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Sample records for heating induced jam

  1. Spin jam induced by quantum fluctuations in a frustrated magnet.

    Science.gov (United States)

    Yang, Junjie; Samarakoon, Anjana; Dissanayake, Sachith; Ueda, Hiroaki; Klich, Israel; Iida, Kazuki; Pajerowski, Daniel; Butch, Nicholas P; Huang, Q; Copley, John R D; Lee, Seung-Hun

    2015-09-15

    Since the discovery of spin glasses in dilute magnetic systems, their study has been largely focused on understanding randomness and defects as the driving mechanism. The same paradigm has also been applied to explain glassy states found in dense frustrated systems. Recently, however, it has been theoretically suggested that different mechanisms, such as quantum fluctuations and topological features, may induce glassy states in defect-free spin systems, far from the conventional dilute limit. Here we report experimental evidence for existence of a glassy state, which we call a spin jam, in the vicinity of the clean limit of a frustrated magnet, which is insensitive to a low concentration of defects. We have studied the effect of impurities on SrCr9pGa12-9pO19 [SCGO(p)], a highly frustrated magnet, in which the magnetic Cr(3+) (s = 3/2) ions form a quasi-2D triangular system of bipyramids. Our experimental data show that as the nonmagnetic Ga(3+) impurity concentration is changed, there are two distinct phases of glassiness: an exotic glassy state, which we call a spin jam, for the high magnetic concentration region (p > 0.8) and a cluster spin glass for lower magnetic concentration (p < 0.8). This observation indicates that a spin jam is a unique vantage point from which the class of glassy states of dense frustrated magnets can be understood.

  2. Jamming transitions induced by an attraction in pedestrian flow

    Science.gov (United States)

    Kwak, Jaeyoung; Jo, Hang-Hyun; Luttinen, Tapio; Kosonen, Iisakki

    2017-08-01

    We numerically study jamming transitions in pedestrian flow interacting with an attraction, mostly based on the social force model for pedestrians who can join the attraction. We formulate the joining probability as a function of social influence from others, reflecting that individual choice behavior is likely influenced by others. By controlling pedestrian influx and the social influence parameter, we identify various pedestrian flow patterns. For the bidirectional flow scenario, we observe a transition from the free flow phase to the freezing phase, in which oppositely walking pedestrians reach a complete stop and block each other. On the other hand, a different transition behavior appears in the unidirectional flow scenario, i.e., from the free flow phase to the localized jam phase and then to the extended jam phase. It is also observed that the extended jam phase can end up in freezing phenomena with a certain probability when pedestrian flux is high with strong social influence. This study highlights that attractive interactions between pedestrians and an attraction can trigger jamming transitions by increasing the number of conflicts among pedestrians near the attraction. In order to avoid excessive pedestrian jams, we suggest suppressing the number of conflicts under a certain level by moderating pedestrian influx especially when the social influence is strong.

  3. Beam induced RF heating

    CERN Document Server

    Salvant, B; Arduini, G; Assmann, R; Baglin, V; Barnes, M J; Bartmann, W; Baudrenghien, P; Berrig, O; Bracco, C; Bravin, E; Bregliozzi, G; Bruce, R; Bertarelli, A; Carra, F; Cattenoz, G; Caspers, F; Claudet, S; Day, H; Garlasche, M; Gentini, L; Goddard, B; Grudiev, A; Henrist, B; Jones, R; Kononenko, O; Lanza, G; Lari, L; Mastoridis, T; Mertens, V; Métral, E; Mounet, N; Muller, J E; Nosych, A A; Nougaret, J L; Persichelli, S; Piguiet, A M; Redaelli, S; Roncarolo, F; Rumolo, G; Salvachua, B; Sapinski, M; Schmidt, R; Shaposhnikova, E; Tavian, L; Timmins, M; Uythoven, J; Vidal, A; Wenninger, J; Wollmann, D; Zerlauth, M

    2012-01-01

    After the 2011 run, actions were put in place during the 2011/2012 winter stop to limit beam induced radio frequency (RF) heating of LHC components. However, some components could not be changed during this short stop and continued to represent a limitation throughout 2012. In addition, the stored beam intensity increased in 2012 and the temperature of certain components became critical. In this contribution, the beam induced heating limitations for 2012 and the expected beam induced heating limitations for the restart after the Long Shutdown 1 (LS1) will be compiled. The expected consequences of running with 25 ns or 50 ns bunch spacing will be detailed, as well as the consequences of running with shorter bunch length. Finally, actions on hardware or beam parameters to monitor and mitigate the impact of beam induced heating to LHC operation after LS1 will be discussed.

  4. Traffic jams induce dynamical phase transition in spatial rock-paper-scissors game

    Science.gov (United States)

    Nagatani, Takashi; Ichinose, Genki; Tainaka, Kei-ichi

    2018-02-01

    Spatial and temporal behaviors of the rock-paper-scissors (RPS) game is key to understanding not only biodiversity but also a variety of cyclic systems. It has been demonstrated that, in the stochastic cellular automaton of RPS game, three species cannot survive on one-dimensional (1-d) lattice; only a single species survives. Previous studies have shown that three species are able to coexist if the migration of species is considered. However, their definitions of migration are the swapping of two species or the random walk of species, which rarely occurs in nature. Here, we investigate the effect of migration by using the 1-d lattice traffic model in which species can move rightward if the site ahead is empty. Computer simulations reveal that three species can survive at the same time within the wide range of parameter values. At low densities, all species can coexist. In contrast, the extinction of two species occurs if the density exceeds the critical limit of the jamming transition. This dynamical phase transition between the coexistence and single (non-coexistence) phase clearly separates due to the self-organized pattern: condensation and rarefaction in the stripe-pattern of three species.

  5. Shear-induced ordering and crystallization of jammed suspensions of soft particles glasses

    Science.gov (United States)

    Khabaz, Fardin; Liu, Tianfei; Cloitre, Michel; Bonnecaze, Roger T.

    2017-09-01

    The microstructure and shear rheology of highly concentrated, jammed suspensions of soft particles are shown to depend on polydispersity and shear rate from computational simulations. Rich behavior is observed depending on the degree of polydispersity and the shear rate. Glassy suspensions with a low degree of polydispersity evolve to face-centered cubic and hexagonal close-packed structures at low and high shear rates, respectively. The structural rearrangement occurs over several units of strain and reduces the shear stress and elastic energy. Suspensions with a higher degree of polydispersity exhibit a microstructural transition from a glass to a layeredlike structure for sufficiently high shear rates. In this case, the soft particles first rearrange themselves in the flow-vorticity plane during an induction time (or strain) before layers parallel to the flow-vorticity plane are formed. The induction strain decays exponentially with shear rate revealing that the devitrification of monodisperse and polydisperse suspensions is a shear-activated process. Finally, a generic dynamical state diagram is found that depends on the polydispersity and the ratio of viscous to elastic forces due to shear.

  6. Nanocrystallinity induced by heating

    DEFF Research Database (Denmark)

    Mørup, Steen; Meaz, T.M.; Bender Koch, C.

    1997-01-01

    Samples of akaganeite (beta-FeOOH) and goethite (alpha-FeOOH) have been studied after heating at various temperatures up to 800 C. X-ray diffraction and Mossbauer spectroscopy measurements showed that slightly below the temperatures at which the samples transform to hematite (alpha-Fe2O3...

  7. Shear jamming in granular experiments without basal friction

    NARCIS (Netherlands)

    Zheng, H.; Dijksman, J.A.; Behringer, R.P.

    2014-01-01

    Jammed states of frictional granular systems can be induced by shear strain at densities below the isostatic jamming density $(\\\\phi_c)$ . It remains unclear, however, how much friction affects this so-called shear jamming. Friction appears in two ways in this type of experiment: friction between

  8. Jamitons: Phantom Traffic Jams

    Science.gov (United States)

    Kowszun, Jorj

    2013-01-01

    Traffic on motorways can slow down for no apparent reason. Sudden changes in speed by one or two drivers can create a chain reaction that causes a traffic jam for the vehicles that are following. This kind of phantom traffic jam is called a "jamiton" and the article discusses some of the ways in which traffic engineers produce…

  9. Ways of the Jam

    DEFF Research Database (Denmark)

    Brinck, Lars

    In the PhD-dissertation Ways of the Jam I investigate jamming and learning as profoundly collective and improvisational matters. Bridging a theory of funk jamming with situated learning theoretical analyses of New Orleans second line, everyday leadership, and of a studio recording session...... demonstrate how looking at human activity from a jamming perspective enhances our understanding of learning as a complex collective and improvisational process. Ways of the Jam demonstrates how learning is a matter of changing improvisational participation in changing practice in analytically inseparable ways......, circumscribed by what practice is ‘about’. This leads to the dissertation’s closing argument: putting what practice is about and the collectivity of practice first enhances important aspects of learning. The dissertation offers a set of theoretical as well as empirical speculations on this ‘aboutness...

  10. Digital Communications Jamming

    National Research Council Canada - National Science Library

    Sen, Cem

    2000-01-01

    ...) and different types of jamming signals by using MATLAB Communications Toolbox and Simulink. The theoretical results are available for the effect of AWGN on the performance of digital communication systems...

  11. The nutritional composition of fruit jams in the Malaysian market

    Directory of Open Access Journals (Sweden)

    M.N. Mohd Naeem

    2017-01-01

    Full Text Available Fruit jams are preserved fruits and sugars normally canned or sealed for long-term storage. Jam making involves the disruption of the fruit tissue followed by heating with added water and sugar to activate its pectin before being put into containers. Processes that expose foods to high levels of heat may cause some nutrient loss. Hence, the objective of this study was to evaluate the nutritional composition of four commonly consumed fruit jams that are available in the Malaysian market. Different brands (n = 6 of each type of fruit jams (grape, apricot, blueberry and strawberry were sampled from supermarkets in Klang Valley, Malaysia. The sampling method used was stratified random sampling. The fruit jams were analyzed for the presence of 27 important nutrients using Association of Official Agricultural Chemists (AOAC official methods of analysis. This study showed that fruit jams are a good source of energy and carbohydrate. The fruits jams have very low levels of fatty acids. Fruit jams may provide an affordable and convenient source of energy and carbohydrate. The data can be utilized to contribute to the enhancement of Malaysia Food Composition Database.

  12. Jamming and learning

    DEFF Research Database (Denmark)

    Brinck, Lars

    2017-01-01

    -academy students ‘sitting in’. Fieldwork was documented through sound recordings, diaries, and field notes from participant observation and informal interviews. Analyses apply a situated learning theoretical perspective on the band members’ as well as the students’ participation and reveal important learning......This article reports a long-term ethnographic study on jamming and learning from an entwined artistic and educational perspective. The study investigates aspects of learning during a professional band’s jamming and recording eight groove-jazz frameworks and a series of subsequent concerts with pre...... to take place. Analyses also indicate the musicians’ changing participation being analytically inseparable from the changing music itself. The study’s final argument is two-fold: Revitalising jamming as a studio-recording practice within popular music highlights important aspects of professional musicians...

  13. Jamming transitions in cancer

    Science.gov (United States)

    Oswald, Linda; Grosser, Steffen; Smith, David M.; Käs, Josef A.

    2017-12-01

    The traditional picture of tissues, where they are treated as liquids defined by properties such as surface tension or viscosity has been redefined during the last few decades by the more fundamental question: under which conditions do tissues display liquid-like or solid-like behaviour? As a result, basic concepts arising from the treatment of tissues as solid matter, such as cellular jamming and glassy tissues, have shifted into the current focus of biophysical research. Here, we review recent works examining the phase states of tissue with an emphasis on jamming transitions in cancer. When metastasis occurs, cells gain the ability to leave the primary tumour and infiltrate other parts of the body. Recent studies have shown that a linkage between an unjamming transition and tumour progression indeed exists, which could be of importance when designing surgery and treatment approaches for cancer patients.

  14. Optimisation of microwave-assisted processing in production of pineapple jam

    Science.gov (United States)

    Ismail, Nur Aisyah Mohd; Abdullah, Norazlin; Muhammad, Norhayati

    2017-10-01

    Pineapples are available all year round since they are unseasonal fruits. Due to the continuous harvesting of the fruit, the retailers and farmers had to find a solution such as the processing of pineapple into jam, to treat the unsuccessfully sold pineapples. The direct heating of pineapple puree during the production of pineapple jam can cause over degradation of quality of the fresh pineapple. Thus, this study aims to optimise the microwave-assisted processing conditions for producing pineapple jam which could reduce water activity and meets minimum requirement for pH and total soluble solids contents of fruit jam. The power and time of the microwave processing were chosen as the factors, while the water activity, pH and total soluble solids (TSS) content of the pineapple jam were determined as responses to be optimised. The microwave treatment on the pineapple jam was able to give significant effect on the water activity and TSS content of the pineapple jam. The optimum power and time for the microwave processing of pineapple jam is 800 Watt and 8 minutes, respectively. The use of domestic microwave oven for the pineapple jam production results in acceptable pineapple jam same as conventional fruit jam sold in the marketplace.

  15. Magnetic induced heating of nanoparticle solutions

    Energy Technology Data Exchange (ETDEWEB)

    Murph, S. Hunyadi [Savannah River Site (SRS), Aiken, SC (United States); Univ. of Georgia, Athens, GA (United States); Brown, M. [Savannah River Site (SRS), Aiken, SC (United States); Coopersmith, K. [Savannah River Site (SRS), Aiken, SC (United States); Fulmer, S. [Savannah River Site (SRS), Aiken, SC (United States); Sessions, H. [Savannah River Site (SRS), Aiken, SC (United States); Ali, M. [Univ. of South Carolina, Columbia, SC (United States)

    2016-12-02

    Magnetic induced heating of nanoparticles (NP) provides a useful advantage for many energy transfer applications. This study aims to gain an understanding of the key parameters responsible for maximizing the energy transfer leading to nanoparticle heating through the use of simulations and experimental results. It was found that magnetic field strength, NP concentration, NP composition, and coil size can be controlled to generate accurate temperature profiles in NP aqueous solutions.

  16. Traffic jams without bottlenecks—experimental evidence for the physical mechanism of the formation of a jam

    Science.gov (United States)

    Sugiyama, Yuki; Fukui, Minoru; Kikuchi, Macoto; Hasebe, Katsuya; Nakayama, Akihiro; Nishinari, Katsuhiro; Tadaki, Shin-ichi; Yukawa, Satoshi

    2008-03-01

    A traffic jam on a highway is a very familiar phenomenon. From the physical viewpoint, the system of vehicular flow is a non-equilibrium system of interacting particles (vehicles). The collective effect of the many-particle system induces the instability of a free flow state caused by the enhancement of fluctuations, and the transition to a jamming state occurs spontaneously if the average vehicle density exceeds a certain critical value. Thus, a bottleneck is only a trigger and not the essential origin of a traffic jam. In this paper, we present the first experimental evidence that the emergence of a traffic jam is a collective phenomenon like 'dynamical' phase transitions and pattern formation in a non-equilibrium system. We have performed an experiment on a circuit to show the emergence of a jam with no bottleneck. In the initial condition, all the vehicles are moving, homogeneously distributed on the circular road, with the same velocity. The average density of the vehicles is prepared for the onset of the instability. Even a tiny fluctuation grows larger and then the homogeneous movement cannot be maintained. Finally, a jam cluster appears and propagates backward like a solitary wave with the same speed as that of a jam cluster on a highway.

  17. Heat induces gene amplification in cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Bin, E-mail: yanbin@mercyhealth.com [Department of Radiation Oncology, University of Mississippi Medical Center, Jackson, MS 39213 (United States); Mercy Cancer Center, Mercy Medical Center-North Iowa, Mason City, IA 50401 (United States); Ouyang, Ruoyun [Department of Respiratory Medicine, The Second Xiangya Hospital, Xinagya School of Medicine, Central South University, Changsha 410011 (China); Huang, Chenghui [Department of Radiation Oncology, University of Mississippi Medical Center, Jackson, MS 39213 (United States); Department of Oncology, The Third Xiangya Hospital, Xinagya School of Medicine, Central South University, Changsha 410013 (China); Liu, Franklin [Department of Radiation Oncology, Duke University Medical Center, Durham, NC 27710 (United States); Neill, Daniel [Department of Radiation Oncology, University of Mississippi Medical Center, Jackson, MS 39213 (United States); Li, Chuanyuan [Dermatology, Duke University Medical Center, Durham, NC 27710 (United States); Dewhirst, Mark [Department of Radiation Oncology, Duke University Medical Center, Durham, NC 27710 (United States)

    2012-10-26

    Highlights: Black-Right-Pointing-Pointer This study discovered that heat exposure (hyperthermia) results in gene amplification in cancer cells. Black-Right-Pointing-Pointer Hyperthermia induces DNA double strand breaks. Black-Right-Pointing-Pointer DNA double strand breaks are considered to be required for the initiation of gene amplification. Black-Right-Pointing-Pointer The underlying mechanism of heat-induced gene amplification is generation of DNA double strand breaks. -- Abstract: Background: Hyperthermia plays an important role in cancer therapy. However, as with radiation, it can cause DNA damage and therefore genetic instability. We studied whether hyperthermia can induce gene amplification in cancer cells and explored potential underlying molecular mechanisms. Materials and methods: (1) Hyperthermia: HCT116 colon cancer cells received water-submerged heating treatment at 42 or 44 Degree-Sign C for 30 min; (2) gene amplification assay using N-(phosphoacetyl)-L-aspartate (PALA) selection of cabamyl-P-synthetase, aspartate transcarbarmylase, dihydro-orotase (cad) gene amplified cells; (3) southern blotting for confirmation of increased cad gene copies in PALA-resistant cells; (4) {gamma}H2AX immunostaining to detect {gamma}H2AX foci as an indication for DNA double strand breaks. Results: (1) Heat exposure at 42 or 44 Degree-Sign C for 30 min induces gene amplification. The frequency of cad gene amplification increased by 2.8 and 6.5 folds respectively; (2) heat exposure at both 42 and 44 Degree-Sign C for 30 min induces DNA double strand breaks in HCT116 cells as shown by {gamma}H2AX immunostaining. Conclusion: This study shows that heat exposure can induce gene amplification in cancer cells, likely through the generation of DNA double strand breaks, which are believed to be required for the initiation of gene amplification. This process may be promoted by heat when cellular proteins that are responsible for checkpoints, DNA replication, DNA repair and

  18. Biophoton emission induced by heat shock.

    Directory of Open Access Journals (Sweden)

    Katsuhiro Kobayashi

    Full Text Available Ultraweak biophoton emission originates from the generation of reactive oxygen species (ROS that are produced in mitochondria as by-products of cellular respiration. In healthy cells, the concentration of ROS is minimized by a system of biological antioxidants. However, heat shock changes the equilibrium between oxidative stress and antioxidant activity, that is, a rapid rise in temperature induces biophoton emission from ROS. Although the rate and intensity of biophoton emission was observed to increase in response to elevated temperatures, pretreatment at lower high temperatures inhibited photon emission at higher temperatures. Biophoton measurements are useful for observing and evaluating heat shock.

  19. Quantum Heat Engine Using Electromagnetically Induced Transparency

    Science.gov (United States)

    Zou, Yueyang; Jiang, Yue; Mei, Yefeng; Guo, Xianxin; Du, Shengwang

    2017-08-01

    We report an experiment demonstrating the generation of directional thermal radiation with a spectral brightness that is about 9 times greater than that of the ambient pumping reservoir. The experiment is based on the recent proposal for a nontraditional quantum heat engine and uses cold Rb atoms, electromagnetically induced transparency, and photon correlation spectroscopy [Phys. Rev. A 94, 053859 (2016), 10.1103/PhysRevA.94.053859].

  20. Heat pump processes induced by laser radiation

    Science.gov (United States)

    Garbuny, M.; Henningsen, T.

    1980-01-01

    A carbon dioxide laser system was constructed for the demonstration of heat pump processes induced by laser radiation. The system consisted of a frequency doubling stage, a gas reaction cell with its vacuum and high purity gas supply system, and provisions to measure the temperature changes by pressure, or alternatively, by density changes. The theoretical considerations for the choice of designs and components are dicussed.

  1. Biophysics: Life in a jam

    Science.gov (United States)

    Gokhale, Shreyas; Gore, Jeff

    2016-08-01

    Jammed states in growing yeast populations share intriguing similarities with amorphous solids, despite being generated through self-replication. The impact this behaviour has on cell division highlights one way that physical forces regulate biological function.

  2. Hidden geometry of traffic jamming

    Science.gov (United States)

    Andjelković, Miroslav; Gupte, Neelima; Tadić, Bosiljka

    2015-05-01

    We introduce an approach based on algebraic topological methods that allow an accurate characterization of jamming in dynamical systems with queues. As a prototype system, we analyze the traffic of information packets with navigation and queuing at nodes on a network substrate in distinct dynamical regimes. A temporal sequence of traffic density fluctuations is mapped onto a mathematical graph in which each vertex denotes one dynamical state of the system. The coupling complexity between these states is revealed by classifying agglomerates of high-dimensional cliques that are intermingled at different topological levels and quantified by a set of geometrical and entropy measures. The free-flow, jamming, and congested traffic regimes result in graphs of different structure, while the largest geometrical complexity and minimum entropy mark the edge of the jamming region.

  3. Making Black Bloody Rosella Jam

    Directory of Open Access Journals (Sweden)

    Ili Farhana

    2016-08-01

    Full Text Available The rosella (or roselle plant originated in West Africa, but has been cultivated throughout Africa, Asia and Australia. Not only can rosella be used to make teas and jams, but every part of the plant is edible; the young leaves can be eaten raw and make great salads. Rosella is a type of hibiscus, and it has a beautiful pink flower. Although the whole plant is edible, it is the calyx (the bright red fruit that is used to make syrups, teas or jams. If you eat it fresh, straight off the stalk, it has a sour taste. Inside the calyx is a round seed pod. If it is left to mature, it will turn brown. When dry it provides the mature seeds for the next planting. At Kebun Setaman Pejeng, our small-scale community arm and learning centre at Bamjar Panglan, Pejeng, on the island of Bali, we harvest rosella to make jam.

  4. Magnetorheological Shear Flow Near Jamming

    Science.gov (United States)

    Vågberg, Daniel; Tighe, Brian

    2015-03-01

    Flow in magnetorheological (MR) fluids and systems near jamming both display hallmarks of complex fluid rheology, including yield stresses and shear thinning viscosities. They are also tunable, which means that both phenomena can be used as a switching mechanism in ``smart'' fluids, i.e. fluids where properties can be tuned rapidly and reversibly by changing external parameters. We use numerical simulations to investigate the rheological properties of MR fluids close to the jamming transition as a function of the applied field and volume fraction. We are especially interested in the crossover region where both phenomena are needed to describe the observed dynamics. Funded by the Dutch Organization for Scientific Research (NWO).

  5. Overexpression of JAM-A in non-small cell lung cancer correlates with tumor progression.

    Directory of Open Access Journals (Sweden)

    Min Zhang

    Full Text Available The objective of the current study was to determine the clinical significance of junctional adhesion molecule A (JAM-A in patients with non-small cell lung cancer (NSCLC and the biological function of JAM-A in NSCLC cell lines. We showed that JAM-A is predominantly expressed in cell membranes and high expression of JAM-A occurred in 37% of lung tumor specimens compared to corresponding normal tissues. High expression of JAM-A was significantly correlated with TNM stage (P = 0.021, lymph node metastasis (P = 0.007, and decreased overall survival (P = 0.02, In addition, we observed that silencing JAM-A by small interfering RNA inhibited tumor cell proliferation and induced cell cycle arrest at the G1/S boundary. Western blotting analysis revealed that knockdown of JAM-A decreased the protein levels of cyclin D1, CDK4, 6, and P-Rb. Thus, JAM-A plays an important role in NSCLC progression.

  6. Love triangles, quantum fluctuations and spin jam

    Science.gov (United States)

    Lee, Seung-Hun

    When magnetic moments are interacting with each other in a situation resembling that of complex love triangles, called frustration, a large set of states that are energetically equivalent emerge. This leads to exotic spin states such as spin liquid and spin ice. Recently, we presented evidence for the existence of a topological glassy state, that we call spin jam, induced by quantum fluctuations. The case in point is SrCr9pGa12-9pO19 (SCGO(p)), a highly frustrated magnet, in which the magnetic Cr ions form a quasi-two-dimensional triangular system of bi-pyramids. This system has been an archetype in search for exotic spin states. Understanding the nature of the state has been a great intellectual challenge. Our new experimental data and theoretical spin jam model provide for the first time a coherent understanding of the phenomenon. Furthermore, the findings strongly support the possible existence of purely topological glassy states. Reference:

  7. Endocytic reawakening of motility in jammed epithelia

    Science.gov (United States)

    Malinverno, Chiara; Corallino, Salvatore; Giavazzi, Fabio; Bergert, Martin; Li, Qingsen; Leoni, Marco; Disanza, Andrea; Frittoli, Emanuela; Oldani, Amanda; Martini, Emanuele; Lendenmann, Tobias; Deflorian, Gianluca; Beznoussenko, Galina V.; Poulikakos, Dimos; Ong, Kok Haur; Uroz, Marina; Trepat, Xavier; Parazzoli, Dario; Maiuri, Paolo; Yu, Weimiao; Ferrari, Aldo; Cerbino, Roberto; Scita, Giorgio

    2017-05-01

    Dynamics of epithelial monolayers has recently been interpreted in terms of a jamming or rigidity transition. How cells control such phase transitions is, however, unknown. Here we show that RAB5A, a key endocytic protein, is sufficient to induce large-scale, coordinated motility over tens of cells, and ballistic motion in otherwise kinetically arrested monolayers. This is linked to increased traction forces and to the extension of cell protrusions, which align with local velocity. Molecularly, impairing endocytosis, macropinocytosis or increasing fluid efflux abrogates RAB5A-induced collective motility. A simple model based on mechanical junctional tension and an active cell reorientation mechanism for the velocity of self-propelled cells identifies regimes of monolayer dynamics that explain endocytic reawakening of locomotion in terms of a combination of large-scale directed migration and local unjamming. These changes in multicellular dynamics enable collectives to migrate under physical constraints and may be exploited by tumours for interstitial dissemination.

  8. Jam Eyes: A Traffic Jam Awareness and Observation System Using Mobile Phones

    OpenAIRE

    Xing Zhang; Haigang Gong; Zongyi Xu; Jinchuan Tang; Bang Liu

    2012-01-01

    Traffic jam is a very common and very annoying thing in urban traffic. The most annoying part in traffic jams is not that you have to wait for a long time but that you do not even know how long you have to wait and what causes the traffic jam. However, the pain of being trapped in traffic jams seems to be neglected by existing research works; they put their focuses on either mathematical modeling or optimal routing for those not trapped in traffic jams. In this paper, we propose a traffic jam...

  9. Orienterend onderzoek naar het gehalte aan S02 in jam

    NARCIS (Netherlands)

    Worp, van der H.; Hollman, P.

    1981-01-01

    Onderzocht werden monsters jam van aardbeien, abrikozen en kersen van 2 verschillende merken van de kwaliteitsklassen extra jam, jam en halva jam. Tevens werden onderzocht 2 monsters bosbessen jam van Albert Heijn, omdat deze voorzien waren van nieuwe etikettering met o.a. als ingrediënten

  10. Chemical and sensorial properties of beetroot jam

    OpenAIRE

    Guiné, Raquel; Ana Rita, Roque; Gonçalves, Fernando; Correia, Paula

    2015-01-01

    The objective of the present work was to develop an innovative food product with nutritional properties as well as appealing organoleptic qualities. For this a jam was prepared on a basis of pear or apple, to which was added the water from boiling beetroot, without the addition of any conservatives. Five different jams were produced: pear jam, pear with beetroot, apple, apple with beetroot and finally apple with beetroot and cinnamon. The preparation of the products involved several tr...

  11. Heat shock transcription factors regulate heat induced cell death in a ...

    Indian Academy of Sciences (India)

    Madhu Sudhan

    2007-03-29

    Mar 29, 2007 ... Further, proteasome inhibition increased basal levels of HSF2 expression, which was further enhanced by heat shock (figure 4A2). To understand the importance of HSFs in the activation of heat induced autophagy, siRNA for both HSF1 and HSF2 were made and BC-8 cells were treated with these oligos.

  12. On the jamming power allocation for secure amplify-and-forward relaying via cooperative jamming

    KAUST Repository

    Park, Kihong

    2013-09-01

    In this paper, we investigate secure communications in two-hop wireless relaying networks with one eavesdropper. To prevent the eavesdropper from intercepting the source message, the destination sends an intended jamming noise to the relay, which is referred to as cooperative jamming. This jamming noise helps protecting the source message from being captured reliably at the eavesdropper, while the destination cancels its self-intended noise. According to the channel information available at the destination, we derive three jamming power allocation strategies to minimize the outage probability of the secrecy rate. In addition, we derive analytic results quantifying the jamming power consumption of the proposed allocation methods. © 1983-2012 IEEE.

  13. POTENTIALS OF TAMARINDUS INDICA (Linn) IN JAM ...

    African Journals Online (AJOL)

    S O Jimoh

    The unique sweet/sour flavor of the pulp makes it popular in domestic cooking ..... There was no difference in panelists' preference for the jam samples from ... are appreciable levels of vitamin C in tamarind jam which in the nutrition of humans.

  14. Stability of micronutrients and phytochemicals of grapefruit jam as affected by the obtention process.

    Science.gov (United States)

    Igual, M; García-Martínez, E; Camacho, M M; Martínez-Navarrete, N

    2016-04-01

    Fruits are widely revered for their micronutrient properties. They serve as a primary source of vitamins and minerals as well as of natural phytonutrients with antioxidant properties. Jam constitutes an interesting way to preserve fruit. Traditionally, this product is obtained by intense heat treatment that may cause irreversible loss of these bioactive compounds responsible for the health-related properties of fruits. In this work, different grapefruit jams obtained by conventional, osmotic dehydration (OD) without thermal treatment and/or microwave (MW) techniques were compared in terms of their vitamin, organic acid and phytochemical content and their stability through three months of storage. If compared with heating, osmotic treatments lead to a greater loss of organic acids and vitamin C during both processing and storage. MW treatments permit jam to be obtained which has a similar nutritional and functional value than that obtained when using a conventional heating method, but in a much shorter time. © The Author(s) 2015.

  15. Evidence of Vortex Jamming in Abrikosov Vortex Flux Flow Regime

    OpenAIRE

    Karapetrov, G.; Yefremenko, V.; Mihajlović, G; Pearson, J. E.; Iavarone, M.; Novosad, V.; Bader, S. D.

    2012-01-01

    We report on dynamics of non-local Abrikosov vortex flow in mesoscopic superconducting Nb channels. Magnetic field dependence of the non-local voltage induced by the flux flow shows that vortices form ordered vortex chains. Voltage asymmetry (rectification) with respect to the direction of vortex flow is evidence that vortex jamming strongly moderates vortex dynamics in mesoscopic geometries. The findings can be applied to superconducting devices exploiting vortex dynamics and vortex manipula...

  16. Relaxation of jammed colloidal suspensions after shear cessation.

    Science.gov (United States)

    Ianni, Francesca; Lasne, David; Sarcia, Régis; Hébraud, Pascal

    2006-07-01

    The dynamics of heterogeneities in a shear thickening, concentrated colloidal suspension is investigated through speckle visibility spectroscopy, a dynamic light scattering technique recently introduced [P. K. Dixon and D. J. Durian, Phys. Rev. Lett. 90, 184302 (2003)]. Formation of shear-induced heterogeneities is observed in the jamming regime, and their relaxation after shear cessation is monitored as a function of the applied shear stress. The relaxation time of these heterogeneities increases when a higher stress is applied.

  17. Bringing Drumsticks to Funerals. Jamming as Learning

    DEFF Research Database (Denmark)

    Brinck, Lars

    2012-01-01

    This ethnographically inspired field study employs social practice theory in analyzing New Orleans jazz and funk musicians' jamming as learning. Through analysis of participant observation and qualitative interviews the study argues that the musicians' participation in collectively improvised...... musical practices such as jam session is characterized by the iterative discovery of new action possibilities in pursuing a collectively negotiated 'common third': the good music. The study further argues that the musicians’ perpetually changing participation in the jam practice and the development...... of the improvised music itself are inseparable and interdependant. Learning to jam is argued to be situated in the social practice of jamming, thus prototypically presenting learning to be analyzed as improvised development of practice per se. A discussion of the findings' potential for developing teaching...

  18. Dynamical correlations near dislocation jamming.

    Science.gov (United States)

    Laurson, Lasse; Miguel, M-Carmen; Alava, Mikko J

    2010-07-02

    Dislocation assemblies exhibit a jamming or yielding transition at a critical external shear stress value σ=σ{c}. Here we study the heterogeneous and collective nature of dislocation dynamics within a crystal plasticity model close to σ{c}, by considering the first-passage properties of the dislocation dynamics. As the transition is approached in the moving phase, the first-passage time distribution exhibits scaling, and a related peak dynamical susceptibility χ{4}{*} diverges as χ{4}{*}∼(σ-σ{c}){-α}, with α≈1.1. We relate this scaling to an avalanche description of the dynamics. While the static structural correlations are found to be independent of the external stress, we identify a diverging dynamical correlation length ξ{y} in the direction perpendicular to the dislocation glide motion.

  19. Electromagnetic anti-jam telemetry tool

    Science.gov (United States)

    Ganesan, Harini [Sugar Land, TX; Mayzenberg, Nataliya [Missouri City, TX

    2008-02-12

    A mud-pulse telemetry tool includes a tool housing, a motor disposed in the tool housing, and a magnetic coupling coupled to the motor and having an inner shaft and an outer shaft. The tool may also include a stator coupled to the tool housing, a restrictor disposed proximate the stator and coupled to the magnetic coupling, so that the restrictor and the stator adapted to generate selected pulses in a drilling fluid when the restrictor is selectively rotated. The tool may also include a first anti-jam magnet coupled to the too housing, and an second anti-jam magnet disposed proximate the first anti-jam magnet and coupled to the inner shaft and/or the outer shaft, wherein at least one of the first anti-jam magnet and the second anti-jam magnet is an electromagnet, and wherein the first anti-jam magnet and the second anti-jam magnet are positioned with adjacent like poles.

  20. Furan: A critical heat induced dietary contaminant

    DEFF Research Database (Denmark)

    Mariotti, María S.; Granby, Kit; Rozowski, Jaime

    2013-01-01

    -induced tumor formation, current human exposure levels to this contaminant may indicate a risk to human health and the necessity for its mitigation. This review summarizes and focuses on the main issues of furan toxicity, human dietary exposure to furan and mechanisms of furan formation. Additionally, the role...

  1. Granular jamming transitions for a robotic mechanism

    Science.gov (United States)

    Jiang, Allen; Aste, Tomaso; Dasgupta, Prokar; Althoefer, Kaspar; Nanayakkara, Thrishantha

    2013-06-01

    The jamming transitions for granules growing field of interest in robotics for use in variable stiffness mechanisms. However, the traditional use of air pressure to control the jamming transition requires heavy vacuums, reducing the mobility of the robot. Thus, we propose the use of water as a hydraulic fluid to control the transition between free and clustered granules. This paper presents comparative studies that show that a hydraulic granular jammed finger joint can both achieve the same stiffness level and maintain the same hysteresis level of a pneumatic system, with only a small volume of fluid.

  2. Concept of heat-induced inkless eco-printing.

    Science.gov (United States)

    Chen, Jinxiang; Wang, Yong; Xie, Juan; Meng, Chuang; Wu, Gang; Zu, Qiao

    2012-07-01

    Existing laser and inkjet printers often produce adverse effects on human health, the recycling of printing paper and the environment. Therefore, this paper examines the thermogravimetry curves for printer paper, analyzes the discoloration of paper using heat-induction, and investigates the relationship between paper discoloration and the heat-inducing temperature. The mechanism of heat-induced printing is analyzed initially, and its feasibility is determined by a comparative analysis of heat-induced (laser ablation) printing and commercial printing. The innovative concept of heat-induced inkless eco-printing is proposed, in which the required text or graphics are formed on the printing paper via yellowing and blackening produced by thermal energy. This process does not require ink during the printing process; thus, it completely eliminates the aforementioned health and environmental issues. This research also contributes to related interdisciplinary research in biology, laser technology, photochemistry, nano-science, paper manufacturing and color science. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. Jamming as a Threat to Navigation

    Directory of Open Access Journals (Sweden)

    Świerczyński Sławomir

    2016-12-01

    Full Text Available The whole world is dependent on satellite systems as they are used in almost all fields of economic and social life, in transport, banking, industry, agriculture, etc. Thanks to the development of technology, most smartphones used everyday have been equipped with a built-in GNSS receiver, many cars with navigation systems and all vessels with GNSS receiver or a satellite compass for navigation. Systems working on similar frequencies can be used for jamming or spoofing satellite systems. Such purposeful system jamming can be damaging to users and society as a whole. This article includes a description of jamming and a presentation of one of possible receiver designs allowing for jamming signal detection. This receiver has been designed and built by the authors of the article.

