d lowers the pre-eutectic austenite volume fraction, fγ. and in consequence the absolute chilling tendency, CT decreases. The minimum wall thicknesses for chilled castings, or chill widths (w in wedge shaped castings is related to CT and as silcon contents increases, the w value also increases.

  8. DuraNode: wireless-networked sensing system for structural safety monitoring

    Science.gov (United States)

    Chung, H.; Park, C.; Xie, Q.; Chou, P.; Shinozuka, M.

    2005-05-01

    DuraNode is a sensing system designed for structural monitoring. It can detect the damage of structural members, provide crucial intelligence information of structural integrity and activate emergency response mechanism in the initial stages of a disaster. The sensor encompasses three MEMS-type accelerometers (SD-1221) and Wi-Fi (802.11b) communication adapter. It operates on solar power and rechargeable battery making it last for long term service without battery replacement. DuraNodes can be deployed in the form of a dense wireless network to enable seamless acquisition of structural intelligence in a complex structural system. A preliminary data acquisition and signal display module with graphic user interface (GUI) has been developed for connection of access points in ad-hoc networking. To validate the performance of DuraNode in structural monitoring applications, experiments were conducted on measuring vibration of a Pedestrian bridge in UC, Irvine, and a two-column bridge bent specimen with a Shake-table test in University of Neveda, Reno. Results were compared with that from conventional wired sensors and showed that DuraNode is cost-effective for carrying out robust sensing functions in the structural safety monitoring missions.

  9. Real time sensing of structural glass fiber reinforced composites by using embedded PVA - carbon nanotube fibers

    OpenAIRE

    Marioli-Riga Z.; Bartholome C.; Alexopoulos N.; Poulin P.

    2010-01-01

    Polyvinyl alcohol - carbon nanotube (PVA-CNT) fibers had been embedded to glass fiber reinforced polymers (GFRP) for the structural health monitoring of the composite material. The addition of the conductive PVA-CNT fiber to the nonconductive GFRP material aimed to enhance its sensing ability by means of the electrical resistance measurement method. The test specimen’s response to mechanical load and the in situ PVA-CNT fiber’s electrical resistance measurements were correlated for sens...

  10. Structural Health Monitoring of Civil Infrastructure Using Optical Fiber Sensing Technology: A Comprehensive Review

    OpenAIRE

    Ye, X. W.; Su, Y. H.; Han, J. P.

    2014-01-01

    In the last two decades, a significant number of innovative sensing systems based on optical fiber sensors have been exploited in the engineering community due to their inherent distinctive advantages such as small size, light weight, immunity to electromagnetic interference (EMI) and corrosion, and embedding capability. A lot of optical fiber sensor-based monitoring systems have been developed for continuous measurement and real-time assessment of diversified engineering structures such as b...

  11. Nut crop yield records show that budbreak-based chilling requirements may not reflect yield decline chill thresholds

    Science.gov (United States)

    Pope, Katherine S.; Dose, Volker; Da Silva, David; Brown, Patrick H.; DeJong, Theodore M.

    2015-06-01

    Warming winters due to climate change may critically affect temperate tree species. Insufficiently cold winters are thought to result in fewer viable flower buds and the subsequent development of fewer fruits or nuts, decreasing the yield of an orchard or fecundity of a species. The best existing approximation for a threshold of sufficient cold accumulation, the "chilling requirement" of a species or variety, has been quantified by manipulating or modeling the conditions that result in dormant bud breaking. However, the physiological processes that affect budbreak are not the same as those that determine yield. This study sought to test whether budbreak-based chilling thresholds can reasonably approximate the thresholds that affect yield, particularly regarding the potential impacts of climate change on temperate tree crop yields. County-wide yield records for almond ( Prunus dulcis), pistachio ( Pistacia vera), and walnut ( Juglans regia) in the Central Valley of California were compared with 50 years of weather records. Bayesian nonparametric function estimation was used to model yield potentials at varying amounts of chill accumulation. In almonds, average yields occurred when chill accumulation was close to the budbreak-based chilling requirement. However, in the other two crops, pistachios and walnuts, the best previous estimate of the budbreak-based chilling requirements was 19-32 % higher than the chilling accumulations associated with average or above average yields. This research indicates that physiological processes beyond requirements for budbreak should be considered when estimating chill accumulation thresholds of yield decline and potential impacts of climate change.

  12. Demonstration of UAV deployment and control of mobile wireless sensing networks for modal analysis of structures

    Science.gov (United States)

    Zhou, Hao; Hirose, Mitsuhito; Greenwood, William; Xiao, Yong; Lynch, Jerome; Zekkos, Dimitrios; Kamat, Vineet

    2016-04-01

    Unmanned aerial vehicles (UAVs) can serve as a powerful mobile sensing platform for assessing the health of civil infrastructure systems. To date, the majority of their uses have been dedicated to vision and laser-based spatial imaging using on-board cameras and LiDAR units, respectively. Comparatively less work has focused on integration of other sensing modalities relevant to structural monitoring applications. The overarching goal of this study is to explore the ability for UAVs to deploy a network of wireless sensors on structures for controlled vibration testing. The study develops a UAV platform with an integrated robotic gripper that can be used to install wireless sensors in structures, drop a heavy weight for the introduction of impact loads, and to uninstall wireless sensors for reinstallation elsewhere. A pose estimation algorithm is embedded in the UAV to estimate the location of the UAV during sensor placement and impact load introduction. The Martlet wireless sensor network architecture is integrated with the UAV to provide the UAV a mobile sensing capability. The UAV is programmed to command field deployed Martlets, aggregate and temporarily store data from the wireless sensor network, and to communicate data to a fixed base station on site. This study demonstrates the integrated UAV system using a simply supported beam in the lab with Martlet wireless sensors placed by the UAV and impact load testing performed. The study verifies the feasibility of the integrated UAV-wireless monitoring system architecture with accurate modal characteristics of the beam estimated by modal analysis.

  13. Effect of modification melt treatment on casting/chill interfacial heat transfer and electrical conductivity of Al-13% Si alloy

    Energy Technology Data Exchange (ETDEWEB)

    Narayan Prabhu, K.; Ravishankar, B.N

    2003-11-15

    For successful modelling of the solidification process, a reliable heat transfer boundary condition data is required. These boundary conditions are significantly influenced by the casting and mould parameters. In the present work, the effect of sodium modification melt treatment on casting/chill interfacial heat transfer during upward solidification of an Al-13% Si alloy against metallic chills is investigated using thermal analysis and inverse modelling techniques. In the presence of chills, modification melt treatment resulted in an increase in the cooling rate of the solidifying casting near the casting/chill interfacial region. The corresponding interfacial heat flux transients and electrical conductivities are also found to be higher. This is attributed to (i) improvement in the casting/chill interfacial thermal contact condition brought about by the decrease in the surface tension of the liquid metal on addition of sodium and (ii) increase in the electronic heat conduction in the initial solidified shell due to change in the morphology of silicon from a acicular type to a fine fibrous structure and increase in the ratio of the modification rating to the secondary dendrite arm spacing.

  14. School Starters’ Early Structure Sense (Sentido estructural temprano de estudiantes al inicio de su escolarización)

    OpenAIRE

    Lüken, Miriam M.

    2012-01-01

    Low and high achieving children’s competences regarding pattern and structure at the beginning of formal schooling are comparatively analyzed in order to evaluate the range of school starters’ early structure sense. The results suggest overall high pre-instructional competences which, however, differ strongly between the mathematical high and low achievers. Cognitive milestones for the development of a sound early structure sense are named.Las competencias relacionadas con patrones y estructu...

  15. A Plasmonic Temperature-Sensing Structure Based on Dual Laterally Side-Coupled Hexagonal Cavities

    Directory of Open Access Journals (Sweden)

    Yiyuan Xie

    2016-05-01

    Full Text Available A plasmonic temperature-sensing structure, based on a metal-insulator-metal (MIM waveguide with dual side-coupled hexagonal cavities, is proposed and numerically investigated by using the finite-difference time-domain (FDTD method in this paper. The numerical simulation results show that a resonance dip appears in the transmission spectrum. Moreover, the full width of half maximum (FWHM of the resonance dip can be narrowed down, and the extinction ratio can reach a maximum value by tuning the coupling distance between the waveguide and two cavities. Based on a linear relationship between the resonance dip and environment temperature, the temperature-sensing characteristics are discussed. The temperature sensitivity is influenced by the side length and the coupling distance. Furthermore, for the first time, two concepts—optical spectrum interference (OSI and misjudge rate (MR—are introduced to study the temperature-sensing resolution based on spectral interrogation. This work has some significance in the design of nanoscale optical sensors with high temperature sensitivity and a high sensing resolution.

  16. A Plasmonic Temperature-Sensing Structure Based on Dual Laterally Side-Coupled Hexagonal Cavities.

    Science.gov (United States)

    Xie, Yiyuan; Huang, Yexiong; Xu, Weihua; Zhao, Weilun; He, Chao

    2016-01-01

    A plasmonic temperature-sensing structure, based on a metal-insulator-metal (MIM) waveguide with dual side-coupled hexagonal cavities, is proposed and numerically investigated by using the finite-difference time-domain (FDTD) method in this paper. The numerical simulation results show that a resonance dip appears in the transmission spectrum. Moreover, the full width of half maximum (FWHM) of the resonance dip can be narrowed down, and the extinction ratio can reach a maximum value by tuning the coupling distance between the waveguide and two cavities. Based on a linear relationship between the resonance dip and environment temperature, the temperature-sensing characteristics are discussed. The temperature sensitivity is influenced by the side length and the coupling distance. Furthermore, for the first time, two concepts-optical spectrum interference (OSI) and misjudge rate (MR)-are introduced to study the temperature-sensing resolution based on spectral interrogation. This work has some significance in the design of nanoscale optical sensors with high temperature sensitivity and a high sensing resolution.

  17. Using an SU-8 Photoresist Structure and Cytochrome C Thin Film Sensing Material for a Microbolometer

    Directory of Open Access Journals (Sweden)

    Guo-Dung John Su

    2012-11-01

    Full Text Available There are two critical parameters for microbolometers: the temperature coefficient of resistance (TCR of the sensing material, and the thermal conductance of the insulation structure. Cytochrome c protein, having a high TCR, is a good candidate for infrared detection. We can use SU-8 photoresist for the thermal insulation structure, given its low thermal conductance. In this study, we designed a platform structure based on a SU-8 photoresist. We fabricated an infrared sensing pixel and recorded a high TCR for this new structure. The SU-8 photoresist insulation structure was fabricated using the exposure dose method. We experimentally demonstrated high values of TCR from 22%/K to 25.7%/K, and the measured noise was 1.2 × 10–8 V2/Hz at 60 Hz. When the bias current was 2 μA, the calculated voltage responsivity was 1.16 × 105 V/W. This study presents a new kind of microbolometer based on cytochrome c protein on top of an SU-8 photoresist platform that does not require expensive vacuum deposition equipment.

  18. Hybrid networking sensing system for structural health monitoring of a concrete cable-stayed bridge

    Science.gov (United States)

    Torbol, Marco; Kim, Sehwan; Chien, Ting-Chou; Shinozuka, Masanobu

    2013-04-01

    The purpose of this study is the remote structural health monitoring to identify the torsional natural frequencies and mode shapes of a concrete cable-stayed bridge using a hybrid networking sensing system. The system consists of one data aggregation unit, which is daisy-chained to one or more sensing nodes. A wireless interface is used between the data aggregation units, whereas a wired interface is used between a data aggregation unit and the sensing nodes. Each sensing node is equipped with high-precision MEMS accelerometers with adjustable sampling frequency from 0.2 Hz to 1.2 kHz. The entire system was installed inside the reinforced concrete box-girder deck of Hwamyung Bridge, which is a cable stayed bridge in Busan, South Korea, to protect the system from the harsh environmental conditions. This deployment makes wireless communication a challenge due to the signal losses and the high levels of attenuation. To address these issues, the concept of hybrid networking system is introduced with the efficient local power distribution technique. The theoretical communication range of Wi-Fi is 100m. However, inside the concrete girder, the peer to peer wireless communication cannot exceed about 20m. The distance is further reduced by the line of sight between the antennas. However, the wired daisy-chained connection between sensing nodes is useful because the data aggregation unit can be placed in the optimal location for transmission. To overcome the limitation of the wireless communication range, we adopt a high-gain antenna that extends the wireless communication distance to 50m. Additional help is given by the multi-hopping data communication protocol. The 4G modem, which allows remote access to the system, is the only component exposed to the external environment.

  19. Structural interactions between lipids, water and S1-S4 voltage-sensing domains.

    Science.gov (United States)

    Krepkiy, Dmitriy; Gawrisch, Klaus; Swartz, Kenton J

    2012-11-01

    Membrane proteins serve crucial signaling and transport functions, yet relatively little is known about their structures in membrane environments or how lipids interact with these proteins. For voltage-activated ion channels, X-ray structures suggest that the mobile voltage-sensing S4 helix would be exposed to the membrane, and functional studies reveal that lipid modification can profoundly alter channel activity. Here, we use solid-state NMR to investigate structural interactions of lipids and water with S1-S4 voltage-sensing domains and to explore whether lipids influence the structure of the protein. Our results demonstrate that S1-S4 domains exhibit extensive interactions with lipids and that these domains are heavily hydrated when embedded in a membrane. We also find evidence for preferential interactions of anionic lipids with S1-S4 domains and that these interactions have lifetimes on the timescale of ≤ 10(-3)s. Arg residues within S1-S4 domains are well hydrated and are positioned in close proximity to lipids, exhibiting local interactions with both lipid headgroups and acyl chains. Comparative studies with a positively charged lipid lacking a phosphodiester group reveal that this lipid modification has only modest effects on the structure and hydration of S1-S4 domains. Taken together, our results demonstrate that Arg residues in S1-S4 voltage-sensing domains reside in close proximity to the hydrophobic interior of the membrane yet are well hydrated, a requirement for carrying charge and driving protein motions in response to changes in membrane voltage.

  20. Gas Sensing with Bare and Graphene-covered Optical Nano-Antenna Structures

    Science.gov (United States)

    Mehta, Bhaven; Benkstein, Kurt D.; Semancik, Steve; Zaghloul, Mona E.

    2016-02-01

    The motivation behind this work is to study the gas phase chemical sensing characteristics of optical (plasmonic) nano-antennas (ONA) and graphene/graphene oxide-covered versions of these structures. ONA are devices that have their resonating frequency in the visible range. The basic principle governing the detection mechanism for ONA is refractive index sensing. The change in the concentration of the analyte results in a differing amount of adsorbate and correlated shifts in the resonance wavelength of the device. In this work, bare and graphene or graphene oxide covered ONA have been evaluated for gas sensing performance. Four different analytes (ethanol, acetone, nitrogen dioxide and toluene) were used in testing. ONA response behavior to different analytes was modified by adsorption within the graphene and graphene oxide overlayers. This work is a preliminary study to understand resonance wavelength shift caused by different analytes. Results imply that the combination of well-structured ONA functionalized by graphene-based adsorbers can give sensitive and selective sensors but baseline drift effects identified in this work must be addressed for applied measurements.

  1. The structure of sensor organic polymeric solids deposited on surfaces of interest for sensing devices

    CERN Document Server

    Lemon, P

    2001-01-01

    For many years, electrochemically deposited polypyrrole has found application in a host of technologically significant areas. Popular applications include use in rechargeable batteries, electrochromic displays and artificial muscles. However, perhaps the most significant application of polypyrrole is as a gas sensing material. The relatively low selectivity of polypyrrole has led to it seldom being used as a 'stand alone' sensor; the ease by which the properties of polypyrrole may be subtly modified during electrochemical deposition (resulting in subtly different sensor responses) makes it ideally suited for incorporation into sensing 'arrays'. The level of understanding concerning the growth dynamics and structural characteristics of electrochemically deposited polypyrrole was poor prior to the commencement of the work presented; this thesis describes research undertaken in order to elucidate the properties of this material. As variation of the dopant group used during electrochemical deposition has been sho...

  2. Sensing Properties of a Fabry-Perot Dielectric Structure and Dimer Nanoparticles

    Directory of Open Access Journals (Sweden)

    A. Polemi

    2012-01-01

    Full Text Available We investigate the use of a Fabry-Perot dielectric structure combined with differently shaped nanoparticles for Surface Enhanced Raman Scattering. In particular, we show how an ideal two-layer Fabry-Perot configuration enhances the local surface field of silver nanoparticles positioned on the surface of the structure. We develop the concept using disc dimers and then extend the discussion to bowtie nanoparticles. The structure is excited by a single emitter, which couples to the nanoparticles through the dielectric layers, producing a wide aperture field that can be used to excite multiple dimers. We show how an array of nanoparticles can be properly arranged in order to increase the total scattering signal generated from the structure. The layered geometry produces robust field properties in between nanoparticles, making the overall sensing characteristics less sensitive to the interparticle seperation distance and incident polarization.

  3. Reseptioptimointi cook and chill -tuotantotapaan : Case: Kolarin keskuskeittiö

    OpenAIRE

    Pääkkölä, Henna

    2010-01-01

    Opinnäytetyön tarkoituksena oli perehtyä cook and chill -tuotantotapaan ja tutkia sen vaikutuksia reseptioptimointiin. Tavoitteena oli selvittää cook and chill -tuotantotavan etuja ja mahdollisia haasteita ammattikeittiön ruokatuotannossa sekä tuottaa aiheesta tietoa suomenkielisiä lukijoita varten. Opinnäytetyön tavoitteena oli myös optimoida Kolarin keskuskeittiön lounasruokalistan lämpimille aterioille cook and chill -tuotantotapaan soveltuvat ruokaohjeet sekä valmistusprosessikuvaukset. T...

  4. Deciduous Forest Structure Estimated with LIDAR-Optimized Spectral Remote Sensing

    Directory of Open Access Journals (Sweden)

    Jason Defibaugh y Chávez

    2013-01-01

    Full Text Available Coverage and frequency of remotely sensed forest structural information would benefit from single orbital platforms designed to collect sufficient data. We evaluated forest structural information content using single-date Hyperion hyperspectral imagery collected over full-canopy oak-hickory forests in the Ozark National Forest, Arkansas, USA. Hyperion spectral derivatives were used to develop machine learning regression tree rule sets for predicting forest neighborhood percentile heights generated from near-coincident Leica Geosystems ALS50 small footprint light detection and ranging (LIDAR. The most successful spectral predictors of LIDAR-derived forest structure were also tested with basal area measured in situ. Based on the machine learning regression trees developed, Hyperion spectral derivatives were utilized to predict LIDAR forest neighborhood percentile heights with accuracies between 2.1 and 3.7 m RMSE. Understory predictions consistently resulted in the highest accuracy of 2.1 m RMSE. In contrast, hyperspectral prediction of basal area measured in situ was only found to be 6.5 m2/ha RMSE when the average basal area across the study area was ~12 m2/ha. The results suggest, at a spatial resolution of 30 × 30 m, that orbital hyperspectral imagery alone can provide useful structural information related to vegetation height. Rapidly calibrated biophysical remote sensing techniques will facilitate timely assessment of regional forest conditions.

  5. Interpretation of remote sensing of geological structures and prediction of gold mineralization in Mohe area and its adjacent region

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The authors took the ETM+ multi-spectra data as the data information and correlation coefficient for each band and carried out their information volume statistics. According to certain criteria, the authors also determined the optimum band-combined image. The image clarity is improved by various enhancements and fusions method. Based on remote sensing geological interpretation in detail, the relationship between remote sensing geological characters and gold mine were analyzed systemically. Using all kinds of remote sensing structure information, combining other research data, the authors determined mainly ore-controlling ore structure. Several prospective areas of gold ores were determined and furthermore significant finding mine target areas was confirmed.

  6. Human perception of indoor environment generated by chilled ceiling combined with mixing ventilation or localised chilled beam under cooling mode

    DEFF Research Database (Denmark)

    Bolashikov, Zhecho Dimitrov; Nygaard, Linette; Uth, Simon C.;

    2014-01-01

    Experiments with 24 subjects were performed to study and compare the human perception of the indoor environment under summer conditions generated by a chilled ceiling combined with overhead mixing ventilation and localised chilled beam. The experiments were performed in an experimental chamber (4....../s during the 20 min period of physical activity, when the occupant was not at the desk with the localised chilled beam, resulting in increase of the air temperature in the room. Subjects used questionnaires to answer on thermal sensation and acceptability, perceived air quality, air movement and SBS...

  7. Impact of interfacial interactions on optical and ammonia sensing in zinc oxide/polyaniline structures

    Indian Academy of Sciences (India)

    Mansi Dhingra; Lalit Kumar; Sadhna Shrivastava; P Senthil Kumar; S Annapoorni

    2013-08-01

    Zinc oxide/polyaniline (ZnO/PANI) hybrid structures have been investigated for their optical and gas sensing properties. ZnO nanoparticles, prepared by the sol–gel method, pressed in the form of pellets were used for gas sensing. The hybrid ZnO/PANI structure was obtained by the addition of PANI on the surface of ZnO. The UV–Vis absorption of the modified pellets show band edge at 363 nm corresponding to ZnO, while a change in the absorption peaks for PANI was observed. The possible interaction between Zn2+ of ZnO and NH-group of PANI was confirmed using Raman spectroscopy studies. The results reveal that the hybrid structures exhibit much higher sensitivity to NH3 gas at room temperature than blank ZnO, which is sensitive to NH3 gas at higher temperature. This enhancement has been attributed to the creation of active sites on the ZnO surface due to the presence of PANI.

  8. Integrated remote sensing data utilization for investigating structural and tectonic history of the Ghadames Basin, Libya

    Science.gov (United States)

    Saadi, N. M.; Zaher, M. Abdel; El-Baz, F.; Watanabe, K.

    2011-10-01

    This study was initiated to constrain the geological structure of the Ghadames Basin in northwest Libya. Detailed analysis was based on digital integration of surface data, including SRTM DEM, ETM+ and geologic maps with subsurface data, including well logs and potential field data. Integrated analysis of remotely sensed data of the SRTM and ETM+ were utilized to identify geologic lineaments in the area. Ground-based verification of the remote sensing data was achieved with field work. Interpretation and analysis of the lineaments indicate that the Ghadames Basin is controlled by four main fault systems that trend WNW, NNW, NW and ENE. Well logs and potential field data were used to delineate a detailed picture of the subsurface structure. The potential field data reveal two NE and NNE trending sedimentary basins. The depth of the basement inside the main basin ranges from 2 to 6 km. A two-dimensional (2-D) schematic model shows that the basin gradually deepens towards the southwest. The applied data integration gave new insight into the tectonic and structure patterns of the Ghadames Basin and the adjacent areas of northwest Libya.

  9. Structural plasticity and dynamic selectivity of acid sensing ion channel–toxin complexes

    OpenAIRE

    Baconguis, Isabelle; Gouaux, Eric

    2012-01-01

    Acid sensing ion channels (ASICs) are voltage-independent, amiloride-sensitive channels implicated in diverse physiological processes ranging from nociception to taste. Despite the importance of ASICs in physiology, we know little about the mechanism of channel activation. Here we show that psalmotoxin activates non- and sodium-selective currents in chicken ASIC1a at pH 7.25 and 5.5, respectively. Crystal structures of ASIC1a – psalmotoxin complexes map the toxin binding site to the extracell...

  10. Mesoporous In2O3: Effect of Material Structure on the Gas Sensing

    OpenAIRE

    Cheng, Z. X.; Ren, X. H.; J. Q. Xu; Pan, Q. Y.

    2011-01-01

    We present a semiconductor gas sensor based on mesoporous In2O3 (m-In2O3). The m-In2O3 was successfully fabricated by a simple sol-gel process, using block copolymer PE6800 as a soft template. The results of gas sensing reveal that the m-In2O3 prepared at room temperature shows higher resistance, which plays the key role in its greater sensitivity. The pore structure of material has an influence on gas adsorption on the material surface, which further affects response-recovery time of gas sen...

  11. Mesoporous In2O3: Effect of Material Structure on the Gas Sensing

    Directory of Open Access Journals (Sweden)

    Z. X. Cheng

    2011-01-01

    Full Text Available We present a semiconductor gas sensor based on mesoporous In2O3 (m-In2O3. The m-In2O3 was successfully fabricated by a simple sol-gel process, using block copolymer PE6800 as a soft template. The results of gas sensing reveal that the m-In2O3 prepared at room temperature shows higher resistance, which plays the key role in its greater sensitivity. The pore structure of material has an influence on gas adsorption on the material surface, which further affects response-recovery time of gas sensor.

  12. Multi-tiered sensing and data processing for monitoring ship structures

    Energy Technology Data Exchange (ETDEWEB)

    Farrar, Charles [Los Alamos National Laboratory; Salvino, Liming [NSWCCD; Lynch, Jerome [UNIV. OF MICHIGAN; Brady, Thomas [NSWCCD

    2009-01-01

    A comprehensive structural health monitoring (SHM) system is a critical mechanism to ensure hull integrity and evaluate structural performance over the life of a ship, especially for lightweight high-speed ships. One of the most important functions of a SHM system is to provide real-time performance guidance and reduce the risk of structural damage during operations at sea. This is done by continuous feedback from onboard sensors providing measurements of seaway loads and structural responses. Applications of SHM should also include diagnostic capabilities such as identifying the presence of damage, assessing the location and extent of damage when it does occur in order to plan for future inspection and maintenance. The development of such SHM systems is extremely challenging because of the physical size of these structures, the widely varying and often extreme operational and environmental conditions associated with the missions of high performance ships, the lack of data from known damage conditions, the limited sensing that was not designed specifically for SHM, the management of the vast amounts of data, and the need for continued, real-time data processing. This paper will discuss some of these challenges and several outstanding issues that need to be addressed in the context of applying various SHM approaches to sea trials data measured on an aluminum high-speed catamaran, the HSV-2 Swift. A multi-tiered approach for sensing and data processing will be discussed as potential SHM architecture for future shipboard application. This approach will involve application of low cost and dense sensor arrays such as wireless communications in selected areas of the ship hull in addition to conventional sensors measuring global structural response of the ship. A recent wireless hull monitoring demo on FSF-I SeaFighter will be discussed as an example to show how this proposed architecture is a viable approach for long-term and real-time hull monitoring.

  13. Insight toward epithelial Na+ channel mechanism revealed by the acid-sensing ion channel 1 structure.

    Science.gov (United States)

    Stockand, James D; Staruschenko, Alexander; Pochynyuk, Oleh; Booth, Rachell E; Silverthorn, Dee U

    2008-09-01

    The epithelial Na(+) channel/degenerin (ENaC/DEG) protein family includes a diverse group of ion channels, including nonvoltage-gated Na(+) channels of epithelia and neurons, and the acid-sensing ion channel 1 (ASIC1). In mammalian epithelia, ENaC helps regulate Na(+) and associated water transport, making it a critical determinant of systemic blood pressure and pulmonary mucosal fluidity. In the nervous system, ENaC/DEG proteins are related to sensory transduction. While the importance and physiological function of these ion channels are established, less is known about their structure. One hallmark of the ENaC/DEG channel family is that each channel subunit has only two transmembrane domains connected by an exceedingly large extracellular loop. This subunit structure was recently confirmed when Jasti and colleagues determined the crystal structure of chicken ASIC1, a neuronal acid-sensing ENaC/DEG channel. By mapping ENaC to the structural coordinates of cASIC1, as we do here, we hope to provide insight toward ENaC structure. ENaC, like ASIC1, appears to be a trimeric channel containing 1alpha, 1beta, and 1gamma subunit. Heterotrimeric ENaC and monomeric ENaC subunits within the trimer possibly contain many of the major secondary, tertiary, and quaternary features identified in cASIC1 with a few subtle but critical differences. These differences are expected to have profound effects on channel behavior. In particular, they may contribute to ENaC insensitivity to acid and to its constitutive activity in the absence of time- and ligand-dependent inactivation. Experiments resulting from this comparison of cASIC1 and ENaC may help clarify unresolved issues related to ENaC architecture, and may help identify secondary structures and residues critical to ENaC function.

  14. Bond slip detection of concrete-encased composite structure using shear wave based active sensing approach

    Science.gov (United States)

    Zeng, Lei; Parvasi, Seyed Mohammad; Kong, Qingzhao; Huo, Linsheng; Lim, Ing; Li, Mo; Song, Gangbing

    2015-12-01

    Concrete-encased composite structure exhibits improved strength, ductility and fire resistance compared to traditional reinforced concrete, by incorporating the advantages of both steel and concrete materials. A major drawback of this type of structure is the bond slip introduced between steel and concrete, which directly reduces the load capacity of the structure. In this paper, an active sensing approach using shear waves to provide monitoring and early warning of the development of bond slip in the concrete-encased composite structure is proposed. A specimen of concrete-encased composite structure was investigated. In this active sensing approach, shear mode smart aggregates (SAs) embedded in the concrete act as actuators and generate desired shear stress waves. Distributed piezoceramic transducers installed in the cavities of steel plates act as sensors and detect the wave response from shear mode SAs. Bond slip acts as a form of stress relief and attenuates the wave propagation energy. Experimental results from the time domain analysis clearly indicate that the amplitudes of received signal by lead zirconate titanate sensors decreased when bond slip occurred. In addition, a wavelet packet-based analysis was developed to compute the received signal energy values, which can be used to determine the initiation and development of bond slip in concrete-encased composite structure. In order to establish the validity of the proposed method, a 3D finite element analysis of the concrete-steel bond model is further performed with the aid of the commercial finite element package, Abaqus, and the numerical results are compared with the results obtained in experimental study.

  15. CHANGES OF BACKSCATTERING PARAMETERS DURING CHILLING INJURY IN BANANAS

    Directory of Open Access Journals (Sweden)

    NORHASHILA HASHIM

    2014-06-01

    Full Text Available The change in backscattering parameters during the appearance of chilling injury in bananas was investigated. Bananas were stored at a chilling temperature for two days and the degrees of the chilling injuries that appeared were measured before, during and after storage using backscattering imaging and visual assessment. Laser lights at 660 nm and 785 nm wavelengths were shot consecutively onto the samples in a dark room and a camera was used to capture the backscattered lights that appeared on the samples. The captured images were analysed and the changes of intensity against pixel count were plotted into graphs. The plotted graph provides useful information of backscattering parameters such as inflection point (IP, slope after inflection point (SA, and full width at half maximum (FWHM and saturation radius (RSAT. Results of statistical analysis indicated that there were significant changes of these backscattering parameters as chilling injury developed.

  16. SOME ASPECTS OF TECHNOLOGICAL PROCESS OF CASTINGS IN COATED CHILL

    Directory of Open Access Journals (Sweden)

    A. N. Krutilin

    2010-01-01

    Full Text Available Analysis of technological process of pouring into coated iron chill is presented. It is shown that the process is very sensitive to the change of technological parameters, is rather complex in regulation and control.

  17. Advancements in sensing and perception using structured lighting techniques :an LDRD final report.

    Energy Technology Data Exchange (ETDEWEB)

    Novick, David Keith; Padilla, Denise D.; Davidson, Patrick A. Jr. (.; .); Carlson, Jeffrey J.

    2005-09-01

    This report summarizes the analytical and experimental efforts for the Laboratory Directed Research and Development (LDRD) project entitled ''Advancements in Sensing and Perception using Structured Lighting Techniques''. There is an ever-increasing need for robust, autonomous ground vehicles for counterterrorism and defense missions. Although there has been nearly 30 years of government-sponsored research, it is undisputed that significant advancements in sensing and perception are necessary. We developed an innovative, advanced sensing technology for national security missions serving the Department of Energy, the Department of Defense, and other government agencies. The principal goal of this project was to develop an eye-safe, robust, low-cost, lightweight, 3D structured lighting sensor for use in broad daylight outdoor applications. The market for this technology is wide open due to the unavailability of such a sensor. Currently available laser scanners are slow, bulky and heavy, expensive, fragile, short-range, sensitive to vibration (highly problematic for moving platforms), and unreliable for outdoor use in bright sunlight conditions. Eye-safety issues are a primary concern for currently available laser-based sensors. Passive, stereo-imaging sensors are available for 3D sensing but suffer from several limitations : computationally intensive, require a lighted environment (natural or man-made light source), and don't work for many scenes or regions lacking texture or with ambiguous texture. Our approach leveraged from the advanced capabilities of modern CCD camera technology and Center 6600's expertise in 3D world modeling, mapping, and analysis, using structured lighting. We have a diverse customer base for indoor mapping applications and this research extends our current technology's lifecycle and opens a new market base for outdoor 3D mapping. Applications include precision mapping, autonomous navigation, dexterous

  18. Remote Sensing-Based Characterization of Settlement Structures for Assessing Local Potential of District Heat

    Directory of Open Access Journals (Sweden)

    Michael Nast

    2011-07-01

    Full Text Available In Europe, heating of houses and commercial areas is one of the major contributors to greenhouse gas emissions. When considering the drastic impact of an increasing emission of greenhouse gases as well as the finiteness of fossil resources, the usage of efficient and renewable energy generation technologies has to be increased. In this context, small-scale heating networks are an important technical component, which enable the efficient and sustainable usage of various heat generation technologies. This paper investigates how the potential of district heating for different settlement structures can be assessed. In particular, we analyze in which way remote sensing and GIS data can assist the planning of optimized heat allocation systems. In order to identify the best suited locations, a spatial model is defined to assess the potential for small district heating networks. Within the spatial model, the local heat demand and the economic costs of the necessary heat allocation infrastructure are compared. Therefore, a first and major step is the detailed characterization of the settlement structure by means of remote sensing data. The method is developed on the basis of a test area in the town of Oberhaching in the South of Germany. The results are validated through detailed in situ data sets and demonstrate that the model facilitates both the calculation of the required input parameters and an accurate assessment of the district heating potential. The described method can be transferred to other investigation areas with a larger spatial extent. The study underlines the range of applications for remote sensing-based analyses with respect to energy-related planning issues.

  19. Five 8-hydroxyquinolinate-based coordination polymers with tunable structures and photoluminescent properties for sensing nitroaromatics.

    Science.gov (United States)

    Zhang, Liyan; Sun, Liying; Li, Xinyuan; Tian, Yulan; Yuan, Guozan

    2015-01-01

    Using two 8-hydroxyquinolinate ligands (L1-MOM and L2-MOM) containing 3-pyridyl or 4-pyridyl groups, five novel coordination polymers, namely, [Zn3(L1)6] (1), [Zn(L1)2]·2MeOH (2), [Zn(L2)2] (3), [Cd(L2)2] (4), and [Cd4(L1)6]·13H2O (5), were synthesized and characterized by a variety of techniques. Single-crystal X-ray structures have revealed that these coordination polymers exhibit a structural diversification due to the different choices of metal salts and the effect of pyridyl nitrogen position. Compounds 1-5 exhibited different fluorescence emissions and lifetimes upon excitation in the solid state. The sensing behavior of these polymers was also investigated upon exposure to vapors of various nitroaromatic molecules (analytes). The results show that all five polymers are capable of sensing these nitroaromatic molecules in the vapor phase through fluorescence quenching. Interestingly, 3 exhibits superior sensitivity to the analytes in comparison with other polymers. 2-Nitrotoluene quenches the emission of 3 by as much as 96%.

  20. Multi-source energy harvester to power sensing hardware on rotating structures

    Energy Technology Data Exchange (ETDEWEB)

    Schlichting, Alezander D [Los Alamos National Laboratory; Ouellette, Scott [Los Alamos National Laboratory; Carlson, Clinton P [Los Alamos National Laboratory; Farinholt, Kevin M [Los Alamos National Laboratory; Park, Gyuhae [Los Alamos National Laboratory; Farrar, Charles [Los Alamos National Laboratory

    2010-01-01

    The U.S. Department of Energy (DOE) proposes to meet 20% of the nation's energy needs through wind power by the year 2030. To accomplish this goal, the industry will need to produce larger (> 100m diameter) turbines to increase efficiency and maximize energy production. It will be imperative to instrument the large composite structures with onboard sensing to provide structural health monitoring capabilities to understand the global response and integrity of these systems as they age. A critical component in the deployment of such a system will be a robust power source that can operate for the lifespan of the wind turbine. In this paper we consider the use of discrete, localized power sources that derive energy from the ambient (solar, thermal) or operational (kinetic) environment. This approach will rely on a multi-source configuration that scavenges energy from photovoltaic and piezoelectric transducers. Each harvester is first characterized individually in the laboratory and then they are combined through a multi-source power conditioner that is designed to combine the output of each harvester in series to power a small wireless sensor node that has active-sensing capabilities. The advantages/disadvantages of each approach are discussed, along with the proposed design for a field ready energy harvester that will be deployed on a small-scale 19.8m diameter wind turbine.

  1. Quorum Sensing Inhibition and Structure-Activity Relationships of β-Keto Esters.

    Science.gov (United States)

    Forschner-Dancause, Stephanie; Poulin, Emily; Meschwitz, Susan

    2016-01-01

    Traditional therapeutics to treat bacterial infections have given rise to multi-drug resistant pathogens, which pose a major threat to human and animal health. In several pathogens, quorum sensing (QS)-a cell-cell communication system in bacteria-controls the expression of genes responsible for pathogenesis, thus representing a novel target in the fight against bacterial infections. Based on the structure of the autoinducers responsible for QS activity and other QS inhibitors, we hypothesize that β-keto esters with aryl functionality could possess anti-QS activity. A panel of nineteen β-keto ester analogs was tested for the inhibition of bioluminescence (a QS-controlled phenotype) in the marine pathogen Vibrio harveyi. Initial screening demonstrated the need of a phenyl ring at the C-3 position for antagonistic activity. Further additions to the phenyl ring with 4-substituted halo groups or a 3- or 4-substituted methoxy group resulted in the most active compounds with IC50 values ranging from 23 µM to 53 µM. The compounds additionally inhibit green fluorescent protein production by E. coli JB525. Evidence is presented that aryl β-keto esters may act as antagonists of bacterial quorum sensing by competing with N-acyl homoserine lactones for receptor binding. Expansion of the β-keto ester panel will enable us to obtain more insight into the structure-activity relationships needed to allow for the development of novel anti-virulence agents. PMID:27463706

  2. Coupling Sensing Hardware with Data Interrogation Software for Structural Health Monitoring

    Directory of Open Access Journals (Sweden)

    Charles R. Farrar

    2006-01-01

    Full Text Available The process of implementing a damage detection strategy for aerospace, civil and mechanical engineering infrastructure is referred to as structural health monitoring (SHM. The authors' approach is to address the SHM problem in the context of a statistical pattern recognition paradigm. In this paradigm, the process can be broken down into four parts: (1 Operational Evaluation, (2 Data Acquisition and Cleansing, (3 Feature Extraction and Data Compression, and (4 Statistical Model Development for Feature Discrimination. These processes must be implemented through hardware or software and, in general, some combination of these two approaches will be used. This paper will discuss each portion of the SHM process with particular emphasis on the coupling of a general purpose data interrogation software package for structural health monitoring with a modular wireless sensing and processing platform. More specifically, this paper will address the need to take an integrated hardware/software approach to developing SHM solutions.

  3. Filtered gradient compressive sensing reconstruction algorithm for sparse and structured measurement matrices

    Science.gov (United States)

    Mejia, Yuri H.; Arguello, Henry

    2016-05-01

    Compressive sensing state-of-the-art proposes random Gaussian and Bernoulli as measurement matrices. Nev- ertheless, often the design of the measurement matrix is subject to physical constraints, and therefore it is frequently not possible that the matrix follows a Gaussian or Bernoulli distribution. Examples of these lim- itations are the structured and sparse matrices of the compressive X-Ray, and compressive spectral imaging systems. A standard algorithm for recovering sparse signals consists in minimizing an objective function that includes a quadratic error term combined with a sparsity-inducing regularization term. This problem can be solved using the iterative algorithms for solving linear inverse problems. This class of methods, which can be viewed as an extension of the classical gradient algorithm, is attractive due to its simplicity. However, current algorithms are slow for getting a high quality image reconstruction because they do not exploit the structured and sparsity characteristics of the compressive measurement matrices. This paper proposes the development of a gradient-based algorithm for compressive sensing reconstruction by including a filtering step that yields improved quality using less iterations. This algorithm modifies the iterative solution such that it forces to converge to a filtered version of the residual AT y, where y is the measurement vector and A is the compressive measurement matrix. We show that the algorithm including the filtering step converges faster than the unfiltered version. We design various filters that are motivated by the structure of AT y. Extensive simulation results using various sparse and structured matrices highlight the relative performance gain over the existing iterative process.

  4. Damage detection in composite structures based on optical fibre strain sensing and finite element model updating

    Energy Technology Data Exchange (ETDEWEB)

    Nosenzo, G.; Dalton, T. [Stokes Research Inst., Univ. of Limerick, Limerick (Ireland); Whelan, M.P. [European Commission Joint Research Centre, Ispra (Italy)

    2003-07-01

    A prototype system for condition monitoring of composite structures is described that relies on the on-line measurement of dynamic strains in order to detect any deterioration in performance due to the accumulation of damage. Strain data from both long gauge and point optical fibre sensors are employed to update finite element models of the analysed structures. Together with Bragg grating point sensors, an innovative Fabry-Perot interferometric long gauge strain sensor is proposed. The cavity of these sensors consists of a pair of matched Bragg grating reflectors allowing a number of sensors of the desired length to be wavelength multiplexed on a single fibre, with the advantage of minimum intrusivity in composite materials while retaining sensing capability over the whole structure. A heterodyne based demodulation system, tailored for these sensors, has been employed. Gradient based optimisation algorithms have been utilised to update structural Finite Elements models based on the output from the fibre optic sensors and strain based modal analyses. These procedures were used to detect the location of areas with known modifications of the stiffness properties in composite structures and showed good results, as the damaged areas have been correctly located. The comparison with results obtained using more conventional updating techniques shows the validity of the dynamic strain data approach in the damage detection field. (orig.)

  5. Multi-physics damage sensing in nano-engineered structural composites.

    Science.gov (United States)

    de Villoria, Roberto Guzmán; Yamamoto, Namiko; Miravete, Antonio; Wardle, Brian L

    2011-05-01

    Non-destructive evaluation techniques can offer viable diagnostic and prognostic routes to mitigating failures in engineered structures such as bridges, buildings and vehicles. However, existing techniques have significant drawbacks, including poor spatial resolution and limited in situ capabilities. We report here a novel approach where structural advanced composites containing electrically conductive aligned carbon nanotubes (CNTs) are ohmically heated via simple electrical contacts, and damage is visualized via thermographic imaging. Damage, in the form of cracks and other discontinuities, usefully increases resistance to both electrical and thermal transport in these materials, which enables tomographic full-field damage assessment in many cases. Characteristics of the technique include the ability for real-time measurement of the damage state during loading, low-power operation (e.g. 15 °C rise at 1 W), and beyond state-of-the-art spatial resolution for sensing damage in composites. The enhanced thermographic technique is a novel and practical approach for in situ monitoring to ascertain structural health and to prevent structural failures in engineered structures such as aerospace and automotive vehicles and wind turbine blades, among others.

  6. Fracture analysis of chilled cast iron camshaft

    Institute of Scientific and Technical Information of China (English)

    Li Ping; Li Fengjun; Cai Anke; Wei Bokang

    2009-01-01

    The fracture of a camshaft made of chilled cast iron, installed in a home-made Fukang car, happened only after running over a distance of 6,200 km. The fractured camshaft was received to conduct a series of failure analyses using visual inspection, SEM observation of fracture section, microstructure analysis, chemical composition analysis and hardness examination and so on, while those of CKD camshaft made by Citroen Company in France was also simultaneously analyzed to compare the difference between them. The results showed that the fracture of the camshaft mainly results from white section in macrostructure and Ledeburite in microstructure; the crack in the fractured camshaft should be recognized to initiate at the boundary of coarser needle-like carbide and matrix, and then propagate through the transverse section. At the same time, the casting defects such as dendritic shrinkage, accumulated inclusion and initiated crack and abnormal external force might stimulate the fracture of camshaft as well. Based on failure analysis, some measures have been employed, and as a result, the fracture of home-made camshafts has been effectively prevented.

  7. Use of remotely sensed data to assess neotropical dry forest structure and diversity

    Science.gov (United States)

    Kalacska, Margaret Erika Rose

    Due to a number of socioeconomic and environmental factors the tropical dry forest has been among the most anthropogenically disturbed, least protected and understudied systems. By taking advantage of the available satellite imagery and investigating the possibility of using these data for inferring characteristics of the tropical dry forest at large scales, the main objective of this thesis is to explore the use of remote sensing to assess tropical dry forest structure and diversity. Initially, the accuracy of four global and regional forest cover assessments are compared at the national level for Costa Rica and then examined in greater detail for two tropical dry forest sites in Costa Rica and Mexico. Significant errors were found systematically throughout each data set. When these errors are examined in terms of carbon sequestration forecasted over a ten-year period, the discrepancies between the maps are valued in the millions of dollars. Second, a comprehensive calibration methodology was established for leaf area index (LAI) by using a combination of litter traps, species specific leaf area values and optical estimates of LAI. In the calibration of the ground-based optical LAI estimates, it was found that the instrument underestimated the actual LAI by 40% or more in the wet season. Next, a new method of estimating LAI from satellite imagery using Bayesian Networks was explored followed by an examination of the effects of season and successional stage on forest structure and spectral vegetation indices for three Mesoamerican dry forests. Differences among the sites are attributed to both climate and varying land use and land management practices. Finally, the structure and floristic diversity of a dry forest in Costa Rica is estimated from hyperspectral satellite imagery (Hyperion). It was found that the dry season image produced the best results using a selection of wavelet decomposition coefficient elements. The final chapter summarizes the challenges for

  8. Structural Insights into Ligand Recognition by a Sensing Domain of the Cooperative Glycine Riboswitch

    Energy Technology Data Exchange (ETDEWEB)

    L Huang; A Serganov; D Patel

    2011-12-31

    Glycine riboswitches regulate gene expression by feedback modulation in response to cooperative binding to glycine. Here, we report on crystal structures of the second glycine-sensing domain from the Vibrio cholerae riboswitch in the ligand-bound and unbound states. This domain adopts a three-helical fold that centers on a three-way junction and accommodates glycine within a bulge-containing binding pocket above the junction. Glycine recognition is facilitated by a pair of bound Mg{sup 2+} cations and governed by specific interactions and shape complementarity with the pocket. A conserved adenine extrudes from the binding pocket and intercalates into the junction implying that glycine binding in the context of the complete riboswitch could impact on gene expression by stabilizing the riboswitch junction and regulatory P1 helix. Analysis of riboswitch interactions in the crystal and footprinting experiments indicates that adjacent glycine-sensing modules of the riboswitch could form specific interdomain interactions, thereby potentially contributing to the cooperative response.

  9. COMPRESSED SPEECH SIGNAL SENSING BASED ON THE STRUCTURED BLOCK SPARSITY WITH PARTIAL KNOWLEDGE OF SUPPORT

    Institute of Scientific and Technical Information of China (English)

    Ji Yunyun; Yang Zhen; Xu Qian

    2012-01-01

    Structural and statistical characteristics of signals can improve the performance of Compressed Sensing (CS).Two kinds of features of Discrete Cosine Transform (DCT) coefficients of voiced speech signals are discussed in this paper.The first one is the block sparsity of DCT coefficients of voiced speech formulated from two different aspects which are the distribution of the DCT coefficients of voiced speech and the comparison of reconstruction performance between the mixed l2 /l1 program and Basis Pursuit (BP).The block sparsity of DCT coefficients of voiced speech means that some algorithms of block-sparse CS can be used to improve the recovery performance of speech signals.It is proved by the simulation results of the l2 / reweighted l1 mixed program which is an improved version of the mixed l2 /l1 program.The second one is the well known large DCT coefficients of voiced speech focus on low frequency.In line with this feature,a special Gaussian and Partial Identity Joint (GPIJ)matrix is constructed as the sensing matrix for voiced speech signals.Simulation results show that the GPIJ matrix outperforms the classical Gaussian matrix for speech signals of male and female adults.

  10. Structure and Oxygen Sensing Properties of TiO2 Porous Semiconductor Thin Films

    Institute of Scientific and Technical Information of China (English)

    JI Huiming; L(U) Ying; MA Shicai; LI Yan

    2007-01-01

    Semiconductor-type TiO2 oxygen sensing thin films were synthesized using tetrabutyl titanate ( Ti(OBu)4 ) as precursor and diethanolamine (DEA) as complexing agent by the sol-gel process. The porous and oxygen sensing TiO2 films were obtained by the addition of polyethylene glycol (PEG). The micrographs of scanning electron microscope (SEM) show that the pores of the sample about 400-600 nm in size with PEG(2 000 g/mol) are larger than those about 300 nm in size with PEG( 1 000 g/mol), while the density of pores is lower. The results also indicate that increasing the content of PEG properly is beneficial to the formation of porous structure. With the increasing content of PEG from 0 g to 2.5 g, the oxygen sensitivity increases from 330 to more than 1 000 at 800 ℃, from 170 to more than 1 000 at 900 ℃, and the response time to O2 and H2 are about 1.5 s and less than l s, respectively.

  11. Structural, electrical and gas-sensing properties of In2O3 : Ag composite nanoparticle layers

    Indian Academy of Sciences (India)

    B R Mehta; V N Singh

    2005-11-01

    The central objective of this study is to investigate (i) size-dependent properties of In2O3 nanoparticles and (ii) the role of metal additives in enhancing the gas sensing response. For this purpose, In2O3 : Ag composite nanoparticle layers having well-defined individual nanoparticle size and composition have been grown by a two step synthesis method. Thermogravimetric analysis, X-ray diffraction and transmission electron microscopy have been used to study the effect of post-synthesis heat treatment on the size and structure of the nanoparticles. A first-time unambiguous observation of size-dependent lowering of transformation temperature has been explained in terms of lower cohesive energy of surface atoms and increase in surface-to-volume ratio with decrease in nanoparticle size. The gas sensing studies of In2O3 as well as the In2O3 : Ag composite nanoparticle layers have been studied as a function of size and composition. In2O3 : Ag composite nanoparticle layers with 15% silver show a sensitivity of 436 and response time of 6 s for 1000 ppm of ethanol in air. Ag additives form a p-type Ag2O, which interact with n-type In2O3 to produce an electron-deficient space-charge layer. In the presence of ethanol, interfacial Ag2O reduces to Ag, creating an accumulation layer in In2O3 resulting in increased sensitivity.

  12. Structural mechanism of ligand activation in human calcium-sensing receptor

    Science.gov (United States)

    Geng, Yong; Mosyak, Lidia; Kurinov, Igor; Zuo, Hao; Sturchler, Emmanuel; Cheng, Tat Cheung; Subramanyam, Prakash; Brown, Alice P; Brennan, Sarah C; Mun, Hee-chang; Bush, Martin; Chen, Yan; Nguyen, Trang X; Cao, Baohua; Chang, Donald D; Quick, Matthias; Conigrave, Arthur D; Colecraft, Henry M; McDonald, Patricia; Fan, Qing R

    2016-01-01

    Human calcium-sensing receptor (CaSR) is a G-protein-coupled receptor (GPCR) that maintains extracellular Ca2+ homeostasis through the regulation of parathyroid hormone secretion. It functions as a disulfide-tethered homodimer composed of three main domains, the Venus Flytrap module, cysteine-rich domain, and seven-helix transmembrane region. Here, we present the crystal structures of the entire extracellular domain of CaSR in the resting and active conformations. We provide direct evidence that L-amino acids are agonists of the receptor. In the active structure, L-Trp occupies the orthosteric agonist-binding site at the interdomain cleft and is primarily responsible for inducing extracellular domain closure to initiate receptor activation. Our structures reveal multiple binding sites for Ca2+ and PO43- ions. Both ions are crucial for structural integrity of the receptor. While Ca2+ ions stabilize the active state, PO43- ions reinforce the inactive conformation. The activation mechanism of CaSR involves the formation of a novel dimer interface between subunits. DOI: http://dx.doi.org/10.7554/eLife.13662.001 PMID:27434672

  13. Enhanced recovery of subsurface geological structures using compressed sensing and the Ensemble Kalman filter

    KAUST Repository

    Sana, Furrukh

    2015-07-26

    Recovering information on subsurface geological features, such as flow channels, holds significant importance for optimizing the productivity of oil reservoirs. The flow channels exhibit high permeability in contrast to low permeability rock formations in their surroundings, enabling formulation of a sparse field recovery problem. The Ensemble Kalman filter (EnKF) is a widely used technique for the estimation of subsurface parameters, such as permeability. However, the EnKF often fails to recover and preserve the channel structures during the estimation process. Compressed Sensing (CS) has shown to significantly improve the reconstruction quality when dealing with such problems. We propose a new scheme based on CS principles to enhance the reconstruction of subsurface geological features by transforming the EnKF estimation process to a sparse domain representing diverse geological structures. Numerical experiments suggest that the proposed scheme provides an efficient mechanism to incorporate and preserve structural information in the estimation process and results in significant enhancement in the recovery of flow channel structures.

  14. Structural mechanism of ligand activation in human calcium-sensing receptor

    Energy Technology Data Exchange (ETDEWEB)

    Geng, Yong; Mosyak, Lidia; Kurinov, Igor; Zuo, Hao; Sturchler, Emmanuel; Cheng, Tat Cheung; Subramanyam, Prakash; Brown, Alice P.; Brennan, Sarah C.; Mun, Hee-chang; Bush, Martin; Chen, Yan; Nguyen, Trang X.; Cao, Baohua; Chang, Donald D.; Quick, Matthias; Conigrave, Arthur D.; Colecraft, Henry M.; McDonald, Patricia; Fan, Qing R.

    2016-07-19

    Human calcium-sensing receptor (CaSR) is a G-protein-coupled receptor (GPCR) that maintains extracellular Ca2+homeostasis through the regulation of parathyroid hormone secretion. It functions as a disulfide-tethered homodimer composed of three main domains, the Venus Flytrap module, cysteine-rich domain, and seven-helix transmembrane region. Here, we present the crystal structures of the entire extracellular domain of CaSR in the resting and active conformations. We provide direct evidence that L-amino acids are agonists of the receptor. In the active structure, L-Trp occupies the orthosteric agonist-binding site at the interdomain cleft and is primarily responsible for inducing extracellular domain closure to initiate receptor activation. Our structures reveal multiple binding sites for Ca2+and PO43-ions. Both ions are crucial for structural integrity of the receptor. While Ca2+ions stabilize the active state, PO43-ions reinforce the inactive conformation. The activation mechanism of CaSR involves the formation of a novel dimer interface between subunits.