  4. Divergent JAM-C Expression Accelerates Monocyte-Derived Cell Exit from Atherosclerotic Plaques.

    Directory of Open Access Journals (Sweden)

    Paul F Bradfield

    Full Text Available Atherosclerosis, caused in part by monocytes in plaques, continues to be a disease that afflicts the modern world. Whilst significant steps have been made in treating this chronic inflammatory disease, questions remain on how to prevent monocyte and macrophage accumulation in atherosclerotic plaques. Junctional Adhesion Molecule C (JAM-C expressed by vascular endothelium directs monocyte transendothelial migration in a unidirectional manner leading to increased inflammation. Here we show that interfering with JAM-C allows reverse-transendothelial migration of monocyte-derived cells, opening the way back out of the inflamed environment. To study the role of JAM-C in plaque regression we used a mouse model of atherosclerosis, and tested the impact of vascular JAM-C expression levels on monocyte reverse transendothelial migration using human cells. Studies in-vitro under inflammatory conditions revealed that overexpression or gene silencing of JAM-C in human endothelium exposed to flow resulted in higher rates of monocyte reverse-transendothelial migration, similar to antibody blockade. We then transplanted atherosclerotic, plaque-containing aortic arches from hyperlipidemic ApoE-/- mice into wild-type normolipidemic recipient mice. JAM-C blockade in the recipients induced greater emigration of monocyte-derived cells and further diminished the size of atherosclerotic plaques. Our findings have shown that JAM-C forms a one-way vascular barrier for leukocyte transendothelial migration only when present at homeostatic copy numbers. We have also shown that blocking JAM-C can reduce the number of atherogenic monocytes/macrophages in plaques by emigration, providing a novel therapeutic strategy for chronic inflammatory pathologies.

  5. Culture Jamming Versus Popular Culture

    Directory of Open Access Journals (Sweden)

    Leonardia Acynthia Putri

    2013-11-01

    Full Text Available Abstract: This literature study researched Adbusters, the anti-commercial organization, and described the organization’s activities and media usage, mainly in the period of 2007-2010, which critized the populer culture. Adbusters is an organization which performs “Culture Jamming”; a rebellious act reacting towards commercialism domination in many aspects including popular culture. Compared to other similar organizations, Adbusters has been executing more various activisms using several media which other organizations do not use. This study used the Adbusters’ official website and blogs as main data sources. The data of Adbusters’ activities and media usage were categorized and analyzed, thus the tendency of its development can be described. This study also analyzed Adbusters’ activity using Media Hegemony Theory and Political Economy Media Theory. The media has been dominated by a certain group that owns politic and economic power, so the information flow has been dominated by them. Media and its contents have been commercialized, thus capitalism and commercialism have been considered as a common system that should run the world. Adbusters has been trying to stop the domination and change the society’s way of thinking into a more critical way of thinking.   Abstrak: Studi literatur ini meneliti tentang Adbusters, sebuah organisasi anti komersial, dengan mendeskripsikan aktivitas serta penggunaan media organisasi tersebut dari tahun 2007-2010 dalam mengkritisi budaya populer. Adbusters adalah organisasi yang melakukan Culture Jamming, aksi perlawanan terhadap dominasi komersialisme di segala aspek termasuk popular culture. Dibandingkan dengan organisasi lain yang serupa, aktivitas Adbusters lebih bervariasi dan menggunakan media-media yang tidak biasa digunakan organisasi lain. Penelitian ini menggunakan situs online resmi Adbusters sebagai sumber data utama. Data mengenai aktivitas dan

  6. Flow-induced vibration of component cooling water heat exchangers

    Energy Technology Data Exchange (ETDEWEB)

    Yeh, Y.S.; Chen, S.S. (Taiwan Power Co., Taipei (Taiwan). Nuclear Engineering Dept.; Argonne National Lab., IL (USA))

    1990-01-01

    This paper presents an evaluation of flow-induced vibration problems of component cooling water heat exchangers in one of Taipower's nuclear power stations. Specifically, it describes flow-induced vibration phenomena, tests to identify the excitation mechanisms, measurement of response characteristics, analyses to predict tube response and wear, various design alterations, and modifications of the original design. Several unique features associated with the heat exchangers are demonstrated, including energy-trapping modes, existence of tube-support-plate (TSP)-inactive modes, and fluidelastic instability of TSP-active and -inactive modes. On the basis of this evaluation, the difficulties and future research needs for the evaluation of heat exchangers are identified. 11 refs., 19 figs., 3 tabs.

  7. Comparison of Heat-Induced Aggregation of Globular Proteins

    NARCIS (Netherlands)

    Delahaije, R.J.B.M.; Wierenga, P.A.; Giuseppin, M.L.F.; Gruppen, H.

    2015-01-01

    Typically, heat-induced aggregation of proteins is studied using a single protein under various conditions (e.g., temperature). Because different studies use different conditions and methods, a mechanistic relationship between molecular properties and the aggregation behavior of proteins has not

  8. Photo-induced-heat localization on nanostructured metallic glasses

    Science.gov (United States)

    Uzun, Ceren; Kahler, Niloofar; Grave de Peralta, Luis; Kumar, Golden; Bernussi, Ayrton A.

    2017-09-01

    Materials with large photo-thermal energy conversion efficiency are essential for renewable energy applications. Photo-excitation is an effective approach to generate controlled and localized heat at relatively low excitation optical powers. However, lateral heat diffusion to the surrounding illuminated areas accompanied by low photo-thermal energy conversion efficiency remains a challenge for metallic surfaces. Surface nanoengineering has proven to be a successful approach to further absorption and heat generation. Here, we show that pronounced spatial heat localization and high temperatures can be achieved with arrays of amorphous metallic glass nanorods under infrared optical illumination. Thermography measurements revealed marked temperature contrast between illuminated and non-illuminated areas even under low optical power excitation conditions. This attribute allowed for generating legible photo-induced thermal patterns on textured metallic glass surfaces.

  9. Thermal Runaway in Jammed Networks

    Science.gov (United States)

    Lechman, Jeremy; Yarrington, Cole; Bolintineanu, Dan

    2017-06-01

    The study of thermal explosion has a long history. Names such as Semenov and Frank-Kamenetskii are associated with classical model descriptions under particular assumptions. In this talk we revisit this problem with particular focus on the latter's model for conduction dominated thermal transport and Arrenhius-type reaction chemistry. We extend this description to the case of inhomogeneous microstructure generated by packing mono-sized spheres via a well-defined ``Jamming'' protocol. With these material structures in hand, we recast the Frank-Kamenetskii problem into a reduced-order network form for conduction in particle packs. With this model we can efficiently investigate the variability of the time to ignition due to the random microstructure. Additionally, we propose a modal decomposition and stability analysis of the model akin to stability of linear systems. We highlight the physical insights this approach can give with respect to questions of material dependent performance variability. Sandia National Laboratories is a multiprogram laboratory managed and operated by Sandia Corporation, a Lockheed-Martin Company, for the U. S. Department of Energy's National Nuclear Security Administration under Contract No. DE-AC04-94AL85000.

  10. SIFAT KIMIA SELAI BUAH NAGA, KOMPOSISI MIKROFLORA DAN PROFIL SCFA FESES RELAWAN [Chemical Properties of Drugon Fruit Jam, Microflora Composition and SCFA Profile of Human Volunteer Faecal

    Directory of Open Access Journals (Sweden)

    Nurhayati

    2015-12-01

    Full Text Available Dragon fruit contains oligosaccharides, Including prebiotic ingredients, that are namely raffinose, stachyose, and fructo-oligosaccharides. The heat treatment process like jam producing can affect the functional properties of a food material. The aim of the research wereto know the effect of jam processing on chemical properties, and their prebiotic properties. Evaluation of the prebiotic properties was conducted by in vivo method i.e. probiotic and enterobacteria population of volunteers faecal (microflora composition, prebiotic index (PI value and Short Chain Fatty Acid (SCFA profile. The result showed that the processing of dragon fruit into jams decreased water content, β-sianin and dissolved particles but increased the Insoluble Indigestible Fraction (IIF. The PI value of dragon fruit jam were 1.70 for white dragon jam and 1.18 for red dragon fruit. The jam processing decreased PI value up to 0.49 (red dragon fruit jam and 0.54 (white dragon fruit jam. The fresh dragon fruit and the jam produced short chain fatty acid (SCFA i.e. acetic and propionic acid. It can be concluded that prebiotic properties of white dragon fruit better than red dragon fruit.

  11. Systemic analysis of heat shock response induced by heat shock and a proteasome inhibitor MG132.

    Directory of Open Access Journals (Sweden)

    Hee-Jung Kim

    Full Text Available The molecular basis of heat shock response (HSR, a cellular defense mechanism against various stresses, is not well understood. In this, the first comprehensive analysis of gene expression changes in response to heat shock and MG132 (a proteasome inhibitor, both of which are known to induce heat shock proteins (Hsps, we compared the responses of normal mouse fibrosarcoma cell line, RIF-1, and its thermotolerant variant cell line, TR-RIF-1 (TR, to the two stresses. The cellular responses we examined included Hsp expressions, cell viability, total protein synthesis patterns, and accumulation of poly-ubiquitinated proteins. We also compared the mRNA expression profiles and kinetics, in the two cell lines exposed to the two stresses, using microarray analysis. In contrast to RIF-1 cells, TR cells resist heat shock caused changes in cell viability and whole-cell protein synthesis. The patterns of total cellular protein synthesis and accumulation of poly-ubiquitinated proteins in the two cell lines were distinct, depending on the stress and the cell line. Microarray analysis revealed that the gene expression pattern of TR cells was faster and more transient than that of RIF-1 cells, in response to heat shock, while both RIF-1 and TR cells showed similar kinetics of mRNA expression in response to MG132. We also found that 2,208 genes were up-regulated more than 2 fold and could sort them into three groups: 1 genes regulated by both heat shock and MG132, (e.g. chaperones; 2 those regulated only by heat shock (e.g. DNA binding proteins including histones; and 3 those regulated only by MG132 (e.g. innate immunity and defense related molecules. This study shows that heat shock and MG132 share some aspects of HSR signaling pathway, at the same time, inducing distinct stress response signaling pathways, triggered by distinct abnormal proteins.

  12. Early Detection of Junctional Adhesion Molecule-1 (JAM-1 in the Circulation after Experimental and Clinical Polytrauma

    Directory of Open Access Journals (Sweden)

    Stephanie Denk

    2015-01-01

    Full Text Available Severe tissue trauma-induced systemic inflammation is often accompanied by evident or occult blood-organ barrier dysfunctions, frequently leading to multiple organ dysfunction. However, it is unknown whether specific barrier molecules are shed into the circulation early after trauma as potential indicators of an initial barrier dysfunction. The release of the barrier molecule junctional adhesion molecule-1 (JAM-1 was investigated in plasma of C57BL/6 mice 2 h after experimental mono- and polytrauma as well as in polytrauma patients (ISS ≥ 18 during a 10-day period. Correlation analyses were performed to indicate a linkage between JAM-1 plasma concentrations and organ failure. JAM-1 was systemically detected after experimental trauma in mice with blunt chest trauma as a driving force. Accordingly, JAM-1 was reduced in lung tissue after pulmonary contusion and JAM-1 plasma levels significantly correlated with increased protein levels in the bronchoalveolar lavage as a sign for alveolocapillary barrier dysfunction. Furthermore, JAM-1 was markedly released into the plasma of polytrauma patients as early as 4 h after the trauma insult and significantly correlated with severity of disease and organ dysfunction (APACHE II and SOFA score. The data support an early injury- and time-dependent appearance of the barrier molecule JAM-1 in the circulation indicative of a commencing trauma-induced barrier dysfunction.

  13. Impact of Ridge Induced Latent Heat Advection on Sea Ice Global Heat Budget.

    Science.gov (United States)

    Hudier, E.; Gosselin, J.

    2008-12-01

    The effects of permeability on ice keel induced latent heat fluxes are examined using pressure ridge density statistics computed from SAR images and a prognostic simulation of forced brine advection through the bottom ice layer. Under pressure gradients generated in the wake of an ice keel sea water is pushed into and brine pumped out of the bottom ice layer. This in turn causes a new thermodynamic equilibrium to be reached. At spring when the ice permeability increases, brine export combined with sea water import translates into an advective heat flow that is balanced by the latent heat absorbed by volume melting of brine channel walls. Sea ice within the sheltered areas behind keels is modelled as an anisotropic heteregeneous mushy layer. The non-linear equation system within each cell is implemented on a finite volume grid and include volume melt of the brine channels from which porosity, water density, temperature and salinity are computed. Outputs from these simulations are then combined with ridge distribution statistics to evaluate the global impact of latent heat absorbed due to volume melting in the wake of ridges. As anticipated, results are highly dependent on permeability, nevertheless, they show that pressure ridge induced melting within the ice is a significant component of the heat budget when compared with melting at the ice water interface. This work underlines needs for further researches to improve our understanding of ice permeability changes during the melt season, it also calls for better tools to extract pressure ridge characteristics from satellite images.

  14. Penetrative convective flows induced by internal heating and mantle compressibility

    Science.gov (United States)

    Machetel, Philippe; Yuen, David A.

    1989-01-01

    Penetrative convective flows induced in a spherical shell by combined effects of internal heating and mantle compressibility are investigated using mathematical and numerical formulations for compressible spherical shell convection. Isothermal stress-free boundary conditions applied at the top and the bottom of the shell are solved using a time-dependent finite difference code in a temperature, vorticity, stream function formulation for Rayleigh numbers ranging from the critical Rc up to 2000 Rc. Results indicate that compressibility, together with internal heating, could be a mechanism capable of generating spontaneously layered convection and local melting in the mantle and that non-Boussinesq effects must be considered in interpretations of geophysical phenomena.

  15. Enhanced heat sink with geometry induced wall-jet

    Energy Technology Data Exchange (ETDEWEB)

    Hossain, Md. Mahamudul, E-mail: sohel0991@gmail.com; Tikadar, Amitav; Bari, Fazlul; Morshed, A. K. M. M. [Department of Mechanical Engineering Bangladesh University of Engineering and Technology, Dhaka-1000. Bangladesh (Bangladesh)

    2016-07-12

    Mini-channels embedded in solid matrix have already proven to be a very efficient way of electronic cooling. Traditional mini-channel heat sinks consist of single layer of parallel channels. Although mini-channel heat sink can achieve very high heat flux, its pumping requirement for circulating liquid through the channel increase very sharply as the flow velocity increases. The pumping requirements of the heat sink can be reduced by increasing its performance. In this paper a novel approach to increase the thermal performance of the mini-channel heat sink is proposed through geometry induced wall jet which is a passive technique. Geometric irregularities along the channel length causes abrupt pressure change between the channels which causes cross flow through the interconnections thus one channel faces suction and other channel jet action. This suction and jet action disrupts boundary layer causing enhanced heat transfer performance. A CFD model has been developed using commercially available software package FLUENT to evaluate the technique. A parametric study of the velocities and the effect of the position of the wall-jets have been performed. Significant reduction in thermal resistance has been observed for wall-jets, it is also observed that this reduction in thermal resistance is dependent on the position and shape of the wall jet.

  16. Heterogeneous nuclear ribonucleoprotein K inhibits heat shock-induced transcriptional activity of heat shock factor 1.

    Science.gov (United States)

    Kim, Hee-Jung; Lee, Jae-Jin; Cho, Jin-Hwan; Jeong, Jaeho; Park, A Young; Kang, Wonmo; Lee, Kong-Joo

    2017-08-04

    When cells are exposed to heat shock and various other stresses, heat shock factor 1 (HSF1) is activated, and the heat shock response (HSR) is elicited. To better understand the molecular regulation of the HSR, we used 2D-PAGE-based proteome analysis to screen for heat shock-induced post-translationally modified cellular proteins. Our analysis revealed that two protein spots typically present on 2D-PAGE gels and containing heterogeneous nuclear ribonucleoprotein K (hnRNP K) with trioxidized Cys132 disappeared after the heat shock treatment and reappeared during recovery, but the total amount of hnRNP K protein remained unchanged. We next tested whether hnRNP K plays a role in HSR by regulating HSF1 and found that hnRNP K inhibits HSF1 activity, resulting in reduced expression of hsp70 and hsp27 mRNAs. hnRNP K also reduced binding affinity of HSF1 to the heat shock element by directly interacting with HSF1 but did not affect HSF1 phosphorylation-dependent activation or nuclear localization. hnRNP K lost its ability to induce these effects when its Cys132 was substituted with Ser, Asp, or Glu. These findings suggest that hnRNP K inhibits transcriptional activity of HSF1 by inhibiting its binding to heat shock element and that the oxidation status of Cys132 in hnRNP K is critical for this inhibition. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  17. Jamming and liquidity in 3D cancer cell aggregates

    Science.gov (United States)

    Oswald, Linda; Grosser, Steffen; Lippoldt, Jürgen; Pawlizak, Steve; Fritsch, Anatol; KäS, Josef A.

    Traditionally, tissues are treated as simple liquids, which holds for example for embryonic tissue. However, recent experiments have shown that this picture is insufficient for other tissue types, suggesting possible transitions to solid-like behavior induced by cellular jamming. The coarse-grained self-propelled Voronoi (SPV) model predicts such a transition depending on cell shape which is thought to arise from an interplay of cell-cell adhesion and cortical tension. We observe non-liquid behavior in 3D breast cancer spheroids of varying metastatic potential and correlate single cell shapes, single cell dynamics and collective dynamic behavior of fusion and segregation experiments via the SPV model.

  18. Platform skin return and retrodirective cross-eye jamming

    CSIR Research Space (South Africa)

    Du Plessis, WP

    2012-01-01

    Full Text Available antenna separation must be as large as possible because the induced error is a function of the jammer antenna spacing [6]?[8]. Given that cross-eye jamming originated as an attempt to recreate glint, it is not surprising that one of the earliest glint... (2k) is not close to -1 ensuring that the denominator of (22) is not small), and 3) the sum-channel jammer return and the sum-channel skin return do not cancel (1 + aej? + asej?s is not small enough to violate the relationship in (22)). Conditions...

  19. Viscoelastic response near the jamming transition

    Science.gov (United States)

    Tighe, Brian

    2011-03-01

    We use numerical and theoretical methods to investigate oscillatory rheology in soft sphere packings, which serve as a minimal model for foams, emulsions, and other complex fluids that undergo a jamming transition. Although the zero frequency (elastic) properties of jammed media are well documented, far less is known about their viscoelastic response. We demonstrate that the frequency-dependent storage and loss moduli display critical scaling with distance to the jamming point. This behavior is governed by a diverging time scale that separates quasistatic response from a critical regime in which viscous and elastic forces contribute equally to the stress. We provide scaling arguments for all of the relevant critical exponents. Supported by the Dutch Organization for Scientific Research.

  20. Unifying Suspension and Granular flows near Jamming

    Directory of Open Access Journals (Sweden)

    DeGiuli Eric

    2017-01-01

    Full Text Available Rheological properties of dense flows of hard particles are singular as one approaches the jamming threshold where flow ceases, both for granular flows dominated by inertia, and for over-damped suspensions. Concomitantly, the lengthscale characterizing velocity correlations appears to diverge at jamming. Here we review a theoretical framework that gives a scaling description of stationary flows of frictionless particles. Our analysis applies both to suspensions and inertial flows of hard particles. We report numerical results in support of the theory, and show the phase diagram that results when friction is added, delineating the regime of validity of the frictionless theory.

  1. Racemization of Valine by Impact-Induced Heating

    Science.gov (United States)

    Furukawa, Yoshihiro; Takase, Atsushi; Sekine, Toshimori; Kakegawa, Takeshi; Kobayashi, Takamichi

    2017-05-01

    Homochirality plays an important role in all living organisms but its origin remains unclear. It also remains unclear whether such chiral molecules survived terrestrial heavy impact events. Impacts of extraterrestrial objects on early oceans were frequent and could have affected the chirality of oceanic amino acids when such amino acids accumulated during impacts. This study investigated the effects of shock-induced heating on enantiomeric change of valine with minerals such as olivine ([Mg0.9, Fe0.1]2SiO4), hematite (Fe2O3), and calcite (CaCO3). With a shock wave generated by an impact at 0.8 km/s, both uc(d)- and uc(l)-enriched valine were significantly decomposed and partially racemized under all experimental conditions. Different minerals had different shock impedances; therefore, they provided different P-T conditions for identical impacts. Furthermore, the high pH of calcite promoted the racemization of valine. The results indicate that in natural hypervelocity impacts, amino acids in shocked oceanic water would have decomposed completely, since impact velocity and the duration of shock compression and heating are typically greater in hypervelocity impact events than those in experiments. Even with the shock wave by the impact of small and decelerated projectiles in which amino acids survive, the shock heating may generate sufficient heat for significant racemization in shocked oceanic water. However, the duration of shock induced heating by small projectiles is limited and the population of such decelerated projectiles would be limited. Therefore, even though impacts of asteroids and meteorites were frequent on the prebiotic Earth, impact events would not have significantly changed the ee of proteinogenic amino acids accumulated in the entire ocean.

  2. Capacity and coding in the presence of fading and jamming

    Science.gov (United States)

    Stark, W. E.; McEliece, R. J.

    The capacity of noncoherent FSK in the presence of fading and partial band jamming is presented. It is observed that for both partial band jamming and fading there is an optimal nonzero code rate that minimizes the energy per bit required to achieve reliable communication. For low enough code rates uniform jamming is the best strategy that the jammer can adopt. We also give results for Reed-Solomon codes on the partial-band jamming channel.

  3. Production and Evaluation of Jam from Roselle Calyx Extract | Mordi ...

    African Journals Online (AJOL)

    The aqueous extract of Roselle calyx was processed into jam by washing the calyx, extraction by boiling in hot water, filtration, formulation using the filtrate, boiling, filling into glass bottles and pasteurization. The physicochemical properties and nutritional composition of the jam were analyzed. The resulting jam had pH 2.90 ...

  4. Nutrient and Anti nutrient Composition of Jams Prepared from ...

    African Journals Online (AJOL)

    The nutrient composition of prepared jams was higher than that of commercially available (control) one, though commercial jam rated highest in all sensory parameters investigated. Addition of carrot extract improved the â-carotene content and acceptability of prepared jams. Conclusion: The relatively high level of -carotene ...

  5. Jamón jamón (1992): De jamones y cuernos

    OpenAIRE

    Sanabria, Carolina

    2013-01-01

    Entrados los años 90 y tras una recién inaugurada carrera cinematográfica que le merecería premios y buenas críticas, el director Bigas Luna rodó unatrilogía llamada ibérica, compuesta por Jamón jamón (1992), Huevos de oro (1993) y La teta y la luna (1994). Jamón jamón, la que lo catapultó a la fama, es una historia de relaciones complejas entre personajes diferentes pero marcados por instintos pulsionales que determinan el curso de sus vidas. El artículo pretende analizar desde una perspecti...

  6. Loop Heat Pipe Temperature Oscillation Induced by Gravity Assist and Reservoir Heating

    Science.gov (United States)

    Ku, Jentung; Garrison, Matt; Patel, Deepak; Robinson, Frank; Ottenstein, Laura

    2015-01-01

    The Laser Thermal Control System (LCTS) for the Advanced Topographic Laser Altimeter System (ATLAS) to be installed on NASA's Ice, Cloud, and Land Elevation Satellite (ICESat-2) consists of a constant conductance heat pipe and a loop heat pipe (LHP) with an associated radiator. During the recent thermal vacuum testing of the LTCS where the LHP condenser/radiator was placed in a vertical position above the evaporator and reservoir, it was found that the LHP reservoir control heater power requirement was much higher than the analytical model had predicted. Even with the control heater turned on continuously at its full power, the reservoir could not be maintained at its desired set point temperature. An investigation of the LHP behaviors found that the root cause of the problem was fluid flow and reservoir temperature oscillations, which led to persistent alternate forward and reversed flow along the liquid line and an imbalance between the vapor mass flow rate in the vapor line and liquid mass flow rate in the liquid line. The flow and temperature oscillations were caused by an interaction between gravity and reservoir heating, and were exacerbated by the large thermal mass of the instrument simulator which modulated the net heat load to the evaporator, and the vertical radiator/condenser which induced a variable gravitational pressure head. Furthermore, causes and effects of the contributing factors to flow and temperature oscillations intermingled.

  7. Analytical Evaluation of Jamming Transition Problem

    DEFF Research Database (Denmark)

    Ganji, S.S; Barari, Amin; Najafi, M.

    2011-01-01

    This paper applies two powerful analytical approximation methods to the jamming transition problem (JTP) of traffic flow networks. The governing equations are modeled on the Lorentz system and take the form of a nonlinear nonconservative oscillator. We describe and implement the homotopy perturba...

  8. Orienterend onderzoek naar het gehalte aan S02 in bosbessen, bramen en frambozen extra jam en -jam

    NARCIS (Netherlands)

    Worp, van der H.; Hollman, P.

    1981-01-01

    Aanleiding tot dit onderzoek is de discussie in de Sub-Commissie Warenwet - jam en limonade over het maximum gehalte aan S02 in jam. Het gevolg hiervan is, dat VKA ons vroeg een oriënterend onderzoek te doen en wel speciaal voor jam van de soorten bosbessen, bramen en frambozen. Inkoop in 5

  9. Fluid-induced rupture on heat-treated andesite

    Science.gov (United States)

    Li, Zhi; Nicolas, Aurelien; Fortin, Jerome; Gueguen, Yves

    2017-04-01

    The aim of this study is to investigate the mechanical behavior, the acoustic emissions (AE) and the evolution ofultrasonic wave velocities during the deformation and failure of andesite samples induced by fluid injection under triaxial stresses. The cylindrical specimens employed in these experiments are andesite samples from Guadeloupe (Geotreff project) (40mm in diameter and 80mm in length). Intact samples have a porosity of 2% and a very low permeability of 10-21 m2. Thus, samples were heat-treated to induce a pre-existing crack network. Different heat treatments were tested (from 200°C et 900°C). Our result show that a minimum heat-treatment of 800°C was necessary to induced a connected crack network (crack density of 0.1), associated with an increase in permeability (10-17 m2). In the following, mechanical experiments were performed on samples heat-treated at 930°C. Mechanical experiments were performed in a conventional triaxial cell (installed at ENS). Four axial strain gauges and four radial strain gauges were glued on the surface of the sample to measure the axial and the radial strain while 16 ultrasonic sensors were glued to measure the ultrasonic velocity and record the acoustic emission activity. A first set of triaxial experiments were performed in order to get the Mohr-Coulomb envelop. Then, the fluid-induced rupture experiment were done as follow: The sample was first saturated under 5MPa confining pressure with 2MPa fluid pressure, then the hydrostatic loading was increased up to 40MPa, followed by an increase in the differential loading to a value close to the dilation point. The sample was maintained under this stress state for 12 hours to make sure there was no creep. Finally, pore fluid was injected from the bottom of the sample at 35MPa and the fluid pressure at the top of the sample was measured (fluid could not escape at the top). Our results show that rupture occurs 1 hour after the fluid injection. A clear sequence of P wave velocity

  10. Rotation-induced deep crustal heating of millisecond pulsars

    Science.gov (United States)

    Gusakov, M. E.; Kantor, E. M.; Reisenegger, A.

    2015-10-01

    The spin-down of a neutron star, e.g. due to magneto-dipole losses, results in compression of the stellar matter and induces nuclear reactions at phase transitions between different nuclear species in the crust. We show that this mechanism is effective in heating recycled pulsars, in which the previous accretion process has already been compressing the crust, so it is not in nuclear equilibrium. We calculate the corresponding emissivity and confront it with available observations, showing that it might account for the likely thermal ultraviolet emission of PSR J0437-4715.

  11. Comparison of heat-induced aggregation of globular proteins.

    Science.gov (United States)

    Delahaije, Roy J B M; Wierenga, Peter A; Giuseppin, Marco L F; Gruppen, Harry

    2015-06-03

    Typically, heat-induced aggregation of proteins is studied using a single protein under various conditions (e.g., temperature). Because different studies use different conditions and methods, a mechanistic relationship between molecular properties and the aggregation behavior of proteins has not been identified. Therefore, this study investigates the kinetics of heat-induced aggregation and the size/density of formed aggregates for three different proteins (ovalbumin, β-lactoglobulin, and patatin) under various conditions (pH, ionic strength, concentration, and temperature). The aggregation rate of β-lactoglobulin was slower (>10 times) than that of ovalbumin and patatin. Moreover, the conditions (pH, ionic strength, and concentration) affected the aggregation kinetics of β-lactoglobulin more strongly than for ovalbumin and patatin. In contrast to the kinetics, for all proteins the aggregate size/density increased with decreasing electrostatic repulsion. By comparing these proteins under these conditions, it became clear that the aggregation behavior cannot easily be correlated to the molecular properties (e.g., charge and exposed hydrophobicity).

  12. Skeletal muscle volume following dehydration induced by exercise in heat.

    Science.gov (United States)

    Hackney, Kyle J; Cook, Summer B; Fairchild, Timothy J; Ploutz-Snyder, Lori L

    2012-09-04

    Intracellular skeletal muscle water is redistributed into the extracellular compartment during periods of dehydration, suggesting an associated decline in muscle volume. The purpose of this study was to evaluate skeletal muscle volume in active (knee extensors (KE)) and less active (biceps/triceps brachii, deltoid) musculature following dehydration induced by exercise in heat. Twelve participants (seven men, five women) cycled in the heat under two conditions: (1) dehydration (DHYD) resulting in 3% and 5% losses of estimated total body water (ETBW), which was assessed by changes in body mass, and (2) fluid replacement (FR) where 3% and 5% losses of ETBW were counteracted by intermittent (20 to 30 min) fluid ingestion via a carbohydrate-electrolyte beverage. During both conditions, serum osmolality and skeletal muscle volume (assessed by magnetic resonance imaging) were measured at baseline and at the 3% and 5% ETBW loss measurement points. In DHYD, serum osmolality increased at 3% (p = 0.005) and 5% (p FR decreased serum osmolality at the 5% loss of ETBW time point (p = 0.009). In DHYD, KE muscle volume declined from 1,464 ± 446 ml to 1,406 ± 425 ml (3.9%, p FR prevented the loss of KE muscle volume at 3% (1,430 ± 435 ml, p = 0.074) and 5% (1,431 ± 439 ml, p = 0.156) ETBW loss time points compared to baseline (1,445 ± 436 ml). Following exercise in the heat, the actively contracting muscles lost volume, while replacing lost fluids intermittently during exercise in heat prevented this decline. These results support the use of muscle volume as a marker of water loss.

  13. Multifrequency OFDM SAR in Presence of Deception Jamming

    Directory of Open Access Journals (Sweden)

    Schuerger Jonathan

    2010-01-01

    Full Text Available Orthogonal frequency division multiplexing (OFDM is considered in this paper from the perspective of usage in imaging radar scenarios with deception jamming. OFDM radar signals are inherently multifrequency waveforms, composed of a number of subbands which are orthogonal to each other. While being employed extensively in communications, OFDM has not found comparatively wide use in radar, and, particularly, in synthetic aperture radar (SAR applications. In this paper, we aim to show the advantages of OFDM-coded radar signals with random subband composition when used in deception jamming scenarios. Two approaches to create a radar signal by the jammer are considered: instantaneous frequency (IF estimator and digital-RF-memory- (DRFM- based reproducer. In both cases, the jammer aims to create a copy of a valid target image via resending the radar signal at prescribed time intervals. Jammer signals are derived and used in SAR simulations with three types of signal models: OFDM, linear frequency modulated (LFM, and frequency-hopped (FH. Presented results include simulated peak side lobe (PSL and peak cross-correlation values for random OFDM signals, as well as simulated SAR imagery with IF and DRFM jammers'-induced false targets.

  14. Multifrequency OFDM SAR in Presence of Deception Jamming

    Science.gov (United States)

    Schuerger, Jonathan; Garmatyuk, Dmitriy

    2010-12-01

    Orthogonal frequency division multiplexing (OFDM) is considered in this paper from the perspective of usage in imaging radar scenarios with deception jamming. OFDM radar signals are inherently multifrequency waveforms, composed of a number of subbands which are orthogonal to each other. While being employed extensively in communications, OFDM has not found comparatively wide use in radar, and, particularly, in synthetic aperture radar (SAR) applications. In this paper, we aim to show the advantages of OFDM-coded radar signals with random subband composition when used in deception jamming scenarios. Two approaches to create a radar signal by the jammer are considered: instantaneous frequency (IF) estimator and digital-RF-memory- (DRFM-) based reproducer. In both cases, the jammer aims to create a copy of a valid target image via resending the radar signal at prescribed time intervals. Jammer signals are derived and used in SAR simulations with three types of signal models: OFDM, linear frequency modulated (LFM), and frequency-hopped (FH). Presented results include simulated peak side lobe (PSL) and peak cross-correlation values for random OFDM signals, as well as simulated SAR imagery with IF and DRFM jammers'-induced false targets.

  15. Triangle and GA Methods for UAVs Jamming

    Directory of Open Access Journals (Sweden)

    Yu Zhang

    2014-01-01

    Full Text Available We focus on how to jam UAVs network efficiently. The system model is described and the problem is formulated. Based on two properties and a theorem which helps to decide good location for a jammer, we present the Triangle method to find good locations for jammers. The Triangle method is easy to understand and has overall computational complexity of ON2. We also present a genetic algorithm- (GA- based jamming method, which has computational complex of OLMN2. New chromosome, mutation, and crossover operations are redefined for the GA method. The simulation shows that Triangle and GA methods perform better than Random method. If the ratio of jammers’ number to UAVs’ number is low (lower than 1/5 in this paper, GA method does better than Triangle method. Otherwise, Triangle method performs better.

  16. Dynamic criticality at the jamming transition.

    Science.gov (United States)

    Ikeda, Atsushi; Berthier, Ludovic; Biroli, Giulio

    2013-03-28

    We characterize vibrational motion occurring at low temperatures in dense suspensions of soft repulsive spheres over a broad range of volume fractions encompassing the jamming transition at (T = 0, ϕ = ϕJ). We find that characteristic time and length scales of thermal vibrations obey critical scaling in the vicinity of the jamming transition. We show in particular that the amplitude and the time scale of dynamic fluctuations diverge symmetrically on both sides of the transition, and directly reveal a diverging correlation length. The critical region near ϕJ is divided in three different regimes separated by a characteristic temperature scale T(⋆)(ϕ) that vanishes quadratically with the distance to ϕJ. While two of them, (T ϕJ) and (T T(⋆)(ϕ) is inherently anharmonic and displays new critical properties. We find that the quadratic scaling of T(⋆)(ϕ) is due to nonperturbative anharmonic contributions, its amplitude being orders of magnitude smaller than the perturbative prediction based on the expansion to quartic order in the interactions. Our results show that thermal vibrations in colloidal assemblies directly reveal the critical nature of the jamming transition. The critical region, however, is very narrow and has not yet been attained experimentally, even in recent specifically-dedicated experiments.

  17. Heat stress induces ferroptosis-like cell death in plants.

    Science.gov (United States)

    Distéfano, Ayelén Mariana; Martin, María Victoria; Córdoba, Juan Pablo; Bellido, Andrés Martín; D'Ippólito, Sebastián; Colman, Silvana Lorena; Soto, Débora; Roldán, Juan Alfredo; Bartoli, Carlos Guillermo; Zabaleta, Eduardo Julián; Fiol, Diego Fernando; Stockwell, Brent R; Dixon, Scott J; Pagnussat, Gabriela Carolina

    2017-02-01

    In plants, regulated cell death (RCD) plays critical roles during development and is essential for plant-specific responses to abiotic and biotic stresses. Ferroptosis is an iron-dependent, oxidative, nonapoptotic form of cell death recently described in animal cells. In animal cells, this process can be triggered by depletion of glutathione (GSH) and accumulation of lipid reactive oxygen species (ROS). We investigated whether a similar process could be relevant to cell death in plants. Remarkably, heat shock (HS)-induced RCD, but not reproductive or vascular development, was found to involve a ferroptosis-like cell death process. In root cells, HS triggered an iron-dependent cell death pathway that was characterized by depletion of GSH and ascorbic acid and accumulation of cytosolic and lipid ROS. These results suggest a physiological role for this lethal pathway in response to heat stress in Arabidopsis thaliana The similarity of ferroptosis in animal cells and ferroptosis-like death in plants suggests that oxidative, iron-dependent cell death programs may be evolutionarily ancient. © 2017 Distéfano et al.

  18. Granular drag and the kinetics of jamming

    Science.gov (United States)

    Brzinski, Theodore A., III

    The first part of this thesis focuses on the study of the force exerted by a granular packing on an intruder. During impact, this force can be described by the linear combination of an inertial drag and a rate-independent frictional force that is proportional to depth. We measure the torque acting on a rod rotated perpendicular to its axis in a granular bed at steady state, and demonstrate that the resisting force is of the same form, though smaller. We then alter the hydrostatic loading on the bed by generating a homogenized airflow through the bed, and show that for horizontal motion the frictional force is due to friction acting at gravity-loaded contacts. Next we directly measure the force acting on quasistatically, vertically lowered intruders under two sets of varied conditions. First we vary the shape of the projectile in order to alter the fraction of the projectile surface that moves parallel vs perpendicular to the medium, and find that the frictional force acts primarily normal to the intruder surface. Second, we alter the hydrostatic loading as above, and confirm that gravity-loading of the grains sets the magnitude of the resisting force for quasi-static vertical motion as well. Finally, we consider the case of impact onto wet grains. We conduct conventional impact experiments wherein a spherical projectile impacts onto a granular packing with a known impact speed. We vary the liquid, impact speed, and degree of saturation, and find that the penetration depth is decreased for all wetting fractions, and that the penetration depth has a non-monotonic dependence on liquid saturation. In the fully saturated case, we recover the same scaling of penetration depth with geometry, impact speed and packing density as in the dry case, though the penetrations are shallower, suggesting a hydrodynamic contribution to the net stopping force. The second part of this thesis focuses on the kinetics of the jamming transition. In particular, we observe a dispersion of

  19. Mango (Mangifera Indica) Jam Production Technology

    OpenAIRE

    Mandey, Lucia C; Mamuaja, Christine F

    2016-01-01

    Mango fuit jam is a semi-wet food products made of mango pulp processing and sucrose with or without the addition of permitted food additives. Mango fruit as other horticultural products is a food that can be easily damaged or rotten. In the harvest season mango production is very plentiful and many are not consumed, as a result, mango fruit becomes spoiled. The total spoiled mangoes can reach 35%, due to the perishable nature of this fruit cause losses to farmers and fruit sellers. The gre...

  20. Molecular dynamics simulation of ribosome jam

    KAUST Repository

    Matsumoto, Shigenori

    2011-09-01

    We propose a coarse-grained molecular dynamics model of ribosome molecules to study the dependence of translation process on environmental parameters. We found the model exhibits traffic jam property, which is consistent with an ASEP model. We estimated the influence of the temperature and concentration of molecules on the hopping probability used in the ASEP model. Our model can also treat environmental effects on the translation process that cannot be explained by such cellular automaton models. © 2010 Elsevier B.V. All rights reserved.

  1. Heat shock transcription factors regulate heat induced cell death in a ...

    Indian Academy of Sciences (India)

    2007-03-29

    Hsps) which is strictly regulated by different members of heat shock transcription factors (HSFs). We previously reported that a rat histiocytoma, BC-8 failed to synthesize Hsps when subjected to typical heat shock conditions (42°C, ...

  2. Nature of transition from jamming to creep and dense flow in granular heaps

    Science.gov (United States)

    Ortiz, C. P.; Ferdowsi, B.; Jerolmack, D. J.

    2016-12-01

    A first-principles understanding of the geomorphology of hillslopes and river beds depends on understanding how granular materials flow over long times. A fundamental tenet of sediment transport models is the critical stress for the onset of particle motion, below which particles are static. The latter corresponds to the "jammed" state in granular materials, and understanding the transition from jammed to flowing for disordered granular systems remains a frontier research area. Yet, jamming is not the whole story; granular materials flow slowly at stresses below critical - i.e., they can be mechanically unstable where we expect them to be stable. This creeping behavior is well known for hillslopes, and recent experiments show it is also relevant for river systems. Multiple mechanisms to explain creep have been advanced, but the transition from jammed to creeping is mostly unexplored. Moreover, geological explanations for creep revolve around an effective reduction in material friction due to dilation induced by external perturbations; however, this is incompatible with the picture of creep arising out of granular physics studies. Because of the experimental challenges involved in measuring exceedingly slow particle motion, we use numerical simulations to probe the jammed to creeping transition. We prepare initially static heaps of grains with frictional interactions, and study their response to force and velocity perturbations at the scale of single particles. We examine the relaxation process of the structure back to a jammed state in the long-time limit by characterizing velocity, free-volume, and the size of force-clusters over time. By comparing the response function to the structural evolution, we identify the properties of the perturbations that allow packs to escape from the initial mechanically stable state, allowing us to develop a microscopic picture for the transition from jamming to creep. Our results help to understand the origins of granular creep

  3. Effects of propofol on damage of rat intestinal epithelial cells induced by heat stress and lipopolysaccharides

    Energy Technology Data Exchange (ETDEWEB)

    Tang, J.; Jiang, Y. [Southern Medical University, Nanfang Hospital, Department of Anesthesia, Guangzhou, China, Department of Anesthesia, Nanfang Hospital, Southern Medical University, Guangzhou (China); Tang, Y.; Chen, B. [Guangzhou General Hospital of Guangzhou Military Command, Department of Intensive Care Unit, Guangzhou, China, Department of Intensive Care Unit, Guangzhou General Hospital of Guangzhou Military Command, Guangzhou (China); Sun, X. [Laboratory of Traditional Chinese Medicine Syndrome, School of Traditional Chinese Medicine, Southern Medical University, Guangzhou (China); Su, L.; Liu, Z. [Guangzhou General Hospital of Guangzhou Military Command, Department of Intensive Care Unit, Guangzhou, China, Department of Intensive Care Unit, Guangzhou General Hospital of Guangzhou Military Command, Guangzhou (China)

    2013-06-25

    Gut-derived endotoxin and pathogenic bacteria have been proposed as important causative factors of morbidity and death during heat stroke. However, it is still unclear what kind of damage is induced by heat stress. In this study, the rat intestinal epithelial cell line (IEC-6) was treated with heat stress or a combination of heat stress and lipopolysaccharide (LPS). In addition, propofol, which plays an important role in anti-inflammation and organ protection, was applied to study its effects on cellular viability and apoptosis. Heat stress, LPS, or heat stress combined with LPS stimulation can all cause intestinal epithelial cell damage, including early apoptosis and subsequent necrosis. However, propofol can alleviate injuries caused by heat stress, LPS, or the combination of heat stress and LPS. Interestingly, propofol can only mitigate LPS-induced intestinal epithelial cell apoptosis, and has no protective role in heat-stress-induced apoptosis. This study developed a model that can mimic the intestinal heat stress environment. It demonstrates the effects on intestinal epithelial cell damage, and indicated that propofol could be used as a therapeutic drug for the treatment of heat-stress-induced intestinal injuries.

  4. River predisposition to ice jams: a simplified geospatial model

    Science.gov (United States)

    De Munck, Stéphane; Gauthier, Yves; Bernier, Monique; Chokmani, Karem; Légaré, Serge

    2017-07-01

    Floods resulting from river ice jams pose a great risk to many riverside municipalities in Canada. The location of an ice jam is mainly influenced by channel morphology. The goal of this work was therefore to develop a simplified geospatial model to estimate the predisposition of a river channel to ice jams. Rather than predicting the timing of river ice breakup, the main question here was to predict where the broken ice is susceptible to jam based on the river's geomorphological characteristics. Thus, six parameters referred to potential causes for ice jams in the literature were initially selected: presence of an island, narrowing of the channel, high sinuosity, presence of a bridge, confluence of rivers, and slope break. A GIS-based tool was used to generate the aforementioned factors over regular-spaced segments along the entire channel using available geospatial data. An ice jam predisposition index (IJPI) was calculated by combining the weighted optimal factors. Three Canadian rivers (province of Québec) were chosen as test sites. The resulting maps were assessed from historical observations and local knowledge. Results show that 77 % of the observed ice jam sites on record occurred in river sections that the model considered as having high or medium predisposition. This leaves 23 % of false negative errors (missed occurrence). Between 7 and 11 % of the highly predisposed river sections did not have an ice jam on record (false-positive cases). Results, limitations, and potential improvements are discussed.

  5. Intelligent cognitive radio jamming - a game-theoretical approach

    Science.gov (United States)

    Dabcevic, Kresimir; Betancourt, Alejandro; Marcenaro, Lucio; Regazzoni, Carlo S.

    2014-12-01

    Cognitive radio (CR) promises to be a solution for the spectrum underutilization problems. However, security issues pertaining to cognitive radio technology are still an understudied topic. One of the prevailing such issues are intelligent radio frequency (RF) jamming attacks, where adversaries are able to exploit on-the-fly reconfigurability potentials and learning mechanisms of cognitive radios in order to devise and deploy advanced jamming tactics. In this paper, we use a game-theoretical approach to analyze jamming/anti-jamming behavior between cognitive radio systems. A non-zero-sum game with incomplete information on an opponent's strategy and payoff is modelled as an extension of Markov decision process (MDP). Learning algorithms based on adaptive payoff play and fictitious play are considered. A combination of frequency hopping and power alteration is deployed as an anti-jamming scheme. A real-life software-defined radio (SDR) platform is used in order to perform measurements useful for quantifying the jamming impacts, as well as to infer relevant hardware-related properties. Results of these measurements are then used as parameters for the modelled jamming/anti-jamming game and are compared to the Nash equilibrium of the game. Simulation results indicate, among other, the benefit provided to the jammer when it is employed with the spectrum sensing algorithm in proactive frequency hopping and power alteration schemes.

  6. Jamming and Learning: Analysing Changing Collective Practice of Changing Participation

    Science.gov (United States)

    Brinck, Lars

    2017-01-01

    This article reports a long-term ethnographic study on jamming and learning from an entwined artistic and educational perspective. The study investigates aspects of learning during a professional band's jamming and recording eight groove-jazz frameworks and a series of subsequent concerts with pre-academy students "sitting in." Fieldwork…

  7. Physico-chemical properties and sensory evaluation of jam made ...

    African Journals Online (AJOL)

    This study was carried out to investigate the possibility of producing jam from black-plum and to evaluate the physico-chemical properties, nutritional properties and consumer acceptability of the product. Black-plum jam was produced using traditional openkettle method. The physico-chemical analyses of black-plum fruit ...

  8. River predisposition to ice jams: a simplified geospatial model

    Directory of Open Access Journals (Sweden)

    S. De Munck

    2017-07-01

    Full Text Available Floods resulting from river ice jams pose a great risk to many riverside municipalities in Canada. The location of an ice jam is mainly influenced by channel morphology. The goal of this work was therefore to develop a simplified geospatial model to estimate the predisposition of a river channel to ice jams. Rather than predicting the timing of river ice breakup, the main question here was to predict where the broken ice is susceptible to jam based on the river's geomorphological characteristics. Thus, six parameters referred to potential causes for ice jams in the literature were initially selected: presence of an island, narrowing of the channel, high sinuosity, presence of a bridge, confluence of rivers, and slope break. A GIS-based tool was used to generate the aforementioned factors over regular-spaced segments along the entire channel using available geospatial data. An ice jam predisposition index (IJPI was calculated by combining the weighted optimal factors. Three Canadian rivers (province of Québec were chosen as test sites. The resulting maps were assessed from historical observations and local knowledge. Results show that 77 % of the observed ice jam sites on record occurred in river sections that the model considered as having high or medium predisposition. This leaves 23 % of false negative errors (missed occurrence. Between 7 and 11 % of the highly predisposed river sections did not have an ice jam on record (false-positive cases. Results, limitations, and potential improvements are discussed.

  9. Phantom jam avoidance through in-car speed advice

    NARCIS (Netherlands)

    Suijs, L.C.W.; Wismans, Luc Johannes Josephus; Krol, L.; van Berkum, Eric C.

    2015-01-01

    The existence of phantom jams can be explained following the definition of Kerner & Konhäuser (1993) who state that a phantom jam occurs without the existence of a physical bottleneck and is caused by the imperfect driving style of road users under metastable traffic conditions. In order to prevent

  10. An Adaptive Transmitting Scheme for Interrupted Sampling Repeater Jamming Suppression

    Directory of Open Access Journals (Sweden)

    Chao Zhou

    2017-10-01

    Full Text Available The interrupted sampling repeater jamming (ISRJ based on a digital radio frequency memory (DRFM device is a new type of coherent jamming. This kind of jamming usually occurs as main-lobe jamming and has the advantages of low power requirements and easy parameter adjustment, posing a serious threat to the modern radar systems. In order to suppress the ISRJ, this paper proposes an adaptive transmitting scheme based on a phase-coded signal. The scheme firstly performs jamming perception to estimate the jamming parameters, then, on this basis, optimizes the waveform with genetic algorithm. With the optimized waveform, the jamming signal is orthogonal to the target echo, thus it can be easily suppressed with pulse compression. Simulation experiments are performed to verify the effectiveness of the scheme and the results suggest that the peak-to-side-lobe ratio (PSR and integrated side-lobe level (ISL of the pulse compression can be improved by about 16 dB and 15 dB, respectively, for the case where the jamming-to-signal ratio (JSR is 13 dB.

  11. An Adaptive Transmitting Scheme for Interrupted Sampling Repeater Jamming Suppression.

    Science.gov (United States)

    Zhou, Chao; Liu, Feifeng; Liu, Quanhua

    2017-10-29

    The interrupted sampling repeater jamming (ISRJ) based on a digital radio frequency memory (DRFM) device is a new type of coherent jamming. This kind of jamming usually occurs as main-lobe jamming and has the advantages of low power requirements and easy parameter adjustment, posing a serious threat to the modern radar systems. In order to suppress the ISRJ, this paper proposes an adaptive transmitting scheme based on a phase-coded signal. The scheme firstly performs jamming perception to estimate the jamming parameters, then, on this basis, optimizes the waveform with genetic algorithm. With the optimized waveform, the jamming signal is orthogonal to the target echo, thus it can be easily suppressed with pulse compression. Simulation experiments are performed to verify the effectiveness of the scheme and the results suggest that the peak-to-side-lobe ratio (PSR) and integrated side-lobe level (ISL) of the pulse compression can be improved by about 16 dB and 15 dB, respectively, for the case where the jamming-to-signal ratio (JSR) is 13 dB.

  12. Jamming of Knots along a Tensioned Chain

    Science.gov (United States)

    Doyle, Patrick; Narsimhan, Vivek; Renner, C. Benjamin

    In the limit of very long chains, coiled polymers almost always self-entangle and form knots. In this study, we characterize the motion of these knots along the chain contour when the chain is under very high tension. In this regime, we find that the knot exhibits glassy physics. For example, instead of moving continuously along the contour, the knot becomes kinetically trapped in long-lived, metastable states. This caging phenomenon follows Poisson statistics, and thus the long-time dynamics of the knot are diffusive. We quantify the long-time diffusivity of knots of various topologies, and we find that the diffusivity decays exponentially with increasing chain tension. The rate-of-decay of these transport properties is relatively insensitive to the knot's topology, which can be explained by examining the energy landscape of the self-reptation moves of the knot along the chain. Finally, we examine the role of bending and excluded volume interactions on this jamming phenomenon. Bending plays the biggest role in determining the onset of jamming, but the corrugation of the excluded volume interactions solely determines the rate-of-decay of the knot's transport properties. Now at Liquiglide.

  13. Pinning Susceptibility Near the Jamming Transition

    Science.gov (United States)

    Nashed, Samer; Graves, Amy; Goodrich, Carl; Padgett, Elliot; Liu, Andrea

    2014-03-01

    The study of jamming in the presence of pinned obstacles is of both practical and theoretical interest. In simulations of soft, bidisperse disks and spheres, we pin a small fraction, nf of particles prior to the equilibration process. The presence of pinned particles is known to lower the critical packing fraction, ϕJ, for jamming. Further, around this threshold there is a peak in a quantity which we have termed the ``pinning susceptibility'': χP =limnf --> 0∂PJ(ϕ/,nf) ∂nf . In the thermodynamic limit, we have posited that χP ~| Δϕ | -γP . Finite-size scaling calculations, involving careful fits of PJ to logistic sigmoidal functions, yield a value for the critical exponent, γP. This new exponent is proposed to be independent of inter-particle potential. Its dependence on dimensionality (2 vs. 3 dimensions) will be discussed. Acknowledgement is made to the Donors of the Petroleum Research Fund administered by the American Chemical Society, NSF grant DMR-1062638 and DOE grant DE-FG02-05ER46199.

  14. Effect of calcium chelators on heat coagulation and heat-induced changes of concentrated micellar casein solutions: The role of calcium-ion activity and micellar integrity

    NARCIS (Netherlands)

    Kort, de E.J.P.; Minor, M.; Snoeren, T.A.L.; Hooijdonk, van A.C.M.; Linden, van der E.

    2012-01-01

    There is general consensus that calcium chelators enhance heat stability in milk. However, they increase the heat stability to considerably different extents. For this reason, the effect of various calcium chelators on heat coagulation and heat-induced changes of concentrated micellar casein

  15. Heat stress induced, ligand-independent MET and EGFR signalling in hepatocellular carcinoma.

    Science.gov (United States)

    Thompson, Scott M; Jondal, Danielle E; Butters, Kim A; Knudsen, Bruce E; Anderson, Jill L; Stokes, Matthew P; Jia, Xiaoying; Grande, Joseph P; Roberts, Lewis R; Callstrom, Matthew R; Woodrum, David A

    2017-11-06

    The aims of the present study were 2-fold: first, to test the hypothesis that heat stress induces MET and EGFR signalling in hepatocellular carcinoma (HCC) cells and inhibition of this signalling decreases HCC clonogenic survival; and second, to identify signalling pathways associated with heat stress induced MET signalling. MET(+) and EGFR(+) HCC cells were pre-treated with inhibitors to MET, EGFR, PI3K/mTOR or vehicle and subjected to heat stress or control ± HGF or EGF growth factors and assessed by colony formation assay, Western blotting and/or quantitative mass spectrometry. IACUC approved partial laser thermal or sham ablation was performed on orthotopic N1S1 and AS30D HCC tumours and liver/tumour assessed for phospho-MET and phospho-EGFR immunostaining. Heat-stress induced rapid MET and EGFR phosphorylation that is distinct from HGF or EGF in HCC cells and thermal ablation induced MET but not EGFR phosphorylation at the HCC tumour ablation margin. Inhibition of the MET and EGFR blocked both heat stress and growth factor induced MET and EGFR phosphorylation and inhibition of MET decreased HCC clonogenic survival following heat stress. Pathway analysis of quantitative phosphoproteomic data identified downstream pathways associated with heat stress induced MET signalling including AKT, ERK, Stat3 and JNK. However, inhibition of heat stress induced MET signalling did not block AKT signalling. Heat-stress induced MET and EGFR signalling is distinct from growth factor mediated signalling in HCC cells and MET inhibition enhances heat stress induced HCC cell killing via a PI3K/AKT/mTOR-independent mechanism.

  16. Deconditioning-induced exercise responses as influenced by heat acclimation

    Science.gov (United States)

    Shvartz, E.; Bhattacharya, A.; Sperinde, S. J.; Brock, P. J.; Sciaraffa, D.; Haines, R. F.; Greenleaf, J. E.

    1979-01-01

    A study to determine the effect of heat acclimation and physical training in temperate conditions on changes in exercise tolerance following water-immersion deconditioning is presented. Five young men were tested on a bicycle ergometer before and after heat acclimation and after water immersion. The subjects and the experimental procedure, heat acclimation and exercise training, water immersion, and exercise tolerance are discussed. Heat acclimation resulted in the usual decreases in exercise heart rate and rectal temperature and an increase in sweat rate. Water immersion resulted in substantial diuresis despite water consumed. The results show that heat acclimation provides an effective method of preventing the adverse effects of water-immersion deconditioning on exercise tolerance.

  17. Acceptability of Aloysia citriodora-supplemented peach jams.

    Science.gov (United States)

    Gámbaro, Adriana; Miraballes, Marcelo; Purtscher, Irene; Deandréis, Inés; Martínez, Mariana

    2015-01-01

    An unsupplemented peach jam and four peach jam samples prepared by supplementing the former with increasing amounts of Aloysia citriodora aqueous extract were subjected to sensory testing. A trained panel of eight assessors initially identified (reaching consensus) the relevant sensory attributes and then rated the jam samples on an individual basis. The jam samples were later evaluated for overall liking and willingness to purchase by a group of 95 interested consumers, who also provided their individual appraisal of the sensory features of the various samples by responding to an open-ended question. Overall, consumers appeared not to accept the sensory modifications introduced in traditional peach jam by the addition of A. citriodora extract, even though they were expressly acquainted with its health benefits. The degree of acceptance of the extract supplement decreased significantly with increasing amounts of extract in the jam. The groups identified to have the least and the greatest tolerance to the sensory modifications introduced in the supplemented jams differed in gender distribution, with male consumers having a greater tolerance than females. © The Author(s) 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  18. River channel's predisposition to ice jams: a geospatial model

    Science.gov (United States)

    De Munck, S.; Gauthier, Y.; Bernier, M.; Légaré, S.

    2012-04-01

    When dynamic breakup occurs on rivers, ice moving downstream may eventually stop at an obstacle when the volume of moving ice exceeds the transport capacity of the river, resulting into an ice jam. The suddenness and unpredictability of these ice jams are a constant danger to local population. Therefore forecasting methods are necessary to provide an early warning to these population. Nonetheless the morphological and hydrological factors controlling where and how the ice will jam are numerous and complex. Existing studies which exist on this topic are highly site specific. Therefore, the goal of this work is to develop a simplified geospatial model that would estimate the predisposition of any river channel to ice jams. The question here is not to predict when the ice will break up but rather to know where the released ice would be susceptible to jam. This paper presents the developments and preliminary results of the proposed approach. The initial step was to document the main factors identified in the literature, as potential cause for an ice jam. First, several main factors identified in the literature as potential cause for an ice jam have been selected: presence of an island, narrowing of the channel, sinuosity, presence of a bridge, confluence of rivers and slope break. The second step was to spatially represent, in 2D, the physical characteristics of the channel and to translate these characteristics into potential ice jamming factors. The Chaudiere River, south of Quebec City (Canada), was chosen as a test site. Tools from the GIS-based FRAZIL system have been used to generate these factors from readily available geospatial data and calcutate an "ice jam predisposition index" over regular-spaced segments along the entire channel. The resulting map was validated upon historical observations and local knowledge, collected in relationship with the Minister of Public Security.

  19. Expression of the heat shock gene clpL of Streptococcus thermophilus is induced by both heat and cold shock

    Directory of Open Access Journals (Sweden)

    Naclerio Gino

    2006-02-01

    Full Text Available Abstract Background Heat and cold shock response are normally considered as independent phenomena. A small amount of evidence suggests instead that interactions may exist between them in two Lactococcus strains. Results We show the occurrence of molecular relationships between the mechanisms of cold and heat adaptations in Streptococcus thermophilus, a lactic acid bacterium widely used in dairy fermentation, where it undergoes both types of stress. We observed that cryotolerance is increased when cells are pre-incubated at high temperature. In addition, the production of a protein, identified as ClpL, a member of the heat-shock ATPase family Clp A/B, is induced at both high and low temperature. A knock-out clpL mutant is deficient in both heat and cold tolerance. However lack of production of this protein does not abolish the positive effect of heat pre-treatment towards cryotolerance. Conclusion Dual induction of ClpL by cold and heat exposure of cells and reduced tolerance to both temperature shocks in a clpL mutant indicates that the two stress responses are correlated in S. thermophilus. However this protein is not responsible by itself for cryotolerance of cells pre-treated at high temperature, indicating that ClpL is necessary for the two phenomena, but does not account by itself for the relationships between them.

  20. Heat-induced whey protein isolate fibrils: Conversion, hydrolysis, and disulphide bond formation

    NARCIS (Netherlands)

    Bolder, S.G.; Vasbinder, A.; Sagis, L.M.C.; Linden, van der E.

    2007-01-01

    Fibril formation of individual pure whey proteins and whey protein isolate (WPI) was studied. The heat-induced conversion of WPI monomers into fibrils at pH 2 and low ionic strength increased with heating time and protein concentration. Previous studies, using a precipitation method, size-exclusion

  1. Heat-inducible Cre-lox system for marker excision in transgenic rice

    Indian Academy of Sciences (India)

    The present study assessed the efficacy of a heat-inducible cre gene for conditional removal of the marker gene from a rice genome via Cre-lox recombination. A cre gene controlled by the soybean heat-shock promoter was introduced into the rice genome along with the recombination target (lox) construct. Cre-mediated ...

  2. Detailing radio frequency heating induced by coronary stents: a 7.0 Tesla magnetic resonance study.

    Directory of Open Access Journals (Sweden)

    Davide Santoro

    Full Text Available The sensitivity gain of ultrahigh field Magnetic Resonance (UHF-MR holds the promise to enhance spatial and temporal resolution. Such improvements could be beneficial for cardiovascular MR. However, intracoronary stents used for treatment of coronary artery disease are currently considered to be contra-indications for UHF-MR. The antenna effect induced by a stent together with RF wavelength shortening could increase local radiofrequency (RF power deposition at 7.0 T and bears the potential to induce local heating, which might cause tissue damage. Realizing these constraints, this work examines RF heating effects of stents using electro-magnetic field (EMF simulations and phantoms with properties that mimic myocardium. For this purpose, RF power deposition that exceeds the clinical limits was induced by a dedicated birdcage coil. Fiber optic probes and MR thermometry were applied for temperature monitoring using agarose phantoms containing copper tubes or coronary stents. The results demonstrate an agreement between RF heating induced temperature changes derived from EMF simulations versus MR thermometry. The birdcage coil tailored for RF heating was capable of irradiating power exceeding the specific-absorption rate (SAR limits defined by the IEC guidelines by a factor of three. This setup afforded RF induced temperature changes up to +27 K in a reference phantom. The maximum extra temperature increase, induced by a copper tube or a coronary stent was less than 3 K. The coronary stents examined showed an RF heating behavior similar to a copper tube. Our results suggest that, if IEC guidelines for local/global SAR are followed, the extra RF heating induced in myocardial tissue by stents may not be significant versus the baseline heating induced by the energy deposited by a tailored cardiac transmit RF coil at 7.0 T, and may be smaller if not insignificant than the extra RF heating observed under the circumstances used in this study.

  3. Attribution and mitigation of heat wave-induced urban heat storage change

    Science.gov (United States)

    Sun, Ting; Kotthaus, Simone; Li, Dan; Ward, H. C.; Gao, Zhiqiu; Ni, Guang-Heng; Grimmond, C. S. B.

    2017-11-01

    When the urban heat island (UHI) effect coincides with a heat wave (HW), thermal stress in cities is exacerbated. Understanding the surface energy balance (SEB) responses to HWs is critical for improving predictions of the synergies between UHIs and HWs. This study evaluates observed SEB characteristics in four cities (Beijing, Łódź, London and Swindon), along with their ambient meteorological conditions, for both HW and background summer climate scenarios. Using the Analytical Objective Hysteresis Model (AnOHM), particular emphasis is on the heat storage. The results demonstrate that in London and Swindon the amount of daytime heat storage and its fraction relative to the net all-wave radiation increase under HWs. Results further demonstrate that such increases are strongly tied to lower wind speeds. The effects of different UHI mitigation measures on heat storage are assessed using AnOHM. Results reveal that use of reflective materials and maintaining higher soil moisture availability can offset the adverse effects of increased heat storage.

  4. Novel anti-jamming technique for OCDMA network through FWM in SOA based wavelength converter

    Science.gov (United States)

    Jyoti, Vishav; Kaler, R. S.

    2013-06-01

    In this paper, we propose a novel anti-jamming technique for optical code division multiple access (OCDMA) network through four wave mixing (FWM) in semiconductor optical amplifier (SOA) based wavelength converter. OCDMA signal can be easily jammed with high power jamming signal. It is shown that wavelength conversion through four wave mixing in SOA has improved capability of jamming resistance. It is observed that jammer has no effect on OCDMA network even at high jamming powers by using the proposed technique.

  5. HMF formation and colour change of bitter orange and sweet orange jams during storage

    OpenAIRE

    Kopjar, Mirela; Đurkan, Ivana; Piližota, Vlasta

    2010-01-01

    In this work influence of preparation on 5-hydroxymethylfurfural (HMF) and colour of bitter orange jams and sweet orange jams was investigated. Samples were prepared without and with treatment of oranges with ascorbic acid in order to investigate the influence on prevention of browning in jams. Samples were stored for 365 days at 4 °C and at room temperature and formation of HMF and colour change during storage were measured. After jam preparation bitter orange jams had higher HMF content tha...

  6. Measurement of heat pump processes induced by laser radiation

    Science.gov (United States)

    Garbuny, M.; Henningsen, T.

    1983-01-01

    A series of experiments was performed in which a suitably tuned CO2 laser, frequency doubled by a Tl3AsSe37 crystal, was brought into resonance with a P-line or two R-lines in the fundamental vibration spectrum of CO. Cooling or heating produced by absorption in CO was measured in a gas-thermometer arrangement. P-line cooling and R-line heating could be demonstrated, measured, and compared. The experiments were continued with CO mixed with N2 added in partial pressures from 9 to 200 Torr. It was found that an efficient collisional resonance energy transfer from CO to N2 existed which increased the cooling effects by one to two orders of magnitude over those in pure CO. Temperature reductions in the order of tens of degrees Kelvin were obtained by a single pulse in the core of the irradiated volume. These measurements followed predicted values rather closely, and it is expected that increase of pulse energies and durations will enhance the heat pump effects. The experiments confirm the feasibility of quasi-isentropic engines which convert laser power into work without the need for heat rejection. Of more immediate potential interest is the possibility of remotely powered heat pumps for cryogenic use, such applications are discussed to the extent possible at the present stage.

  7. Cooperative Jamming for Physical Layer Security in Wireless Sensor Networks

    DEFF Research Database (Denmark)

    Rohokale, Vandana M.; Prasad, Neeli R.; Prasad, Ramjee

    2012-01-01

    Interference is generally considered as the redundant and unwanted occurrence in wireless communication. This work proposes a novel cooperative jamming mechanism for scalable networks like Wireless Sensor Networks (WSNs) which makes use of friendly interference to confuse the eavesdropper...

  8. JAM-C regulates unidirectional monocyte transendothelial migration in inflammation.

    Science.gov (United States)

    Bradfield, Paul F; Scheiermann, Christoph; Nourshargh, Sussan; Ody, Christiane; Luscinskas, Francis W; Rainger, G Ed; Nash, Gerard B; Miljkovic-Licina, Marijana; Aurrand-Lions, Michel; Imhof, Beat A

    2007-10-01

    Monocyte recruitment from the vasculature involves sequential engagement of multiple receptors, culminating in transendothelial migration and extravasation. Junctional adhesion molecule-C (JAM-C) is localized at endothelial intercellular junctions and plays a role in monocyte transmigration. Here, we show that blockade of JAM-B/-C interaction reduced monocyte numbers in the extravascular compartment through increased reverse transmigration rather than by reduced transmigration. This was confirmed in vivo, showing that an anti-JAM-C antibody reduced the number of monocytes in inflammatory tissue and increased the number of monocytes with a reverse-transmigratory phenotype in the peripheral blood. All together, our results suggest a novel mechanism of reducing accumulation of monocytes at inflammation sites by disruption of JAM-C-mediated monocyte retention.

  9. Tracking Launch Vehicles in Interference and Jamming Project

    Data.gov (United States)

    National Aeronautics and Space Administration — MARK Resources proposes to develop a method for combining a set of distributed FRPAs into a network that provides high GPS anti-jam/interference capability. Like a...

  10. Frequency and Polarization Diversity Jamming of Communications in Urban Environments

    National Research Council Canada - National Science Library

    Ulama, Tuncay

    2005-01-01

    The purpose of this research is to investigate how to exploit frequency and polarization techniques in reducing the effects of jamming against UAV relay communication links in an urban warfare environment...

  11. Experimental simulation of retrodirective cross-eye jamming

    CSIR Research Space (South Africa)

    Du Plessis, WP

    2010-01-01

    Full Text Available Experimental measurements that accurately simulate the effect of a retrodirective cross-eye jammer on a monopulse radar are described. The accuracy of a recently published extended analysis of retrodirective crosseye jamming and the limitations...

  12. Bats jamming bats: food competition through sonar interference.

    Science.gov (United States)

    Corcoran, Aaron J; Conner, William E

    2014-11-07

    Communication signals are susceptible to interference ("jamming") from conspecifics and other sources. Many active sensing animals, including bats and electric fish, alter the frequency of their emissions to avoid inadvertent jamming from conspecifics. We demonstrated that echolocating bats adaptively jam conspecifics during competitions for food. Three-dimensional flight path reconstructions and audio-video field recordings of foraging bats (Tadarida brasiliensis) revealed extended interactions in which bats emitted sinusoidal frequency-modulated ultrasonic signals that interfered with the echolocation of conspecifics attacking insect prey. Playbacks of the jamming call, but not of control sounds, caused bats to miss insect targets. This study demonstrates intraspecific food competition through active disruption of a competitor's sensing during food acquisition. Copyright © 2014, American Association for the Advancement of Science.

  13. Shear Yielding and Shear Jamming of Dense Hard Sphere Glasses.

    Science.gov (United States)

    Urbani, Pierfrancesco; Zamponi, Francesco

    2017-01-20

    We investigate the response of dense hard sphere glasses to a shear strain in a wide range of pressures ranging from the glass transition to the infinite-pressure jamming point. The phase diagram in the density-shear strain plane is calculated analytically using the mean-field infinite-dimensional solution. We find that just above the glass transition, the glass generically yields at a finite shear strain. The yielding transition in the mean-field picture is a spinodal point in presence of disorder. At higher densities, instead, we find that the glass generically jams at a finite shear strain: the jamming transition prevents yielding. The shear yielding and shear jamming lines merge in a critical point, close to which the system yields at extremely large shear stress. Around this point, highly nontrivial yielding dynamics, characterized by system-spanning disordered fractures, is expected.

  14. Chemical and Sensorial Evaluation of a Newly Developed Bean Jam

    OpenAIRE

    Guiné, Raquel; Figueiredo, Ana; Correia, Paula; Gonçalves, Fernando

    2015-01-01

    The purpose of the present work was to develop an innovative food product with nutritional properties as well as appealing organoleptic qualities. The product, a jam, was prepared with the beans’ cooking water combined with fresh apple or carrot, without the addition of any conservatives. Three different jams were produced: bean and carrot, bean and apple and bean, apple and cinnamon. The developed products underwent a sensorial...

  15. The bursting of housing bubble as jamming phase transition

    Science.gov (United States)

    Nishinari, Katsuhiro; Iwamura, Mitsuru; Umeno Saito, Yukiko; Watanabe, Tsutomu

    2010-04-01

    In this paper, we have proposed a bubble burst model by focusing on transaction volume incorporating a traffic model that represents spontaneous traffic jam. We find that the phenomenon of bubble burst shares many similar properties with traffic jam formation on highway by comparing data taken from the U.S. housing market. Our result suggests that transaction volume could be a driving force of bursting phenomenon.

  16. A Study of Heat Flux Induced Dryout in Capillary Grooves

    Science.gov (United States)

    1992-12-01

    to operate the heat pipe at or near maximum heat transfer conditions. One of the problems with maximizing the performance is the danger of living on...the characteristic dimension of the groove or pore. At this point, the pressure gradient between the condenser and evaporator is maximized , and...Note: T1|=25 - -142- RUN LETTER DESl •GATION: T9 DATE: 10-02-1992 TIME: 14:55:48 GROOVE NIB R: I THEB MRMETRIC PRESSURE IS 29.011 M OF IMER Y THE

  17. Interplay between thermal percolation and jamming upon dimer adsorption on binary alloys

    Science.gov (United States)

    Loscar, Ernesto S.; Borzi, R. A.; Albano, Ezequiel V.