  15. Archetypal sandwich-structured CuO for high performance non-enzymatic sensing of glucose

    Science.gov (United States)

    Meher, Sumanta Kumar; Rao, G. Ranga

    2013-02-01

    In the quest to enhance the selectivity and sensitivity of novel structured metal oxides for electrochemical non-enzymatic sensing of glucose, we report here a green synthesis of unique sandwich-structured CuO on a large scale under microwave mediated homogeneous precipitation conditions. The physicochemical studies carried out by XRD and BET methods show that the monoclinic CuO formed via thermal decomposition of Cu2(OH)2CO3 possesses monomodal channel-type pores with largely improved surface area (~43 m2 g-1) and pore volume (0.163 cm3 g-1). The fascinating surface morphology and pore structure of CuO is formulated due to homogeneous crystallization and microwave induced self assembly during synthesis. The cyclic voltammetry and chronoamperometry studies show diffusion controlled glucose oxidation at ~0.6 V (vs. Ag/AgCl) with extremely high sensitivity of 5342.8 μA mM-1 cm-2 and respective detection limit and response time of ~1 μM and ~0.7 s, under a wide dynamic concentration range of glucose. The chronoamperometry measurements demonstrate that the sensitivity of CuO to glucose is unaffected by the absence of dissolved oxygen and presence of poisoning chloride ions in the reaction medium, which essentially implies high poison resistance activity of the sandwich-structured CuO. The sandwich-structured CuO also shows insignificant interference/significant selectivity to glucose, even in the presence of high concentrations of other sugars as well as reducing species. In addition, the sandwich-structured CuO shows excellent reproducibility (relative standard deviation of ~2.4% over ten identically fabricated electrodes) and outstanding long term stability (only ~1.3% loss in sensitivity over a period of one month) during non-enzymatic electrochemical sensing of glucose. The unique microstructure and suitable channel-type pore architecture provide structural stability and maximum accessible electroactive surface for unimpeded mobility of glucose as well as the

  16. Structural and electronic engineering of 3DOM WO3 by alkali metal doping for improved NO2 sensing performance

    Science.gov (United States)

    Wang, Zhihua; Fan, Xiaoxiao; Han, Dongmei; Gu, Fubo

    2016-05-01

    Novel alkali metal doped 3DOM WO3 materials were prepared using a simple colloidal crystal template method. Raman, XRD, SEM, TEM, XPS, PL, Hall and UV-Vis techniques were used to characterize the structural and electronic properties of all the products, while the corresponding sensing performances targeting ppb level NO2 were determined at different working temperatures. For the overall goal of structural and electronic engineering, the co-effect of structural and electronic properties on the improved NO2 sensing performance of alkali metal doped 3DOM WO3 was studied. The test results showed that the gas sensing properties of 3DOM WO3/Li improved the most, with the fast response-recovery time and excellent selectivity. More importantly, the response of 3DOM WO3/Li to 500 ppb NO2 was up to 55 at room temperature (25 °C). The especially high response to ppb level NO2 at room temperature (25 °C) in this work has a very important practical significance. The best sensing performance of 3DOM WO3/Li could be ascribed to the most structure defects and the highest carrier mobility. And the possible gas sensing mechanism based on the model of the depletion layer was proposed to demonstrate that both structural and electronic properties are responsible for the NO2 sensing behavior.Novel alkali metal doped 3DOM WO3 materials were prepared using a simple colloidal crystal template method. Raman, XRD, SEM, TEM, XPS, PL, Hall and UV-Vis techniques were used to characterize the structural and electronic properties of all the products, while the corresponding sensing performances targeting ppb level NO2 were determined at different working temperatures. For the overall goal of structural and electronic engineering, the co-effect of structural and electronic properties on the improved NO2 sensing performance of alkali metal doped 3DOM WO3 was studied. The test results showed that the gas sensing properties of 3DOM WO3/Li improved the most, with the fast response-recovery time and

  17. Mapping multidimensional electronic structure and ultrafast dynamics with single-element detection and compressive sensing.

    Science.gov (United States)

    Spencer, Austin P; Spokoyny, Boris; Ray, Supratim; Sarvari, Fahad; Harel, Elad

    2016-01-25

    Compressive sensing allows signals to be efficiently captured by exploiting their inherent sparsity. Here we implement sparse sampling to capture the electronic structure and ultrafast dynamics of molecular systems using phase-resolved 2D coherent spectroscopy. Until now, 2D spectroscopy has been hampered by its reliance on array detectors that operate in limited spectral regions. Combining spatial encoding of the nonlinear optical response and rapid signal modulation allows retrieval of state-resolved correlation maps in a photosynthetic protein and carbocyanine dye. We report complete Hadamard reconstruction of the signals and compression factors as high as 10, in good agreement with array-detected spectra. Single-point array reconstruction by spatial encoding (SPARSE) Spectroscopy reduces acquisition times by about an order of magnitude, with further speed improvements enabled by fast scanning of a digital micromirror device. We envision unprecedented applications for coherent spectroscopy using frequency combs and super-continua in diverse spectral regions.

  18. Compressive sensing of full wave field data for structural health monitoring applications.

    Science.gov (United States)

    Di Ianni, Tommaso; De Marchi, Luca; Perelli, Alessandro; Marzani, Alessandro

    2015-07-01

    Numerous nondestructive evaluations and structural health monitoring approaches based on guide waves rely on analysis of wave fields recorded through scanning laser Doppler vibrometers (SLDVs) or ultrasonic scanners. The informative content which can be extracted from these inspections is relevant; however, the acquisition process is generally time-consuming, posing a limit in the applicability of such approaches. To reduce the acquisition time, we use a random sampling scheme based on compressive sensing (CS) to minimize the number of points at which the field is measured. The CS reconstruction performance is mostly influenced by the choice of a proper decomposition basis to exploit the sparsity of the acquired signal. Here, different bases have been tested to recover the guided waves wave field acquired on both an aluminum and a composite plate. Experimental results show that the proposed approach allows a reduction of the measurement locations required for accurate signal recovery to less than 34% of the original sampling grid.

  19. Hierarchically Structured Fullerene C70 Cube for Sensing Volatile Aromatic Solvent Vapors.

    Science.gov (United States)

    Bairi, Partha; Minami, Kosuke; Nakanishi, Waka; Hill, Jonathan P; Ariga, Katsuhiko; Shrestha, Lok Kumar

    2016-07-26

    We report the preparation of hierarchically structured fullerene C70 cubes (HFC) composed of mesoporous C70 nanorods with crystalline pore walls. Highly crystalline cubic shape C70 crystals (FC) were grown at a liquid-liquid interface formed between tert-butyl alcohol and C70 solution in mesitylene. HFCs were then prepared by washing with isopropanol of the FC at 25 °C. The growth directions and diameters of C70 nanorods could be controlled by varying washing conditions. HFCs perform as an excellent sensing system for vapor-phase aromatic solvents due to their easy diffusion through the mesoporous architecture and strong π-π interactions with the sp(2) carbon-rich pore walls. Moreover, HFCs offer an enhanced electrochemically active surface area resulting in an energy storage capacity 1 order of magnitude greater than pristine C70 and fullerene C70 cubes not containing mesoporous nanorods. PMID:27341124

  20. A TIR-NBS protein encoded by Arabidopsis Chilling Sensitive 1 (CHS1) limits chloroplast damage and cell death at low temperature.

    Science.gov (United States)

    Zbierzak, Anna Maria; Porfirova, Svetlana; Griebel, Thomas; Melzer, Michael; Parker, Jane E; Dörmann, Peter

    2013-08-01

    Survival of plants at low temperature depends on mechanisms for limiting physiological damage and maintaining growth. We mapped the chs1-1 (chilling sensitive1-1) mutation in Arabidopsis accession Columbia to the TIR-NBS gene At1g17610. In chs1-1, a single amino acid exchange at the CHS1 N-terminus close to the conserved TIR domain creates a stable mutant protein that fails to protect leaves against chilling stress. The sequence of another TIR-NBS gene (At5g40090) named CHL1 (CHS1-like 1) is related to that of CHS1. Over-expression of CHS1 or CHL1 alleviates chilling damage and enhances plant growth at moderate (24°C) and chilling (13°C) temperatures, suggesting a role for both proteins in growth homeostasis. chs1-1 mutants show induced salicylic acid production and defense gene expression at 13°C, indicative of autoimmunity. Genetic analysis of chs1-1 in combination with defense pathway mutants shows that chs1-1 chilling sensitivity requires the TIR-NBS-LRR and basal resistance regulators encoded by EDS1 and PAD4 but not salicylic acid. By following the timing of metabolic, physiological and chloroplast ultrastructural changes in chs1-1 leaves during chilling, we have established that alterations in photosynthetic complexes and thylakoid membrane integrity precede leaf cell death measured by ion leakage. At 24°C, the chs1-1 mutant appears normal but produces a massive necrotic response to virulent Pseudomonas syringae pv. tomato infection, although this does not affect bacterial proliferation. Our results suggest that CHS1 acts at an intersection between temperature sensing and biotic stress pathway activation to maintain plant performance over a range of conditions.

  1. Cod and rainbow trout as freeze-chilled meal elements

    DEFF Research Database (Denmark)

    Jensen, Louise Helene Søgaard; Nielsen, Jette; Jørgensen, Bo;

    2010-01-01

    Meal elements' are elements of a meal, e.g. portions of pre-fried meat, sauces, frozen fish or pre-processed vegetables typically prepared industrially. The meal elements are distributed to professional satellite kitchens, where the staff can combine them into complete meals. Freeze-chilling is a......Meal elements' are elements of a meal, e.g. portions of pre-fried meat, sauces, frozen fish or pre-processed vegetables typically prepared industrially. The meal elements are distributed to professional satellite kitchens, where the staff can combine them into complete meals. Freeze......-chilling is a process consisting of freezing and frozen storage followed by thawing and chilled storage. Combining the two would enable the manufacturer to produce large quantities of frozen meal elements to be released into the chill chain according to demand. We have studied the influence of freeze...... and cod and rainbow trout seem potential candidates for freeze-chilled meal elements. (C) 2009 Society of Chemical Industry...

  2. Structure, Regulation, and Inhibition of the Quorum-Sensing Signal Integrator LuxO.

    Science.gov (United States)

    Boyaci, Hande; Shah, Tayyab; Hurley, Amanda; Kokona, Bashkim; Li, Zhijie; Ventocilla, Christian; Jeffrey, Philip D; Semmelhack, Martin F; Fairman, Robert; Bassler, Bonnie L; Hughson, Frederick M

    2016-05-01

    In a process called quorum sensing, bacteria communicate with chemical signal molecules called autoinducers to control collective behaviors. In pathogenic vibrios, including Vibrio cholerae, the accumulation of autoinducers triggers repression of genes responsible for virulence factor production and biofilm formation. The vibrio autoinducer molecules bind to transmembrane receptors of the two-component histidine sensor kinase family. Autoinducer binding inactivates the receptors' kinase activities, leading to dephosphorylation and inhibition of the downstream response regulator LuxO. Here, we report the X-ray structure of LuxO in its unphosphorylated, autoinhibited state. Our structure reveals that LuxO, a bacterial enhancer-binding protein of the AAA+ ATPase superfamily, is inhibited by an unprecedented mechanism in which a linker that connects the catalytic and regulatory receiver domains occupies the ATPase active site. The conformational change that accompanies receiver domain phosphorylation likely disrupts this interaction, providing a mechanistic rationale for LuxO activation. We also determined the crystal structure of the LuxO catalytic domain bound to a broad-spectrum inhibitor. The inhibitor binds in the ATPase active site and recapitulates elements of the natural regulatory mechanism. Remarkably, a single inhibitor molecule may be capable of inhibiting an entire LuxO oligomer. PMID:27219477

  3. Use of nondestructive inspection and fiber optic sensing for damage characterization in carbon fiber fuselage structure

    Science.gov (United States)

    Neidigk, Stephen; Le, Jacqui; Roach, Dennis; Duvall, Randy; Rice, Tom

    2014-04-01

    To investigate a variety of nondestructive inspection technologies and assess impact damage characteristics in carbon fiber aircraft structure, the FAA Airworthiness Assurance Center, operated by Sandia National Labs, fabricated and impact tested two full-scale composite fuselage sections. The panels are representative of structure seen on advanced composite transport category aircraft and measured approximately 56"x76". The structural components consisted of a 16 ply skin, co-cured hat-section stringers, fastened shear ties and frames. The material used to fabricate the panels was T800 unidirectional pre-preg (BMS 8-276) and was processed in an autoclave. Simulated hail impact testing was conducted on the panels using a high velocity gas gun with 2.4" diameter ice balls in collaboration with the University of California San Diego (UCSD). Damage was mapped onto the surface of the panels using conventional, hand deployed ultrasonic inspection techniques, as well as more advanced ultrasonic and resonance scanning techniques. In addition to the simulated hail impact testing performed on the panels, 2" diameter steel tip impacts were used to produce representative impact damage which can occur during ground maintenance operations. The extent of impact damage ranges from less than 1 in2 to 55 in2 of interply delamination in the 16 ply skin. Substructure damage on the panels includes shear tie cracking and stringer flange disbonding. It was demonstrated that the fiber optic distributed strain sensing system is capable of detecting impact damage when bonded to the backside of the fuselage.

  4. Room Temperature Ammonia Gas Sensing Using Mixed Conductor based TEMPOS Structures

    Directory of Open Access Journals (Sweden)

    Amita Chandra

    2008-10-01

    Full Text Available The current/voltage characteristics of mixed (ion+electron conductor-based ‘TEMPOS’ (Tunable Electronic Material with Pores in Oxide on Silicon structures are reported. TEMPOS are novel electronic MOS-like structures having etched swift heavy ion tracks (i.e., nanopores in the dielectric layer filled with some conducting material. The three contacts (two on top and one on the bottom, which resemble the classical bipolar or field effect transistor arrangements are, in principle, interchangeable when the overall electrical resistance along the tracks and on the surface are similar. Consequently, three configurations are obtained by interchanging the top contacts with the base contact in electronic circuits. The current/voltage characteristics show a diode like behaviour. Impedance measurements have been made for TEMPOS structures with tracks filled with ion conductors and also mixed conductors to study the ammonia sensing behaviour. The impedance has been found to be a function of frequency and magnitude of the applied signal and concentration of the ammonia solution. This is attributed to the large number of charge carriers (here protons available for conduction on exposure to ammonia and also to the large surface to volume ratio of the polymer composites embedded in the ion tracks. The measurement of both, the real and imaginary parts of impedance allows one to enhance the detection sensitivity greatly.

  5. Investigation on strain sensing properties of carbon-based nanocomposites for structural aircraft applications

    Science.gov (United States)

    Lamberti, Patrizia; Spinelli, Giovanni; Tucci, Vincenzo; Guadagno, Liberata; Vertuccio, Luigi; Russo, Salvatore

    2016-05-01

    The mechanical and electrical properties of a thermosetting epoxy resin particularly indicated for the realization of structural aeronautic components and reinforced with multiwalled carbon nanotubes (MWCNTs, at 0.3 wt%) are investigated for specimens subjected to cycles and different levels of applied strain (i.e. ɛ) loaded both in axial tension and flexural mode. It is found that the piezoresistive behavior of the resulting nanocomposite evaluated in terms of variation of the electrical resistance is strongly affected by the applied mechanical stress mainly due to the high sensibility and consequent rearrangement of the electrical percolating network formed by MWCNTs in the composite at rest or even under a small strain. In fact, the variations in electrical resistance that occur during the mechanical stress are correlated to the deformation exhibited by the nanocomposites. In particular, the overall response of electrical resistance of the composite is characterized by a linear increase with the strain at least in the region of elastic deformation of the material in which the gauge factor (i.e. G.F.) of the sensor is usually evaluated. Therefore, the present study aims at investigating the possible use of the nanotechnology for application of embedded sensor systems in composite structures thus having capability of self-sensing and of responding to the surrounding environmental changes, which are some fundamental requirements especially for structural aircraft monitoring applications.

  6. Wireless Displacement Sensing Enabled by Metamaterial Probes for Remote Structural Health Monitoring

    Directory of Open Access Journals (Sweden)

    Burak Ozbey

    2014-01-01

    Full Text Available We propose and demonstrate a wireless, passive, metamaterial-based sensor that allows for remotely monitoring submicron displacements over millimeter ranges. The sensor comprises a probe made of multiple nested split ring resonators (NSRRs in a double-comb architecture coupled to an external antenna in its near-field. In operation, the sensor detects displacement of a structure onto which the NSRR probe is attached by telemetrically tracking the shift in its local frequency peaks. Owing to the NSRR’s near-field excitation response, which is highly sensitive to the displaced comb-teeth over a wide separation, the wireless sensing system exhibits a relatively high resolution (<1 µm and a large dynamic range (over 7 mm, along with high levels of linearity (R2 > 0.99 over 5 mm and sensitivity (>12.7 MHz/mm in the 1–3 mm range. The sensor is also shown to be working in the linear region in a scenario where it is attached to a standard structural reinforcing bar. Because of its wireless and passive nature, together with its low cost, the proposed system enabled by the metamaterial probes holds a great promise for applications in remote structural health monitoring.

  7. Structure, Regulation, and Inhibition of the Quorum-Sensing Signal Integrator LuxO.

    Science.gov (United States)

    Boyaci, Hande; Shah, Tayyab; Hurley, Amanda; Kokona, Bashkim; Li, Zhijie; Ventocilla, Christian; Jeffrey, Philip D; Semmelhack, Martin F; Fairman, Robert; Bassler, Bonnie L; Hughson, Frederick M

    2016-05-01

    In a process called quorum sensing, bacteria communicate with chemical signal molecules called autoinducers to control collective behaviors. In pathogenic vibrios, including Vibrio cholerae, the accumulation of autoinducers triggers repression of genes responsible for virulence factor production and biofilm formation. The vibrio autoinducer molecules bind to transmembrane receptors of the two-component histidine sensor kinase family. Autoinducer binding inactivates the receptors' kinase activities, leading to dephosphorylation and inhibition of the downstream response regulator LuxO. Here, we report the X-ray structure of LuxO in its unphosphorylated, autoinhibited state. Our structure reveals that LuxO, a bacterial enhancer-binding protein of the AAA+ ATPase superfamily, is inhibited by an unprecedented mechanism in which a linker that connects the catalytic and regulatory receiver domains occupies the ATPase active site. The conformational change that accompanies receiver domain phosphorylation likely disrupts this interaction, providing a mechanistic rationale for LuxO activation. We also determined the crystal structure of the LuxO catalytic domain bound to a broad-spectrum inhibitor. The inhibitor binds in the ATPase active site and recapitulates elements of the natural regulatory mechanism. Remarkably, a single inhibitor molecule may be capable of inhibiting an entire LuxO oligomer.

  8. Structure, Regulation, and Inhibition of the Quorum-Sensing Signal Integrator LuxO.

    Directory of Open Access Journals (Sweden)

    Hande Boyaci

    2016-05-01

    Full Text Available In a process called quorum sensing, bacteria communicate with chemical signal molecules called autoinducers to control collective behaviors. In pathogenic vibrios, including Vibrio cholerae, the accumulation of autoinducers triggers repression of genes responsible for virulence factor production and biofilm formation. The vibrio autoinducer molecules bind to transmembrane receptors of the two-component histidine sensor kinase family. Autoinducer binding inactivates the receptors' kinase activities, leading to dephosphorylation and inhibition of the downstream response regulator LuxO. Here, we report the X-ray structure of LuxO in its unphosphorylated, autoinhibited state. Our structure reveals that LuxO, a bacterial enhancer-binding protein of the AAA+ ATPase superfamily, is inhibited by an unprecedented mechanism in which a linker that connects the catalytic and regulatory receiver domains occupies the ATPase active site. The conformational change that accompanies receiver domain phosphorylation likely disrupts this interaction, providing a mechanistic rationale for LuxO activation. We also determined the crystal structure of the LuxO catalytic domain bound to a broad-spectrum inhibitor. The inhibitor binds in the ATPase active site and recapitulates elements of the natural regulatory mechanism. Remarkably, a single inhibitor molecule may be capable of inhibiting an entire LuxO oligomer.

  9. Biomass estimation as a function of vertical forest structure and forest height: potential and limitations for radar remote sensing

    OpenAIRE

    Torano Caicoya, Astor; Kugler, Florian; Papathanassiou, Kostas; Biber, Peter; Pretzsch, Hans

    2010-01-01

    One common method to estimate biomass is measuring forest height and applying allometric equations to get forest biomass. Conditions like changing forest density or changing forest structure bias the allometric relations or biomass estimation fails completely. Remote sensing systems like SAR or LIDAR allow to measure vertical structure of forests. In this paper it is investigated whether vertical structure is sensitive to biomass. For this purpose vertical biomass profiles were calculated usi...

  10. A versatile building block: the structures and functions of negative-sense single-stranded RNA virus nucleocapsid proteins

    OpenAIRE

    Sun, Yuna; Guo, Yu; Lou, Zhiyong

    2012-01-01

    Nucleocapsid protein (NPs) of negative-sense single-stranded RNA (-ssRNA) viruses function in different stages of viral replication, transcription, and maturation. Structural investigations show that -ssRNA viruses that encode NPs preliminarily serve as structural building blocks that encapsidate and protect the viral genomic RNA and mediate the interaction between genomic RNA and RNA-dependent RNA polymerase. However, recent structural results have revealed other biological functions of -ssR...

  11. Putative paternal factors controlling chilling tolerance in Korean market-type cucumber (Cucumis sativus L.)

    Science.gov (United States)

    Chilling temperatures (Korean market-type cucumber (Cucumis sativus L.) plants during winter and early spring growing seasons. Inheritance to chilling in U.S. processing cucumber is controlled by cytoplasmic (maternally) and nuclear factors. To understand inherit...

  12. Coupling of physiological and proteomic analysis to understand the ethylene- and chilling-induced kiwifruit ripening syndrome

    Directory of Open Access Journals (Sweden)

    Ioannis S Minas

    2016-02-01

    Full Text Available Kiwifruit (Actinidia deliciosa (A. Chev. C.F. Liang et A.R. Ferguson, cv. ‘Hayward’ is classified as climacteric fruit and the initiation of endogenous ethylene production following harvest is induced by exogenous ethylene or chilling exposure. To understand the biological basis of this ‘dilemma’, kiwifruit ripening responses were characterized at 20 oC following treatments with exogenous ethylene (100 μL L-1, 20 oC, 24 h or/and chilling temperature (0 oC, 10 d. All treatments elicited kiwifruit ripening and induced softening and endogenous ethylene biosynthesis, as determined by 1-aminocyclopropane-1-carboxylic acid (ACC content and ACC synthase (ACS and ACC oxidase (ACO enzyme activities after 10 d of ripening at 20 oC. Comparative proteomic analysis using two-dimensional gel electrophoresis (2DE-PAGE and nanoscale liquid chromatography coupled to tandem mass spectrometry (nanoLC-MS/MS revealed 81 kiwifruit proteins associated with ripening. Thirty-one kiwifruit proteins were identified as commonly regulated by the three treatments accompanied by dynamic changes of 10 proteins specific to exogenous ethylene, 2 to chilling treatment and 12 to their combination. Ethylene and/or chilling-responsive proteins were mainly involved in disease/defense, energy, protein destination/storage and cell structure/cell wall. Interactions between the identified proteins were demonstrated by bioinformatics analysis, allowing a more complete insight into biological pathways and molecular functions affected by ripening. The present approach provides a quantitative basis for understanding the ethylene- and chilling-induced kiwifruit ripening and climacteric fruit ripening in general.

  13. Identification of chilling and heat requirements of cherry trees—a statistical approach

    Science.gov (United States)

    Luedeling, Eike; Kunz, Achim; Blanke, Michael M.

    2013-09-01

    Most trees from temperate climates require the accumulation of winter chill and subsequent heat during their dormant phase to resume growth and initiate flowering in the following spring. Global warming could reduce chill and hence hamper the cultivation of high-chill species such as cherries. Yet determining chilling and heat requirements requires large-scale controlled-forcing experiments, and estimates are thus often unavailable. Where long-term phenology datasets exist, partial least squares (PLS) regression can be used as an alternative, to determine climatic requirements statistically. Bloom dates of cherry cv. `Schneiders späte Knorpelkirsche' trees in Klein-Altendorf, Germany, from 24 growing seasons were correlated with 11-day running means of daily mean temperature. Based on the output of the PLS regression, five candidate chilling periods ranging in length from 17 to 102 days, and one forcing phase of 66 days were delineated. Among three common chill models used to quantify chill, the Dynamic Model showed the lowest variation in chill, indicating that it may be more accurate than the Utah and Chilling Hours Models. Based on the longest candidate chilling phase with the earliest starting date, cv. `Schneiders späte Knorpelkirsche' cherries at Bonn exhibited a chilling requirement of 68.6 ± 5.7 chill portions (or 1,375 ± 178 chilling hours or 1,410 ± 238 Utah chill units) and a heat requirement of 3,473 ± 1,236 growing degree hours. Closer investigation of the distinct chilling phases detected by PLS regression could contribute to our understanding of dormancy processes and thus help fruit and nut growers identify suitable tree cultivars for a future in which static climatic conditions can no longer be assumed. All procedures used in this study were bundled in an R package (`chillR') and are provided as Supplementary materials. The procedure was also applied to leaf emergence dates of walnut (cv. `Payne') at Davis, California.

  14. The seeds of Lotus japonicus lines transformed with sense, antisense, and sense/antisense galactomannan galactosyltransferase constructs have structurally altered galactomannans in their endosperm cell walls.

    Science.gov (United States)

    Edwards, Mary E; Choo, Tze-Siang; Dickson, Cathryn A; Scott, Catherine; Gidley, Michael J; Reid, J S Grant

    2004-03-01

    Galactomannan biosynthesis in legume seed endosperms involves two Golgi membrane-bound glycosyltransferases, mannan synthase and galactomannan galactosyltransferase (GMGT). GMGT specificity is an important factor regulating the distribution and amount of (1-->6)-alpha-galactose (Gal) substitution of the (1-->4)-beta-linked mannan backbone. The model legume Lotus japonicus is shown now to have endospermic seeds with endosperm cell walls that contain a high-Gal galactomannan (mannose [Man]/Gal = 1.2-1.3). Galactomannan biosynthesis in developing L. japonicus endosperms has been mapped, and a cDNA encoding a functional GMGT has been obtained from L. japonicus endosperms during galactomannan deposition. L. japonicus has been transformed with sense, antisense, and sense/antisense ("hairpin loop") constructs of the GMGT cDNA. Some of the sense, antisense, and sense/antisense transgenic lines exhibited galactomannans with altered (higher) Man/Gal values in their (T(1) generation) seeds, at frequencies that were consistent with posttranscriptional silencing of GMGT. For T(1) generation individuals, transgene inheritance was correlated with galactomannan composition and amount in the endosperm. All the azygous individuals had unchanged galactomannans, whereas those that had inherited a GMGT transgene exhibited a range of Man/Gal values, up to about 6 in some lines. For Man/Gal values up to 4, the results were consistent with lowered Gal substitution of a constant amount of mannan backbone. Further lowering of Gal substitution was accompanied by a slight decrease in the amount of mannan backbone. Microsomal membranes prepared from the developing T(2) generation endosperms of transgenic lines showed reduced GMGT activity relative to mannan synthase. The results demonstrate structural modification of a plant cell wall polysaccharide by designed regulation of a Golgi-bound glycosyltransferase.

  15. Amelioration of Chilling Injuries in Watermelon Seedlings by Abscisic Acid

    OpenAIRE

    Korkmaz, Ahmet

    2002-01-01

    A greenhouse study, designed in a randomized complete block design with five replications, was carried out at Clemson University, Clemson, SC, USA, in the spring of 1997. The objective of the study was to investigate whether abscisic acid (ABA) would mitigate chilling damages in the watermelon, a chilling-sensitive plant. 'Crimson Sweet' [Citrullus lanatus (Thumb) Matsum. & Nakai.] watermelon seedlings were grown in a greenhouse with a temperature regime of 25ºC (day) and 20ºC...

  16. Structural analysis and thermal remote sensing of the Los Humeros Volcanic Complex: Implications for volcano structure and geothermal exploration

    Science.gov (United States)

    Norini, G.; Groppelli, G.; Sulpizio, R.; Carrasco-Núñez, G.; Dávila-Harris, P.; Pellicioli, C.; Zucca, F.; De Franco, R.

    2015-08-01

    The Los Humeros Volcanic Complex (LHVC) is an important geothermal target in the Trans-Mexican Volcanic Belt. Understanding the structure of the LHVC and its influence on the occurrence of thermal anomalies and hydrothermal fluids is important to get insights into the interplay between the volcano-tectonic setting and the characteristics of the geothermal resources in the area. In this study, we present a structural analysis of the LHVC, focused on Quaternary tectonic and volcano-tectonic features, including the areal distribution of monogenetic volcanic centers. Morphostructural analysis and structural field mapping revealed the geometry, kinematics and dynamics of the structural features in the study area. Also, thermal infrared remote sensing analysis has been applied to the LHVC for the first time, to map the main endogenous thermal anomalies. These data are integrated with newly proposed Unconformity Bounded Stratigraphic Units, to evaluate the implications for the structural behavior of the caldera complex and geothermal field. The LHVC is characterized by a multistage formation, with at least two major episodes of caldera collapse: Los Humeros Caldera (460 ka) and Los Potreros Caldera (100 ka). The study suggests that the geometry of the first collapse recalls a trap-door structure and impinges on a thick volcanic succession (10.5-1.55 Ma), now hosting the geothermal reservoir. The main ring-faults of the two calderas are buried and sealed by the widespread post-calderas volcanic products, and for this reason they probably do not have enough permeability to be the main conveyers of the hydrothermal fluid circulation. An active, previously unrecognized fault system of volcano-tectonic origin has been identified inside the Los Potreros Caldera. This fault system is the main geothermal target, probably originated by active resurgence of the caldera floor. The active fault system defines three distinct structural sectors in the caldera floor, where the

  17. Waveguide-coupled surface plasmon resonance sensor structures: Fano lineshape engineering for ultrahigh-resolution sensing

    International Nuclear Information System (INIS)

    We analyze in detail the plasmon-induced transparency and Fano resonance exhibited by a waveguide-coupled surface plasmon resonance sensor structure. It is shown that the results of electromagnetic calculations made for the structure agree very well with those of mechanical calculations made for two coupled harmonic oscillators. This implies that an analogy holds between the present electromagnetic system and the coupled-oscillator system. The analogy established allows us to conclude that the plasmon-induced transparency and Fano resonance are caused by the coupling between a surface plasmon polariton and a planar waveguide mode. Sensing action of the Fano resonance is also analyzed in detail. From the calculation of the figure of merit for the sensitivity by intensity, it is shown that there is an optimum condition for the coupling of the modes to achieve a maximum sensitivity. Under the optimum condition, the figure of merit is found to be three orders of magnitude higher than that of a conventional surface plasmon sensor. (paper)

  18. A wirelessly programmable actuation and sensing system for structural health monitoring

    Science.gov (United States)

    Long, James; Büyüköztürk, Oral

    2016-04-01

    Wireless sensor networks promise to deliver low cost, low power and massively distributed systems for structural health monitoring. A key component of these systems, particularly when sampling rates are high, is the capability to process data within the network. Although progress has been made towards this vision, it remains a difficult task to develop and program 'smart' wireless sensing applications. In this paper we present a system which allows data acquisition and computational tasks to be specified in Python, a high level programming language, and executed within the sensor network. Key features of this system include the ability to execute custom application code without firmware updates, to run multiple users' requests concurrently and to conserve power through adjustable sleep settings. Specific examples of sensor node tasks are given to demonstrate the features of this system in the context of structural health monitoring. The system comprises of individual firmware for nodes in the wireless sensor network, and a gateway server and web application through which users can remotely submit their requests.

  19. Introduction to structure from motion and its applications in remote sensing

    Energy Technology Data Exchange (ETDEWEB)

    Fair, Matt B [Los Alamos National Laboratory

    2011-01-11

    This talk discusses my experience at Los Alamos National Laboratories developing the Wide Area Persistent Surveillance (WAPS) system AngelFire and the problems with working with low resolution surface models. This experience provided a motivation to seek solutions to utilize the redundant WAPS imagery to build surface models of the urban environment. Structure from Motion (SfM) is a process that takes multiple view imagery and compute the 3D structure of a scene. We will walk through the basic algorithm and discuss areas for optimization. Military services and intelligence agencies face long-standing challenges with processing, exploiting, and disseminating ISR data. The problem is that too much data is being produced and not enough people to look at it and the problem is not going away. As a result of this data overload, we need to shift the way we think about data and find creative ways to use and present it so it can be easily digested by decision makers. SfM also provides a means for developing a data processing and organization architecture. Applications for various remote sensing applications will be discussed for motivation for why SfM and Multi-View Stereo rendering is an important area that needs to be continued to be developed.

  20. EDGE DETECTION METHOD OF REMOTE SENSING IMAGES BASED ON MATHEMATICAL MORPHOLOGY OF MULTI-STRUCTURE ELEMENTS

    Institute of Scientific and Technical Information of China (English)

    LIN Hui; DU Pei-jun; ZHAO Chang-sheng; SHU Ning

    2004-01-01

    This paper puts forward an effective,specific algorithm for edge detection.Based on multi-structure elements of gray mathematics morphology,in the light of difference between noise and edge shape of RS images,the paper establishes multi-structure elements to detect edge by utilizing the grey form transformation principle.Compared with some classical edge detection operators,such as Sobel Edge Detection Operator,LOG Edge Detection Operator,and Canny Edge Detection Operator,the experiment indicates that this new algorithm possesses very good edge detection ability,which can detect edges more effectively,but its noise-resisting ability is relatively low.Because of the bigger noise of remote sensing image,the authors probe into putting forward other edge detection method based on combination of wavelet directivity checkout technology and small-scale Mathematical Morphology finally.So,position at the edge can be accurately located,the noise can be inhibited to a certain extent and the effect of edge detection is obvious.

  1. Structural, morphological and gas sensing study of zinc doped tin oxide nanoparticles synthesized via hydrothermal technique

    Science.gov (United States)

    Singh, Davender; Kundu, Virender Singh; Maan, A. S.

    2016-07-01

    The pure and Zn-doped SnO2 nanoparticles were prepared successfully by hydrothermal route on large scale having different doping concentration of zinc from 0 to 0.20%. The calcined nanoparticles were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM) for structural and morphological studies. XRD analyses reveal that the nanoparticles of these doping concentrations are polycrystalline in nature and existed as tetragonal rutile structure, SEM study of images confirms the existence of very small, homogeneously distributed, and spherical nanoparticles. The particles size of the nanoparticles was calculated by Scherrer formula and was found in the range of 9-21 nm. The presence of dopant (i.e. zinc) and formation of Sn-O phase and hydrous nature of Zn-doped SnO2 nanoparticles are confirmed by EDX and FTIR study. The gas sensing properties of pure and Zn-doped SnO2 nanoparticles were investigated for various concentrations of methanol, ethanol and acetone at different operating temperatures and it has been found that with doping concentration of zinc (x = 0.20%) shows the maximum response 78% to methanol, 65% to ethanol and 62% to acetone respectively at different operating temperature within the measurement limit for a concentration of 100 ppm of each gases.

  2. MSV3d: database of human MisSense Variants mapped to 3D protein structure.

    Science.gov (United States)

    Luu, Tien-Dao; Rusu, Alin-Mihai; Walter, Vincent; Ripp, Raymond; Moulinier, Luc; Muller, Jean; Toursel, Thierry; Thompson, Julie D; Poch, Olivier; Nguyen, Hoan

    2012-01-01

    The elucidation of the complex relationships linking genotypic and phenotypic variations to protein structure is a major challenge in the post-genomic era. We present MSV3d (Database of human MisSense Variants mapped to 3D protein structure), a new database that contains detailed annotation of missense variants of all human proteins (20 199 proteins). The multi-level characterization includes details of the physico-chemical changes induced by amino acid modification, as well as information related to the conservation of the mutated residue and its position relative to functional features in the available or predicted 3D model. Major releases of the database are automatically generated and updated regularly in line with the dbSNP (database of Single Nucleotide Polymorphism) and SwissVar releases, by exploiting the extensive Décrypthon computational grid resources. The database (http://decrypthon.igbmc.fr/msv3d) is easily accessible through a simple web interface coupled to a powerful query engine and a standard web service. The content is completely or partially downloadable in XML or flat file formats. Database URL: http://decrypthon.igbmc.fr/msv3d.

  3. Cellular Oxygen Sensing: Crystal Structure of Hypoxia-Inducible Factor Prolyl Hydroxylase (PHD2)

    Energy Technology Data Exchange (ETDEWEB)

    McDonough,M.; Li, V.; Flashman, E.; Chowdhury, R.; Mohr, C.; Lienard, B.; Zondlo, J.; Oldham, N.; Clifton, I.; et al.

    2006-01-01

    Cellular and physiological responses to changes in dioxygen levels in metazoans are mediated via the posttranslational oxidation of hypoxia-inducible transcription factor (HIF). Hydroxylation of conserved prolyl residues in the HIF-{alpha} subunit, catalyzed by HIF prolyl-hydroxylases (PHDs), signals for its proteasomal degradation. The requirement of the PHDs for dioxygen links changes in dioxygen levels with the transcriptional regulation of the gene array that enables the cellular response to chronic hypoxia; the PHDs thus act as an oxygen-sensing component of the HIF system, and their inhibition mimics the hypoxic response. We describe crystal structures of the catalytic domain of human PHD2, an important prolyl-4-hydroxylase in the human hypoxic response in normal cells, in complex with Fe(II) and an inhibitor to 1.7 Angstroms resolution. PHD2 crystallizes as a homotrimer and contains a double-stranded {beta}-helix core fold common to the Fe(II) and 2-oxoglutarate-dependant dioxygenase family, the residues of which are well conserved in the three human PHD enzymes (PHD 1-3). The structure provides insights into the hypoxic response, helps to rationalize a clinically observed mutation leading to familial erythrocytosis, and will aid in the design of PHD selective inhibitors for the treatment of anemia and ischemic disease.

  4. Inhibition of photosynthesis by chilling in moderate light: a comparison of plants sensitive and insensitive to chilling.

    Science.gov (United States)

    Hodgson, R A; Raison, J K

    1989-12-01

    Photosynthetic activity, in leaf slices and isolated thylakoids, was examined at 25° C after preincubation of the slices at either 25° C or 4° C at a moderate photon flux density (PFD) of 450 μmol·m(-2)·s(-1), or at 4° C in the dark. The plants used wereSpinacia oleracea L.,Cucumis sativus L. andNerium oleander L. which was acclimated to growth at 20° C or 45° C. The plants were grown at a PFD of 550 μmol·m(-2)·s(-1). Photosynthesis, measured as CO2-dependent O2 evolution, was not inhibited in leaf slices from any plant after preincubation at 25° C at a moderate PFD or at 4° C in the dark. However, exposure to 4° C at a moderate PFD induced an inhibition of CO2-dependent O2 evolution within 1 h inC. sativus, a chilling-sensitive plant, and in 45° C-grownN. oleander. The inhibition in these plants after 5 h reached 80% and 40%, respectively, and was independent of the CO2 concentration but was reduced at O2 concentrations of less than 3%. Methyl-viologen-dependent O2 exchange in leaf slices from these plants was not inhibited. There was no photoxidation of chlorophyll, in isolated thylakoids, or any inhibition of electron transport at photosystem (PS)II, PSI or through both photosystems which would account for the inhibition of photosynthesis. The conditions which inhibit photosynthesis in chilling-sensitive plants do not cause inhibition inS. oleracea, a chilling-insensitive plant, or in 20° C-grownN. oleander. The CO2-dependent photosynthesis, measured at 5° C, was reduced to about 3% of that recorded at 25° C in chilling-sensitive plants but only to about 30% in the chilling-insensitive plants. Methyl-viologen-dependent O2 exchange, measured at 5° C, was greater than 25% of the activity at 25° C in all the plants. The results indicate that the mechanism of the chilling-induced inhibition of photosynthesis does not involve damage to PSII. That inhibition of photosynthesis is observed only in the chilling-sensitive plants indicates it is

  5. Sensing actin dynamics: Structural basis for G-actin-sensitive nuclear import of MAL

    Energy Technology Data Exchange (ETDEWEB)

    Hirano, Hidemi; Matsuura, Yoshiyuki, E-mail: matsuura.yoshiyuki@d.mbox.nagoya-u.ac.jp

    2011-10-22

    Highlights: {yields} MAL has a bipartite NLS that binds to Imp{alpha} in an extended conformation. {yields} Mutational analyses verified the functional significance of MAL-Imp{alpha} interactions. {yields} Induced folding and NLS-masking by G-actins inhibit nuclear import of MAL. -- Abstract: The coordination of cytoskeletal actin dynamics with gene expression reprogramming is emerging as a crucial mechanism to control diverse cellular processes, including cell migration, differentiation and neuronal circuit assembly. The actin-binding transcriptional coactivator MAL (also known as MRTF-A/MKL1/BSAC) senses G-actin concentration and transduces Rho GTPase signals to serum response factor (SRF). MAL rapidly shuttles between the cytoplasm and the nucleus in unstimulated cells but Rho-induced depletion of G-actin leads to MAL nuclear accumulation and activation of transcription of SRF:MAL-target genes. Although the molecular and structural basis of actin-regulated nucleocytoplasmic shuttling of MAL is not understood fully, it is proposed that nuclear import of MAL is mediated by importin {alpha}/{beta} heterodimer, and that G-actin competes with importin {alpha}/{beta} for the binding to MAL. Here we present structural, biochemical and cell biological evidence that MAL has a classical bipartite nuclear localization signal (NLS) in the N-terminal 'RPEL' domain containing Arg-Pro-X-X-X-Glu-Leu (RPEL) motifs. The NLS residues of MAL adopt an extended conformation and bind along the surface groove of importin-{alpha}, interacting with the major- and minor-NLS binding sites. We also present a crystal structure of wild-type MAL RPEL domain in complex with five G-actins. Comparison of the importin-{alpha}- and actin-complexes revealed that the binding of G-actins to MAL is associated with folding of NLS residues into a helical conformation that is inappropriate for importin-{alpha} recognition.

  6. Chilling the Messenger: The Impact of Libel on Community Newspapers.

    Science.gov (United States)

    Hansen, Elizabeth K.; Moore, Roy L.

    A study used a new attitude and behavioral scale for measuring the chilling effect--an undercurrent of fear with respect to publishing decisions--and to determine the impact, if any, of threatened or actual libel suits on community newspapers. The editors and/or publishers of all 167 newspapers in Kentucky with a circulation of less than 50,000…

  7. 77 FR 10772 - Fresh and Chilled Atlantic Salmon From Norway

    Science.gov (United States)

    2012-02-23

    ..., 2011 (76 FR 166) and determined on April 8, 2011 that it would conduct full reviews (76 FR 22422, April..., 2011 (76 FR 38698). The hearing was held in Washington, DC, on November 30, 2011, and all persons who... COMMISSION Fresh and Chilled Atlantic Salmon From Norway Determination On the basis of the record...

  8. Hierarchical system for autonomous sensing-healing of delamination in large-scale composite structures

    International Nuclear Information System (INIS)

    This study combines our hierarchical fiber-optic-based delamination detection system with a microvascular self-healing material to develop the first autonomous sensing-healing system applicable to large-scale composite structures. In this combined system, embedded vascular modules are connected through check valves to a surface-mounted supply tube of a pressurized healing agent while fiber-optic-based sensors monitor the internal pressure of these vascular modules. When delamination occurs, the healing agent flows into the vascular modules breached by the delamination and infiltrates the damage for healing. At the same time, the pressure sensors identify the damaged modules by detecting internal pressure changes. This paper begins by describing the basic concept of the combined system and by discussing the advantages that arise from its hierarchical nature. The feasibility of the system is then confirmed through delamination infiltration tests. Finally, the hierarchical system is validated in a plate specimen by focusing on the detection and infiltration of the damage. Its self-diagnostic function is also demonstrated. (paper)

  9. Structural plasticity and dynamic selectivity of acid-sensing ion channel-spider toxin complexes

    Energy Technology Data Exchange (ETDEWEB)

    Baconguis, Isabelle; Gouaux, Eric [Oregon HSU

    2012-07-29

    Acid-sensing ion channels (ASICs) are voltage-independent, amiloride-sensitive channels involved in diverse physiological processes ranging from nociception to taste. Despite the importance of ASICs in physiology, we know little about the mechanism of channel activation. Here we show that psalmotoxin activates non-selective and Na+-selective currents in chicken ASIC1a at pH7.25 and 5.5, respectively. Crystal structures of ASIC1a–psalmotoxin complexes map the toxin binding site to the extracellular domain and show how toxin binding triggers an expansion of the extracellular vestibule and stabilization of the open channel pore. At pH7.25 the pore is approximately 10Å in diameter, whereas at pH5.5 the pore is largely hydrophobic and elliptical in cross-section with dimensions of approximately 5 by 7Å, consistent with a barrier mechanism for ion selectivity. These studies define mechanisms for activation of ASICs, illuminate the basis for dynamic ion selectivity and provide the blueprints for new therapeutic agents.

  10. Hierarchical system for autonomous sensing-healing of delamination in large-scale composite structures

    Science.gov (United States)

    Minakuchi, Shu; Sun, Denghao; Takeda, Nobuo

    2014-10-01

    This study combines our hierarchical fiber-optic-based delamination detection system with a microvascular self-healing material to develop the first autonomous sensing-healing system applicable to large-scale composite structures. In this combined system, embedded vascular modules are connected through check valves to a surface-mounted supply tube of a pressurized healing agent while fiber-optic-based sensors monitor the internal pressure of these vascular modules. When delamination occurs, the healing agent flows into the vascular modules breached by the delamination and infiltrates the damage for healing. At the same time, the pressure sensors identify the damaged modules by detecting internal pressure changes. This paper begins by describing the basic concept of the combined system and by discussing the advantages that arise from its hierarchical nature. The feasibility of the system is then confirmed through delamination infiltration tests. Finally, the hierarchical system is validated in a plate specimen by focusing on the detection and infiltration of the damage. Its self-diagnostic function is also demonstrated.

  11. Nano-structured interface of graphene and h-BN for sensing applications

    Science.gov (United States)

    de Souza, Fábio A. L.; Amorim, Rodrigo G.; Scopel, Wanderlã L.; Scheicher, Ralph H.

    2016-09-01

    The atomically-precise controlled synthesis of graphene stripes embedded in hexagonal boron nitride opens up new possibilities for the construction of nanodevices with applications in sensing. Here, we explore properties related to the electronic structure and quantum transport of a graphene nanoroad embedded in hexagonal boron nitride, using a combination of density functional theory and the non-equilibrium Green's functions method to calculate the electric conductance. We find that the graphene nanoribbon signature is preserved in the transmission spectra and that the local current is mainly confined to the graphene domain. When a properly sized nanopore is created in the graphene part of the system, the electronic current becomes restricted to a carbon chain running along the border with hexagonal boron nitride. This circumstance could allow the hypothetical nanodevice to become highly sensitive to the electronic nature of molecules passing through the nanopore, thus opening up ways to detect gas molecules, amino acids, or even DNA sequences based on a measurement of the real-time conductance modulation in the graphene nanoroad.

  12. Design Low Crosstalk Ring-Slot Array Structure for Label-Free Multiplexed Sensing

    Directory of Open Access Journals (Sweden)

    Lijun Huang

    2014-08-01

    Full Text Available We theoretically demonstrate a low crosstalk ring-slot array structure used for label-free multiplexed sensing. The proposed sensors array is based on an array of three ring-slot and input/output line defect coupling waveguides. Each ring-slot cavity has slightly different cavity spacing and different resonant frequency. Results obtained using two dimensional finite-difference time-domain (2D-FDTD simulation indicate that the resonant frequencies of each sensor unit in response to the refractive index variations are independent. The refractive index sensitivity is 134 ~ 145.5 nm/RIU (refractive index unit and the Q factors more than 104 can be achieved. The calculated detect limit lower than 1.13 × 10−4 RIU is obtained. In addition, an extremely small crosstalk lower than −25.8 dB is achieved among the array of three ring-slot cavities. The results demonstrate that this multiplexed sensor array is a promising platform for integrated optical devices and enables highly parallel label-free detection.

  13. Fabrication and Sensing Performance of Smart Composite Structures Using Optical Fibre Sensors

    Institute of Scientific and Technical Information of China (English)

    C Y Wei; S W James; C C Ye; R P Tatam; P E lrving

    2000-01-01

    This paper determines the performance of Fibre Bragg Grating (FBG) sensors for strain sensing applications in carbon fibre composite materials. Carbon fibre laminates in either cross-plied or quasiisotropic stacking sequences were fabricated using T300/Hexcel 914 prepregs. The FBG optical sensors were either surface attached, or embedded within laminates. The sensor orientation was aligned either parallel or transverse to the adjacent carbon fibre layers. The composite structures with integrated FBG sensors were subjected to static tensile loading. A scanning fibre Fabry-Perot filter was used to monitor the reflected Bragg wavelengths. The optical sensor embedded between two 90° carbon fibre plies shows a high sensitivity to multi-site cracking formed in the transverse plies. The embedding in 90° plies seems to change the local stress distributions and to become a source of crack initiation. Efficient stress transfer from the host materials to the sensors is dependent upon incorporation methods, the thickness of the adhesive layers, and the location of the sensors.

  14. Reduced graphene oxide functionalized with Cu nanoparticles: Fabrication, structure, and sensing properties

    Energy Technology Data Exchange (ETDEWEB)

    Na, Han Gil; Cho, Hong Yeon; Kwon, Yong Jung; Kang, Sung Yong [Division of Materials Science and Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Lee, Chongmu [Department of Materials Science and Engineering, Inha University, Incheon 402-751 (Korea, Republic of); Jung, Taek Kyun [Department of Materials Science and Engineering, Inha University, Incheon 402-751 (Korea, Republic of); Rare Metals R& D Group, Korea Institute of Industrial Technology, 7-47 Songdo-dong, Yeonsu-gu, Incheon 406-840 (Korea, Republic of); Lee, Hyo-Soo [Rare Metals R& D Group, Korea Institute of Industrial Technology, 7-47 Songdo-dong, Yeonsu-gu, Incheon 406-840 (Korea, Republic of); Kim, Hyoun Woo, E-mail: hyounwoo@hanyang.ac.kr [Division of Materials Science and Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of)

    2015-08-03

    We have fabricated the NO{sub 2} gas sensors by using reduced graphene oxide (RGO) functionalized with copper (Cu) nanoparticles, revealing that the sensitivity was significantly enhanced by the Cu functionalization. Transmission electron microscopy indicated that the nanoparticles with a cubic Cu phase were attached on the surface of RGO. Raman spectra revealed that the structural disorder of RGO was increased by the Cu-functionalization. We performed the NO{sub 2} gas sensing test, revealing that the sensor response of RGOs was increased by 326% by means of the Cu-functionalization. We have discussed the associated mechanisms. In addition, we have ascribed the functionalization-induced changes of response and recovery times to the increase of low-energy binding sites. - Highlights: • We fabricated NO{sub 2} gas sensors by using RGOs functionalized with Cu nanoparticles. • The sensitivity was significantly enhanced by the Cu functionalization. • We examined changes in response and recovery times by the Cu functionalization.

  15. Ultrasonic Sensing and Life Prediction for the DARPA Structural Integrity Prognosis System

    Science.gov (United States)

    Michaels, Jennifer E.; Michaels, Thomas E.; Cobb, Adam C.; Kacprzynski, Gregory J.

    2007-03-01

    The overall objective of the DARPA Structural Integrity Prognosis System (SIPS) program is to develop technologies to advance material damage state condition assessment with limited or no dedicated maintenance action. As a part of the sensors thrust area, an in situ ultrasonic sensing method was developed and demonstrated to detect cracks initiating from fastener holes and provide an estimate of total crack area. Crack area estimates were combined with load history data, projected future loads, and life prediction models to determine a probability density function for time-to-failure. The ultrasonic method utilizes two shear wave angle beam transducers operating in through transmission mode which are mounted on either side of the hole. The transmitted wave travels through the area of expected cracking, and the presence of cracks around the fastener holes decreases the amount of acoustic energy that is received. Furthermore, as cracks open and close during the fatigue process, the received energy is modulated, i.e., decreased when the cracks are open versus closed, and this non-linear behavior is the basis of algorithms developed to detect and size fastener holes cracks. The ultrasonic method was demonstrated as part of an integrated SIPS demonstration whereby aircraft-grade aluminum subcomponents were fatigued to failure. Results are presented from both the ultrasonic measurements and the integrated life prediction software.

  16. Direct metal micropatterning on needle-type structures towards bioimpedance and chemical sensing applications

    Science.gov (United States)

    Kim, Sanghyeok; Park, Jae-ho; Kang, Kyungnam; Park, Chong-Ook; Park, Inkyu

    2015-01-01

    Direct metal patterning methods, such as screen printing, inkjet printing and gravure/flexography printing, are widely used to form electrodes or interconnections for printed electronic devices due to their inexpensive, simple and rapid fabrication as compared to vacuum-based conventional metallization processes. Here, we present direct metal patterning by modified screen printing on the curved surface of needle-type rod structures (i.e. rods with radius of ρ < 1 mm). We achieved various microscale patterns such as straight lines, zigzag lines, wavy lines and alphabetic words with a minimum width of 70 µm on the surface of the rod. Also, four pairs of line patterns were printed on the single rod for electrical interconnection. Printed patterns on the surface of the rod were used as electrodes for the control of a light emission diode (LED) as well as the real-time electrochemical impedance spectroscopy of electrolyte solutions and solid objects by the rod insertion. Furthermore, needles with multiple pairs of microelectrodes were used to measure the electrical impedance of biological samples such as fat and muscle tissues of porcine meat. In addition, a needle-type probe sensor with gas sensing capability was demonstrated by using a needle with printed Ag electrodes and Pd thin films.

  17. In-shore ship extraction from HR optical remote sensing image via salience structure and GIS information

    Science.gov (United States)

    Ren, Xiaoyuan; Jiang, Libing; Tang, Xiao-an

    2015-12-01

    In order to solve the problem of in-shore ship extraction from remote sensing image, a novel method for in-shore ship extraction from high resolution (HR) optical remote sensing image is proposed via salience structure feature and GIS information. Firstly, the berth ROI is located in the image with the aid of the prior GIS auxiliary information. Secondly, the salient corner features at ship bow are extracted from the berth ROI precisely. Finally, a recursive algorithm concerning the symmetric geometry of the ship target is conducted to discriminate the multi docked in-shore targets into mono in-shore ships. The results of the experiments show that the method proposed in this paper can detect the majority of large and medium scale in-shore ships from the optical remote sensing image, including both the mono and the multi adjacent docked in-shore ship cases.

  18. Plasmonic 3D-structures based on silver decorated nanotips for biological sensing

    Science.gov (United States)

    Coluccio, M. L.; Francardi, M.; Gentile, F.; Candeloro, P.; Ferrara, L.; Perozziello, G.; Di Fabrizio, E.

    2016-01-01

    Recent progresses in nanotechnology fabrication gives the opportunity to build highly functional nano-devices. 3D structures based on noble metals or covered by them can be realized down to the nano-scales, obtaining different devices with the functionalities of plasmonic nano-lenses or nano-probes. Here, nano-cones decorated with silver nano-grains were fabricated using advanced nano-fabrication techniques. In fabricating the cones, the angle of the apex was varied over a significant range and, in doing so, different geometries were realized. In depositing the silver nano-particles, the concentration of solution was varied, whereby different growth conditions were realized. The combined effect of tip geometry and growth conditions influences the size and distribution of the silver nano grains. The tips have the ability to guide or control the growth of the grains, in the sense that the nano-particles would preferentially distribute along the cone, and especially at the apex of the cone, with no o minor concentration effects on the substrate. The arrangement of metallic nano-particles into three-dimensional (3D) structures results in a Surface Enhanced Raman Spectroscopy (SERS) device with improved interface with analytes compared to bi-dimensional arrays of metallic nanoparticles. In the future, similar devices may find application in microfluidic devices, and in general in flow chambers, where the system can be inserted as to mimic a a nano-bait, for the recognition of specific biomarkers, or the manipulation and chemical investigation of single cells directly in native environments with good sensitivity, repeatability and selectivity.

  19. Plasmonic 3D-structures based on silver decorated nanotips for biological sensing

    KAUST Repository

    Coluccio, M. L.

    2015-05-01

    Recent progresses in nanotechnology fabrication gives the opportunity to build highly functional nano-devices. 3D structures based on noble metals or covered by them can be realized down to the nano-scales, obtaining different devices with the functionalities of plasmonic nano-lenses or nano-probes. Here, nano-cones decorated with silver nano-grains were fabricated using advanced nano-fabrication techniques. In fabricating the cones, the angle of the apex was varied over a significant range and, in doing so, different geometries were realized. In depositing the silver nano-particles, the concentration of solution was varied, whereby different growth conditions were realized. The combined effect of tip geometry and growth conditions influences the size and distribution of the silver nano grains. The tips have the ability to guide or control the growth of the grains, in the sense that the nano-particles would preferentially distribute along the cone, and especially at the apex of the cone, with no o minor concentration effects on the substrate. The arrangement of metallic nano-particles into three-dimensional (3D) structures results in a Surface Enhanced Raman Spectroscopy (SERS) device with improved interface with analytes compared to bi-dimensional arrays of metallic nanoparticles. In the future, similar devices may find application in microfluidic devices, and in general in flow chambers, where the system can be inserted as to mimic a a nano-bait, for the recognition of specific biomarkers, or the manipulation and chemical investigation of single cells directly in native environments with good sensitivity, repeatability and selectivity. © 2015 Elsevier Ltd.