    2006-11-01

    By means of Monte Carlo simulations we study jamming and percolation processes upon the random sequential adsorption of dimers on binary alloys with different degrees of structural order. The substrates are equimolar mixtures that we simulate using an Ising model with conserved order parameter. After an annealing at temperature T we quench the alloys to freeze the state of order of the surface at this temperature. The deposition is then performed neglecting thermal effects like surface desorption or diffusion. In this way, the annealing temperature is a continuous parameter that characterizes the adsorbing surfaces, shaping the deposition process. As the alloys undergo an order-disorder phase transition at the Onsager critical temperature (Tc) , the jamming and percolating properties of the set of deposited dimers are subjected to nontrivial changes, which we summarize in a density-temperature phase diagram. We find that for TT* . Particular attention is focused close to T* , where the interplay between jamming and percolation restricts fluctuations, forcing exponents seemingly different from the standard percolation universality class. By analogy with a thermal transition, we study the onset of percolation using the temperature T as a control parameter. We propose thermal scaling Ansätze to analyze the behavior of the percolation threshold and its thermally induced fluctuations. Also, the fractal dimension of the percolating cluster is determined. Based on these measurements and the excellent data collapse, we conclude that the universality class of standard percolation is preserved for all temperatures.

  18. Extracellular vesicles released following heat stress induce bystander effect in unstressed populations.

    Science.gov (United States)

    Bewicke-Copley, Findlay; Mulcahy, Laura Ann; Jacobs, Laura Ann; Samuel, Priya; Akbar, Naveed; Pink, Ryan Charles; Carter, David Raul Francisco

    2017-01-01

    Cells naïve to stress can display the effects of stress, such as DNA damage and apoptosis, when they are exposed to signals from stressed cells; this phenomenon is known as the bystander effect. We previously showed that bystander effect induced by ionising radiation are mediated by extracellular vesicles (EVs). Bystander effect can also be induced by other types of stress, including heat shock, but it is unclear whether EVs are involved. Here we show that EVs released from heat shocked cells are also able to induce bystander damage in unstressed populations. Naïve cells treated with media conditioned by heat shocked cells showed higher levels of DNA damage and apoptosis than cells treated with media from control cells. Treating naïve cells with EVs derived from media conditioned by heat shocked cells also induced a bystander effect when compared to control, with DNA damage and apoptosis increasing whilst the level of cell viability was reduced. We demonstrate that treatment of naïve cells with heat shocked cell-derived EVs leads to greater invasiveness in a trans-well Matrigel assay. Finally, we show that naïve cells treated with EVs from heat-shocked cells are more likely to survive a subsequent heat shock, suggesting that these EVs mediate an adaptive response. We propose that EVs released following stress mediate an intercellular response that leads to apparent stress in neighbouring cells but also greater robustness in the face of a subsequent insult.

  19. Jamming of Cylindrical Grains in Featureless Vertical Channels

    Science.gov (United States)

    Baxter, G. William; Barr, Nicholas; Weible, Seth; Friedl, Nicholas

    2013-03-01

    We study jamming of low aspect-ratio cylindrical Delrin grains falling through a featureless vertical channel. With a grain height less than the grain diameter, these grains resemble aspirin tablets, poker chips, or coins. Unidisperse grains are allowed to fall under the influence of gravity through a uniform channel of square cross-section where the channel width is greater than the grain size and constant along the length of the channel. Channel widths are chosen so that no combination of grain heights and diameters is equal to the channel width. Collections of grains sometimes form jams, stable structures in which the grains are supported by the channel walls and not by grains or walls beneath them. The probability of a jam occurring and the jam's strength are influenced by the grain dimensions and channel width. We will present experimental measurements of the jamming probability and jam strength and discuss the relationship of these results to other experiments and theories. Supported by an Undergraduate Research Grant from Penn State Erie, The Behrend College

  20. Jamming of Monodisperse Cylindrical Grains in Featureless Vertical Channels

    Science.gov (United States)

    Friedl, Nicholas; Baxter, G. William

    2014-03-01

    We study jamming of low aspect-ratio cylindrical Delrin grains falling through a featureless vertical channel under the influence of gravity. These grains have an aspect-ratio less than two (H/D aspirin tablets, 35mm film canisters, poker chips, or coins. Monodisperse grains are allowed to fall under the influence of gravity through a uniform channel of square cross-section where the channel width is greater than the grain size and constant along the length of the channel. No combination of grain heights and diameters is equal to the channel width. Collections of grains sometimes form jams, stable structures in which the grains are supported by the channel walls and not by grains or walls beneath them. The probability of a jam occurring and the jam's strength are influenced by the grain dimensions and channel width. We will present experimental measurements of the jamming probability and jam strength and discuss the relationship of these results to other experiments and theories. Supported by an Undergraduate Research Grant from Penn State Erie, The Behrend College.

  1. Jam-absorption driving with a car-following model

    Science.gov (United States)

    Taniguchi, Yohei; Nishi, Ryosuke; Ezaki, Takahiro; Nishinari, Katsuhiro

    2015-09-01

    Jam-absorption driving (JAD) refers to the action performed by a single car to dynamically change its headway to remove a traffic jam. Because of its irregular motion, a car performing JAD perturbs other cars following it, and these perturbations may grow to become the so-called secondary traffic jams. A basic theory for JAD (Nishi et al. 2013) does not consider accelerations of cars or the stability of traffic flow. In this paper, by introducing car-following behaviors, we implement these elements in JAD. Numerous previous studies on the instability of traffic flow showed that even in a region whose density is below a critical density, perturbation may grow if its initial magnitude is large. According to these previous studies, we expect that the perturbations caused by JAD, if they are sufficiently small, do not grow to become secondary traffic jams. Using a microscopic car-following model, we numerically confirmed that the stability of a flow obeying the model depends on the magnitude of JAD perturbations. On the basis of this knowledge, numerical results indicate that parameter regions exist where JAD allows traffic jams to be removed without causing secondary traffic jams. Moreover, JAD is robust against a parameter of acceleration in the model, as well as the choice of car-following models.

  2. Self-heating effect induced by ion bombardment on polycrystalline ...

    Indian Academy of Sciences (India)

    to the self-heating effect by energy exchange between incident ions and Al surface, and the suppression by conti- nuous ion bombardment with a .... The temperature of the water-cooled substrate holder was fixed at 15. ◦. C. The Ar. + ... as the interaction between continuous ion bombardment and isotropic diffusion on the ...

  3. Traffic jam driving with NMV avoidance

    Science.gov (United States)

    Milanés, Vicente; Alonso, Luciano; Villagrá, Jorge; Godoy, Jorge; de Pedro, Teresa; Oria, Juan P.

    2012-08-01

    In recent years, the development of advanced driver assistance systems (ADAS) - mainly based on lidar and cameras - has considerably improved the safety of driving in urban environments. These systems provide warning signals for the driver in the case that any unexpected traffic circumstance is detected. The next step is to develop systems capable not only of warning the driver but also of taking over control of the car to avoid a potential collision. In the present communication, a system capable of autonomously avoiding collisions in traffic jam situations is presented. First, a perception system was developed for urban situations—in which not only vehicles have to be considered, but also pedestrians and other non-motor-vehicles (NMV). It comprises a differential global positioning system (DGPS) and wireless communication for vehicle detection, and an ultrasound sensor for NMV detection. Then, the vehicle's actuators - brake and throttle pedals - were modified to permit autonomous control. Finally, a fuzzy logic controller was implemented capable of analyzing the information provided by the perception system and of sending control commands to the vehicle's actuators so as to avoid accidents. The feasibility of the integrated system was tested by mounting it in a commercial vehicle, with the results being encouraging.

  4. Astragaloside-IV Alleviates Heat-Induced Inflammation by Inhibiting Endoplasmic Reticulum Stress and Autophagy.

    Science.gov (United States)

    Dong, Zhiwei; Zhou, Jian; Zhang, Ying; Chen, Yajie; Yang, Zichen; Huang, Guangtao; Chen, Yu; Yuan, Zhiqiang; Peng, Yizhi; Cao, Tongtong

    2017-01-01

    Thermal injury is the main cause of pulmonary disease in stroke after burn and can be life threatening. Heat-induced inflammation is an important factor that triggers a series of induces pathological changes. However, this mechanism underlying heat-induced inflammation in thermal inhalation injury remains unclear. Studies have revealed that astragaloside-IV (AS-IV), a natural compound extracted from Astragalus membranaceus, has protective effects in inflammatory diseases. Here, we investigated whether the protective effects of AS-IV occur because of the suppression of heat-induced endoplasmic reticulum (ER) stress and excessive autophagy Methods: AS-IV was administered to Wistar rats after thermal inhalation injury and 16HBE140-cells were treated with AS-IV. TNF-α, IL-6, and IL-8 levels were determined by ELISA and real-time PCR. ER stress and autophagy were determined by western blot. Autophagic flux was measured by recording the fluorescence emission of the fusion protein mRFP-GFP-LC3 by dynamic live-cell imaging. AS-IV had protective effects against heat-induced reactive oxygen species production and attenuated ER stress. AS IV alleviated heat-induced excessive autophagy in vitro and in vivo. Excessive autophagy was attenuated by the PERK inhibitor GSK2656157 and eIF2α siRNA, suggesting that heat stress-induced autophagy can activate the PERK-eIF2α pathway. Beclin 1 and Atg5 siRNAs inhibited the upregulation of the inflammatory cytokines TNF-α, IL-6, and IL-8 after heat exposure. Thus, AS-IV may attenuate inflammatory responses by disrupting the crosstalk between autophagy and the PERK-eIF2α pathway and may be an ideal agent for treating inflammatory pulmonary diseases. © 2017 The Author(s). Published by S. Karger AG, Basel.

  5. Spatial summation of heat induced pain within and between dermatomes.

    Science.gov (United States)

    Nielsen, J; Arendt-Nielsen, L

    1997-01-01

    The aim was to study spatial summation within and between ipsi- and contralateral dermatomes at different painful temperatures. For heat stimulation we used a computer controlled thermofoil based thermode. The thermode area could be varied in five discrete steps from 3.14 to 15.70 cm2. When we applied the stimuli within a dermatome, the mean heat pain threshold decreased significantly from 45.6 to 43.5 degrees C as the area was increased from minimum (3.14 cm2) to maximum (15.70 cm2). When the areas were increased involving different dermatomes (both ipsi- or contralateral), we found similar decreases in pain threshold. Spatial summation was also found within and between dermatomes at supra-threshold temperatures (46, 48, 50 degrees C). The study shows that spatial summation of pain is most likely a mechanism acting across segments and is existing from pain threshold to tolerance.

  6. Liquid film dewetting induced by impulsive Joule heating

    Science.gov (United States)

    Mayer, H. C.; Krechetnikov, R.

    2017-09-01

    Motivated by the need for understanding the boiling processes in three-phase microscopic systems, the present work aims to uncover the physics of forced dewetting of a liquid film initially attached to a metal wire frame, which is heated with a rate up to O (108) K s-1 by discharging a capacitor impulsively. Depending on the corresponding heat flux ≤O (1011) J m-2 , there are several key dewetting regimes—no detachment, nonuniform detachment, and uniform detachment of a film—differentiated by boiling transitions in the film Plateau borders. Transitions between these regimes prove to occur, for various wire diameters and frame sizes, around the same values of the capacitor energy per unit wire volume. Also, an intrinsic transverse instability manifesting itself in the formation of fingers along the detached liquid film rim is discovered and analyzed in detail.

  7. Non-Specific Protein Modifications by a Phytochemical Induce Heat Shock Response for Self-Defense

    Science.gov (United States)

    Ohnishi, Kohta; Ohkura, Shinya; Nakahata, Erina; Ishisaka, Akari; Kawai, Yoshichika; Terao, Junji; Mori, Taiki; Ishii, Takeshi; Nakayama, Tsutomu; Kioka, Noriyuki; Matsumoto, Shinya; Ikeda, Yasutaka; Akiyama, Minoru; Irie, Kazuhiro; Murakami, Akira

    2013-01-01

    Accumulated evidence shows that some phytochemicals provide beneficial effects for human health. Recently, a number of mechanistic studies have revealed that direct interactions between phytochemicals and functional proteins play significant roles in exhibiting their bioactivities. However, their binding selectivities to biological molecules are considered to be lower due to their small and simple structures. In this study, we found that zerumbone, a bioactive sesquiterpene, binds to numerous proteins with little selectivity. Similar to heat-denatured proteins, zerumbone-modified proteins were recognized by heat shock protein 90, a constitutive molecular chaperone, leading to heat shock factor 1-dependent heat shock protein induction in hepa1c1c7 mouse hepatoma cells. Furthermore, oral administration of this phytochemical up-regulated heat shock protein expressions in the livers of Sprague-Dawley rats. Interestingly, pretreatment with zerumbone conferred a thermoresistant phenotype to hepa1c1c7 cells as well as to the nematode Caenorhabditis elegans. It is also important to note that several phytochemicals with higher hydrophobicity or electrophilicity, including phenethyl isothiocyanate and curcumin, markedly induced heat shock proteins, whereas most of the tested nutrients did not. These results suggest that non-specific protein modifications by xenobiotic phytochemicals cause mild proteostress, thereby inducing heat shock response and leading to potentiation of protein quality control systems. We considered these bioactivities to be xenohormesis, an adaptation mechanism against xenobiotic chemical stresses. Heat shock response by phytochemicals may be a fundamental mechanism underlying their various bioactivities. PMID:23536805

  8. Combined active and passive heat exposure induced heat acclimation in a soccer referee before 2014 FIFA World Cup.

    Science.gov (United States)

    Ruddock, A D; Thompson, S W; Hudson, S A; James, C A; Gibson, O R; Mee, J A

    2016-01-01

    The 2014 FIFA World Cup was held in Brazil, where the climatic conditions presented a significant thermoregulatory and perceptual challenge to those unfamiliar with the heat and humidity. This case report documents the adaptation induced by a novel mixed methods (isothermic and passive) heat acclimation (HA) regime for a northern European professional soccer match official prior to the tournament. The intervention involved 13 HA sessions over an 18 day period comprising five isothermic HA sessions whereby intermittent running was used to target and maintain tympanic temperature (Tytemp) at 38 °C for 90 min, and seven passive HA sessions of 48 °C water bathing for 30 min. The athlete performed a heat stress test (HST) (35 min running at four incremental intensities in 30 °C) and a repeated high-intensity running test (as many 30 s self-paced efforts as possible, to a maximum of 20, with 30 s passive recovery) before and after the intervention. The mixed methods HA regime increased plasma volume (+7.1 %), and sweat loss (+0.9 L h(-1)), reduced exercising Tytemp (-0.6 °C), and mean body temperature (-0.5 °C). High-intensity running performance improved after HA (+29 %), as did the perception of thermal comfort during exercise (-0.3 units). This data evidences the effectiveness of a practical, mixed methods HA strategy, remotely implemented around training and competition, at inducing the heat acclimation phenotype in a high-level soccer match official.

  9. Laser Induced Fluorescence (LIF) Nondestructive Evaluation of Incipient Heat Damage in Polymer Matrix Composites, A2476

    Science.gov (United States)

    2017-02-15

    02-2017 2. REPORT TYPE Final 3. DATES COVERED (From - To) Oct 2011 - Jul 2016 4. TITLE AND SUBTITLE Laser Induced Fluorescence (LIF...Instances of mechanical strength degradation from incipient heat damage in aircraft PMCs exceeding 60% have been reported (Fisher et al., 1995). Currently...forms of exposure. Bowie’s master’s thesis (2017) includes a review of the scientific and engineering literature on incipient heat damage in PMCs

  10. Oncostatin M induces heat hypersensitivity by gp130-dependent sensitization of TRPV1 in sensory neurons

    Directory of Open Access Journals (Sweden)

    Langeslag Michiel

    2011-12-01

    Full Text Available Abstract Oncostatin M (OSM is a member of the interleukin-6 cytokine family and regulates eg. gene activation, cell survival, proliferation and differentiation. OSM binds to a receptor complex consisting of the ubiquitously expressed signal transducer gp130 and the ligand binding OSM receptor subunit, which is expressed on a specific subset of primary afferent neurons. In the present study, the effect of OSM on heat nociception was investigated in nociceptor-specific gp130 knock-out (SNS-gp130-/- and gp130 floxed (gp130fl/fl mice. Subcutaneous injection of pathophysiologically relevant concentrations of OSM into the hind-paw of C57BL6J wild type mice significantly reduced paw withdrawal latencies to heat stimulation. In contrast to gp130fl/fl mice, OSM did not induce heat hypersensitivity in vivo in SNS-gp130-/- mice. OSM applied at the receptive fields of sensory neurons in in vitro skin-nerve preparations showed that OSM significantly increased the discharge rate during a standard ramp-shaped heat stimulus. The capsaicin- and heat-sensitive ion channel TRPV1, expressed on a subpopulation of nociceptive neurons, has been shown to play an important role in inflammation-induced heat hypersensitivity. Stimulation of cultured dorsal root ganglion neurons with OSM resulted in potentiation of capsaicin induced ionic currents. In line with these recordings, mice with a null mutation of the TRPV1 gene did not show any signs of OSM-induced heat hypersensitivity in vivo. The present data suggest that OSM induces thermal hypersensitivity by directly sensitizing nociceptors via OSMR-gp130 receptor mediated potentiation of TRPV1.

  11. Controllable surface haptics via particle jamming and pneumatics.

    Science.gov (United States)

    Stanley, Andrew A; Okamura, Allison M

    2015-01-01

    The combination of particle jamming and pneumatics allows the simultaneous control of shape and mechanical properties in a tactile display. A hollow silicone membrane is molded into an array of thin cells, each filled with coffee grounds such that adjusting the vacuum level in any individual cell rapidly switches it between flexible and rigid states. The array clamps over a pressure-regulated air chamber with internal mechanisms designed to pin the nodes between cells at any given height. Various sequences of cell vacuuming, node pinning, and chamber pressurization allow the surface to balloon into a variety of shapes. Experiments were performed to expand existing physical models of jamming at the inter-particle level to define the rheological characteristics of jammed systems from a macroscopic perspective, relevant to force-displacement interactions that would be experienced by human users. Force-displacement data show that a jammed cell in compression fits a Maxwell model and a cell deflected in the center while supported only at the edges fits a Zener model, each with stiffness and damping parameters that increase at higher levels of applied vacuum. This provides framework to tune and control the mechanical properties of a jamming haptic interface.

  12. Stochastic Model of Traffic Jam and Traffic Signal Control

    Science.gov (United States)

    Shin, Ji-Sun; Cui, Cheng-You; Lee, Tae-Hong; Lee, Hee-Hyol

    Traffic signal control is an effective method to solve the traffic jam. and forecasting traffic density has been known as an important part of the Intelligent Transportation System (ITS). The several methods of the traffic signal control are known such as random walk method, Neuron Network method, Bayesian Network method, and so on. In this paper, we propose a new method of a traffic signal control using a predicted distribution of traffic jam based on a Dynamic Bayesian Network model. First, a forecasting model to predict a probabilistic distribution of the traffic jam during each period of traffic lights is built. As the forecasting model, the Dynamic Bayesian Network is used to predict the probabilistic distribution of a density of the traffic jam. According to measurement of two crossing points for each cycle, the inflow and outflow of each direction and the number of standing vehicles at former cycle are obtained. The number of standing vehicle at k-th cycle will be calculated synchronously. Next, the probabilistic distribution of the density of standing vehicle in each cycle will be predicted using the Dynamic Bayesian Network constructed for the traffic jam. And then a control rule to adjust the split and the cycle to increase the probability between a lower limit and ceiling of the standing vehicles is deduced. As the results of the simulation using the actual traffic data of Kitakyushu city, the effectiveness of the method is shown.

  13. Heat transfer in MHD flow due to a linearly stretching sheet with induced magnetic field

    CERN Document Server

    El-Mistikawy, Tarek M A

    2016-01-01

    The full MHD problem of the flow and heat transfer due to a linearly stretching sheet in the presence of a transverse magnetic field is put in a self-similar form. Traditionally ignored physical processes such as induced magnetic field, viscous dissipation, Joule heating, and work shear are included and their importance is established. Cases of prescribed surface temperature, prescribed heat flux, surface feed (injection or suction), velocity slip, and thermal slip are also considered. The problem is shown to admit self similarity. Sample numerical solutions are obtained for chosen combinations of the flow parameters.

  14. Resilience of LTE networks against smart jamming attacks

    KAUST Repository

    Aziz, Farhan M.

    2014-12-08

    Commercial LTE networks are being studied for mission-critical applications, such as public safety and smart grid communications. In this paper, LTE networks are shown vulnerable to Denial-of-Service (DOS) and loss of service attacks from smart jammers, who may employ simple narrowband jamming techniques to attack without any need to hack the network or its users. We modeled the utilities of jamming and anti-jamming actions played by the jammer and the network under the framework of single-shot and repeated Bayesian games. In a single-shot game formulation the only Nash Equilibria (NE) are pure strategy equilibria at which network utility is severely compromised. We propose a repeated-game learning and strategy algorithm for the network that outperforms single-shot games by a significant margin. Furthermore, all of our proposed actions and algorithms can be implemented with current technology.

  15. Period proliferation in periodic states in cyclically sheared jammed solids

    Science.gov (United States)

    Lavrentovich, Maxim O.; Liu, Andrea J.; Nagel, Sidney R.

    2017-08-01

    Athermal disordered systems can exhibit a remarkable response to an applied oscillatory shear: After a relatively few shearing cycles, the system falls into a configuration that had already been visited in a previous cycle. After this point the system repeats its dynamics periodically despite undergoing many particle rearrangements during each cycle. We study the behavior of orbits as we approach the jamming point in simulations of jammed particles subject to oscillatory shear at fixed pressure and zero temperature. As the pressure is lowered, we find that it becomes more common for the system to find periodic states where it takes multiple cycles before returning to a previously visited state. Thus, there is a proliferation of longer periods as the jamming point is approached.

  16. Heat

    CERN Document Server

    Lawrence, Ellen

    2016-01-01

    Is it possible to make heat by rubbing your hands together? Why does an ice cube melt when you hold it? In this title, students will conduct experiments to help them understand what heat is. Kids will also investigate concepts such as which materials are good at conducting heat and which are the best insulators. Using everyday items that can easily be found around the house, students will transform into scientists as they carry out step-by-step experiments to answer interesting questions. Along the way, children will pick up important scientific skills. Heat includes seven experiments with detailed, age-appropriate instructions, surprising facts and background information, a "conclusions" section to pull all the concepts in the book together, and a glossary of science words. Colorful, dynamic designs and images truly put the FUN into FUN-damental Experiments.

  17. Convergent evolution of heat-inducibility during subfunctionalization of the Hsp70 gene family.

    Science.gov (United States)

    Krenek, Sascha; Schlegel, Martin; Berendonk, Thomas U

    2013-02-21

    Heat-shock proteins of the 70 kDa family (Hsp70s) are essential chaperones required for key cellular functions. In eukaryotes, four subfamilies can be distinguished according to their function and localisation in different cellular compartments: cytosol, endoplasmic reticulum, mitochondria and chloroplasts. Generally, multiple cytosol-type Hsp70s can be found in metazoans that show either constitutive expression and/or stress-inducibility, arguing for the evolution of different tasks and functions. Information about the hsp70 copy number and diversity in microbial eukaryotes is, however, scarce, and detailed knowledge about the differential gene expression in most protists is lacking. Therefore, we have characterised the Hsp70 gene family of Paramecium caudatum to gain insight into the evolution and differential heat stress response of the distinct family members in protists and to investigate the diversification of eukaryotic hsp70s focusing on the evolution of heat-inducibility. Eleven putative hsp70 genes could be detected in P. caudatum comprising homologs of three major Hsp70-subfamilies. Phylogenetic analyses revealed five evolutionarily distinct Hsp70-groups, each with a closer relationship to orthologous sequences of Paramecium tetraurelia than to another P. caudatum Hsp70-group. These highly diverse, paralogous groups resulted from duplications preceding Paramecium speciation, underwent divergent evolution and were subject to purifying selection. Heat-shock treatments were performed to test for differential expression patterns among the five Hsp70-groups as well as for a functional conservation within Paramecium. These treatments induced exceptionally high mRNA up-regulations in one cytosolic group with a low basal expression, indicative for the major heat inducible hsp70s. All other groups showed comparatively high basal expression levels and moderate heat-inducibility, signifying constitutively expressed genes. Comparative EST analyses for P. tetraurelia

  18. Synergetic theory for a jamming transition in traffic flow

    Science.gov (United States)

    Olemskoi, Alexander I.; Khomenko, Alexei V.

    2001-03-01

    The theory of a jamming transition is proposed for the homogeneous car-following model within the framework of the Lorenz scheme. We represent a jamming transition as a result of the spontaneous deviations of headway and velocity that is caused by the acceleration/braking rate to be higher than the critical value. The stationary values of headway and velocity deviations and time of acceleration/braking are derived as functions of control parameter (time needed for car to take the characteristic velocity).

  19. A study of optimal abstract jamming strategies vs. noncoherent MFSK

    Science.gov (United States)

    Mceliece, R. J.; Rodemich, E. R.

    1983-01-01

    The present investigation is concerned with the performance of uncoded MFSK modulation in the presence of arbitrary additive jamming, taking into account the objective to devise robust antijamming strategies. An abstract model is considered, giving attention to the signal strength as a nonnegative real number X, the employment of X as a random variable, its distribution function G(x), the transmitter's strategy G, the jamming noise as an M-dimensional random vector Z, and the error probability. A summary of previous work on the considered problem is provided, and the results of the current study are presented.

  20. A Novel Combination of Thermal Ablation and Heat-Inducible Gene therapy for Breast Cancer Treatment

    Science.gov (United States)

    2009-04-01

    intensity focused ultrasound ( HIFU ) has been developed as an emerging non-invasive strategy for cancer treatment by thermal ablation of tumor tissue. The...feasibility of synergistic combination of HIFU thermal ablation and HIFU -induced gene therapy is interpreted both in vitro and in vivo using cancer...distribution. This work opens up a new paradigm for synergistic combination of HIFU thermal ablation with heat-induced gene therapy to improve the overall

  1. Schwann cell-specific JAM-C-deficient mice reveal novel expression and functions for JAM-C in peripheral nerves

    Science.gov (United States)

    Colom, Bartomeu; Poitelon, Yannick; Huang, Wenlong; Woodfin, Abigail; Averill, Sharon; Del Carro, Ubaldo; Zambroni, Desirée; Brain, Susan D.; Perretti, Mauro; Ahluwalia, Amrita; Priestley, John V.; Chavakis, Triantafyllos; Imhof, Beat A.; Feltri, M. Laura; Nourshargh, Sussan

    2012-01-01

    Junctional adhesion molecule-C (JAM-C) is an adhesion molecule expressed at junctions between adjacent endothelial and epithelial cells and implicated in multiple inflammatory and vascular responses. In addition, we recently reported on the expression of JAM-C in Schwann cells (SCs) and its importance for the integrity and function of peripheral nerves. To investigate the role of JAM-C in neuronal functions further, mice with a specific deletion of JAM-C in SCs (JAM-C SC KO) were generated. Compared to wild-type (WT) controls, JAM-C SC KO mice showed electrophysiological defects, muscular weakness, and hypersensitivity to mechanical stimuli. In addressing the underlying cause of these defects, nerves from JAM-C SC KO mice were found to have morphological defects in the paranodal region, exhibiting increased nodal length as compared to WTs. The study also reports on previously undetected expressions of JAM-C, namely on perineural cells, and in line with nociception defects of the JAM-C SC KO animals, on finely myelinated sensory nerve fibers. Collectively, the generation and characterization of JAM-C SC KO mice has provided unequivocal evidence for the involvement of SC JAM-C in the fine organization of peripheral nerves and in modulating multiple neuronal responses.—Colom, B., Poitelon, Y., Huang, W., Woodfin, A., Averill, S., Del Carro, U., Zambroni, D., Brain, S. D., Perretti, M., Ahluwalia, A., Priestley, J. V., Chavakis, T., Imhof, B. A., Feltri, M. L., Nourshargh, S. Schwann cell-specific JAM-C-deficient mice reveal novel expression and functions for JAM-C in peripheral nerves. PMID:22090315

  2. Heat induces interleukin-6 in skeletal muscle cells via TRPV1/PKC/CREB pathways.

    Science.gov (United States)

    Obi, Syotaro; Nakajima, Toshiaki; Hasegawa, Takaaki; Kikuchi, Hironobu; Oguri, Gaku; Takahashi, Masao; Nakamura, Fumitaka; Yamasoba, Tatsuya; Sakuma, Masashi; Toyoda, Shigeru; Tei, Chuwa; Inoue, Teruo

    2017-03-01

    Interleukin-6 (IL-6) is released from skeletal muscle cells and induced by exercise, heat, catecholamine, glucose, lipopolysaccharide, reactive oxygen species, and inflammation. However, the mechanism that induces release of IL-6 from skeletal muscle cells remains unknown. Thermosensitive transient receptor potential (TRP) proteins such as TRPV1-4 play vital roles in cellular functions. In this study we hypothesized that TRPV1 senses heat, transmits a signal into the nucleus, and produces IL-6. The purpose of the present study is to investigate the underlying mechanisms whereby skeletal muscle cells sense and respond to heat. When mouse myoblast cells were exposed to 37-42°C for 2 h, mRNA expression of IL-6 increased in a temperature-dependent manner. Heat also increased IL-6 secretion in myoblast cells. A fura 2 fluorescence dual-wavelength excitation method showed that heat increased intracellular calcium flux in a temperature-dependent manner. Intracellular calcium flux and IL-6 mRNA expression were increased by the TRPV1 agonists capsaicin and N-arachidonoyldopamine and decreased by the TRPV1 antagonists AMG9810 and SB366791 and siRNA-mediated knockdown of TRPV1. TRPV2, 3, and 4 agonists did not change intracellular calcium flux. Western blotting with inhibitors demonstrated that heat increased phosphorylation levels of TRPV1, followed by PKC and cAMP response element-binding protein (CREB). PKC inhibitors, Gö6983 and staurosporine, CREB inhibitors, curcumin and naphthol AS-E, and knockdown of CREB suppressed the heat-induced increases in IL-6. These results indicate that heat increases IL-6 in skeletal muscle cells through the TRPV1, PKC, and CREB signal transduction pathway.NEW & NOTEWORTHY Heat increases the release of interleukin-6 (IL-6) from skeletal muscle cells. IL-6 has been shown to serve immune responses and metabolic functions in muscle. It can be anti-inflammatory as well as proinflammatory. However, the mechanism that induces release of IL-6

  3. Heat-killed Staphylococcus aureus reduces atherosclerosis by inducing anti-inflammatory macrophages

    NARCIS (Netherlands)

    Frodermann, V.; van Duijn, J.; van Puijvelde, G. H. M.; van Santbrink, P. J.; Lagraauw, H. M.; de Vries, Margreet R; Quax, P. H. A.; Bot, I.; Foks, A. C.; de Jager, S. C. A.; Kuiper, J.

    Background Staphylococcus aureus cell wall components can induce IL-10 responses by immune cells, which may be atheroprotective. Therefore, in this study, we investigated whether heat-killed S. aureus (HK-SA) could inhibit the development of atherosclerosis. Methods Atherosclerosis-susceptible LDL

  4. Volume analysis of heat-induced cracks in human molars: A preliminary study.

    Science.gov (United States)

    Sandholzer, Michael A; Baron, Katharina; Heimel, Patrick; Metscher, Brian D

    2014-05-01

    Only a few methods have been published dealing with the visualization of heat-induced cracks inside bones and teeth. As a novel approach this study used nondestructive X-ray microtomography (micro-CT) for volume analysis of heat-induced cracks to observe the reaction of human molars to various levels of thermal stress. Eighteen clinically extracted third molars were rehydrated and burned under controlled temperatures (400, 650, and 800°C) using an electric furnace adjusted with a 25°C increase/min. The subsequent high-resolution scans (voxel-size 17.7 μm) were made with a compact micro-CT scanner (SkyScan 1174). In total, 14 scans were automatically segmented with Definiens XD Developer 1.2 and three-dimensional (3D) models were computed with Visage Imaging Amira 5.2.2. The results of the automated segmentation were analyzed with an analysis of variance (ANOVA) and uncorrected post hoc least significant difference (LSD) tests using Statistical Package for Social Sciences (SPSS) 17. A probability level of P models. The macroscopic heat-induced changes observed in this preliminary study correspond with previous observations of unrestored human teeth, yet the current observations also take into account the entire microscopic 3D expansions of heat-induced cracks within the dental hard tissues. Using the same experimental conditions proposed in the literature, this study confirms previous results, adds new observations, and offers new perspectives in the investigation of forensic evidence.

  5. In-car Advice to Reduce Negative Effects of Phantom Jams

    NARCIS (Netherlands)

    Wismans, Luc Johannes Josephus; Suijs, L.C.W.; Krol, L.; van Berkum, Eric C.

    2015-01-01

    Congestion problems result in economic losses and also have serious implications for traffic safety. In the Netherlands, more than 20% of all congestion is recognized as shockwave jams, or so-called phantom traffic jams, and in other countries this type of jam has been recognized as a significant

  6. Development of a heat-shock inducible gene expression system in the red alga Cyanidioschyzon merolae.

    Directory of Open Access Journals (Sweden)

    Nobuko Sumiya

    Full Text Available The cell of the unicellular red alga Cyanidioschyzon merolae contains a single chloroplast and mitochondrion, the division of which is tightly synchronized by a light/dark cycle. The genome content is extremely simple, with a low level of genetic redundancy, in photosynthetic eukaryotes. In addition, transient transformation and stable transformation by homologous recombination have been reported. However, for molecular genetic analyses of phenomena that are essential for cellular growth and survival, inducible gene expression/suppression systems are needed. Here, we report the development of a heat-shock inducible gene expression system in C. merolae. CMJ101C, encoding a small heat shock protein, is transcribed only when cells are exposed to an elevated temperature. Using a superfolder GFP as a reporter protein, the 200-bp upstream region of CMJ101C orf was determined to be the optimal promoter for heat-shock induction. The optimal temperature to induce expression is 50°C, at which C. merolae cells are able to proliferate. At least a 30-min heat shock is required for the expression of a protein of interest and a 60-min heat shock yields the maximum level of protein expression. After the heat shock, the mRNA level decreases rapidly. As an example of the system, the expression of a dominant negative form of chloroplast division DRP5B protein, which has a mutation in the GTPase domain, was induced. Expression of the dominant negative DRP5B resulted in the appearance of aberrant-shaped cells in which two daughter chloroplasts and the cells are still connected by a small DRP5B positive tube-like structure. This result suggests that the dominant negative DRP5B inhibited the final scission of the chloroplast division site, but not the earlier stages of division site constriction. It is also suggested that cell cycle progression is not arrested by the impairment of chloroplast division at the final stage.

  7. Quasi-Coherent Noise Jamming to LFM Radar Based on Pseudo-random Sequence Phase-modulation

    Directory of Open Access Journals (Sweden)

    N. Tai

    2015-12-01

    Full Text Available A novel quasi-coherent noise jamming method is proposed against linear frequency modulation (LFM signal and pulse compression radar. Based on the structure of digital radio frequency memory (DRFM, the jamming signal is acquired by the pseudo-random sequence phase-modulation of sampled radar signal. The characteristic of jamming signal in time domain and frequency domain is analyzed in detail. Results of ambiguity function indicate that the blanket jamming effect along the range direction will be formed when jamming signal passes through the matched filter. By flexible controlling the parameters of interrupted-sampling pulse and pseudo-random sequence, different covering distances and jamming effects will be achieved. When the jamming power is equivalent, this jamming obtains higher process gain compared with non-coherent jamming. The jamming signal enhances the detection threshold and the real target avoids being detected. Simulation results and circuit engineering implementation validate that the jamming signal covers real target effectively.