  20. On the Radiative Transfer Based Remote Sensing of Forest Structure and Leaf Biochemistry (Invited)

    Science.gov (United States)

    Knyazikhin, Y.

    2013-12-01

    invariant approach and illustrate its application for retrieving canopy structural information and leaf albedo from remote sensing. The latter is the only optical variable that conveys information about leaf properties such as pigment concentrations, other chemical constituents and internal structures and therefore is directly related to leaf biochemistry.

  1. Forest and Shrub Canopy Structure from Multiangle and High Resolution Passive Remote Sensing

    Science.gov (United States)

    Chopping, M. J.; Wang, Z.; Bull, M. A.; Duchesne, R.; North, M.

    2015-12-01

    The 3-D structure of forest and shrub canopies can be mapped using diverse technologies, with the most advanced being lidar and interferometric radar. Other approaches include various modes of interpretation of multi-angle imagery, high-resolution stereo photogrammetry, plant identification, delineation, and measurement from high-resolution panchromatic imagery, and image texture metrics. While active remote sensing will revolutionize mapping of canopy structure, there are currently limitations. High precision lidar will remain limited geographically until the launch of NASA's innovative Global Ecosystem Dynamics Investigation to the International Space Station in 2019 but even this mission will not see high latitude boreal forest, taiga, or shrubs in tundra because of the orbit. Radar-based methods must be calibrated using high quality data. Imagery from passive imagers acquired at a range of scales therefore has much value if it can be used to provide structure data at broader geographic and temporal scales. Here we report on canopy mapping at scales from 0.5 m to 250 m using high-resolution panchromatic imagery from satellite imagers and NASA's Multiangle Imaging Spectro-Radiometer (MISR), respectively. MISR-based 250 m aboveground biomass maps for the southwestern U.S. were assessed against the radar-derived North American Carbon Program National Biomass and Carbon Dataset 2000, showing good agreement (R2=0.80, RMSE=31 Mg ha-1 for the validation data set; and 0.76 and 18 Mg ha-1, respectively, for 1013 random points). For Oregon forests the best and worst cases were R2=0.90, RMSE=42 Mg ha-1 and R2=0.78, RMSE=62 Mg ha-1, respectively. For improved validation, the CANAPI algorithm was used to interpret high-resolution panchromatic imagery. In Sierra National forest, California, canopy cover estimates agreed well with those from field inventory (R2=0.92, RMSE=0.03). Height estimates gave R2=0.94 and relative RMSE=0.25 m for the range 3 m - 60 m, vs. lidar

  2. A versatile building block: the structures and functions of negative-sense single-stranded RNA virus nucleocapsid proteins.

    Science.gov (United States)

    Sun, Yuna; Guo, Yu; Lou, Zhiyong

    2012-12-01

    Nucleocapsid protein (NPs) of negative-sense single-stranded RNA (-ssRNA) viruses function in different stages of viral replication, transcription, and maturation. Structural investigations show that -ssRNA viruses that encode NPs preliminarily serve as structural building blocks that encapsidate and protect the viral genomic RNA and mediate the interaction between genomic RNA and RNA-dependent RNA polymerase. However, recent structural results have revealed other biological functions of -ssRNA viruses that extend our understanding of the versatile roles of virally encoded NPs. PMID:23136065

  3. Structured nonlinear optical materials for LIDAR-based remote sensing Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This NASA Phase II STTR effort will develop domain-engineered magnesium oxide doped lithium niobate (MgO:LN) for LIDAR-based remote sensing and communication...

  4. Urban structure analysis of mega city Mexico City using multisensoral remote sensing data

    OpenAIRE

    Taubenböck, Hannes; Esch, Thomas; Wurm, Michael; Thiel, Michael; Ullmann, Tobias; Roth, Achim; Schmidt, Michael; Mehl, Harald; Dech, Stefan

    2008-01-01

    Mega city Mexico City is ranked the third largest urban agglomeration to date around the globe. The large extension as well as dynamic urban transformation and sprawl processes lead to a lack of up-to-date and area-wide data and information to measure, monitor, and understand the urban situation. This paper focuses on the capabilities of multisensoral remotely sensed data to provide a broad range of products derived from one scientific field – remote sensing – to support urban man...

  5. An autonomous unmanned aerial vehicle sensing system for structural health monitoring of bridges

    Science.gov (United States)

    Reagan, Daniel; Sabato, Alessandro; Niezrecki, Christopher; Yu, Tzuyang; Wilson, Richard

    2016-04-01

    As civil infrastructure (i.e. bridges, railways, and tunnels) continues to age; the frequency and need to perform inspection more quickly on a broader scale increases. Traditional inspection and monitoring techniques (e.g., visual inspection, mechanical sounding, rebound hammer, cover meter, electrical potential measurements, ultrasound, and ground penetrating radar) may produce inconsistent results, require lane closure, are labor intensive and time-consuming. Therefore, new structural health monitoring systems must be developed that are automated, highly accurate, minimally invasive, and cost effective. Three-dimensional (3D) digital image correlation (DIC) systems have the merits of extracting full-field strain, deformation, and geometry profiles. These profiles can then be stitched together to generate a complete integrity map of the area of interest. Concurrently, unmanned aerial vehicles (UAVs) have emerged as valuable resources for positioning sensing equipment where it is either difficult to measure or poses a risk to human safety. UAVs have the capability to expedite the optical-based measurement process, offer increased accessibility, and reduce interference with local traffic. Within this work, an autonomous unmanned aerial vehicle in conjunction with 3D DIC was developed for monitoring bridges. The capabilities of the proposed system are demonstrated in both laboratory measurements and data collected from bridges currently in service. Potential measurement influences from platform instability, rotor vibration and positioning inaccuracy are also studied in a controlled environment. The results of these experiments show that the combination of autonomous flight with 3D DIC and other non-contact measurement systems provides a valuable and effective civil inspection platform.

  6. Structural Controls on Groundwater Flow in Basement Terrains: Geophysical, Remote Sensing, and Field Investigations in Sinai

    KAUST Repository

    Mohamed, Lamees

    2015-07-09

    An integrated [very low frequency (VLF) electromagnetic, magnetic, remote sensing, field, and geographic information system (GIS)] study was conducted over the basement complex in southern Sinai (Feiran watershed) for a better understanding of the structural controls on the groundwater flow. The increase in satellite-based radar backscattering values following a large precipitation event (34 mm on 17–18 January 2010) was used to identify water-bearing features, here interpreted as preferred pathways for surface water infiltration. Findings include: (1) spatial analysis in a GIS environment revealed that the distribution of the water-bearing features (conductive features) corresponds to that of fractures, faults, shear zones, dike swarms, and wadi networks; (2) using VLF (43 profiles), magnetic (7 profiles) techniques, and field observations, the majority (85 %) of the investigated conductive features were determined to be preferred pathways for groundwater flow; (3) northwest–southeast- to north–south-trending conductive features that intersect the groundwater flow (southeast to northwest) at low angles capture groundwater flow, whereas northeast–southwest to east–west features that intersect the flow at high angles impound groundwater upstream and could provide potential productive well locations; and (4) similar findings are observed in central Sinai: east–west-trending dextral shear zones (Themed and Sinai Hinge Belt) impede south to north groundwater flow as evidenced by the significant drop in hydraulic head (from 467 to 248 m above mean sea level) across shear zones and by reorientation of regional flow (south–north to southwest–northeast). The adopted integrated methodologies could be readily applied to similar highly fractured basement arid terrains elsewhere. © 2015 Springer Science+Business Media Dordrecht

  7. Effects of Chilling and Partial Freezing on Rigor Mortis Changes of Bighead Carp (Aristichthys nobilis) Fillets: Cathepsin Activity, Protein Degradation and Microstructure of Myofibrils.

    Science.gov (United States)

    Lu, Han; Liu, Xiaochang; Zhang, Yuemei; Wang, Hang; Luo, Yongkang

    2015-12-01

    To investigate the effects of chilling and partial freezing on rigor mortis changes in bighead carp (Aristichthys nobilis), pH, cathepsin B, cathepsin B+L activities, SDS-PAGE of sarcoplasmic and myofibrillar proteins, texture, and changes in microstructure of fillets at 4 °C and -3 °C were determined at 0, 2, 4, 8, 12, 24, 48, and 72 h after slaughter. The results indicated that pH of fillets (6.50 to 6.80) was appropriate for cathepsin function during the rigor mortis. For fillets that were chilled and partially frozen, the cathepsin activity in lysosome increased consistently during the first 12 h, followed by a decrease from the 12 to 24 h, which paralleled an increase in activity in heavy mitochondria, myofibrils and sarcoplasm. There was no significant difference in cathepsin activity in lysosomes between fillets at 4 °C and -3 °C (P > 0.05). Partially frozen fillets had greater cathepsin activity in heavy mitochondria than chilled samples from the 48 to 72 h. In addition, partially frozen fillets showed higher cathepsin activity in sarcoplasm and lower cathepsin activity in myofibrils compared with chilled fillets. Correspondingly, we observed degradation of α-actinin (105 kDa) by cathepsin L in chilled fillets and degradation of creatine kinase (41 kDa) by cathepsin B in partially frozen fillets during the rigor mortis. The decline of hardness for both fillets might be attributed to the accumulation of cathepsin in myofibrils from the 8 to 24 h. The lower cathepsin activity in myofibrils for fillets that were partially frozen might induce a more intact cytoskeletal structure than fillets that were chilled. PMID:26555873

  8. CTAB-Assisted Hydrothermal Synthesis of WO3 Hierarchical Porous Structures and Investigation of Their Sensing Properties

    Directory of Open Access Journals (Sweden)

    Dan Meng

    2015-01-01

    Full Text Available WO3 hierarchical porous structures were successfully synthesized via cetyltrimethylammonium bromide- (CTAB- assisted hydrothermal method. The structure and morphology were investigated using scanning electron microscope, X-ray diffractometer, transmission electron microscopy, X-ray photoelectron spectra, Brunauer-Emmett-Teller nitrogen adsorption-desorption, and thermogravimetry and differential thermal analysis. The result demonstrated that WO3 hierarchical porous structures with an orthorhombic structure were constructed by a number of nanoparticles about 50–100 nm in diameters. The H2 gas sensing measurements showed that well-defined WO3 hierarchical porous structures with a large specific surface area exhibited the higher sensitivity compared with products without CTAB at all operating temperatures. Moreover, the reversible and fast response to H2 gas and good selectivity were obtained. The results indicated that the WO3 hierarchical porous structures are promising materials for gas sensors.

  9. Chilling Tolerance Improving of Watermelon Seedling by Salicylic Acid Seed and Foliar Application

    Directory of Open Access Journals (Sweden)

    Mohammad SAYYARI

    2013-02-01

    Full Text Available Chilling temperatures lead to numerous physiological disturbances in the cells of chilling-sensitive plants and result in chilling injury and death of tropical and subtropical plants such as watermelon. In this study, the possibility of cold stress tolerance enhancing of watermelon seedling (Citrullus lanatus by exogenous application of Salicylic acid (SA was investigated. SA was applied through seed soaking or foliar spray at 0, 0.5, 1 and 1.5 mM concentration. After SA treatment, the seedlings were subjected to chilling 5 h/day at 4°C for 5 days. Statistical analysis showed significant effects of the application methods and SA concentrations on plant growth parameters, photosynthetic pigments, electrolyte leakage, proline and chilling injury index. SA application improved growth parameters and increased chlorophyll content of watermelon seedling subjected to chilling stress and provided significant protection against chilling stress compared to non-SA-treated seedlings. Although two SA application methods improved chilling stress tolerance, seed soaking method provided better protection compared to foliar spray method. SA ameliorated the injury caused by chilling stress via inhibiting proline accumulation and leaf electrolyte leakage. The highest cold tolerance was obtained with 0.5 mM SA application. Results indicate that SA could be used effectively to protect watermelon seedling from damaging effects of chilling stress at the early stages of growth.

  10. Predicting tropical forest stand structure parameters from Fourier transform of very high-resolution remotely sensed canopy images

    OpenAIRE

    Couteron, Pierre; Pelissier, Raphaël; Nicolini, Eric,; Paget, P.

    2005-01-01

    1. Predicting stand structure parameters for tropical forests from remotely sensed data has numerous important applications, such as estimating above-ground biomass and carbon stocks and providing spatial information for forest mapping and management planning, as well as detecting potential ecological determinants of plant species distributions. As an alternative to direct measurement of physical attributes of the vegetation and individual tree crown delineation, we present a powerful holisti...

  11. Remote Sensing of Sonoran Desert Vegetation Structure and Phenology with Ground-Based LiDAR

    OpenAIRE

    Sankey, Joel B.; Munson, Seth M.; Webb, Robert H.; Wallace, Cynthia S.A.; Cesar M. Duran

    2014-01-01

    Long-term vegetation monitoring efforts have become increasingly important for understanding ecosystem response to global change. Many traditional methods for monitoring can be infrequent and limited in scope. Ground-based LiDAR is one remote sensing method that offers a clear advancement to monitor vegetation dynamics at high spatial and temporal resolution. We determined the effectiveness of LiDAR to detect intra-annual variability in vegetation structure at a long-term Sonoran Desert moni...

  12. Hopc: a Novel Similarity Metric Based on Geometric Structural Properties for Multi-Modal Remote Sensing Image Matching

    Science.gov (United States)

    Ye, Yuanxin; Shen, Li

    2016-06-01

    Automatic matching of multi-modal remote sensing images (e.g., optical, LiDAR, SAR and maps) remains a challenging task in remote sensing image analysis due to significant non-linear radiometric differences between these images. This paper addresses this problem and proposes a novel similarity metric for multi-modal matching using geometric structural properties of images. We first extend the phase congruency model with illumination and contrast invariance, and then use the extended model to build a dense descriptor called the Histogram of Orientated Phase Congruency (HOPC) that captures geometric structure or shape features of images. Finally, HOPC is integrated as the similarity metric to detect tie-points between images by designing a fast template matching scheme. This novel metric aims to represent geometric structural similarities between multi-modal remote sensing datasets and is robust against significant non-linear radiometric changes. HOPC has been evaluated with a variety of multi-modal images including optical, LiDAR, SAR and map data. Experimental results show its superiority to the recent state-of-the-art similarity metrics (e.g., NCC, MI, etc.), and demonstrate its improved matching performance.

  13. Characterisation and modelling of defect formation in direct-chill cast AZ80 alloy

    International Nuclear Information System (INIS)

    Wrought magnesium alloys for demanding structural applications require high quality defect free cast feedstock. The aim of this study was to first identify and characterise typical defects in direct chill cast magnesium–aluminium–zinc (AZ) alloy billet and then use modelling to understand the origins of these defects so they can be prevented. Defects were first located using ultrasonic inspection and were then characterised using X-ray computed tomography (XCT) and serial sectioning, establishing the presence of oxide films and intermetallic particles Al8Mn5 in all defects. A model was developed to predict the flow patterns and growth kinetics of the intermetallic phases during casting, which influence the formation of defects. Simulation of the growth of the intermetallic particles demonstrated that precipitation from the liquid occurs in the mould. The combination of the entrained oxide films and intermetallic particles recirculates in the liquid metal and continues to grow, until large enough to settle, which is predicted to occur at the centre of the mould where the flow is the slowest. Based on these predictions, strategies to reduce the susceptibility to defect formation are suggested. - Highlights: • Casting defects in magnesium direct chill casting have been imaged and characterised in 3-dimensions. • The occurrences of co-located clusters of particles and oxide films have been characterised and explained. • A coupled model has been developed to help interpret the observed trend for defects located towards the centre of billets

  14. Characterisation and modelling of defect formation in direct-chill cast AZ80 alloy

    Energy Technology Data Exchange (ETDEWEB)

    Mackie, D.; Robson, J.D.; Withers, P.J. [School of Materials, University of Manchester, Manchester M13 9PL (United Kingdom); Turski, M. [Magnesium Elektron UK, Rake Lane, Manchester, M27 8BF (United Kingdom)

    2015-06-15

    Wrought magnesium alloys for demanding structural applications require high quality defect free cast feedstock. The aim of this study was to first identify and characterise typical defects in direct chill cast magnesium–aluminium–zinc (AZ) alloy billet and then use modelling to understand the origins of these defects so they can be prevented. Defects were first located using ultrasonic inspection and were then characterised using X-ray computed tomography (XCT) and serial sectioning, establishing the presence of oxide films and intermetallic particles Al{sub 8}Mn{sub 5} in all defects. A model was developed to predict the flow patterns and growth kinetics of the intermetallic phases during casting, which influence the formation of defects. Simulation of the growth of the intermetallic particles demonstrated that precipitation from the liquid occurs in the mould. The combination of the entrained oxide films and intermetallic particles recirculates in the liquid metal and continues to grow, until large enough to settle, which is predicted to occur at the centre of the mould where the flow is the slowest. Based on these predictions, strategies to reduce the susceptibility to defect formation are suggested. - Highlights: • Casting defects in magnesium direct chill casting have been imaged and characterised in 3-dimensions. • The occurrences of co-located clusters of particles and oxide films have been characterised and explained. • A coupled model has been developed to help interpret the observed trend for defects located towards the centre of billets.

  15. ChillFish: A Respiration Game for Children with ADHD

    DEFF Research Database (Denmark)

    Sonne, Tobias; Jensen, Mads Møller

    Breathing exercises can help children with ADHD control their stress level, but it can be hard for a child to sustain attention throughout such an exercise. In this paper, we present ChillFish, a breath-controlled biofeedback game designed in collaboration with ADHD professionals to investigate...... the possibilities of combining breathing exercises and game design. Based on a pilot study with 16 adults, we found that playing ChillFish had a positive effect, helping the participants to reach a relaxed state similar to the one offered by traditional breathing exercises. Further, we analyze the opportunities...... and challenges of creating a tangible respiration-based controller and use it as a core game mechanic. Finally, we discuss the challenge of balancing engagement and relaxation in physically controlled games for children with ADHD in order to make a game that can be calming and still sustain their attention....

  16. Structural Mechanisms of Peptide Recognition and Allosteric Modulation of Gene Regulation by the RRNPP Family of Quorum-Sensing Regulators.

    Science.gov (United States)

    Do, Hackwon; Kumaraswami, Muthiah

    2016-07-17

    The members of RRNPP family of bacterial regulators sense population density-specific secreted oligopeptides and modulate the expression of genes involved in cellular processes, such as sporulation, competence, virulence, biofilm formation, conjugative plasmid transfer and antibiotic resistance. Signaling by RRNPP regulators include several steps: generation and secretion of the signaling oligopeptides, re-internalization of the signaling molecules into the cytoplasm, signal sensing by the cytosolic RRNPP regulators, signal-specific allosteric structural changes in the regulators, and interaction of the regulators with their respective regulatory target and gene regulation. The recently determined structures of the RRNPP regulators provide insight into the mechanistic aspects for several steps in this signaling circuit. In this review, we discuss the structural principles underlying peptide specificity, regulatory target recognition, and ligand-induced allostery in RRNPP regulators and its impact on gene regulation. Despite the conserved tertiary structure of these regulators, structural analyses revealed unexpected diversity in the mechanism of activation and molecular strategies that couple the peptide-induced allostery to gene regulation. Although these structural studies provide a sophisticated understanding of gene regulation by RRNPP regulators, much needs to be learned regarding the target DNA binding by yet-to-be characterized RNPP regulators and the several aspects of signaling by Rgg regulators. PMID:27283781

  17. Development of smart piezoelectric transducer self-sensing, self-diagnosis and tuning schemes for structural health monitoring applications

    Science.gov (United States)

    Lee, Sang Jun

    Autonomous structural health monitoring (SHM) systems using active sensing devices have been studied extensively to diagnose the current state of aerospace, civil infrastructure and mechanical systems in near real-time and aims to eventually reduce life-cycle costs by replacing current schedule-based maintenance with condition-based maintenance. This research develops four schemes for SHM applications: (1) a simple and reliable PZT transducer self-sensing scheme; (2) a smart PZT self-diagnosis scheme; (3) an instantaneous reciprocity-based PZT diagnosis scheme; and (4) an effective PZT transducer tuning scheme. First, this research develops a PZT transducer self-sensing scheme, which is a necessary condition to accomplish a PZT transducer self-diagnosis. Main advantages of the proposed self-sensing approach are its simplicity and adaptability. The necessary hardware is only an additional self-sensing circuit which includes a minimum of electric components. With this circuit, the self-sensing parameters can be calibrated instantaneously in the presence of changing operational and environmental conditions of the system. In particular, this self-sensing scheme focuses on estimating the mechanical response in the time domain for the subsequent applications of the PZT transducer self-diagnosis and tuning with guided wave propagation. The most significant challenge of this self-sensing comes from the fact that the magnitude of the mechanical response is generally several orders of magnitude smaller than that of the input signal. The proposed self-sensing scheme fully takes advantage of the fact that any user-defined input signals can be applied to a host structure and the input waveform is known. The performance of the proposed self-sensing scheme is demonstrated by theoretical analysis, numerical simulations and various experiments. Second, this research proposes a smart PZT transducer self-diagnosis scheme based on the developed self-sensing scheme. Conventionally, the

  18. A real-time structural parametric identification system based on fiber optic sensing and neural network algorithms

    Science.gov (United States)

    Wu, Zhishen; Xu, Bin

    2003-07-01

    A structural parametric identification strategy based on neural networks algorithms using dynamic macro-strain measurements in time domain from a long-gage strain sensor by fiber optic sensing technique such as Fiber Bragg Grating (FBG) sensor is developed. An array of long-gage sensors is bounded on the structure to measure reliably and accurately macro-strains. By the proposed methodology, the structural parameter of stiffness can be identified. A beam model with known mass distribution is considered as an object structure. Without any eigenvalue analysis or optimization computation, the structural parameter of stiffness can be identified. First an emulator neural network is presented to identify the beam structure in current state. Free vibration macro-strain responses of the beam structure are used to train the emulator neural network. The trained emulator neural network can be used to forecast the free vibration macro-strain response of the beam structure with enough precision and decide the difference between the free vibration macro-strain responses of other assumed structure with different structural parameters and those of the original beam structure. The root mean square (RMS) error vector is presented to evaluate the difference. Subsequently, corresponding to each assumed structure with different structural parameters, the RMS error vector can be calculated. By using the training data set composed of the structural parameters and RMS error vector, a parametric evaluation neural network is trained. A beam structure is considered as an existing structure, based on the trained parametric evaluation neural network, the stiffness of the beam structure can be forecast. It is shown that the parametric identification strategy using macro-strain measurement from long-gage sensors has the potential of being a practical tool for a health monitoring methodology applied to civil engineering structures.

  19. The Crystal Structure of Burkholderia cenocepacia DfsA Provides Insights into Substrate Recognition and Quorum Sensing Fatty Acid Biosynthesis.

    Science.gov (United States)

    Spadaro, Francesca; Scoffone, Viola C; Chiarelli, Laurent R; Fumagalli, Marco; Buroni, Silvia; Riccardi, Giovanna; Forneris, Federico

    2016-06-14

    Burkholderia cenocepacia is a major concern among respiratory tract infections in cystic fibrosis patients. This pathogen is particularly difficult to treat because of its high level of resistance to the clinically relevant antimicrobial agents. In B. cenocepacia, the quorum sensing cell-cell communication system is involved in different processes that are important for bacterial virulence, such as biofilm formation and protease and siderophore production. Targeting the enzymes involved in this process represents a promising therapeutic approach. With the aim of finding effective quorum sensing inhibitors, we have determined the three-dimensional structure of B. cenocepacia diffusible factor synthase A, DfsA. This bifunctional crotonase (dehydratase/thioesterase) produces the characteristic quorum sensing molecule of B. cenocepacia, cis-2-dodecenoic acid or BDSF, starting from 3-hydroxydodecanoyl-acyl carrier protein. Unexpectedly, the crystal structure revealed the presence of a lipid molecule in the catalytic site of the enzyme, which was identified as dodecanoic acid. Our biochemical characterization shows that DfsA is able to use dodecanoyl-acyl carrier protein as a substrate, demonstrating that dodecanoic acid, the product of this reaction, is released very slowly from the DfsA active site, therefore acting as a DfsA inhibitor. This molecule shows an unprecedented conformational arrangement inside the DfsA active site. In contrast with previous hypotheses, our data illustrate how DfsA and closely related homologous enzymes can recognize long hydrophobic substrates without large conformational changes or assistance by additional regulator molecules. The elucidation of the substrate binding mode in DfsA provides the starting point for structure-based drug discovery studies targeting B. cenocepacia quorum sensing-assisted virulence. PMID:27198181

  20. Local spatial structure of forest biomass and its consequences for remote sensing of carbon stocks

    Directory of Open Access Journals (Sweden)

    M. Réjou-Méchain

    2014-04-01

    Full Text Available Advances in forest carbon mapping have the potential to greatly reduce uncertainties in the global carbon budget and to facilitate effective emissions mitigation strategies such as REDD+. Though broad scale mapping is based primarily on remote sensing data, the accuracy of resulting forest carbon stock estimates depends critically on the quality of field measurements and calibration procedures. The mismatch in spatial scales between field inventory plots and larger pixels of current and planned remote sensing products for forest biomass mapping is of particular concern, as it has the potential to introduce errors, especially if forest biomass shows strong local spatial variation. Here, we used 30 large (8–50 ha globally distributed permanent forest plots to quantify the spatial variability in aboveground biomass (AGB at spatial grains ranging from 5 to 250 m (0.025–6.25 ha, and we evaluate the implications of this variability for calibrating remote sensing products using simulated remote sensing footprints. We found that the spatial sampling error in AGB is large for standard plot sizes, averaging 46.3% for 0.1 ha subplots and 16.6% for 1 ha subplots. Topographically heterogeneous sites showed positive spatial autocorrelation in AGB at scales of 100 m and above; at smaller scales, most study sites showed negative or nonexistent spatial autocorrelation in AGB. We further show that when field calibration plots are smaller than the remote sensing pixels, the high local spatial variability in AGB leads to a substantial "dilution" bias in calibration parameters, a bias that cannot be removed with current statistical methods. Overall, our results suggest that topography should be explicitly accounted for in future sampling strategies and that much care must be taken in designing calibration schemes if remote sensing of forest carbon is to achieve its promise.

  1. Thermoeconomic evaluation of air conditioning system with chilled water storage

    International Nuclear Information System (INIS)

    Highlights: • A new thermoeconomic evaluation methodology has been presented. • The relationship between thermodynamic and economic performances has been revealed. • A key point for thermal storage technology further application is discovered. • A system has been analyzed via the new method and EUD method. - Abstract: As a good load shifting technology for power grid, chilled energy storage has been paid more and more attention, but it always consumes more energy than traditional air conditioning system, and the performance analysis is mostly from the viewpoint of peak-valley power price to get cost saving. The paper presents a thermoeconomic evaluation methodology for the system with chilled energy storage, by which thermodynamic performance influence on cost saving has been revealed. And a system with chilled storage has been analyzed, which can save more than 15% of power cost with no energy consumption increment, and just certain difference between peak and valley power prices can make the technology for good economic application. The results show that difference between peak and valley power prices is not the only factor on economic performance, thermodynamic performance of the storage system is the more important factor, and too big price difference is a barrier for its application, instead of for more cost saving. All of these give a new direction for thermal storage technology application

  2. Chill-inducing music enhances altruism in humans

    Directory of Open Access Journals (Sweden)

    Hajime eFukui

    2014-10-01

    Full Text Available Music is a universal feature of human cultures, and it has both fascinated and troubled many researchers. In this paper we show through the Dictator Game that an individual’s listening to preferred chill-inducing music may promote altruistic behavior that extends beyond the bounds of kin selection or reciprocal altruism. Participants were 22 undergraduate and postgraduate students who were divided into two groups, the In-group (IG and the Out-group (OG, and they acted as dictators. The dictators listened to their own preferred chill-inducing music, to music they disliked, or to silence, and then played the Dictator Game. In this hypothetical experiment, the dictators were given real money (which they did not keep and were asked to distribute it to the recipients, who were presented as stylized images of men and women displayed on a computer screen. The dictators played the Dictator Game both before and after listening to the music. Both male and female dictators gave more money after listening to their preferred music and less after listening to the music they disliked, whereas silence had no effect on the allocated amounts. The group to which the recipient belonged did not influence these trends. The results suggest that listening to preferred chill-inducing music promotes altruistic behavior.

  3. Chill-inducing music enhances altruism in humans.

    Science.gov (United States)

    Fukui, Hajime; Toyoshima, Kumiko

    2014-01-01

    Music is a universal feature of human cultures, and it has both fascinated and troubled many researchers. In this paper we show through the dictator game (DG) that an individual's listening to preferred "chill-inducing" music may promote altruistic behavior that extends beyond the bounds of kin selection or reciprocal altruism. Participants were 22 undergraduate and postgraduate students who were divided into two groups, the in-group and the out-group, and they acted as dictators. The dictators listened to their own preferred "chill-inducing" music, to music they disliked, or to silence, and then played the DG. In this hypothetical experiment, the dictators were given real money (which they did not keep) and were asked to distribute it to the recipients, who were presented as stylized images of men and women displayed on a computer screen. The dictators played the DG both before and after listening to the music. Both male and female dictators gave more money after listening to their preferred music and less after listening to the music they disliked, whereas silence had no effect on the allocated amounts. The group to which the recipient belonged did not influence these trends. The results suggest that listening to preferred "chill-inducing" music promotes altruistic behavior. PMID:25389411

  4. Geological-structural interpretation using products of remote sensing in the region of Carrancas, Minas Gerais, Brazil

    Science.gov (United States)

    Parada, N. D. J. (Principal Investigator); Dossantos, A. R.; Dosanjos, C. E.; Barbosa, M. P.; Veneziani, P.

    1982-01-01

    The efficiency of some criteria developed for the utilization of small scale and low resolution remote sensing products to map geological and structural features was demonstrated. Those criteria were adapted from the Logical Method of Photointerpretation which consists of textural qualitative analysis of landforms and drainage net patterns. LANDSAT images of channel 5 and 7, 4 LANDSAT-RBV scenes, and 1 radar mosiac were utilized. The region of study is characterized by supracrustal metassediments (quartzites and micaschist) folded according to a "zig-zag" pattern and gnaissic basement. Lithological-structural definition was considered outstanding when compared to data acquired during field work, bibliographic data and geologic maps acquired in larger scales.

  5. Chemical sensing and imaging in microfluidic pore network structures relevant to natural carbon cycling and industrial carbon sequestration

    Energy Technology Data Exchange (ETDEWEB)

    Grate, Jay W.; Zhang, Changyong; Wilkins, Michael J.; Warner, Marvin G.; Anheier, Norman C.; Suter, Jonathan D.; Kelly, Ryan T.; Oostrom, Martinus

    2013-06-11

    Energy and climate change represent significant factors in global security. Atmospheric carbon dioxide levels, while global in scope, are influenced by pore-scale phenomena in the subsurface. We are developing tools to visualize and investigate processes in pore network microfluidic structures with transparent covers as representations of normally-opaque porous media. In situ fluorescent oxygen sensing methods and fluorescent cellulosic materials are being used to investigate processes related to terrestrial carbon cycling involving cellulytic respiring microorganisms. These structures also enable visualization of water displacement from pore spaces by hydrophobic fluids, including carbon dioxide, in studies related to carbon sequestration.

  6. Impact of the sampling method and chilling on the Salmonella recovery from pig carcasses.

    Science.gov (United States)

    Vanantwerpen, Gerty; De Zutter, Lieven; Berkvens, Dirk; Houf, Kurt

    2016-09-01

    Differences in recovery of Salmonella on pig carcasses using non-destructive and destructive sampling methods is not well understood in respect to the chilling processes applied in slaughterhouses. Therefore, in two slaughterhouses, four strains at two different concentrations were inoculated onto pork skin. Inoculated skin samples were sampled before and after chilling with two sampling methods: swabbing and destruction. Both slaughterhouses were visited three times and all tests were performed in triplicate. All samples were analysed using the ISO-method and recovered isolates were confirmed by PFGE. The chilling system (fast or conventional cooling) nor the sampling step (before and after chilling) did not significantly influence the recovery of Salmonella. However, swabbing after chilling leads to an underestimation of the real number of contaminated carcasses. Therefore, destructive sampling is the more designated sampling method after chilling. PMID:27236225

  7. Quality effect of freeze-chilling in cod and rainbow trout

    DEFF Research Database (Denmark)

    Jensen, Louise Helene Søgaard; Nielsen, Jette; Jørgensen, Bo;

    staff combines the different meal components to a complete meal. Freeze-chilling is a process consisting of freezing and frozen storage followed by thawing and chilled storage and could be an ideal technique to combine with the concept of meal elements. Freeze-chilling would enable manufacturers...... to produce large quantities of frozen meal elements to be released into the chill chain according to market demands. This procedure would allow the products to thaw during transport, and by arrival the thawed meal elements would be ready for use or chill storage. We have studied the influence of freeze...... is practically applicable and cod and rainbow trout seem potential candidates for freeze-chilled meal elements....

  8. Geolgical Structure Mapping of the Bentong-Raub Suture Zone, Peninsular Malaysia Using Palsar Remote Sensing Data

    Science.gov (United States)

    Beiranvand Pour, A.; Hashim, M.

    2015-10-01

    The Bentong-Raub Suture Zone (BRSZ) of peninsular Malaysia was selected as case study to evaluate the capability of the Phased Array type L-band Synthetic Aperture Radar (PALSAR) satellite remote sensing data for structural geology mapping in tropical environments. The structural elements in the BRSZ were enhanced using multi-polarization configuration of PALSAR data at a regional scale. Adaptive local sigma and directional filters were applied to PALSAR data for detailed structural mapping. Numerous tectonic lineaments with consistent variation in trend, length and density were detected in the study area. Structural analysis of the BRSZ reveals that two distinct parts can be defined, a western part affected mainly by ductile fabrics in the Cameron Highlands and an eastern part affected mainly by brittle deformation in the BRSZ. Ductile deformation indicates several generation of folding in the Cameron Highlands. Several faults, joints and fractures represent brittle deformation events in the BRSZ. The results of this study demonstrate the usefulness of PALSAR satellite remote sensing data for mapping geological structures in tropical environments.

  9. GEOLGICAL STRUCTURE MAPPING OF THE BENTONG-RAUB SUTURE ZONE, PENINSULAR MALAYSIA USING PALSAR REMOTE SENSING DATA

    Directory of Open Access Journals (Sweden)

    A. Beiranvand Pour

    2015-10-01

    Full Text Available The Bentong-Raub Suture Zone (BRSZ of peninsular Malaysia was selected as case study to evaluate the capability of the Phased Array type L-band Synthetic Aperture Radar (PALSAR satellite remote sensing data for structural geology mapping in tropical environments. The structural elements in the BRSZ were enhanced using multi-polarization configuration of PALSAR data at a regional scale. Adaptive local sigma and directional filters were applied to PALSAR data for detailed structural mapping. Numerous tectonic lineaments with consistent variation in trend, length and density were detected in the study area. Structural analysis of the BRSZ reveals that two distinct parts can be defined, a western part affected mainly by ductile fabrics in the Cameron Highlands and an eastern part affected mainly by brittle deformation in the BRSZ. Ductile deformation indicates several generation of folding in the Cameron Highlands. Several faults, joints and fractures represent brittle deformation events in the BRSZ. The results of this study demonstrate the usefulness of PALSAR satellite remote sensing data for mapping geological structures in tropical environments.

  10. Fly's proprioception-inspired micromachined strain-sensing structure: idea, design, modeling and simulation, and comparison with experimental results

    International Nuclear Information System (INIS)

    A new strain-sensing structure inspired from insect's (especially the Fly) propricoception sensor is devised. The campaniform sensillum is a strain-sensing microstructure with very high sensitivity despite its small dimension (diameter ∼10 μm in a relatively stiff material of insect's exocuticle (E = ∼109 Pa). Previous work shows that the high sensitivity of this structure towards strain is due to its membrane-in-recess- and strainconcentrating-hole-features. Based on this inspiration, we built similar structure using silicon micromachining technology. Then a simple characterisation setup was devised. Here, we present briefly, finite-element modeling and simulation based on this actual sample preparation for the characterisation. As comparison and also to understand mechanical features responsible for the strain-sensitivity, we performed the modeling on different mechanical structures: bulk chunk, blind-hole, through-hole, surface membrane, and membrane-in-recess. The actual experimental characterisation was performed previously using optical technique to membrane in-recess micromachined Si structure. The FEM simulation results confirm that the bending stress and strain are concentrated in the hole-vicinity. The membrane inside the hole acts as displacement transducer. The FEM is in conformity with previous analytical results, as well as the optical characterisation result. The end goal is to build a new type MEMS strain sensor

  11. Fly's proprioception-inspired micromachined strain-sensing structure: idea, design, modeling and simulation, and comparison with experimental results

    Science.gov (United States)

    Wicaksono, D. H. B.; Zhang, L.-J.; Pandraud, G.; French, P. J.; Vincent, J. F. V.

    2006-04-01

    A new strain-sensing structure inspired from insect's (especially the Fly) propricoception sensor is devised. The campaniform sensillum is a strain-sensing microstructure with very high sensitivity despite its small dimension (diameter ~10 µm in a relatively stiff material of insect's exocuticle (E = ~109 Pa). Previous work shows that the high sensitivity of this structure towards strain is due to its membrane-in-recess- and strainconcentrating- hole- features. Based on this inspiration, we built similar structure using silicon micromachining technology. Then a simple characterisation setup was devised. Here, we present briefly, finite-element modeling and simulation based on this actual sample preparation for the characterisation. As comparison and also to understand mechanical features responsible for the strain-sensitivity, we performed the modeling on different mechanical structures: bulk chunk, blind-hole, thorugh-hole, surface membrane, and membrane-in-recess. The actual experimental characterisation was performed previously using optical technique to membranein- recess micromachined Si structure. The FEM simulation results confirm that the bending stress and strain are concentrated in the hole-vicinity. The membrane inside the hole acts as displacement transducer. The FEM is in conformity with previous analytical results, as well as the optical characterisation result. The end goal is to build a new type MEMS strain sensor.

  12. Metal Decoration Effects on the Gas-Sensing Properties of 2D Hybrid-Structures on Flexible Substrates

    Directory of Open Access Journals (Sweden)

    Byungjin Cho

    2015-09-01

    Full Text Available We have investigated the effects of metal decoration on the gas-sensing properties of a device with two-dimensional (2D molybdenum disulfide (MoS2 flake channels and graphene electrodes. The 2D hybrid-structure device sensitively detected NO2 gas molecules (>1.2 ppm as well as NH3 (>10 ppm. Metal nanoparticles (NPs could tune the electronic properties of the 2D graphene/MoS2 device, increasing sensitivity to a specific gas molecule. For instance, palladium NPs accumulate hole carriers of graphene/MoS2, electronically sensitizing NH3 gas molecules. Contrarily, aluminum NPs deplete hole carriers, enhancing NO2 sensitivity. The synergistic combination of metal NPs and 2D hybrid layers could be also applied to a flexible gas sensor. There was no serious degradation in the sensing performance of metal-decorated MoS2 flexible devices before/after 5000 bending cycles. Thus, highly sensitive and endurable gas sensor could be achieved through the metal-decorated 2D hybrid-structure, offering a useful route to wearable electronic sensing platforms.

  13. "Literariness," Formalism, and Sense Making: The Line and Stanza Structure of Human Thought.

    Science.gov (United States)

    Gee, James Paul

    1989-01-01

    Uses the "line and stanza" method to analyze and compare texts representing different cultural backgrounds and ages. Proposes that the textual characteristics identified by the Formalists as the measure of literature are actually the hallmarks of a cross-cultural human capacity for making deep sense of experience. (FMW)

  14. Sediment concentration and bed form structures of Gulf of Cambay from remote sensing

    Digital Repository Service at National Institute of Oceanography (India)

    Kunte, P.D.

    of construction of pipelines. All these studies have been attempted either around the Gulf or the towards southern side of the GoC. The present study is focused on the estimation of sediment concentration and mapping of features observed using remote sensing...

  15. Quantitative remote sensing for monitoring forest canopy structural variables in the Three Gorges region of China

    NARCIS (Netherlands)

    Zeng, Y.

    2008-01-01

    Bridging various scales ranging from local to regional and global, remote sensing has facilitated extraordinary advances in modeling and mapping ecosystems and their functioning. Since forests are one of the most important natural resources on the terrestrial Earth surface, accurate and up-to-date i

  16. Physiological and Biochemical Mechanisms of Seed Priming-Induced Chilling Tolerance in Rice Cultivars

    OpenAIRE

    Hussain, Saddam; Khan, Fahad; Hussain, Hafiz A.; Nie, Lixiao

    2016-01-01

    Rice belongs to tropical and subtropical environments and is extremely sensitive to chilling stress particularly during emergence and early stages of seedling development. Seed priming can be a good approach to enhance rice germination and stand establishment under chilling stress. The present study examined the role of different seed priming techniques viz., hydropriming, osmopriming, redox priming, chemical priming, and hormonal priming, in enhancing the chilling tolerance in rice. The most...

  17. Dormancy release and chilling requirement of buds of latitudinal ecotypes of Betula pendula and B. pubescens.

    Science.gov (United States)

    Myking, T; Heide, O M

    1995-11-01

    Bud burst and dormancy release of latitudinal ecotypes of Betula pendula Roth and B. pubescens Ehrh. from Denmark ( approximately 56 degrees N), mid-Norway ( approximately 64 degrees N) and northern Norway ( approximately 69 degrees N) were studied in controlled environments. Dormant seedlings were chilled at 0, 5 or 10 degrees C from October 4 onward and then, at monthly intervals from mid-November to February, batches of seedlings were held at 15 degrees C in an 8-h (SD) or 24-h (LD) photoperiod to permit flushing. A decline in days to bud burst occurred with increasing chilling time in all ecotypes. In November, after 44 chilling days, time to bud burst was least in plants chilled at 0 and 5 degrees C. The difference diminished with increasing chilling time, and in February, after 136 chilling days, bud burst was earliest in plants chilled at 10 degrees C. Long photoperiods during flushing significantly reduced thermal time after short chilling periods (44 and 74 days), but had no effect when the chilling requirement was fully met after 105 or more chilling days. No significant difference in these responses was found between the two species. In both species, chilling requirement decreased significantly with increasing latitude of origin. Bud burst was normal in seedlings overwintered at 12 degrees C, but was erratic and delayed in seedlings overwintered at 15 and especially at 21 degrees C, indicating that the critical overwintering temperature is between 12 and 15 degrees C. We conclude that there is little risk of a chilling deficit in birch under Scandinavian winter conditions even with a climatic warming of 7-8 degrees C. The likely effects of a climatic warming include earlier bud burst, a longer growing season and increased risk of spring frost injury, especially in high latitude ecotypes. PMID:14965987

  18. Reestablishment of ion homeostasis during chill-coma recovery in the cricket Gryllus pennsylvanicus

    OpenAIRE

    MacMillan, Heath A.; Williams, Caroline M.; Staples, James F.; Sinclair, Brent J.

    2012-01-01

    The time required to recover from cold-induced paralysis (chill-coma) is a common measure of insect cold tolerance used to test central questions in thermal biology and predict the effects of climate change on insect populations. The onset of chill-coma in the fall field cricket (Gryllus pennsylvanicus, Orthoptera: Gryllidae) is accompanied by a progressive drift of Na+ and water from the hemolymph to the gut, but the physiological mechanisms underlying recovery from chill-coma are not unders...

  19. Effect of Ni7+ Ion Irradiation on Structure and Ammonia Sensing Properties of Thermally Oxidized Zinc and Indium Films

    Institute of Scientific and Technical Information of China (English)

    Amandeep Kaur Bal; Rafinder Singh; R.K. Bedi

    2012-01-01

    ZnO and In203 films were prepared by thermal oxidation of vacuum deposited zinc and indium films, respec- tively onto the glass substrate at 30 ℃. The fabricated films have been irradiated with 100-MeV Ni7+ ions at different fluences ranging from 5×1011 to 5×1013 ions/cm2. The structural and gas sensing properties of pristine and irradiated films have been discussed. X-ray diffraction (XRD) pattern of pristine and irradiated films reveal that the films are polycrystalline in nature and crystallinity increases after irradiation. In this study, highly porous In203 nanorods evolved when being irradiated at a fluence of 5×1013 ions/cm2 while ZnO film shows decrease in number of nanowires. The ammonia sensing performance of the Ni^7+ irradiated In203 films shows an improvement as compared to its pristine counterpart.

  20. Tenderness of Pork Muscles as Influenced by Chilling Rate and Altered Carcass Suspension

    DEFF Research Database (Denmark)

    Kirkegaard, Elin; Møller, Anders Juel

    1987-01-01

    Evaluation of tenderness improvements in porcine muscles (longissimus dorsi, semimembranosus, biceps femoris) in 72 carcasses by using combinations of three different chilling rates and two different suspennnsion methods....

  1. Design and Analysis of Multilayered Waveguide Structure With Metal-Dielectric Gratings for Sensing With Reflection Narrowband Notch Filter

    Directory of Open Access Journals (Sweden)

    Guiju ZHANG

    2015-11-01

    Full Text Available Developments in micro and nanofabrication technologies have led a variety of grating waveguide structures (GWS being proposed and implemented in optics and laser application systems. A new design of multilayered nanostructure double-grating is described for reflection notch filter. Thin metal film and dielectric film are used and designed with one-dimensional composite gratings. The results calculated by rigorous coupled-wave analysis (RCWA present that the thin metal film between substrate and grating can produce significant attenuated reflections and efficiency in a broad reflected spectral range. The behavior of such a reflection filter is evaluated for refractive index sensing, which can be applied inside the integrated waveguide structure while succeeding cycles in measurement. The filter peaks are designed and obtained in a visible range with full width half maximum (FWHM of several nanometers to less than one nanometer. The multilayered structure shows a sensitivity of refractive index of 220nm/RIU as changing the surroundings. The reflection spectra are studied under different periods, depths and duty cycles. The passive structure and its characteristics can achieve practical applications in various fields, such as optical sensing, color filtering, Raman spectroscopy and laser technology.DOI: http://dx.doi.org/10.5755/j01.ms.21.4.9625

  2. Investigation of structural geology and coal mine subsidence potential in Colorado Springs area using remote sensing and GIS technology

    International Nuclear Information System (INIS)

    The purpose of this paper is to determine the extent to which remote structures which may affect the location and migration of subsidence over abandoned underground coal mines in the Colorado Springs area. Ultimately, these techniques could be useful for identifying such geologic structures at other abandoned mine land (AML) sites. Landsat satellite images and aerial photographs were used to interpret the geologic structure of the area. A geographic information system (GIS) was used to integrate the diverse data sets involved in the study and to allow reliable and reproducible spatial registration and analysis of the data. The specific study area used was the northern and northeastern Colorado Springs, Colorado, area where coal mining was active from the 1870s until 1957. The results of this study indicate that the subsidence hazard zones projected by Dames and Moore (1985) could be modified to take into account geologic structures as identified through remote sensing. Other AML sites should be investigated through remote sensing and lineament analysis to aid in fully evaluating subsidence potential of the sites. The GIS database also will provide a reasonably reliable source of spatial data for future land-use planning and tracking of subsidence hazards

  3. Flood Damage Modeling on the Basis of Urban Structure Mapping Using High-Resolution Remote Sensing Data

    Directory of Open Access Journals (Sweden)

    Tina Gerl

    2014-08-01

    Full Text Available The modeling of flood damage is an important component for risk analyses, which are the basis for risk-oriented flood management, risk mapping, and financial appraisals. An automatic urban structure type mapping approach was applied on a land use/land cover classification generated from multispectral Ikonos data and LiDAR (Light Detection And Ranging data in order to provide spatially detailed information about the building stock of the case study area of Dresden, Germany. The multi-parameter damage models FLEMOps (Flood Loss Estimation Model for the private sector and regression-tree models have been adapted to the information derived from remote sensing data and were applied on the basis of the urban structure map. To evaluate this approach, which is suitable for risk analyses, as well as for post-disaster event analyses, an estimation of the flood losses caused by the Elbe flood in 2002 was undertaken. The urban structure mapping approach delivered a map with a good accuracy of 74% and on this basis modeled flood losses for the Elbe flood in 2002 in Dresden were in the same order of magnitude as official damage data. It has been shown that single-family houses suffered significantly higher damages than other urban structure types. Consequently, information on their specific location might significantly improve damage modeling, which indicates a high potential of remote sensing methods to further improve risk assessments.

  4. THE EFFECTS OF SPRAY-CHILLING ASSOCIATED TO CONVENTIONAL CHILLING ON MASS LOSS, BACTERIOLOGYCAL AND PHYSICO-CHEMICAL QUALITY OF BEEF CARCASS

    Directory of Open Access Journals (Sweden)

    Moacir Evandro Lage

    2006-10-01

    Full Text Available The purpose of this study was to verify the effect of conventional air chilling associated to intermittent spray-chilling treatment, on weight loss, physico-chemical and bacteriological quality of beef carcasses. Two plants of commercial beef slaughterhouse located in Goiânia and fiscalized by the Federal Inspection Service were used to develop the research. The spray-chilling treatment was accomplished in an intermittent way, commanded by acontrolled logical program, with cycles of 90 seconds, in intervals of 30 minutes, during the first 4 hours of the chilling process. Physico-chemical and bacteriological analysis were made in spray-chilled water and carcasses samples, according to recommendation of the effective legislation.The average values of carcasses weight loss of treatment group were lower to the ones verified for the control group,in both plants, A and B, (P < 0,001, showing a high economic potential. As a conclusion of physico-chemical and bacteriological analysis results of water and meat samples, it is clear that the technology of chilling beef carcasses inthe conventional system associated to spraying did not interfere in the quality of meat, and it can become an analysis object on part of official organs for sanitary regulation and fiscalization, for its definitive adoption. KEY WORDS: Spray-chilling, shrinkage, beef carcass.

  5. A Rice CaMBP Gene is Induced in Organ-Specific Manner by Both Chilling and Heat-Shock Treatments

    Institute of Scientific and Technical Information of China (English)

    WAN Jia; XI Jiang; DU Zhi-ru; XU Zheng-jun

    2008-01-01

    A rice CaMBP gene, OsCaMBP (AB363406), was isolated from a chilling treated rice using the fluorescent differential display (FDD) screening method. Its cDNA sequence (2094 bp) contains an opening reading frame (ORF) encoding a 569 amino acids protein (63.2 kD). OsCaMBP has the typical structural features of the CaMBP family, including the conserved IQ calmodulin-binding motif at the N-terminus. Homology analysis revealed 38.25%-47.28% identities of OsCaMBP with other CaMBPs in plants. RT-PCR analysis showed that the expression of OsCaMBP was remarkably inducible under the chilling (8℃) and heat-shock (42℃) treatments. OsCaMBP was undetectable under the normal conditions, and induced under the chilling treatment for 1 h, as well as the heat-shock treatment for 15 min, suggesting that the gene plays important roles in the signaling pathway in rice under both chilling and heat-shock stresses.

  6. Structure, ferroelectric and gas sensing properties of sol-gel derived (Ba,Sr)(Ti,Zr)O3 thin films

    International Nuclear Information System (INIS)

    In this paper, the effect of Zr addition on the crystalline structure, ferroelectric and gas sensing properties of sol-gel derived barium strontium titanate (BST) thin films have been studied. Thin films of Zr doped BST were deposited by spin coating technique on silicon and platinum coated silicon wafers. Zr addition in BST thin films results in increase of lattice parameter and tensile strain due to larger ionic radius of Zr ions compared to Ti ions. However, due to slower diffusion rate inside BST lattice, the crystallite size of combined BSTZ system decreases. Reduction of crystallite size affects the ferroelectric behaviour of BSTZ thin films by influencing the polarization contribution from individual domains. This causes a decrease of the spontaneous polarization and also results in slimmer P-E hysteresis loop with increasing Zr content in the BST films. Gas sensing characteristics were tested with by exposing the films to ammonia gas. The sensitivity increases while the response times decreases with increasing Zr content in the BST films. The improvement in ammonia sensing response has been attributed to reduced crystallite size in BSTZ thin films

  7. Remote sensing as a preliminary analysis for the detection of active tectonic structures: an application to the Albanian orogenic system

    Directory of Open Access Journals (Sweden)

    Andrea Favretto

    2013-12-01

    Full Text Available As is well known, both the traditional direct geological and geophysical survey methods used to identify geologic features are very expensive and time-consuming procedures. In this regard, remote sensing methods applied to multispectral and medium spatial resolution satellite images allow a more focused approach with respect to the more specific geologic methods. This is achieved by a preliminary land inspection carried out by the semi-automated analysis of satellite imagery. This avoids wasting resources as the geological/geophysical survey methods can be later applied only to those zones suspected of having certain tectonic activity (derived by the remotely sensed imagery. This paper will evaluate an ASTER sensor satellite image (and its derived Digital Elevation Model or DEM, in order to point out the suspected presence of active geologic structures (faults. The area in question is west – central Albania. The results of the remote sensing procedures are later compared with the established data for the same area taken by satellite images, in order to verify the reliability of the adopted method. The source of the established data has been from the bibliography.

  8. Hydrothermal Synthesis and Structural Characterization of NiO/SnO2 Composites and Hydrogen Sensing Properties

    Directory of Open Access Journals (Sweden)

    Chao Wei

    2015-01-01

    Full Text Available Pure SnO2 and NiO doped SnO2 nanostructures were successfully synthesized via a simple and environment-friendly hydrothermal method. X-ray powder diffraction (XRD, scanning electron microscopy (SEM, energy dispersive X-ray spectroscopy (EDS, and X-ray photoelectron spectra (XPS were used to investigate the crystalline structures, surface morphologies and microstructures, and element components and their valences of the as-synthesized samples. Furthermore, planar chemical gas sensors based on the synthesized pure SnO2 and NiO/SnO2 composites were fabricated and their sensing performances to hydrogen, an important fault characteristic gas dissolved in power transformer oil, were investigated in detail. Gas sensing experiments indicate that the NiO/SnO2 composites showed much higher gas response and lower working temperature than those of pure SnO2, which could be ascribed to the formation of p-n heterojunctions between p-type NiO and n-type SnO2. These results demonstrate that the as-synthesized NiO/SnO2 composites a promising hydrogen sensing material.

  9. Dark-chilling of Seedlings Affects Initiation and Morphology of Broccoli Inflorescence

    Directory of Open Access Journals (Sweden)

    Aneta GRABOWSKA

    2013-05-01

    Full Text Available The constant supply of broccoli heads for a vegetable market can be kept by the differentiation of sowing time and the age of seedlings. Dark-chilling of young seedlings can also modify the time of transplanting, subsequent plant development, yield and inflorescence quality. The aim of the present study was to analyze the influence of seedling dark-chilling on the inflorescence initiation and the morphological quality of broccoli heads. The experiment was carried out at the University of Agriculture in Krakow (South Poland in the years 2009 and 2010, with broccoli (Brassica oleracea L. var. italica Plenck medium late cultivar ‘Monaco’ F1. The examined factors were the age of seedlings (4-, 6-, 8-, and 10-week-old and dark-chilling (2°C/2 weeks and non-chilled control. Microscopic analysis of the apex sections was performed to determine the time of the inflorescence differentiation in chilled and non-chilled seedlings of different age. Chosen morphological features of the mature heads were also described as depended on age and chilling of seedlings. The inflorescence initiation was observed between 4 and 6 week of the plant ontogeny. Especially 4-week-old seedlings, chilled by two weeks, were more advanced in the generative development in comparison to non-chilled control. Low temperature applied in the seedling stage did not cause the head buttoning. Inflorescences developed by broccoli planted from 4 and 6-week-old seedlings, both chilled and control, were characterized by the best visual quality, determined by a convex head shape, tight branching angle, small and uniform size and regular form of flower buds. Chilling of oldest, 8- and 10-week-old seedlings negatively affected the inflorescence quality, through planed and spread shape of heads and non-uniform shape of flower buds.

  10. Study and Optimization of Self-Assembled Polymeric Multilayer Structures with Neutral Red for pH Sensing Applications

    Directory of Open Access Journals (Sweden)

    Javier Goicoechea

    2008-01-01

    Full Text Available The characterization of nanostructured thin films is critical in the design and fabrication of optical sensors. Particularly, this work is a detailed study of the properties of layer-by-layer electrostatic self-assembled multilayer (LbL structures fabricated using poly(allylamine hydrochloride (PAH and Neutral Red (NR as cations, and poly(acrylic acid (PAA as polyanion. These LbL films, due to the colorimetric properties of the NR, are suitable for sensor applications such as pH sensing in the physiological range. In the (PAH+NR/PAA LbL structure, it has been observed a very important influence of the pH of the solutions in the properties of the resultant films. Different techniques such as spectroscopy and atomic force microscopy (AFM are combined to characterize the films, and the results are analyzed showing coherence with previous works. The LbL structure is finally optimized and dramatically improved nanostructured films were fabricated, showing good sensing properties, short response times, and good stability.

  11. Expandable and retractable self-rolled structures based on metal/polymer thin film for flow sensing

    Science.gov (United States)

    Zhu, Jianzhong; White, Carl; Saadat, Mehdi; Bart-Smith, Hilary

    2015-11-01

    Most aquatic animals such as fish rely heavily on their ability of detect and respond to ambient flows in order to explore and inhabit various habitats or survive predator-prey encounters. Fish utilize neuromasts in their skin surface and lateral lines in their bodies to align themselves while swimming upstream for migration, avoid obstacles, reduce locomotion cost, and detect flow variations caused by potential predators. In this study, a thin film MEMS sensor analogous to a fish neuromast has been designed for flow sensing. Residual stress arises in many thin film materials during processing. Metal and polymer thin film materials with a significant difference in elastic modular were chosen to form a multiple-layer structure. Upon releasing, the structure rolls into a tube due to mechanical property mismatch. The self-rolled tube can expand or retract, depending on the existence of external force such as flow. An embedded strain sensor detects the deformation of the tube and hence senses the ambient flow. Numerical simulations were conducted to optimize the structural design. Experiments were performed in a flow tank to quantify the performance of the sensor. This research is supported by the Office of Naval Research under the MURI Grant N00014-14-1-0533.

  12. Utilising a loop structure to allow a microfiber coupler with larger taper diameters to be used for sensing

    Science.gov (United States)

    Wei, Fangfang; Farrell, Gerald; Wu, Qiang; Semenova, Yuliya

    2016-05-01

    This paper examines a technique that utilizes a Sagnac loop with a microfiber coupler (MFC) as a coupler which allows the MFC to operate effectively as a sensor but with larger than normal tapered fiber diameters. The proposed structure is found to be suitable for temperature and refractive index (RI) sensing. It is shown that a variation in the surrounding of the MFC RI results in a shift of the output spectrum, while a temperature variation leads to changes in the intensity of the interference dips. A decrease in the waist diameter of the MFC results in an increase in the sensitivity to temperature. For MFC structures based on a 5.6 μm and a 3 μm fiber waist diameter, the minimum transmission power level of a selected spectral dip decreases by 1.7 dB and 5.03 dB respectively, as the temperature changes from 18 °C to 44 °C. A change in the surrounding RI from 1.334 to 1.395 results in the spectral redshift of 8 nm using a 5.6 μm fiber waist diameter. By functionalizing the surface of the MFC with various materials, the structure could potentially be used for sensing of other parameters.

  13. Chill Down Process of Hydrogen Transport Pipelines

    Science.gov (United States)

    Mei, Renwei; Klausner, James

    2006-01-01

    A pseudo-steady model has been developed to predict the chilldown history of pipe wall temperature in the horizontal transport pipeline for cryogenic fluids. A new film boiling heat transfer model is developed by incorporating the stratified flow structure for cryogenic chilldown. A modified nucleate boiling heat transfer correlation for cryogenic chilldown process inside a horizontal pipe is proposed. The efficacy of the correlations is assessed by comparing the model predictions with measured values of wall temperature in several azimuthal positions in a well controlled experiment by Chung et al. (2004). The computed pipe wall temperature histories match well with the measured results. The present model captures important features of thermal interaction between the pipe wall and the cryogenic fluid, provides a simple and robust platform for predicting pipe wall chilldown history in long horizontal pipe at relatively low computational cost, and builds a foundation to incorporate the two-phase hydrodynamic interaction in the chilldown process.

  14. Graphene nano-devices and nano-composites for structural, thermal and sensing applications

    Science.gov (United States)

    Yavari, Fazel

    In this dissertation we have developed graphene-based nano-devices for applications in integrated circuits and gas sensors; as well as graphene-based nano-composites for applications in structures and thermal management. First, we have studied the bandgap of graphene for semiconductor applications. Graphene as a zero-bandgap material cannot be used in the semiconductor industry unless an effective method is developed to open the bandgap in this material. We have demonstrated that a bandgap of 0.206 eV can be opened in graphene by adsorption of water vapor molecules on its surface. Water molecules break the molecular symmetries of graphene resulting in a significant bandgap opening. We also illustrate that the lack of bandgap in graphene can be used to our advantage by making sensors that are able to detect low concentrations of gas molecules mixed in air. We have shown that 1-2 layers of graphene synthesized by chemical vapor deposition enables detection of trace amounts of NO 2 and NH3 in air at room temperature and atmospheric pressure. The gas species are detected by monitoring changes in electrical resistance of the graphene film due to gas adsorption. The sensor response time is inversely proportional to the gas concentration. Heating the film expels chemisorbed molecules from the graphene surface enabling reversible operation. The detection limits of ~100 parts-per-billion (ppb) for NO2 and ~500 ppb for NH3 obtained using this device are markedly superior to commercially available NO2 and NH3 detectors. This sensor is fabricated using individual graphene sheets that are exquisitely sensitive to the chemical environment. However, the fabrication and operation of devices that use individual nanostructures for sensing is complex, expensive and suffers from poor reliability due to contamination and large variability from sample-to-sample. To overcome these problems we have developed a gas sensor based on a porous 3D network of graphene sheets called graphene foam

  15. Overexpression of violaxanthin de-epoxidase gene alleviates photoinhibition of PSII and PSI in tomato during high light and chilling stress.

    Science.gov (United States)

    Han, Han; Gao, Shan; Li, Bin; Dong, Xin-Chun; Feng, Hai-Long; Meng, Qing-Wei

    2010-02-15

    A tomato (Lycopersicon esculentum) violaxanthin de-epoxidase gene (LeVDE) was isolated. The deduced amino acid sequence of LeVDE showed high identities with violaxanthin de-epoxidase in other plant species. RNA gel blot analysis showed that the mRNA accumulation of LeVDE in the wild-type (WT) was regulated by diurnal rhythm and temperature. RNA and protein gel blot analyses confirmed that the sense LeVDE was transferred into the tomato genome and overexpressed under the control of 35S-CaMV. The ratio of (A+Z)/(V+A+Z) and the values of non-photochemical quenching (NPQ) were higher in transgenic plants than those in WT under high light and chilling stress (4 degrees C). The net photosynthetic rate (Pn) decreased markedly in WT compared to transgenic lines under high light stress. The maximum quantum yield of primary photochemistry of PSII (Fv/Fm) in transgenic plants decreased more slowly during stresses and recovered faster than that in WT under optimal conditions. The oxidizable P700 in transgenic plants was higher than that in WT under chilling stress. These results suggest that overexpression of LeVDE increased the function of the xanthophyll cycle and alleviated photoinhibition of PSII and PSI in tomato during high light and chilling stress with low irradiance.

  16. Effects of chill casting processes on secondary dendrite arm spacing and densification of Al-Si-Mg alloy

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Based on the resin bonded sand casting process, the effects of chill processes on the secondary dendrite arm spacing(SDAS) and densification of Al-Si-Mg alloy were studied. The influences of the chill thickness and effective distance of chill operating on the SDAS were researched; and the effect of chillheat capacity on SDAS was investigated. The result reveals that,SDAS decreases with increasing the thickness of chill but the effect of chill is finite. The effective distance of chill operating for the chill with different thickness were obtained, and the functional relations among modulus, length of castings and thickness of chill were discussed, and the synthetical network chart of the relation among them was plotted. The relationship between local solidification rate and SDAS was defined by means of quadratic polynomial regression.

  17. Fffect of Nisin on Chilled Pork Preservation%Nisin对冷鲜肉保质期的影响

    Institute of Scientific and Technical Information of China (English)

    李巍

    2012-01-01

    [目的]考察乳酸链球菌素(Nisin)对冷鲜肉保藏过程中品质的影响.[方法]将Nisin和山梨酸钾分别置于装有200 g鲜肉的保鲜袋中,放在4℃冰箱中保藏.通过对保藏期的冷鲜肉理化指标和感官指标的评价,考察了Nisin对冷鲜肉保存过程中的汁液损失率、菌落总数、pH、挥发性盐基氮(TVB-N)、硫代巴比妥酸反应物(TBARS)和感官特性等品质指标的影响.[结果]冷鲜肉储藏过程中,加入Nisin后,可使肉体汁液流失较慢,能更有效地使肉体保鲜;可使冷鲜肉保存的时间最长,保质期可达12 d,比加入山梨酸钾的延长了2d.感官评价表明,加入Nisin的肉体在感官上仍呈红色,肉体的弹性和组织状态都较好.[结论]Nisin对冷鲜肉延长保藏期的效果更加明显,可延长冷鲜肉的鲜度和货架期.%[ Objective] The study aimed to investigate the effect of Nisin on the quality of the chilled pork during the preservation. [ Method] The Nisin and potassium sorbet were respectively put into the fresh-keeping bags with 200 g meat and preserved in the refrigerator at 4 ℃. Through the evaluation on the physical and chemical indexes and the senses index of the chilled pork in the preservation period, the effects of the Nisin on the quality parameters such as the loss rate of meat juice,total bacterial count,pH values,total volatile basic nitrogen (TVB-N) ,thiobarbituric acid reactive substance (TBARS) values and the sensory characteristics of the chilled pork in the preservation were investigated. [Result] During the preservation of the chilled pork,adding Nisin could make the lower loss of meat juice,thus more effectively keeping the meat freshness and could make the cold meat preserve the longest period,with the shelf life of 12 d,being extended by 2 d compared with the potassium sorbet. The sensory evaluation showed that after adding the Nisin the meat body was still red on the sensory and was better on the flexibility and

  18. Lifa Air Secure Box method for chilled beam cleaning

    OpenAIRE

    Leppälä, Vesa-Jukka

    2014-01-01

    The objective of this Bachelor’s Thesis was to introduce a chilled beam cleaning method and to develop an improved version for the prototype introduced in 2011. This thesis was commissioned by Lifa Air Ltd. The company itself is specialized in improving Indoor Air Quality and offers a wide range of products meant for ventilation cleaning. The aim for the development work was to fill the requirements and needs set by the company based on the research done, and to construct a working and improv...

  19. Integrated Quality Assurance of Chilled Food Fish at Sea

    DEFF Research Database (Denmark)

    Frederiksen, Marco Thorup; Olsen, Karsten Bæk; Popescu, Valeriu

    1997-01-01

    The aim of the IQAS project is to improve the quality of fresh fish (white fish and flat fish) landed by the Community vessels significantly and to increase the proportion of the fish caught used for food purposes, as well as to improve the on-board working conditions. This will be achieved...... by specifying and developing safe, efficient, mechanized on-board handling systems enabling the catch to be sorted, gutted, bled, characterized for length and weight, prepared quickly and correctly for rapid chilling and to be stored in appropriate, labelled containers at 0°C until sold. A monitoring, measuring...

  20. ChillFish: A Respiration Game for Children with ADHD

    DEFF Research Database (Denmark)

    Sonne, Tobias; Jensen, Mads Møller

    2016-01-01

    Breathing exercises can help children with ADHD control their stress level, but it can be hard for a child to sustain attention throughout such an exercise. In this paper, we present ChillFish, a breath-controlled biofeedback game designed in collaboration with ADHD professionals to investigate...... and challenges of creating a tangible respiration-based controller and use it as a core game mechanic. Finally, we discuss the challenge of balancing engagement and relaxation in physically controlled games for children with ADHD in order to make a game that can be calming and still sustain their attention....

  1. Human Response to Personalized Ventilation Combined with Chilled Ceiling

    DEFF Research Database (Denmark)

    Lipczynska, Aleksandra; Kaczmarczyk, Jan; Marcol, Bartosz;

    2014-01-01

    , the use of radiant ceiling cooling will provide operative temperature lower than the air temperature and will improve further occupants’ thermal comfort at warm environment. Therefore combining PV with chilled ceiling may be an effective way to provide thermal comfort in rooms at temperature higher than...... period subjects’ thermal sensation ranged between warm and hot. After returning to the workstations the use of PV helped subjects to improve their thermal sensation much faster (5 min) compared to the CCMV (30 min). Air at workstation was perceived as more fresh with CCPV than with CCMV. Percentage...

  2. Chill-inducing music enhances altruism in humans

    OpenAIRE

    Fukui, Hajime; Toyoshima, Kumiko

    2014-01-01

    Music is a universal feature of human cultures, and it has both fascinated and troubled many researchers. In this paper we show through the dictator game (DG) that an individual’s listening to preferred “chill-inducing” music may promote altruistic behavior that extends beyond the bounds of kin selection or reciprocal altruism. Participants were 22 undergraduate and postgraduate students who were divided into two groups, the in-group and the out-group, and they acted as dictators. The dictato...

  3. Development of Methods for Structural Characterization of Pantoea stewartii Quorum-Sensing Regulator EsaR

    OpenAIRE

    Pennerman, Kayla Kara

    2014-01-01

    The LuxR family of proteins serves as quorum-sensing transcriptional regulators in proteobacteria. At high population densities, a small acyl-homoserine lactone (AHL) molecule, produced by a LuxI homologue, accumulates in the environment. The LuxR proteins bind to their respective AHL when the ligand accumulates to sufficient levels. Once bound to AHL, the holoproteins usually become functional as transcriptional activators. However, there is a subset of LuxR homologues, the EsaR subfamily, w...

  4. Structural and functional effects of heavy metals on the nervous system, including sense organs, of fish

    DEFF Research Database (Denmark)

    Baatrup, E

    1991-01-01

    metals are well known pollutants in the aquatic environment. Their interaction with relevant chemical stimuli may interfere with the communication between fish and environment. 5. The affinity for a number of ligands and macromolecules makes heavy metals most potent neurotoxins. 6. The present Mini......, including their sense organs, for mediating relevant behaviour such as food search, predator recognition, communication and orientation. 3. Unfortunately, the nervous system is most vulnerable and injuries to its elements may dramatically change the behaviour and consequently the survival of fish. 4. Heavy...

  5. Tomato chilling injury threshold defined by the volatile profiles of pink harvested tomato fruit

    Science.gov (United States)

    Fresh tomato fruit show visible symptoms of chilling injury (CI) when stored at temperatures lower than the reported chilling threshold of 12.5°C. However, their sensitivity has been reported to decrease as they ripen. Volatile profiles change during ripening and are affected by physiological change...

  6. Dual roles for hepatic lectin receptors in the clearance of chilled platelets

    DEFF Research Database (Denmark)

    Rumjantseva, Viktoria; Grewal, Prabhjit K; Wandall, Hans H;

    2009-01-01

    Rapid chilling causes glycoprotein-Ib (GPIb) receptors to cluster on blood platelets. Hepatic macrophage beta(2) integrin binding to beta-N-acetylglucosamine (beta-GlcNAc) residues in the clusters leads to rapid clearance of acutely chilled platelets after transfusion. Although capping the beta-G...

  7. A chilling-resistant agent for seedling raising of early-season rice

    Institute of Scientific and Technical Information of China (English)

    JIANLingcheng; SUNLonghua

    1992-01-01

    Our lab experiments in 1986 and 1987 showed that the CR-4, a kind of chilling-sesistant agent, could obviously increase the chilling resistance of rice seedlings. The survival of seedlings was significantly higher than that of the check when located in low temperature. For example, after the seedlings were treated for 2 d at 1-0℃,

  8. Chilling Tolerance and Physiological Parameters as Influenced by Grafting in Watermelon Seedlings

    Institute of Scientific and Technical Information of China (English)

    LIU Hui-ying; ZHU Zhu-jun; LU Guo-hua; QIAN Qiong-qiu

    2003-01-01

    The influences of different rootstocks on chilling tolerance and physiological parameters in wa-termelon seedlings have been studied. The results showed that grafting improved the chilling tolerance. Com-pared with own-rooted watermelon seedlings, the grafted watermelon seedlings had lower chilling injury index,lower electrolytic leakage (%), lower malondialdehyde (MDA) content, higher chlorophyll and proline con-tent, and higher activities of superoxide dismutase (SOD), ascorbate peroxidase (AsA-POD) and de-hydroascorbate reductase (DR) in the leaves under iow temperature stress. There was a considerable differenceof chilling tolerance among different grafted watermelon seedlings due to the difference of rootstock chillingtolerance. After low temperature treatment, the grafted seedling with higher chilling tolerance had lower elec-trolytic leakage ( %), lower MDA content, higher proline content and higher activities of SOD, AsA-POD andDR in the leaves compared with the grafted seedling with weaker chilling tolerance. From these, we could con-clude that chilling tolerance of watermelon seedlings may be related to higher antioxidative ability and mem-brane stability in the plants. The chilling tolerance of grafted seedling could be properly evaluated by compre-hensive physiological indexes but not a single physiological index.

  9. Impact of personalized ventilation combined with chilled ceiling on eye irritation symptoms

    DEFF Research Database (Denmark)

    Lipczynska, Aleksandra; Marcol, Bartosz; Kaczmarczyk, Jan;

    2014-01-01

    , elevated air movement toward face and increased radiant cooling may have impact on the eye symptoms. Twenty four human subjects participated in experiments with PV combined with chilled ceiling system (CCPV) and with mixing ventilation (MV) combined with chilled ceiling (CCMV). In the experiments with PV...... an impact on their subjective and physiological response....

  10. Chills in Different Sensory Domains: Frisson Elicited by Acoustical, Visual, Tactile and Gustatory Stimuli

    Science.gov (United States)

    Grewe, Oliver; Katzur, Bjorn; Kopiez, Reinhard; Altenmuller, Eckart

    2011-01-01

    "Chills" (frisson manifested as goose bumps or shivers) have been used in an increasing number of studies as indicators of emotions in response to music (e.g., Craig, 2005; Guhn, Hamm, & Zentner, 2007; McCrae, 2007; Panksepp, 1995; Sloboda, 1991). In this study we present evidence that chills can be induced through aural, visual, tactile, and…

  11. Tenderness of Pork Muscles as Influenced by Chilling Rate and Altered Carcass Suspension

    DEFF Research Database (Denmark)

    Kirkegaard, Elin; Møller, Anders Juel

    1987-01-01

    Evaluation of tenderness improvements in porcine muscles (longissimus dorsi, semimembranosus, biceps femoris) in 72 carcasses by using combinations of three different chilling rates and two different suspennnsion methods.......Evaluation of tenderness improvements in porcine muscles (longissimus dorsi, semimembranosus, biceps femoris) in 72 carcasses by using combinations of three different chilling rates and two different suspennnsion methods....

  12. 9 CFR 381.66 - Temperatures and chilling and freezing procedures.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Temperatures and chilling and freezing procedures. 381.66 Section 381.66 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT... Procedures § 381.66 Temperatures and chilling and freezing procedures. (a) General. Temperatures...

  13. Structure-function relationships affecting the sensing mechanism of monolayer-protected cluster doped xerogel amperometric glucose biosensors.

    Science.gov (United States)

    DiPasquale, Luke T; Poulos, Nicholas G; Hall, Jackson R; Minocha, Aastha; Bui, Tram Anh; Leopold, Michael C

    2015-07-15

    A systematic study of the structure-function relationships critical to understanding the sensing mechanism of 1st generation amperometric glucose biosensors with an embedded nanoparticle (NP) network is presented. Xerogel-based films featuring embedded glucose oxidase enzyme and doped with alkanethiolate-protected gold NPs, known as monolayer protected clusters (MPCs), exhibit significantly enhanced performance compared to analogous systems without NPs including higher sensitivity, faster response time, and extended linear/dynamic ranges. The proposed mechanism involves diffusion of the glucose to glucose oxidase within the xerogel, enzymatic reaction production of H2O2 with subsequent diffusion to the embedded network of MPCs where it is oxidized, an event immediately reported via fast electron transfer (ET) through the MPC system to the working electrode. Various aspects of the film construct and strategy are systematically probed using amperometry, voltammetry, and solid-state electronic conductivity measurements, including the effects of MPC peripheral chain length, MPC functionalization via place-exchange reaction, MPC core size, and the MPC density or concentration within the xerogel composite films. The collective results of these experiments support the proposed mechanism and identify interparticle spacing and the electronic communication through the MPC network is the most significant factor in the sensing scheme with the diffusional aspects of the mechanism that may be affected by film/MPC hydrophobicity and functionality (i.e., glucose and H2O2 diffusion) shown to be less substantial contributors to the overall enhanced performance. Understanding the structure-function relationships of effective sensing schemes allows for the employment of the strategy for future biosensor design toward clinically relevant targets. PMID:25819004

  14. Low-cost fabrication of optical waveguides, interconnects and sensing structures on all-polymer-based thin foils

    Science.gov (United States)

    Rezem, Maher; Kelb, Christian; Günther, Axel; Rahlves, Maik; Reithmeier, Eduard; Roth, Bernhard

    2016-03-01

    Micro-optical sensors based on optical waveguides are widely used to measure temperature, force and strain but also to detect biological and chemical substances such as explosives or toxins. While optical micro-sensors based on silicon technology require complex and expensive process technologies, a new generation of sensors based completely on polymers offer advantages especially in terms of low-cost and fast production techniques. We have developed a process to integrate micro-optical components such as embedded waveguides and optical interconnects into polymer foils with a thickness well below one millimeter. To enable high throughput production, we employ hot embossing technology, which is capable of reel-to-reel fabrication with a surface roughness in the optical range. For the waveguide fabrication, we used the thermoplastic polymethylmethacrylate (PMMA) as cladding and several optical adhesives as core materials. The waveguides are characterized with respect to refractive indices and propagation losses. We achieved propagation losses are as low as 0.3 dB/cm. Furthermore, we demonstrate coupling structures and their fabrication especially suited to integrate various light sources such as vertical-cavity surface-emitting lasers (VCSEL) and organic light emitting diodes (OLED) into thin polymer foils. Also, we present a concept of an all-polymer and waveguide based deformation sensor based on intensity modulation, which can be fabricated by utilizing our process. For future application, we aim at a low-cost and high-throughput reel-to-reel production process enabling the fabrication of large sensor arrays or disposable single-use sensing structures, which will open optical sensing to a large variety of application fields ranging from medical diagnosis to automotive sensing.

  15. Magnetic field sensing based on magnetic-fluid-clad fiber-optic structure with taper-like and lateral-offset fusion splicing.

    Science.gov (United States)

    Dong, Shaohua; Pu, Shengli; Wang, Haotian

    2014-08-11

    A kind of magnetic field sensor composed of magnetic fluid surrounding a segment of singlemode fiber is proposed. The taper-like and lateral-offset fusion splicing techniques are employed. The sensing principle is based on cladding mode interference. The interference valley wavelength or transmission loss of the sensing structure is sensitive to the external magnetic field, which is utilized for magnetic field sensing. The linear response regions are obtained in the range of 38-225 Oe and 250-475 Oe. For the valley-wavelength-shift-type sensing, the sensitivities are 14.1 pm/Oe and 26 pm/Oe at low and high field ranges, respectively. For the transmission-loss-variation-type sensing, the sensitivity of -0.024 dB/Oe is achieved for the magnetic field strength ranging from 250 to 475 Oe. PMID:25320997

  16. Flower-like hierarchical structures consisting of porous single-crystalline ZnO nanosheets and their gas sensing properties to volatile organic compounds (VOCs)

    International Nuclear Information System (INIS)

    Highlights: • Flower-like hierarchical structures consisting of porous single-crystalline ZnO nanosheets were synthesized. • The flower-like hierarchical structured ZnO exhibited higher response and shorter response and recovery times. • The sensing mechanism of the flower-like hierarchical has been systematically analyzed. - Abstract: Flower-like hierarchical structures consisting of porous single-crystalline ZnO nanosheets (FHPSCZNs) were synthesized by a one-pot wet-chemical method followed by an annealing treatment, which combined the advantages between flower-like hierarchical structure and porous single-crystalline structure. XRD, SEM and HRTEM were used to characterize the synthesized FHPSCZN samples. The sensing properties of the FHPSCZN sensor were also investigated by comparing with ZnO powder sensor, which exhibited higher response and shorter response and recovery times. The sensing mechanism of the FHPSCZN sensor has been further analyzed from the aspects of electronic transport and gas diffusion

  17. Research on corrosion detection for steel reinforced concrete structures using the fiber optical white light interferometer sensing technique

    Science.gov (United States)

    Zhao, Xuefeng; Cui, Yanjun; Wei, Heming; Kong, Xianglong; Zhang, Pinglei; Sun, Changsen

    2013-06-01

    In this paper, a novel kind of steel rebar corrosion monitoring technique for steel reinforced concrete structures is proposed, designed, and tested. The technique is based on the fiber optical white light interferometer (WLI) sensing technique. Firstly, a feasibility test was carried out using an equal-strength beam for comparison of strain sensing ability between the WLI and a fiber Bragg grating (FBG). The comparison results showed that the sensitivity of the WLI is sufficient for corrosion expansion strain monitoring. Then, two WLI corrosion sensors (WLI-CSs) were designed, fabricated, and embedded into concrete specimens to monitor expansion strain caused by steel rebar corrosion. Their performance was studied in an accelerated electrochemical corrosion test. Experimental results show that expansion strain along the fiber optical coil winding area can be detected and measured accurately by the proposed sensor. The advantages of the proposed monitoring technique allow for quantitative corrosion expansion monitoring to be executed in real time for reinforced concrete structures and with low cost.

  18. Research on corrosion detection for steel reinforced concrete structures using the fiber optical white light interferometer sensing technique

    International Nuclear Information System (INIS)

    In this paper, a novel kind of steel rebar corrosion monitoring technique for steel reinforced concrete structures is proposed, designed, and tested. The technique is based on the fiber optical white light interferometer (WLI) sensing technique. Firstly, a feasibility test was carried out using an equal-strength beam for comparison of strain sensing ability between the WLI and a fiber Bragg grating (FBG). The comparison results showed that the sensitivity of the WLI is sufficient for corrosion expansion strain monitoring. Then, two WLI corrosion sensors (WLI-CSs) were designed, fabricated, and embedded into concrete specimens to monitor expansion strain caused by steel rebar corrosion. Their performance was studied in an accelerated electrochemical corrosion test. Experimental results show that expansion strain along the fiber optical coil winding area can be detected and measured accurately by the proposed sensor. The advantages of the proposed monitoring technique allow for quantitative corrosion expansion monitoring to be executed in real time for reinforced concrete structures and with low cost. (paper)

  19. Methods for Sensing and Monitoring Fatigue Cracks and Their Applicability for Marine Structures

    NARCIS (Netherlands)

    Horst, Menno van der; Kaminski, Miroslaw; Puik, Erik

    2013-01-01

    In order to guarantee structural integrity of marine structures in an effective way, operators of these structures seek an affordable, simple and robust system for monitoring detected cracks. Such systems are not yet available and the authors took a challenge to research a possibility of developing

  20. Influence of the ventilation system on thermal comfort of the chilled panel system in heating mode

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Zhe; Ding, Yan; Wang, Shuo; Yin, Xinglei; Wang, Menglei [Tianjin University, Tianjin 300072 (China)

    2010-12-15

    In heating mode, fresh air is still essential for a chilled panel system in order to ensure the indoor air quality. In this paper, a chilled ceiling panel system was designed and built in a typical office room. The thermal environment and thermal comfort in the room were fully measured and evaluated by using the Fanger's PMV-PPD model and the standard of ISO 7730 respectively, when room was heated in two modes, one of which is the chilled panel heating mode and the other of which is the combined heating mode of chilled panel and supply air. The research results indicate that in the combined mode, ceiling ventilation improves the general thermal comfort and reduces the risk of local discomfort. Under the condition of same general thermal comfort, the heating supply upper limit of chilled panel can be increased by 12.3% because of air mixing effect caused by introduction of air ventilation. (author)

  1. Development of transport technique by chilling for melon fly, Bactrocera cucurbitae Coquillett (Diptela: Dephritidae)

    International Nuclear Information System (INIS)

    To evaluate the effect of chilling on mass-reared melon fly, Bactrocera cucurbitae COQ., groups of adult flies were exposed to 3, 0.5, -2.2 and -3.5°C for 6, 12, 24 and 48h. The recovery and longevity of adult chilled for less than 24h at about 0.5°C was not adversely affected. A special container for chilled flies, which was able to keep the temperature below 10°C for 4h, was designed for their long-distance transport. The longevities of flies using aerial distribution by helicopter and hand release on the ground using the chilled transport container were compared with direct release from an emergence box without chilling at Miyagi Island in Okinawa Prefecture. There were no significant differences in longevity between the three release methods

  2. An Inexpensive Radiosonde Chilled Mirror Sensor: An Old Technology With New Impact

    Science.gov (United States)

    Schmidlin, F. J.; Busalacchi, Antonio J. (Technical Monitor)

    1999-01-01

    The availability of an inexpensive chilled mirror dewpoint sensor has made improved atmospheric relative humidity measurements accessible. Comparisons between the chilled mirror sensor and routine radiosonde sensors have provided new information on the limitation and reliability of the routine measurements. The chilled mirror has observed detailed moisture profiles at cirrus cloud levels when cirrus was not visible, a feature that routine sensors fail to observe. Comparison measurements between the chilled mirror, the carbon resistive (hygristor) and, the capacitive sensors will be discussed. Measurements from three locations (Wallops Island; Andros Island, Bahamas; and Camborne, UK) will be highlighted. It is conceivable that the chilled mirror sensor, when its capability is fully understood, may be sufficiently reliable to serve as a reference.

  3. Chemical additive to enhance antimicrobial efficacy of chlorine and control cross-contamination during immersion chill of broiler carcasses

    Science.gov (United States)

    Immersion chilling during broiler processing can be a site for cross contamination between the occasional highly contaminated carcass and those that are co-chilled. Chlorine is often used as a chill tank antimicrobial but it can be overcome with heavy organic loads associated with the constant supp...

  4. Discrimination of the wall effect in a thin counter with micro-gap structure for neutron position sensing

    Energy Technology Data Exchange (ETDEWEB)

    Sakae, Takeji; Manabe, Tohru; Kitamura, Yasunori; Nohtomi, Akihiro [Kyushu Univ., Fukuoka (Japan); Sakamoto, Sigeyasu

    1996-07-01

    Simulation by the Monte Carlo method is applied to estimate the wall effect in a thermal neutron counter having a new function for discriminating the effect. The counter is designed to have paralleled electrodes with micro-gap structure. A resistive anode is used for position sensing on the center of a set of the three electrode. The structure can be made by simple arrangement of anode and cathode wires on an insulator plane. The calculation shows discrimination of the wall effect can be achieved by coincident counting of two or three elements included in the counter. By using the coincident counting, the thickness of the neutron counter can be made into 1 mm with the information of the total energy created in the neutron detection. (author)

  5. A core-shell structured inorganic-organic hybrid nanocomposite for Hg(II) sensing and removal.

    Science.gov (United States)

    Jiqu, Han; Qixia, Yang

    2015-10-01

    In the present paper, a core-shell structured inorganic-organic hybrid nanocomposite for Hg(II) sensing and removal was designed and fabricated, where the core was composed of superparamagnetic Fe3O4 and the shell consisted of molecular silica sieve MCM-41. A rhodamine derived probe was grafted onto the backbone of MCM-41 through a silane coupling reagent to control its loading content. This probe functionalized core-shell structure was confirmed and characterized by XRD analysis, electron microscopy images, IR spectra, thermogravimetry and N2 adsorption/desorption isotherms. It was found that the emission of this composite increased with increasing Hg(II) concentrations but was immune to other metal ions, showing good selectivity and high sensitivity towards Hg(II) ions. A linear Stern-Volmer curve was observed with short response time. In addition, this composite possessed good Hg(II)-removing and recycling performance. PMID:25978016

  6. 冷却肉微生物腐败与冷链系统%Chilled meat microbial spoilage and chill chain system

    Institute of Scientific and Technical Information of China (English)

    金鑫; 周光宏; 徐幸莲

    2012-01-01

    冷却肉极易发生微生物腐败,温度是最关键的影响因素。冷链系统持续的低温能抑制微生物的生长繁殖,预防冷却肉腐败。本文简述了微生物代谢活动对冷却肉腐败的影响,重点将冷链系统分为加工冷链、运输冷链、销售冷链和家庭保藏四部分,分别从概念及存在的问题等方面加以阐述,并展望了其未来有待提高完善的地方。%Chilled meat highly prone to microbial spoilage,temperature seems to be the most important factor that influences the spoilage.Sustained low-temperature of chill chain can inhibit microbial growth and prevent chilled meat spoilage.The effect of microbial metabolism on chilled meat spoilage was briefly introduced.Attention was drawn to the chill chain system which divided into four parts of processing, transportation, retail and domestic storage,and separately discussed the concept and issues of each part. The advance of chilled meat were prosoected as well.

  7. Monitoring tropical and montane forest dynamics and structure using remote sensing

    Science.gov (United States)

    Greenberg, Jonathan Asher

    Uncertainties in our understanding of the basic inputs and dynamics at work in the global carbon cycle severely restrict our ability to address why climate change is happening and how best to mitigate it. I focused on advances in regional and global climate change model inputs, addressing two major uncertainties: (1) what are the anthropogenic factors influencing deforestation and (2) what is the carbon load of an ecosystem? Analysis of anthropogenic factors leading to land use changes are presented in an evaluation of deforestation at the UNESCO Biosphere Reserve, Parque National Yasuni, located in the rainforest of eastern Ecuador, using multitemporal Landsat satellite imagery. Using survival analysis, I assessed current and future trends in deforestation rates and investigated the impact of spatial, cultural, and economic factors on deforestation. I found the annual rate of deforestation is currently only 0.11%, but is increasing with time, so that by 2063, 50% of the forest within 2 km of a major oil access road will be lost due to unhindered colonization and anthropogenic conversion. To improve accuracy in estimating landscape level carbon sequestration, I developed a new approach to generating regional aboveground biomass estimates for tree species of the Lake Tahoe Basin, California using hyperspatial (<1m2) remote sensing imagery. I demonstrate how, with accurate classification maps and allometric equations relating DBH or crown area to biomass, that crown parameters can be used to estimate regional biomass. I show that biomass estimated with fine-scale optical sensors does not saturate at high biomass levels as does coarse-scale optical and RADAR sensors. Finally, I address a technical problem to improve quantitative comparison of remote sensing datasets. I present a modification of the empirical line method for normalizing the radiance or reflectance scales of two images. Radiometric normalization of multitemporal remote sensing datasets is a critical

  8. Effects of Aesthetic Chills on a Cardiac Signature of Emotionality.

    Directory of Open Access Journals (Sweden)

    Maria Sumpf

    Full Text Available Previous studies have shown that a cardiac signature of emotionality (referred to as EK, which can be computed from the standard 12 lead electrocardiogram, ECG, predicts inter-individual differences in the tendency to experience and express positive emotion. Here, we investigated whether EK values can be transiently modulated during stimulation with participant-selected music pieces and film scenes that elicit strongly positive emotion.The phenomenon of aesthetic chills, as indicated by measurable piloerection on the forearm, was used to accurately locate moments of peak emotional responses during stimulation. From 58 healthy participants, continuous EK values, heart rate, and respiratory frequency were recorded during stimulation with film scenes and music pieces, and were related to the aesthetic chills. EK values, as well as heart rate, increased significantly during moments of peak positive emotion accompanied by piloerection.These results are the first to provide evidence for an influence of momentary psychological state on a cardiac signature of emotional personality (as reflected in EK values. The possibility to modulate ECG amplitude signatures via stimulation with emotionally significant music pieces and film scenes opens up new perspectives for the use of emotional peak experiences in the therapy of disorders characterized by flattened emotionality, such as depression or schizoid personality disorder.

  9. Effects of Aesthetic Chills on a Cardiac Signature of Emotionality

    Science.gov (United States)

    Sumpf, Maria; Jentschke, Sebastian; Koelsch, Stefan

    2015-01-01

    Background Previous studies have shown that a cardiac signature of emotionality (referred to as EK, which can be computed from the standard 12 lead electrocardiogram, ECG), predicts inter-individual differences in the tendency to experience and express positive emotion. Here, we investigated whether EK values can be transiently modulated during stimulation with participant-selected music pieces and film scenes that elicit strongly positive emotion. Methodology/Principal Findings The phenomenon of aesthetic chills, as indicated by measurable piloerection on the forearm, was used to accurately locate moments of peak emotional responses during stimulation. From 58 healthy participants, continuous EK values, heart rate, and respiratory frequency were recorded during stimulation with film scenes and music pieces, and were related to the aesthetic chills. EK values, as well as heart rate, increased significantly during moments of peak positive emotion accompanied by piloerection. Conclusions/Significance These results are the first to provide evidence for an influence of momentary psychological state on a cardiac signature of emotional personality (as reflected in EK values). The possibility to modulate ECG amplitude signatures via stimulation with emotionally significant music pieces and film scenes opens up new perspectives for the use of emotional peak experiences in the therapy of disorders characterized by flattened emotionality, such as depression or schizoid personality disorder. PMID:26083383

  10. A spectral-structural bag-of-features scene classifier for very high spatial resolution remote sensing imagery

    Science.gov (United States)

    Zhao, Bei; Zhong, Yanfei; Zhang, Liangpei

    2016-06-01

    Land-use classification of very high spatial resolution remote sensing (VHSR) imagery is one of the most challenging tasks in the field of remote sensing image processing. However, the land-use classification is hard to be addressed by the land-cover classification techniques, due to the complexity of the land-use scenes. Scene classification is considered to be one of the expected ways to address the land-use classification issue. The commonly used scene classification methods of VHSR imagery are all derived from the computer vision community that mainly deal with terrestrial image recognition. Differing from terrestrial images, VHSR images are taken by looking down with airborne and spaceborne sensors, which leads to the distinct light conditions and spatial configuration of land cover in VHSR imagery. Considering the distinct characteristics, two questions should be answered: (1) Which type or combination of information is suitable for the VHSR imagery scene classification? (2) Which scene classification algorithm is best for VHSR imagery? In this paper, an efficient spectral-structural bag-of-features scene classifier (SSBFC) is proposed to combine the spectral and structural information of VHSR imagery. SSBFC utilizes the first- and second-order statistics (the mean and standard deviation values, MeanStd) as the statistical spectral descriptor for the spectral information of the VHSR imagery, and uses dense scale-invariant feature transform (SIFT) as the structural feature descriptor. From the experimental results, the spectral information works better than the structural information, while the combination of the spectral and structural information is better than any single type of information. Taking the characteristic of the spatial configuration into consideration, SSBFC uses the whole image scene as the scope of the pooling operator, instead of the scope generated by a spatial pyramid (SP) commonly used in terrestrial image classification. The experimental

  11. In silico structural analysis of quorum sensing genes in Vibrio fischeri

    Directory of Open Access Journals (Sweden)

    Mohammed Z Al-khayyat

    2015-09-01

    Full Text Available Quorum sensing controls the luminescence of Vibrio fischeri through the transcriptional activator LuxR and the specific autoinducer signal produced by luxI. Amino acid sequences of these two genes were analyzed using bioinformatics tools. LuxI consists of 193 amino acids and appears to contain five α-helices and six ß-sheets when analyzed by SSpro8. LuxI belongs to the autoinducer synthetase family and contains an acetyltransferase domain extending from residues 24 to 110 as MOTIF predicted. LuxR, on the other hand, contains 250 amino acids and has ten α-helices and four ß-sheets. MOTIF predicted LuxR to possess functional motifs; the inducer binding site extending from amino acid residues 23 to 147 and the LuxR activator site extending between amino acids 182 and 236. The InterProScan5 server identified a winged helix-turn-helix DNA binding motif.

  12. Stress and structural damage sensing piezospectroscopic coatings validated with digital image correlation

    Directory of Open Access Journals (Sweden)

    Gregory Freihofer

    2015-03-01

    Full Text Available The piezospectroscopic effect, relating a material’s stress state and spectral signature, has recently demonstrated tailorable sensitivity when the photo-luminescent alpha alumina is distributed in nanoparticulate form within a matrix. Here, the stress-sensing behavior of an alumina-epoxy nanoparticle coating, applied to a composite substrate in an open hole tension configuration, is validated with the biaxial strain field concurrently determined through digital image correlation. The coating achieved early detection of composite failure initiation at 77% failure load, and subsequently tracked stress distribution in the immediate vicinity of the crack as it progressed, demonstrating non-invasive stress and damage detection with multi-scale spatial resolution.

  13. Flexible High Energy-Conversion Sensing Materials for Structural Health Monitoring Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The applicant is developing flexible highly-efficient piezoelectric materials for use in structural health monitoring (SHM) as contemplated in the solicitation...

  14. Nothing about protein structure classification makes sense except in the light of evolution.

    Science.gov (United States)

    Valas, Ruben E; Yang, Song; Bourne, Philip E

    2009-06-01

    In this, the 200th anniversary of Charles Darwin's birth and the 150th anniversary of the publication of the Origin of Species, it is fitting to revisit the classification of protein structures from an evolutionary perspective. Existing classifications use homologous sequence relationships, but knowing that structure is much more conserved that sequence creates an iterative loop from which structures can be further classified beyond that of the domain, thereby teasing out distant evolutionary relationships. The desired classification scheme is then one in which a fold is merely semantics and structure can be classified as either ancestral or derived.

  15. Detecting forest canopy layering: applying lidar remote sensing to further understand the role of vertical structure in species habitat preference

    Science.gov (United States)

    Whitehurst, A. S.; Dubayah, R.; Swatantran, A.

    2011-12-01

    Full waveform lidar reflects off all forest canopy elements, showing not only height, but also the structure within the canopy from the top to the forest floor, making it an ideal remote sensing technology for research in forest ecosystem dynamics. Vertical stratification or canopy layering has long been noted as an essential element in the forest ecosystem and of importance for species habitat. This project explores the utility of lidar for characterizing forest canopy layering and applying canopy layering information to better understand species habitat preference. Canopy layering will be mapped across the landscape using full-waveform lidar remote sensing data from the NASA Goddard Space Flight Center Laser Vegetation Imaging Sensor (LVIS). Two methods for quantifying layering have been developed from LVIS data collected during the summer of 2009 for Hubbard Brook Experimental Forest, New Hampshire. The two layering datasets (one categorical, one continuous) describe how vertical stratification varies across the forest with canopy height and elevation. The relationships between of canopy layering and avian species habitat preference will also be assessed for bird species within Hubbard Brook Experimental forest. These results will provide ecologically meaningful information and a relevant method for quantifying canopy layering at the landscape scale, which will aid in a better understanding of forest ecosystem dynamics for forest management and species habitat research.

  16. Synthesis, Structure, and Ethanol Gas Sensing Properties of In2O3 Nanorods Decorated with Bi2O3 Nanoparticles.

    Science.gov (United States)

    Park, Sunghoon; Kim, Soohyun; Sun, Gun-Joo; Lee, Chongmu

    2015-04-22

    Bi2O3-decorated In2O3 nanorods were synthesized using a one-step process, and their structure, as well as the effects of decoration of In2O3 nanorods with Bi2O3 on the ethanol gas-sensing properties were examined. The multiple networked Bi2O3-decorated In2O3 nanorod sensor showed responses of 171-1774% at ethanol concentrations of 10-200 ppm at 200 °C. The responses of the Bi2O3-decorated In2O3 nanorod sensor were stronger than those of the pristine-In2O3 nanorod sensors by 1.5-4.9 times at the corresponding concentrations. The two sensors exhibited short response times and long recovery times. The optimal Bi concentration in the Bi2O3-decorated In2O3 nanorod sensor and the optimal operation temperature of the sensor were 20% and 200 °C, respectively. The Bi2O3-decorated In2O3 nanorod sensor showed selectivity for ethanol gas over other gases. The origin of the enhanced response, sensing speed, and selectivity for ethanol gas of the Bi2O3-decorated In2O3 nanorod sensor to ethanol gas is discussed.

  17. Compressive sensing of full wave field data for structural health monitoring applications

    DEFF Research Database (Denmark)

    di Ianni, Tommaso; De Marchi, Luca; Perelli, Alessandro;

    2015-01-01

    Numerous nondestructive evaluations and structural health monitoring approaches based on guide waves rely on analysis of wave fields recorded through scanning laser Doppler vibrometers (SLDVs) or ultrasonic scanners. The informative content which can be extracted from these inspections is relevant...

  18. Low cost sensing of vegetation volume and structure with a Microsoft Kinect sensor

    Science.gov (United States)

    Azzari, G.; Goulden, M.

    2011-12-01

    The market for videogames and digital entertainment has decreased the cost of advanced technology to affordable levels. The Microsoft Kinect sensor for Xbox 360 is an infrared time of flight camera designed to track body position and movement at a single-articulation level. Using open source drivers and libraries, we acquired point clouds of vegetation directly from the Kinect sensor. The data were filtered for outliers, co-registered, and cropped to isolate the plant of interest from the surroundings and soil. The volume of single plants was then estimated with several techniques, including fitting with solid shapes (cylinders, spheres, boxes), voxel counts, and 3D convex/concave hulls. Preliminary results are presented here. The volume of a series of wild artichoke plants was measured from nadir using a Kinect on a 3m-tall tower. The calculated volumes were compared with harvested biomass; comparisons and derived allometric relations will be presented, along with examples of the acquired point clouds. This Kinect sensor shows promise for ground-based, automated, biomass measurement systems, and possibly for comparison/validation of remotely sensed LIDAR.

  19. Fabricating neuromast-inspired gel structures for membrane-based hair cell sensing

    Science.gov (United States)

    Tamaddoni, Nima J.; Stephens, Christopher P.; Sarles, S. A.

    2012-04-01

    Recent research has shown that a new class of mechanical sensor, assembled from biomolecules and which features an artificial cell membrane as the sensing element, can be used to mimic basic hair cell mechanotransduction in vertebrates. The work presented in this paper is motivated by the need to increase sensor performance and stability by refining the methods used to fabricate and connect lipid-encapsulated hydrogels. Inspired by superficial neuromasts found on fish, three hydrogel materials are compared for their ability to be readily shaped into neuromast-inspired geometries and enable lipid bilayer formation using self-assembly at an oil/water interface. Agarose, polyethylene glycol (PEG, 6kg/mole), and hydroxyethyl methacrylate (HEMA) gel materials are compared. The results of this initial study determined that UV-curable gel materials such as PEG and HEMA enable more accurate shaping of the gel-needed for developing a sensor that uses a gel material both for mechanical support and membrane formation-compared to agarose. However, the lower hydrophobicity of agarose and PEG materials provide a more fluid, water-like environment for membrane formation-unlike HEMA. In working toward a neuromast-inspired design, a final experiment demonstrates that a bilayer can also be formed directly between two lipid-covered PEG surfaces. These initial results suggest that candidate gel materials with a low hydrophobicity, high fluidity, and a low modulus can be used to provide membrane support.

  20. Graphene/fly ash geopolymeric composites as self-sensing structural materials

    Science.gov (United States)

    Saafi, Mohamed; Tang, Leung; Fung, Jason; Rahman, Mahbubur; Sillars, Fiona; Liggat, John; Zhou, Xiangming

    2014-06-01

    The reduction of graphene oxide during the processing of fly ash-based geopolymers offers a completely new way of developing low-cost multifunctional materials with significantly improved mechanical and electrical properties for civil engineering applications such as bridges, buildings and roads. In this paper, we present for the first time the self-sensing capabilities of fly ash-based geopolymeric composites containing in situ reduced graphene oxide (rGO). Geopolymeric composites with rGO concentrations of 0.0, 0.1 and 0.35% by weight were prepared and their morphology and conductivity were determined. The piezoresistive effect of the rGO-geopolymeric composites was also determined under tension and compression. The Fourier transform infrared spectroscopy (FTIR) results indicate that the rGO sheets can easily be reduced during synthesis of geopolymers due to the effect of the alkaline solution on the functional groups of GO. The scanning electron microscope (SEM) images showed that the majority of pores and voids within the geopolymers were significantly reduced due to the addition of rGO. The rGO increased the electrical conductivity of the fly ash-based rGO-geopolymeric composites from 0.77 S m-1 at 0.0 wt% to 2.38 S m-1 at 0.35 wt%. The rGO also increased the gauge factor by as much as 112% and 103% for samples subjected to tension and compression, respectively.

  1. Phylogenetic profiles reveal structural/functional determinants of TRPC3 signal-sensing antennae

    OpenAIRE

    Ko, Kyung Dae; Bhardwaj, Gaurav; Hong, Yoojin; Chang, Gue Su; Kiselyov, Kirill; van Rossum, Damian B.; Patterson, Randen L

    2009-01-01

    Biochemical assessment of channel structure/function is incredibly challenging. Developing computational tools that provide these data would enable translational research, accelerating mechanistic experimentation for the bench scientist studying ion channels. Starting with the premise that protein sequence encodes information about structure, function and evolution (SF&E), we developed a unified framework for inferring SF&E from sequence information using a knowledge-based approach. The Gesta...

  2. The Sensing Principle of FBG and Its Experimental Application in Structure Strengthening Detection

    Institute of Scientific and Technical Information of China (English)

    YUAN Hai-qing; YUAN Jun; DU Jing

    2003-01-01

    Based on the basic theory of the fiber Bragg grating sensor,a kind of stickup FBG sensor is developed,which is applied in the structure strengthening.With the experiment of the FBG senor and the common electricity sensor stuck on the reinforced structure,the result shows that the FBG sensor not only has a high performance,but also can realize the control on the spot and on the line.

  3. Effects of Short-Term Chilling Stress on the Photosystems and Chloroplast Ultrastructure in Sweet Pepper

    Institute of Scientific and Technical Information of China (English)

    LI Xin-guo; BI Yu-ping; ZHAO Shi-jie; MENG Qing-wei; HE Qi-wei; ZOU Qi

    2005-01-01

    By measuring chlorophyll fluorescence parameters, composition of fatty acids, active oxygen species and activities of some antioxidant enzymes, effects of chilling stress (4℃) in the low light (100 μmol m-2 s-1) on chilling-sensitive plants were studied. After 6 h chilling stress (4℃) in the low light, the maximal photochemical efficiency of PSⅡ (Fv/Fm) of sweet pepper leaves decreased by 35.6%, and the oxidizable P700 decreased by 60%. However, chilling stress in the dark had no effect on both of them. Unsaturation of fatty acids in thylakoid membrane was accelerated, which might be helpful to stabilize photosynthetic apparatus. Distortion and swelling of grana caused by chilling in the dark probably decreased activities of antioxidant enzymes, which resulted in the accumulation of active oxygen species. On the contrary,photooxidation might be related to the disintegration and unstacking of grana. Chilling stress induced photoinhibition of PSⅡ and PSⅠ, and active oxygen species might be one of the factors causing the decrease of the oxidizable P700. PSⅠseemed to be more sensitive to chilling stress in the low light than PSⅡ.

  4. Music chills: The eye pupil as a mirror to music's soul.

    Science.gov (United States)

    Laeng, Bruno; Eidet, Lise Mette; Sulutvedt, Unni; Panksepp, Jaak

    2016-08-01

    This study evaluated whether music-induced aesthetic "chill" responses, which typically correspond to peak emotional experiences, can be objectively monitored by degree of pupillary dilation. Participants listened to self-chosen songs versus control songs chosen by other participants. The experiment included an active condition where participants made key presses to indicate when experiencing chills and a passive condition (without key presses). Chills were reported more frequently for self-selected songs than control songs. Pupil diameter was concurrently measured by an eye-tracker while participants listened to each of the songs. Pupil size was larger within specific time-windows around the chill events, as monitored by key responses, than in comparison to pupil size observed during 'passive' song listening. In addition, there was a clear relationship between pupil diameter within the chills-related time-windows during both active and passive conditions, thus ruling out the possibility that chills-related pupil dilations were an artifact of making a manual response. These findings strongly suggest that music chills can be visible in the moment-to-moment changes in the size of pupillary responses and that a neuromodulatory role of the central norepinephrine system is thereby implicated in this phenomenon.

  5. Music chills: The eye pupil as a mirror to music's soul.

    Science.gov (United States)

    Laeng, Bruno; Eidet, Lise Mette; Sulutvedt, Unni; Panksepp, Jaak

    2016-08-01

    This study evaluated whether music-induced aesthetic "chill" responses, which typically correspond to peak emotional experiences, can be objectively monitored by degree of pupillary dilation. Participants listened to self-chosen songs versus control songs chosen by other participants. The experiment included an active condition where participants made key presses to indicate when experiencing chills and a passive condition (without key presses). Chills were reported more frequently for self-selected songs than control songs. Pupil diameter was concurrently measured by an eye-tracker while participants listened to each of the songs. Pupil size was larger within specific time-windows around the chill events, as monitored by key responses, than in comparison to pupil size observed during 'passive' song listening. In addition, there was a clear relationship between pupil diameter within the chills-related time-windows during both active and passive conditions, thus ruling out the possibility that chills-related pupil dilations were an artifact of making a manual response. These findings strongly suggest that music chills can be visible in the moment-to-moment changes in the size of pupillary responses and that a neuromodulatory role of the central norepinephrine system is thereby implicated in this phenomenon. PMID:27500655

  6. Structure-Function Relationships in the Gas-Sensing Heme-Dependent Transcription Factors RcoM and DNR

    Science.gov (United States)

    Bowman, Hannah E.

    Transition metals play an important role in many biological processes, however, they are also toxic at high concentrations. Therefore, the uptake and efflux of these metals must be tightly regulated by the cell. Bacteria have evolved a variety of pathways and regulatory systems to monitor the presence and concentration of metals in the cellular environment. A key component of those systems are transcription factors that either "sense metals" or use "metal sensors". The first class of these proteins have metals as their allosteric effector ligand. The second class of these proteins utilize transition metal containing cofactors to sense other environmental cues through the specific chemistry afforded by the cofactor. Chapter 1 reviews the current literature regarding both types of transcription factors. The focus of this work has been on two heme-containing, gas-sensing transcription factors found in bacteria, RcoM (regulator of CO metabolism) and DNR (dissimilative nitrate respiration regulator). RcoM is a CO-dependent protein found in Burkholderia xenovorans and sits upstream of the cox operon for oxidative CO metabolism. RcoM senses the presence of CO, as well as changes in redox potential, through a ligand switch process at its heme cofactor. Chapter 2 details spectroscopic characterization of several methionine mutants to identify the Fe(II) ligand trans to His 74. That study concludes that Met104 acts as the CO-replacable ligand. Met105, while not the ligand, does play an important role in reversibility of the ligand switch process. RcoM has a unique tertiary structure that combines a sensory domain and a DNA-binding domain normally found in two-component systems. Chapter 3 provides evidence that RcoM adopts a dimeric state. Further biophysical and structural characterization gives further insight into how the two domains are organized and the implications for the DNA-binding mechanism. DNR is a NO-sensing transcription factor from Pseudomonas aeruginosa and

  7. Chemical sensing by band modulation of a black phosphorus/molybdenum diselenide van der Waals hetero-structure

    Science.gov (United States)

    Feng, Zhihong; Chen, Buyun; Qian, Shuangbei; Xu, Linyan; Feng, Liefeng; Yu, Yuanyuan; Zhang, Rui; Chen, Jiancui; Li, Qianqian; Li, Quanning; Sun, Chongling; Zhang, Hao; Liu, Jing; Pang, Wei; Zhang, Daihua

    2016-09-01

    We report on a new chemical sensor based on black phosphorus/molybdenum diselenide van der Waals hetero-junctions. Due to the atomically thin nature of two-dimensional (2D) materials, surface adsorption of gas molecules can effectively modulate the band alignment at the junction interface, making the device a highly sensitive detector for chemical adsorptions. Compared to sensors made of homogeneous nanomaterials, the hetero-junction demonstrates considerably lower detection limit and higher sensitivity toward nitrogen dioxide. Kelvin probe force microscopy and finite element simulations have provided experimental and theoretical explanations for the enhanced performance, proving that chemical adsorption can induce significant changes in band alignment and carrier transport behaviors. The study demonstrates the potential of van der Waals hetero-junction as a new platform for sensing applications, and provides more insights into the interaction between gaseous molecules and 2D hetero-structures.