  8. Shaping micro-clusters via inverse jamming and topographic close-packing of microbombs.

    Science.gov (United States)

    Yu, Seunggun; Cho, Hyesung; Hong, Jun Pyo; Park, Hyunchul; Jolly, Jason Christopher; Kang, Hong Suk; Lee, Jin Hong; Kim, Junsoo; Lee, Seung Hwan; Lee, Albert S; Hong, Soon Man; Park, Cheolmin; Yang, Shu; Koo, Chong Min

    2017-09-28

    Designing topographic clusters is of significant interest, yet it remains challenging as they often lack mobility or deformability. Here we exploit the huge volumetric expansion (up to 3000%) of a new type of building block, thermally expandable microbombs. They consist of a viscoelastic polymeric shell and a volatile gas core, which, within structural confinement, create micro-clusters via inverse jamming and topographical close-packing. Upon heating, microbombs anchored in rigid confinement underwent balloon-like blowing up, allowing for dense clusters via soft interplay between viscoelastic shells. Importantly, the confinement is unyielding against the internal pressure of the microbombs, thereby enabling self-assembled clusters, which can be coupled with topographic inscription to introduce structural hierarchy on the clusters. Our strategy provides densely packed yet ultralight clusters with a variety of complex shapes, cleavages, curvatures, and hierarchy. In turn, these clusters will enrich our ability to explore the assemblies of the ever-increasing range of microparticle systems.Self-assembled systems are normally composed of incompressible building blocks, which constrain their space filling efficiency. Yu et al. show programmable, densely packed clusters using thermally expandable soft microparticles, whereby the self-assembling process is realized via a jamming transition.

  9. Radio frequency induced hyperthermia mediated by dextran stabilized LSMO nanoparticles: in vitro evaluation of heat shock protein response

    Science.gov (United States)

    Bhayani, K. R.; Rajwade, J. M.; Paknikar, K. M.

    2013-01-01

    Dextran stabilized La0.7Sr0.3MnO3 (Dex-LSMO) is an alternative cancer hyperthermia agent holding considerable promise. Here, we have carried out a comparative study on radio frequency (˜264 kHz) induced Dex-LSMO mediated heating and extraneous heating (mimicking generalized hyperthermia) in terms of changes in the morphology, proliferation pattern and induction of heat shock proteins in a human melanoma cell line (A375). Our results clearly show that the cellular effects seen with extraneous heating (60 min at 43 °C) could be reproduced by just six minutes of radio frequency induced Dex-LSMO mediated heating. More importantly, the observed enhanced levels of HSP 70 and 90 (molecular markers of heat shock that trigger favorable immunological reactions) seen with Dex-LSMO mediated heating were comparable to extraneous heating. These results suggest the possible utility of Dex-LSMO as a cancer hyperthermia agent.

  10. Improving moving jam detection performance with V2I communication

    NARCIS (Netherlands)

    Netten, B.D.; Hegyi, A.; Wang, M.; Schakel, W.; Yuan, Y.; Schreiter, T.; Arem, B. van; Leeuwen, C.J. van; Alkim, T.

    2013-01-01

    Dynamax is a road side based system using the SPECIALIST control algorithm and inductive loops. Dynamax field tests showed that moving jams can be effectively resolved by dynamic speed measures [1,5]. This paper focuses on Dynamax In Car, which extends the road side infrastructure with a V2I

  11. FIJI: Fighting Implicit Jamming in 802.11 WLANs

    Science.gov (United States)

    Broustis, Ioannis; Pelechrinis, Konstantinos; Syrivelis, Dimitris; Krishnamurthy, Srikanth V.; Tassiulas, Leandros

    The IEEE 802.11 protocol inherently provides the same long-term throughput to all the clients associated with a given access point (AP). In this paper, we first identify a clever, low-power jamming attack that can take advantage of this behavioral trait: the placement of a low-power jammer in a way that it affects a single legitimate client can cause starvation to all the other clients. In other words, the total throughput provided by the corresponding AP is drastically degraded. To fight against this attack, we design FIJI, a cross-layer anti-jamming system that detects such intelligent jammers and mitigates their impact on network performance. FIJI looks for anomalies in the AP load distribution to efficiently perform jammer detection. It then makes decisions with regards to optimally shaping the traffic such that: (a) the clients that are not explicitly jammed are shielded from experiencing starvation and, (b) the jammed clients receive the maximum possible throughput under the given conditions. We implement FIJI in real hardware; we evaluate its efficacy through experiments on a large-scale indoor testbed, under different traffic scenarios, network densities and jammer locations. Our measurements suggest that FIJI detects such jammers in real-time and alleviates their impact by allocating the available bandwidth in a fair and efficient way.

  12. 21 CFR 150.160 - Fruit preserves and jams.

    Science.gov (United States)

    2010-04-01

    ... fruits in which the weight of each is not less than one-fifth and the weight of apple is not more than... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Fruit preserves and jams. 150.160 Section 150.160... FOR HUMAN CONSUMPTION FRUIT BUTTERS, JELLIES, PRESERVES, AND RELATED PRODUCTS Requirements for...

  13. Quality Evaluation of Jam Formulated from Baobab and Pawpaw Fruits

    African Journals Online (AJOL)

    In this work, possibility of making jam from two underutilized fruits (baobab and pawpaw fruits) known to have high pectin content was investigated. Formulation was made in different proportions (100:0, 0:100, 70:30, 30:70, and 50:50) using both fruits. Granulated sugar solution and acidifying agent (lime) were added to the ...

  14. Cell jammers, GPS jammers, and other jamming devices.

    Science.gov (United States)

    2012-10-15

    We caution consumers that it is against the law to use a cell or GPS jammer or any other type of device that blocks, : jams or interferes with authorized communications, as well as to import, advertise, sell, or ship such a device. The : FCC Enforcem...

  15. The glass and jamming transitions in dense granular matter

    Science.gov (United States)

    Coulais, Corentin; Candelier, Raphaël; Dauchot, Olivier

    2013-06-01

    Everyday life tells us that matter acquires rigidity either when it cools down, like lava flows which turn into solid rocks, or when it is compacted, like tablets simply formed by powder compression. As suggested by these examples, solidification is not the sole privilege of crystals but also happens for disordered media such as glass formers, granular media, foams, emulsions and colloidal suspensions. Fifteen years ago the "Jamming paradigm" emerged to encompass in a unique framework the glass transition and the emergence of yield stress, two challenging issues in modern condensed matter physics. One must realize how bold this proposal was, given that the glass transition is a finite temperature transition governing the dynamical properties of supercooled liquids, while Jamming is essentially a zero temperature, zero external stress and purely geometric transition which occurs when a given packing of particles reaches the maximum compression state above which particles start to overlap. More recently, the observation of remarkable scaling properties on the approach to jamming led to the conjecture that this zero temperature "critical point" could determine the properties of dense particle systems within a region of the parameter space to be determined, which in principle could include thermal and stressed systems. Fifteen years of intense theoretical and experimental work later, what have we learned about Jamming and glassy dynamics? In this paper, we discuss these issues in the light of the experiments we have been conducting with vibrated grains.

  16. A new jamming technique for secrecy in multi-antenna wireless networks

    KAUST Repository

    Bakr, Omar

    2010-06-01

    We consider the problem of secure wireless communication in the presence of an eavesdropper when the transmitter has multiple antennas, using a variation of the recently proposed artificial noise technique. Under this technique, the transmitter sends a pseudo-noise jamming signal to selectively degrade the link to the eavesdropper without affecting the desired receiver. The previous work in the literature focuses on ideal Gaussian signaling for both the desired signal and the noise signal. The main contribution of this paper is to show that the Gaussian signaling model has important limitations and propose an alternative "induced fading" jamming technique that takes some of these limitations into account. Specifically we show that under the Gaussian noise scheme, the eavesdropper is able to recover the desired signal with very low bit error rates when the transmitter is constrained to use constant envelope signaling. Furthermore, we show that an eavesdropper with multiple antennas is able to use simple, blind constant-envelope algorithms to completely remove the Gaussian artificial noise signal and thus defeat the secrecy scheme. We propose an alternative scheme that induces artificial fading in the channel to the eavesdropper, and show that it outperforms the Gaussian noise scheme in the sense of causing higher bit error rates at the eavesdropper and is also more resistant to constant modulus-type algorithms. © 2010 IEEE.

  17. Insights into the Molecular Events That Regulate Heat-Induced Chilling Tolerance in Citrus Fruits.

    Science.gov (United States)

    Lafuente, María T; Establés-Ortíz, Beatriz; González-Candelas, Luis

    2017-01-01

    Low non-freezing temperature may cause chilling injury (CI), which is responsible for external quality deterioration in many chilling-sensitive horticultural crops. Exposure of chilling-sensitive citrus cultivars to non-lethal high-temperature conditioning may increase their chilling tolerance. Very little information is available about the molecular events involved in such tolerance. In this work, the molecular events associated with the low temperature tolerance induced by heating Fortune mandarin, which is very sensitive to chilling, for 3 days at 37°C prior to cold storage is presented. A transcriptomic analysis reveals that heat-conditioning has an important impact favoring the repression of genes in cold-stored fruit, and that long-term heat-induced chilling tolerance is an active process that requires activation of transcription factors involved in transcription initiation and of the WRKY family. The analysis also shows that chilling favors degradation processes, which affect lipids and proteins, and that the protective effect of the heat-conditioning treatment is more likely to be related to the repression of the genes involved in lipid degradation than to the modification of fatty acids unsaturation, which affects membrane permeability. Another major factor associated with the beneficial effect of the heat treatment on reducing CI is the regulation of stress-related proteins. Many of the genes that encoded such proteins are involved in secondary metabolism and in oxidative stress-related processes.

  18. Insights into the Molecular Events That Regulate Heat-Induced Chilling Tolerance in Citrus Fruits

    Directory of Open Access Journals (Sweden)

    María T. Lafuente

    2017-06-01

    Full Text Available Low non-freezing temperature may cause chilling injury (CI, which is responsible for external quality deterioration in many chilling-sensitive horticultural crops. Exposure of chilling-sensitive citrus cultivars to non-lethal high-temperature conditioning may increase their chilling tolerance. Very little information is available about the molecular events involved in such tolerance. In this work, the molecular events associated with the low temperature tolerance induced by heating Fortune mandarin, which is very sensitive to chilling, for 3 days at 37°C prior to cold storage is presented. A transcriptomic analysis reveals that heat-conditioning has an important impact favoring the repression of genes in cold-stored fruit, and that long-term heat-induced chilling tolerance is an active process that requires activation of transcription factors involved in transcription initiation and of the WRKY family. The analysis also shows that chilling favors degradation processes, which affect lipids and proteins, and that the protective effect of the heat-conditioning treatment is more likely to be related to the repression of the genes involved in lipid degradation than to the modification of fatty acids unsaturation, which affects membrane permeability. Another major factor associated with the beneficial effect of the heat treatment on reducing CI is the regulation of stress-related proteins. Many of the genes that encoded such proteins are involved in secondary metabolism and in oxidative stress-related processes.

  19. A model of jam formation in congested traffic

    Science.gov (United States)

    Bunzarova, N. Zh; Pesheva, N. C.; Priezzhev, V. B.; Brankov, J. G.

    2017-12-01

    We study a model of irreversible jam formation in congested vehicular traffic on an open segment of a single-lane road. The vehicles obey a stochastic discrete-time dynamics which is a limiting case of the generalized Totally Asymmetric Simple Exclusion Process. Its characteristic features are: (a) the existing clusters of jammed cars cannot break into parts; (b) when the leading vehicle of a cluster hops to the right, the whole cluster follows it deterministically, and (c) any two clusters of vehicles, occupying consecutive positions on the chain, may become nearest-neighbors and merge irreversibly into a single cluster. The above dynamics was used in a one-dimensional model of irreversible aggregation by Bunzarova and Pesheva [Phys. Rev. E 95, 052105 (2017)]. The model has three stationary non-equilibrium phases, depending on the probabilities of injection (α), ejection (β), and hopping (p) of particles: a many-particle one, MP, a completely jammed phase CF, and a mixed MP+CF phase. An exact expression for the stationary probability P(1) of a completely jammed configuration in the mixed MP+CF phase is obtained. The gap distribution between neighboring clusters of jammed cars at large lengths L of the road is studied. Three regimes of evolution of the width of a single gap are found: (i) growing gaps with length of the order O(L) when β > p; (ii) shrinking gaps with length of the order O(1) when β < p; and (iii) critical gaps at β = p, of the order O(L 1/2). These results are supported by extensive Monte Carlo calculations.

  20. HSP70-Inducible hNIS-IRES-eGFP Reporter Imaging: Response to Heat Shock

    Directory of Open Access Journals (Sweden)

    Jiantu Che

    2007-11-01

    Full Text Available A retroviral vector pQHSP70/hNIS-IRES-eGFP (pQHNIG70 was constructed containing the hNIS-IRES-eGFP dual-reporter genes under the control of an inducible human heat shock protein (HSP70 promoter and RG2-pQHSP70/hNIS-IRES-eGFP (RG2-pQHNIG70 transduced cells were generated. Heat-induced expression of both reporter genes in RG2-pQHNIG70 cells was validated by enhanced green fluorescent protein (eGFP fluorescence-activated cell sorter, in vitro radiotracer assays, and immunoblot and immunocytochemistry. A 2.2- to 6.1-fold (131I−, a 6.1- to 14.4-fold (99mTcO4−, and a 5.1- to 39-fold (fluorescence increase above baseline was observed in response to graded hyperthermia (39–43°C. Increases in eGFP fluorescence and radiotracer uptake were first noted at 6 hours, reached a maximum at 24 hours, and fell toward baseline at 72 hours. A stable ratio of radiotracer uptake to eGFP fluorescence and to heat shock protein (HSP70 protein was demonstrated over a wide range of expression levels, induced by different levels of heating. We also demonstrate that the local application of heat on RG2-pQHNIG70 xenografts can effectively induce hNIS and eGFP gene expression in vivo and that this expression can be efficiently visualized by fluorescence, scintigraphic, and micro–positron emission tomography imaging. Endogenous HSP70 protein and reporter expression was confirmed by postmortem tissue evaluations (immunoblot and immunohistochemistry. The pQHNIG70 reporter system can be used to study stress and drug responses in transduced cells and tissues.

  1. 3D numerical modeling of coupled phenomena in induced processes of heat treatment with malice

    Directory of Open Access Journals (Sweden)

    Triwong Peeteenut

    2008-01-01

    Full Text Available This paper describes a multi-method Malice package for three dimension coupled phenomena in induced processes of heat treatment by an algorithm weakly coupled with the Migen package integral method defining the electromagnetic model and the Flux-Expert package finite element method defining the thermal model. The integral method is well suited to inductive systems undergoing sinusoidal excitation at midrange or high frequency. The unknowns of both models are current density, scalar potential and temperature. Joule power in the electromagnetic model is generated by Eddy currents. It becomes the heat source in the thermal model.

  2. HMF formation and colour change of bitter orange and sweet orange jams during storage

    Directory of Open Access Journals (Sweden)

    Mirela Kopjar

    2010-01-01

    Full Text Available In this work influence of preparation on 5-hydroxymethylfurfural (HMF and colour of bitter orange jams and sweet orange jams was investigated. Samples were prepared without and with treatment of oranges with ascorbic acid in order to investigate the influence on prevention of browning in jams. Samples were stored for 365 days at 4 °C and at room temperature and formation of HMF and colour change during storage were measured. After jam preparation bitter orange jams had higher HMF content than sweet orange jams (231 mg/kg and 58.3 mg/kg, respectively. Treatment of oranges with ascorbic acid increased formation of HMF during preparation of jams (261 mg/kg and 95 mg/kg for bitter and sweet orange jams. During storage the same tendency was observed. Also, difference in colour between sweet and bitter orange jams was observed. The highest colour change was observed in bitter orange jams (ΔE* = 5.66 with addition of ascorbic acid. In this work the importance of pH value of jams and storage temperature for HMF formation and colour was emphasised.

  3. The Effect of Surface Charge Saturation on Heat-induced Aggregation of Firefly Luciferase.

    Science.gov (United States)

    Gharanlar, Jamileh; Hosseinkhani, Saman; Sajedi, Reza H; Yaghmaei, Parichehr

    2015-01-01

    We present here the effect of firefly luciferase surface charge saturation and the presence of some additives on its thermal-induced aggregation. Three mutants of firefly luciferase prepared by introduction of surface Arg residues named as 2R, 3R and 5R have two, three and five additional arginine residues substituted at their surface compared to native luciferase; respectively. Turbidimetric study of heat-induced aggregation indicates that all three mutants were reproducibly aggregated at higher rates relative to wild type in spite of their higher thermostability. Among them, 2R had most evaluated propensity to heat-induced aggregation. Therefore, the hydrophilization followed by appearing of more substituted arginine residues with positive charge on the firefly luciferase surface was not reduced its thermal aggregation. Nevertheless, at the same condition in the presence of charged amino acids, e.g. Arg, Lys and Glu, as well as a hydrophobic amino acid, e.g. Val, the heat-induced aggregation of wild type and mutants of firefly luciferases was markedly decelerated than those in the absence of additives. On the basis of obtained results it seems, relinquishment of variety in charge of amino acid side chains, they via local interactions with proteins cause to decrease rate and extent of their thermal aggregation. © 2015 The American Society of Photobiology.

  4. Inducible Transposition of a Heat-Activated Retrotransposon in Tissue Culture.

    Science.gov (United States)

    Masuta, Yukari; Nozawa, Kosuke; Takagi, Hiroki; Yaegashi, Hiroki; Tanaka, Keisuke; Ito, Tasuku; Saito, Hideyuki; Kobayashi, Hisato; Matsunaga, Wataru; Masuda, Seiji; Kato, Atsushi; Ito, Hidetaka

    2017-02-01

    A transposition of a heat-activated retrotransposon named ONSEN required compromise of a small RNA-mediated epigenetic regulation that includes RNA-directed DNA methylation (RdDM) machinery after heat treatment. In the current study, we analyzed the transcriptional and transpositional activation of ONSEN to better understand the underlying molecular mechanism involved in the maintenance and/or induction of transposon activation in plant tissue culture. We found the transposition of heat-primed ONSEN during tissue culture independently of RdDM mutation. The heat activation of ONSEN transcripts was not significantly up-regulated in tissue culture compared with that in heat-stressed seedlings, indicating that the transposition of ONSEN was regulated independently of the transcript level. RdDM-related genes were up-regulated by heat stress in both tissue culture and seedlings. The level of DNA methylation of ONSEN did not show any change in tissue culture, and the amount of ONSEN-derived small RNAs was not affected by heat stress. The results indicated that the transposition of ONSEN was regulated by an alternative mechanism in addition to the RdDM-mediated epigenetic regulation in tissue culture. We applied the tissue culture-induced transposition of ONSEN to Japanese radish, an important breeding species of the family Brassicaceae. Several new insertions were detected in a regenerated plant derived from heat-stressed tissues and its self-fertilized progeny, revealing the possibility of molecular breeding without genetic modification. © The Author 2016. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  5. Junctional adhesion molecule (JAM-C deficient C57BL/6 mice develop a severe hydrocephalus.

    Directory of Open Access Journals (Sweden)

    Lena Wyss

    Full Text Available The junctional adhesion molecule (JAM-C is a widely expressed adhesion molecule regulating cell adhesion, cell polarity and inflammation. JAM-C expression and function in the central nervous system (CNS has been poorly characterized to date. Here we show that JAM-C(-/- mice backcrossed onto the C57BL/6 genetic background developed a severe hydrocephalus. An in depth immunohistochemical study revealed specific immunostaining for JAM-C in vascular endothelial cells in the CNS parenchyma, the meninges and in the choroid plexus of healthy C57BL/6 mice. Additional JAM-C immunostaining was detected on ependymal cells lining the ventricles and on choroid plexus epithelial cells. Despite the presence of hemorrhages in the brains of JAM-C(-/- mice, our study demonstrates that development of the hydrocephalus was not due to a vascular function of JAM-C as endothelial re-expression of JAM-C failed to rescue the hydrocephalus phenotype of JAM-C(-/- C57BL/6 mice. Evaluation of cerebrospinal fluid (CSF circulation within the ventricular system of JAM-C(-/- mice excluded occlusion of the cerebral aqueduct as the cause of hydrocephalus development but showed the acquisition of a block or reduction of CSF drainage from the lateral to the 3(rd ventricle in JAM-C(-/- C57BL/6 mice. Taken together, our study suggests that JAM-C(-/- C57BL/6 mice model the important role for JAM-C in brain development and CSF homeostasis as recently observed in humans with a loss-of-function mutation in JAM-C.

  6. Junctional adhesion molecule (JAM)-C deficient C57BL/6 mice develop a severe hydrocephalus.

    Science.gov (United States)

    Wyss, Lena; Schäfer, Julia; Liebner, Stefan; Mittelbronn, Michel; Deutsch, Urban; Enzmann, Gaby; Adams, Ralf H; Aurrand-Lions, Michel; Plate, Karl H; Imhof, Beat A; Engelhardt, Britta

    2012-01-01

    The junctional adhesion molecule (JAM)-C is a widely expressed adhesion molecule regulating cell adhesion, cell polarity and inflammation. JAM-C expression and function in the central nervous system (CNS) has been poorly characterized to date. Here we show that JAM-C(-/-) mice backcrossed onto the C57BL/6 genetic background developed a severe hydrocephalus. An in depth immunohistochemical study revealed specific immunostaining for JAM-C in vascular endothelial cells in the CNS parenchyma, the meninges and in the choroid plexus of healthy C57BL/6 mice. Additional JAM-C immunostaining was detected on ependymal cells lining the ventricles and on choroid plexus epithelial cells. Despite the presence of hemorrhages in the brains of JAM-C(-/-) mice, our study demonstrates that development of the hydrocephalus was not due to a vascular function of JAM-C as endothelial re-expression of JAM-C failed to rescue the hydrocephalus phenotype of JAM-C(-/-) C57BL/6 mice. Evaluation of cerebrospinal fluid (CSF) circulation within the ventricular system of JAM-C(-/-) mice excluded occlusion of the cerebral aqueduct as the cause of hydrocephalus development but showed the acquisition of a block or reduction of CSF drainage from the lateral to the 3(rd) ventricle in JAM-C(-/-) C57BL/6 mice. Taken together, our study suggests that JAM-C(-/-) C57BL/6 mice model the important role for JAM-C in brain development and CSF homeostasis as recently observed in humans with a loss-of-function mutation in JAM-C.

  7. Cardiovascular disease-induced thermal responses during passive heat stress: an integrated computational study.

    Science.gov (United States)

    Zhang, Xiancheng; Noda, Shigeho; Himeno, Ryutaro; Liu, Hao

    2016-11-01

    The cardiovascular system plays a crucial role in human thermoregulation; cardiovascular diseases may lead to significantly degrading the thermoregulation ability for patients during exposure to heat stress. To evaluate the thermal responses of patients with common chronic cardiovascular diseases, we here propose an integrated computational model by coupling a two-node thermoregulation model with a closed-loop, multi-compartment, lumped-parameter cardiovascular model. This bioheat transfer model is validated, capable to predict cardiovascular functions and thermal responses under varying environmental conditions. Our results demonstrate that the cardiovascular disease-induced reduction in cardiac output and skin blood flow causes extra elevation in core temperature during hyperthermic challenges. In addition, a combination of aging, obesity, and cardiovascular diseases shows a pronounced increase in core temperature during heat exposure, which implies that such combined effect may increase the risk of heat-related morbidity and mortality. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  8. Local heating induced by single MeV C60 ion impacts

    Science.gov (United States)

    Hayashi, H.; Matsuzaki, S.; Nakajima, K.; Narumi, K.; Saitoh, Y.; Tsujimoto, M.; Toulemonde, M.; Kimura, K.

    2017-09-01

    Gold and platinum nanoparticles of few-nm size were deposited on amorphous silicon oxide and amorphous silicon nitride films. These films were irradiated with 0.72 and 1.1 MeV C603+ ions. Local heating of these films induced by the single ion impact was evaluated by observing desorption of the nanoparticles from the target surfaces upon ion impact. It was found that the local heating at the exit surface is very sensitive to the film thickness. For thinner films, the observed local heating at the exit surface is enhanced compared to the entrance surface while the result is opposite for thicker films. The observed result can be well explained by the unified thermal spike model taking account of the broadening of the spatial distribution of constituent carbon ions during the passage across the film.

  9. Painful tonic heat stimulation induces GABA accumulation in the prefrontal cortex in man

    DEFF Research Database (Denmark)

    Kupers, Ron; Danielsen, Else R; Kehlet, Henrik

    2009-01-01

    Relatively little is known on pain-induced neurotransmitter release in the human cerebral cortex. We used proton magnetic resonance spectroscopy (1H-MRS) during tonic painful heat stimulation to test the hypothesis of increases in both glutamate and GABA, two neurotransmitters with a key role...... in pain processing. Using a 3T MR scanner, we acquired spectra from the rostral anterior cingulate cortex (rACC) in 13 healthy right-handed subjects at rest and during painful heat stimulation. The painful stimulus consisted of a suprathreshold painful tonic heat pulse, which was delivered to the right...... that GABA is released in the human cerebral cortex during painful stimulation. The results are in line with animal findings on the role of GABA in pain processing and with studies in humans showing analgesic efficacy of GABA-related drugs in clinical pain conditions....

  10. Analysis of the beam induced heat loads on the LHC arc beam screens during Run 2

    CERN Document Server

    Iadarola, Giovanni; Dijkstal, Philipp; Mether, Lotta; CERN. Geneva. ATS Department

    2017-01-01

    During Run 2 the Large Hadron Collider (LHC) has been routinely operated with 25 ns bunch spacing. In these conditions large heat loads have been measured on the beam screens of the superconducting magnets, together with other observations indicating that an electron cloud develops in the beam chambers. The analysis of these heat loads has revealed several interesting features allowing to pinpoint peculiar characteristics of the observed beam-induced heating. This document describes the main findings of this analysis including the evolution taking place during the run, the observed dependence on the beam conditions and the results from special tests and dedicated instrumentation. The differences observed in the behavior of the eight LHC arcs are also discussed.

  11. Antimicrobial and inhibition on heat-induced protein denaturation of constituents isolated from Polygonatum verticillatum rhizomes.

    Science.gov (United States)

    Khan, Haroon; Saeed, Muhammad; Rauf, Abdur; Khan, Muhammad Atif; Muhammad, Naveed

    2015-01-01

    This study was designed to assess the susceptibility of various microorganisms and inhibition on heat-induced protein denaturation against diosgenin and santonin, isolated from Polygonatum verticillatum rhizomes. Both diosgenin and santonin showed significant zone of inhibition when studied against various Gram-positive (Bacillus subtilis, Bacillus cereus, Staphylococcus aureus and Staphylococcus epidermidis) and Gram-negative bacteria (Escherichia coli and Salmonella typhi). In antifungal assay, only santonin exhibited profound sensitivity against various fungi (Aspergillus flavus, Aspergillus niger, Trichoderma harzianum and Fusarium oxysporum) used in the test. Both diosgenin and santonin also exhibited marked attenuation on heat-induced protein denaturation in a concentration-dependent manner with EC50 values of 375 and 310 μg/mL, respectively. In conclusion, both the isolated compounds have antimicrobial potential supported by strong inhibition on protein denaturation and thus support the antimicrobial uses of plant in traditional system of treatment.

  12. Heat priming induces trans-generational tolerance to high temperature stress in wheat

    Directory of Open Access Journals (Sweden)

    Xiao eWang

    2016-04-01

    Full Text Available Wheat plants are very sensitive to high temperature stress during grain filling. Effects of heat priming applied to the first generation on tolerance of the successive generation to post-anthesis high temperature stress were investigated. Compared with the progeny of non-heat primed plants (NH, the progeny of heat-primed plants (PH possessed higher grain yield, leaf photosynthesis and activities of antioxidant enzymes and lower cell membrane damage under high temperature stress. In the transcriptome profile, 1430 probes showed obvious difference in expression between PH and NH. These genes were related to signal transduction, transcription, energy, defense, and protein destination and storage, respectively. The gene encoding the lysine-specific histone demethylase 1 (LSD1 which was involved in histone demethylation related to epigenetic modification was up-regulated in the PH compared with NH. The proteome analysis indicated that the proteins involved in photosynthesis, energy production and protein destination and storage were up-regulated in the PH compared with NH. In short, thermos-tolerance was induced through heritable epigenetic alternation and signaling transduction, both processes further triggered prompt modifications of defense related responses in anti-oxidation, transcription, energy production, and protein destination and storage in the progeny of the primed plants under high temperature stress. It was concluded that trans-generation thermo-tolerance was induced by heat priming in the first generation, and this might be an effective measure to cope with severe high-temperature stresses during key growth stages in wheat production.

  13. Influence of Joule heating on current-induced domain wall depinning

    Energy Technology Data Exchange (ETDEWEB)

    Moretti, Simone, E-mail: simone.moretti@usal.es; Raposo, Victor; Martinez, Eduardo [University of Salamanca, Plaza de los Caidos, 37008 Salamanca (Spain)

    2016-06-07

    The domain wall depinning from a notch in a Permalloy nanostrip on top of a SiO{sub 2}/Si substrate is studied theoretically under application of static magnetic fields and the injection of short current pulses. The influence of Joule heating on current-induced domain wall depinning is explored self-consistently by coupling the magnetization dynamics in the ferromagnetic strip to the heat transport throughout the system. Our results indicate that Joule heating plays a remarkable role in these processes, resulting in a reduction in the critical depinning field and/or in a temporary destruction of the ferromagnetic order for typically injected current pulses. In agreement with experimental observations, similar pinning-depinning phase diagrams can be deduced for both current polarities when the Joule heating is taken into account. These observations, which are incompatible with the sole contribution of spin transfer torques, provide a deeper understanding of the physics underlying these processes and establish the real scope of the spin transfer torque. They are also relevant for technological applications based on current-induced domain-wall motion along soft strips.

  14. Light-Induced Local Heating for Thermophoretic Manipulation of DNA in Polymer Micro- and Nanochannels

    DEFF Research Database (Denmark)

    Thamdrup, Lasse Højlund; Larsen, Niels Bent; Kristensen, Anders

    2010-01-01

    We present a method for making polymer chips with a narrow-band near-infrared absorber layer that enables light-induced local heating of liquids inside fluidic micro- and nanochannels fabricated by thermal imprint in polymethyl methacrylate. We have characterized the resulting liquid temperature...... profiles in microchannels using the temperature dependent fluorescence of the complex [Ru(bpy)3]2+. We demonstrate thermophoretic manipulation of individual YOYO-1 stained T4 DNA molecules inside micro- and nanochannels....

  15. Use of a laser-induced fluorescence thermal imaging system for film cooling heat transfer measurement

    Energy Technology Data Exchange (ETDEWEB)

    Chyu, M.K. [Carnegie Mellon Univ., Pittsburgh, PA (United States)

    1995-10-01

    This paper describes a novel approach based on fluorescence imaging of thermographic phosphor that enables the simultaneous determination of both local film effectiveness and local heat transfer on a film-cooled surface. The film cooling model demonstrated consists of a single row of three discrete holes on a flat plate. The transient temperature measurement relies on the temperature-sensitive fluorescent properties of europium-doped lanthanum oxysulfide (La{sub 2}O{sub 2}S:EU{sup 3+}) thermographic phosphor. A series of full-field surface temperatures, mainstream temperatures, and coolant film temperatures were acquired during the heating of a test surface. These temperatures are used to calculate the heat transfer coefficients and the film effectiveness simultaneously. Because of the superior spatial resolution capability for the heat transfer data reduced from these temperature frames, the laser-induced fluorescence (LIF) imaging system, the present study observes the detailed heat transfer characteristics over a film-protected surface. The trend of the results agrees with those obtained using other conventional thermal methods, as well as the liquid crystal imaging technique. One major advantage of this technique is the capability to record a large number of temperature frames over a given testing period. This offers multiple-sample consistency.

  16. Renoprotective effect of virgin coconut oil in heated palm oil diet-induced hypertensive rats.

    Science.gov (United States)

    Kamisah, Yusof; Ang, Shu-Min; Othman, Faizah; Nurul-Iman, Badlishah Sham; Qodriyah, Hj Mohd Saad

    2016-10-01

    Virgin coconut oil, rich in antioxidants, was shown to attenuate hypertension. This study aimed to investigate the effects of virgin coconut oil on blood pressure and related parameters in kidneys in rats fed with 5-times-heated palm oil (5HPO). Thirty-two male Sprague-Dawley rats were divided into 4 groups. Two groups were fed 5HPO (15%) diet and the second group was also given virgin coconut oil (1.42 mL/kg, oral) daily for 16 weeks. The other 2 groups were given basal diet without (control) and with virgin coconut oil. Systolic blood pressure was measured pre- and post-treatment. After 16 weeks, the rats were sacrificed and kidneys were harvested. Dietary 5HPO increased blood pressure, renal thiobarbituric acid reactive substance (TBARS), and nitric oxide contents, but decreased heme oxygenase activity. Virgin coconut oil prevented increase in 5HPO-induced blood pressure and renal nitric oxide content as well as the decrease in renal heme oxygenase activity. The virgin coconut oil also reduced the elevation of renal TBARS induced by the heated oil. However, neither dietary 5HPO nor virgin coconut oil affected renal histomorphometry. In conclusion, virgin coconut oil has a potential to reduce the development of hypertension and renal injury induced by dietary heated oil, possibly via its antioxidant protective effects on the kidneys.

  17. On the existence of motion-induced heat flux due to thermoelastic waves in a one-dimensional solid rod

    Science.gov (United States)

    Semperlotti, Fabio; Sen, Mihir

    2014-03-01

    In this Letter, we show the existence of motion-induced heat transfer in homogeneous isotropic solids due to the propagation of thermoelastic waves. In particular, using the linearized governing equations for thermoelastic waves, we show that heat transfer in a one-dimensional rod is not only due to conduction but also to the local particle displacement a phenomenon which, in principle, is similar to advective heat transfer in fluids. It is found that the time-averaged heat transfer is dependent on both the material properties and the external excitation parameters. This mechanism can potentially be useful in ultrasonic welding and in the development of solid state refrigerators or heat pumps.

  18. Biologically Synthesized Gold Nanoparticles Ameliorate Cold and Heat Stress-Induced Oxidative Stress in Escherichia coli

    Directory of Open Access Journals (Sweden)

    Xi-Feng Zhang

    2016-06-01

    Full Text Available Due to their unique physical, chemical, and optical properties, gold nanoparticles (AuNPs have recently attracted much interest in the field of nanomedicine, especially in the areas of cancer diagnosis and photothermal therapy. Because of the enormous potential of these nanoparticles, various physical, chemical, and biological methods have been adopted for their synthesis. Synthetic antioxidants are dangerous to human health. Thus, the search for effective, nontoxic natural compounds with effective antioxidative properties is essential. Although AuNPs have been studied for use in various biological applications, exploration of AuNPs as antioxidants capable of inhibiting oxidative stress induced by heat and cold stress is still warranted. Therefore, one goal of our study was to produce biocompatible AuNPs using biological methods that are simple, nontoxic, biocompatible, and environmentally friendly. Next, we aimed to assess the antioxidative effect of AuNPs against oxidative stress induced by cold and heat in Escherichia coli, which is a suitable model for stress responses involving AuNPs. The response of aerobically grown E. coli cells to cold and heat stress was found to be similar to the oxidative stress response. Upon exposure to cold and heat stress, the viability and metabolic activity of E. coli was significantly reduced compared to the control. In addition, levels of reactive oxygen species (ROS and malondialdehyde (MDA and leakage of proteins and sugars were significantly elevated, and the levels of lactate dehydrogenase activity (LDH and adenosine triphosphate (ATP significantly lowered compared to in the control. Concomitantly, AuNPs ameliorated cold and heat-induced oxidative stress responses by increasing the expression of antioxidants, including glutathione (GSH, glutathione S-transferase (GST, super oxide dismutase (SOD, and catalase (CAT. These consistent physiology and biochemical data suggest that AuNPs can ameliorate cold and

  19. Yielding and Flow of Soft-Jammed Systems in Elongation

    Science.gov (United States)

    Zhang, X.; Fadoul, O.; Lorenceau, E.; Coussot, P.

    2018-01-01

    So far, yielding and flow properties of soft-jammed systems have only been studied from simple shear and then extrapolated to other flow situations. In particular, simple flows such as elongations have barely been investigated experimentally or only in a nonconstant, partial volume of material. We show that using smooth tool surfaces makes it possible to obtain a prolonged elongational flow over a large range of aspect ratios in the whole volume of material. The normal force measured for various soft-jammed systems with different microstructures shows that the ratio of the elongation yield stress to the shear yield stress is larger (by a factor of around 1.5) than expected from the standard theory which assumes that the stress tensor is a function of the second invariant of the strain rate tensor. This suggests that the constitutive tensor of the materials cannot be determined solely from macroscopic shear measurements.