  8. Physiological and Biochemical Mechanisms of Seed Priming-Induced Chilling Tolerance in Rice Cultivars.

    Science.gov (United States)

    Hussain, Saddam; Khan, Fahad; Hussain, Hafiz A; Nie, Lixiao

    2016-01-01

    Rice belongs to tropical and subtropical environments and is extremely sensitive to chilling stress particularly during emergence and early stages of seedling development. Seed priming can be a good approach to enhance rice germination and stand establishment under chilling stress. The present study examined the role of different seed priming techniques viz., hydropriming, osmopriming, redox priming, chemical priming, and hormonal priming, in enhancing the chilling tolerance in rice. The most effective reagents and their pre-optimized concentrations based on preliminary experiments were used in this study. Two different rice cultivars were sown under chilling stress (18°C) and normal temperatures (28°C) in separate growth chambers. A non-primed control treatment was also maintained for comparison. Chilling stress caused erratic and delayed germination, poor seedling growth, reduced starch metabolism, and lower respiration rate, while higher lipid peroxidation and hydrogen peroxide accumulation in rice seedlings of both cultivars. Nevertheless, all the seed priming treatments effectively alleviated the negative effects of chilling stress. In addition, seed priming treatments triggered the activities of superoxide dismutase, peroxidase, and catalase, and enhanced the accumulations of glutathione and free proline in rice seedlings, which suggests that these measures help prevent the rice seedlings from chilling induced oxidative stress. Chemical priming with selenium and hormonal priming with salicylic acid remained more effective treatments for both rice cultivars under chilling stress than all other priming treatments. The better performance and greater tolerance of primed rice seedlings was associated with enhanced starch metabolism, high respiration rate, lower lipid peroxidation, and strong antioxidative defense system under chilling stress. PMID:26904078

  9. "On-off" thermoresponsive coating agent containing salicylic acid applied to maize seeds for chilling tolerance.

    Directory of Open Access Journals (Sweden)

    Yajing Guan

    Full Text Available Chilling stress is an important constraint for maize seed establishment in the field. In this study, a type of "on-off" thermoresponsive coating agent containing poly (N-isopropylacrylamide-co-butylmethacrylate (Abbr. P(NIPAm-co-BMA hydrogel was developed to improve the chilling tolerance of coated maize seed. The P(NIPAm-co-BMA hydrogel was synthesized by free-radical polymerization of N-isopropylacrylamide (NIPAm and butylmethacrylate (BMA. Salicylic acid (SA was loaded in the hydrogel as the chilling resistance agent. SA-loaded P(NIPAm-co-BMA was used for seed film-coating of two maize varieties, Huang C (HC, chilling-tolerant and Mo17 (chilling-sensitive, to investigate the coated seed germination and seedling growth status under chilling stress. The results showed that the hydrogel obtained a phase transition temperature near 12°C with a NIPAM to MBA weight ratio of 1: 0.1988 (w/w. The temperature of 12°C was considered the "on-off" temperature for chilling-resistant agent release; the SA was released from the hydrogel more rapidly at external temperatures below 12°C than above 12°C. In addition, when seedlings of both maize varieties suffered a short chilling stress (5°C, higher concentrations of SA-loaded hydrogel resulted in increased germination energy, germination percentage, germination index, root length, shoot height, dry weight of roots and shoots and protective enzyme activities and a decreased malondialdehyde content in coated maize seeds compared to single SA treatments. The majority of these physiological and biochemical parameters achieved significant levels compared with the control. Therefore, SA-loaded P(NIPAm-co-BMA, a nontoxic thermoresponsive hydrogel, can be used as an effective material for chilling tolerance in film-coated maize seeds.

  10. "On-off" thermoresponsive coating agent containing salicylic acid applied to maize seeds for chilling tolerance.

    Science.gov (United States)

    Guan, Yajing; Li, Zhan; He, Fei; Huang, Yutao; Song, Wenjian; Hu, Jin

    2015-01-01

    Chilling stress is an important constraint for maize seed establishment in the field. In this study, a type of "on-off" thermoresponsive coating agent containing poly (N-isopropylacrylamide-co-butylmethacrylate) (Abbr. P(NIPAm-co-BMA)) hydrogel was developed to improve the chilling tolerance of coated maize seed. The P(NIPAm-co-BMA) hydrogel was synthesized by free-radical polymerization of N-isopropylacrylamide (NIPAm) and butylmethacrylate (BMA). Salicylic acid (SA) was loaded in the hydrogel as the chilling resistance agent. SA-loaded P(NIPAm-co-BMA) was used for seed film-coating of two maize varieties, Huang C (HC, chilling-tolerant) and Mo17 (chilling-sensitive), to investigate the coated seed germination and seedling growth status under chilling stress. The results showed that the hydrogel obtained a phase transition temperature near 12°C with a NIPAM to MBA weight ratio of 1: 0.1988 (w/w). The temperature of 12°C was considered the "on-off" temperature for chilling-resistant agent release; the SA was released from the hydrogel more rapidly at external temperatures below 12°C than above 12°C. In addition, when seedlings of both maize varieties suffered a short chilling stress (5°C), higher concentrations of SA-loaded hydrogel resulted in increased germination energy, germination percentage, germination index, root length, shoot height, dry weight of roots and shoots and protective enzyme activities and a decreased malondialdehyde content in coated maize seeds compared to single SA treatments. The majority of these physiological and biochemical parameters achieved significant levels compared with the control. Therefore, SA-loaded P(NIPAm-co-BMA), a nontoxic thermoresponsive hydrogel, can be used as an effective material for chilling tolerance in film-coated maize seeds. PMID:25807522

  11. Physiological and biochemical mechanisms of seed priming-induced chilling tolerance in rice cultivars

    Directory of Open Access Journals (Sweden)

    Saddam eHussain

    2016-02-01

    Full Text Available Rice belongs to tropical and subtropical environments and is extremely sensitive to chilling stress particularly during emergence and early stages of seedling development. Seed priming can be a good approach to enhance rice germination and stand establishment under chilling stress. The present study examined the role of different seed priming techniques viz., hydropriming, osmopriming, redox priming, chemical priming, and hormonal priming, in enhancing the chilling tolerance in rice. The most effective reagents and their pre-optimized concentrations based on preliminary experiments were used in this study. Two different rice cultivars were sown under chilling stress (18˚C and normal temperatures (28˚C in separate growth chambers. A non-primed control treatment was also maintained for comparison. Chilling stress caused erratic and delayed germination, poor seedling growth, reduced starch metabolism and lower respiration rate, while higher lipid peroxidation and hydrogen peroxide accumulation in rice seedlings of both cultivars. Nevertheless, all the seed priming treatments effectively alleviated the negative effects of chilling stress. In addition, seed priming treatments triggered the activities of superoxide dismutase, peroxidase, and catalase, and enhanced the accumulations of glutathione and free proline in rice seedlings, which suggests that these measures help prevent the rice seedlings from chilling induced oxidative stress. Chemical priming with selenium and hormonal priming with salicylic acid remained more effective treatments for both rice cultivars under chilling stress than all other priming treatments. The better performance and greater tolerance of primed rice seedlings was associated with enhanced starch metabolism, high respiration rate, lower lipid peroxidation, and strong antioxidative defense system under chilling stress.

  12. On the detection of adobe buried archaeological structures using multiscale remote sensing techniques : Piramide Naranja in Cahuachi (Peru)

    Science.gov (United States)

    Masini, N.; Rizzo, E.; Lasaponara, R.; Orefici, G.

    2009-04-01

    The detection of buried adobe structures is a crucial issue for the remote sensing (ground, aerial and satellite) applied to archaeology for the widespread of sun-dried earth as building material in several ancient civilizations in Central and Southern America, Middle East and North Africa. Moreover it is complex, due to the subtle contrast existing between the archaeological features and the surrounding, especially in arid setting, as in the case of the well know Nazca Ceremonial Centre of Cahuachi, located in the desert of Nazca (Southern Peru) . During the last two decades of excavations adobe monuments dating back from the 6th century B.C. to the 4th century A.D have been highlighted by the Centro de Estudios Arqueológicos Precolombinos (CEAP), an italian-peruvian mission directed by Giuseppe Orefici. Actually, the archaeologists are excavating and restoring the core of the Ceremonial centre where is located a great pyramid (kown as Gran Piramide). Beginning from 2007 the two institutes of CNR, IMAA and IBAM, have been involved by CEAP, in order to provide a scientific and technological support for the archaeological research. Therefore, a multi-scale approach based on the integration of aerial and satellite remote sensing with geophysical techniques was employed in order to provide data useful for archaeological excavations. The abstract refers to the last investigations performed on a mound, known as "Piramide Naranja", during the 2008. The processing of an aerial imagery time series and two QuickBird satellite images acquired in 2002 and 2005, allowed for identifying some features related to shallow and buried structures. Such features were verified by means of geophysical prospections, performed by using the magnetometric method which observed changes in the magnetic field within the first few metres beneath the subsurface detecting buried walls and anomalies linked to ceramic deposits referable to possible tombs. Finally, the integration of all data

  13. Extracellular calcium-sensing receptor: structural and functional features and association with diseases

    Directory of Open Access Journals (Sweden)

    O.M. Hauache

    2001-05-01

    Full Text Available The recently cloned extracellular calcium-sensing receptor (CaR is a G protein-coupled receptor that plays an essential role in the regulation of extracellular calcium homeostasis. This receptor is expressed in all tissues related to this control (parathyroid glands, thyroid C-cells, kidneys, intestine and bones and also in tissues with apparently no role in the maintenance of extracellular calcium levels, such as brain, skin and pancreas. The CaR amino acid sequence is compatible with three major domains: a long and hydrophilic aminoterminal extracellular domain, where most of the activating and inactivating mutations described to date are located and where the dimerization process occurs, and the agonist-binding site is located, a hydrophobic transmembrane domain involved in the signal transduction mechanism from the extracellular domain to its respective G protein, and a carboxyterminal intracellular tail, with a well-established role for cell surface CaR expression and for signal transduction. CaR cloning was immediately followed by the association of genetic human diseases with inactivating and activating CaR mutations: familial hypocalciuric hypercalcemia and neonatal severe hyperparathyroidism are caused by CaR-inactivating mutations, whereas autosomal dominant hypoparathyroidism is secondary to CaR-activating mutations. Finally, we will comment on the development of drugs that modulate CaR function by either activating (calcimimetic drugs or antagonizing it (calcilytic drugs, and on their potential therapeutic implications, such as medical control of specific cases of primary and uremic hyperparathyroidism with calcimimetic drugs and a potential treatment for osteoporosis with a calcilytic drug.

  14. Building Selectivity for NO Sensing in a NOx Mixture with Sonochemically Prepared CuO Structures

    Directory of Open Access Journals (Sweden)

    Max R. Mullen

    2015-12-01

    Full Text Available Several technologies are available for decreasing nitrogen oxide (NOx emissions from combustion sources, including selective catalytic reduction methods. In this process, ammonia reacts with nitric oxide (NO and nitrogen dioxide (NO2. As the stoichiometry of the two reactions is different, electrochemical sensor systems that can distinguish between NO and NO2 in a mixture of these two gases are of interest. Since NO and NO2 can be brought to equilibrium, depending on the temperature and the surfaces that they are in contact with, the detection of NO and NO2 independently is a difficult problem and has not been solved to date. In this study, we explore a high surface area sonochemically prepared CuO as the resistive sensing medium. CuO is a poor catalyst for NOx equilibration, and requires temperatures of 500 C to bring about equilibration. Thus, at 300 C, NO and NO2 retain their levels after interaction with CuO surface. In addition, NO adsorbs more strongly on the CuO over NO2. Using these two concepts, we can detect NO with minimal interference from NO2, if the latter gas concentration does not exceed 20% in a NOx mixture over a range of 100–800 ppm. Since this range constitutes most of the range of total NOx concentrations in diesel and other lean burn engines, this sensor should find application in selective detection of NO in this combustion application. A limitation of this sensor is the interference with CO, but with combustion in excess air, this problem should be alleviated.

  15. A study of structural lineaments in Pantanal (Brazil using remote sensing data

    Directory of Open Access Journals (Sweden)

    ANTONIO C. PARANHOS FILHO

    2013-09-01

    Full Text Available This paper presents a study of the structural lineaments of the Pantanal extracted visually from satellite images (CBERS-2B satellite, Wide Field Imager sensor, a free image available in INTERNET and a comparison with the structural lineaments of Precambrian and Paleozoic rocks surrounding the Cenozoic Pantanal Basin. Using a free software for satellite image analysis, the photointerpretation showed that the NS, NE and NW directions observed on the Pantanal satellite images are the same recorded in the older rocks surrounding the basin, suggesting reactivation of these basement structural directions during the Quaternary. So the Pantanal Basin has an active tectonics and its evolution seems to be linked to changes that occurred during the Andean subduction.

  16. Standardization in fiber-optic sensing for structural safety: activities in the ISHMII and IEC

    Science.gov (United States)

    Habel, Wolfgang R.; Krebber, K.; Daum, W.

    2015-03-01

    Fiber-optic sensors are increasingly established in the sensor market. Their advantages have unquestionably been verified by numerous demonstrations to enhance the operational performance of aged structures or to monitor the structural behavior of safety-relevant structures or their components. However, there are some barriers in use due to a lack of extensive standardization of fiber-optic sensors. This leads very often to restraints in the user's community. The paper shows the status in international standardization of fiber-optic sensors as well as current activities in leading institutions such as IEC and ISHMII and others with the purpose of providing relevant standards for a broader use of selected fiber-optic sensor technologies.

  17. A highly sensitive pressure sensor using a double-layered graphene structure for tactile sensing.

    Science.gov (United States)

    Chun, Sungwoo; Kim, Youngjun; Oh, Hyeong-Sik; Bae, Giyeol; Park, Wanjun

    2015-07-21

    In this paper, we propose a graphene sensor using two separated single-layered graphenes on a flexible substrate for use as a pressure sensor, such as for soft electronics. The working pressure corresponds to the range in which human perception recognizes surface morphologies. A specific design of the sensor structure drives the piezoresistive character due to the contact resistance between two graphene layers and the electromechanical properties of graphene itself. Accordingly, sensitivity in resistance change is given by two modes for low pressure (-0.24 kPa(-1)) and high pressure (0.039 kPa(-1)) with a crossover pressure (700 Pa). This sensor can detect infinitesimal pressure as low as 0.3 Pa with uniformly applied vertical force. With the attachment of the artificial fingerprint structure (AFPS) on the sensor, the detection ability for both the locally generated shear force and actual human touch confirms recognition of the surface morphology constructed by periodic structures.

  18. A multiphysics and multiscale model for low frequency electromagnetic direct-chill casting

    Science.gov (United States)

    Košnik, N.; Guštin, A. Z.; Mavrič, B.; Šarler, B.

    2016-03-01

    Simulation and control of macrosegregation, deformation and grain size in low frequency electromagnetic (EM) direct-chill casting (LFEMC) is important for downstream processing. Respectively, a multiphysics and multiscale model is developed for solution of Lorentz force, temperature, velocity, concentration, deformation and grain structure of LFEMC processed aluminum alloys, with focus on axisymmetric billets. The mixture equations with lever rule, linearized phase diagram, and stationary thermoelastic solid phase are assumed, together with EM induction equation for the field imposed by the coil. Explicit diffuse approximate meshless solution procedure [1] is used for solving the EM field, and the explicit local radial basis function collocation method [2] is used for solving the coupled transport phenomena and thermomechanics fields. Pressure-velocity coupling is performed by the fractional step method [3]. The point automata method with modified KGT model is used to estimate the grain structure [4] in a post-processing mode. Thermal, mechanical, EM and grain structure outcomes of the model are demonstrated. A systematic study of the complicated influences of the process parameters can be investigated by the model, including intensity and frequency of the electromagnetic field. The meshless solution framework, with the implemented simplest physical models, will be further extended by including more sophisticated microsegregation and grain structure models, as well as a more realistic solid and solid-liquid phase rheology.

  19. Integrated Quality Assurance of Chilled Food Fish at Sea

    DEFF Research Database (Denmark)

    Frederiksen, Marco Thorup; Olsen, Karsten Bæk; Popescu, Valeriu

    1997-01-01

    The aim of the IQAS project is to improve the quality of fresh fish (white fish and flat fish) landed by the Community vessels significantly and to increase the proportion of the fish caught used for food purposes, as well as to improve the on-board working conditions. This will be achieved by......, container labelling and data storage system has been developed to specify the quality of the fish to the buyer at the point of sale by reference to the actual time/temperature history of the fish prior to the sale and to the measurements of length and weight...... specifying and developing safe, efficient, mechanized on-board handling systems enabling the catch to be sorted, gutted, bled, characterized for length and weight, prepared quickly and correctly for rapid chilling and to be stored in appropriate, labelled containers at 0°C until sold. A monitoring, measuring...

  20. Respiratory Response of Dormant Nectarine Floral Buds on Chilling Deficiency

    Institute of Scientific and Technical Information of China (English)

    TAN Yue; GAO Dong-sheng; LI Ling; CHEN Xiu-de; XU Ai-hong

    2010-01-01

    Changes in main biochemical respiratory pathways in dormant nectarine floral buds were studied with nectarine trees (Prunus persica.var,nectariana cv.Shuguang) in order to determine the function of respiration in dormancy release.Oxygen-electrode system and respiratory inhibitors were used to measure total respiratory rates and rates of respiratory pathways.Results showed that chilling deficiency blocked the transition of respiratory mode,and made buds stay in a state of high level pentose phosphate pathway (PPP) and low level tricarboxylic acid cycle (TCA).The decline of PPP and activation of TCA occurred synchronously with the release of dormancy.In addition,the inhibition of PPP stimulated a respiration increase related with TCA.It could be concluded that the function of PPP activation in dormancy release might be limited and PPP declination inducing TCA activation might be part of respiration mode transition mechanism during bud sprouting.

  1. Two-Pipe Chilled Beam System for Both Cooling and Heating of Office Buildings

    OpenAIRE

    Afshari, Alireza; Gordnorouzi, Rouzbeh; Hultmark, Göran; Bergsøe, Niels Christian

    2013-01-01

    Simulations were performed to compare a conventional 4-pipe chilled beam system and a 2-pipe chilled beam system. The objective was to establish requirements, possibilities and limitations for a well-functioning 2-pipe chilled beam system for both cooling and heating of office buildings. The building model had a net volume of 3669 m3, (L*B: 25.5m*11.5 m) and net ceiling height of 2.55 m. The building model was assumed to consist of 78 office rooms, 6 meeting rooms and 5 corridors with a 50% o...

  2. Analysis and Evaluation Indicator Selection of Chilling Tolerance of Different Cotton Genotypes

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    [Objectivc] This study aimed to investigate the chilling tolerance of seedlings of different cotton genotypes and screen appropriate indicators for assess- ing chilling tolerance, to establish reliable mathematical evaluation model for chilling tolerance of cotton, thus providing theoretical basis for breeding and promoting new chilling-tolerant cotton germplasms and large-scale evaluation of chilling tolerance of cotton varieties. [Method] Fifteen cotton varieties (lines) were used as experimental materials. The photosynthetic gas exchange parameters, chlorophyll fluorescence ki- netic parameters, chlorophyll content, relative soluble sugar content, malonaldehyde content, relative proiine content, relative conductivity and other 12 physiological indi- cators of seedling leaves under low temperature treatment (5 ℃, 12 h) and recovery treatment (25 ℃. 24 h) were determined; based on the chilling tolerance coefficient (CTC) of various individual indicators, the comprehensive evaluation of chilling toler- ance was conducled by using principal component analysis, hierarchical cluster anal- ysis and stepwise regression analysis. [Result] The results showed that the 12 indi- vidual physiological indicators could be classified into 7 independent comprehensive components by principal component analysis; 15 cotton varieties (lines) were clus- tered into three categories by using membership function method and hierarchical cluster analysis; the mathematical model for evaluating chilling tolerance of cotton seedlings was established: D =0.275 -0.244Fo1 +0.206Fv/Fm1+0.326g,%-0.056SS + 0.225MDA+O.O38REC (FF=0.995), and the evaluation accuracy of the equation was higher than 94.25%,0. Six identification indicators closely related to chilling tolerance were screened, including Fo,, Fv/Fm1, Seedling leaves of cotton varieties (lines) gs2, SS, MDA, and REC. [Conclusion] with high chilling tolerance are less dam- aged under low temperature stress, and are able to maintain

  3. Prediction of Pressure Drop in Chilled Water Piping System Using Theoretical and CFD Analysis

    Directory of Open Access Journals (Sweden)

    Shirish P. Patil

    2013-08-01

    Full Text Available In the present study, three dimensional models of chilled water piping system is created using design modeler of Ansys-13. Ansys-13 fluent is used to analyses flow through chilled water pipe for pressure drop prediction. Karman-Prandtl equation is used for defining velocity profile of turbulent flow with the help of user defined function. Result obtained from CFD analysis is compared with results of 3K, 2K, ISHARE and Carrier equivalent length methods. Statistical analysis of performance based relative error has been carried out and based on that optimum analytical method for pressure drop prediction in chilled water piping is suggested.

  4. Characterizing the multi–scale spatial structure of remotely sensed evapotranspiration with information theory

    Science.gov (United States)

    A more thorough understanding of the multi-scale spatial structure of land surface heterogeneity will enhance understanding of the relationships and feedbacks between land surface conditions,mass and energy exchanges between the surface and the atmosphere, and regional meteorological and climatologi...

  5. Structural Relationships among E-Learners' Sense of Presence, Usage, Flow, Satisfaction, and Persistence

    Science.gov (United States)

    Joo, Young Ju; Joung, Sunyoung; Kim, Eun Kyung

    2013-01-01

    This study aimed to investigate the structural relationships among teaching presence, cognitive presence, usage, learning flow, satisfaction, and learning persistence in corporate e-learners. The research participants were 462 e-learners registered for cyber-lectures through an electronics company in South Korea. The extrinsic variables were sense…

  6. Sedimentary structures and facies interpretation of some molasse deposits : Sense- Schwarzwasser area, Canton Bern, Switzerland

    NARCIS (Netherlands)

    Linden, W.J.M. van der

    1963-01-01

    Burdigalian sand· and siltstones, belonging to the Upper Marine Molasse, have been studied in the Swiss "Mittel]and", to get an insight into the rela· tionships between primary sedimentary structures, their genesis and facies. To obtain information on the conditions, prevailing during the deposition

  7. A Bio-Inspired Two-Layer Sensing Structure of Polypeptide and Multiple-Walled Carbon Nanotube to Sense Small Molecular Gases

    Directory of Open Access Journals (Sweden)

    Li-Chun Wang

    2015-03-01

    Full Text Available In this paper, we propose a bio-inspired, two-layer, multiple-walled carbon nanotube (MWCNT-polypeptide composite sensing device. The MWCNT serves as a responsive and conductive layer, and the nonselective polypeptide (40 mer coating the top of the MWCNT acts as a filter into which small molecular gases pass. Instead of using selective peptides to sense specific odorants, we propose using nonselective, peptide-based sensors to monitor various types of volatile organic compounds. In this study, depending on gas interaction and molecular sizes, the randomly selected polypeptide enabled the recognition of certain polar volatile chemical vapors, such as amines, and the improved discernment of low-concentration gases. The results of our investigation demonstrated that the polypeptide-coated sensors can detect ammonia at a level of several hundred ppm and barely responded to triethylamine.

  8. Data Structures and Algorithms for Graph Based Remote Sensed Image Content Storage and Retrieval

    Energy Technology Data Exchange (ETDEWEB)

    Grant, C W

    2004-06-24

    The Image Content Engine (ICE) project at Lawrence Livermore National Laboratory (LLNL) extracts, stores and allows queries of image content on multiple levels. ICE is designed for multiple application domains. The domain explored in this work is aerial and satellite surveillance imagery. The highest level of semantic information used in ICE is graph based. After objects are detected and classified, they are grouped based in their interrelations. The graph representing a locally related set of objects is called a 'graphlet'. Graphlets are interconnected into a larger graph which covers an entire set of images. Queries based on graph properties are notoriously difficult due the inherent complexity of the graph isomorphism and sub-graph isomorphism problems. ICE exploits limitations in graph and query structure and uses a set of auxiliary data structures to quickly process a useful set of graph based queries. These queries could not be processed using semantically lower level (tile and object based) queries.

  9. Sensing characteristics of plasmonic structure based on transferring process of polystyrene nano-beads

    Science.gov (United States)

    Kim, Doo Gun; Hwang, Jeongwoo; Kim, Seon Hoon; Ki, Hyun Chul; Kim, Tae Un; Shin, Jae Cheol; Jeong, Dae-Cheol; Jeon, Seungwon; Kim, Hong-Seung; Choi, Young-Wan

    2016-04-01

    We analyzed and demonstrated the double layered metallic nano-structures using polystyrene lift-off process on the conventional surface plasmon resonance (SPR) sensor to enhance the sensitivity of an SPR surface. The double layered plasmonic structures are optimized using the three-dimensional finite-difference time-domain method for the width, thickness, and period of the polystyrene beads. The thickness of the metal film and the metallic nano-hole is 20 and 20 nm in the 305 nm wide nano-hole size, respectively. The double layered metallic nano-structures are fabricated with monolayer polystyrene beads of chloromethyl latex 4% w/v 0.4 μm. The sensitivities of the conventional SPR sensor and the double layered plasmonic sensor are obtained to 42.2 and 60 degree/RIU, respectively. The SPR devices are also applied to the lead ion sensor. The resonance shifts of SPR sensors with and without a poly(vinyl chloride) membrane are 1328 RU and 788 RU from 10-5 M to 10-2 M concentration, respectively.

  10. Fluid-structure interaction-based biomechanical perception model for tactile sensing.

    Directory of Open Access Journals (Sweden)

    Zheng Wang

    Full Text Available The reproduced tactile sensation of haptic interfaces usually selectively reproduces a certain object attribute, such as the object's material reflected by vibration and its surface shape by a pneumatic nozzle array. Tactile biomechanics investigates the relation between responses to an external load stimulus and tactile perception and guides the design of haptic interface devices via a tactile mechanism. Focusing on the pneumatic haptic interface, we established a fluid-structure interaction-based biomechanical model of responses to static and dynamic loads and conducted numerical simulation and experiments. This model provides a theoretical basis for designing haptic interfaces and reproducing tactile textures.

  11. Process for nondestructively testing with radioactive gas using a chill set sealant

    International Nuclear Information System (INIS)

    An article surface is nondestructively tested for substantially invisible surface voids by absorbing a radioactive gas thereon. The adsorbed radioactive gas is disproportionately retained on those surfaces presented by the substantially invisible surface voids as compared to the remaining surfaces of the article contacted by the radioactive gas. The radiation released by the radioactive gas remaining adsorbed is used to identify the substantially invisible voids. To immobilize the radioactive gas adjacent or within the surface voids, a sealant composition is provided which is capable of being chill set. The temperatures of the article surface to be tested and the sealant composition are then related so that the article surface is at a temperature below the chill set temperature of the sealant composition and the sealant composition is at a temperature above its chill set temperature. The article portion to be tested is then coated with sealant composition to form a chill set coating thereon of substantially uniform thickness. (U.S.)

  12. Human response to individually controlled micro environment generated with localized chilled beam

    DEFF Research Database (Denmark)

    Uth, Simon C.; Nygaard, Linette; Bolashikov, Zhecho Dimitrov;

    2014-01-01

    Indoor environment in a single-office room created by a localised chilled beam with individual control of the primary air flow was studied. Response of 24 human subjects when exposed to the environment generated by the chilled beam was collected via questionnaires under a 2-hour exposure including...... different work tasks at three locations in the room. Response of the subjects to the environment generated with a chilled ceiling combined with mixing air distribution was used for comparison. The air temperature in the room was kept at 26 or 28 °C. Results show no significant difference in the overall and...... local thermal sensation reported by the subjects with the two systems. Both systems were equally acceptable. At 26°C the individual control of the localised chilled beam lead to higher acceptability of the work environment. At 28°C the acceptability decreased with the two systems. It was not acceptable...

  13. Two-Pipe Chilled Beam System for Both Cooling and Heating of Office Buildings

    DEFF Research Database (Denmark)

    Afshari, Alireza; Gordnorouzi, Rouzbeh; Hultmark, Göran;

    2013-01-01

    . The building model had a net volume of 3669 m3, (L*B: 25.5m*11.5 m) and net ceiling height of 2.55 m. The building model was assumed to consist of 78 office rooms, 6 meeting rooms and 5 corridors with a 50% occupancy. Simulations were executed using Bsim, an energy simulation program, to calculate the energy...... advantage of renewable energy. The results showed that the energy consumption was 3% less in the 2-pipe chilled beam system in comparison with the conventional 4-pipe system when moving cooled and heated water through the building, transferring the energy to where it is needed. Using free cooling (taking......Simulations were performed to compare a conventional 4-pipe chilled beam system and a 2-pipe chilled beam system. The objective was to establish requirements, possibilities and limitations for a well-functioning 2-pipe chilled beam system for both cooling and heating of office buildings...

  14. Neutrino oscillation provides clues to dark matter and signals from the chilled universe

    CERN Multimedia

    2006-01-01

    The new verification that oscillations exists and neutrinos have mass though not detectible easy provides the first clue to extra dimensions, dark matter, hyperspace and chilled universe acting as a platform below it. (1/2 page)

  15. Hydrazone based luminescent receptors for fluorescent sensing of Cu{sup 2+}: Structure and spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Mukherjee, Soma, E-mail: sommukh445@yahoo.co.in [Department of Environmental Science, University of Kalyani, Kalyani, Nadia, 741235 West Bengal (India); Mal, Palash [Department of Environmental Science, University of Kalyani, Kalyani, Nadia, 741235 West Bengal (India); Stoeckli-Evans, Helen [Institute of Physics, University of Neuchâtel, rue Emile-Argand 11, CH-2000 Neuchâtel (Switzerland)

    2014-11-15

    Two new luminescent hydrazones, HL1 and HL2 were investigated for selective and sensitive fluorescent recognition of Cu{sup 2+} in aqueous medium (CH{sub 3}CN/H{sub 2}O (1:4, v/v) solvent system) with a 1:1 binding stoichiometry. The emission peak of HL (λ{sub em}=405 nm), undergoes significant quenching upon complexation with Cu{sup 2+}. The quantum yields for the receptors and in situ formed Cu{sup 2+} complexes were determined. The absorption ratiometric analysis was carried out in presence of various metal ions to confirm the selectivity of the receptors towards Cu{sup 2+}. They were able to detect Cu{sup 2+} with a ∼0.9 µM detection limit as indicated by fluorimetric measurements. The molecular structures of the receptors were determined by single crystal X-ray diffraction analysis. - Highlights: • Small molecule luminescent hydrazones were developed for recognition of Cu{sup 2+}. • Selectivity and sensitivity were studied spectroscopically in aqueous medium. • Binding stoichiometry, association constant, and quantum yields were calculated. • Receptors have low detection limit for Cu{sup 2+}. • Crystal structures of the receptors were solved by X-ray diffractometry.

  16. The fabrication of nanochain structure of gold nanoparticles and its application in ractopamine sensing.

    Science.gov (United States)

    Duan, Jiahua; He, Dawei; Wang, Wenshuo; Liu, Yongchuan; Wu, Hongpeng; Wang, Yongsheng; Fu, Ming; Li, Shulei

    2013-10-15

    The illegal food additives including ractopamine and melamine throw a serious threat to human health. In this paper, the ractopamine and melamine were first used to form the nanochain structure of citrate-stabilized gold nanoparticles (AuNPs) with a convenient and inexpensive method. The fabricated nanochain structure consisting of several AuNPs was characterized by Scanning Electron Microscopy. A new longitudinal surface plasma resonance, which could be adjusted from visible to near infrared range, was observed in absorption spectra due to the aggregation of AuNPs. This could be well explained by Finite Different Time Domain algorithm theoretically. As confirmed by Fourier Transform Infrared Spectroscopy, the complex formed by hydrogen-bonding interaction between melamine and ractopamine could effectively promote the aggregation of AuNPs that was useful to develop the sensitivity and selectivity for the detection of ractopamine. Hence, the plasmonic coupling phenomenon of gold nanochain could be applied in bio-assay for ractopamine through the change of solution's color and optical absorption band with naked eye or absorption spectra. The linear range was broadened to (1.23 × 10(-7)M, 1.11 × 10(-6)M) and the limit of detection was extended to 4.10 × 10(-8)M (S/N=3). More importantly, this time-saving method will be promising in rapid and selective detection of β-agonist for clinical applications. PMID:24054693

  17. High-quality molybdenum disulfide nanosheets with 3D structure for electrochemical sensing

    Science.gov (United States)

    Yin, Aiping; Wei, Xuehong; Cao, Yexia; Li, Huiqing

    2016-11-01

    An electrochemical sensor has been developed for simultaneous detection of dopamine (DA), uric acid (UA) and ascorbic acid (AA) based on pure MoS2 nanosheets modified electrode. The MoS2 nanosheets are achieved via a facile strategy, one-step pyrolysis of ammonium molybdate, thiourea and layered g-C3N4 template. Possessing hierarchical porous structure and large pore volume as well as good conductivity, MoS2 nanosheets demonstrates significantly improved electrocatalytic activity toward oxidation of AA, DA, and UA. In the coexisting system, the peak separation of AA-DA, DA-UA and AA-UA is 208.3 mV, 128.0 mV and 336.3 mV, respectively, which is much larger than for other MoS2-based catalyst. On the basis of large potential separation and high current response, selective and sensitive simultaneous determination of AA, DA, and UA was successfully accomplished by DPV, displaying a linear response from 5 to 1200 μM, from 1 to 900 μM, and from 1 to 60 μM with a detection limit (S/N = 3) of 0.82, 0.15, and 0.06 μM. This work highlights the importance of Mo-edge sites of MoS2 and hierarchical porous structure for efficient catalysis.

  18. Minimal-Sensing, Passive Force Identification Techniques for a Composite Structural Missile Component

    Directory of Open Access Journals (Sweden)

    Nick Stites

    2009-01-01

    Full Text Available Structural health monitoring systems are often limited to the use of one sensor due to cost, complexity, and weight restrictions. Therefore, there is a need to develop load and damage identification techniques that utilize only one sensor. Two passive force estimation techniques are investigated in this work. The techniques focus on either the shape or the amplitude of the magnitude of the applied force in the frequency domain. Both techniques iteratively reduce an underdetermined set of equations of motion into many overdetermined systems of equations to solve for the force estimates. The techniques are shown to locate and quantify impulsive impacts with over 97% accuracy and non-impulsive impacts with at least 87% accuracy. A filament-wound rocket motor casing is used as a test structure. Impacts not acting at a specific input degree of freedom are also accurately located depending on the distance away from the modeled input degrees of freedom, and damaging impact forces are quantified by making assumptions about the impulsive nature of the applied force.

  19. Structural Basis for Molecular Discrimination by a 3′,3′-cGAMP Sensing Riboswitch

    Directory of Open Access Journals (Sweden)

    Aiming Ren

    2015-04-01

    Full Text Available Cyclic dinucleotides are second messengers that target the adaptor STING and stimulate the innate immune response in mammals. Besides protein receptors, there are bacterial riboswitches that selectively recognize cyclic dinucleotides. We recently discovered a natural riboswitch that targets 3′,3′-cGAMP, which is distinguished from the endogenous mammalian signal 2′,3′-cGAMP by its backbone connectivity. Here, we report on structures of the aptamer domain of the 3′,3′-cGAMP riboswitch from Geobacter in the 3′,3′-cGAMP and c-di-GMP bound states. The riboswitch adopts a tuning fork-like architecture with a junctional ligand-binding pocket and different orientations of the arms are correlated with the identity of the bound cyclic dinucleotide. Subsequent biochemical experiments revealed that specificity of ligand recognition can be affected by point mutations outside of the binding pocket, which has implications for both the assignment and reengineering of riboswitches in this structural class.

  20. An integrated photogrammetric and spatial database management system for producing fully structured data using aerial and remote sensing images.

    Science.gov (United States)

    Ahmadi, Farshid Farnood; Ebadi, Hamid

    2009-01-01

    3D spatial data acquired from aerial and remote sensing images by photogrammetric techniques is one of the most accurate and economic data sources for GIS, map production, and spatial data updating. However, there are still many problems concerning storage, structuring and appropriate management of spatial data obtained using these techniques. According to the capabilities of spatial database management systems (SDBMSs); direct integration of photogrammetric and spatial database management systems can save time and cost of producing and updating digital maps. This integration is accomplished by replacing digital maps with a single spatial database. Applying spatial databases overcomes the problem of managing spatial and attributes data in a coupled approach. This management approach is one of the main problems in GISs for using map products of photogrammetric workstations. Also by the means of these integrated systems, providing structured spatial data, based on OGC (Open GIS Consortium) standards and topological relations between different feature classes, is possible at the time of feature digitizing process. In this paper, the integration of photogrammetric systems and SDBMSs is evaluated. Then, different levels of integration are described. Finally design, implementation and test of a software package called Integrated Photogrammetric and Oracle Spatial Systems (IPOSS) is presented. PMID:22574014

  1. Remote Sensing of Sonoran Desert Vegetation Structure and Phenology with Ground-Based LiDAR

    Directory of Open Access Journals (Sweden)

    Joel B. Sankey

    2014-12-01

    Full Text Available Long-term vegetation monitoring efforts have become increasingly important for understanding ecosystem response to global change. Many traditional methods for monitoring can be infrequent and limited in scope. Ground-based LiDAR is one remote sensing method that offers a clear advancement to monitor vegetation dynamics at high spatial and temporal resolution. We determined the effectiveness of LiDAR to detect intra-annual variability in vegetation structure at a long-term Sonoran Desert monitoring plot dominated by cacti, deciduous and evergreen shrubs. Monthly repeat LiDAR scans of perennial plant canopies over the course of one year had high precision. LiDAR measurements of canopy height and area were accurate with respect to total station survey measurements of individual plants. We found an increase in the number of LiDAR vegetation returns following the wet North American Monsoon season. This intra-annual variability in vegetation structure detected by LiDAR was attributable to a drought deciduous shrub Ambrosia deltoidea, whereas the evergreen shrub Larrea tridentata and cactus Opuntia engelmannii had low variability. Benefits of using LiDAR over traditional methods to census desert plants are more rapid, consistent, and cost-effective data acquisition in a high-resolution, 3-dimensional context. We conclude that repeat LiDAR measurements can be an effective method for documenting ecosystem response to desert climatology and drought over short time intervals and at detailed-local spatial scale.

  2. An Integrated Photogrammetric and Spatial Database Management System for Producing Fully Structured Data Using Aerial and Remote Sensing Images

    Directory of Open Access Journals (Sweden)

    Farshid Farnood Ahmadi

    2009-03-01

    Full Text Available 3D spatial data acquired from aerial and remote sensing images by photogrammetric techniques is one of the most accurate and economic data sources for GIS, map production, and spatial data updating. However, there are still many problems concerning storage, structuring and appropriate management of spatial data obtained using these techniques. According to the capabilities of spatial database management systems (SDBMSs; direct integration of photogrammetric and spatial database management systems can save time and cost of producing and updating digital maps. This integration is accomplished by replacing digital maps with a single spatial database. Applying spatial databases overcomes the problem of managing spatial and attributes data in a coupled approach. This management approach is one of the main problems in GISs for using map products of photogrammetric workstations. Also by the means of these integrated systems, providing structured spatial data, based on OGC (Open GIS Consortium standards and topological relations between different feature classes, is possible at the time of feature digitizing process. In this paper, the integration of photogrammetric systems and SDBMSs is evaluated. Then, different levels of integration are described. Finally design, implementation and test of a software package called Integrated Photogrammetric and Oracle Spatial Systems (IPOSS is presented.

  3. High elastic polyurethane/carbon nanotube composite laminate for structure health monitoring by gain shifting of antenna sensing element

    Science.gov (United States)

    Olejnik, Robert; Slobodian, Petr; Matyas, Jiri; Gorakh Babar, Dipak

    2016-03-01

    The composite of carbon nanotubes and polyurethane (PU) was prepared by simple filtration technique. The PU nonwoven filtration membrane was prepared by electrospinning. A layer of carbon nanotubes was prepared by vacuum filtration on the surface of PU membrane. The resulting composite was subsequently placed on highly elastic polyurethane substrate. The contribution shows an efficient method of preparing the sensing element for monitoring the state of strain of loaded structures by using highly elastic polyurethane / carbon nanotubes composite. This sensor has been involved as passive antenna with stable resonance frequency of 650 MHz. When it is get deformed in the range from 0 to 3.5% the sensor gain was changing from -39 dB to - 19.45 dB. But if it is get deformed by 15% and again measured strain from 0 to 3.5%, sensor gain was changing from -33 dB to -12.3 dB, which clearly indicates the damage of structure.

  4. Effect of heat shock on the chilling sensitivity of trichomes and petioles of African violet (Saintpaulia ionantha).

    Science.gov (United States)

    Saltveit, Mikal E.; Hepler, Peter K.

    2004-05-01

    Chilling at 6 degrees C caused an immediate cessation of protoplasmic streaming in trichomes from African violets (Saintpaulia ionantha), and a slower aggregation of chloroplasts in the cells. Streaming slowly recovered upon warming to 20 degrees C, reaching fairly stable rates after 4, 15, 25 and 35 min for tissue chilled for 2 min and for 2, 14 and 24 h, respectively. The rate of ion leakage from excised petioles into an isotonic 0.2 M mannitol solution increased after 12 h of chilling and reached a maximum after 3 days of chilling. A heat shock at 45 degrees C for 6 min reduced chilling-induced rates of ion leakage from excised 1-cm petiole segments by over 50%, namely to levels near that from non-chilled control tissue. Heat-shock treatments themselves had no effect on the rate of ion leakage from non-chilled petiole segments. Protoplasmic streaming was stopped by 1 min of heat shock at 45 degrees C, but slowly recovered to normal levels after about 30 min Chloroplasts aggregation was prevented by a 1 or 2 min 45 degrees C heat-shock treatment administered 1.5 h before chilling, but heat-shock treatments up to 6 min only slightly delayed the reduction in protoplasmic streaming caused by chilling. Tradescantia virginiana did not exhibit symptoms associated with chilling injury in sensitive species (i.e. cessation of protoplasmic streaming in stamen hairs and increased ion leakage from leaf tissue). PMID:15086815

  5. Self-optimizing Control of Cooling Tower for Efficient Operation of Chilled Water Systems

    OpenAIRE

    Li, Xiao; Li, Yaoyu; Seem, John E.; Li, Pengfei

    2012-01-01

    The chilled-water systems, mainly consisting of electric chillers and cooling towers, are crucial for the ventilating and air conditioning systems in commercial buildings. Energy efficient operation of such systems is thus important for the energy saving of commercial buildings. This paper presents an extremum seeking control (ESC) scheme for energy efficient operation of the chilled-water system, and presents a Modelica based dynamic simulation model for demonstrating the effectiveness of th...

  6. The effect of lethal doses of X-rays on chilled and thyroidectomized animals

    Energy Technology Data Exchange (ETDEWEB)

    Hempelmann, L.H.; Trujillo, T.T.; Knowlton, N.P. Jr.

    1949-04-19

    The chilling of animals has been shown to offer some protection from the lethal effects of radiation. An effort has been made to extend the study of the effects of chilling on the lethal effects of x radiation and to determine whether or not the lowering of the basal metabolic rate by thyroidectomy will give similar protection. Five experiments were carried out using mice and rats as the experimental animals.

  7. Effect of LaCI3 on the chilling tolerance of rice seedlings

    Institute of Scientific and Technical Information of China (English)

    LIMeiru; LIUHongxian; WANGYirou

    1997-01-01

    The rice variety Tesanai 2 is susceptible to chilling. Exposure of the seedlings grown at 28±1℃ and under a photo flux density(PFD) of 30 μmol/m2s to 1℃ and under a PFD of 150μmol/m2s for 2 d caused a physiological disorder called chilling injury which reduced the survival rate to 50%.

  8. Exploring Aesthetic Chill Parameters and their Associations with Demographic, Lifestyle and Personality Variables

    OpenAIRE

    Hobbel, Sabine Hobbel

    2010-01-01

    This dissertation reviews the literature on individual differences associated with the experience of Aesthetic Chills, and reports a large questionnaire study, completed by 46 international students. Ordinal logistic regressions confirmed previously reported significant and positive relations between Openness and the frequency of Aesthetic Chills in poetry and music (McCrae 2007; Kunkel, Pramstaller, Grant, & von Georgi, 2008). Prior reported correlations between the frequency of Aesthetic Ch...

  9. Preparation and characterization of microparticles of piroxicam by spray drying and spray chilling methods

    OpenAIRE

    Dixit, M.; Kini, A.G.; Kulkarni, P.K.

    2010-01-01

    Piroxicam, an anti-inflammatory drug, exhibits poor water solubility and flow properties, poor dissolution and poor wetting. Consequently, the aim of this study was to improve the dissolution of piroxicam. Microparticles containing piroxicam were produced by spray drying, using isopropyl alcohol and water in the ratio of 40:60 v/v as solvent system, and spray chilling technology by melting the drug and chilling it with a pneumatic nozzle to enhance dissolution rate. The prepared formulations ...

  10. Cytochromes c': Structure, Reactivity and Relevance to Haem-Based Gas Sensing.

    Science.gov (United States)

    Hough, Michael A; Andrew, Colin R

    2015-01-01

    Cytochromes c' are a group of class IIa cytochromes with pentacoordinate haem centres and are found in photosynthetic, denitrifying and methanotrophic bacteria. Their function remains unclear, although roles in nitric oxide (NO) trafficking during denitrification or in cellular defence against nitrosoative stress have been proposed. Cytochromes c' are typically dimeric with each c-type haem-containing monomer folding as a four-α-helix bundle. Their hydrophobic and crowded distal sites impose severe restrictions on the binding of distal ligands, including diatomic gases. By contrast, NO binds to the proximal haem face in a similar manner to that of the eukaryotic NO sensor, soluble guanylate cyclase and bacterial analogues. In this review, we focus on how structural features of cytochromes c' influence haem spectroscopy and reactivity with NO, CO and O2. We also discuss the relevance of cytochrome c' to understanding the mechanisms of gas binding to haem-based sensor proteins.

  11. Remote Sensing-Based Exploration of Structurally-Related Mineralizations around Mount Isa, Queensland, Australia

    Directory of Open Access Journals (Sweden)

    Sandra Jakob

    2016-04-01

    Full Text Available Hyperspectral imaging is a powerful tool for mineral mapping and increasingly used in poorly-accessible areas. It only requires a limited amount of validation sample points, but can fail to discriminate spectrally-similar features. In this manuscript, we show that we improve the identification of interesting targets by including geomorphological data in the spectral mapping scheme. We jointly use geomorphic and spectral features to locate gossanous ironstone ridges as an indicator for possible Pb-Zn-Ag-mineralization and provide an application around Mount Isa and George Fisher/Hilton mine, Queensland, Australia. We combine hyperspectral HyMap data using mixture tuned matched filtering with topographical indices, such as maximum curvature and the topographical position index. As it is often the case with structurally-controlled mineralization, the amount of training sites is limited, and supervised classification methods cannot be implemented. Therefore, we implement expert knowledge in a decision tree to take advantage of the relationship between mineralization, alteration and structure. Optimized rock sampling and spectral measurements provided data for validation. We are able to map sets of gossanous ridges with a minimum of validation points, not only within the Mount Isa mining area itself, but also outside the commonly-accepted host rocks. The ridges are parallel to north-south trending geomorphological features and probably associated with the Paroo fault zone. Similarities between the ridges were confirmed by field observations, spectral measurements and a qualitative rock sample analysis. We identified new mineralized ridges that we could subsequently attribute to a poorly-known and sub-economic deposit known as the Mount Novit Pb-Zn-deposit.

  12. A missense mutation in CHS1, a TIR-NB protein, induces chilling sensitivity in Arabidopsis.

    Science.gov (United States)

    Wang, Yuancong; Zhang, Yao; Wang, Zheng; Zhang, Xiaoyan; Yang, Shuhua

    2013-08-01

    Low temperature is an environmental factor that affects plant growth and development and plant-pathogen interactions. How temperature regulates plant defense responses is not well understood. In this study, we characterized chilling-sensitive mutant 1 (chs1), and functionally analyzed the role of the CHS1 gene in plant responses to chilling stress. The chs1 mutant displayed a chilling-sensitive phenotype, and also displayed defense-associated phenotypes, including extensive cell death, the accumulation of hydrogen peroxide and salicylic acid, and an increased expression of PR genes: these phenotypes indicated that the mutation in chs1 activates the defense responses under chilling stress. A map-based cloning analysis revealed that CHS1 encodes a TIR-NB-type protein. The chilling sensitivity of chs1 was fully rescued by pad4 and eds1, but not by ndr1. The overexpression of the TIR and NB domains can suppress the chs1-conferred phenotypes. Interestingly, the stability of the CHS1 protein was positively regulated by low temperatures independently of the 26S proteasome pathway. This study revealed the role of a TIR-NB-type gene in plant growth and cell death under chilling stress, and suggests that temperature modulates the stability of the TIR-NB protein in Arabidopsis.

  13. Influence of CVD process duration on morphology, structure and sensing properties of carbonaceous-palladium films

    International Nuclear Information System (INIS)

    We present the nanocomposite carbonaceous-palladium (C-Pd) thin films prepared by physical vapor deposition (PVD) and chemical vapor deposition (CVD) methods. Scanning electron microscope (SEM) and transmission electron microscope (TEM) methods were used to study the topography, morphology and structure of carbon and palladium nanograins contained in these films. The quantitative analysis of the elemental composition of C-Pd films was determined by energy-dispersive spectroscopy (EDS). The initial PVD films were modified in a CVD quartz reactor using xylene (the mixture of isomers) as a modifying factor at different times (5, 10 and 30 minutes) at a constant temperature of 650°C in atmospheric pressure. It was observed that the average size of palladium nanograins increased with an increasing duration of modification process. The differences in microstructures observed in the CVD films modified at different times, affect their response in measurements of resistance changes in the gas containing H2 in various concentrations. All samples were measured by cathodoluminescence (CL) method. In CL studies a large amount of objects with high intensity of CL was found. Some of them show the emission bands both at 450 nm and 750 nm. Other reveals emission band only at 450 nm. CL observations show that Pd nanograins coated by graphite shells exhibit optical activity

  14. Remote sensing of size structure of phytoplankton communities using optical properties of the Chukchi and Bering Sea shelf region

    Science.gov (United States)

    Fujiwara, A.; Hirawake, T.; Suzuki, K.; Saitoh, S.-I.

    2011-12-01

    Recent ocean warming and subsequent sea ice decline resulting from climate change could affect the northward shift of the ecosystem structure in the Chukchi Sea and Bering Sea shelf region (Grebmeier et al., 2006b). The size structure of phytoplankton communities provides an index of trophic levels that is crucial to understanding the mechanisms underlying such ecosystem changes and their implications for the future. This study proposes a new ocean color algorithm for deriving this characteristic by using the region's optical properties. The size derivation model (SDM) estimates the phytoplankton size index FL on the basis of size-fractionated chlorophyll-a (chl-a) using the light absorption coefficient of phytoplankton, aph(λ), and the backscattering coefficient of suspended particles including algae, bbp(λ). FL was defined as the ratio of algal biomass attributed to cells larger than 5 μm to the total. It was expressed by a multiple regression model using the aph(λ) ratio, aph(488)/aph(555), which varies with phytoplankton pigment composition, and the spectral slope of bbp(λ), γ, which is an index of the mean suspended particle size. A validation study demonstrated that 69% of unknown data are correctly derived within FL range of ±20%. The spatial distributions of FL for the cold August of 2006 and the warm August of 2007 were compared to examine application of the SDM to satellite remote sensing. The results suggested that phytoplankton size was responsive to changes in sea surface temperature. Further analysis of satellite-derived FL values and other environmental factors can advance our understanding of ecosystem structure changes in the shelf region of the Chukchi and Bering Seas.

  15. Structural Analysis for Gold Mineralization Using Remote Sensing and Geochemical Techniques in a GIS Environment: Island of Lesvos, Hellas

    International Nuclear Information System (INIS)

    Exploration for epithermal Au has been active lately in the Aegean Sea of the eastern Mediterranean Basin, both in the islands of the Quaternary arc and in those of the back-arc region. The purpose of this study was the structural mapping and analysis for a preliminary investigation of possible epithermal gold mineralization, using remotely sensed data and techniques, structural and field data, and geochemical information, for a specific area on the Island of Lesvos. Therefore, Landsat-TM and SPOT-Pan satellite images and the Digital Elevation Model (DEM) of the study area were processed digitally using spatial filtering techniques for the enhancement and recognition of the geologically significant lineaments, as well as algebraic operations with band ratios and Principal Component Analysis (PCA), for the identification of alteration zones. Statistical rose diagrams and a SCHMIDT projection Stereo Net were generated from the lineament maps and the collected field data (dip and strike measurements of faults, joints, and veins), respectively. The derived lineament map and the band ratio images were manipulated in a GIS environment, in order to study the relation of the tectonic pattern to both the alteration zoning and the geomorphology of the volcanic field of the study area. Target areas of high interest for possible mineralization also were specified using geochemical techniques, such as X-Ray Diffraction (XRD) analysis, trace-element, and fluid-inclusion analysis. Finally, preliminary conclusions were derived about possible mineralization, the type (high or low sulfidation), and the extent of mineralization, by combining the structural information with geochemical information

  16. Linking Remotely Sensed Functional Diversity of Structural Traits to the Radiative Regime of a Temperate Mixed Forest

    Science.gov (United States)

    Schneider, F. D.; Morsdorf, F.; Furrer, R.; Schmid, B.; Schaepman, M. E.

    2015-12-01

    Patterns of functional diversity reflect the inter- and intraspecific variability of plant traits and are linked to other aspects of biodiversity, environmental factors and ecosystem function. To study the patterns at plot and stand level, spatially continuous trait measurements are required. Remote sensing methods based on airborne observations can offer such continuous high-resolution measurements, resolving individual trees of a forest at a regional extent. The study was performed at the Laegern forest, a temperate mixed forest dominated by deciduous and coniferous trees (Fagus sylvatica, Picea abies; 47°28'42.0" N, 8°21'51.8" E, 682 m asl; Switzerland). Canopy height, plant area index and foliage height diversity were derived from full-waveform airborne laser scanning data. These structural traits were used to calculate functional richness, functional evenness and functional divergence at a range of scales. A Bayesian multiresolution scale analysis was used to infer the scales at which functional diversity patterns occur. The radiative regime of the forest was simulated using the 3D radiative transfer model DART. Using a voxel-based forest reconstruction allowed us to derive top of canopy, bottom of canopy and absorbed photosynthetically active radiation. The results of this study will provide new insights on linking forest canopy structure to the radiative regime of the forest. Light availability is a critical factor determining plant growth and competition. Within canopy light scattering is mainly driven by the arrangement of leaves and their leaf optical properties. Therefore, we expect a link between the structural complexity of the forest as encompassed by functional diversity and the light availability within and below the canopy. Ultimately, this information can be used in dynamic ecosystem models such as ED2, allowing us to predict the influence of functional diversity and radiative properties on ecosystem functioning under current conditions and

  17. Application of PALSAR-2 remote sensing data for structural geology and topographic mapping in Kelantan river basin, Malaysia

    Science.gov (United States)

    Beiranvand Pour, Amin; Hashim, Mazlan

    2016-06-01

    Natural hazards of geological origin are one of major problem during heavy monsoons rainfall in Kelantan state, peninsular Malaysia. Several landslides occur in this region are obviously connected to geological and topographical features, every year. Satellite synthetic aperture radar (SAR) data are particularly applicable for detection of geological structural and topographical features in tropical conditions. In this study, Phased Array type L-band Synthetic Aperture Radar (PALSAR-2), remote sensing data were used to identify high potential risk and susceptible zones for landslide in the Kelantan river basin. Adaptive Local Sigma filter was selected and applied to accomplish speckle reduction and preserving both edges and features in PALSAR-2 fine mode observation images. Different polarization images were integrated to enhance geological structures. Additionally, directional filters were applied to the PALSAR-2 Local Sigma resultant image for edge enhancement and detailed identification of linear features. Several faults, drainage patterns and lithological contact layers were identified at regional scale. In order to assess the results, fieldwork and GPS survey were conducted in the landslide affected zones in the Kelantan river basin. Results demonstrate the most of the landslides were associated with N-S, NNW-SSE and NE-SW trending faults, angulate drainage pattern and metamorphic and Quaternary units. Consequently, geologic structural map were produced for Kelantan river basin using recent PALSAR-2 data, which could be broadly applicable for landslide hazard assessment and delineation of high potential risk and susceptible areas. Landslide mitigation programmes could be conducted in the landslide recurrence regions for reducing catastrophes leading to economic losses and death.

  18. Mediterranean desert dust outbreaks and their vertical structure based on remote sensing data

    Science.gov (United States)

    Gkikas, A.; Basart, S.; Hatzianastassiou, N.; Marinou, E.; Amiridis, V.; Kazadzis, S.; Pey, J.; Querol, X.; Jorba, O.; Gassó, S.; Baldasano, J. M.

    2015-10-01

    The main aim of the present study is to describe the vertical structure of the intense Mediterranean dust outbreaks, based on the use of satellite and surface-based retrievals/measurements. Strong and extreme desert dust (DD) episodes are identified at 1° × 1° spatial resolution, over the period March 2000-February 2013, through the implementation of an updated objective and dynamic algorithm. According to the algorithm, strong DD episodes occurring at a specific place correspond to cases in which the daily aerosol optical depth at 550 nm (AOD550 nm) exceeds or equals the long-term mean AOD550 nm (Mean) plus two standard deviations (SD) value being smaller than Mean + 4 · SD. Extreme DD episodes correspond to cases in which the daily AOD550 nm value equals or exceeds Mean + 4 · SD. For the identification of DD episodes additional optical properties (Ångström exponent, fine fraction, effective radius and Aerosol Index) derived by the MODIS-Terra & Aqua (also AOD retrievals), OMI-Aura and EP-TOMS databases are used as inputs. According to the algorithm using MODIS-Terra data, over the period March 2000-February 2013, strong DD episodes occur more frequently (up to 9.9 episodes yr-1) over the western Mediterranean while the corresponding frequencies for the extreme ones are smaller (up to 3.3 episodes yr-1, central Mediterranean Sea). In contrast to their frequency, dust episodes are more intense (AODs up to 4.1), over the central and eastern Mediterranean Sea, off the northern African coasts. Slightly lower frequencies and higher intensities are found when the satellite algorithm operates based on MODIS-Aqua retrievals, for the period 2003-2012. The performance of the satellite algorithm is assessed against surface-based daily data from 109 sun-photometric (AERONET) and 22 PM10 stations. The agreement between AERONET and MODIS AOD is satisfactory (R = 0.505 - 0.75) improving considerably when MODIS level 3 retrievals with higher sub-grid spatial

  19. Acoustic remote sensing of the ABL wind structure in Moscow city

    Science.gov (United States)

    Akhiyarova, Ksenia; Lokoshchenko, Mikhail

    2014-05-01

    The dynamics of wind velocity V in the atmospheric boundary layer (ABL) above Moscow city have been analyzed by long-term data of sodar measurements. The Doppler 'MODOS' sodar of METEK firm (Germany) production operates at Moscow University since 2004. Besides, data of two cup anemometers on 7 and 15 m heights inside 'dead zone' of the sodar have been added to analysis. The methodical questions of comparison between in situ and sodar data about V are discussed in details. The profile of wind velocity V in the air layer from 7 to 500 m has been received and analyzed in average of eight last years from 2004 to 2012. In average it is close to logarithmical law up to 60 m so that this value seems to be equal to the surface air layer height. It should be noted that sodar due to its high spatial resolution (20 m) allows studying the ABL fine-structure. Among others, the daily course of V has been investigated in details at different heights. It demonstrates clear daily maximum and nocturnal minimum at any height below 80 m and, vice versa, nocturnal maximum and daily minimum above 140 m everywhere. The air layer from 80 to 140 m represents intermediate zone of smoothed daily course of V. In general this zone corresponds to cross-over height (ideal level where the daily course of wind velocity is absent) but it is noted by important additional feature - minimum in the morning which is statistically significant. Besides, with using of the sodar data it's possible to study mostly interesting weather phenomena such as thunderstorm. Total sampling of this weather event was equal to 137 cases in Moscow from 2004 to 2012. Averaged values both of V, and of its vertical component W have been analyzed during these thunderstorms. As it was shown both V, and W values are increased at the moment of this phenomenon starting. The wind velocity at this moment is in average nearly on 1 m/s higher than three hours before thunderstorm and this increase is statistically significant with 0

  20. Mediterranean intense desert dust outbreaks and their vertical structure based on remote sensing data

    Science.gov (United States)

    Gkikas, Antonis; Basart, Sara; Hatzianastassiou, Nikos; Marinou, Eleni; Amiridis, Vassilis; Kazadzis, Stelios; Pey, Jorge; Querol, Xavier; Jorba, Oriol; Gassó, Santiago; Baldasano, José Maria

    2016-07-01

    The main aim of the present study is to describe the vertical structure of the intense Mediterranean dust outbreaks, based on the use of satellite and surface-based retrievals/measurements. Strong and extreme desert dust (DD) episodes are identified at 1° × 1° spatial resolution, over the period March 2000-February 2013, through the implementation of an updated objective and dynamic algorithm. According to the algorithm, strong DD episodes occurring at a specific place correspond to cases in which the daily aerosol optical depth at 550 nm (AOD550 nm) exceeds or equals the long-term mean AOD550 nm (Mean) plus two standard deviations (SD), which is also smaller than Mean+4 × SD. Extreme DD episodes correspond to cases in which the daily AOD550 nm value equals or exceeds Mean+4 × SD. For the identification of DD episodes, additional optical properties (Ångström exponent, fine fraction, effective radius and aerosol index) derived by the MODIS-Terra & Aqua (also AOD retrievals), OMI-Aura and EP-TOMS databases are used as inputs. According to the algorithm using MODIS-Terra data, over the period March 2000-February 2013, strong DD episodes occur more frequently (up to 9.9 episodes year-1) over the western Mediterranean, while the corresponding frequencies for the extreme ones are smaller (up to 3.3 episodes year-1, central Mediterranean Sea). In contrast to their frequency, dust episodes are more intense (AODs up to 4.1), over the central and eastern Mediterranean Sea, off the northern African coasts. Slightly lower frequencies and higher intensities are found when the satellite algorithm operates based on MODIS-Aqua retrievals, for the period 2003-2012. The consistency of the algorithm is successfully tested through the application of an alternative methodology for the determination of DD episodes, which produced similar features of the episodes' frequency and intensity, with just slightly higher frequencies and lower intensities. The performance of the satellite

  1. Molecular structure, optical, electrical and sensing properties of PANI-based coatings with silver nanoparticles deposited from the active gas phase

    Energy Technology Data Exchange (ETDEWEB)

    Ragachev, A.A., E-mail: rogachev78@mail.ru [International Chinese-Belorussian Scientific Laboratory on Vacuum-Plasma Technology, College of Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094 (China); National Research Tomsk Polytechnic University, 30, Lenin Avenue, Tomsk 634050 (Russian Federation); Yarmolenko, M.A. [International Chinese-Belorussian Scientific Laboratory on Vacuum-Plasma Technology, College of Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094 (China); National Research Tomsk Polytechnic University, 30, Lenin Avenue, Tomsk 634050 (Russian Federation); Xiaohong, Jiang [International Chinese-Belorussian Scientific Laboratory on Vacuum-Plasma Technology, College of Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094 (China); Shen, Ruiqi [Key Lab of Soft Chemistry and Functional Materials of Ministry of Education, Nanjing University of Science and Technology, Nanjing 210094 (China); Luchnikov, P.A. [National Research Tomsk Polytechnic University, 30, Lenin Avenue, Tomsk 634050 (Russian Federation); Rogachev, A.V. [Francisk Skorina Gomel State University, 104, Sovetskaya Street, Gomel 246019 (Belarus)

    2015-10-01

    Highlights: • PANI-based coatings were deposited by plasma chemical solvent-free method. • PANI + AgCl coating has a partially doped structure with low variation in size of oxidized and reduced PANI units. • The increasing of the sensing performance of this coating was established at the low frequency region of impedance spectra. - Abstract: The plasma chemical solvent-free method of doped and nanocomposite polyaniline-based (PANI-based) conductive coatings deposition was elaborated. Molecular structure, morphology, optical, electrical and sensing properties of PANI-based coating were investigated by Fourier transform infrared, UV–vis, impedance spectroscopy methods and transmittance electron microscopy. The synthesized PANI-based coatings containing silver nanoparticles have a partially doped structure with low variation in size of oxidized and reduced PANI units. The nanocomposite PANI-based coatings were deposited onto interdigital capacitor for ammonia gas sensing applications. The increasing of the sensing performance of the PANI-based coatings with silver nanoparticles was established in particular at the low frequency region of impedance spectra. The high sensitivity and linearity of this sensor response were examined at a direct and alternating voltage with ammonia concentrations up to 10 ppm.

  2. Molecular structure, optical, electrical and sensing properties of PANI-based coatings with silver nanoparticles deposited from the active gas phase

    International Nuclear Information System (INIS)

    Highlights: • PANI-based coatings were deposited by plasma chemical solvent-free method. • PANI + AgCl coating has a partially doped structure with low variation in size of oxidized and reduced PANI units. • The increasing of the sensing performance of this coating was established at the low frequency region of impedance spectra. - Abstract: The plasma chemical solvent-free method of doped and nanocomposite polyaniline-based (PANI-based) conductive coatings deposition was elaborated. Molecular structure, morphology, optical, electrical and sensing properties of PANI-based coating were investigated by Fourier transform infrared, UV–vis, impedance spectroscopy methods and transmittance electron microscopy. The synthesized PANI-based coatings containing silver nanoparticles have a partially doped structure with low variation in size of oxidized and reduced PANI units. The nanocomposite PANI-based coatings were deposited onto interdigital capacitor for ammonia gas sensing applications. The increasing of the sensing performance of the PANI-based coatings with silver nanoparticles was established in particular at the low frequency region of impedance spectra. The high sensitivity and linearity of this sensor response were examined at a direct and alternating voltage with ammonia concentrations up to 10 ppm

  3. The crystal structure of the tandem-PAS sensing domain of Campylobacter jejuni chemoreceptor Tlp1 suggests indirect mechanism of ligand recognition.

    Science.gov (United States)

    Machuca, Mayra A; Liu, Yu C; Beckham, Simone A; Gunzburg, Menachem J; Roujeinikova, Anna

    2016-05-01

    Chemotaxis and motility play an important role in the colonisation of avian and human hosts by Campylobacter jejuni. Chemotactic recognition of extracellular signals is mediated by the periplasmic sensing domain of methyl-accepting chemotactic proteins (membrane-embedded receptors). In this work, we report a high-resolution structure of the periplasmic sensing domain of transducer-like protein 1 (Tlp1), an aspartate receptor of C. jejuni. Crystallographic analysis revealed that it contains two Per-Arnt-Sim (PAS) subdomains. An acetate and chloride ions (both from the crystallisation buffer) were observed bound to the membrane-proximal and membrane-distal PAS subdomains, respectively. Surprisingly, despite being crystallised in the presence of aspartate, the structure did not show any electron density corresponding to this amino acid. Furthermore, no binding between the sensing domain of Tlp1 and aspartate was detected by microcalorimetric experiments. These structural and biophysical data suggest that Tlp1 does not sense aspartate directly; instead, ligand recognition is likely to occur indirectly via an as yet unidentified periplasmic binding protein. PMID:26923153

  4. Comparing the Cloud Vertical Structure Derived from Several Methods Based on Radiosonde Profiles and Ground-based Remote Sensing Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Costa-Suros, M.; Calbo, J.; Gonzalez, J. A.; Long, Charles N.

    2014-08-27

    The cloud vertical distribution and especially the cloud base height, which is linked to cloud type, is an important characteristic in order to describe the impact of clouds in a changing climate. In this work several methods to estimate the cloud vertical structure (CVS) based on atmospheric sounding profiles are compared, considering number and position of cloud layers, with a ground based system which is taken as a reference: the Active Remote Sensing of Clouds (ARSCL). All methods establish some conditions on the relative humidity, and differ on the use of other variables, the thresholds applied, or the vertical resolution of the profile. In this study these methods are applied to 125 radiosonde profiles acquired at the ARM Southern Great Plains site during all seasons of year 2009 and endorsed by GOES images, to confirm that the cloudiness conditions are homogeneous enough across their trajectory. The overall agreement for the methods ranges between 44-88%; four methods produce total agreements around 85%. Further tests and improvements are applied on one of these methods. In addition, we attempt to make this method suitable for low resolution vertical profiles, which could be useful in atmospheric modeling. The total agreement, even when using low resolution profiles, can be improved up to 91% if the thresholds for a moist layer to become a cloud layer are modified to minimize false negatives with the current data set, thus improving overall agreement.

  5. Grain refinement and macrosegregation behavior of direct chill cast Al-Zn-Mg-Cu alloy under combined electromagnetic fields

    Directory of Open Access Journals (Sweden)

    Yu-bo Zuo

    2015-09-01

    Full Text Available The combined electromagnetic fields were achieved by the application of an alternating magnetic field and a stationary magnetic field and were used during direct chill (DC casting process to control the microstructure and macrosegregation of an Al-Zn-Mg-Cu alloy. Ingot microstructures were analyzed under an optical microscope (Leica DMR. The composition at different locations in the ingots was measured with inductively coupled plasma mass spectrometry (ICP method. The results showed that the grain structure is transformed from dendrite to equiaxed structure and significantly refined with the application of combined electromagnetic fields. The uniformity of microstructure is also greatly improved. The combined electromagnetic fields show a significant effect on the distribution of elements. The negative macrosegregation in the centre area of the ingot is obviously reduced.

  6. Fine-scale, multidimensional spatial patterns of forest canopy structure derived from remotely sensed and simulated datasets

    Science.gov (United States)

    Frazer, Gordon Wilson

    Forests are not simply storehouses of timber or wood fibre for human consumption and economic development. They represent structurally and ecologically rich habitat for an estimated 40 percent of the earth's extant species, and form the functional interface between the biosphere and atmosphere for some 27 percent of the earth's terrestrial surface. Forests, therefore, play a vital role in the maintenance of biodiversity and the regulation of local to global scale ecosystem processes and functions. Present strategies for conserving biodiversity in managed forests are based on the notion that maintaining the full range of structural conditions historically present in natural forests is the best approach for assuring the long-term persistence of a broad range of native species. The overarching goal of this dissertation is to contribute to the development of novel forest measurements that are relevant to organisms and ecosystems, and much needed by forest scientists and managers to recognize and retain the key elements and patterns of forest structure that are crucial for the conservation of forest biodiversity. This study focuses explicitly on fine-spatial-scale, multidimensional patterns of forest canopy structure based on the assumption that the 'canopy' is the primary focal site of complex interactions between vegetation and the physical environment. Two disparate remote sensing technologies---ground-based hemispherical (fisheye) canopy photography and airborne discrete-return LiDAR---are employed to characterize angular, vertical, and horizontal patterns of forest canopy structure. A quantitative technique is developed for precise measurements of gap fraction (P), element clumping (O), mean projection coefficient (G), and leaf area index (L) from sequences (sets) of black and white pixels extracted at specific view angles in digital fisheye photos. Results are compared with three other leading techniques and validated using well-documented simulated and real

  7. Film with anthocyanins as an indicator of chilled pork deterioration

    Directory of Open Access Journals (Sweden)

    Luana Baptista Golasz

    2013-02-01

    Full Text Available An indicator can be defined as a substance which indicates the presence or absence of another substance or the degree of a certain reaction through characteristic changes, especially color. Therefore, the aim of this work is to evaluate the performance of a bio-based film with anthocyanin as an indicator of chilled pork deterioration. A film made of cassava starch, glycerol, and grape anthocyanins was prepared using the casting technique. Pork loin samples were put in Petri dishes containing an anthocyanin film on the bottom and stored at 4 ºC. Psychrotrophic microorganism count and the pH of the pork loin samples were analyzed for a 14 day- period. At the same time, the films were subjected to colorimetric analysis using D65 illuminant and the CIELAB system. Chroma and hue angle data for these films were evaluated by Anova and Dunnett's test. An increase in the microbial population and in the pH was observed over the storage period as result of pork deterioration. Color changes were also identified in the film. However, only at the beginning of the storage period was it possible to establish a correlation between film color and pork deterioration. The shelf life end-point could not be clearly detected by the film.

  8. Running Club Warm Up Staves Off Winter's Chill

    CERN Multimedia

    2001-01-01

    Not deterred by winter's chill, over 900 runners met at the CERN Prévesin site for Escalade training. Think the sudden cold snap is a reason to stay indoors? Think again! The CERN running club has just recently had the honour of holding the November 11th Escalade training session, and with over 900 runners present at the Prévessin site it was clear that the chilly temperatures were no barrier whatsoever. The story behind Escalade training starts back in 1977 when a group of running enthusiasts from the Stade Genève club decided to organize a running race in the Old Town in conjunction with the Escalade festivities. They were told that no normal people would think of organizing a running race in the month of December, but fortunately they ignored the advice! From the initial 50 or so runners, these Escalade races have grown into an institution and now attract upwards of 15,000 people of all ages from 5 to over 80 each year. And with over 30% of each year's runners participat...

  9. Start of the big chill for the LHC

    CERN Multimedia

    2007-01-01

    The cooling of Sector 7-8 of the LHC, the first to undergo the process, is under way to the 1.9 K necessary for superconductivity. During the night of 14 to 15 March, an important milestone was reached when the entire sector was cooled to 4.5 K, the temperature of liquid helium. The two graphs above show the progression of cooling in Sector 7-8. The first gives the status of the sector on Tuesday 6 March at 4:00 pm, the second on Wednesday 7 March at 10:00 am. Each square represents a magnet.It's the start of the big chill for the LHC. Since the middle of January, the teams from the Accelerator Cryogenics group have been working to cool down the first sector of the machine. Three kilometres of magnets between Point 7 (Ferney-Voltaire) and Point 8 (Prévessin) are to be cooled to 1.9 Kelvin (-271°C), colder than outer space. The first step in the process was to cool the sector to 80 K. Following mechanical and electrical integrity tests at this temperature, it was then further cooled to 20 K for additional e...

  10. Scaling Analysis of Ocean Surface Turbulent Heterogeneities from Satellite Remote Sensing: Use of 2D Structure Functions, methodology and applications

    Science.gov (United States)

    Schmitt, F. G.; Pannimpullath Remanan, R.; Loisel, H.

    2015-12-01

    Satellite remote sensing observations allow the ocean surface to be sampled over large spatio-temporal scales. The images provided from visible and thermal infrared satellite observations are widely used in physical, biological, and ecological oceanography. The present work proposes a method to understand the multi-scaling properties of satellite products such as the Chlorophyll-a (Chl-a), and the Sea Surface Temperature (SST). The specific objectives of this study are to show how the small scale heterogeneities of satellite images can be characterised using tools borrowed from the fields of turbulence. We show how the structure function, which is classically used in the frame of scaling time series analysis, can be used also in 2D. The main advantage of this method is that it can be applied to process images which have missing data. Based on both simulated and real images, we demonstrate that coarse-graining (CG) of a gradient modulus transform of the original image does not provide correct scaling exponents. We show, using a fractional Brownian simulation in 2D, that the structure function (SF) can be used with randomly sampled couple of points, and verify that 1 million of couple of points provides enough statistics. After this methodological study, some applications are presented: the nonlinear moment function ζ(q) is fitted using the lognormal model with 2 parameters, the Hurst index H and the intermittency μ. The values of H and μ are discussed for 4 different parameters (Chl-a, SST, Rrs-443 and Rrs-555) and for different locations, chosen among different contrasted regions of the ocean, characterized by high spatial heterogeneity in Chl-a and SST.

  11. Deterministic sensing matrices in compressive sensing: a survey.

    Science.gov (United States)

    Nguyen, Thu L N; Shin, Yoan

    2013-01-01

    Compressive sensing is a sampling method which provides a new approach to efficient signal compression and recovery by exploiting the fact that a sparse signal can be suitably reconstructed from very few measurements. One of the most concerns in compressive sensing is the construction of the sensing matrices. While random sensing matrices have been widely studied, only a few deterministic sensing matrices have been considered. These matrices are highly desirable on structure which allows fast implementation with reduced storage requirements. In this paper, a survey of deterministic sensing matrices for compressive sensing is presented. We introduce a basic problem in compressive sensing and some disadvantage of the random sensing matrices. Some recent results on construction of the deterministic sensing matrices are discussed.

  12. Structural modeling of the Zagros fold-and-thrust belt (Iraq) combining field work and remote sensing techniques

    Science.gov (United States)

    Reif, D.; Grasemann, B.; Faber, R.; Lockhart, D.

    2009-04-01

    The Zagros fold-and-thrust belt is known for its spectacular fold trains, which have formed in detached Phanerozoic sedimentary cover rocks above a shortened crystalline Precambrian basement. Orogeny evolved through the Late Cretaceous to Miocene collision between the Arabian and Eurasian plate, during which the Neotethys oceanic basin was closed. Still active deformation shortening in the order of 2-2.5 cm/yr is partitioned in S-SW directed folding and thrusting of the Zagros fold-and-thrust belt and NW-SE to N-S trending dextral strike slip faults. The sub-cylindrical doubly-plunging fold trains with wavelengths of 5 - 10 km host more than half of the world's hydrocarbon reserves in mostly anticlinal traps. In this work we investigate the three dimensional structure of the Zagros fold-and-thrust belt in the Kurdistan region of Iraq. The mapped region is situated NE from the city of Erbil and comprises mainly Cretaceous to Cenozoic folded sediments consisting of mainly limestones, dolomites, sandstones, siltstones, claystones and conglomerates. Although the overall security situation in Kurdistan is much better than in the rest of Iraq, structural field mapping was restricted to sections along the main roads perpendicular to the strike of the fold trains, mainly because of the contamination of the area with landmines and unexploded ordnance, a problem that dates back to the end of World War Two. Landmines were also used by the central government in the 1960s and 1970s in order to subdue Kurdish groups. During the 1980-1988 Iran-Iraq War, the north was mined again. In order to extend the structural measurements statistically over the investigated area resulting in a three-dimensional model of the fold trains, we used the Fault Trace module of the WinGeol software (www.terramath.com). This package allows the interactive mapping and visualization of the spatial orientations (i.e. dip and strike) of geological finite planar structures (e.g. faults, lithological

  13. Deleuze e A lógica do sentido: o problema da estrutura Deleuze and The logic of sense: structure as a problem

    Directory of Open Access Journals (Sweden)

    Alessandro Carvalho Sales

    2006-01-01

    Full Text Available Este texto pretende acompanhar os principais movimentos apresentados pelo filósofo Gilles Deleuze para propor uma estrutura do sentido, de acordo com a Lógica do sentido (1969. Para tanto, tentando nos alçar ao estruturalismo muito particular de Deleuze, seguiremos especialmente alguns argumentos estabelecidos entre a quarta (Das dualidades e a oitava (Da estrutura séries desse livro, bem como pontos do artigo Em que se pode reconhecer o estruturalismo? (1972.This article intends to follow the main movements presented by the philosopher Gilles Deleuze (1925-1995. to propose a strucuture of the sense according to The logic of sense (1969. In order to do this, trying to achieve the very particular Deleuzian structuralism, we will follow especially some arguments established between the fourth (Of dualities. and the eighth (Of structure. series of this book, as well as points of the text How do we recognize structuralism? (1974.

  14. Analysis of Sense of Language Based on Psychological Structure Theory%基于心理结构理论的语感培养分析

    Institute of Scientific and Technical Information of China (English)

    曲伟红

    2015-01-01

    语感培养是语文教学的重要内容。本文依据心理结构理论分析了语感以及语感形成的心理机制。即语感是大脑非自遣意识的心理活动,其形成方法可以通过自潜意识的压入和非自遣意识的直接感受两种方法进行培养。最后,本文指出了语感培养最核心的方法是热爱并体验生活,在此基础上对生活进行记录和反思,并通过读书进行对比与提升。%The cultivation of sense of language is the important content of Chinese teaching. Analysis of the psychological mechanism of sense of language is discussed according to the theory of psychological structure. The sense of language is a kind of psychological activity in non self promoting consciousness of brain. The forming of sense of language can be built by two methods which are pressing of self promoting consciousness and feeling of non self promoting consciousness. Finally, this paper points out the core method to cultivate the sense of language is loving of life, doing the reflection of life and im-proving by reading.

  15. Genome-wide Association Analysis of Ten Chilling Tolerance Indices at the Germination and Seedling Stages in Maize

    Institute of Scientific and Technical Information of China (English)

    Juan Huang; Jianhua Zhang; Wenzhen Li; Wei Hu; Lichao Duan; Yang Feng; Fazhan Qiu

    2013-01-01

    Maize seedlings are very sensitive to chilling,especially during the transition phase from heterotrophic to autotrophic growth.Genetic dissection of the genetic basis of chilling tolerance would provide useful information for genetic improvement of maize inbreds.In this study,genome-wide association analysis was conducted to explore the genetic architecture of maize chilling tolerance at the seed germination and seedling stages with an association panel of 125 inbreds.Ten tolerance indices (ratios of the performance of 10 germination rates and seedling growth-related traits under chilling stress and control conditions)were investigated to assess the ability of chilling tolerance of the inbreds,and a total of 43 single nucleotide polymorphisms associated with chilling tolerance were detected,with none of them being related to chilling tolerance at both the germination and seedling stages simultaneously.Correlation analysis also revealed that the genetic basis of chilling tolerance at the seed germination stage is generally different from that at the seedling stage.In addition,a total of 40 candidate genes involving 31 of the 43 single nucleotide polymorphisms were predicted,and were grouped into five categories according to their functions.The possible roles of these candidate genes in chilling tolerance were also discussed.

  16. Chloroplast RNA-Binding Protein RBD1 Promotes Chilling Tolerance through 23S rRNA Processing in Arabidopsis

    Science.gov (United States)

    Yang, Leiyun; Yang, Fen; Wang, Yi; Zhu, Jian-Kang; Hua, Jian

    2016-01-01

    Plants have varying abilities to tolerate chilling (low but not freezing temperatures), and it is largely unknown how plants such as Arabidopsis thaliana achieve chilling tolerance. Here, we describe a genome-wide screen for genes important for chilling tolerance by their putative knockout mutants in Arabidopsis thaliana. Out of 11,000 T-DNA insertion mutant lines representing half of the genome, 54 lines associated with disruption of 49 genes had a drastic chilling sensitive phenotype. Sixteen of these genes encode proteins with chloroplast localization, suggesting a critical role of chloroplast function in chilling tolerance. Study of one of these proteins RBD1 with an RNA binding domain further reveals the importance of chloroplast translation in chilling tolerance. RBD1 is expressed in the green tissues and is localized in the chloroplast nucleoid. It binds directly to 23S rRNA and the binding is stronger under chilling than at normal growth temperatures. The rbd1 mutants are defective in generating mature 23S rRNAs and deficient in chloroplast protein synthesis especially under chilling conditions. Together, our study identifies RBD1 as a regulator of 23S rRNA processing and reveals the importance of chloroplast function especially protein translation in chilling tolerance. PMID:27138552

  17. Genome-wide association analysis of ten chilling tolerance indices at the germination and seedling stages in maize.

    Science.gov (United States)

    Huang, Juan; Zhang, Jianhua; Li, Wenzhen; Hu, Wei; Duan, Lichao; Feng, Yang; Qiu, Fazhan; Yue, Bing

    2013-08-01

    Maize seedlings are very sensitive to chilling, especially during the transition phase from heterotrophic to autotrophic growth. Genetic dissection of the genetic basis of chilling tolerance would provide useful information for genetic improvement of maize inbreds. In this study, genome-wide association analysis was conducted to explore the genetic architecture of maize chilling tolerance at the seed germination and seedling stages with an association panel of 125 inbreds. Ten tolerance indices (ratios of the performance of 10 germination rates and seedling growth-related traits under chilling stress and control conditions) were investigated to assess the ability of chilling tolerance of the inbreds, and a total of 43 single nucleotide polymorphisms associated with chilling tolerance were detected, with none of them being related to chilling tolerance at both the germination and seedling stages simultaneously. Correlation analysis also revealed that the genetic basis of chilling tolerance at the seed germination stage is generally different from that at the seedling stage. In addition, a total of 40 candidate genes involving 31 of the 43 single nucleotide polymorphisms were predicted, and were grouped into five categories according to their functions. The possible roles of these candidate genes in chilling tolerance were also discussed. PMID:23551400

  18. Influence of mist-chilling on post-harvest quality of fresh strawberries Cv. Mara des Bois and Gariguette

    Energy Technology Data Exchange (ETDEWEB)

    Allais, Irene [Cemagref, UMR Genial, 24, avenue des Landais B.P. 50085, 63172 Aubiere Cedex (France); Letang, Guy [Cemagref, UMR Genial, Parc de Tourvoie, B.P. 44, 92163 Antony Cedex (France)

    2009-09-15

    The aim of this study was to assess the impact of mist-chilling on high-grade strawberry post-harvest quality (Cultivars ''Gariguette'' and ''Mara des Bois''). Strawberries were chilled at 2 C using three processes: air blast chilling at 0.3 m s{sup -1} or 1 m s{sup -1} and mist-chilling at 1 m s{sup -1}. After chilling, fruits were submitted to different distribution chains characterised by different handling conditions and storage temperatures (2 C or 7 C) and by a 12 h retailing step at 20 C. Strawberry quality was assessed by measuring 7 parameters: weight loss, commercial loss, firmness, sugar content, acidity, colour and sensory quality. Compared to air-chilling, mist-chilling did not reduce chilling time but it reduced weight loss by 20-40%. Mist-chilling had no detrimental effect on commercial loss defined as the percentage of fruit more than 1/3 of surface affected. It did not induce any major changes on strawberry quality. Temperature fluctuations undergone during cold storage and retailing had a detrimental effect on weight loss. The beneficial effect of packaging on weight loss was confirmed. (author)

  19. Chilling requirements for hatching of a New Zealand isolate of Nematodirus filicollis.

    Science.gov (United States)

    Oliver, A-M B; Pomroy, W E; Ganesh, S; Leathwick, D M

    2016-08-15

    The eggs of some species of the parasitic nematode Nematodirus require a period of chilling before they can hatch; N. filicollis is one such species. This study investigated this requirement for chilling in a New Zealand strain of this species. Eggs of N. filicollis were extracted from lamb's faeces and incubated at 20°C to allow development to the third stage larvae within the egg. These eggs were then placed into tissue culture plates and incubated at: 2.7°C (±0.99), 3.6°C (±0.90), 4.7°C (±0.35), 6.4°C (±0.37), 8.0°C (±1.54) or 9.9°C (±0.14) for up to 224 days. At 14day intervals until day 84, then every 28 days, one plate was removed from each temperature and placed at 13.1°C (±0.44) for 14 days. Eggs were then assessed for hatching. From this data, chill units were calculated by subtracting the culture temperature from a constant threshold of 11°C and multiplying by the number of days for which the sample was cultured; then the Gompertz model fitted. Even though hatching overall was low, a greater proportion of eggs hatched with chill accumulation. Maximum hatching of eggs required 800-1000 chill units. Consequently in the field, more than one season of chilling would be required before hatching. As such a generation time could take more than one year to complete. This is different to the hatching dynamics of N. spathiger, the other main species found in New Zealand sheep, which does not display this requirement for chilling and hatches immediately once the third stage larvae are developed.

  20. Assessment of variations in taxonomic diversity, forest structure, and aboveground biomass using remote sensing along an altitudinal gradient in tropical montane forest of Costa Rica

    Science.gov (United States)

    Robinson, C. M.; Saatchi, S. S.; Clark, D.; Fricker, G. A.; Wolf, J.; Gillespie, T. W.; Rovzar, C. M.; Andelman, S.

    2012-12-01

    This research sought to understand how alpha and beta diversity of plants vary and relate to the three-dimensional vegetation structure and aboveground biomass along environmental gradients in the tropical montane forests of Braulio Carrillo National Park in Costa Rica. There is growing evidence that ecosystem structure plays an important role in defining patterns of species diversity and along with abiotic factors (climate and edaphic) control the phenotypic and functional variations across landscapes. It is well documented that strong subdivisions at local and regional scales are found mainly on geologic or climate gradients. These general determinants of biodiversity are best demonstrated in regions with natural gradients such as tropical montane forests. Altitudinal gradients provide a landscape scale changes through variations in topography, climate, and edaphic conditions on which we tested several theoretical and biological hypotheses regarding drivers of biodiversity. The study was performed by using forest inventory and botanical data from nine 1-ha plots ranging from 100 m to 2800 m above sea level and remote sensing data from airborne lidar and radar sensors to quantify variations in forest structure. In this study we report on the effectiveness of relating patterns of tree taxonomic alpha diversity to three-dimensional structure of a tropical montane forest using lidar and radar observations of forest structure and biomass. We assessed alpha and beta diversity at the species, genus, and family levels utilizing datasets provided by the Terrestrial Ecology Assessment and Monitoring (TEAM) Network. Through the comparison to active remote sensing imagery, our results show that there is a strong relationship between forest 3D-structure, and alpha and beta diversity controlled by variations in abiotic factors along the altitudinal gradient. Using spatial analysis with the aid of remote sensing data, we find distinct patterns along the environmental gradients

  1. Assessment of volatile profile as potential marker of chilling injury of basil leaves during postharvest storage.

    Science.gov (United States)

    Cozzolino, Rosaria; Pace, Bernardo; Cefola, Maria; Martignetti, Antonella; Stocchero, Matteo; Fratianni, Florinda; Nazzaro, Filomena; De Giulio, Beatrice

    2016-12-15

    The volatile profile of three sweet basil cultivars, "Italico a foglia larga", "Cammeo" and "Italiano classico", packaged in air at 4 or 12°C until 9days, was monitored by solid phase microextraction with GC-MS. Chilling injury (CI) score and electrolyte leakage were also assessed. In total, 71 volatile organic compounds (VOCs) were identified in the headspace of basil samples. A preliminary principal component analysis highlighted the dominant effect of the cultivar on VOCs profiles. Data analysis by post-transformation of projection to latent structures regression (ptPLS2) clarified the role played by time and temperature of storage. Temperature influenced the emission of volatiles during storage, with much lower total volatile emissions at 4°C compared to 12°C. Finally, a ptPLS2 regression model performed on VOCs and the two CI parameters allowed selection of 10 metabolites inversely correlated to both CI parameters, which can be considered potential markers of CI in basil leaves. PMID:27451192

  2. Sensing and Multiscale Structure

    CERN Document Server

    Fletcher, John F A

    2012-01-01

    We introduce a method of estimating parameters associated with a fractal random scattering medium, which utilizes the multiscale properties of the scattered field. The example of ray-density fluctuations beyond a phase screen with fractal slope is considered. An exact solution to the forward problem, in the case of the Brownian fractal, leads to an expression for the volatility of the slope. This expression is invariant under a change of probability measure, a fact which gives rise to the corresponding result for a (stationary) Ornstein-Uhlenbeck slope. We demonstrate that our analytical results are consistent with numerical simulations. Finally, an application to the determination of sea ice thickness via sonar is discussed.

  3. Structural and optical properties of ZnO nanostructures grown by aerosol spray pyrolysis: Candidates for room temperature methane and hydrogen gas sensing

    Energy Technology Data Exchange (ETDEWEB)

    Motaung, D.E., E-mail: dmotaung@csir.co.za [DST/CSIR Nanotechnology Innovation Centre, National Centre for Nano-Structured Materials, Council for Scientific and Industrial Research, P. O. Box 395, Pretoria 0001 (South Africa); Mhlongo, G.H., E-mail: gmhlongo@csir.co.za [DST/CSIR Nanotechnology Innovation Centre, National Centre for Nano-Structured Materials, Council for Scientific and Industrial Research, P. O. Box 395, Pretoria 0001 (South Africa); Kortidis, I. [Transparent Conductive Materials Lab, Institute of Electronic Structure and Laser, Foundation for Research and Technology Hellas, 100N. Plastira str., Vassilika Vouton, 70013 Heraklion, Crete (Greece); Nkosi, S.S., E-mail: skosi@csir.co.za [CSIR-National Laser Centre, 626 Meiring Naude Rd, Brummeria, Pretoria 0001 (South Africa); School of Physics, University of Witwatersrand, Private Bag X3, Johannesburg 2030 (South Africa); Malgas, G.F.; Mwakikunga, B.W.; Ray, S.Sinha [DST/CSIR Nanotechnology Innovation Centre, National Centre for Nano-Structured Materials, Council for Scientific and Industrial Research, P. O. Box 395, Pretoria 0001 (South Africa); Kiriakidis, G., E-mail: kiriakid@iesl.forth.gr [Transparent Conductive Materials Lab, Institute of Electronic Structure and Laser, Foundation for Research and Technology Hellas, 100N. Plastira str., Vassilika Vouton, 70013 Heraklion, Crete (Greece); University of Crete, Department of Physics, 710 03 Heraklion, Crete (Greece)

    2013-08-15

    We report on the synthesis of ZnO films by aerosol spray pyrolysis method at different deposition times. The surface morphology, crystal structure and the cross-sectional analysis of the prepared ZnO films were characterized by X-ray diffraction (XRD), focused ion beam scanning electron microscopy (FIB-SEM), atomic force microscopy (AFM) and high resolution transmission electron microscopy (HR-TEM). XRD analysis revealed that the ZnO films are polycrystalline in nature. Structural analysis exploiting cross-sectional TEM profile showed that the films composed of nano-particles and columnar structures growing perpendicular to the substrate. AFM revealed that the columnar structures have a higher surface roughness as compared to the nanoparticles. The effect of ZnO crystallite size and crystallinity on the gas sensing performance of hydrogen and methane gases was also evaluated. Sensing film based on ZnO nanoparticles has numerous advantages in terms of its reliability and high sensitivity. These sensing materials revealed an improved response to methane and hydrogen gases at room temperature due to their high surface area, indicating their possible application as a gas sensor.

  4. Structural and optical properties of ZnO nanostructures grown by aerosol spray pyrolysis: Candidates for room temperature methane and hydrogen gas sensing

    Science.gov (United States)

    Motaung, D. E.; Mhlongo, G. H.; Kortidis, I.; Nkosi, S. S.; Malgas, G. F.; Mwakikunga, B. W.; Ray, S. Sinha; Kiriakidis, G.

    2013-08-01

    We report on the synthesis of ZnO films by aerosol spray pyrolysis method at different deposition times. The surface morphology, crystal structure and the cross-sectional analysis of the prepared ZnO films were characterized by X-ray diffraction (XRD), focused ion beam scanning electron microscopy (FIB-SEM), atomic force microscopy (AFM) and high resolution transmission electron microscopy (HR-TEM). XRD analysis revealed that the ZnO films are polycrystalline in nature. Structural analysis exploiting cross-sectional TEM profile showed that the films composed of nano-particles and columnar structures growing perpendicular to the substrate. AFM revealed that the columnar structures have a higher surface roughness as compared to the nanoparticles. The effect of ZnO crystallite size and crystallinity on the gas sensing performance of hydrogen and methane gases was also evaluated. Sensing film based on ZnO nanoparticles has numerous advantages in terms of its reliability and high sensitivity. These sensing materials revealed an improved response to methane and hydrogen gases at room temperature due to their high surface area, indicating their possible application as a gas sensor.

  5. Structural and optical properties of ZnO nanostructures grown by aerosol spray pyrolysis: Candidates for room temperature methane and hydrogen gas sensing

    International Nuclear Information System (INIS)

    We report on the synthesis of ZnO films by aerosol spray pyrolysis method at different deposition times. The surface morphology, crystal structure and the cross-sectional analysis of the prepared ZnO films were characterized by X-ray diffraction (XRD), focused ion beam scanning electron microscopy (FIB-SEM), atomic force microscopy (AFM) and high resolution transmission electron microscopy (HR-TEM). XRD analysis revealed that the ZnO films are polycrystalline in nature. Structural analysis exploiting cross-sectional TEM profile showed that the films composed of nano-particles and columnar structures growing perpendicular to the substrate. AFM revealed that the columnar structures have a higher surface roughness as compared to the nanoparticles. The effect of ZnO crystallite size and crystallinity on the gas sensing performance of hydrogen and methane gases was also evaluated. Sensing film based on ZnO nanoparticles has numerous advantages in terms of its reliability and high sensitivity. These sensing materials revealed an improved response to methane and hydrogen gases at room temperature due to their high surface area, indicating their possible application as a gas sensor.

  6. Chill unit accumulation and necessity of rest breaking agents in South African table grape production regions

    Directory of Open Access Journals (Sweden)

    Avenant Eunice

    2014-01-01

    Full Text Available Cultivation of table grapes in warm regions of South Africa is complicated by problems associated with delayed and uneven bud break. Rest breaking agents, mainly hydrogen cyanamide, are applied to overcome these problems. The chill unit accumulation of the five major table grape production regions in South Africa was compared with the minimum chilling required to obtain a high bud break percentage (>80% and even bud break, defined as 200 hours between 0 and 10 ∘C, or 400 hours at 3 ∘C. The effect of chilling accumulation (0, 50, 100, 200, 400 and 800 hours at 3 ∘C on bud break of dormant cuttings of three table grape cultivars was investigated in controlled studies in a glass house over a three year period. Cuttings used in the study were collected from commercial vineyards in Saron in the Berg River Valley (representing a warm region and the Hex River Valley (representing a cool region. Sultanina and Sugraone cuttings from Saron required at least 200 hours at 3 ∘C to obtain a final bud break % of 80%+. A final bud break % of 80%+ was obtained with all Sultanina cuttings from Hex River Valley. Treatments receiving 400 and 800 hours at 3 ∘C, showed the most rapid rate of bud break. Prime cuttings collected from Saron, receiving 0, 50, 100 and 400 hours at 3 ∘C, showed a more rapid bud break process, as well as a higher final bud break % compared to Sugraone and Sultanina. It seems as if Prime has a lower chilling requirement than the other two cultivars. The model of Dokoozlian for quantifying chilling status is applicable to Saron and the Hex River Valley. The necessity of using rest breaking chemicals in the Saron area, for obtaining a high bud break % and even bud break, was confirmed. The Hex River Valley receives sufficient chilling temperatures to obtain a high bud break %, but rest breaking chemicals can be used to obtain more even bud break. The use of hydrogen cyanamide for improved and even bud break is a general

  7. Comparing the cloud vertical structure derived from several methods based on radiosonde profiles and ground-based remote sensing measurements

    Science.gov (United States)

    Costa-Surós, M.; Calbó, J.; González, J. A.; Long, C. N.

    2014-08-01

    The cloud vertical distribution and especially the cloud base height, which is linked to cloud type, are important characteristics in order to describe the impact of clouds on climate. In this work, several methods for estimating the cloud vertical structure (CVS) based on atmospheric sounding profiles are compared, considering the number and position of cloud layers, with a ground-based system that is taken as a reference: the Active Remote Sensing of Clouds (ARSCL). All methods establish some conditions on the relative humidity, and differ in the use of other variables, the thresholds applied, or the vertical resolution of the profile. In this study, these methods are applied to 193 radiosonde profiles acquired at the Atmospheric Radiation Measurement (ARM) Southern Great Plains site during all seasons of the year 2009 and endorsed by Geostationary Operational Environmental Satellite (GOES) images, to confirm that the cloudiness conditions are homogeneous enough across their trajectory. The perfect agreement (i.e., when the whole CVS is estimated correctly) for the methods ranges between 26 and 64%; the methods show additional approximate agreement (i.e., when at least one cloud layer is assessed correctly) from 15 to 41%. Further tests and improvements are applied to one of these methods. In addition, we attempt to make this method suitable for low-resolution vertical profiles, like those from the outputs of reanalysis methods or from the World Meteorological Organization's (WMO) Global Telecommunication System. The perfect agreement, even when using low-resolution profiles, can be improved by up to 67% (plus 25% of the approximate agreement) if the thresholds for a moist layer to become a cloud layer are modified to minimize false negatives with the current data set, thus improving overall agreement.

  8. Structural and Molecular Mechanism of CdpR Involved in Quorum-Sensing and Bacterial Virulence in Pseudomonas aeruginosa.

    Directory of Open Access Journals (Sweden)

    Jingru Zhao

    2016-04-01

    Full Text Available Although quorum-sensing (QS systems are important regulators of virulence gene expression in the opportunistic human pathogen Pseudomonas aeruginosa, their detailed regulatory mechanisms have not been fully characterized. Here, we show that deletion of PA2588 resulted in increased production of pyocyanin and biofilm, as well as enhanced pathogenicity in a mouse model. To gain insights into the function of PA2588, we performed a ChIP-seq assay and identified 28 targets of PA2588, including the intergenic region between PA2588 and pqsH, which encodes the key synthase of Pseudomonas quinolone signal (PQS. Though the C-terminal domain was similar to DNA-binding regions of other AraC family members, structural studies revealed that PA2588 has a novel fold at the N-terminal region (NTR, and its C-terminal HTH (helix-turn-helix domain is also unique in DNA recognition. We also demonstrated that the adaptor protein ClpS, an essential regulator of ATP-dependent protease ClpAP, directly interacted with PA2588 before delivering CdpR to ClpAP for degradation. We named PA2588 as CdpR (ClpAP-degradation and pathogenicity Regulator. Moreover, deletion of clpP or clpS/clpA promotes bacterial survival in a mouse model of acute pneumonia infection. Taken together, this study uncovered that CdpR is an important QS regulator, which can interact with the ClpAS-P system to regulate the expression of virulence factors and pathogenicity.

  9. Quality indicators and shelf life of red octopus (Octopus maya in chilling storage

    Directory of Open Access Journals (Sweden)

    Mariel GULLIAN-KLANIAN

    2016-01-01

    Full Text Available Abstract There are no precedents concerning the quality of Octopus maya during chilled storage. This study evaluated the shelf life of the red octopus in chilling storage (4oC and the correlation of the sensory quality index with microbiological counting and the biochemical indicators (hypoxanthine, histamine and volatile amines. A total of 112 whole raw octopi (average weight of 896 g were randomly selected from seven batches and exposed to 4°C for 18, 24, 48, 72, 84, 96, and 100 h. The histamine concentration (91.7%, followed by the counts of psychrotrophic bacteria (5.5% and hypoxanthine (2.2%, were the predictors from the redundancy analysis that better explained the changes taking place during the chilling hours. After 72 h of chilling, the microbial count was determined to be log 4.7 CFU/g, and the octopus samples were classified as B quality (minor sensory quality defects based on the sensory quality scale. Although the samples were not classified as unacceptable at 100 h of refrigeration by the sensory index, the level of histamine reached the defect action level (5 mg/100 g as ruled by the International Food Safety Authorities. The shelf life of the red octopus in chilling storage was predicted to be 119 h.

  10. Determination of Chilling and Heat Requirements of Pistachio (Pistacia vera L.) Cultivars

    Institute of Scientific and Technical Information of China (English)

    Majid Rahemi; Zahra Pakkish

    2009-01-01

    Determination of chilling and heat requirements of pistachio (Pistacia vera L.) cultivars is important for satisfactory growth and development, particularly when large-scale commercial production is desired. This experiment was conducted to determine chilling requirement inducing vegetative and flower buds of Kalle-Ghuchi, Owhadi, Ahmad-Ahgaei, and Akbari pistachio. Shoots with enough vegetative and flower buds were taken from pistachio trees during autumn 2007 and 2008 when temperature reached to≤15℃. Cuttings with flower buds were kept under (5±1)℃ for 0, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, 1100, 1150, 1200, 1250, and 1300 h, respectively, and cuttings with vegetative buds were kept at 51℃ until 1 500 h. The results indicated that pistachio eultivars requite chilling time between 750-1 400 h and heat requirements between 8 852-15 420 growing degree hours (GDH). Consequently, Kalle-Ghuehi had the lowest chilling (750-950 h), and heat (8 852-9 768 GDH) requirements, Ahmad-Aghaei and Owhadi had intermediate (1 000-1 250 h, 10 656-13 320 GDH) and Akbari had the highest chilling (1 200-1 400 h) and heat (11 863-15420 GDH) requirement.

  11. Effect of Polyamine Priming on Chilling Tolerance of Lolium perenne during Seed Imbibition

    Institute of Scientific and Technical Information of China (English)

    Yingfen WANG; Puchang WANG; Jiahai WU; Lili ZHAO; Bentian MO; Jun LI

    2012-01-01

    [Objective] This study aimed to investigate the effect of potyamine priming on physiological and biochemical variations of Lolium perenne embryos and seed germination. [Method] With annual Lolium perenne (Diamond T and Grazing-8000) as experimental materials, after priming with 0.5 mmol/L putrescine (Put), spermidine (Spd) and spermine (Spm) for 24 h and chilling imbibition at 5 ℃ for 12, 24, 36 and 48 h, the effect of Put, Spd and Spm priming on chilling tolerance and germination ability of annual Lolium perenne seeds during imbibition was investigated. [Result] Put, Spd and Spm priming improved the activities of peroxidase (POD), catalase (CAT), superoxide dismutase (SOD) and ascorbate peroxidase (APX) and content of soluble protein content under low temperature stress, significantly in-creased the germination rate, and shortened the average germination duration. After chilling imbibition for 48 h, compared with the control, the average germination rate of annual Lolium perenne seeds was improved by 15.5% and 12.0% after Put, Spd and Spm priming, and the average germination duration was shortened by 1.21 and 1.14 d. During seed imbibition, the chilling tolerance of Grazing-8000 was stronger than that of Diamond T. Overall, Put, Spd and Spm treatment could increase the chilling tolerance of annual Lolium perenne seeds during imbibition, and improve the germination ability of seeds under low temperature stress. [Conclusion] Results of this study provided theoretical basis for the application of seed priming technology in the production of annual ryegrass.

  12. Identification of Clathrate Hydrates, Hexagonal Ice, Cubic Ice, and Liquid Water in Simulations: the CHILL+ Algorithm.

    Science.gov (United States)

    Nguyen, Andrew H; Molinero, Valeria

    2015-07-23

    Clathrate hydrates and ice I are the most abundant crystals of water. The study of their nucleation, growth, and decomposition using molecular simulations requires an accurate and efficient algorithm that distinguishes water molecules that belong to each of these crystals and the liquid phase. Existing algorithms identify ice or clathrates, but not both. This poses a challenge for cases in which ice and hydrate coexist, such as in the synthesis of clathrates from ice and the formation of ice from clathrates during self-preservation of methane hydrates. Here we present an efficient algorithm for the identification of clathrate hydrates, hexagonal ice, cubic ice, and liquid water in molecular simulations. CHILL+ uses the number of staggered and eclipsed water-water bonds to identify water molecules in cubic ice, hexagonal ice, and clathrate hydrate. CHILL+ is an extension of CHILL (Moore et al. Phys. Chem. Chem. Phys. 2010, 12, 4124-4134), which identifies hexagonal and cubic ice but not clathrates. In addition to the identification of hydrates, CHILL+ significantly improves the detection of hexagonal ice up to its melting point. We validate the use of CHILL+ for the identification of stacking faults in ice and the nucleation and growth of clathrate hydrates. To our knowledge, this is the first algorithm that allows for the simultaneous identification of ice and clathrate hydrates, and it does so in a way that is competitive with respect to existing methods used to identify any of these crystals. PMID:25389702

  13. Chilling Tolerance of Cucumber During Germination is Related to Expression of Lysine Decarboxylase Gene

    Institute of Scientific and Technical Information of China (English)

    LU Ming-hui; LI Xiao-ming; CHEN Jin-feng; CHEN Long-zheng; QIAN Chun-tao

    2005-01-01

    Using cDNA-AFLP technique, a specific fragment was isolated from cucumber cultivar Changchun mici possessing chilling tolerance induced at low temperature (15℃). This fragment, named cctr 132, could not be induced in the chilling sensitive cucumber cultivar Beijing jietou. After recovering the fragment, sequencing and translating, the results of blastx and blastp in GenBank of NCBI indicated that CCTR132 had 88.37% identities and 100% positives with Oryza sativa putative lysine decarboxylase-like protein respectively, and PGGXGTXXE, the putative conserved domain of lysine decarboxylase family, was detected from CCTR132, suggesting the cucumber chilling tolerance during germination is related to the expression of the lysine decarboxylase gene.

  14. The oxidative stability of chilled and frozen pilchards used as feed for captive southern bluefin tuna

    DEFF Research Database (Denmark)

    Fitz-Gerald, C.H.; Bremner, Allan

    1998-01-01

    and flavour of cooked samples and by the chemical measures of peroxide value and levels of free fatty acids. There was considerable variability in fat content between individual fish with average content over all samples analysed in the trial being about 4 to 5%. In chilled storage, the pilchards exhibited...... obvious deterioration within two days. Substantial peroxide values were found and oxidised odours and flavours were clearly evident after 4 days' chilled storage. In frozen storage, oxidation occurred after only one month at a temperature of -20°C. This could be delayed if the fish were glazed with water...... demonstrated that the oil in the pilchards is very readily oxidised and careful handling, chilling, freezing and storage procedures need to be adopted to provide a product which is a nutritionally sound feed material for captive tuna. The demerit point scoring system was found to be a rapid evaluative...

  15. [The use of "sous vide" technology in the packaging of chilled and ready to serve food].

    Science.gov (United States)

    Zalewski, S

    1999-01-01

    As chilled precooked dishes show limited to 3-5 days shelf life several additional factors have to be applied to extend it up to 21 or even 42 days as is sometimes allowed for sous vide technology products. Those factors comprise high hygienic standards for raw materials and premises as well as technological steps and parameters that efficiently destroy microbial contamination, and do not allow for recontamination or bacterial growth. Such steps include precooking which also means pasteurisation in high vacuum or anaerobic atmosphere in sealed pouches, blast chilling, low temperature storage parameters as well as high temperature of reheating process and quick serving procedures. Paper specifies parameters for each technological steps and presents microbiological requirements for final products. Sous vide technology allows for good quality and high nutritional value in soups, meats in sauces and stewed vegetables. It is used for individual consumer in chilled "ready to eat" line dishes in supermarkets and supplies such dishes for catering units. PMID:10523935

  16. Dynamic Sensing Performance of a Point-Wise Fiber Bragg Grating Displacement Measurement System Integrated in an Active Structural Control System

    Directory of Open Access Journals (Sweden)

    Chien-Ching Ma

    2011-12-01

    Full Text Available In this work, a fiber Bragg grating (FBG sensing system which can measure the transient response of out-of-plane point-wise displacement responses is set up on a smart cantilever beam and the feasibility of its use as a feedback sensor in an active structural control system is studied experimentally. An FBG filter is employed in the proposed fiber sensing system to dynamically demodulate the responses obtained by the FBG displacement sensor with high sensitivity. For comparison, a laser Doppler vibrometer (LDV is utilized simultaneously to verify displacement detection ability of the FBG sensing system. An optical full-field measurement technique called amplitude-fluctuation electronic speckle pattern interferometry (AF-ESPI is used to provide full-field vibration mode shapes and resonant frequencies. To verify the dynamic demodulation performance of the FBG filter, a traditional FBG strain sensor calibrated with a strain gauge is first employed to measure the dynamic strain of impact-induced vibrations. Then, system identification of the smart cantilever beam is performed by FBG strain and displacement sensors. Finally, by employing a velocity feedback control algorithm, the feasibility of integrating the proposed FBG displacement sensing system in a collocated feedback system is investigated and excellent dynamic feedback performance is demonstrated. In conclusion, our experiments show that the FBG sensor is capable of performing dynamic displacement feedback and/or strain measurements with high sensitivity and resolution.