  20. Security Framework and Jamming Detection for Internet of Things

    DEFF Research Database (Denmark)

    Babar, Sachin D.

    , security for IoT will be a critical concern that must be addressed in order to enable several current and future applications. The resource constrained devices such as cell phones, PDAs, RFIDs, sensor nodes etc. are the part of IoT. Design process for securing these resource constrained devices is guided...... concentrates on embedded security in perspective of software approaches. The IoT system become prone to different security attack, out of all that system is more prone to jamming attack. The goal of research is to design the embedded security framework for IoT and to model the jamming attack and design....../hardware co-design methodology. The security framework for IoT also proposes the AES-GCM-based security protocol. The proposed protocol is divided into two components: first is the creation of capability and second component is an application of AES–GCM. AES-GCM is one of the latest authenticated encryption...

  1. Guava Jam packaging determinant attributes in consumer buying decision

    Directory of Open Access Journals (Sweden)

    Maria Inês Souza Dantas

    2011-09-01

    Full Text Available Using packaging and labels to lure consumers and to communicate product benefits directly on the shelf is a competitive advantage factor in the food industry sector. The label is especially effective since besides supplying basic details, such as weight, ingredients, and instructions in compliance with governmental regulations, it attracts consumers' attention and the desire to buy and which often becomes synonymous to the brand name. The objective of this study was to obtain detailed information on consumers' attitudes, opinions, behavior, and concepts regarding guava jam packaging using the focus group technique. The results showed that label color and design, packaging type and information, and brand name and price are determinant attributes in the consumers' decision to buy guava jam.

  2. Effect of Mantle Rheology on Viscous Heating induced during Ice Sheet Cycles

    Science.gov (United States)

    Huang, Pingping; Wu, Patrick; van der Wal, Wouter

    2017-04-01

    Hanyk et al. (2005) studied the viscous shear heating in the mantle induced by the surface loading and unloading of a parabolic-shaped Laurentide-size ice sheet. They found that for linear rheology, viscous heating is mainly concentrated below the ice sheet. The depth extent of the heating in the mantle is determined by the viscosity distribution. Also, the magnitude of viscous heating is significantly affected by the rate of ice thickness change. However, only one ice sheet has been considered in their work and the interactions between ice sheets and ocean loading have been neglected. Furthermore, only linear rheology has been considered, although they suggested that non-Newtonian rheology may have a stronger effect. Here we follow Hanyk et al. (2005) and computed the viscous dissipation for viscoelastic models using the finite element methodology of Wu (2004) and van der Wal et al. (2010). However, the global ICE6G model (Peltier et al. 2015) with realistic oceans is used here to provide the surface loading. In addition, viscous heating in non-linear rheology, composite rheology, in addition to linear rheology with uniform or VM5a profile are computed and compared. Our results for linear rheology mainly confirm the findings of Hanyk et al. (2005). For both non-linear and composite rheologies, viscous heating is also mainly distributed near and under the ice sheets, but, more concentrated; depending on the horizontal dimension of the ice sheet, it can extend into the lower mantle, but for some of the time, not as deep as that for linear rheology. For composite rheology, the viscous heating is dominated by the effect of non-linear relation between the stress and the strain. The ice history controls the time when the local maximum in viscous heating appears. However, the magnitude of the viscous heating is affected by mantle rheology as well as the ice loading. Due to viscosity stratification, the shape of the region with high viscous heating in model VM5a is a

  3. Earthquake Model Confirms Traffic Jams Caused by Tiredness

    OpenAIRE

    Jarai-Szabo, Ferenc; Neda, Zoltan

    2011-01-01

    A simple one-dimensional spring-block model elaborated for the idealized single-lane highway traffic reveals the causes for the emergence of traffic jams. Based on the stop-time statistics of one car in the row, an order parameter is defined and studied. By extensive computer simulations, the parameter space of the model is explored, analyzed and interpreted. Existence of a free a and congested flow phases is confirmed and the transition between them is analyzed.

  4. Multifrequency OFDM SAR in Presence of Deception Jamming

    OpenAIRE

    Schuerger Jonathan; Garmatyuk Dmitriy

    2010-01-01

    Orthogonal frequency division multiplexing (OFDM) is considered in this paper from the perspective of usage in imaging radar scenarios with deception jamming. OFDM radar signals are inherently multifrequency waveforms, composed of a number of subbands which are orthogonal to each other. While being employed extensively in communications, OFDM has not found comparatively wide use in radar, and, particularly, in synthetic aperture radar (SAR) applications. In this paper, we aim to show the adv...

  5. Fuel Loss and Jams due to Pausing Railroad Crossings

    OpenAIRE

    Tomoeda, Akiyasu; Nishinari, Katsuhiro; Harada, Yoshiaki

    2008-01-01

    In Japan, all cars must pause before crossing the railroad for avoiding the accidents. This rule was established by a law in 1960. In fact, however, railroad crossings come to the serious bottlenecks because of this pausing rule and this bottleneck causes heavy jams. In this study, by using cellular automaton model we have investigated the traffic flow at railroad crossings in two cases: with pausing and without pausing. Moreover, the lost time due to pausing at railroad crossings have been a...

  6. Jamming in Mobile Networks: A Game-Theoretic Approach

    Science.gov (United States)

    2013-03-01

    general treatment of multiplayer differential games was presented by Starr and Ho [16], Leitmann [36], Vaisbord and Zhukovskiy [65], Zhukovskiy and...REPORT Jamming in mobile networks: A game -theoretic approach. 14. ABSTRACT 16. SECURITY CLASSIFICATION OF: In this paper, we address the problem of...model the intrusion as a pursuit-evasion game between a mobile jammer and a team of agents. First, we consider a differential game -theoretic approach

  7. Investigation of drag and heat reduction induced by a novel combinational lateral jet and spike concept in supersonic flows based on conjugate heat transfer approach

    Science.gov (United States)

    Zhu, Liang; Chen, Xiong; Li, Yingkun; Musa, Omer; Zhou, Changsheng

    2018-01-01

    When flying at supersonic or hypersonic speeds through the air, the drag and severe heating have a great impact on the vehicles, thus the drag reduction and thermal protection studies have attracted worldwide attention. In the current study, the Reynolds-averaged Navier-Stokes (RANS) equations coupled with the shear stress transport (SST) k - ω turbulence model have been employed to investigate the flow behavior induced by a novel combinational lateral jet and spike concept in supersonic flows. A coupling conjugate heat transfer (CHT) approach has been applied to investigate the thermal protection, which takes the heat transfer of structure into consideration. After the code was validated by the available experimental results and the gird independency analysis was carried out, the influences of the spike length ratio, lateral jet pressure ratio and lateral jet location on the drag and heat reduction performance are analyzed comprehensively. The obtained results show that a remarkable reduction in the drag and heat flux is achieved when a lateral jet is added to the spike. This implies that the combinational lateral jet and spike concept in supersonic flows have a great benefit to the drag and heat reduction. Both the drag and heat reduction decrease with the increase of the lateral jet pressure ratio, and the heat flux is more sensitive to the lateral jet pressure ratio. The lateral jet should not be located in the bottom of the spike in order to realize better drag and heat reduction performance. The drag and heat flux could be reduced by about 45% by reasonable lateral jet location. The drag decreases with the increase of the spike length ratio whereas the heat flux is affected by the spike length ratio just in a certain range.

  8. Spectroscopic analysis of the role of extractives on heat-induced discoloration of black locust (Robinia pseudoacacia)

    Science.gov (United States)

    Yao Chen; Yongming Fan; Jianmin Gao; Mandla A. Tshabalala; Nicole M. Stark

    2012-01-01

    To investigate the role of extractives on heat-induced discoloration of wood, samples of black locust (Robinia pseudoacacia) wood flour were extracted with various solvents prior to heat-treatment. Analysis of their color parameters and chromophoric structures showed that the chroma value of the unextracted sample decreased while that of the...

  9. EFFECT OF EXPOSURE PROTOCOL AND HEAT SHOCK PROTEIN EXPRESSION ON ARSENITE INDUCED GENOTOXICITY IN MCF-7 BREAST CANCER CELLS

    Science.gov (United States)

    Effect of exposure protocol and heat shock protein expression on arsenite induced genotoxicity in MCF-7 breast cancer cells The genotoxic effects of arsenic (As) are well accepted, yet its mechanism of action is not clearly defined. Heat-shock proteins (HSPs) protect...

  10. Salinization in a stratified aquifer induced by heat transfer from well casings

    Science.gov (United States)

    van Lopik, Jan H.; Hartog, Niels; Zaadnoordijk, Willem Jan; Cirkel, D. Gijsbert; Raoof, Amir

    2015-12-01

    The temperature inside wells used for gas, oil and geothermal energy production, as well as steam injection, is in general significantly higher than the groundwater temperature at shallower depths. While heat loss from these hot wells is known to occur, the extent to which this heat loss may result in density-driven flow and in mixing of surrounding groundwater has not been assessed so far. However, based on the heat and solute effects on density of this arrangement, the induced temperature contrasts in the aquifer due to heat transfer are expected to destabilize the system and result in convection, while existing salt concentration contrasts in an aquifer would act to stabilize the system. To evaluate the degree of impact that may occur under field conditions, free convection in a 50-m-thick aquifer driven by the heat loss from penetrating hot wells was simulated using a 2D axisymmetric SEAWAT model. In particular, the salinization potential of fresh groundwater due to the upward movement of brackish or saline water in a stratified aquifer is studied. To account for a large variety of well applications and configurations, as well as different penetrated aquifer systems, a wide range of well temperatures, from 40 to 100 °C, together with a range of salt concentration (1-35 kg/m3) contrasts were considered. This large temperature difference with the native groundwater (15 °C) required implementation of a non-linear density equation of state in SEAWAT. We show that density-driven groundwater flow results in a considerable salt mass transport (up to 166,000 kg) to the top of the aquifer in the vicinity of the well (radial distance up to 91 m) over a period of 30 years. Sensitivity analysis showed that density-driven groundwater flow and the upward salt transport was particularly enhanced by the increased heat transport from the well into the aquifer by thermal conduction due to increased well casing temperature, thermal conductivity of the soil, as well as decreased

  11. Heat Stress Nephropathy From Exercise-Induced Uric Acid Crystalluria: A Perspective on Mesoamerican Nephropathy.

    Science.gov (United States)

    Roncal-Jimenez, Carlos; García-Trabanino, Ramón; Barregard, Lars; Lanaspa, Miguel A; Wesseling, Catharina; Harra, Tamara; Aragón, Aurora; Grases, Felix; Jarquin, Emmanuel R; González, Marvin A; Weiss, Ilana; Glaser, Jason; Sánchez-Lozada, Laura G; Johnson, Richard J

    2016-01-01

    Mesoamerican nephropathy (MeN), an epidemic in Central America, is a chronic kidney disease of unknown cause. In this article, we argue that MeN may be a uric acid disorder. Individuals at risk for developing the disease are primarily male workers exposed to heat stress and physical exertion that predisposes to recurrent water and volume depletion, often accompanied by urinary concentration and acidification. Uric acid is generated during heat stress, in part consequent to nucleotide release from muscles. We hypothesize that working in the sugarcane fields may result in cyclic uricosuria in which uric acid concentrations exceed solubility, leading to the formation of dihydrate urate crystals and local injury. Consistent with this hypothesis, we present pilot data documenting the common presence of urate crystals in the urine of sugarcane workers from El Salvador. High end-of-workday urinary uric acid concentrations were common in a pilot study, particularly if urine pH was corrected to 7. Hyperuricemia may induce glomerular hypertension, whereas the increased urinary uric acid may directly injure renal tubules. Thus, MeN may result from exercise and heat stress associated with dehydration-induced hyperuricemia and uricosuria. Increased hydration with water and salt, urinary alkalinization, reduction in sugary beverage intake, and inhibitors of uric acid synthesis should be tested for disease prevention. Copyright © 2016 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  12. Internal stress-induced melting below melting temperature at high-rate laser heating

    Science.gov (United States)

    Hwang, Yong Seok; Levitas, Valery I.

    2014-06-01

    In this Letter, continuum thermodynamic and phase field approaches (PFAs) predicted internal stress-induced reduction in melting temperature for laser-irradiated heating of a nanolayer. Internal stresses appear due to thermal strain under constrained conditions and completely relax during melting, producing an additional thermodynamic driving force for melting. Thermodynamic melting temperature for Al reduces from 933.67 K for a stress-free condition down to 898.1 K for uniaxial strain and to 920.8 K for plane strain. Our PFA simulations demonstrated barrierless surface-induced melt nucleation below these temperatures and propagation of two solid-melt interfaces toward each other at the temperatures very close to the corresponding predicted thermodynamic equilibrium temperatures for the heating rate Q ≤1.51×1010K/s. At higher heating rates, kinetic superheating competes with a reduction in melting temperature and melting under uniaxial strain occurs at 902.1 K for Q = 1.51 × 1011 K/s and 936.9 K for Q = 1.46 × 1012 K/s.

  13. Internal stress-induced melting below melting temperature at high-rate laser heating

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Yong Seok, E-mail: yshwang@iastate.edu [Department of Aerospace Engineering, Iowa State University, Ames, Iowa 50011 (United States); Levitas, Valery I., E-mail: vlevitas@iastate.edu [Departments of Aerospace Engineering, Mechanical Engineering, and Material Science and Engineering, Iowa State University, Ames, Iowa 50011 (United States)

    2014-06-30

    In this Letter, continuum thermodynamic and phase field approaches (PFAs) predicted internal stress-induced reduction in melting temperature for laser-irradiated heating of a nanolayer. Internal stresses appear due to thermal strain under constrained conditions and completely relax during melting, producing an additional thermodynamic driving force for melting. Thermodynamic melting temperature for Al reduces from 933.67 K for a stress-free condition down to 898.1 K for uniaxial strain and to 920.8 K for plane strain. Our PFA simulations demonstrated barrierless surface-induced melt nucleation below these temperatures and propagation of two solid-melt interfaces toward each other at the temperatures very close to the corresponding predicted thermodynamic equilibrium temperatures for the heating rate Q≤1.51×10{sup 10}K/s. At higher heating rates, kinetic superheating competes with a reduction in melting temperature and melting under uniaxial strain occurs at 902.1 K for Q = 1.51 × 10{sup 11 }K/s and 936.9 K for Q = 1.46 × 10{sup 12 }K/s.

  14. Heat-induced cross-linking and degradation of wheat gluten, serum albumin, and mixtures thereof.

    Science.gov (United States)

    Rombouts, Ine; Lagrain, Bert; Delcour, Jan A

    2012-10-10

    Some wheat-based food systems, such as cakes, cookies, and egg noodles, contain mixtures of animal and plant (gluten) proteins and are processed under (mildly) alkaline conditions. Although changes in these proteins during processing can affect end product quality, they have seldom been studied. This study investigated protein cross-linking and degradation during heating (0-120 min, pH 8.0, 50-130 °C) of (mixtures of) wheat gluten and bovine serum albumin (BSA). The decrease in protein extractabilities in sodium dodecyl sulfate containing buffer under (non)reducing conditions and the levels of (cross-linked) amino acids were measured. No indications for polymerization at 50 °C were found. Below 100 °C, BSA polymerized more readily than wheat gluten. Above 100 °C, the opposite was observed. The kinetics of heat-induced polymerization of a 1:1 gluten-BSA mixture were similar to that of isolated gluten, implying that gluten decelerated BSA denaturation. Severe heating (130 °C, >15 min) induced degradation reactions in gluten but not in BSA. At all conditions used in this study, disulfide (SS) bonds contributed to the extractability loss. In addition, above 110 °C, β-elimination of cystine led to non-SS cross-links. Intramolecular SS bonds more often transformed in intermolecular non-SS bonds in BSA than in gluten.

  15. Aloin Protects Skin Fibroblasts from Heat Stress-Induced Oxidative Stress Damage by Regulating the Oxidative Defense System.

    Directory of Open Access Journals (Sweden)

    Fu-Wei Liu

    Full Text Available Oxidative stress is commonly involved in the pathogenesis of skin damage induced by environmental factors, such as heat stress. Skin fibroblasts are responsible for the connective tissue regeneration and the skin recovery from injury. Aloin, a bioactive compound in Aloe vera, has been reported to have various pharmacological activities, such as anti-inflammatory effects. The aim of this study was to investigate the protective effect of aloin against heat stress-mediated oxidative stress in human skin fibroblast Hs68 cells. Hs68 cells were first incubated at 43°C for 30 min to mimic heat stress. The study was further examined if aloin has any effect on heat stress-induced oxidative stress. We found that aloin protected Hs68 cells against heat stress-induced damage, as assessed by 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide and lactate dehydrogenase assay. Aloin protected Hs68 cells by regulating reactive oxygen species production and increasing the levels of glutathione, cytosolic and mitochondrial superoxide dismutase. Aloin also prevented the elevation of thiobarbituric acid reactive substances and the reduction of 8-OH-dG induced by heat stress. These results indicated that aloin protected human skin fibroblasts from heat stress-induced oxidative stress damage by regulating the oxidative defense system.

  16. Aloin Protects Skin Fibroblasts from Heat Stress-Induced Oxidative Stress Damage by Regulating the Oxidative Defense System.

    Science.gov (United States)

    Liu, Fu-Wei; Liu, Fu-Chao; Wang, Yu-Ren; Tsai, Hsin-I; Yu, Huang-Ping

    2015-01-01

    Oxidative stress is commonly involved in the pathogenesis of skin damage induced by environmental factors, such as heat stress. Skin fibroblasts are responsible for the connective tissue regeneration and the skin recovery from injury. Aloin, a bioactive compound in Aloe vera, has been reported to have various pharmacological activities, such as anti-inflammatory effects. The aim of this study was to investigate the protective effect of aloin against heat stress-mediated oxidative stress in human skin fibroblast Hs68 cells. Hs68 cells were first incubated at 43°C for 30 min to mimic heat stress. The study was further examined if aloin has any effect on heat stress-induced oxidative stress. We found that aloin protected Hs68 cells against heat stress-induced damage, as assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and lactate dehydrogenase assay. Aloin protected Hs68 cells by regulating reactive oxygen species production and increasing the levels of glutathione, cytosolic and mitochondrial superoxide dismutase. Aloin also prevented the elevation of thiobarbituric acid reactive substances and the reduction of 8-OH-dG induced by heat stress. These results indicated that aloin protected human skin fibroblasts from heat stress-induced oxidative stress damage by regulating the oxidative defense system.

  17. Heterogeneously Nd(3+) doped single nanoparticles for NIR-induced heat conversion, luminescence, and thermometry.

    Science.gov (United States)

    Marciniak, Lukasz; Pilch, Aleksandra; Arabasz, Sebastian; Jin, Dayong; Bednarkiewicz, Artur

    2017-06-22

    The current frontier in nanomaterials engineering is to intentionally design and fabricate heterogeneous nanoparticles with desirable morphology and composition, and to integrate multiple functionalities through highly controlled epitaxial growth. Here we show that heterogeneous doping of Nd(3+) ions following a core-shell design already allows three optical functions, namely efficient (η > 72%) light-to-heat conversion, bright NIR emission, and sensitive (SR > 0.1% K(-1)) localized temperature quantification, to be built within a single ca. 25 nm nanoparticle. Importantly, all these optical functions operate within the transparent biological window of the NIR spectral region (λexc ∼ 800 nm, λemi ∼ 860 nm), in which light scattering and absorption by tissues and water are minimal. We find NaNdF4 as a core is efficient in absorbing and converting 808 nm light to heat, while NaYF4:1%Nd(3+) as a shell is a temperature sensor based on the ratio-metric luminescence reading but an intermediate inert spacer shell, e.g. NaYF4, is necessary to insulate the heat convertor and thermometer by preventing the possible Nd-Nd energy relaxation. Moreover, we notice that while temperature sensitivity and luminescence intensity are optically stable, increased excitation intensity to generate heat above room temperature may saturate the sensing capacity of temperature feedback. We therefore propose a dual beam photoexcitation scheme as a solution for possible light-induced hyperthermia treatment.

  18. Heat-induced symmetry breaking in ant (Hymenoptera: Formicidae escape behavior.

    Directory of Open Access Journals (Sweden)

    Yuan-Kai Chung

    Full Text Available The collective egress of social insects is important in dangerous situations such as natural disasters or enemy attacks. Some studies have described the phenomenon of symmetry breaking in ants, with two exits induced by a repellent. However, whether symmetry breaking occurs under high temperature conditions, which are a common abiotic stress, remains unknown. In our study, we deposited a group of Polyrhachis dives ants on a heated platform and counted the number of escaping ants with two identical exits. We discovered that ants asymmetrically escaped through two exits when the temperature of the heated platform was >32.75°C. The degree of asymmetry increased linearly with the temperature of the platform. Furthermore, the higher the temperature of heated platform was, the more ants escaped from the heated platform. However, the number of escaping ants decreased for 3 min when the temperature was higher than the critical thermal limit (39.46°C, which is the threshold for ants to endure high temperature without a loss of performance. Moreover, the ants tended to form small groups to escape from the thermal stress. A preparatory formation of ant grouping was observed before they reached the exit, indicating that the ants actively clustered rather than accidentally gathered at the exits to escape. We suggest that a combination of individual and grouping ants may help to optimize the likelihood of survival during evacuation.

  19. Reversible Heat-Induced Inactivation of Chimeric β-Glucuronidase in Transgenic Plants1

    Science.gov (United States)

    Almoguera, Concepción; Rojas, Anabel; Jordano, Juan

    2002-01-01

    We compared the expression patterns in transgenic tobacco (Nicotiana tabacum) of two chimeric genes: a translational fusion to β-glucuronidase (GUS) and a transcriptional fusion, both with the same promoter and 5′-flanking sequences of Ha hsp17.7 G4, a small heat shock protein (sHSP) gene from sunflower (Helianthus annuus). We found that immediately after heat shock, the induced expression from the two fusions in seedlings was similar, considering chimeric mRNA or GUS protein accumulation. Surprisingly, we discovered that the chimeric GUS protein encoded by the translational fusion was mostly inactive in such conditions. We also found that this inactivation was fully reversible. Thus, after returning to control temperature, the GUS activity was fully recovered without substantial changes in GUS protein accumulation. In contrast, we did not find differences in the in vitro heat inactivation of the respective GUS proteins. Insolubilization of the chimeric GUS protein correlated with its inactivation, as indicated by immunoprecipitation analyses. The inclusion in another chimeric gene of the 21 amino-terminal amino acids from a different sHSP lead to a comparable reversible inactivation. That effect not only illustrates unexpected post-translational problems, but may also point to sequences involved in interactions specific to sHSPs and in vivo heat stress conditions. PMID:12011363

  20. Evaluation of induced activity, decay heat and dose rate distribution after shutdown in ITER

    Energy Technology Data Exchange (ETDEWEB)

    Maki, Koichi [Hitachi Ltd., Ibaraki (Japan). Hitachi Research Lab.; Satoh, Satoshi; Hayashi, Katsumi; Yamada, Koubun; Takatsu, Hideyuki; Iida, Hiromasa

    1997-03-01

    Induced activity, decay heat and dose rate distributions after shutdown were estimated for 1MWa/m{sup 2} operation in ITER. The activity in the inboard blanket one day after shutdown is 1.5x10{sup 11}Bq/cm{sup 3}, and the average decay heating rate 0.01w/cm{sup 3}. The dose rate outside the 120cm thick concrete biological shield is two order higher than the design criterion of 5{mu}Sv/h. This indicates that the biological shield thickness should be enhanced by 50cm in concrete, that is, total thickness 170cm for workers to enter the reactor room and to perform maintenance. (author)

  1. Nanoimprinted polymer chips for light induced local heating of liquids in micro- and nanochannels

    DEFF Research Database (Denmark)

    Thamdrup, Lasse Højlund; Pedersen, Jonas Nyvold; Flyvbjerg, Henrik

    2010-01-01

    A nanoimprinted polymer chip with a thin near-infrared absorber layer that enables light-induced local heating (LILH) of liquids inside micro- and nanochannels is presented. An infrared laser spot and corresponding hot-spot could be scanned across the device. Large temperature gradients yield...... thermophoretic forces, which are used to manipulate and stretch individual DNA molecules confined in nanochannels. The absorber layer consists of a commercially available phthalocyanine dye (Fujifilm), with a narrow absorption peak at approximately 775 nm, dissolved in SU-8 photoresist (Microchem Corp.). The 500...... a 785 nm laser diode was focused from the backside of the chip to a spot diameter down to 5 ..m in the absorber layer, yielding a localized heating (Gaussian profile) and large temperature gradients in the liquid in the nanochannels. A laser power of 38 mW yielded a temperature of 40°C in the center...

  2. Heat stress induced changes in metabolic regulators of donkeys from arid tracts in India

    Directory of Open Access Journals (Sweden)

    Kataria N.

    2012-05-01

    Full Text Available To find out heat stress induced changes in metabolic regulators of donkeys from arid tracts in India, blood samples were collected to harvest the serum during moderate and extreme hot ambiences. The metabolic enzymes determined were sorbitol dehydrogenase, malate dehydrogenase, glucose-6-phosphate dehydrogenase, glutamate dehydrogenase, ornithine carbamoyl transferase, gammaglutamayl transferase, 5’nucleotidase, glucose-6-phosphatase, arginase, and aldolase. The mean values of all the serum enzymes increased significantly (p≤0.05 during hot ambience as compared to respective values during moderate ambience. It was concluded that increased activity of all the enzymes in the serum was due to modulation of metabolic reactions to combat the effect of hot ambience on the animals. Activation of gluconeogenesis along with hexose monophosphate shunt and urea cycle probably helped the animals to combat the heat stress.

  3. Formation of tRNA granules in the nucleus of heat-induced human cells

    Energy Technology Data Exchange (ETDEWEB)

    Miyagawa, Ryu [Radioisotope Center, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-0032 (Japan); Department of Biological Science, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8654 (Japan); Mizuno, Rie [Radioisotope Center, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-0032 (Japan); Watanabe, Kazunori, E-mail: watanabe@ric.u-tokyo.ac.jp [Radioisotope Center, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-0032 (Japan); Ijiri, Kenichi [Radioisotope Center, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-0032 (Japan); Department of Biological Science, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8654 (Japan)

    2012-02-03

    Highlights: Black-Right-Pointing-Pointer tRNAs are tranlocated into the nucleus in heat-induced HeLa cells. Black-Right-Pointing-Pointer tRNAs form the unique granules in the nucleus. Black-Right-Pointing-Pointer tRNA ganules overlap with nuclear stress granules. -- Abstract: The stress response, which can trigger various physiological phenomena, is important for living organisms. For instance, a number of stress-induced granules such as P-body and stress granule have been identified. These granules are formed in the cytoplasm under stress conditions and are associated with translational inhibition and mRNA decay. In the nucleus, there is a focus named nuclear stress body (nSB) that distinguishes these structures from cytoplasmic stress granules. Many splicing factors and long non-coding RNA species localize in nSBs as a result of stress. Indeed, tRNAs respond to several kinds of stress such as heat, oxidation or starvation. Although nuclear accumulation of tRNAs occurs in starved Saccharomyces cerevisiae, this phenomenon is not found in mammalian cells. We observed that initiator tRNA{sup Met} (Meti) is actively translocated into the nucleus of human cells under heat stress. During this study, we identified unique granules of Meti that overlapped with nSBs. Similarly, elongator tRNA{sup Met} was translocated into the nucleus and formed granules during heat stress. Formation of tRNA granules is closely related to the translocation ratio. Then, all tRNAs may form the specific granules.

  4. Increased brain L-arginine availability facilitates cutaneous heat loss induced by running exercise.

    Science.gov (United States)

    Wanner, Samuel Penna; Leite, Laura Hora Rios; Guimarães, Juliana Bohnen; Coimbra, Cândido Celso

    2015-06-01

    The effects of increased brain availability of L-arginine (L-arg), a precursor for nitric oxide synthesis, on core body temperature (Tcore ) and cutaneous heat loss were evaluated in running rats. One week prior to the experiments, adult male Wistar rats received the following implants: a chronic guide cannula in the lateral cerebral ventricle and a temperature sensor in the abdominal cavity. On the day of the experiments, the rats were assigned to receive a 2-μL intracerebroventricular injection of either NaCl (0.15 mol/L) or L-arg solution (0.825, 1.65 or 3.30 mol/L); Tcore and tail skin temperature were measured while the rats ran at a speed of 18 m/min until they were fatigued. L-arginine induced a dose-dependent reduction in the threshold Tcore required for cutaneous heat loss (38.09 ± 0.20°C for 3.30-mol/L L-arg vs 38.61 ± 0.10°C for saline; P exercise-induced hyperthermia. Although the rats treated with L-arg presented a lower Tcore at the end of exercise (~0.7°C lower after treatment with the highest dose), no changes in the time to fatigue were observed relative to the control trial. These results suggest that brain L-arg controls heat loss during exercise, most likely by modulating the sympathetic vasoconstrictor tonus to skin vessels. Furthermore, despite facilitating cutaneous heat loss mechanisms, increased brain L-arg availability did not enhance physical performance. © 2015 Wiley Publishing Asia Pty Ltd.

  5. Environmental Heat and Salt Stress Induce Transgenerational Phenotypic Changes in Arabidopsis thaliana

    Science.gov (United States)

    Suter, Léonie; Widmer, Alex

    2013-01-01

    Plants that can adapt their phenotype may be more likely to survive changing environmental conditions. Heritable epigenetic variation could provide a way to rapidly adapt to such changes. Here we tested whether environmental stress induces heritable, potentially adaptive phenotypic changes independent of genetic variation over few generations in Arabidopsis thaliana. We grew two accessions (Col-0, Sha-0) of A. thaliana for three generations under salt, heat and control conditions and tested for induced heritable phenotypic changes in the fourth generation (G4) and in reciprocal F1 hybrids generated in generation three. Using these crosses we further tested whether phenotypic changes were maternally or paternally transmitted. In generation five (G5), we assessed whether phenotypic effects persisted over two generations in the absence of stress. We found that exposure to heat stress in previous generations accelerated flowering under G4 control conditions in Sha-0, but heritable effects disappeared in G5 after two generations without stress exposure. Previous exposure to salt stress increased salt tolerance in one of two reciprocal F1 hybrids. Transgenerational effects were maternally and paternally inherited. Lacking genetic variability, maternal and paternal inheritance and reversibility of transgenerational effects together indicate that stress can induce heritable, potentially adaptive phenotypic changes, probably through epigenetic mechanisms. These effects were strongly dependent on plant genotype and may not be a general response to stress in A. thaliana. PMID:23585834

  6. Jasmonic acid is a crucial signal transducer in heat shock induced sesquiterpene formation in Aquilaria sinensis

    Science.gov (United States)

    Xu, Yan-Hong; Liao, Yong-Cui; Zhang, Zheng; Liu, Juan; Sun, Pei-Wen; Gao, Zhi-Hui; Sui, Chun; Wei, Jian-He

    2016-01-01

    Agarwood, a highly valuable resinous and fragrant heartwood of Aquilaria plants, is widely used in traditional medicines, incense and perfume. Only when Aquilaria trees are wounded by external stimuli do they form agarwood sesquiterpene defensive compounds. Therefore, understanding the signaling pathway of wound-induced agarwood formation is important. Jasmonic acid (JA) is a well-characterized molecule that mediates a plant’s defense response and secondary metabolism. However, little is known about the function of endogenous JA in agarwood sesquiterpene biosynthesis. Here, we report that heat shock can up-regulate the expression of genes in JA signaling pathway, induce JA production and the accumulation of agarwood sesquiterpene in A. sinensis cell suspension cultures. A specific inhibitor of JA, nordihydroguaiaretic acid (NDGA), could block the JA signaling pathway and reduce the accumulation of sesquiterpene compounds. Additionally, compared to SA and H2O2, exogenously supplied methyl jasmonate has the strongest stimulation effect on the production of sesquiterpene compounds. These results clearly demonstrate the central induction role of JA in heat-shock-induced sesquiterpene production in A. sinensis. PMID:26902148

  7. Radio frequency heating induced edge plasma convection: self-consistent simulations and experiments on ASDEX Upgrade

    Science.gov (United States)

    Zhang, W.; Tierens, W.; Noterdaeme, J.-M.; Bobkov, V.; Aguiam, D.; Coster, D.; Fuenfgelder, H.; Jacquot, J.; Ochoukov, R.; Silva, A.; Colas, L.; Křivská, A.; the ASDEX Upgrade Team; the MST1 Team

    2017-11-01

    Plasma heating with waves in the ion cyclotron range of frequency (ICRF) affects the edge plasma and the edge plasma affects the ICRF heating. In simulations, these nonlinear ICRF—edge plasma interactions have been self-consistently simulated by running the EMC3-EIRENE, RAPLICASOL and SSWICH codes in an iterative way on ASDEX Upgrade for the first time. In experiments, the edge plasma convection induced by powered 3-strap antennas is measured with the antenna embedded reflectometers for the first time. Both the simulation and experimental results indicate that the ICRF induced convective cells are most significant on the top and bottom of the antennas; the edge plasma convection induced by 3-strap antennas in optimized antenna feeding configuration (dipole phasing, power ratio between the center and outer straps ~1.5) is smallest among the studied cases. The simulation results also suggest that compared to the 2-strap antennas, the 3-strap antennas can significantly reduce the plasma convection associated with the radio-frequency sheaths, even with unfavorable power balance between the straps in dipole phasing.

  8. KARAKTERISTIK MIKROKAPSUL Lactobacillus plantarum DAN STABILITASNYA DALAM PRODUK SELAI SALAK [Microcapsule Characteristics of Lactobacillus plantarum and Stability in Snake Fruit Jam

    Directory of Open Access Journals (Sweden)

    Nurwulan Purnasari

    2015-07-01

    Full Text Available Microencapsulation a technique that can be used to improve the viability of probiotic during food processing and through the intestinal tract. Two probiotic candidates (Lb. plantarum BSL and Lb. plantarum 2C12 were encapsulated using 3% sodium alginate and soybean oil (0.2% Tween 80. The objectives of the study were to evaluate the effectivity of microencapsulation technique by emulsion method on the probiotic survival, heat resistance, injured cell, and tolerance to bile salt (0.5% and low pH (pH 2. The encapsulated probiotics were then incorporated into snake fruit jam and evaluated for their viability during storage in room temperature for 4 weeks. The results showed that both microencapsulated probiotics demonstrated good survival with high viability (11 Log CFU g-1. Heat resistance of the encapsulated strains at 50ºC was better than their free cells, although higher temperatures (60-70ºC would lowered the number of survivors. Heating at 50-70ºC caused injury to all probiotics cells either free or encapsulated. The survival of all encapsulated probiotics to bile salt and low pH were also better than their free cells. Encapsulated probiotic bacteria in snake fruit jam showed good viability throughout the four weeks of storage, whereas the free probiotic lost all their viability within two weeks. The total yeast and mold count of the probiotic snake fruit jam at 4 week-storage it was still approximately below the maximum standard. The results suggested that microencapsulation of probiotic by emulsion method is suitable to develop snake fruit jam as fruit based probiotic product.

  9. Evaluation of electronic jamming effect based on seeker captive flight test and missile flight simulation

    Science.gov (United States)

    Gao, Wei; Tie, Weitao

    2017-01-01

    In order to test and evaluate the jamming effect of electronic warfare weapons on missiles, a method based on seeker captive flight jamming test and missile flight simulation test is put forward, in which real data for the jamming effect of the electronic warfare weapon on seekers is obtained by seeker captive flight jamming test, and immitted into a missile digital simulation system to perform large numbers of missile flight simulation tests under jamming, then one could evaluate the jamming effect of the electronic warfare weapon on missiles according to the simulation test results. The method is demonstrated and validated by test and evaluation of the jamming effect of a smokescreen jamming device on TV guidance missiles. The results show that, the method proposed here not only overcomes the shortcomings of both pure digital simulation test and field test, but also combines their advantages, thus could be taken as an easy, economical and reliable method for testing and evaluating electronic jamming effect on missiles.