  17. Effects of chlorine or chlorine dioxide during immersion chilling on recovery of bacteria from broiler carcasses and chiller water

    Science.gov (United States)

    A study was conducted to determine the microbiological impact of immersion chilling broiler carcasses with chlorine or chlorine dioxide. Eviscerated, pre-chill commercial broiler carcasses were cut into left and right halves along the keel bone, and each half was rinsed (HCR) in 100 mL of 0.1% pept...

  18. Freshness assessment of thawed and chilled cod fillets packed in modified atmosphere using near-infrared spectroscopy

    DEFF Research Database (Denmark)

    Bøknæs, Niels; Jensen, K.N.; Andersen, Charlotte Møller;

    2002-01-01

    ). Systematic differences in the NIR measurements on minced cod fillets were primarily due to the chill storage duration (days at 2 degreesC) on thawed-chilled MAP fillets. PLSR models based on wavelengths selected by a new Jack-knife method resulted in a correlation coefficient of 0.90 between measured...

  19. RNA Expression and Post-Transcriptional Editing Analyses of Cucumber Plastids Reveals Genetic Differences Associated with Chilling Tolerance

    Science.gov (United States)

    Tolerance to chilling injury in cucumber (Cucumis sativus L.) is associated with three plastomic single nucleotide polymorphisms (ptSNPs) at bp positions 4,813, 56,561, and 126,349 that are co-inherited. An understanding of the genetic expression of these ptSNPs as a response to chilling is critical...

  20. Cold-induced sudden reversible lowering of in vivo chlorophyll fluorescence after saturating light pulses : a sensitive marker for chilling susceptibility.

    Science.gov (United States)

    Larcher, W; Neuner, G

    1989-03-01

    In chilling-sensitive plants (Glycine max, Saintpaulia ionantha, Saccharum officinarum) a sudden reversible drop in chlorophyll fluorescence occurs during photosynthetic induction immediately following saturating light pulses at low temperatures in the range 4 to 8 degrees C. A comparison of two soybean cultivars of different chilling sensitivities revealed that this phenomenon, termed lowwave, indicates specific thresholds of low temperature stress. Its occurrence under controlled chilling can be regarded as a quantitative marker for screening chilling susceptibility in angiosperms. PMID:16666615

  1. Transcriptome Analysis of Pepper (Capsicum annuum Revealed a Role of 24-epibrassinolide in Response to Chilling

    Directory of Open Access Journals (Sweden)

    Li Jie

    2016-08-01

    Full Text Available Brassinosteroids (BRs have positive effects on many processes during plant growth, development, and various abiotic stress responses. However, little information is available regarding the global gene expression of BRs in response to chilling stress in pepper. In this study, we used RNA sequencing to determine the molecular roles of 24-epibrassinolide (EBR during a chilling stress response. There were 39,829 transcripts, and, among them, 656 were differently-expressed genes (DEGs following EBR treatment (Chill+EBR compared with the control (Chill only, including 335 up-regulated and 321 down-regulated DEGs. We selected 20 genes out of the 656 DEGs for RT-qPCR analysis to confirm the RNA-Seq. Based on GO enrich and KEGG pathway analysis, we found that photosynthesis was significantly up-enriched in biological processes, accompanied by significant increases in the net photosynthetic rate (Pn, Fv/Fm and chlorophyll content. Furthermore, the results indicate that EBR enhanced endogenous levels of salicylic acid (SA and jasmonic acid (JA while suppressing the ethylene (ETH biosynthesis pathway, suggesting that BRs function via a synergistic cross-talk with SA, JA and ETH signaling pathways in response to chilling stress. In addition, EBR induced cellulose synthase-like protein and UDP-glycosyltransferase, suggesting a contribution to the formation of cell wall and hormone metabolism. EBR also triggered the calcium signaling transduction in cytoplasm, and activated the expression of cellular redox homeostasis related genes, such as GSTX1, PER72, and CAT2. This work, therefor, identified the specific genes showed different expression patterns in EBR-treated pepper and associated with the processes of hormone metabolism, redox, signaling, transcription and defense. Our study provides the first evidence of the potent roles of BRs, at the transcription level, to induce the tolerance to chilling stress in pepper as a function of the combination of the

  2. Microbiological shelf life of fresh, chilled reindeer meat (M. longissimus dorsi

    Directory of Open Access Journals (Sweden)

    Eva Wiklund

    2011-04-01

    Full Text Available In this pilot study loin muscles (M. longissimus dorsi from six reindeer calves (aged 4 months were used to determine shelf life of fresh, chilled reindeer meat stored at +4 °C, measured as microbiological quality (aerobic microorganisms and Escherichia coli. The loins were collected at boning 3 days post slaughter and divided in five pieces that were randomly assigned to five different storage times; sampling directly after packaging and after chilled storage for 2, 3, 4 and 5 weeks at +4 °C. Samples were vacuum packaged and transported chilled to Hjortens Laboratory in Östersund, Sweden (accredited by SWEDAC according to SS-EN ISO/IEC 17025:2005 for food analysis where the storage, microbiological sampling and analysis took place according to the protocols of Nordic Committee on Food Analysis (NMKL. The total amount of aerobic microorganisms at the first sampling directly after packaging (three days post slaughter was 3.4 ± 0.3 log10 CFU/g. After two and three weeks of vacuum packaged chilled storage at +4°C the microbiological quality of the samples was on the border-line to poor (6.8 ± 0.3 log10 CFU/g. At four and five weeks of chilled storage the levels of aerobic microorganisms were significantly highest (P≤0.05 and the limit for acceptable quality of 7 log10 CFU/g aerobic bacteria had been passed (7.3 ± 0.3 log10 CFU/g and 7.8 ± 0.3 log10 CFU/g, respectively. Very few of the reindeer meat samples were contaminated with Escherichia coli bacteria. The results from the present pilot study suggest that storage time for vacuum packaged fresh, chilled reindeer meat should not exceed 3 weeks at a temperature of +4 °C.

  3. The benefits of liposomes for chilling canine sperm for 4 days at 4°C.

    Science.gov (United States)

    Belala, Redha; Delay, Juliette; Amirat, Lamia; Ropers, Marie-Hélène; Le Guillou, Jocya; Anton, Marc; Schmitt, Eric; Thorin, Chantal; Michaud, Sandrine; Kaidi, Rachid; Tainturier, Daniel; Bencharif, Djemil

    2016-05-01

    This study comprises 3 experiments exploring the possible benefits and mechanism of action of liposomes for chilling (4°C) canine sperm over a period of 4 days. In the first experiment, 20 ejaculates collected from 5 Beagle dogs were chilled in an extender containing 6% low density lipoproteins (LDL) (Control), or one of 7 extenders containing different concentrations (2, 4, 6, 8, 10, 15, 20%) of liposomes (LIPO). These ejaculates were chilled over 4 days and motility was assessed daily using a Hamilton Thorne analyzer (HTM-IVOS, 14.0). The 2% LIPO obtained the best results (p=0.038) after four days (72.55% motile spermatozoa and 31.4% progressive spermatozoa). In experiment 2, 10 ejaculates were collected from same 5 dogs and chilled in 6% LDL or 2% LIPO-based extenders. Sperm integrity characteristics were assessed prior to refrigeration and every 48h for four days (D0, D2, and D4). Acrosome integrity was assessed using the FITC-PSA test (Fluorescein IsoThiocyanate-Pisum Sativum Agglutinin), plasma membrane (PM) integrity using both the hypo-osmotic swelling test (HOSt) and SYBR14/Propidium Iodide test (SYBR14/PI), and DNA integrity using the Acridine-Orange test (AO). The 2% LIPO extender provided equivalent preservation of sperm integrity parameters to the reference extender (6% LDL). In experiment 3, a Langmuir-Blodgett trough was used to evaluate the mechanistic interactions between LDL, LIPO, prostatic fluid, and the canine spermatozoal membrane during chilling. Results indicate that LDL and LIPO interact differently with the biomimetic membrane. The most likely conclusion of these findings is that LDL and liposomes employ different protective mechanisms during the chilling (4°C) of canine spermatozoa. PMID:26952759

  4. Transcriptome Analysis of Pepper (Capsicum annuum) Revealed a Role of 24-Epibrassinolide in Response to Chilling

    Science.gov (United States)

    Li, Jie; Yang, Ping; Kang, Jungen; Gan, Yantai; Yu, Jihua; Calderón-Urrea, Alejandro; Lyu, Jian; Zhang, Guobin; Feng, Zhi; Xie, Jianming

    2016-01-01

    Brassinosteroids (BRs) have positive effects on many processes during plant growth, development, and various abiotic stress responses. However, little information is available regarding the global gene expression of BRs in response to chilling stress in pepper. In this study, we used RNA sequencing to determine the molecular roles of 24-epibrassinolide (EBR) during a chilling stress response. There were 39,829 transcripts, and, among them, 656 were differently-expressed genes (DEGs) following EBR treatment (Chill+EBR) compared with the control (Chill only), including 335 up-regulated and 321 down-regulated DEGs. We selected 20 genes out of the 656 DEGs for RT-qPCR analysis to confirm the RNA-Seq. Based on GO enrich and KEGG pathway analysis, we found that photosynthesis was significantly up-enriched in biological processes, accompanied by significant increases in the net photosynthetic rate (Pn), Fv/Fm, and chlorophyll content. Furthermore, the results indicate that EBR enhanced endogenous levels of salicylic acid (SA) and jasmonic acid (JA) while suppressing the ethylene (ETH) biosynthesis pathway, suggesting that BRs function via a synergistic cross-talk with SA, JA, and ETH signaling pathways in response to chilling stress. In addition, EBR induced cellulose synthase-like protein and UDP-glycosyltransferase, suggesting a contribution to the formation of cell wall and hormone metabolism. EBR also triggered the calcium signaling transduction in cytoplasm, and activated the expression of cellular redox homeostasis related genes, such as GSTX1, PER72, and CAT2. This work, therefor, identified the specific genes showed different expression patterns in EBR-treated pepper and associated with the processes of hormone metabolism, redox, signaling, transcription, and defense. Our study provides the first evidence of the potent roles of BRs, at the transcription level, to induce the tolerance to chilling stress in pepper as a function of the combination of the

  5. A combined top-down/bottom-up approach to structuring multi-sensing zones on a thin film and the application to SPR sensors

    Science.gov (United States)

    Choi, Youngbo; Hyang Shin, So; Hong, Surin; Kim, Younghun

    2016-08-01

    The development of a thin film with well-defined metallic micro/nanostructures, diverse surface functionalities, and superior electronic/optical properties has been a great challenge to researchers seeking an efficient method for the detection of various analytes in chemical and biological sensing applications. Herein, we report a facile and effective approach to the fabrication of an ordered gold island pattern on a glass substrate with contrasted chemical functionalities, which can provide spatially separated sensing zones for multi-detection. In the proposed method, the combination between the micro/nano-imprint lithography and sequential self-assembly approaches exhibited synergistic effects that allowed well-defined structuring and easy surface functionalization in separated sensing zones. Via imprint lithography, the uniform gold islands/glass structure was successfully fabricated from a readily available gold-coated glass film. In addition, a sequential self-assembling strategy and specific chemical-substrate interactions, such as thiol-gold and silane-glass, enabled the surfaces of gold islands and exposed portions of the glass substrate with contrasting chemical functionalities—SH-functionalized gold islands and NH2-functionalized glass substrate. A proof-of-concept experiment for the multi-detection of heavy metal ions (Hg2+ and Cu2+) in an aqueous media was also successfully conducted using the dual-functionalized gold islands/glass structure and surface plasmon resonance measurements. The SH groups on the gold islands and the NH2 groups on the glass substrate functioned as spatially separated and selective receptors for Hg2+ and Cu2+ ions, respectively. Therefore, both the detection and quantification of Hg2+ and Cu2+ ions could be achieved using a single sensing substrate.

  6. Effect of irradiation and storage time on lipid oxidation of chilled pork

    Science.gov (United States)

    Cheng, Anwei; Wan, Fachun; Xu, Tongcheng; Du, Fangling; Wang, Wenliang; Zhu, Qingjun

    2011-03-01

    The effects of γ-irradiation with different doses (0, 2, 4, 6, 8 and 10 kGy) and storage time (0-30 days) on the lipid oxidation of chilled pork and the combined effect of irradiation and antioxidant on the lipid oxidative stability during storage at 4 °C were investigated. The results indicated that irradiation treatment increased lipid oxidation, measured as peroxide (PV) and thiobarbituric acid reactive substance (TBARS) values. Lipid oxidation was increased with the increase in storage time. The addition of tea polyphenol (TP) was effective in controlling the lipid oxidation of chilled pork after irradiation during cold storage.

  7. Alternative Layouts for the Carbon Capture with the Chilled Ammonia Process

    DEFF Research Database (Denmark)

    Valenti, Gianluca; Bonalumi, Davide; Fosbøl, Philip Loldrup;

    2013-01-01

    Many alternatives are being investigated for the carbon capture, but none appears to have been proved as the choice for full-scale applications. This work considers the Chilled Ammonia Process for coal-fired Ultra Super Critical power plants. Three layouts are simulated with Aspen Plus and the Ex......Many alternatives are being investigated for the carbon capture, but none appears to have been proved as the choice for full-scale applications. This work considers the Chilled Ammonia Process for coal-fired Ultra Super Critical power plants. Three layouts are simulated with Aspen Plus...

  8. The Relationship Between Heat-induced Chilling Tolerance and Endogenous ABA Levels in Mangoes

    Institute of Scientific and Technical Information of China (English)

    ZHU Shi-jiang; JI Zuo-liang

    2002-01-01

    Heating "Zhihua" mangoes (Mangifera indica L. cv. Zhihua) in hot air at 38℃ for 12hours significantly reduced the development of chilling injury following storage for 12days at 2℃. Prolonging the heating up to 72hours acquired similar results. During the 12 days' storage at 2℃ following heating for 72hours, the membrane leakage of the mango peels showed little change, while it increased with time for the control fruits, and the endogenous ABA levels in the heated fruits were higher than that in the control. These results indicated that higher ABA rates were linked with stronger chilling tolerance in mangoes.

  9. Analytical Method for Differentiation of Chilled and Frozen-Thawed Chicken Meat

    OpenAIRE

    Ivanova Ivelina; Ivanov Galin; Shikov Vasil; Ivanova Snezhana

    2014-01-01

    : Chilled and frozen chicken breast and thigh meat were stored at +4±1 oC and - 20±1 oC, respectively. Maillard reaction between ribose and meat proteins of the chicken samples was initiated. The changes in the ribose-induced Maillard reaction rate during chilled and frozen storage of chicken meat were evaluated on the bases of corrected absorbance values (A420*) and bovine melanoidin equivalent values (mg BME/g). Application of BME as a measure of ribose-induced Maillard reaction rate enable...

  10. Cook-chill, cook-freeze, cook-hold, sous vide: risks for hospital patients?

    Science.gov (United States)

    Wilkinson, P J; Dart, S P; Hadlington, C J

    1991-06-01

    Changes in eating habits and developments in food technology are occurring at the same time as an upward trend in foodborne infection in Britain. Vulnerable people such as the elderly and hospital patients are increasingly likely to consume food produced by new systems such as 'cook-chill' and 'cuisson sous vide'. The microbiological hazards of these systems are assessed as negligible, provided that production is controlled by appropriate methods such as the hazard analysis critical control point (HACCP) approach. The occurrence and control of bacterial contamination in a hospital cook-chill system is reviewed in this context.

  11. Cook-chill, cook-freeze, cook-hold, sous vide: risks for hospital patients?

    Science.gov (United States)

    Wilkinson, P J; Dart, S P; Hadlington, C J

    1991-06-01

    Changes in eating habits and developments in food technology are occurring at the same time as an upward trend in foodborne infection in Britain. Vulnerable people such as the elderly and hospital patients are increasingly likely to consume food produced by new systems such as 'cook-chill' and 'cuisson sous vide'. The microbiological hazards of these systems are assessed as negligible, provided that production is controlled by appropriate methods such as the hazard analysis critical control point (HACCP) approach. The occurrence and control of bacterial contamination in a hospital cook-chill system is reviewed in this context. PMID:1679787

  12. Structure/Function Analysis of the Quorum-sensing Regulator EsaR from the Plant Pathogen Pantoea stewartii

    OpenAIRE

    Schu, Daniel Joseph

    2009-01-01

    Pantoea stewartii subsp. stewarti is the causative agent of Stewartâ s wilt disease in maize. Disease symptoms develop after the bacteria grow to high cell densities in the plant xylem and secrete an abundance of exopolysaccharide (EPS). EPS production is regulated by quorum sensing. Two regulatory proteins are key to the process of quorum sensing, the LuxI and LuxR homologues EsaI and EsaR. Most LuxR homologues function as activators of transcription in the presence of their cognate acylate...

  13. Changesin Myoglobin of Big Eye Tuna During Chilling Storage

    Directory of Open Access Journals (Sweden)

    Stevi Imelda Murniati Wodi

    2015-01-01

    Full Text Available Big eye tuna (Thunnus obesus is one of the species of tuna which is have some value added such as have potential to improve animal protein sources, have high economic values as well as an export commodity.Mishandling and misapplication of high temparatures on the tuna handling at the tropics and sub tropics climate was significantly decreasing the value of myoglobin and affecting the solubility of protein. Myoglobin is a globular protein that have small molecular weight size and it was an important factor for determining the quality of meat and influencing factors of purchasing power by the consumer. The purpose of this experiments is to determining the changes of myoglobin content and the water soluble proteins content at some parts of big eye tuna in 9 days chilling temperatures. The portion which is analized was the ventral area, dorsal area and tail area. Myoglobin content in all portion above, both light and dark meat was analized. The results shows the decreased value of myoglobin content from first handling (day zero until day ninth (days 9th experiment. Each myoglobin contentfrom white meat at at ventral, dorsal and tail meat was decreased from 121.68 mg/100 into 41.35 mg/100, 148.2 mg/100g into 52.01 mg/100g, 105.16 mg/100g into 31.34 gr/100gram, after day ninth. The myoglobin content from dark meat at ventral, dorsal and tail meat, was decreased, too ; from 418.64 mg/100 gr into 121.01 mg/100 g, 446.21 mg/100 g into 58.34 mg/100 r and 145.65 mg/100 gr into 87.98 mg/100g after day ninth.Water soluble protein was derived into protein bands with molecular weight 15,4 kDa and 14 kDa. Its suspected as the myoglobin protein. The molecular weight difference was caused from degradation of protein during the storage.Keywords: Big eye tuna, meat, storage, myoglobin

  14. Remote Sensing

    CERN Document Server

    Khorram, Siamak; Koch, Frank H; van der Wiele, Cynthia F

    2012-01-01

    Remote Sensing provides information on how remote sensing relates to the natural resources inventory, management, and monitoring, as well as environmental concerns. It explains the role of this new technology in current global challenges. "Remote Sensing" will discuss remotely sensed data application payloads and platforms, along with the methodologies involving image processing techniques as applied to remotely sensed data. This title provides information on image classification techniques and image registration, data integration, and data fusion techniques. How this technology applies to natural resources and environmental concerns will also be discussed.

  15. Structural insights into a novel interkingdom signaling circuit by cartography of the ligand-binding sites of the homologous quorum sensing LuxR-family.

    Science.gov (United States)

    Covaceuszach, Sonia; Degrassi, Giuliano; Venturi, Vittorio; Lamba, Doriano

    2013-01-01

    Recent studies have identified a novel interkingdom signaling circuit, via plant signaling molecules, and a bacterial sub-family of LuxR proteins, bridging eukaryotes and prokaryotes. Indeed pivotal plant-bacteria interactions are regulated by the so called Plant Associated Bacteria (PAB) LuxR solo regulators that, although closely related to the quorum sensing (QS) LuxR family, do not bind or respond to canonical quorum sensing N-acyl homoserine lactones (AHLs), but only to specific host plant signal molecules. The large body of structural data available for several members of the QS LuxR family complexed with different classes of ligands (AHLs and other compounds), has been exploited to dissect the cartography of their regulatory domains through structure-based multiple sequence alignments, structural superimposition and a comparative analysis of the contact residues involved in ligand binding. In the absence of experimentally determined structures of members of the PAB LuxR solos subfamily, an homology model of its prototype OryR is presented, aiming to elucidate the architecture of its ligand-binding site. The obtained model, in combination with the cartography of the regulatory domains of the homologous QS LuxRs, provides novel insights into the 3D structure of its ligand-binding site and unveils the probable molecular determinants responsible for differences in selectivity towards specific host plant signal molecules, rather than to canonical QS compounds.

  16. Fly's proprioception-inspired micromachined strain-sensing structure: idea, design, modeling and simulation, and comparison with experimental results

    Energy Technology Data Exchange (ETDEWEB)

    Wicaksono, D H B [Department of Microelectronics, Delft University of Technology, Mekelweg 4, Delft, Zuid-Holland 2628CD (Netherlands); Zhang, L-J [Department of Microelectronics, Delft University of Technology, Mekelweg 4, Delft, Zuid-Holland 2628CD (Netherlands); Pandraud, G [Department of Microelectronics, Delft University of Technology, Mekelweg 4, Delft, Zuid-Holland 2628CD (Netherlands); French, P J [Department of Microelectronics, Delft University of Technology, Mekelweg 4, Delft, Zuid-Holland 2628CD (Netherlands); Vincent, J F V [Department of Mech. Engineering, Bath University Bath, BA2 7AY (United Kingdom)

    2006-04-01

    A new strain-sensing structure inspired from insect's (especially the Fly) propricoception sensor is devised. The campaniform sensillum is a strain-sensing microstructure with very high sensitivity despite its small dimension (diameter {approx}10 {mu}m in a relatively stiff material of insect's exocuticle (E = {approx}10{sup 9} Pa). Previous work shows that the high sensitivity of this structure towards strain is due to its membrane-in-recess- and strainconcentrating-hole-features. Based on this inspiration, we built similar structure using silicon micromachining technology. Then a simple characterisation setup was devised. Here, we present briefly, finite-element modeling and simulation based on this actual sample preparation for the characterisation. As comparison and also to understand mechanical features responsible for the strain-sensitivity, we performed the modeling on different mechanical structures: bulk chunk, blind-hole, through-hole, surface membrane, and membrane-in-recess. The actual experimental characterisation was performed previously using optical technique to membrane in-recess micromachined Si structure. The FEM simulation results confirm that the bending stress and strain are concentrated in the hole-vicinity. The membrane inside the hole acts as displacement transducer. The FEM is in conformity with previous analytical results, as well as the optical characterisation result. The end goal is to build a new type MEMS strain sensor.

  17. Genomic HIV RNA induces innate immune responses through RIG-I-dependent sensing of secondary-structured RNA

    NARCIS (Netherlands)

    Berg, R.K.; Melchjorsen, J.; Rintahaka, J.; Diget, E.; Søby, S.; Horan, K.A.; Gorelick, R.J.; Matikainen, S.; Larsen, C.S.; Ostergaard, L.; Paludan, S.R.; Mogensen, T.H.

    2012-01-01

    BACKGROUND: Innate immune responses have recently been appreciated to play an important role in the pathogenesis of HIV infection. Whereas inadequate innate immune sensing of HIV during acute infection may contribute to failure to control and eradicate infection, persistent inflammatory responses la

  18. Hydrothermal Synthesis of Bi6S2O15 Nanowires: Structural, in situ EXAFS, and Humidity-Sensing Studies

    DEFF Research Database (Denmark)

    Zhou, Y.; Grunwaldt, Jan-Dierk; Krumeich, F.;

    2010-01-01

    Sensing oxysulfates: A new type of bismuth oxysulfate nanowire emerges from the straightforward hydrothermal reaction of Bi2O3 and K2SO4. The formation pathway of this versatile material is monitored with in situ QEXAFS techniques. The high-aspect-ratio nanorods display promising features...

  19. Remote sensing; Fernerkundung

    Energy Technology Data Exchange (ETDEWEB)

    Glaessler, C.

    2001-07-01

    The potential of different multitemporal and multispectral airborne and spaceborne remote sensing methods for assessment and monitoring of the lignite open-cast mining areas are discussed in this chapter. Emphasis is placed on the successful use of different remote sensing data in variable vegetation structures for dumped sediments with different mineralogical and geochemical properties and for hydrochemical properties of the residual lakes. Multiple remote sensing data are a cost and time efficient tool for the assessment of environmental impacts, supervising of reclamation activities as well as for long term monitoring of the mining area. The airborne data are well suited for large scale detailed research and mapping in smaller sites and the satellite data for the overview scale 1:50 000. An integrated remote sensing-GIS-system including all field and lab data, DTM and other graphical data, improve the results of the remote sensing data classification for the lignite mining region in Central Germany and the Lausitz. (orig.)

  20. Accurate Characterization of Winter Precipitation Using In-Situ Instrumentation, CSU-CHILL Radar, and Advanced Scattering Methods

    Science.gov (United States)

    Newman, A. J.; Notaros, B. M.; Bringi, V. N.; Kleinkort, C.; Huang, G. J.; Kennedy, P.; Thurai, M.

    2015-12-01

    We present a novel approach to remote sensing and characterization of winter precipitation and modeling of radar observables through a synergistic use of advanced in-situ instrumentation for microphysical and geometrical measurements of ice and snow particles, image processing methodology to reconstruct complex particle three-dimensional (3D) shapes, computational electromagnetics to analyze realistic precipitation scattering, and state-of-the-art polarimetric radar. Our in-situ measurement site at the Easton Valley View Airport, La Salle, Colorado, shown in the figure, consists of two advanced optical imaging disdrometers within a 2/3-scaled double fence intercomparison reference wind shield, and also includes PLUVIO snow measuring gauge, VAISALA weather station, and collocated NCAR GPS advanced upper-air system sounding system. Our primary radar is the CSU-CHILL radar, with a dual-offset Gregorian antenna featuring very high polarization purity and excellent side-lobe performance in any plane, and the in-situ instrumentation site being very conveniently located at a range of 12.92 km from the radar. A multi-angle snowflake camera (MASC) is used to capture multiple different high-resolution views of an ice particle in free-fall, along with its fall speed. We apply a visual hull geometrical method for reconstruction of 3D shapes of particles based on the images collected by the MASC, and convert these shapes into models for computational electromagnetic scattering analysis, using a higher order method of moments. A two-dimensional video disdrometer (2DVD), collocated with the MASC, provides 2D contours of a hydrometeor, along with the fall speed and other important parameters. We use the fall speed from the MASC and the 2DVD, along with state parameters measured at the Easton site, to estimate the particle mass (Böhm's method), and then the dielectric constant of particles, based on a Maxwell-Garnet formula. By calculation of the "particle-by-particle" scattering

  1. Georgia Institute of Technology chilled water system evaluation and master plan

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-05-15

    As the host of the Olympic Village for the 1996 Atlanta Olympics, Georgia Tech has experienced a surge in construction activities over the last three years. Over 1.3 million square feet of new buildings have been constructed on the Georgia Tech campus. This growth has placed a strain on the Georgia Tech community and challenged the facilities support staff charged with planning and organizing utility services. In concert with Olympic construction, utility planners have worked to ensure long term benefits for Georgia Tech facilities while meeting the short term requirements of the Olympic Games. The concentration of building construction in the northwest quadrant of the campus allowed planners to construct a satellite chilled water plant to serve the needs of this area and provide the opportunity to integrate this section of the campus with the main campus chilled water system. This assessment and master plan, funded in part by the US Department of Energy, has evaluated the chilled water infrastructure at Georgia Tech, identified ongoing problems and made recommendations for long term chilled water infrastructure development and efficiency improvements. The Georgia Tech office of Facilities and RDA Engineering, Inc. have worked together to assemble relevant information and prepare the recommendations contained in this document.

  2. Texture evolution of continuous cast and direct chill cast AA 3003 aluminum alloys during cold rolling

    International Nuclear Information System (INIS)

    The texture evolution of continuous cast (CC) and direct chill cast (DC) AA 3003 aluminum alloys during cold rolling was investigated by X-ray diffraction. The relationship between texture volume fractions and rolling true strain was described quantitatively by mathematical formulae. The effect of processing method (CC vs. DC) on texture evolution was determined

  3. Can chilling tolerance of C4 photosynthesis in Miscanthus be transferred to sugarcane?

    Science.gov (United States)

    The goal of this study was to investigate if chilling tolerance of C4 photosynthesis in Miscanthus can be transferred to sugarcane. Net leaf CO2 uptake (Asat) and the maximum operating efficiency of photosystem II ('PSII) were measured in warm conditions (25 °C/20 °C), and then during and following ...

  4. Different responses of tobacco antioxidant enzymes to light and chilling stress

    NARCIS (Netherlands)

    Gechev, T; Willekens, H; Van Montagu, M; Inze, D; Van Camp, W; Toneva, [No Value; Minkov, [No Value

    2003-01-01

    The effect of elevated light treatment (25 degreesC, PPFD 360 mumol m(-2) sec(-1)) or chilling temperatures combined with elevated light (5 degreesC, PPFD 360 mumol m-2 sec-1) on the activity of six antioxidant enzymes, guaiacol peroxidases, and glutathione peroxidase (GPx, EC 1.11.1.9) protein accu

  5. Chemical additive to maximize antimicrobial effect of chlorine during pilot scale immersion chilling of broiler carcasses

    Science.gov (United States)

    A prior laboratory scale study demonstrated the potential for T-128, a proprietary blend including propylene glycol and phosphoric acid, to enhance the antimicrobial efficacy of chlorine during immersion chilling of broiler parts. The objective of the current study was to test the addition of T-128...

  6. Comparative Proteomic Analysis of Rice at Filling Stage under Chilling Stress

    Institute of Scientific and Technical Information of China (English)

    Ying Wang; Weitong Cui; Shihua Shen

    2012-01-01

    Using comparative proteomic analysis,we carried out an investigation aiming at a better understanding of the molecular mechanisms of chilling stress adaptation in rice (O.sativa L.ssp.indica cultivar 93-11) at early filling stage.The rice plants at early filling stage were exposed to 12℃ for 6 h,12 h,24 h,48 h.Analysis of the dynamic proteome profile of the uppermost internodes showed that 99 protein spots were differentially expressed during this process.Among them,45 protein spots were found to be up-regulated and 54 protein spots were down-regulated in responding to chilling stress.81 protein spots were successfully identified through MALDITOF MS and database searching.Those identified proteins were the products of 65 genes,and could be sorted into 8 functional categories.Among them,secondary metabolism related proteins such as S-adenosylmethionine synthetase were up-regulated.That lignification-related proteins were up-regulated by chilling stress indicated the uppermost internodes supporting ear would be enhanced to resist the chilling stress.

  7. Effects of chills on the solidification pattern of an axial steel cast impeller

    OpenAIRE

    Copur, M.; Turan, A; Eruslu, M. N.

    2015-01-01

    This paper presents three-dimensional simulation of transient conduction heat transfer within an axial impeller (AISI 1016), two different sizes of chills (AISI 1016), core (green sand) and mold (green sand) by using Ansys CFX. Specific heat, density and thermal conductivity of AISI 1016 steel, mold and Core materials are considered as functions of temperatures

  8. Corrosion of an aluminum alloy chilled in flowing seawater and the effect of cathodic prevention

    Energy Technology Data Exchange (ETDEWEB)

    Yabuki, A. [Graduate School of Engineering, Hiroshima University 1-4-1 Kagamiyama, Higashi-hiroshima, 739-8527 (Japan); Yasunaga, D.T. [Technical Development Group, Kobe Steel Ltd. 9-12, Kita-Shinagawa 5-chome, Shinagawa-ku, Tokyo, 141-0001 (Japan); Shibutani, T.; Shinkai, K. [Machinery and Engineering Company, Kobe Steel Ltd. 3-1, Shinhama 2-chome, Arai, Takasago, Hyogo 676-8670 (Japan)

    2007-05-15

    A new type of jet-in-slit testing apparatus for a specimen, chilled with a peltier element, was developed to investigate corrosion on the heat transfer surface of an aluminum alloy heat exchanger, in contact with a liquefaction gas at cryogenic temperature and in flowing seawater. The specimen can be chilled, even under flowing conditions, using this apparatus. Corrosion tests and polarization measurements of a specimen chilled by a peltier element were carried out in flowing seawater at various temperatures. The effect of chilling a specimen was equivalent to the effect achieved for a test in solution at a lower temperature. The process was dependent on a passive film, formed on the surface of the aluminum alloy specimen, as evidenced by polarization measurements. The extent of corrosion damage increased with increasing temperature of the solution, and showed maximum damage at high temperature. At high temperatures, erosion-corrosion was found at the central part of the specimen, but the effect of flow was negligible at low temperature. Corrosion tests for a cathodically polarized specimen were conducted under flowing conditions. Corrosion damage was accelerated by cathodic polarization at lower temperatures. (Abstract Copyright [2007], Wiley Periodicals, Inc.)

  9. FORMATION OF WEAR-RESISTANT CHROMIUM CAST IRON CASTING INTO THE CHILL MOLD

    Directory of Open Access Journals (Sweden)

    E. I. Marukovich

    2013-01-01

    Full Text Available The analysis of thermal processes of formation of castings from wearproof chromic cast irons for replaceable details of centrifugal mills and crushers is carried out. Influence of protective and dividing coverings on intensity of heating of the chill mold is investigated.

  10. Rapid chilling cannot prevent inferior pork quality caused by high preslaughter stress

    NARCIS (Netherlands)

    Hambrecht, E.; Eissen, J.J.; Klein, W.J.H.; Ducro, B.J.; Smits, C.H.M.; Verstegen, M.W.A.; Hartog, den L.A.

    2004-01-01

    The present experiment investigated whether increasing chilling rate could improve meat quality in pigs exposed to either minimal or high stress immediately preslaughter. Pigs (n = 192) were offspring of halothane-free lines. On various days, four groups of 48 pigs were processed at a commercial pla

  11. Thermal environment and air quality in office with personalized ventilation combined with chilled ceiling

    DEFF Research Database (Denmark)

    Lipczynska, Aleksandra; Kaczmarczyk, Jan; Melikov, Arsen Krikor

    2015-01-01

    The thermal environment and air quality conditions provided with combined system of chilled ceiling and personalized ventilation (PV) were studied in a simulated office room for two occupants. The proposed system was compared with total volume HVAC solutions used today, namely mixing ventilation...

  12. Arbuscular Mycorrhizal Fungus Alleviates Chilling Stress by Boosting Redox Poise and Antioxidant Potential of Tomato Seedlings

    NARCIS (Netherlands)

    Liu, Airong; Chen, Shuangchen; Wang, Mengmeng; Liu, Dilin; Chang, Rui; Wang, Zhonghong; Lin, Xiaomin; Bai, Bing; Ahammed, Golam Jalal

    2016-01-01

    The universal symbiotic associations between arbuscular mycorrhizal fungi (AMF) and plant roots remarkably stimulate plant growth, nutrient uptake, and stress responses. The present study investigated the stress ameliorative potential of the AM fungus Funneliformis mosseae against chilling in tom

  13. 77 FR 12800 - Fresh and Chilled Atlantic Salmon From Norway: Revocation of Antidumping and Countervailing Duty...

    Science.gov (United States)

    2012-03-02

    ... Norway, 76 FR 166 (January 3, 2011). As a result of its reviews, the Department found that revocation of... Duty Order, 76 FR 70409 (November 14, 2011), and Fresh and Chilled Atlantic Salmon From Norway: Final... from Norway, 77 FR 10772 (February 23, 2012) and USITC Publication 4303 (February 2012), entitled...

  14. Analisis Kecepatan Bottom Block Terhadap Struktur Mikro Produk Direct Chill Casting

    Directory of Open Access Journals (Sweden)

    Soejono Tjitro

    2004-01-01

    Full Text Available Direct chill casting process is used to produce to ingot. To produce to ingot is influenced such as bottom block speed. The objective of this research is to examine to ingot's microstructures. To use to bottom block speed is 57 mm/min and 67 mm/min. The pouring temperature of melt aluminum alloys is 750oC. Water flow rate is constant. Testing specimen is round shape which diameter and length each 70 mm and 400 mm. Microstructures on longitudinal and transversal round is investigated. Generally, microstructures of product of Direct Casting Process is non-uniform dendritic. Grain shape of 67 mm/minute bottom block rate is larger than 57 mm/minute bottom block rate. Abstract in Bahasa Indonesia : Proses Direct Chill Casting digunakan untuk menghasilkan ingot. Proses pembuatan ingot ini dipengaruhi antara lain kecepatan bottom block. Penelitian ini bertujuan untuk mengamati pengaruh kecepatan bottom block terhadap struktur mikro ingot. Kecepatan bottom block yang digunakan 57 mm/menit dan 67 mm/menit. Temperatur tuang paduan aluminium 750oC. Debit air konstan. Spesimen uji berbentuk round dengan diameter 70 mm dan panjang 400 mm. Struktur mikro yang diamati pada ke arah longitudinal dan transversal round. Struktur mikro yang dihasilkan proses direct chill casting secara umum adalah dendritik yang tidak seragam. Bentuk butir kecepatan bottom block 67 mm/menit lebih besar daripada kecepatan bottom block 57 mm/menit. Kata kunci: direct chill casting, struktur mikro, kecepatan bottom block.

  15. Influence of Oxygen Pressure on Structural and Sensing Properties of β-Ga2O3 Nanomaterial by Thermal Evaporation

    Institute of Scientific and Technical Information of China (English)

    MA Hai-Lin; FAN Duo-Wang

    2009-01-01

    We prepare the gallium oxide (β-Ga_2O_3) nanomaterials from gallium and oxygen by thermal evaporation in the argon atmosphere and research their oxygen sensing under UV illumination with different oxygen pressures. X-ray diffraction reveals that the synthesized product is monoclinic gallium oxide, it is further confirmed by electron diffraction of transmission electron microscope, and its morphology through the observation using scan-ning electron microscope reveals that β-Ga_2O_3 nanobelts with a breadth less than 100nm and length of several micrometers are synthesized under low oxygen pressure, while the nano/microbelts are synthesized under high oxygen pressure. Room-temperature oxygen sensing is tested under at 254 nm illumination and it is found that the current decreases quickly first and then slowly with oxygen pressure from low to high.

  16. Glucose Sensing

    CERN Document Server

    Geddes, Chris D

    2006-01-01

    Topics in Fluorescence Spectroscopy, Glucose Sensing is the eleventh volume in the popular series Topics in Fluorescence Spectroscopy, edited by Drs. Chris D. Geddes and Joseph R. Lakowicz. This volume incorporates authoritative analytical fluorescence-based glucose sensing reviews specialized enough to be attractive to professional researchers, yet also appealing to the wider audience of scientists in related disciplines of fluorescence. Glucose Sensing is an essential reference for any lab working in the analytical fluorescence glucose sensing field. All academics, bench scientists, and industry professionals wishing to take advantage of the latest and greatest in the continuously emerging field of glucose sensing, and diabetes care & management, will find this volume an invaluable resource. Topics in Fluorescence Spectroscopy Volume 11, Glucose Sensing Chapters include: Implantable Sensors for Interstitial Fluid Smart Tattoo Glucose Sensors Optical Enzyme-based Glucose Biosensors Plasmonic Glucose Sens...

  17. Force sensing

    OpenAIRE

    Sanders, David

    2007-01-01

    A young child can explore and learn and compensate for unknown dynamics by prodding, pushing, touching, grasping and feeling. Force sensing and software research could soon allow artificial mechanisms to do the same. Force sensing has its roots in strain gauges, piezoelectrics, Wheatstone bridges, automation, robotics, grippers and virtual reality. That force sensing research has now become commonplace and has expanded from those roots to include so much more: video games, athletic equipment,...

  18. Quality and safety of fish curry processed by sous vide cook chilled and hot filled technology process during refrigerated storage.

    Science.gov (United States)

    Shakila, R Jeya; Raj, B Edwin; Felix, N

    2012-06-01

    Fish curry, a traditional Indian dish was prepared from farmed fish Cobia (Rachycentron canadum), packaged by two different cook-chill processes namely, sous vide cook chilled and hot filled technology and held at 2 °C. Biochemical composition revealed that fish curry contained 5% protein and 6% fat. Omega-3 fatty acids, eicosapentaenoic acid (EPA) retained 55.44% while docosahexaenoic acid (DHA) retained 29% during cook-chilling process. The major fatty acids in fish curry were C18:2, C12:0, C16:0 and C18:1. Shelf-life of sous vide cook chilled and hot filled technology processed fish curry were 8 and 12 weeks, respectively. Total bacterial counts were detected after 4 weeks and 12 weeks in sous vide cook chilled and hot filled technology processes, respectively. Total staphylococci were detected in sous vide cook chilled and hot filled technology processed cobia fish curry after 4 and 12 weeks, respectively. Total bacilli, anaerobic sulfite reducing clostridia, Salmonella, and lactic acid bacteria were absent. Hot filled technology process was more efficient and could be applied for chilled fish curry preservation for 12 weeks without any safety problems.

  19. Quality and safety of fish curry processed by sous vide cook chilled and hot filled technology process during refrigerated storage.

    Science.gov (United States)

    Shakila, R Jeya; Raj, B Edwin; Felix, N

    2012-06-01

    Fish curry, a traditional Indian dish was prepared from farmed fish Cobia (Rachycentron canadum), packaged by two different cook-chill processes namely, sous vide cook chilled and hot filled technology and held at 2 °C. Biochemical composition revealed that fish curry contained 5% protein and 6% fat. Omega-3 fatty acids, eicosapentaenoic acid (EPA) retained 55.44% while docosahexaenoic acid (DHA) retained 29% during cook-chilling process. The major fatty acids in fish curry were C18:2, C12:0, C16:0 and C18:1. Shelf-life of sous vide cook chilled and hot filled technology processed fish curry were 8 and 12 weeks, respectively. Total bacterial counts were detected after 4 weeks and 12 weeks in sous vide cook chilled and hot filled technology processes, respectively. Total staphylococci were detected in sous vide cook chilled and hot filled technology processed cobia fish curry after 4 and 12 weeks, respectively. Total bacilli, anaerobic sulfite reducing clostridia, Salmonella, and lactic acid bacteria were absent. Hot filled technology process was more efficient and could be applied for chilled fish curry preservation for 12 weeks without any safety problems. PMID:22701059

  20. Microbiological evaluation of chicken carcasses in an immersion chilling system with water renewal at 8 and 16 hours.

    Science.gov (United States)

    Souza, L C T; Pereira, J G; Spina, T L B; Izidoro, T B; Oliveira, A C; Pinto, J P A N

    2012-05-01

    Since 2004, Brazil has been the leading exporter of chicken. Because of the importance of this sector in the Brazilian economy, food safety must be ensured by control and monitoring of the production stages susceptible to contamination, such as the chilling process. The goal of this study was to evaluate changes in microbial levels on chicken carcasses and in chilling water after immersion in a chilling system for 8 and 16 h during commercial processing. An objective of the study was to encourage discussion regarding the Brazilian Ministry of Agriculture Livestock and Food Supply regulation that requires chicken processors to completely empty, clean, and disinfect each tank of the chilling system after every 8-h shift. Before and after immersion chilling, carcasses were collected and analyzed for mesophilic bacteria, Enterobacteriaceae, coliforms, and Escherichia coli. Samples of water from the chilling system were also analyzed for residual free chlorine. The results do not support required emptying of the chiller tank after 8 h; these tanks could be emptied after 16 h. The results for all carcasses tested at the 8- and 16-h time points indicated no significant differences in the microbiological indicators evaluated. These data provide both technical and scientific support for discussing changes in federal law regarding the management of immersion chilling water systems used as part of the poultry processing line.

  1. Determining the physiochemical changes and time of chilling injury incidence during cold storage of pomegranate fruit

    Directory of Open Access Journals (Sweden)

    Taghipour Leila

    2015-01-01

    Full Text Available Intermittent warming (IW is a good postharvest technique to prevent or alleviate chilling injuries during cold storage. Performing the warming treatment at the period of time before chilling injury is irreversible during storage, and it is the first prerequisite for a successful IW treatment. In order to determine the fruit physiochemical changes and time of irreversible chilling injury incidence during cold storage of pomegranate fruit (cv. Rabab-e-Neyriz, this research was conducted. Fruits were stored at 2 ± 0.5°C and 90 ± 5% relative humidity for 90 days. At 15-day intervals, 40 fruits (four replicates and 10 fruits in each replicate were sampled and further stored at 20°C for 3 days (shelf life. Chilling injury (CI index and weight loss (WL in intact fruits, electrolyte leakage (EL and K leakage (KL in peel samples, total soluble solids (TSS, titratable acidity (TA, TSS/TA ratio and pH in fruit juice were measured. With respect to quality parameters, TSS did not change significantly under cold storage. According to TA changes, the TSS/TA ratio was decreased up to 30 days but subsequently increased and the highest ratio was detected at the end of storage, which was significantly higher than the TSS/TA ratio at the harvest time. Results related to CI index, WL, EL and KL showed that pomegranate fruits could be stored cold without significant chilling damages up to 30 days. It was suggested that performing the IW treatment during this period could be concomitant with desired effects in long-term storage of this commercial cultivar.

  2. Nitric Oxide Mediates 5-Aminolevulinic Acid-Induced Antioxidant Defense in Leaves of Elymus nutans Griseb. Exposed to Chilling Stress.

    Directory of Open Access Journals (Sweden)

    Juanjuan Fu

    Full Text Available Nitric oxide (NO and 5-aminolevulinic acid (ALA are both extremely important signalling molecules employed by plants to control many aspects of physiology. In the present study, the role of NO in ALA-induced antioxidant defense in leaves of two sources of Elymus nutans Griseb. (Damxung, DX and Zhengdao, ZD was investigated. Chilling stress enhanced electrolyte leakage, accumulation of malondialdehyde (MDA, hydrogen peroxide (H2O2 and superoxide radical in two E. nutans, which were substantially alleviated by exogenous ALA and NO application. Pretreatment with NO scavenger PTIO or NOS inhibitor L-NNA alone and in combination with ALA induced enhancements in electrolyte leakage and the accumulation of MDA, H2O2 and superoxide radical in leaves of DX and ZD exposed to chilling stress, indicating that the inhibition of NO biosynthesis reduced the chilling resistance of E. nutans and the ALA-enhanced chilling resistance. Further analyses showed that ALA and NO enhanced antioxidant defense and activated plasma membrane (PM H+-ATPase and decreased the accumulation of ROS induced by chilling stress. A pronounced increase in nitric oxide synthase (NOS activity and NO release by exogenous ALA treatment was found in chilling-resistant DX plants exposed to chilling stress, while only a little increase was observed in chilling-sensitive ZD. Furthermore, inhibition of NO accumulation by PTIO or L-NNA blocked the protective effect of exogenous ALA, while both exogenous NO treatment and inhibition of endogenous NO accumulation did not induce ALA production. These results suggested that NO might be a downstream signal mediating ALA-induced chilling resistance in E. nutans.

  3. Structural basis for the activation mechanism of the PlcR virulence regulator by the quorum-sensing signal peptide PapR

    OpenAIRE

    Grenha, Rosa; Slamti, Leyla; Nicaise, Magali; Refes, Yacine; Lereclus, Didier; Nessler, Sylvie

    2012-01-01

    The quorum-sensing regulator PlcR is the master regulator of most known virulence factors in Bacillus cereus. It is a helix-turn-helix (HTH)-type transcription factor activated upon binding of its cognate signaling peptide PapR on a tetratricopeptide repeat-type regulatory domain. The structural and functional properties of PlcR have defined a new family of sensor regulators, called the RNPP family (for Rap, NprR, PrgX, and PlcR), in Gram-positive bacteria. To fully understand the activation ...

  4. Effect of pre-chilling and environmental factors on breaking seed dormancy and germination of three foxtail species

    OpenAIRE

    Vajihe AMINI; Faezeh ZAEFARIAN; Rezvani, Mohammad

    2015-01-01

    The effect of wet and dry pre-chilling duration, pH, osmotic stress, salt stress and planting depth on seed germination and seedling emergence of three foxtail species (Setaria glauca, S. verticillata and S. viridis) was investigated in a series of laboratory and greenhouse experiments. Both wet and dry pre-chilling for 45 days promoted seed germination of S. glauca compared with the control. Pre-chilling was not significantly effective in seed dormancy breaking of S. viridis and S. verticill...

  5. Study of a Two-Pipe Chilled Beam System for both Cooling and Heating of Office Buildings

    DEFF Research Database (Denmark)

    Gordnorouzi, Rouzbeh; Hultmark, Göran; Afshari, Alireza;

    Active chilled beam systems are used to provide heating and cooling in order to achieve comfortable thermal indoor climate. For heating and cooling applications, an active chilled beam has two water circuits comprising four pipes that supply warm and cold water respectively to the beam coil...... according to the space demand. Lindab Comfort A/S has introduced an active chilled beam system which has just one water circuit (two pipes) that is used for both heating and cooling. The concept is based on high temperature cooling and low temperature heating. In this study the energy saving potential...

  6. Remote Sensing.

    Science.gov (United States)

    Williams, Richard S., Jr.; Southworth, C. Scott

    1983-01-01

    The Landsat Program became the major event of 1982 in geological remote sensing with the successful launch of Landsat 4. Other 1982 remote sensing accomplishments, research, publications, (including a set of Landsat worldwide reference system index maps), and conferences are highlighted. (JN)

  7. 3D Reconstruction of geological structures based on remote sensing data: example from Anaran anticline, Lurestan province, Zagros folds and thrust belt, Iran.

    Science.gov (United States)

    Snidero, M.; Amilibia, A.; Gratacos, O.; Muñoz, J. A.

    2009-04-01

    This work presents a methodological workflow for the 3D reconstruction of geological surfaces at regional scale, based on remote sensing data and geological maps. This workflow has been tested on the reconstruction of the Anaran anticline, located in the Zagros Fold and Thrust belt mountain front. The used remote sensing data-set is a combination of Aster and Spot images as well as a high resolution digital elevation model. A consistent spatial positioning of the complete data-set in a 3D environment is necessary to obtain satisfactory results during the reconstruction. The Aster images have been processed by the Optimum Index Factor (OIF) technique, in order to facilitate the geological mapping. By pansharpening of the resulting Aster image with the SPOT panchromatic one we obtain the final high-resolution image used during the 3D mapping. Structural data (dip data) has been acquired through the analysis of the 3D mapped geological traces. Structural analysis of the resulting data-set allows us to divide the structure in different cylindrical domains. Related plunge lines orientation has been used to project data along the structure, covering areas with little or no information. Once a satisfactory dataset has been acquired, we reconstruct a selected horizon following the dip-domain concept. By manual editing, the obtained surfaces have been adjusted to the mapped geological limits as well as to the modeled faults. With the implementation of the Discrete Smooth Interpolation (DSI) algorithm, the final surfaces have been reconstructed along the anticline. Up to date the results demonstrate that the proposed methodology is a powerful tool for 3D reconstruction of geological surfaces when working with remote sensing data, in very inaccessible areas (eg. Iran, China, Africa). It is especially useful in semiarid regions where the structure strongly controls the topography. The reconstructed surfaces clearly show the geometry in the different sectors of the structure

  8. Structure/Function Analysis of the Pantoea stewartii Quorum-Sensing Regulator EsaR as an Activator of Transcription▿

    OpenAIRE

    Daniel J Schu; Carlier, Aurelien L; Jamison, Katherine P.; von Bodman, Susanne; Stevens, Ann M.

    2009-01-01

    In Pantoea stewartii subsp. stewartii, two regulatory proteins are key to the process of cell-cell communication known as quorum sensing: the LuxI and LuxR homologues EsaI and EsaR. Most LuxR homologues function as activators of transcription in the presence of their cognate acylated homoserine lactone (AHL) signal. However, EsaR was initially found to function as a repressor in the absence of AHL. Previous studies demonstrated that, in the absence of AHL, EsaR retains the ability to function...

  9. Physical and metabolic causes of sub-lethal damage in Listeria monocytogenes after long-term chilled storage at 4 degrees C.

    Science.gov (United States)

    Dykes, G A

    1999-12-01

    Cells of Listeria monocytogenes display sub-lethal injury when subjected to long-term chill-storage in a nutrient-poor environment. The physical and metabolic causes of sub-lethal injury to two meat (L61 and L62) and two clinical (L98 and L99) L. monocytogenes strains chill-stored (4 degrees C) for 4 weeks in phosphate-buffered saline at pH 7.0 and pH 5.5, and pH 5.5 in the presence of 0.3% potassium sorbate, were characterized. Causes of sub-lethal injury were determined by examining changes in the cell structure, leakage of nucleic acids and proteins from the cells, and cell recovery from injury in the presence of the metabolic inhibitors rifampicin, D-cycloserine, carbonyl cyanide m-chlorophenylhydrazone and chloramphenicol. Visible shrinkage of the cytoplasm and slight cell wall damage were apparent over the 4 week storage period by electron microscopy for all four strains and three storage conditions. By contrast, over the same storage period, only three of the strains (L62, L98 and L99) displayed slight leakage of cellular content in all three storage media, while one strain (L61) displayed greater leakage. The three strains also displayed similar storage media-dependent metabolic damage. For these strains, phosphate-buffered saline pH 5.5 caused the least damage and potassium sorbate, the most. Recovery experiments also indicated that at pH 5.5, the energy transduction system of these three strains remained undamaged, and that injury to the cell transcription machinery was greatest at pH 7.0. The fourth strain, L61, displayed less damage than the others but this was attributed to the death of the injured cell sub-population in this strain. In this study, damage to sub-lethally injured chill-stored L. monocytogenes was different from that caused by other agents, such as heat. Therefore, cells injured by chill-storage under starvation conditions may require novel protocols to assure their effective recovery.

  10. Structural, morphological, optical and gas sensing properties of pure and Ru doped SnO{sub 2} thin films by nebulizer spray pyrolysis technique

    Energy Technology Data Exchange (ETDEWEB)

    Sankar, C. [Department of Physics, Sri Ramakrishna Mission Vidyalaya College of Arts and Science, Coimbatore 641 020 (India); Ponnuswamy, V., E-mail: sankarphysics@gmail.com [Department of Physics, Sri Ramakrishna Mission Vidyalaya College of Arts and Science, Coimbatore 641 020 (India); Manickam, M. [Department of Physics, Sri Ramakrishna Mission Vidyalaya College of Arts and Science, Coimbatore 641 020 (India); Mariappan, R. [Department of Physics, Adhiyaman College of Engineering and Technology, Hosur 635 109 (India); Suresh, R. [Department of Physics, Sri Ramakrishna Mission Vidyalaya College of Arts and Science, Coimbatore 641 020 (India)

    2015-09-15

    Highlights: • Ruthenium doped tin oxide thin films at 450 °C by nebulizer spray pyrolysis technique. • Films characterized by XRD, SEM, EDS, UV–Vis and gas sensing properties. • Ethanol is good sensing gas compared with acetone, methanol, 2-methoxy ethanol and ammonia gases for pure and RTO thin films. - Abstract: Tin oxide thin films doped with different concentrations of ruthenium were deposited on the glass substrates at 450 °C by nebulizer spray pyrolysis technique. The structural, morphological, thickness and optical properties of thin films were investigated by X-ray diffraction, scanning electron microscopy, stylus profilometer and ultra violet spectrometer techniques. X-ray diffraction pattern confirms the tetragonal crystal structure for pure and ruthenium doped tin dioxide thin films. Ruthenium doped tin dioxide thin films are polycrystalline in nature. Scanning electron microscopy shows the modification of surface morphology of tin dioxide films due to varying concentration of ruthenium. Largest spheres, rings and interconnected fibers are present in the scanning electron microscopy images. Energy dispersive analysis reveals the average atomic percentage of pure and ruthenium doped tin dioxide present in the films developed. Stylus profilometer was used to measure the film thickness. Pure, 5, 10 and 15 wt% ruthenium doped tin dioxide thin films are found to have 327, 349, 386 and 425 nm thickness. Optical studies divulge that the band gap energy decreases from 3.55 eV to 3.04 eV due to the increased ruthenium concentrations. Gas sensing properties of pure and ruthenium doped tin dioxide thin films have been studied for various gases.