  10. Using Remote Sensing Data to Parameterize Ice Jam Modeling for a Northern Inland Delta

    Directory of Open Access Journals (Sweden)

    Fan Zhang

    2017-04-01

    Full Text Available The Slave River is a northern river in Canada, with ice being an important component of its flow regime for at least half of the year. During the spring breakup period, ice jams and ice-jam flooding can occur in the Slave River Delta, which is of benefit for the replenishment of moisture and sediment required to maintain the ecological integrity of the delta. To better understand the ice jam processes that lead to flooding, as well as the replenishment of the delta, the one-dimensional hydraulic river ice model RIVICE was implemented to simulate and explore ice jam formation in the Slave River Delta. Incoming ice volume, a crucial input parameter for RIVICE, was determined by the novel approach of using MODIS space-born remote sensing imagery. Space-borne and air-borne remote sensing data were used to parameterize the upstream ice volume available for ice jamming. Gauged data was used to complement modeling calibration and validation. HEC-RAS, another one-dimensional hydrodynamic model, was used to determine ice volumes required for equilibrium jams and the upper limit of ice volume that a jam can sustain, as well as being used as a threshold for the volumes estimated by the dynamic ice jam simulations using RIVICE. Parameter sensitivity analysis shows that morphological and hydraulic properties have great impacts on the ice jam length and water depth in the Slave River Delta.

  11. Correlation between platinum nanoparticle surface rearrangement induced by heat treatment and activity for an oxygen reduction reaction.

    Science.gov (United States)

    Chung, Dong Young; Chung, Young-Hoon; Jung, Namgee; Choi, Kwang-Hyun; Sung, Yung-Eun

    2013-08-28

    Heat treatment of nanoparticles could induce the surface rearrangement for more stable facet exposure induced by thermodynamics. By changing the heat treatment environment, we confirmed the correlation between the oxygen reduction activity and the effect of surface oxide and the degree of surface rearrangement of Pt nanoparticles. Native surface oxide was not a critical factor for oxygen reduction activity. However, the degree of surface rearrangement could affect the activity, which was confirmed by the surface sensitive techniques such as CO(ad) oxidation and potential of zero total charge. Analysis indicated that the driving force for nanoparticle surface rearrangement was affected by the heat treatment environment such as gas, in our case.

  12. Surface properties of heat-induced soluble soy protein aggregates of different molecular masses.

    Science.gov (United States)

    Guo, Fengxian; Xiong, Youling L; Qin, Fang; Jian, Huajun; Huang, Xiaolin; Chen, Jie

    2015-02-01

    Suspensions (2% and 5%, w/v) of soy protein isolate (SPI) were heated at 80, 90, or 100 °C for different time periods to produce soluble aggregates of different molecular sizes to investigate the relationship between particle size and surface properties (emulsions and foams). Soluble aggregates generated in these model systems were characterized by gel permeation chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Heat treatment increased surface hydrophobicity, induced SPI aggregation via hydrophobic interaction and disulfide bonds, and formed soluble aggregates of different sizes. Heating of 5% SPI always promoted large-size aggregate (LA; >1000 kDa) formation irrespective of temperature, whereas the aggregate size distribution in 2% SPI was temperature dependent: the LA fraction progressively rose with temperature (80→90→100 °C), corresponding to the attenuation of medium-size aggregates (MA; 670 to 1000 kDa) initially abundant at 80 °C. Heated SPI with abundant LA (>50%) promoted foam stability. LA also exhibited excellent emulsifying activity and stabilized emulsions by promoting the formation of small oil droplets covered with a thick interfacial protein layer. However, despite a similar influence on emulsion stability, MA enhanced foaming capacity but were less capable of stabilizing emulsions than LA. The functionality variation between heated SPI samples is clearly related to the distribution of aggregates that differ in molecular size and surface activity. The findings may encourage further research to develop functional SPI aggregates for various commercial applications. © 2015 Institute of Food Technologists®

  13. A spread spectrum system with frequency hopping and sequentially balanced modulation. II - Operation in jamming and multipath

    Science.gov (United States)

    Mathis, R. F.; Pawula, R. F.

    1980-10-01

    The performance of a spread spectrum system which incorporates frequency hopping, sequentially balanced modulation, phase-comparison tone ranging, and pseudoorthogonal block coding of BPSK data with maximum likelihood of soft decision decoding, is evaluated in jamming environments and multipath. The jamming models considered include partial-band noise jamming, comb-type partial-band noise jamming, multitone jamming, and comb-type multitone jamming. Specular multipath with broad-band noise are shown to be the most serious form of interference. Bit-error probability and ranging accuracy curves are presented.

  14. Heat generation above break-even from laser-induced fusion in ultra-dense deuterium

    OpenAIRE

    Leif Holmlid

    2015-01-01

    Previous results from laser-induced processes in ultra-dense deuterium D(0) give conclusive evidence for ejection of neutral massive particles with energy >10 MeV u−1. Such particles can only be formed from nuclear processes like nuclear fusion at the low laser intensity used. Heat generation is of interest for future fusion energy applications and has now been measured by a small copper (Cu) cylinder surrounding the laser target. The temperature rise of the Cu cylinder is measured with an NT...

  15. Technical solutions to prevent heat stress induced crop growth reduction for three climatic regions in Mexico

    OpenAIRE

    Ooster, van 't, A.; Heuvelink, E.; Loaiza Mejia, V.M.; Henten, van, E.J.

    2008-01-01

    In the last 15 years a significant increase in greenhouse area has occurred in Mexico, from a modest 50 hectares in 1990 to over 2,000 hectares in 2004. The rapid increase in greenhouse area is a result of an attractive export market, USA. Mexican summer midday temperatures are well above crop optimum and cooling is needed if heat stress induced crop growth reduction is to be prevented. The objective of this study was to determine the effectiveness and feasibility of greenhouse cooling system...

  16. HEAT INDUCIBLE EXPRESSION OF ANTIFREEZE PROTEIN GENES FROM THE BEETLES Tenebrio molitor AND Microdera punctipennis.

    Science.gov (United States)

    Li, Jieqiong; Ma, Wenjing; Ma, Ji

    2016-01-01

    Antifreeze proteins (AFPs) play important roles in protecting poikilothermic organisms from cold damage. The expression of AFP genes (afps) is induced by low temperature. However, it is reported that heat can influence the expression of afps in the desert beetle Microdera punctipennis. To further detect whether heat also induce the expression of afps in other insects, and to determine the expression profiling of insect afps at different temperatures. The expression of antifreeze protein genes in the two beetles, Microdera punctipennis and Tenebrio molitor that have quite different living environment, under different temperatures were studied by using real-time quantitative PCR. Mild low temperatures (5~15 degree C), high temperature (38~47 degree C for M. punctipennis, or 37~42 degree C for T. molitor) and temperature difference (10~30 degree C) all stimulated strongly to the expression of AFP genes (Mpafps) in M. punctipennis which lives in the wild filed in desert. The mRNA level of Mpafps after M. punctipennis were exposed to these temperatures for 1h~5h was at least 30-fold of the control at 25 degree C. For T. molitor which is breeding in door with wheat bran all these temperatures stimulated significantly to the expression of Tmafps, while the extent and degree of the temperature stimulation on Tmafps expression were much lower than on Mpafps. After T. molitor were exposed to 5 degree C and 15 degree C for 1h~5h, the mRNA level of Tmafps was over 6-fold and 45-fold of the control at 25 degree C. High temperature (37~42 degree C) for 1h~3h treatments increased Tmafps mRNA level 4.8-fold of the control. Temperature difference of 10 degree C was effective in stimulating Tmafps expression. The expression of insect antifreeze protein genes both in M. punctipennis and T. molitor was induced by heat, suggesting that this phenomenon may be common in insects; the extent and degree of the influence differ in species that have different living conditions. The heat

  17. Erythromycin inhibits tumor necrosis factor alpha and interleukin 6 production induced by heat-killed Streptococcus pneumoniae in whole blood

    NARCIS (Netherlands)

    Schultz, M. J.; Speelman, P.; Zaat, S.; van Deventer, S. J.; van der Poll, T.

    1998-01-01

    To determine the effects of penicillin and erythromycin on cytokine production induced by heat-killed Streptococcus pneumoniae (HKSP), we studied the effects of those drugs on cytokine production induced by S. pneumoniae in human whole blood in vitro and ex vivo. In whole blood in vitro,

  18. Changes in viscosity behavior from a normal organogelator to a heat-induced gelator for a long-chain amidoamine derivative.

    Science.gov (United States)

    Morita, Clara; Sugimoto, Hiroki; Matsue, Keisuke; Kondo, Takeshi; Imura, Yoshiro; Kawai, Takeshi

    2010-11-14

    A long-chain amidoamine derivative (C18AA) acts as a normal organogelator in toluene, but changes to a heat-induced gelator, exhibiting a phase transition from sol to gel on heating upon addition of aqueous LiCl to the toluene gel. The thermal response of the heat-induced gel of C18AA was highly sensitive.

  19. Heat shock protein 27 (HSPB1) suppresses the PDGF-BB-induced migration of osteoblasts

    Science.gov (United States)

    Kainuma, Shingo; Tokuda, Haruhiko; Yamamoto, Naohiro; Kuroyanagi, Gen; Fujita, Kazuhiko; Kawabata, Tetsu; Sakai, Go; Matsushima-Nishiwaki, Rie; Kozawa, Osamu; Otsuka, Takanobu

    2017-01-01

    Heat shock protein 27 (HSP27/HSPB1), one of the small heat shock proteins, is constitutively expressed in various tissues. HSP27 and its phosphorylation state participate in the regulation of multiple physiological and pathophysiological cell functions. However, the exact roles of HSP27 in osteoblasts remain unclear. In the present study, we investigated the role of HSP27 in the platelet-derived growth factor-BB (PDGF-BB)-stimulated migration of osteoblast-like MC3T3-E1 cells. PDGF-BB by itself barely upregulated the expression of HSP27 protein, but stimulated the phosphorylation of HSP27 in these cells. The PDGF-BB-induced cell migration was significantly downregulated by HSP27 overexpression. The PDGF-BB-induced migrated cell numbers of the wild-type HSP27-overexpressing cells and the phospho-mimic HSP27-overexpressing (3D) cells were less than those of the unphosphorylatable HSP27-overexpressing (3A) cells. PD98059, an inhibitor of MEK1/2, SB203580, an inhibitor of p38 mitogen-activated protein kinase, and SP600125, an inhibitor of stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK) reduced the PDGF-BB-induced migration of these cells, whereas Akt inhibitor or rapamycin, an inhibitor of upstream kinase of p70 S6 kinase (mTOR), barely affected the migration. However, the PDGF-BB-induced phosphorylation of p44/p42 MAPK, p38 MAPK and SAPK/JNK was not affected by HSP27 overexpression. There were no significant differences in the phosphorylation of p44/p42 MAPK, p38 MAP kinase or SAPK/JNK between the 3D cells and the 3A cells. These results strongly suggest that HSP27 functions as a negative regulator in the PDGF-BB-stimulated migration of osteoblasts, and the suppressive effect is amplified by the phosphorylation state of HSP27. PMID:28902366

  20. Augmentation of HIFU-induced heating with fibers embedded in a phantom.

    Science.gov (United States)

    Labuda, Cecille Pemberton; Church, Charles C

    2011-03-01

    The effect of fibers on the rate of heat deposition in the focal region of high-intensity focused ultrasound (HIFU) beams was investigated. Nylon, stainless steel and copper fibers of diameters 0.23-0.25, 0.33 and 0.51-0.53 mm embedded in a phantom were exposed to HIFU. The total energy deposited was quantified by measuring the volumes of the lesions formed. The average volumes of the lesions normalized to the average volume of control lesions were 1.19±0.19, 1.43±0.19 and 2.67±0.21 for increasing nylon fiber diameter, indicating an augmented rate of heating. The maximum normalized volume of lesions at the metal fibers was 0.655. These results are consistent with the material properties, which suggest that the mechanism is increased acoustic absorption along with reduction of heat loss by the nylon fiber. The study supports the possibility of improving the efficacy of HIFU-induced hemostasis in vivo by use of a specially designed, nylon fiber-based medical appliance. Copyright © 2011 World Federation for Ultrasound in Medicine & Biology. All rights reserved.

  1. Heat generation above break-even from laser-induced fusion in ultra-dense deuterium

    Science.gov (United States)

    Holmlid, Leif

    2015-08-01

    Previous results from laser-induced processes in ultra-dense deuterium D(0) give conclusive evidence for ejection of neutral massive particles with energy >10 MeV u-1. Such particles can only be formed from nuclear processes like nuclear fusion at the low laser intensity used. Heat generation is of interest for future fusion energy applications and has now been measured by a small copper (Cu) cylinder surrounding the laser target. The temperature rise of the Cu cylinder is measured with an NTC resistor during around 5000 laser shots per measured point. No heating in the apparatus or the gas feed is normally used. The fusion process is suboptimal relative to previously published studies by a factor of around 10. The small neutral particles HN(0) of ultra-dense hydrogen (size of a few pm) escape with a substantial fraction of the energy. Heat loss to the D2 gas (at deuterium as fusion fuel. With a slightly different setup, a thermal gain of 2 is reached, thus clearly above break-even for all neutronicity values possible. Also including the large kinetic energy which is directly measured for MeV particles leaving through a small opening gives a gain of 2.3. Taking into account the lower efficiency now due to the suboptimal fusion process, previous studies indicate a gain of at least 20 during long periods.

  2. Earthquake model describes traffic jams caused by imperfect driving styles

    Science.gov (United States)

    Járai-Szabó, Ferenc; Néda, Zoltán

    2012-11-01

    The wide modeling potential of the classical spring-block type system is illustrated by an interdisciplinary application. A simple one-dimensional spring-block chain with asymmetric spring forces is used to model idealized single-lane highway traffic and the emergence of phantom traffic jams. Based on the stop-time statistics of one car in the row, a proper order parameter is defined. By extensive computer simulations the parameter space of the model is explored, analyzed and interpreted. Existence of free and congested flow phases is confirmed and the transition between them is analyzed.

  3. Jammed systems of oriented needles always percolate on square lattices

    Science.gov (United States)

    Kondrat, Grzegorz; Koza, Zbigniew; Brzeski, Piotr

    2017-08-01

    Random sequential adsorption (RSA) is a standard method of modeling adsorption of large molecules at the liquid-solid interface. Several studies have recently conjectured that in the RSA of rectangular needles, or k -mers, on a square lattice, percolation is impossible if the needles are sufficiently long (k of order of several thousand). We refute these claims and present rigorous proof that in any jammed configuration of nonoverlapping, fixed-length, horizontal, or vertical needles on a square lattice, all clusters are percolating clusters.

  4. Brain death induces renal expression of heme oxygenase-1 and heat shock protein 70

    Directory of Open Access Journals (Sweden)

    van Dullemen Leon FA

    2013-01-01

    Full Text Available Abstract Background Kidneys derived from brain dead donors have lower graft survival and higher graft-function loss compared to their living donor counterpart. Heat Shock Proteins (HSP are a large family of stress proteins involved in maintaining cell homeostasis. We studied the role of stress-inducible genes Heme Oxygenase-1 (HO-1, HSP27, HSP40, and HSP70 in the kidney following a 4 hour period of brain death. Methods Brain death was induced in rats (n=6 by inflating a balloon catheter in the epidural space. Kidneys were analysed for HSPs using RT-PCR, Western blotting, and immunohistochemistry. Results RT-PCR data showed a significant increase in gene expression for HO-1 and HSP70 in kidneys of brain dead rats. Western blotting revealed a massive increase in HO-1 protein in brain dead rat kidneys. Immunohistochemistry confirmed these findings, showing extensive HO-1 protein expression in the renal cortical tubules of brain dead rats. HSP70 protein was predominantly increased in renal distal tubules of brain dead rats treated for hypotension. Conclusion Renal stress caused by brain death induces expression of the cytoprotective genes HO-1 and HSP70, but not of HSP27 and HSP40. The upregulation of these cytoprotective genes indicate that renal damage occurs during brain death, and could be part of a protective or recuperative mechanism induced by brain death-associated stress.

  5. Heat generation above break-even from laser-induced fusion in ultra-dense deuterium

    Directory of Open Access Journals (Sweden)

    Leif Holmlid

    2015-08-01

    Full Text Available Previous results from laser-induced processes in ultra-dense deuterium D(0 give conclusive evidence for ejection of neutral massive particles with energy >10 MeV u−1. Such particles can only be formed from nuclear processes like nuclear fusion at the low laser intensity used. Heat generation is of interest for future fusion energy applications and has now been measured by a small copper (Cu cylinder surrounding the laser target. The temperature rise of the Cu cylinder is measured with an NTC resistor during around 5000 laser shots per measured point. No heating in the apparatus or the gas feed is normally used. The fusion process is suboptimal relative to previously published studies by a factor of around 10. The small neutral particles HN(0 of ultra-dense hydrogen (size of a few pm escape with a substantial fraction of the energy. Heat loss to the D2 gas (at <1 mbar pressure is measured and compensated for under various conditions. Heat release of a few W is observed, at up to 50% higher energy than the total laser input thus a gain of 1.5. This is uniquely high for the use of deuterium as fusion fuel. With a slightly different setup, a thermal gain of 2 is reached, thus clearly above break-even for all neutronicity values possible. Also including the large kinetic energy which is directly measured for MeV particles leaving through a small opening gives a gain of 2.3. Taking into account the lower efficiency now due to the suboptimal fusion process, previous studies indicate a gain of at least 20 during long periods.

  6. Transient Receptor Potential Vanilloid 1 is essential for cisplatin-induced heat hyperalgesia in mice

    Directory of Open Access Journals (Sweden)

    Carlton Susan M

    2010-03-01

    Full Text Available Abstract Background Cisplatin is primarily used for treatment of ovarian and testicular cancer. Oxaliplatin is the only effective treatment for metastatic colorectal cancer. Both are known to cause dose related, cumulative toxic effects on the peripheral nervous system and thirty to forty percent of cancer patients receiving these agents experience painful peripheral neuropathy. The mechanisms underlying painful platinum-induced neuropathy remain poorly understood. Previous studies have demonstrated important roles for TRPV1, TRPM8, and TRPA1 in inflammation and nerve injury induced pain. Results In this study, using real-time, reverse transcriptase, polymerase chain reaction (RT-PCR, we analyzed the expression of TRPV1, TRPM8, and TRPA1 induced by cisplatin or oxaliplatin in vitro and in vivo. For in vitro studies, cultured E15 rat dorsal root ganglion (DRG neurons were treated for up to 48 hours with cisplatin or oxaliplatin. For in vivo studies, trigeminal ganglia (TG were isolated from mice treated with platinum drugs for three weeks. We show that cisplatin and oxaliplatin-treated DRG neurons had significantly increased in TRPV1, TRPA1, and TRPM8 mRNA expression. TG neurons from cisplatin treated mice had significant increases in TRPV1 and TRPA1 mRNA expression while oxaliplatin strongly induced only TRPA1. Furthermore, compared to the cisplatin-treated wild-type mice, cisplatin-treated TRPV1-null mice developed mechanical allodynia but did not exhibit enhancement of noxious heat- evoked pain responses. Immunohistochemistry studies showed that cisplatin-treated mice had no change in the proportion of the TRPV1 immunopositive TG neurons. Conclusion These results indicate that TRPV1 and TRPA1 could contribute to the development of thermal hyperalgesia and mechanical allodynia following cisplatin-induced painful neuropathy but that TRPV1 has a crucial role in cisplatin-induced thermal hyperalgesia in vivo.

  7. A novel conditional gene silencing method using a tumor-specific and heat-inducible siRNA system.

    Science.gov (United States)

    Feng, Jing; Wang, Xiaoyu; Liao, Yi; Feng, Jianguo; Tang, Liling

    2016-06-01

    RNAi technology is an invaluable tool for investigating gene function. However, the non-temporal and non-spatial control is the primary limitation, which leads to siRNA leakiness and off-target effects. In this study, we inserted three kinds of HSE into tumor specific promoter hTERT, which aims to construct a temperature-inducible and tumor-specific RNAi plasmid vector. In our system, the expression of mature siRNA is tightly controlled by the heat shock-inducible and tumor-specific promoters. From the expression level of RNA and protein, we determined the efficiency of the inducible siRNA system by targeting SNCG gene in HepG2 and MCF-7 cells. Results showed that the controllable siRNA system could be induced to initiate siRNA expression by heat-induce. The silencing effect of SNCG is on a relative low level (10 %) at 37 °C, while it is significantly increased to 50 or 60 % after heat inducing at 43 °C. This new conditional siRNA system provides a novel approach to drive the siRNA expression by heat-inducible and tumor-specific promoter.

  8. Application of Photothermal Methods for Quantification of Carotenoids in Apricot Jams

    NARCIS (Netherlands)

    Dóka, O.; Bicanic, D.; Stéger-Máté, M.; Végvári, Gy

    2015-01-01

    Carotenes, found in a diversity of fruit-containing foods, are important sources of antioxidants; a good example is apricot jam. In the study described in this paper, both the total carotenoid content (TCC) as well as the content of $$\\\\upbeta $$β-carotene in six different apricot jams were

  9. Energy-Efficient Link-Layer Jamming Attacks against Wireless Sensor Network MAC Protocols

    NARCIS (Netherlands)

    Law, Y.W.; van Hoesel, L.F.W.; Doumen, J.M.; Hartel, Pieter H.; Havinga, Paul J.M.; Atluri, V.; Samarati, P.; Ning, P.; Du, W.

    2005-01-01

    A typical wireless sensor node has little protection against radio jamming. The situation becomes worse if energy efficient jamming can be achieved by exploiting knowledge of the data link layer. Encrypting the packets may help prevent the jammer from taking actions based on the content of the

  10. Jammed elastic shells-a 3D experimental soft frictionless granular system

    NARCIS (Netherlands)

    Jose, Jissy; Blab, Gerhard A.; Van Blaaderen, Alfons; Imhof, Arnout

    2015-01-01

    We present a new experimental system of monodisperse, soft, frictionless, fluorescent labeled elastic shells for the characterization of structure, universal scaling laws and force networks in 3D jammed matter. The elastic shells in a jammed packing are deformed in such a way that at each contact

  11. Differential Transform Method for Mathematical Modeling of Jamming Transition Problem in Traffic Congestion Flow

    DEFF Research Database (Denmark)

    Ganji, S.; Barari, Amin; Ibsen, Lars Bo

    2012-01-01

    In this paper we aim to find an analytical solution for jamming transition in traffic flow. Generally the Jamming Transition Problem (JTP) can be modeled via Lorentz system. So, in this way, the governing differential equation achieved is modeled in the form of a nonlinear damped oscillator...

  12. Differential Transform Method for Mathematical Modeling of Jamming Transition Problem in Traffic Congestion Flow

    DEFF Research Database (Denmark)

    Ganji, S. S.; Barari, Amin; Ibsen, Lars Bo

    2010-01-01

    In this paper we aim to find an analytical solution for jamming transition in traffic flow. Generally the Jamming Transition Problem (JTP) can be modeled via Lorentz system. So, in this way, the governing differential equation achieved is modeled in the form of a nonlinear damped oscillator...

  13. LDH inhibition impacts on heat shock response and induces senescence of hepatocellular carcinoma cells.

    Science.gov (United States)

    Manerba, Marcella; Di Ianni, Lorenza; Govoni, Marzia; Roberti, Marinella; Recanatini, Maurizio; Di Stefano, Giuseppina

    2017-07-15

    In normal cells, heat shock response (HSR) is rapidly induced in response to a variety of harmful conditions and represents one of the most efficient defense mechanism. In cancer tissues, constitutive activation converts HSR into a life-threatening process, which plays a major role in helping cell survival and proliferation. Overexpression of heat shock proteins (HSPs) has been widely reported in human cancers and was found to correlate with tumor progression. Hepatocellular carcinoma is one of the conditions in which HSR activation was shown to have the highest clinical significance. Transcription of HSPs is induced by HSF-1, which also activates glycolytic metabolism and increases the expression of LDH-A, the master regulator of the Warburg effect. In this paper, we tried to explore the relationship between HSR and LDH-A. In cultured hepatocellular carcinoma cells, by using two enzyme inhibitors (oxamate and galloflavin), we found that the reduction of LDH-A activity led to decreased level and function of the major HSPs involved in tumorigenesis. Galloflavin (a polyphenol) also inhibited the ATPase activity of two of the examined HSPs. Finally, hindering HSR markedly lowered the alpha-fetoprotein cellular levels and induced senescence. Specific inhibitors of single HSPs are currently under evaluation in different neoplastic diseases. However, one of the effects usually observed during treatment is a compensatory elevation of other HSPs, which decreases treatment efficacy. Our results highlight a connection between LDH and HSR and suggest LDH inhibition as a way to globally impact on this tumor promoting process. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Sex specific effects of heat induced hormesis in Hsf-deficient Drosophila melanogaster

    DEFF Research Database (Denmark)

    Sørensen, J G; Kristensen, Torsten Nygård; Kristensen, K V

    2007-01-01

    In insects mild heat stress early in life has been reported to increase life span and heat resistance later in life, a phenomenon termed hormesis. Here, we test if the induction of the heat shock response by mild heat stress is mediating hormesis in longevity and heat resistance at older age....... To test this hypothesis we used two heat shock transcription factor (Hsf) mutant stocks. One stock harbours a mutation giving rise to a heat sensitive Hsf which inactivates the heat shock response at high temperature and the other is a rescued mutant giving rise to a wild-type phenotype. We measured...... longevity, heat resistance and expression level of a heat shock protein, Hsp70, in controls and mildly heat treated flies. We found a marked difference between males and females with males showing a beneficial effect of the early heat treatment on longevity and heat resistance later in life in the rescued...

  15. Many-body interactions in soft jammed materials.

    Science.gov (United States)

    Höhler, Reinhard; Cohen-Addad, Sylvie

    2017-02-15

    In jammed packings of soft frictionless particles such as foams or emulsions, stress is transmitted via a network of mechanical contacts between neighbors. In generic simplified models of such materials, particle interaction energies are assumed to be pairwise additive. We report ab initio simulations of foam microstructures, showing that in general, this fundamental assumption is not justified: the conservation of bubble volumes introduces a many-body coupling between all the contacts of a given particle. It strongly modifies the relation between forces and displacements at individual contacts, in a way that cannot be captured by an effective two-body interaction. We report the impact of this effect on the linear and nonlinear elastic response of ordered bubble packings with coordination numbers ranging from 6 to 12, used as simple model systems, and we present an analytical model without free parameters which is valid as long as bubbles have an approximately spherical shape. It predicts the many-body coupling of particle contact forces, as well as the macroscopic mechanical response. For packing fractions approaching the jamming transition where contact forces go to zero, we derive an asymptotic two-body interaction law. It contains a logarithmic term, yielding a critical scaling that cannot be approximated by a power law.

  16. Motility-Driven Glass and Jamming Transitions in Biological Tissues

    Science.gov (United States)

    Bi, Dapeng; Yang, Xingbo; Marchetti, M. Cristina; Manning, M. Lisa

    2016-04-01

    Cell motion inside dense tissues governs many biological processes, including embryonic development and cancer metastasis, and recent experiments suggest that these tissues exhibit collective glassy behavior. To make quantitative predictions about glass transitions in tissues, we study a self-propelled Voronoi model that simultaneously captures polarized cell motility and multibody cell-cell interactions in a confluent tissue, where there are no gaps between cells. We demonstrate that the model exhibits a jamming transition from a solidlike state to a fluidlike state that is controlled by three parameters: the single-cell motile speed, the persistence time of single-cell tracks, and a target shape index that characterizes the competition between cell-cell adhesion and cortical tension. In contrast to traditional particulate glasses, we are able to identify an experimentally accessible structural order parameter that specifies the entire jamming surface as a function of model parameters. We demonstrate that a continuum soft glassy rheology model precisely captures this transition in the limit of small persistence times and explain how it fails in the limit of large persistence times. These results provide a framework for understanding the collective solid-to-liquid transitions that have been observed in embryonic development and cancer progression, which may be associated with epithelial-to-mesenchymal transition in these tissues.

  17. The use of civilian-type GPS receivers by the military and their vulnerability to jamming

    Directory of Open Access Journals (Sweden)

    Ludwig Combrinck

    2012-05-01

    Full Text Available We considered the impact of external influences on a GPS receiver and how these influences affect the capabilities of civilian-type GPS receivers. A standard commercial radio frequency signal generator and passive GPS antenna were used to test the sensitivity of GPS to intentional jamming; the possible effects of the terrain on the propagation of the jamming signal were also tested. It was found that the high sensitivity of GPS receivers and the low strength level of GPS satellite signals combine to make GPS receivers very vulnerable to intentional jamming or unintentional radio frequency interference. Terrain undulation was used to shield GPS antennas from the direct line-of-sight of the jamming antenna and this indicated that terrain characteristics can be used to mitigate the effects of jamming. These results illuminate the vulnerability of civilian-type GPS receivers to the possibility and the ease of disablement and establish the foundation for future work.

  18. Measuring the mechanical responses of a jammed discontinuous shear-thickening fluid

    Science.gov (United States)

    Jiang, Weifeng; Peng, Guangjian; Ma, Yi; Chen, Heng; Hu, Jiangjiang; Jia, Chao; Zhang, Taihua

    2017-11-01

    Discontinuous shear thickening observed in many dense suspensions is rather complicated but takes place as a transient. Its details after jamming are still not clear. By using a modified rheometer with an analog-to-digital converter, we show that there are three amplitude regimes of shear strain after jamming. First, the shear modulus and the force chain angle increase with strain; the jammed state gradually deepens. Second, the jammed state is stable against a further increase in shear stress; the force chain angle is constant and the force network is stable. Third, the jammed state cannot resist a further increase in shear stress; with the increase in the force chain angle, the force chain network is broken.

  19. Aloin Protects Skin Fibroblasts from Heat Stress-Induced Oxidative Stress Damage by Regulating the Oxidative Defense System

    OpenAIRE

    Fu-Wei Liu; Fu-Chao Liu; Yu-Ren Wang; Hsin-I Tsai; Huang-Ping Yu

    2015-01-01

    Oxidative stress is commonly involved in the pathogenesis of skin damage induced by environmental factors, such as heat stress. Skin fibroblasts are responsible for the connective tissue regeneration and the skin recovery from injury. Aloin, a bioactive compound in Aloe vera, has been reported to have various pharmacological activities, such as anti-inflammatory effects. The aim of this study was to investigate the protective effect of aloin against heat stress-mediated oxidative stress in hu...

  20. Heat shock protein 70, heat shock protein 32, and vascular endothelial growth factor production and their effects on lipopolysaccharide-induced apoptosis in porcine aortic endothelial cells.

    Science.gov (United States)

    Bernardini, Chiara; Zannoni, Augusta; Turba, Maria Elena; Fantinati, Paolo; Tamanini, Carlo; Bacci, Maria Laura; Forni, Monica

    2005-01-01

    Lipopolysaccharide (LPS) is a highly proactive molecule that causes in vivo a systemic inflammatory response syndrome and activates in vitro the inflammatory pathway in different cellular types, including endothelial cells (EC). Because the proinflammatory status could lead to EC injury and apoptosis, the expression of proinflammatory genes must be finely regulated through the induction of protective genes. This study aimed at determining whether an LPS exposure is effective in inducing apoptosis in primary cultures of porcine aortic endothelial cells and in stimulating heat shock protein (Hsp)70 and Hsp32 production as well as vascular endothelial growth factor (VEGF) secretion. Cells between third and eighth passage were exposed to 10 microg/mL LPS for 1, 7, 15, and 24 hours (time-course experiments) or to 1, 10, and 100 microg/mL LPS for 7 and 15 hours (dose-response experiments). Apoptosis was not affected by 1 microg/mL LPS but significantly increased in a dose-dependent manner with the highest LPS doses. Furthermore, apoptosis rate increased only till 15 hours of LPS exposure. LPS stimulated VEGF secretion in a dose-dependent manner; its effect became significant after 7 hours and reached a plateau after 15 hours. Both Hsp70 and Hsp32 expressions were induced by LPS in a dose-dependent manner after 7 hours. Subsequent studies were addressed to evaluate the protective role of Hsp32, Hsp70, and VEGF. Hemin, an Hsp32 inducer (5, 20, 50 microM), and recombinant VEGF (100 and 200 ng/mL), were added to the culture 2 hours before LPS (10 microg/mL for 24 hours); to induce Hsp70 expression, cells were heat shocked (42 degrees C for 1 hour) 15 hours before LPS (10 microg/mL for 24 hours). Hemin exposure upregulated Hsp32 expression in a dose-dependent manner and protected cells against LPS-induced apoptosis. Heat shock (HS) stimulated Hsp70 expression but failed to reduce LPS-induced apoptosis; VEGF addition did not protect cells against LPS-induced apoptosis at any

  1. Thermal stability and molecular microstructure of heat-induced cereal grains, revealed with Raman molecular microspectroscopy and differential scanning calorimetry.

    Science.gov (United States)

    Khan, Md Majibur Rahman; Yu, Peiqiang

    2013-07-03

    The objectives of the present study were to use Raman molecular microspectroscopy and differential scanning calorimetry (DSC) to reveal molecular thermal stability and thermal degradation behavior of heat-induced cereal grains and reveal the molecular chemistry of the protein structures of cereal grain tissues affected by heat processing and to quantify the protein secondary structures using multicomponent peak modeling Gaussian and Lorentzian methods. Hierarchical cluster analysis (CLA) and principal components analysis (PCA) were also conducted to identify molecular differences in the Raman spectra. Three cereal grain seeds, wheat, triticale, and corn, were used as the model for feed protein in the experiment. The specimens were autoclaved (moist heating) and dry-heated (roasted) at 121 °C for 80 min, respectively. Raman spectroscopy results revealed that there are marked differences in the secondary structures of the proteins subjected to various heating treatments of different cereals. The sensitivity of cereals to moist heating was much higher than the sensitivity to dry heating. The multivariate analyses (CLA and PCA) showed that heat treatment was significantly isolated between the different Raman raw spectra. The DSC study revealed that the thermal degradation behavior of cereals was significantly changed after moist- and dry-heat treatments. The position of the major endothermic peak of dry-heated cereals shifted toward a higher temperature, from 131.7 to 134.0 °C, suggesting the high thermal stability of dry-heated cereals. In contrast, the endothermic peak position was slightly decreased to 132.1 °C in the case of moist autoclaved heating. The digestive behavior and nutritive value of rumen-undegradable protein in animals may be related to the changes of the protein secondary molecular structure and thermal stability of the cereal grain materials, which is attributed by Raman microspectroscopy and DSC endotherm profiles.

  2. The Vibration Analysis of Tube Bundles Induced by Fluid Elastic Excitation in Shell Side of Heat Exchanger

    Science.gov (United States)

    Bao, Minle; Wang, Lu; Li, Wenyao; Gao, Tianze

    2017-09-01

    Fluid elastic excitation in shell side of heat exchanger was deduced theoretically in this paper. Model foundation was completed by using Pro / Engineer software. The finite element model was constructed and imported into the FLUENT module. The flow field simulation adopted the dynamic mesh model, RNG k-ε model and no-slip boundary conditions. Analysing different positions vibration of tube bundles by selecting three regions in shell side of heat exchanger. The results show that heat exchanger tube bundles at the inlet of the shell side are more likely to be failure due to fluid induced vibration.

  3. MHD flow and heat transfer due to the axisymmetric stretching of a sheet with induced magnetic field

    CERN Document Server

    El-Mistikawy, Tarek M A

    2016-01-01

    The full MHD equations, governing the flow due to the axisymmetric stretching of a sheet in the presence of a transverse magnetic field, can be cast in a self similar form. This allows evaluation of the induced magnetic field and its effect on the flow and heat transfer. The problem involves three parameters- the magnetic Prandtl number, the magnetic interaction number, and the Prandtl number. Numerical solutions are obtained for the velocity field, the magnetic field, and the temperature, at different values of the magnetic Prandtl number and the magnetic interaction number. The contributions of the viscous dissipation, Joule heating, and streamwise diffusion to the heat flux toward the sheet are assessed.

  4. Mapping temperature-induced conformational changes in the Escherichia coli heat shock transcription factor sigma 32 by amide hydrogen exchange

    DEFF Research Database (Denmark)

    Rist, Wolfgang; Jørgensen, Thomas J D; Roepstorff, Peter

    2003-01-01

    gene transcription. To investigate possible heat-induced conformational changes in sigma 32 we performed amide hydrogen (H/D) exchange experiments under optimal growth and heat shock conditions combined with mass spectrometry. We found a rapid exchange of around 220 of the 294 amide hydrogens at 37...... degrees C, indicating that sigma 32 adopts a highly flexible structure. At 42 degrees C we observed a slow correlated exchange of 30 additional amide hydrogens and localized it to a helix-loop-helix motif within domain sigma 2 that is responsible for the recognition of the -10 region in heat shock...