  11. Structural, morphological, optical and gas sensing properties of pure and Ru doped SnO2 thin films by nebulizer spray pyrolysis technique

    International Nuclear Information System (INIS)

    Highlights: • Ruthenium doped tin oxide thin films at 450 °C by nebulizer spray pyrolysis technique. • Films characterized by XRD, SEM, EDS, UV–Vis and gas sensing properties. • Ethanol is good sensing gas compared with acetone, methanol, 2-methoxy ethanol and ammonia gases for pure and RTO thin films. - Abstract: Tin oxide thin films doped with different concentrations of ruthenium were deposited on the glass substrates at 450 °C by nebulizer spray pyrolysis technique. The structural, morphological, thickness and optical properties of thin films were investigated by X-ray diffraction, scanning electron microscopy, stylus profilometer and ultra violet spectrometer techniques. X-ray diffraction pattern confirms the tetragonal crystal structure for pure and ruthenium doped tin dioxide thin films. Ruthenium doped tin dioxide thin films are polycrystalline in nature. Scanning electron microscopy shows the modification of surface morphology of tin dioxide films due to varying concentration of ruthenium. Largest spheres, rings and interconnected fibers are present in the scanning electron microscopy images. Energy dispersive analysis reveals the average atomic percentage of pure and ruthenium doped tin dioxide present in the films developed. Stylus profilometer was used to measure the film thickness. Pure, 5, 10 and 15 wt% ruthenium doped tin dioxide thin films are found to have 327, 349, 386 and 425 nm thickness. Optical studies divulge that the band gap energy decreases from 3.55 eV to 3.04 eV due to the increased ruthenium concentrations. Gas sensing properties of pure and ruthenium doped tin dioxide thin films have been studied for various gases

  12. Star in Deep Freeze Chills Theory, MIT Researchers Report

    Science.gov (United States)

    2001-09-01

    CAMBRIDGE, Mass. -- Like a frozen turkey that just won't thaw, a strange star near the center of the Milky Way is surprising MIT experts and colleagues with its remarkably low temperature. The odd behavior is chilling current theories of stellar physics. A famously battered neutron star named KS 1731-260 appears no hotter than some of its tranquil brethren, despite enduring the heat of constant thermonuclear explosions with the force of billions of hydrogen bombs every second across a region only a few miles wide for the past 12 years. Dr. Rudi Wijnands, an astrophysicist at MIT's Center for Space Research, used the Chandra X-ray Observatory to measure the temperature of the neutron star at a very opportune moment, only months after the nuclear war apparently ended and the smoke cleared. He presented his team's findings September 5 in Washington, D.C. at a scientific conference entitled "Two Years of Science with Chandra." "Twelve years of constant thermonuclear explosions: One would think that would heat things up," said Wijnands. "This leaves us wondering whether some neutron stars are in the freezer for a much longer time than previously thought and consequently take a long time to heat up, or whether they cool down incredibly fast. Either explanation has profound implications for our field." Neutron stars are the dense, core remains of stars once many times more massive than our Sun. They are created in dazzling supernovas, in which the outer shell of the star explodes into space, and the core, containing about as much mass as the Sun, implodes and collapses into a sphere no wider than Cambridge, Massachusetts. Despite their tiny size, neutron stars are visible in several ways. One is through accretion. Neutron stars are a strong source of gravity. When they exist in binary star systems, such as KS 1731-260, they can attract the gas from what is often a "healthy" hydrogen-burning companion star (although the nature of KS 1731-260's companion is not clear.) Gas

  13. Elements in nucleotide sensing and hydrolysis of the AAA+ disaggregation machine ClpB: a structure-based mechanistic dissection of a molecular motor

    Energy Technology Data Exchange (ETDEWEB)

    Zeymer, Cathleen, E-mail: cathleen.zeymer@mpimf-heidelberg.mpg.de; Barends, Thomas R. M.; Werbeck, Nicolas D.; Schlichting, Ilme; Reinstein, Jochen, E-mail: cathleen.zeymer@mpimf-heidelberg.mpg.de [Max Planck Institute for Medical Research, Jahnstrasse 29, 69120 Heidelberg (Germany)

    2014-02-01

    High-resolution crystal structures together with mutational analysis and transient kinetics experiments were utilized to understand nucleotide sensing and the regulation of the ATPase cycle in an AAA+ molecular motor. ATPases of the AAA+ superfamily are large oligomeric molecular machines that remodel their substrates by converting the energy from ATP hydrolysis into mechanical force. This study focuses on the molecular chaperone ClpB, the bacterial homologue of Hsp104, which reactivates aggregated proteins under cellular stress conditions. Based on high-resolution crystal structures in different nucleotide states, mutational analysis and nucleotide-binding kinetics experiments, the ATPase cycle of the C-terminal nucleotide-binding domain (NBD2), one of the motor subunits of this AAA+ disaggregation machine, is dissected mechanistically. The results provide insights into nucleotide sensing, explaining how the conserved sensor 2 motif contributes to the discrimination between ADP and ATP binding. Furthermore, the role of a conserved active-site arginine (Arg621), which controls binding of the essential Mg{sup 2+} ion, is described. Finally, a hypothesis is presented as to how the ATPase activity is regulated by a conformational switch that involves the essential Walker A lysine. In the proposed model, an unusual side-chain conformation of this highly conserved residue stabilizes a catalytically inactive state, thereby avoiding unnecessary ATP hydrolysis.

  14. Effect of variation of precursor concentration on structural, microstructural, optical and gas sensing properties of nanocrystalline TiO2 thin films prepared by spray pyrolysis techniques

    Indian Academy of Sciences (India)

    Lalchand A Patil; Dinesh N Suryawanshi; Idris G Pathan; Dhanashri G Patil

    2013-12-01

    The objective of the present paper is to investigate the effect of variation of precursor concentration (0.01, 0.02 and 0.03 M) on the structural, microstructural, optical and gas sensing properties of TiO2 thin films. Titanium dioxide (TiO2) films were prepared from aqueous solution of titanium chloride (TiCl3.6H2O, 99.9%pure, Merckmade, Germany) onto the glass substrates heated at a temperature of 350 °C by the spray pyrolysis technique. Bandgap energy of the films vary from 3.28 to 3.29 eV. X-ray diffraction shows that films to be nanocrystalline with anatase phase having tetragonal crystal structure. The values calculated from electron diffraction patterns (TEM) were observed to be matching with values calculated from XRD. Transmission electron microscopy (TEM) reveled that grain sizes were observed to increase (10–29 nm) with an increase in the concentration of precursor solution. The gas sensing performance of the films was tested.

  15. Remote sensing of local structure of the quasi-perpendicular Earth's bow shock by using field-aligned beams

    Directory of Open Access Journals (Sweden)

    B. Miao

    2009-03-01

    Full Text Available Field-aligned ion beams (FABs originate at the quasi-perpendicular Earth's bow shock and constitute an important ion population in the foreshock region. The bulk velocity of these FABs depends significantly on the shock normal angle, which is the angle between shock normal and upstream interplanetary magnetic field (IMF. This dependency may therefore be taken as an indicator of the local structure of the shock. Applying the direct reflection model to Cluster measurements, we have developed a method that uses proton FABs in the foreshock region for remote sensing of the local shock structure. The comparison of the model results with the multi-spacecraft observations of FAB events shows very good agreement in terms of wave amplitude and frequency of surface waves at the shock front.

  16. Comparison of residual stresses in sand- and chill casting of ductile cast iron wind turbine main shafts

    DEFF Research Database (Denmark)

    Sonne, Mads Rostgaard; Frandsen, J. O.; Hattel, Jesper Henri

    2015-01-01

    In this work, simulations of pouring, solidification and cooling, and residual stress evolution of sand and chill cast wind turbine main shafts is performed. The models are made in the commercial software MAGMAsoft. As expected, the cooling rate of the sand casting is shown to be much lower than...... for the chill casting, resulting in a very course microstructure.From the simulations the nodule count is found to be 17 nodules per mm2 and 159 nodules permm2 for the sand and chill casting, respectively, in the critical region of the main bearing seat.This is verified from nodule counts performed on...... the real cast main shafts. Residual stressevaluations show an overall increase of the maximum principal stress field for the chill casting,which is expected. However, the stresses are found to be in compression on the surface of thechill cast main shaft, which is unforeseen....

  17. Performance of personalized ventilation combined with chilled ceiling in an office room: inhaled air quality and contaminant distribution

    DEFF Research Database (Denmark)

    Lipczynska, Aleksandra; Kaczmarczyk, Jan; Melikov, Arsen Krikor

    2014-01-01

    In a simulated two persons’ office room inhaled air quality and contaminant distribution provided with personalized ventilation combined with chilled ceiling, mixing ventilation only, chilled ceiling with mixing ventilation and chilled ceiling with mixing and personalized ventilation was studied...... people (exhaled air, bioeffluents) and building materials (wall painting). Personalized ventilation combined with chilled ceiling ensured highest air quality at the workstation under all conditions. Pollutant concentration in the occupied zone away from the workstations did not differ substantially....... Breathing thermal manikins were used to resemble two occupants at workstations. Room air temperature was kept at 26ºC and 28°C. Personalized ventilation supplied air at 25°C. Supplied total flow rate ranged from 26 to 82 L/s. Heat gains of 66-72 W/m2 were simulated. Tracer gases simulated pollution from...

  18. Redox Signaling and CBF-Responsive Pathway Are Involved in Salicylic Acid-Improved Photosynthesis and Growth under Chilling Stress in Watermelon

    Science.gov (United States)

    Cheng, Fei; Lu, Junyang; Gao, Min; Shi, Kai; Kong, Qiusheng; Huang, Yuan; Bie, Zhilong

    2016-01-01

    Salicylic acid (SA) plays an important role in plant response to abiotic stresses. This study investigated the potential role of SA in alleviating the adverse effects of chilling stress on photosynthesis and growth in watermelon (Citrullus lanatus). Chilling stress induced the simultaneous accumulation of free and conjugated SA in watermelon plants, and the chilling-induced SA production was attributed to the phenylalanine ammonia-lyase pathway. Applying SA at moderate concentrations induced chilling tolerance, whereas inhibition of SA biosynthesis by L-α-aminooxy-β-phenylpropionic acid (AOPP) increased the photooxidation of PS II under chilling stress in watermelon, resulting in reduced photosynthesis and growth. Chilling induced a transient increase in the ratios of reduced to oxidized glutathione and reduced ascorbate to dehydroascorbate. Then, the expression of antioxidant genes was upregulated, and the activities of antioxidant enzymes were enhanced. Furthermore, SA-induced chilling tolerance was associated with cellular glutathione and ascorbate homeostasis, which served as redox signals to regulate antioxidant metabolism under chilling stress. AOPP treatment stimulated the chilling-induced expression of cold-responsive genes, particularly via C-repeat binding factors CBF3 and CBF4. These results confirm the synergistic role of SA signaling and the CBF-dependent responsive pathway during chilling stress in watermelon. PMID:27777580

  19. Teachers' sense-making of curriculum structures and its impact on the implementation of an innovative reform-based science curriculum

    Science.gov (United States)

    Beckford-Smart, Meredith

    This study discusses the social interactions involved in teachers' enactment and use of new science curricula. The teachers studied participated in the LiFE program, a university-school partnership, which is an inquiry based science and nutrition education program. In this program fifth and sixth grade students learned science through the study of food. The program used the study of food and food systems to teach life sciences and nutrition through inquiry based studies. Through the partnership teachers received professional development which aimed to deepen their conceptual understandings of life science and develop skills in implementing inquiry-base teaching. Using qualitative research methods of ethnography and narrative inquiry to study teachers' sense-making of messages from curriculum structures, the intention was to explore how teachers' sense-making of these structures guided their classroom practices. Two research questions were addressed: (a) How do teachers make sense of curriculum given their perceptions, their school context and their curricular context; (b) What influence do their identities as science teachers/learners have on their enactment of an innovative science curriculum. I used comparative analysis to examine teacher's beliefs and identities as teachers/learners. In the process of studying these teachers an understanding of how teachers' stories and identities shape their use and enactment of science curriculum came to light. The initial analysis revealed four distinct teacher identities: (a) social responsibility teacher/learner; (b) experiential teacher/learner; (c) supportive institution teacher/learner; and (d) turning point teacher. Besides these distinct teacher identities three cross cutting themes emerged: (a) creating environments conducive to their teaching visions; (b) empowering student through science teaching; and (c) dealing with the uncertainty of teaching. The information gathered from this study will illuminate how these

  20. Variation in chilling tolerance for photosynthesis and leaf extension growth among genotypes related to the C-4 grass Miscanthus xgiganteus

    Energy Technology Data Exchange (ETDEWEB)

    Glowacka, K; Adhikari, S; Peng, JH; Gifford, J; Juvik, JA; Long, SP; Sacks, EJ

    2014-09-08

    The goal of this study was to identify cold-tolerant genotypes within two species of Miscanthus related to the exceptionally chilling-tolerant C-4 biomass crop accession: M. xgiganteus 'Illinois' (Mxg) as well as in other Mxg genotypes. The ratio of leaf elongation at 10 degrees C/5 degrees C to that at 25 degrees C/25 degrees C was used to identify initially the 13 most promising Miscanthus genotypes out of 51 studied. Net leaf CO2 uptake (A(sat)) and the maximum operating efficiency of photosystem II (Phi(PSII)) were measured in warm conditions (25 degrees C/20 degrees C), and then during and following a chilling treatment of 10 degrees C/5 degrees C for 11 d. Accessions of M. sacchariflorus (Msa) showed the smallest decline in leaf elongation on transfer to chilling conditions and did not differ significantly from Mxg, indicating greater chilling tolerance than diploid M. sinensis (Msi). Msa also showed the smallest reductions in A(sat) and Phi(PSII), and greater chilling-tolerant photosynthesis than Msi, and three other forms of Mxg, including new triploid accessions and a hexaploid Mxg 'Illinois'. Tetraploid Msa 'PF30153' collected in Gifu Prefecture in Honshu, Japan did not differ significantly from Mxg 'Illinois' in leaf elongation and photosynthesis at low temperature, but was significantly superior to all other forms of Mxg tested. The results suggested that the exceptional chilling tolerance of Mxg 'Illinois' cannot be explained simply by the hybrid vigour of this intraspecific allotriploid. Selection of chilling-tolerant accessions from both of Mxg's parental species, Msi and Msa, would be advisable for breeding new highly chilling-tolerant Mxg genotypes.

  1. Artificial selection on chill-coma recovery time in Drosophila melanogaster: Direct and correlated responses to selection.

    Science.gov (United States)

    Gerken, Alison R; Mackay, Trudy F C; Morgan, Theodore J

    2016-07-01

    Artificial selection can be used to create populations with extreme phenotypic responses to environmental stressors. When artificial selection is applied to a single component of a stress response, this selection may result in correlated responses in other stress responses, a phenomenon called cross-tolerance, which is ultimately controlled by the genetic correlations among traits. We selected for extreme responses to cold tolerance by selecting for chill-coma recovery time from a single temperate population of Drosophila melanogaster. Chill-coma recovery time is a common metric of low, but non-lethal, cold temperature tolerance. Replicated divergent artificial selection was applied to a genetically variable base population for 31 generations, resulting in two cold resistant, two cold susceptible, and two unselected control lines. To quantify the relationship between selection on chill-coma recovery and other metrics of thermal performance, we also measured survivorship after acute cold exposure, survivorship after chronic cold exposure, survivorship after cold exposure following a pre-treatment period (rapid cold hardening), starvation tolerance, and heat tolerance. We find that chill-coma recovery time is heritable within this population and that there is an asymmetric response to increased and decreased chill-coma recovery time. Surprisingly, we found no cross-tolerances between selection on chill-coma recovery time and the other environmental stress response traits. These results suggest that although artificial selection has dramatically altered chill-coma recovery time, the correlated response to selection on other stress response phenotypes has been negligible. The lack of a correlated response suggests that chill-coma recovery time in these selection lines is likely genetically independent from measures of cold survivorship tested here.

  2. CFX Analysis of the Heat and Mass Transfer During the Chilling of a Lamb Carcass using a 3D Model

    OpenAIRE

    Hannon, Joseph; Keane, Garrett; O'Flaherty, Micheal

    2013-01-01

    Lamb meat is a popular red meat which must go through a complex refrigeration process before being served at the dinner table to reduce bacterial growth and retain meat quality. A major disadvantage of chilling is the drip losses which are losses in weight by evaporation of water contained within the meat. The aim of this work is to simulate the conventional chilling process of a lamb carcass using a three dimensional model.

  3. Comparative metabolomic analysis reveals a reactive oxygen species-dominated dynamic model underlying chilling environment adaptation and tolerance in rice.

    Science.gov (United States)

    Zhang, Jingyu; Luo, Wei; Zhao, Yuan; Xu, Yunyuan; Song, Shuhui; Chong, Kang

    2016-09-01

    Cold, a major environmental stress for plants, has been studied intensively for decades. Its response system has been revealed, especially at the transcriptional level. The mechanisms underlying recovery growth and environmental adaptation, however, remain unknown. Taking advantage of a naturally existing system, two subspecies of Asian cultivated rice (Oryza sativa) with significant divergence in chilling tolerance, we analyzed representative japonica and indica varieties, Nipponbare and 93-11, using comparative metabolomic analysis at six time points covering chilling treatment and recovery. In total, 223 known metabolites were detected. During chilling treatment, significant biochemical changes were centered on antioxidation. During recovery, a wide-ranging chilling response was observed. Large-scale amino acid accumulation occurred, consistent with the appearance of chilling injury. At the mid-treatment stage, the accumulation of antioxidation-related compounds appeared earlier in Nipponbare than in 93-11, consistent with the higher reactive oxygen species (ROS) levels in japonica vs indica varieties. A significant contribution of ROS-mediated gene regulation, rather than the C-repeat binding factor/dehydration-responsive-element binding factor (CBF/DREB) regulon, to the more vigorous transcriptional stress response in Nipponbare was revealed by RNA-seq. Accordingly, during recovery, the induction of stress-tolerant-related metabolites was more active in the chilling-tolerant variety Nipponbare. Senescence-related compounds accumulated only in the chilling-sensitive variety 93-11. Our study uncovers the dynamic metabolic models underlying chilling response and recovery, and reveals a ROS-dominated rice adaptation mechanism to low-temperature environments. PMID:27198693

  4. “On-Off” Thermoresponsive Coating Agent Containing Salicylic Acid Applied to Maize Seeds for Chilling Tolerance

    OpenAIRE

    Guan, Yajing; Li, Zhan; He, Fei; Huang, Yutao; Song, Wenjian; Hu, Jin

    2015-01-01

    Chilling stress is an important constraint for maize seed establishment in the field. In this study, a type of “on-off” thermoresponsive coating agent containing poly (N-isopropylacrylamide-co-butylmethacrylate) (Abbr. P(NIPAm-co-BMA)) hydrogel was developed to improve the chilling tolerance of coated maize seed. The P(NIPAm-co-BMA) hydrogel was synthesized by free-radical polymerization of N-isopropylacrylamide (NIPAm) and butylmethacrylate (BMA). Salicylic acid (SA) was loaded in the hydrog...

  5. Artificial selection on chill-coma recovery time in Drosophila melanogaster: Direct and correlated responses to selection.

    Science.gov (United States)

    Gerken, Alison R; Mackay, Trudy F C; Morgan, Theodore J

    2016-07-01

    Artificial selection can be used to create populations with extreme phenotypic responses to environmental stressors. When artificial selection is applied to a single component of a stress response, this selection may result in correlated responses in other stress responses, a phenomenon called cross-tolerance, which is ultimately controlled by the genetic correlations among traits. We selected for extreme responses to cold tolerance by selecting for chill-coma recovery time from a single temperate population of Drosophila melanogaster. Chill-coma recovery time is a common metric of low, but non-lethal, cold temperature tolerance. Replicated divergent artificial selection was applied to a genetically variable base population for 31 generations, resulting in two cold resistant, two cold susceptible, and two unselected control lines. To quantify the relationship between selection on chill-coma recovery and other metrics of thermal performance, we also measured survivorship after acute cold exposure, survivorship after chronic cold exposure, survivorship after cold exposure following a pre-treatment period (rapid cold hardening), starvation tolerance, and heat tolerance. We find that chill-coma recovery time is heritable within this population and that there is an asymmetric response to increased and decreased chill-coma recovery time. Surprisingly, we found no cross-tolerances between selection on chill-coma recovery time and the other environmental stress response traits. These results suggest that although artificial selection has dramatically altered chill-coma recovery time, the correlated response to selection on other stress response phenotypes has been negligible. The lack of a correlated response suggests that chill-coma recovery time in these selection lines is likely genetically independent from measures of cold survivorship tested here. PMID:27264892

  6. Influence of heat treatment on the microstructure and wear behavior of end-chill cast Zn-27Al alloys with different copper content

    Science.gov (United States)

    Jeshvaghani, R. Arabi; Ghahvechian, H.; Pirnajmeddin, H.; Shahverdi, H. R.

    2016-04-01

    The aim of this paper was to study the effect of heat treatment on the microstructure and wear behavior of Zn-27Al alloys with different copper content. In order to study the relationship between microstructure features and wear behavior, the alloys prepared by an end-chill cast apparatus and then heat treated. Heat treatment procedure involved solutionizing at temperature of 350 °C for 72 h followed by cooling within the furnace to room temperature. Microstructural characteristics of as-cast and heat-treated alloys at different distances from the chill were investigated by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction. Wear tests were performed using a pin-on-disk test machine. To determine the wear mechanisms, the worn surfaces of the samples were also examined by SEM and EDS. Results showed that heat treatment led to the complete dissolution of as-cast dendritic microstructure and formation of a fine lamellar structure with well-distributed microconstituents. Moreover, addition of copper up to 1 wt% had no significant change in the microstructure, while addition of 2 and 4 wt% copper resulted in formation of ɛ (CuZn4) particle in the interdendritic regions. The influence of copper content on the wear behavior of the alloys was explained in terms of microstructural characteristics. Delamination was proposed as the dominant wear mechanism.

  7. Cold Stress Tolerance in Psychrotolerant Soil Bacteria and Their Conferred Chilling Resistance in Tomato (Solanum lycopersicum Mill.) under Low Temperatures.

    Science.gov (United States)

    Subramanian, Parthiban; Kim, Kiyoon; Krishnamoorthy, Ramasamy; Mageswari, Anbazhagan; Selvakumar, Gopal; Sa, Tongmin

    2016-01-01

    The present work aimed to study the culturable diversity of psychrotolerant bacteria persistent in soil under overwintering conditions, evaluate their ability to sustain plant growth and alleviate chilling stress in tomato. Psychrotolerant bacteria were isolated from agricultural field soil samples colleced during winter and then used to study chilling stress alleviation in tomato plants (Solanum lycopersicum cv Mill). Selective isolation after enrichment at 5°C yielded 40 bacterial isolates. Phylogenetic studies indicated their distribution in genera Arthrobacter, Flavimonas, Flavobacterium, Massilia, Pedobacter and Pseudomonas. Strains OS211, OB146, OB155 and OS261 consistently improved germination and plant growth when a chilling stress of 15°C was imposed and therefore were selected for pot experiments. Tomato plants treated with the selected four isolates exhibited significant tolerance to chilling as observed through reduction in membrane damage and activation of antioxidant enzymes along with proline synthesis in the leaves when exposed to chilling temperature conditions (15°C). Psychrotolerant physiology of the isolated bacteria combined with their ability to improve germination, plant growth and induce antioxidant capacity in tomato plants can be employed to protect plants against chilling stress. PMID:27580055

  8. Exogenous Melatonin Treatment Increases Chilling Tolerance and Induces Defense Response in Harvested Peach Fruit during Cold Storage.

    Science.gov (United States)

    Cao, Shifeng; Song, Chunbo; Shao, Jiarong; Bian, Kun; Chen, Wei; Yang, Zhenfeng

    2016-06-29

    The effect of exogenous melatonin on chilling injury in peach fruit after harvest was investigated. To explore the optimum concentration of melatonin for chilling tolerance induction, peach fruit were treated with 50, 100, or 200 μM melatonin for 120 min and then stored for 28 days at 4 °C. The results showed that application of melatonin at 100 μM was most effective in reducing chilling injury of peach fruit after harvest. Peaches treated with melatonin at this concentration displayed higher levels of extractable juice rate and total soluble solids than the non-treated peaches. In addition, melatonin treatment enhanced expression of PpADC, PpODC, and PpGAD and consequently increased polyamines and γ-aminobutyric acid (GABA) contents. Meanwhile, the upregulated transcripts of PpADC and PpODC and inhibited PpPDH expression resulted in the higher proline content in melatonin-treated fruit compared to the control fruit. Our results revealed that melatonin treatment may be a useful technique to alleviate chilling injury in cold-stored peach fruit. The chilling tolerance of harvested peaches induced by melatonin treatment is associated with higher levels of polyamine, GABA, and proline. These data provided here are the first protective evidence of exogenous melatonin in harvested horticultural products in response to direct chilling stress. PMID:27281292

  9. Inhibition Effect of Herbal Preservatives on Listeria monocytogenes on Chilled Pork

    Institute of Scientific and Technical Information of China (English)

    LIU Liu; KONG Baohua; DIAO Xinping; LIU Jing

    2008-01-01

    This study investigated the growth situation of Listeria monocytogenes on chilled pork and the effect of herbal preservatives on this pathogen.The inhibitions of herbal preservatives were identified. The minimum inhibitory concentrations (MIC) of cinnamon and clove were all 0.79 mg·mL-1,while the rosemary was 1.58 mg.mL-1.And the composite herbal preservatives were got through orthogonal experiment.The optimum proportion was as following on agar medium:1.16 mg·mL-1 cinnamon+2.38 mg·mL-1 rosemary+3.17mg·mL-1 clove (herb combination number 5),while on chilled pork,the strong inhibition of L.monocytogenes was showed,which demonstrated that the surface application of herb combination resulted in an effective delay of L.monocytogenes growth.

  10. Use of gamma irradiation for improving the hygienic quality of chilled chicken

    International Nuclear Information System (INIS)

    Fresh, chilled chicken carcasses were irradiated at 2.5 kGy and stored at 40 degree C. At intervals samples were withdrawn for microbial, chemical and sensory evaluation. Result showed that combination of a 2.5 kGy irradiation dose and storage at 4 degree C were adequate for a radicidised chicken process. Immediately after irradiation, the microbial spoilage was reduced by at least 4 log cycles. The carcasses were qf excellent quality for at least 16 days of storage and were free from Salmonella and other food pathogens. Changes in chemical composition (moisture, fat, protein, ash and amino acids) and sensory quality of chicken carcasses irradiated at 2.5 kGy were not significant. Therefore the dose of 2.5 kGy should be the target for chilled chicken irradiation process

  11. Combining active chilled beams and air cleaning technologies to improve indoor climate in offices

    DEFF Research Database (Denmark)

    Ardkapan, Siamak Rahimi; Afshari, Alireza; Bergsøe, Niels Christian;

    2012-01-01

    in offices. For this purpose, a mechanical filter with low pressure drop was selected to be tested in a laboratory environment. The measurements included tests of the filter in a ductwork to study the efficiency of the filter. Moreover, the combined system of the filter and a chilled beam was tested...... in a room. The removal efficiency of the mechanical filter for ultrafine particles was examined using burning candles as sources for emission of particles. The measurements in the duct showed that the efficiency of the filter ranged between 54% and 78% and the pressure loss was less than 5 Pascal....... Furthermore, the measurement results of the combined system showed that adding the filter accelerated the removal rate of the particles by 2 (h-1). However, the efficiency of the chilled beam in exchanging the heat reduced by 38%....

  12. Combining active chilled beams and air-cleaning technologies to improve the indoor climate in offices

    DEFF Research Database (Denmark)

    Ardkapan, Siamak Rahimi; Afshari, Alireza; Bergsøe, Niels Christian;

    2013-01-01

    of air in offices. For this purpose, a mechanical filter with low pressure drop was selected for testing in a laboratory environment. The measurements included tests of the filter in a ductwork to study the efficiency of the filter. Moreover, the combined system of the filter and a chilled beam...... was tested in a room. The efficiency of the mechanical filter to remove ultrafine particles was examined using pure wax candles and salt as sources of emission of particles. The measurements in the duct showed that the efficiency of the filter ranged between 54% and 78% and that the pressure loss was less...... than 5 Pa (0.104 Ibf /ft2). Furthermore, the measurement results of the combined system showed that adding the filter accelerated the removal rate of the particles by 2 h-1. However, the efficiency of the chilled beam in exchanging heat was reduced by 38%....

  13. Calculation of the Chilling Requirement for Air Conditioning in the Excavation Roadway

    Directory of Open Access Journals (Sweden)

    Yueping Qin

    2015-10-01

    Full Text Available To effectively improve the climate conditions of the excavation roadway in coal mine, the calculation of the chilling requirement taking air conditioning measures is extremely necessary. The temperature field of the surrounding rock with moving boundary in the excavation roadway was numerically simulated by using finite volume method. The unstable heat transfer coefficient between the surrounding rock and air flow was obtained via the previous calculation. According to the coupling effects of the air flow inside and outside air duct, the differential calculation mathematical model of air flow temperature in the excavation roadway was established. The chilling requirement was calculated with the selfdeveloped computer program for forecasting the required cooling capacity of the excavation roadway. A good air conditioning effect had been observed after applying the calculated results to field trial, which indicated that the prediction method and calculation procedure were reliable.

  14. Potential energy savings with personalized ventilation coupled with passive chilled beams

    DEFF Research Database (Denmark)

    Lyubenova, Velina S.; Holsøe, Jan W.; Melikov, Arsen Krikor

    2011-01-01

    distribution used today. The potential of PV for energy saving has been studied little. In this study, the energy saving potential of desk mounted PV in conjunction with either mixing ventilation or a passive chilled beam system is compared to mixing ventilation alone by means of computer simulations. An open...... 20% (and up to 40% when extending the temperature in the room by 2 °C above the upper limit recommended in the standards) compared to mixing ventilation only. When PV was combined with passive chilled beams, the reduction of the supplied air was up to 80%. This ventiltion strategy may lead to energy......Personalized ventilation (PV) is an individually controlled air distribution system aimed at improving inhaled air quality and thermal comfort of each occupant. Numerous studies have shown that PV may improve occupants’ health, comfort and performance in comparison with traditional total volume air...

  15. Resting physiological arousal is associated with the experience of music-induced chills.

    Science.gov (United States)

    Mori, Kazuma; Iwanaga, Makoto

    2014-08-01

    In the study of emotion and autonomic nervous system functioning, resting physiological arousal is usually considered a negative characteristic. The present study examined the relationship between resting physiological arousal and positive emotional experience linked to psychophysiological arousal. We assessed resting physiological arousal using markers as high skin conductance level and low respiratory sinus arrhythmia, measured just before participants listened to their favorite music. Participants reported the sensation of chills (goose bumps, shivers) by pressing a mouse button while listening. The results indicated that individuals with resting physiological arousal frequently experience music-induced chills, which evoked unambiguous pleasurable feelings and an increase in skin conductance response. The current results, and the previously demonstrated relationship between resting physiological arousal and negative emotionality linked to psychophysiological arousal (e.g., anxiety, panic), suggest that resting physiological arousal may reflect sensitivity to psychophysiological arousal with both intense positive and negative emotions.

  16. Innovative two-pipe active chilled beam system for simultaneous heating and cooling of office buildings

    DEFF Research Database (Denmark)

    Maccarini, Alessandro; Afshari, Alireza; Bergsøe, Niels Christian;

    2014-01-01

    energy between zones with one hydronic circuit, operating with a water temperature between 20°C and 23°C. To calculate the energy performance of the system, simulation-based research was developed. The two-pipe system was modelled by using EnergyPlus, a whole building energy simulation program. Hourly......The aim of this paper was to investigate the energy savings potential of an innovative two-pipe system in an active chilled beam application for heating and cooling of office buildings. The characteristic of the system is its ability to provide simultaneous heating and cooling by transferring...... heating, cooling and ventilation loads were calculated by the program and an annual energy consumption evaluation of the system was made. Simulation results showed that the innovative two-pipe active chilled beam system used approximately 5% less energy than a conventional four-pipe system....

  17. Evaluating the ChillFish Biofeedback Game with Children with ADHD

    DEFF Research Database (Denmark)

    Sonne, Tobias; Jensen, Mads Møller

    Breathing exercises have been shown to have multiple benefits for children with Attention Deficit Hyperactivity Disorder (ADHD). However, these children can have issues retaining attention to such an exercise. In this paper we present a study of ChillFish, a respiration game for children with ADHD....... Our findings show tendencies that the game works in terms of having a calming effect. However, the study also highlighted issues of evaluating biofeedback games with children with ADHD that are not present when evaluating with adults. This work presents an iteration in the ChillFish development cycle...... that will hopefully result in a stable system that can assist children with ADHD in their everyday life....

  18. Survival of Listeria monocytogenes, Listeria innocua, and Lactic acid bacteria species in chill brine

    OpenAIRE

    Meadows, Bridget Archibald

    2004-01-01

    SURVIVAL OF LISTERIA MONOCYTOGENES, LISTERIA INNOCUA, AND LACTIC ACID BACTERIA SPECIES IN CHILL BRINES Bridget Archibald Meadows (ABSTRACT) Listeria monocytogenes is the major pathogen in ready-to-eat meat products such as deli meats and frankfurters. Contamination can occur via the salt brines that are used to cool thermally processed meats. Both L. monocytogenes and lactic acid bacteria can grow and thrive under these brine conditions, and may become competitive with each ot...

  19. Thrills, Chills, Frissons, and Skin Orgasms: Toward an Integrative Model of Transcendent Psychophysiological Moments in Music

    OpenAIRE

    Lucas D. Harrison; Psyche eLoui

    2014-01-01

    Music has a unique power to elicit moments of intense emotional and psychophysiological response. These moments – termed chills, thrills, frissons, etc. – are subjects of introspection and philosophical debate, as well as scientific study in music perception and cognition. The present article integrates the existing multidisciplinary literature in an attempt to define a comprehensive, testable, and ecologically valid model of transcendent psychophysiological moments in music.

  20. Thrills, chills, frissons, and skin orgasms: toward an integrative model of transcendent psychophysiological experiences in music

    OpenAIRE

    Harrison, Luke; Loui, Psyche

    2014-01-01

    Music has a unique power to elicit moments of intense emotional and psychophysiological response. These moments – termed “chills,” “thrills”, “frissons,” etc. – are subjects of introspection and philosophical debate, as well as scientific study in music perception and cognition. The present article integrates the existing multidisciplinary literature in an attempt to define a comprehensive, testable, and ecologically valid model of transcendent psychophysiological moments in music....

  1. Music Chills: The Eye Pupil as a Window to the Soul of Music

    OpenAIRE

    Eidet, Lise Mette

    2015-01-01

    Strong emotional and bodily experiences with music are a very complex phenomenon that may be best observed in terms of the involuntary bodily reactions that can accompany strong musical experiences. Based on the relationship between the activation of noradrenaline (NE) and changes in pupil size, there is a theoretical ground for studying pupillary reactions when experiencing music chills. In the present study, participants listened to self-chosen songs versus control songs chosen by the other...

  2. Sensory quality control in the chilled and frozen ready meal, soup and sauce sectors

    OpenAIRE

    Swainson, Mark; McWatt, Linda

    2010-01-01

    This chapter discusses the use of sensory evaluation in the assurance of product quality within the food production sectors of ready meals, soups and sauces. The chapter methodically reviews typical food processing stages, from recipe development through to end product supply, and considers how sensory assessment methods can be utilised to help assure the quality of the end products within these selected High Risk Chilled Food sectors.

  3. Successful artificial insemination in the Asian elephant (Elephas maximus using chilled and frozen-thawed semen

    Directory of Open Access Journals (Sweden)

    Wongkalasin Warut

    2009-07-01

    Full Text Available Abstract Background Artificial insemination (AI using frozen-thawed semen is well established and routinely used for breeding in various mammalian species. However, there is no report of the birth of elephant calves following AI with frozen-thawed semen. The objective of the present study was to investigate the fertilizing ability of chilled and frozen-thawed semen in the Asian elephant following artificial insemination (AI. Methods Semen samples were collected by from 8 bulls (age range, 12-to 42-years by manual stimulation. Semen with high quality were either cooled to 4°C or frozen in liquid nitrogen (-196°C before being used for AI. Blood samples collected from ten elephant females (age range, 12-to 52-years were assessed for estrus cycle and elephants with normal cycling were used for AI. Artificial insemination series were conducted during 2003 to 2008; 55 and 2 AI trials were conducted using frozen-thawed and chilled semen, respectively. Pregnancy was detected using transrectal ultrasonography and serum progestagen measurement. Results One female (Khod inseminated with chilled semen became pregnant and gave birth in 2007. The gestation length was 663 days and the sex of the elephant calf was male. One female (Sao inseminated with frozen-thawed semen showed signs of pregnancy by increasing progestagen levels and a fetus was observed for 5 months by transrectal ultrasonography. Conclusion This is the first report showing pregnancy following AI with frozen-thawed semen in the Asian elephant. Successful AI in the Asian elephant using either chilled or frozen-thawed semen is a stepping stone towards applying this technology for genetic improvement of the elephant population.

  4. Thrills, Chills, Frissons, and Skin Orgasms: Toward an Integrative Model of Transcendent Psychophysiological Moments in Music

    Directory of Open Access Journals (Sweden)

    Lucas D. Harrison

    2014-07-01

    Full Text Available Music has a unique power to elicit moments of intense emotional and psychophysiological response. These moments – termed chills, thrills, frissons, etc. – are subjects of introspection and philosophical debate, as well as scientific study in music perception and cognition. The present article integrates the existing multidisciplinary literature in an attempt to define a comprehensive, testable, and ecologically valid model of transcendent psychophysiological moments in music.

  5. Alternative Layouts for the Carbon Capture with the Chilled Ammonia Process

    OpenAIRE

    Valenti, Gianluca; Bonalumi, Davide; Fosbøl, Philip Loldrup; Macchi, Ennio; Thomsen, Kaj; Gatti, Dominicc

    2013-01-01

    Many alternatives are being investigated for the carbon capture, but none appears to have been proved as the choice for full-scale applications. This work considers the Chilled Ammonia Process for coal-fired Ultra Super Critical power plants. Three layouts are simulated with Aspen Plus and the Extended UNIQUAC thermodynamic model. Compared to a traditional layout, stripping of the wash water of the absorber or, better, splitting the rich solution between the middle and the top of the column l...

  6. Combined Treatments Reduce Chilling Injury and Maintain Fruit Quality in Avocado Fruit during Cold Quarantine

    OpenAIRE

    Sivankalyani, Velu; Feygenberg, Oleg; Maorer, Dalia; Zaaroor, Merav; Fallik, Elazar; Alkan, Noam

    2015-01-01

    Quarantine treatment enables export of avocado fruit (Persea americana) to parts of the world that enforce quarantine against fruit fly. The recommended cold-based quarantine treatment (storage at 1.1°C for 14 days) was studied with two commercial avocado cultivars ‘Hass’ and ‘Ettinger’ for 2 years. Chilling injuries (CIs) are prevalent in the avocado fruit after cold-quarantine treatment. Hence, we examined the effect of integrating several treatments: modified atmosphere (MA; fruit covered ...

  7. Spatial Structuring and the Development of Number Sense: A Case Study of Young Children Working with Blocks

    Science.gov (United States)

    van Nes, Fenna; van Eerde, Dolly

    2010-01-01

    This case study discusses an activity that makes up one of five lessons in an ongoing classroom teaching experiment. The goal of the teaching experiment is (a) to gain insight into kindergartners' spatial structuring abilities, and (b) to design an educational setting that can support kindergartners in becoming aware of spatial structures and in…

  8. Research progress in chilling injury of banana and its cultivation techniques against chilling%香蕉寒害及防寒栽培技术研究进展

    Institute of Scientific and Technical Information of China (English)

    牟海飞; 吴代东; 邹瑜; 林贵美; 张进忠

    2012-01-01

    Banana, sensitive to temperature, is vulnerable to chilling. Accordingly chilling resistance research, chilling forecast and prevention of banana is a long-standing critical challenge of banana production in China. Definition, symptoms and physiology of chilling injury together with meteorology and chilling-resistant cultivation measures were re-viewed based on relevant literaiure in recent 30 years. Key issues in this regard were described as follows: The first, critical concepts concerning banana chilling injury were mixed-up; the second, allogenic. materials could not he used to improve chilling resistance capability in practical production; the third, banana production was mainly distributed in less-suitable planting areas; the fourth, unbalance existed in banana demand and supply after cold injury; and the last, lack of cold-resistant banana cullivars. A series of corresponding countemeasures were put forward in order to provide references for chilling injury research, chilling resistance cultivation , post-disaster production recovery and chilling resistant varieties breeding.%香蕉对温度极为敏感,抗寒性差,香蕉抗寒的研究和预测防御是我国香蕉生产长期存在的关键性难题.文章参考近30年的有关文献,对香蕉的寒害定义、寒害症状、寒害生理学、气象学、防寒栽培措施等进行综述,指出我国香蕉寒害研究存在关键概念混淆、实际生产尚不能应用外源物质提高香蕉抗寒能力、香蕉生产主要分布于种植的次适宜区、香蕉寒害后产供失衡、缺乏抗寒品种等问题,并针对存在的问题提出了相应对策,以期为香蕉寒害的研究、防寒栽培、灾后恢复生产及抗寒品种选育提供参考依据.

  9. [Visible/NIR analysis of fat, protein and water in chilled pork].

    Science.gov (United States)

    Liu, Kui-Wu; Cheng, Fang; Lin, Hong-Jian; Sun, Tong; Xu, Kai; Hu, Lei-Xiu; Ying, Yi-Bin; Xu, Hui-Rong

    2009-01-01

    Fat, protein and water were determined by visible and NIR transmittance spectroscopy in chilled pork. After preprocessed by multiplicative scatter correction (MSC), the quantitative analysis models were developed based on the original, first derivative and second derivative spectra by using partial least squares (PLS) at the temperatures of 0-4 degrees C and 20 degrees C, respectively. By comparing the correlation coefficient (r), RMSEC, and SEP, we found that the first derivative model was the best, and the performance for 0-4 degrees C was better than that for 20 degrees C. At 0-4 degrees C and 20 degrees C, the correlation coefficients were 0.950 and 0.924 for fat, 0.713 and 0.455 for protein and 0.944 and 0.914 for water respectively, SEP values were 2.41 and 2.95 for fat, 5.44 and 4.25 for protein, and 2.37 and 2.38 for water respectively. The results showed that the visible and NIR analysis could measure the fat and water contents in chilled pork well, but was bad for protein, and this was caused by processing line of chilled pork. What's more, the spectrum offset was found in the original spectra at about 770 nm to be about 10 nm.

  10. Hydrogen sulfide is involved in the chilling stress response in Vitis vinifera L.

    Directory of Open Access Journals (Sweden)

    Peining Fu

    2013-11-01

    Full Text Available Hydrogen sulfide (H2S is an important signaling molecule involved in several stress-resistance processes in plants, such as drought and heavy metal stresses. However, little is known about the roles of H2S in responses to chilling stress. In this paper, we demonstrated that chilling stress enhance the H2S levels, the H2S synthetase (L-/D-cysteine desulfhydrase, L/DCD activities, and the expression of L/DCD gene in Vitis vinifera L. ‘F-242’. Furthermore, the seedlings were treated with sodium hydrosulfide (NaHS, a H2S donor and hypotaurine (HT, a H2S scavenger at 4°C to examine the effects of exogenous H2S on grape. The results revealed that the high activity of superoxide dismutase and enhanced expression of VvICE1 and VvCBF3 genes, but low level of super oxide anion radical, malondialdehyde content and cell membrane permeability were detected after addition of NaHS. In contrast, HT treatment displayed contrary effect under the chilling temperature. Taken together, these data suggested that H2S might be directly involved in the cold signal transduction pathway of grape.

  11. Extending Shelf Life of Chilled Pork by Combination of Chitosan Coating With Spice Extracts

    Institute of Scientific and Technical Information of China (English)

    XIA Xiufang; KONG Baohua

    2008-01-01

    The effects of spices (cinnamon, rosemary, clove) extracts and chitosan on microbiological growth, drip loss, color, and lipid oxidation of fresh chilled meat stored for 28 days at 4"C were investigated. There were four treatments: control, coated with spices(cimmamon 1.5g·L-1+rosemary 1.5·L-1+colve 1.0 g·L-1),coated with 0.5% chitosan,coated with spices and chitosan.Chitosan coating resulted in significant inhibition of microbial growth (P<0.05), while the lowest microbial counts were obtained in the samples containing both chitosan and spices, indicating a possible synergistic effect. Chitosan and its combinations with spices also showed the most intense antioxidative effect when compared to the controls (P<0.05). Meanwhile, chitosan coating could decrease water loss and keep better color of chilled meat. The combined spice extracts and chitosan coating could effectively extend the shelf life of chilled meat.

  12. Growth crystallography of silicon phases in unmodified, impurity and chill modified Al-Si eutectic alloys

    International Nuclear Information System (INIS)

    In aluminium-silicon eutectic alloys the faceted silicon phase can have different morphologies and the solidification pattern can be changed by solidification conditions and by minor additions to the melt. The crystallography of eutectic silicon in the unmodified aluminium-silicon eutectic alloys has been studied in detail by scanning (SEM) and transmission techniques. Modification of the silicon by strontium and treatment of the aluminium-silicon alloys by antimony as well as the effect of chill modification have also been examined. The growth modes of the observed morphologies are discussed. Strontium modification results in decreased spacing and increased undercooling and multiple twinning was observed in the silicon fibres at all growth rates. These observations are reconciled with a modification mechanism in which strontium adsorbs at the silicon growth front, poisoning growth steps operating during flake growth and creating lattice instabilities which result in multiple twinning. In chill modified fibres, however, only cozonal twinning was observed and the density of twins decreased as the growth rate increased. The growth mechanism of chill modified fibres is reconciled with a modification mechanism that assumes a faceted-non/faceted transition in the silicon phase

  13. Use of Aloe vera-based extender for chilling and freezing collared peccary (Pecari tajacu) semen.

    Science.gov (United States)

    Souza, A L P; Lima, G L; Peixoto, G C X; Silva, A M; Oliveira, M F; Silva, A R

    2016-05-01

    As an alternative for the conservation of collared peccary semen, this research aims at evaluating the use of Aloe vera (AV) extract as a cryoprotectant for semen chilling and freezing. Five ejaculates were divided in two aliquots that were diluted in Tris plus egg yolk (EY; 20%) or AV extract (20%) and chilled at 5 °C. In both treatments, an adequate semen conservation was achieved and values closer to 40% motile sperm with viability and osmotic response ranging from 20% to 40%, and normal morphology of 80% were found after 36 hours of storage. Moreover, 12 other ejaculates were diluted in Tris plus EY (20%) or AV extract (5, 10, or 20%) and glycerol (3%). Samples were frozen in liquid nitrogen and thawed after 1 week. After thawing, all the treatments containing EY or AV provided similar values for sperm morphology, viability, osmotic response, membrane integrity, sperm motility, amplitude of lateral head, beat cross frequency, and rapid, low, and static subpopulations, but the highest values for straightness and the lowest values for curvilinear velocity were found using 20% AV (P < 0.05). In conclusion, we found that AV extract at a 20% concentration could be used as an alternative substitute to EY in the formulation of Tris extenders for collared peccaries' semen chilling or freezing. PMID:26830302

  14. Experimental investigation on chill-down process of cryogenic flow line

    Science.gov (United States)

    Jin, Lingxue; Park, Changgi; Cho, Hyokjin; Lee, Cheonkyu; Jeong, Sangkwon

    2016-10-01

    This paper describes the cryogenic chill-down experiments that are conducted on a 12.7 mm outer diameter, 1.25 mm wall thickness and 7 m long stainless steel horizontal pipe with liquid nitrogen (LN2). The pipe is vacuum insulated during the experiment to minimize the heat leak from room temperature and to enable one to numerically simulate the process easily. The temperature and the pressure profiles of the chill-down line are obtained at the location which is 5.5 m in a distance from the pipe inlet. The mass flux range is approximately from 19 kg/m2 s to 49 kg/m2 s, which corresponds to the Reynolds numbers range from 1469 to 5240. The transient histories of temperature, pressure and mass flow rate during the line chill-down process are monitored, and the heat transfer coefficient and the heat flux are computed by an inverse problem solving method. The amplitude of the pressure oscillation and the oscillating period become larger and longer at higher pressure conditions. In the low mass flux conditions, the critical heat flux in horizontal pipes is not sensitive to mass flux, and is higher than that in vertical pipes. Kutateladze's correlation with the constant coefficient, B = 0.029 , well matches the experimental data in the current work. In nucleate flow boiling regime, heat transfer coefficient, h , is proportional to (q″)n , and n is equal to 0.7.

  15. Analytical Method for Differentiation of Chilled and Frozen-Thawed Chicken Meat

    Directory of Open Access Journals (Sweden)

    Ivanova Ivelina

    2014-12-01

    Full Text Available : Chilled and frozen chicken breast and thigh meat were stored at +4±1 oC and - 20±1 oC, respectively. Maillard reaction between ribose and meat proteins of the chicken samples was initiated. The changes in the ribose-induced Maillard reaction rate during chilled and frozen storage of chicken meat were evaluated on the bases of corrected absorbance values (A420* and bovine melanoidin equivalent values (mg BME/g. Application of BME as a measure of ribose-induced Maillard reaction rate enables comparability of the data obtained by different spectrophotometers. It was found that the BME values of chicken meat frozen stored for more than 15 days were significantly (P<0.05 lower than BME values of chilled-stored samples. According to the suggested threshold limit values the chicken thigh and breast meat with BME values lower than 30 mg BME/g and 51 mg BME/g, respectively could be classified as frozen-thawed.

  16. Use of Aloe vera-based extender for chilling and freezing collared peccary (Pecari tajacu) semen.

    Science.gov (United States)

    Souza, A L P; Lima, G L; Peixoto, G C X; Silva, A M; Oliveira, M F; Silva, A R

    2016-05-01

    As an alternative for the conservation of collared peccary semen, this research aims at evaluating the use of Aloe vera (AV) extract as a cryoprotectant for semen chilling and freezing. Five ejaculates were divided in two aliquots that were diluted in Tris plus egg yolk (EY; 20%) or AV extract (20%) and chilled at 5 °C. In both treatments, an adequate semen conservation was achieved and values closer to 40% motile sperm with viability and osmotic response ranging from 20% to 40%, and normal morphology of 80% were found after 36 hours of storage. Moreover, 12 other ejaculates were diluted in Tris plus EY (20%) or AV extract (5, 10, or 20%) and glycerol (3%). Samples were frozen in liquid nitrogen and thawed after 1 week. After thawing, all the treatments containing EY or AV provided similar values for sperm morphology, viability, osmotic response, membrane integrity, sperm motility, amplitude of lateral head, beat cross frequency, and rapid, low, and static subpopulations, but the highest values for straightness and the lowest values for curvilinear velocity were found using 20% AV (P < 0.05). In conclusion, we found that AV extract at a 20% concentration could be used as an alternative substitute to EY in the formulation of Tris extenders for collared peccaries' semen chilling or freezing.

  17. Antimicrobial Activities of Nisin, Tea Polyphenols, and Chitosan and their Combinations in Chilled Mutton.

    Science.gov (United States)

    He, Li; Zou, Likou; Yang, Qianru; Xia, Jinghua; Zhou, Kang; Zhu, Yuanting; Han, Xinfeng; Pu, Biao; Hu, Bin; Deng, Wenwen; Liu, Shuliang

    2016-06-01

    Antimicrobial activities of nisin, tea polyphenols (TPs), and chitosan, and their combinations were evaluated against both Gram-positive bacteria (GPB) and Gram-negative bacteria (GNB) by the agar dilution method. Results showed that the MIC of nisin was 2.44 to 1250 mg/L for GPB and reached 5000 mg/L for GNB. The MICs of TPs and chitosan were 313 to 625 mg/L and 469 mg/L for GNB, and 156 to 5000 mg/L and 234 to 938 mg/L for GPB, respectively. These results indicated that TPs and chitosan exhibited inhibitory effects against both GPB and GNB, whereas nisin inhibited the growth of GPB only. Based on the orthogonal test of their MICs, and evaluation of preservative effect and sensory attributes in chilled mutton, the optimum combination was chosen as 0.625, 0.313, and 3.752 g/L for nisin, TPs, and chitosan, respectively. By using the optimum treatment, the shelf life of chilled mutton was extended from 6 to 18 d at 4 °C in the preservative film packages. These results indicate that the combination of nisin, TPs, and chitosan could be used as preservatives to efficiently inhibit the growth of spoilage microorganisms and pathogens in meat, thus improving the safety and shelf life of chilled mutton. PMID:27096939

  18. Full-scale chilled pipeline frost heave testing, Fairbanks, Alaska, USA

    Energy Technology Data Exchange (ETDEWEB)

    Hazen, B. [Northern Engineering and Scientific, Anchorage, AK (United States); Isaacs, R.M. [RMI Associates, Camano Island, WA (United States); Myrick, J.E. [Myrick International, Tyler, TX (United States)

    2010-07-01

    This paper discussed a chilled pipeline frost-heave testing facility that was developed to simulate and record the rate of frost heave and frost-bulb growth for a buried, chilled pipeline in frost-susceptible soil and to determine the effectiveness of different mitigation techniques. The test facility, which was established near Fairbanks, Alaska, in 1979, has 10 test sections using 1.22-metre-diameter pipe. The testing involved un-insulated, insulated, and insulated with over-excavation and gravel berm configurations as well as the frost heave of the chilled pipeline. The test facility was described in detail. Frost heave and frost-bulb growth measurements from the first 10 months of testing were presented, as these are the first data to enter the public domain. The testing was undertaken to investigate the frost-heave relationships between sections, to better understand frost heave in permafrost, to explore possible mitigation options, and to advance the predicative capabilities of frost heave models. 12 refs., 1 tab., 17 figs.

  19. Reading Between the Panels: A Review of Barbara Postema’s Narrative Structure in Comics: Making Sense of Fragments

    Directory of Open Access Journals (Sweden)

    Paul Fisher Davies

    2015-09-01

    Full Text Available Narrative Structure in Comics builds on Postema’s PhD thesis to present for a more general audience her focus on the ‘gap’ in comics and its place in the process of reading graphic narrative, from the detailed textual level up to the level of narrative structure overall. Postema's readings of comics texts are well-argued and illuminating; the breadth of theory brought together here, and the range of exemplars used in analysis, make Narrative Structure in Comics an invaluable reader for those interested in engaging with the practical application of medium-specific theory to comics texts themselves.

  20. Reading Between the Panels: A Review of Barbara Postema’s Narrative Structure in Comics: Making Sense of Fragments

    Directory of Open Access Journals (Sweden)

    Paul Fisher Davies

    2015-09-01

    Full Text Available 'Narrative Structure in Comics' builds on Postema’s PhD thesis to present for a more general audience her focus on the ‘gap’ in comics and its place in the process of reading graphic narrative, from the detailed textual level up to the level of narrative structure overall. Postema's readings of comics texts are well-argued and illuminating; the breadth of theory brought together here, and the range of exemplars used in analysis, make 'Narrative Structure in Comics' an invaluable reader for those interested in engaging with the practical application of medium-specific theory to comics texts themselves.