  5. Prediction and measurement of heat transfer rates for the shock-induced unsteady laminar boundary layer on a flat plate

    Science.gov (United States)

    Cook, W. J.

    1972-01-01

    The unsteady laminar boundary layer induced by the flow-initiating shock wave passing over a flat plate mounted in a shock tube was theoretically and experimentally studied in terms of heat transfer rates to the plate for shock speeds ranging from 1.695 to 7.34 km/sec. The theory presented by Cook and Chapman for the shock-induced unsteady boundary layer on a plate is reviewed with emphasis on unsteady heat transfer. A method of measuring time-dependent heat-transfer rates using thin-film heat-flux gages and an associated data reduction technique are outlined in detail. Particular consideration is given to heat-flux measurement in short-duration ionized shocktube flows. Experimental unsteady plate heat transfer rates obtained in both air and nitrogen using thin-film heat-flux gages generally agree well with theoretical predictions. The experimental results indicate that the theory continues to predict the unsteady boundary layer behavior after the shock wave leaves the trailing edge of the plate even though the theory is strictly applicable only for the time interval in which the shock remains on the plate.

  6. Heat transfer with thermal radiation on MHD particle-fluid suspension induced by metachronal wave

    Science.gov (United States)

    Bhatti, M. M.; Zeeshan, A.; Ellahi, R.

    2017-09-01

    In this article, effects of heat transfer on particle-fluid suspension induced by metachronal wave have been examined. The influence of magnetohydrodynamics (MHD) and thermal radiation are also taken into account with the help of Ohm's law and Roseland's approximation. The governing flow problem for Casson fluid model is based on continuity, momentum and thermal energy equation for fluid phase and particle phase. Taking the approximation of long wavelength and zero Reynolds number, the governing equations are simplified. Exact solutions are obtained for the coupled partial differential equations. The impact of all the embedding parameters is discussed with the help of graphs. In particular, velocity profile, pressure rise, temperature profile and trapping phenomena are discussed for all the emerging parameters. It is observed that while fluid parameter enhances the velocity profile, Hartmann number and particle volume fraction oppose the flow.

  7. Changes in chemical interactions and protein conformation during heat-induced wheat gluten gel formation.

    Science.gov (United States)

    Wang, Kai-Qiang; Luo, Shui-Zhong; Zhong, Xi-Yang; Cai, Jing; Jiang, Shao-Tong; Zheng, Zhi

    2017-01-01

    In order to elucidate the heat-induced wheat gluten gel formation mechanism, changes in chemical interactions and protein conformation were investigated during gelation. The contribution of ionic and hydrogen bonds were found to decrease from 0.746 and 4.133g/L to 0.397 and 2.733g/L, respectively, as the temperature increased from 25 to 90°C. Moreover, the free SH content remarkably decreased from 37.91 to 19.79μmol/g during gelation. Ultraviolet absorption spectra and intrinsic fluorescence spectra suggested that wheat gluten unfolded during the heating process. In addition, wheat gluten gels treated at 80 and 90°C exhibited a "steric hindrance" effect, which can be attributed to the formation of aggregates. Fourier transform infrared spectra suggested that the random coil content increased at low temperatures (40 and 50°C), whereas the content of intermolecular β-sheets due to protein aggregation increased from 38.10% to 44.28% when the gelation temperature was 90°C. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Effects of konjac glucomannan on heat-induced changes of wheat gluten structure.

    Science.gov (United States)

    Wang, Yu; Chen, Yiheng; Zhou, Yun; Nirasawa, Satoru; Tatsumi, Eizo; Li, Xiuting; Cheng, Yongqiang

    2017-08-15

    Effects of konjac glucomannan on the structure of wheat gluten were investigated at variable temperatures in this study. Dynamic oscillatory rheology study showed that konjac glucomannan conferred stiffness on gluten with a higher tan δ data at 25°C and 55°C, but this parameter was lower at 75°C and 95°C. Konjac glucomannan decreased the content of thiol equivalent groups and increased the α-helix/β-sheet content ratio, respectively. The thicker layer of gluten protein with 5% konjac glucomannan was observed by scanning electron microscopy. This study revealed that konjac glucomannan could alter the conformations of gluten proteins upon heating via non-covalent interactions and physical entanglements. It is likely that konjac glucomannan promotes protein aggregation by strengthening hydrophobic interaction at 25°C and 55°C, and alleviates heat-induced denaturation by decreasing the flexibility of polypeptide chain at higher 75°C and 95°C. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Heat treatment-induced functional and structural aspects of Mus musculus TAp63γ

    Science.gov (United States)

    Xu, Ya; Wang, Jing-Zhang; Li, Jun-Song; Huang, Xin-He; Xing, Zhi-Hua; Du, Lin-Fang

    2011-06-01

    TAp63γ plays as an important tumor suppressor gene protecting from cancer development, especially in p53-deficient cancer cells under stresses. Here, we investigated the effects of heat treatment on the functional and structural stabilities of TAp63γ by means of the electrophoretic mobility shift assay, intrinsic tryptophan fluorescence, exogenous ANS fluorescence, and CD spectroscopies. The electrophoretic mobility shift assay result showed that the DNA binding activity of GST-TAp63γ decreased above 55 °C. The intrinsic fluorescence spectra indicated an increase of the hydrophobicity and a decrease of the polarity in the microenvironments around the tyrosine and tryptophan residues. The ANS fluorescence spectra suggested that the hydrophobic pockets in TAp63γ gradually unfolded below 50 °C. The above results indicated that TAp63γ partially unfolded at 55 °C, while the CD result showed that TAp63γ still processed a pronounced secondary structure at the same temperature, suggesting that heat treatment possibly induced the molten globule state of TAp63γ, which was an intermediate state between the native and denatured protein. Taken together, TAp63γ is a relatively unstable protein, but it has higher activity than p53 at about 50 °C. The presented work also implies that TAp63γ may play an important role in stressed microenvironments especially when p53 is deficient.

  10. Modeling of fuel vapor jet eruption induced by local droplet heating

    KAUST Repository

    Sim, Jaeheon

    2014-01-10

    The evaporation of a droplet by non-uniform heating is numerically investigated in order to understand the mechanism of the fuel-vapor jet eruption observed in the flame spread of a droplet array under microgravity condition. The phenomenon was believed to be mainly responsible for the enhanced flame spread rate through a droplet cloud at microgravity conditions. A modified Eulerian-Lagrangian method with a local phase change model is utilized to describe the interfacial dynamics between liquid droplet and surrounding air. It is found that the localized heating creates a temperature gradient along the droplet surface, induces the corresponding surface tension gradient, and thus develops an inner flow circulation commonly referred to as the Marangoni convection. Furthermore, the effect also produces a strong shear flow around the droplet surface, thereby pushing the fuel vapor toward the wake region of the droplet to form a vapor jet eruption. A parametric study clearly demonstrated that at realistic droplet combustion conditions the Marangoni effect is indeed responsible for the observed phenomena, in contrast to the results based on constant surface tension approximation

  11. Characterization of a heat-shock-inducible hsp70 gene of the green alga Volvox carteri.

    Science.gov (United States)

    Cheng, Qian; Hallmann, Armin; Edwards, Lisseth; Miller, Stephen M

    2006-04-12

    The green alga Volvox carteri possesses several thousand cells, but just two cell types: large reproductive cells called gonidia, and small, biflagellate somatic cells. Gonidia are derived from large precursor cells that are created during embryogenesis by asymmetric cell divisions. The J domain protein GlsA (Gonidialess A) is required for these asymmetric divisions and is believed to function with an Hsp70 partner. As a first step toward identifying this partner, we cloned and characterized V. carteri hsp70A, which is orthologous to HSP70A of the related alga Chlamydomonas reinhardtii. Like HSP70A, V. carteri hsp70A contains multiple heat shock elements (HSEs) and is highly inducible by heat shock. Consistent with these properties, Volvox transformants that harbor a glsA antisense transgene that is driven by an hsp70A promoter fragment express Gls phenotypes that are temperature-dependent. hsp70A appears to be the only gene in the genome that encodes a cytoplasmic Hsp70, so we conclude that Hsp70A is clearly the best candidate to be the chaperone that participates with GlsA in asymmetric cell division.

  12. EXERCISE TRAINING-INDUCED CHANGES IN INFLAMMATORY MEDIATORS AND HEAT SHOCK PROTEINS IN YOUNG TENNIS PLAYERS

    Directory of Open Access Journals (Sweden)

    Ewa Ziemann

    2013-06-01

    Full Text Available Heat shock proteins (Hsp represent proteins' groups, whose protective function, may be induced by heat, reactive oxygen species, cytokines etc. We evaluated blood levels of Hsp27 and Hsp70, and their relation to skeletal muscle damage and inflammation in young tennis players before and after the conditioning camp. Blood samples were collected directly after tournament season, 3-day rest and 14-day conditioning camp that followed. Hydrogen peroxide (H2O2 demonstrated the highest concentration directly after tournament season, which significantly decreased at camp's end. The pro-inflammatory cytokines IL-1β and TNFα decreased, whereas anti-inflammatory cytokines IL-6 and IL-10 increased after 3d rest and 14d camp. Hsp27 increased after 3d rest and remained so after 14d camp, while Hsp70 decreased from baseline to camp's completion. Hsp27 and Hsp70 correlated significantly with H2O2, IL-1β and TNFα. Muscle damage, observed as creatine kinase (CK activity changes, increased after 14d camp similarly to Hsp27 and anti-inflammatory cytokines IL-6 and IL-10. Obtained data allows to conclude that decrease of Hsp27 and increase in pro-inflammatory cytokines could be a good indicator of overreaching. Reverse tendencies in these proteins may verify accuracy of conditioning camp. Finally, this training program caused an increase in the anti-inflammatory cytokines concentrations, improving individual status of recovery

  13. Heat stress-induced effects of photosystem I: an overview of structural and functional responses.

    Science.gov (United States)

    Ivanov, Alexander G; Velitchkova, Maya Y; Allakhverdiev, Suleyman I; Huner, Norman P A

    2017-09-01

    Temperature is one of the main factors controlling the formation, development, and functional performance of the photosynthetic apparatus in all photoautotrophs (green plants, algae, and cyanobacteria) on Earth. The projected climate change scenarios predict increases in air temperature across Earth's biomes ranging from moderate (3-4 °C) to extreme (6-8 °C) by the year 2100 (IPCC in Climate change 2007: The physical science basis: summery for policymakers, IPCC WG1 Fourth Assessment Report 2007; Climate change 2014: Mitigation of Climate Change, IPCC WG3 Fifth Assessment Report 2014). In some areas, especially of the Northern hemisphere, even more extreme warm seasonal temperatures may occur, which possibly will cause significant negative effects on the development, growth, and yield of important agricultural crops. It is well documented that high temperatures can cause direct damages of the photosynthetic apparatus and photosystem II (PSII) is generally considered to be the primary target of heat-induced inactivation of photosynthesis. However, since photosystem I (PSI) is considered to determine the global amount of enthalpy in living systems (Nelson in Biochim Biophys Acta 1807:856-863, 2011; Photosynth Res 116:145-151, 2013), the effects of elevated temperatures on PSI might be of vital importance for regulating the photosynthetic response of all photoautotrophs in the changing environment. In this review, we summarize the experimental data that demonstrate the critical impact of heat-induced alterations on the structure, composition, and functional performance of PSI and their significant implications on photosynthesis under future climate change scenarios.

  14. Chalcones from Angelica keiskei: Evaluation of Their Heat Shock Protein Inducing Activities.

    Science.gov (United States)

    Kil, Yun-Seo; Choi, Seul-Ki; Lee, Yun-Sil; Jafari, Mahtab; Seo, Eun-Kyoung

    2015-10-23

    Five new chalcones, 4,2',4'-trihydroxy-3'-[(2E,5E)-7-methoxy-3,7-dimethyl-2,5-octadienyl]chalcone (1), (±)-4,2',4'-trihydroxy-3'-[(2E)-6-hydroxy-7-methoxy-3,7-dimethyl-2-octenyl]chalcone (2), 4,2',4'-trihydroxy-3'-[(2E)-3-methyl-5-(1,3-dioxolan-2-yl)-2-pentenyl]chalcone (3), 2',3'-furano-4-hydroxy-4'-methoxychalcone (4), and (±)-4-hydroxy-2',3'-(2,3-dihydro-2-methoxyfurano)-4'-methoxychalcone (5), were isolated from the aerial parts of Angelica keiskei Koidzumi together with eight known chalcones, 6-13, which were identified as (±)-4,2',4'-trihydroxy-3'-[(6E)-2-hydroxy-7-methyl-3-methylene-6-octenyl]chalcone (6), xanthoangelol (7), xanthoangelol F (8), xanthoangelol G (9), 4-hydroxyderricin (10), xanthoangelol D (11), xanthoangelol E (12), and xanthoangelol H (13), respectively. Chalcones 1-13 were evaluated for their promoter activity on heat shock protein 25 (hsp25, murine form of human hsp27). Compounds 1 and 6 activated the hsp25 promoter by 21.9- and 29.2-fold of untreated control at 10 μM, respectively. Further protein expression patterns of heat shock factor 1 (HSF1), HSP70, and HSP27 by 1 and 6 were examined. Compound 6 increased the expression of HSF1, HSP70, and HSP27 by 4.3-, 1.5-, and 4.6-fold of untreated control, respectively, without any significant cellular cytotoxicities, whereas 1 did not induce any expression of these proteins. As a result, 6 seems to be a prospective HSP inducer.

  15. Heat-Labile Enterotoxin-Induced PERK-CHOP Pathway Activation Causes Intestinal Epithelial Cell Apoptosis

    Directory of Open Access Journals (Sweden)

    Xi Lu

    2017-06-01

    Full Text Available Enterotoxigenic Escherichia coli (ETEC is a leading cause of diarrhea among children and travelers in developing countries, and heat-labile enterotoxin (LT is one of the most important virulence factors. The pathogenesis of and virulence factors associated with ETEC have been well-characterized; however, the extent to which ETEC damages host cells remains unclear. In this study, we found that LT could induce decreases in intestinal epithelial cell viability and induce apoptosis in a dose- and time- dependent manner in both HCT-8 and Caco-2 cells. We analyzed the expression profiles of apoptosis-related proteins via protein array technology and found that Bax, p-p53(S46, cleaved caspase-3, and TNFRI/TNFRSF1A expression levels were significantly up-regulated in wild-type ETEC- but not in ΔLT ETEC-infected HCT-8 cells. Bax is essential for endoplasmic reticulum (ER stress-triggered apoptosis, and our RNAi experiments showed that the PERK-eIF2-CHOP pathway and reactive oxygen species (ROS are also main participants in this process. LT-induced ROS generation was decreased in CHOP-knockdown HCT-8 cells compared to that in control cells. Moreover, pretreatment with the ROS inhibitor NAC down-regulated GRP78, CHOP, Bim, and cleaved caspase-3 expression, resulting in a reduction in the apoptosis rate from 36.2 to 20.3% in LT-treated HCT-8 cells. Furthermore, ROS inhibition also attenuated LT-induced apoptosis in the small intestinal mucosa in the ETEC-inoculation mouse model.

  16. Uncertainties in the estimation of specific absorption rate during radiofrequency alternating magnetic field induced non-adiabatic heating of ferrofluids

    Science.gov (United States)

    Lahiri, B. B.; Ranoo, Surojit; Philip, John

    2017-11-01

    Magnetic fluid hyperthermia (MFH) is becoming a viable cancer treatment methodology where the alternating magnetic field induced heating of magnetic fluid is utilized for ablating the cancerous cells or making them more susceptible to the conventional treatments. The heating efficiency in MFH is quantified in terms of specific absorption rate (SAR), which is defined as the heating power generated per unit mass. In majority of the experimental studies, SAR is evaluated from the temperature rise curves, obtained under non-adiabatic experimental conditions, which is prone to various thermodynamic uncertainties. A proper understanding of the experimental uncertainties and its remedies is a prerequisite for obtaining accurate and reproducible SAR. Here, we study the thermodynamic uncertainties associated with peripheral heating, delayed heating, heat loss from the sample and spatial variation in the temperature profile within the sample. Using first order approximations, an adiabatic reconstruction protocol for the measured temperature rise curves is developed for SAR estimation, which is found to be in good agreement with those obtained from the computationally intense slope corrected method. Our experimental findings clearly show that the peripheral and delayed heating are due to radiation heat transfer from the heating coils and slower response time of the sensor, respectively. Our results suggest that the peripheral heating is linearly proportional to the sample area to volume ratio and coil temperature. It is also observed that peripheral heating decreases in presence of a non-magnetic insulating shielding. The delayed heating is found to contribute up to ~25% uncertainties in SAR values. As the SAR values are very sensitive to the initial slope determination method, explicit mention of the range of linear regression analysis is appropriate to reproduce the results. The effect of sample volume to area ratio on linear heat loss rate is systematically studied and the

  17. Heat-stress and light-stress induce different cellular pathologies in the symbiotic dinoflagellate during coral bleaching.

    Science.gov (United States)

    Downs, C A; McDougall, Kathleen E; Woodley, Cheryl M; Fauth, John E; Richmond, Robert H; Kushmaro, Ariel; Gibb, Stuart W; Loya, Yossi; Ostrander, Gary K; Kramarsky-Winter, Esti

    2013-01-01

    Coral bleaching is a significant contributor to the worldwide degradation of coral reefs and is indicative of the termination of symbiosis between the coral host and its symbiotic algae (dinoflagellate; Symbiodinium sp. complex), usually by expulsion or xenophagy (symbiophagy) of its dinoflagellates. Herein, we provide evidence that during the earliest stages of environmentally induced bleaching, heat stress and light stress generate distinctly different pathomorphological changes in the chloroplasts, while a combined heat- and light-stress exposure induces both pathomorphologies; suggesting that these stressors act on the dinoflagellate by different mechanisms. Within the first 48 hours of a heat stress (32°C) under low-light conditions, heat stress induced decomposition of thylakoid structures before observation of extensive oxidative damage; thus it is the disorganization of the thylakoids that creates the conditions allowing photo-oxidative-stress. Conversely, during the first 48 hours of a light stress (2007 µmoles m(-2) s(-1) PAR) at 25°C, condensation or fusion of multiple thylakoid lamellae occurred coincidently with levels of oxidative damage products, implying that photo-oxidative stress causes the structural membrane damage within the chloroplasts. Exposure to combined heat- and light-stresses induced both pathomorphologies, confirming that these stressors acted on the dinoflagellate via different mechanisms. Within 72 hours of exposure to heat and/or light stresses, homeostatic processes (e.g., heat-shock protein and anti-oxidant enzyme response) were evident in the remaining intact dinoflagellates, regardless of the initiating stressor. Understanding the sequence of events during bleaching when triggered by different environmental stressors is important for predicting both severity and consequences of coral bleaching.

  18. Heat-stress and light-stress induce different cellular pathologies in the symbiotic dinoflagellate during coral bleaching.

    Directory of Open Access Journals (Sweden)

    C A Downs

    Full Text Available Coral bleaching is a significant contributor to the worldwide degradation of coral reefs and is indicative of the termination of symbiosis between the coral host and its symbiotic algae (dinoflagellate; Symbiodinium sp. complex, usually by expulsion or xenophagy (symbiophagy of its dinoflagellates. Herein, we provide evidence that during the earliest stages of environmentally induced bleaching, heat stress and light stress generate distinctly different pathomorphological changes in the chloroplasts, while a combined heat- and light-stress exposure induces both pathomorphologies; suggesting that these stressors act on the dinoflagellate by different mechanisms. Within the first 48 hours of a heat stress (32°C under low-light conditions, heat stress induced decomposition of thylakoid structures before observation of extensive oxidative damage; thus it is the disorganization of the thylakoids that creates the conditions allowing photo-oxidative-stress. Conversely, during the first 48 hours of a light stress (2007 µmoles m(-2 s(-1 PAR at 25°C, condensation or fusion of multiple thylakoid lamellae occurred coincidently with levels of oxidative damage products, implying that photo-oxidative stress causes the structural membrane damage within the chloroplasts. Exposure to combined heat- and light-stresses induced both pathomorphologies, confirming that these stressors acted on the dinoflagellate via different mechanisms. Within 72 hours of exposure to heat and/or light stresses, homeostatic processes (e.g., heat-shock protein and anti-oxidant enzyme response were evident in the remaining intact dinoflagellates, regardless of the initiating stressor. Understanding the sequence of events during bleaching when triggered by different environmental stressors is important for predicting both severity and consequences of coral bleaching.

  19. Heat-Stress and Light-Stress Induce Different Cellular Pathologies in the Symbiotic Dinoflagellate during Coral Bleaching

    Science.gov (United States)

    Downs, C. A.; McDougall, Kathleen E.; Woodley, Cheryl M.; Fauth, John E.; Richmond, Robert H.; Kushmaro, Ariel; Gibb, Stuart W.; Loya, Yossi; Ostrander, Gary K.; Kramarsky-Winter, Esti

    2013-01-01

    Coral bleaching is a significant contributor to the worldwide degradation of coral reefs and is indicative of the termination of symbiosis between the coral host and its symbiotic algae (dinoflagellate; Symbiodinium sp. complex), usually by expulsion or xenophagy (symbiophagy) of its dinoflagellates. Herein, we provide evidence that during the earliest stages of environmentally induced bleaching, heat stress and light stress generate distinctly different pathomorphological changes in the chloroplasts, while a combined heat- and light-stress exposure induces both pathomorphologies; suggesting that these stressors act on the dinoflagellate by different mechanisms. Within the first 48 hours of a heat stress (32°C) under low-light conditions, heat stress induced decomposition of thylakoid structures before observation of extensive oxidative damage; thus it is the disorganization of the thylakoids that creates the conditions allowing photo-oxidative-stress. Conversely, during the first 48 hours of a light stress (2007 µmoles m−2 s−1 PAR) at 25°C, condensation or fusion of multiple thylakoid lamellae occurred coincidently with levels of oxidative damage products, implying that photo-oxidative stress causes the structural membrane damage within the chloroplasts. Exposure to combined heat- and light-stresses induced both pathomorphologies, confirming that these stressors acted on the dinoflagellate via different mechanisms. Within 72 hours of exposure to heat and/or light stresses, homeostatic processes (e.g., heat-shock protein and anti-oxidant enzyme response) were evident in the remaining intact dinoflagellates, regardless of the initiating stressor. Understanding the sequence of events during bleaching when triggered by different environmental stressors is important for predicting both severity and consequences of coral bleaching. PMID:24324575

  20. LPS-induced delayed preconditioning is mediated by Hsp90 and involves the heat shock response in mouse kidney.

    Directory of Open Access Journals (Sweden)

    Tamás Kaucsár

    Full Text Available We and others demonstrated previously that preconditioning with endotoxin (LPS protected from a subsequent lethal LPS challenge or from renal ischemia-reperfusion injury (IRI. LPS is effective in evoking the heat shock response, an ancient and essential cellular defense mechanism, which plays a role in resistance to, and recovery from diseases. Here, by using the pharmacological Hsp90 inhibitor novobiocin (NB, we investigated the role of Hsp90 and the heat shock response in LPS-induced delayed renal preconditioning.Male C57BL/6 mice were treated with preconditioning (P: 2 mg/kg, i.p. and subsequent lethal (L: 10 mg/kg, i.p. doses of LPS alone or in combination with NB (100 mg/kg, i.p.. Controls received saline (C or NB.Preconditioning LPS conferred protection from a subsequent lethal LPS treatment. Importantly, the protective effect of LPS preconditioning was completely abolished by a concomitant treatment with NB. LPS induced a marked heat shock protein increase as demonstrated by Western blots of Hsp70 and Hsp90. NB alone also stimulated Hsp70 and Hsp90 mRNA but not protein expression. However, Hsp70 and Hsp90 protein induction in LPS-treated mice was abolished by a concomitant NB treatment, demonstrating a NB-induced impairment of the heat shock response to LPS preconditioning.LPS-induced heat shock protein induction and tolerance to a subsequent lethal LPS treatment was prevented by the Hsp90 inhibitor, novobiocin. Our findings demonstrate a critical role of Hsp90 in LPS signaling, and a potential involvement of the heat shock response in LPS-induced preconditioning.

  1. Traffic jams II: an update of diseases of intracellular transport.

    Science.gov (United States)

    Aridor, Meir; Hannan, Lisa A

    2002-11-01

    As more details emerge on the mechanisms that mediate and control intracellular transport, the molecular basis for variety of human diseases has been revealed. In turn, disease pathology and physiology shed light on the intricate controls that regulate intracellular transport to assure proper cellular and tissue function and homeostasis. We previously listed a number of diseases that are the result of defects in intracellular transport, or cause defects in intracellular transport. (Aridor M, Hannan LA. Traffic Jam: A compendium of human diseases that affect intracellular transport processes. Traffic 2000; 1: 836-851). This Toolbox updates the previous list to include additional disorders that were recently identified to be related to intracellular trafficking. In the time since we have published our first list there have been significant advances in understanding of the molecular basis of these defects. Such advances will pave the way to future effective therapeutics.

  2. Resilience of LTE networks against smart jamming attacks: Wideband model

    KAUST Repository

    Aziz, Farhan M.

    2015-12-03

    LTE/LTE-A networks have been successfully providing advanced broadband services to millions of users worldwide. Lately, it has been suggested to use LTE networks for mission-critical applications like public safety, smart grid and military communications. We have previously shown that LTE networks are vulnerable to Denial-of-Service (DOS) and loss of service attacks from smart jammers. In this paper, we extend our previous work on resilience of LTE networks to wideband multipath fading channel, SINR estimation in frequency domain and computation of utilities based on observable parameters under the framework of single-shot and repeated games with asymmetric information. In a single-shot game formulation, network utility is severely compromised at its solutions, i.e. at the Nash Equilibria (NE). We propose evolved repeated-game strategy algorithms to combat smart jamming attacks that can be implemented in existing deployments using current technology. © 2015 IEEE.

  3. Identification and characterisation of human Junctional Adhesion Molecule (JAM).

    Science.gov (United States)

    Williams, L A; Martin-Padura, I; Dejana, E; Hogg, N; Simmons, D L

    1999-12-01

    It is widely believed that migrating immune cells utilise the intercellular junctions as routes of passage, and in doing so cause the transient disruption of junctional structures. Thus there is much interest in the molecules that have been identified at cell-cell contact points and their potential involvement in the control of leukocyte diapedesis. In this report we describe the human orthologue to Junctional Adhesion Molecule (JAM), a recently identified member of the immunoglobulin superfamily expressed at intercellular junctions (Martin-Padura et al., 1998). The human protein shares a highly conserved structure and sequence with the murine protein. However it is distinct in that it is constitutively expressed on circulating neutrophils, monocytes, platelets and lymphocyte subsets. This broad expression pattern is similar to another IgSF molecule, CD31, expressed at intercellular junctions, and may indicate further complexities in the control of leukocyte/ endothelial interactions.

  4. Synthetic Radar Echoes in the Presence of Jamming

    Science.gov (United States)

    1945-06-22

    t~r..e ’ýexjerimente.1) o 12 tMc/sec .5.8 IjASOC un we: 0,37 1 9 1 16 C 6 I2 02 0 Z4 17 0 0-0!>41 C 10 (video bandwidth limi~ting The I f’ narrowva4...Aa stated. this is about 2 db smaller thmn the signsl that can be se’n 100% of the time However, suzh a signal is stijl an eyceedingly amall Increase...1, 0.3, 0.1 tsee were chosen; the i-f b1-ndwitth w- verled from 12’, l:c/’se- to 17 Mc/sec in four steps; the intensity of the jamming (.arrier

  5. Jammed Humans in High-Density Crowd Disasters

    Science.gov (United States)

    Bottinelli, Arianna; Sumpter, David; Silverberg, Jesse

    When people gather in large groups like those found at Black Friday sales events, pilgrimages, heavy metal concerts, and parades, crowd density often becomes exceptionally high. As a consequence, these events can produce tragic outcomes such as stampedes and ''crowd crushes''. While human collective motion has been studied with active particle simulations, the underlying mechanisms for emergent behavior are less well understood. Here, we use techniques developed to study jammed granular materials to analyze an active matter model inspired by large groups of people gathering at a point of common interest. In the model, a single behavioral rule combined with body-contact interactions are sufficient for the emergence of a self-confined steady state, where particles fluctuate around a stable position. Applying mode analysis to this system, we find evidence for Goldstone modes, soft spots, and stochastic resonance, which may be the preferential mechanisms for dangerous emergent collective motions in crowds.

  6. Pulp colour evaluation of dried sweet tomatoes to prepare jams.

    Directory of Open Access Journals (Sweden)

    Delia Paola Urfalino-Rodríguez

    2015-12-01

    Full Text Available The objective of this study was to evaluate the colour of dried sweet tomatoes, to prepare jams. The assay was carried out during 2013 at the Fruits and Vegetables Drying Laboratory from the National Institute of Agricultural Technology (INTA Rama Caída Agricultural Experimental Station, Argentina. Franco variety tomatoes were used; these were peeled and cut, then 8 groups of 0,5 kg each were formed in order to attain 4 treatments with two repetitions. The tomatoes were covered with sucrose (0,5 kg mixed with four doses of sodium metabisulfite (A: 0%; B: 0,2%; C: 0,5%; D: 0,8% and were left resting 24 hours. They were rinsed and dehydrated in an electric oven with forced ventilation at 55 °C until 0,47 ± 0,02 (humidity inferior to 20 % of water activity was reached. Subsequently, the colour of the pulp of the dried tomatoes was measured every three months and the content of sulphur dioxide was determined after one year in storage. The four treatments evaluated presented stable colours in time; however, treatments C and D showed the highest values in colour space CIE L*, a*, b* (most intense and attractive red colours. Also, these treatments were the ones with the greatest residual amount of sulphur dioxide, however, they were below of the allowed limit established by the Argentine Food Code for the manufacturing of jams(C 160 ± 22,63; D 1.160 ± 214,96 ppm.

  7. EMF protects cardiomyocytes against hypoxia-induced injury via heat shock protein 70 activation.

    Science.gov (United States)

    Wei, Jinhong; Tong, Jie; Yu, Liying; Zhang, Jianbao

    2016-03-25

    Intracellular calcium (Ca(2+)i) overload induced by chronic hypoxia alters Ca(2+)i homeostasis, whereas ameliorating calcium homeostasis is believed to be responsible for cardioprotection. We hypothesize that cardioprotection by electromagnetic fields (EMF) exposure may restore Ca(2+)i homeostasis altered by hypoxia insults. Cardiomyocytes isolated from neonatal Sprague-Dawley rats were exposed to chronic hypoxia (1% O2, 5% CO2, 37 °C). We observed that cardiomyocytes injury and hypertrophy were alleviated in hypoxic cardiomyocytes exposed with EMF preconditioning. Compared with hypoxic cardiomyocytes, the diastolic [Ca(2+)]i was decreased, the amplitude of Ca(2+)i oscillations was recovered when cardiomyocytes exposed with EMF. In addition, we also found that EMF exposure significantly increased heat shock protein 70 (HSP70) mRNA expression in hypoxic cardiomyocytes. However, treatment with HSP70 blocker KNK437, almost completely inhibited the EMF induced-cardioprotection and the beneficial effects of Ca(2+) oscillation in hypoxic cardiomyocytes. These results suggest that EMF preconditioning ameliorates Ca(2+)i homeostasis through activating HSP70, thereby producing the cardioprotective effect and reduction in hypoxic cardiomyocytes damage. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  8. The role of intra-domain disulfide bonds in heat-induced irreversible denaturation of camelid single domain VHH antibodies.

    Science.gov (United States)

    Akazawa-Ogawa, Yoko; Uegaki, Koichi; Hagihara, Yoshihisa

    2016-01-01

    Camelid-derived single domain VHH antibodies are highly heat resistant, and the mechanism of heat-induced VHH denaturation predominantly relies on the chemical modification of amino acids. Although chemical modification of disulfide bonds has been recognized as a cause for heat-induced denaturation of many proteins, there have been no mutagenesis studies, in which the number of disulfide bonds was controlled. In this article, we examined a series of mutants of two different VHHs with single, double or no disulfide bonds, and scrutinized the effects of these disulfide bond modifications on VHH denaturation. With the exception of one mutant, the heat resistance of VHHs decreased when the number of disulfide bonds increased. The effect of disulfide bonds on heat denaturation was more striking if the VHH had a second disulfide bond, suggesting that the contribution of disulfide shuffling is significant in proteins with multiple disulfide bonds. Furthermore, our results directly indicate that removal of a disulfide bond can indeed increase the heat resistance of a protein, irrespective of the negative impact on equilibrium thermodynamic stability. © The Authors 2015. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.

  9. Preliminary Studies Regarding the Production of Jam from Organic Rose Petal

    Directory of Open Access Journals (Sweden)

    Ana Cornelia BUTCARU

    2017-11-01

    The final products, seventeen variants of rose jam, were analyzed and tasted. Sensorial analysis was made by consumers of different ages and gender. Jam appearance, general taste, aroma, and the overall impression were noticed. V4 variant - Brother Cadfael with sea buckthorn was the most appreciated variant. For each of these top variants, target group by gender and age was analyzed. The results showed that the customers’ preferences are influenced by age and gender and the organic rose jam is a highly appreciated product.

  10. Heat-induced inactivation mechanisms of Kunitz trypsin inhibitor and Bowman-Birk inhibitor in soymilk processing.

    Science.gov (United States)

    Chen, Yeming; Xu, Zhicun; Zhang, Caimeng; Kong, Xiangzhen; Hua, Yufei

    2014-07-01

    Trypsin inhibitor activity (TIA) is an important antinutritional factor in soymilk. In this study, the effects of NaCl preaddition on TIA and the heat-induced TIA inactivation mechanisms were examined. The results showed that Kunitz trypsin inhibitor (KTI) and Bowman-Birk inhibitor (BBI) contributed 74% and 26% to raw soymilk TIA, respectively. The heat-induced quick KTI incorporation into protein aggregates was the reason for its quick TIA inactivation. The heat-induced slow cleavage of one BBI peptide bond was the reason for its slow TIA inactivation. Heat-induced protein aggregate formation had little effect on BBI inactivation owing to the fact that BBI and its degradation product tended to remain in the supernatant (197,000g, 1h) in all conditions used in this study. NaCl could accelerate the KTI incorporation into protein aggregates and the cleavage of one BBI peptide bond, which supplied a simple and quick method for low TIA soymilk processing. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Application of X-ray phase-contrast tomography in quantative studies of heat induced structural changes in meat

    DEFF Research Database (Denmark)

    Miklos, R.; Nielsen, M. S.; Einarsdottir, Hildur

    2013-01-01

    X-ray computed tomography is increasingly used in the studies of food structure. This paper describes the perspectives of use of phase contrast computed tomography in studies of heat induced structural changes in meat. From the data it was possible to obtain reconstructed images of the sample...

  12. IMP improves water-holding capacity, physical and sensory properties of heat-induced gels from porcine meat.

    Science.gov (United States)

    Nakamura, Yukinobu; Migita, Koshiro; Okitani, Akihiro; Matsuishi, Masanori

    2014-05-01

    Water-holding capacity (WHC) of heat-induced pork gels was examined. The heat-induced gels were obtained from meat homogenates prepared by adding nine volumes of 0.3-0.5 mol/L NaCl solutions containing 9-36 mmol/L disodium inosine-5'-monophosphate (IMP) or 9 mmol/L tetrapotassium pyrophosphate (KPP) to minced pork. IMP at 36 mmol/L enhanced the WHC to the same level as attained by KPP. Physical and sensory properties of heat-induced gels were also examined. The heat-induced gels were prepared from porcine meat homogenates containing 0.3 mol/L NaCl and 9-36 mmol/L IMP or 9 mmol/L KPP. IMP at 36 mmol/L enhanced the values of hardness, cohesiveness, gumminess and springiness, measured with a Tensipresser, and several organoleptic scores to the same level as the score attained by KPP. Thus, it is concluded that IMP is expected to be a practical substitute for pyrophosphates to improve the quality of sausages. © 2014 Japanese Society of Animal Science.

  13. Heat-induced denaturation and aggregation of ovalbumin at neutral pH described by irreversible first-order kinetics

    NARCIS (Netherlands)

    Weijers, M.; Barneveld, P.A.; Cohen Stuart, M.A.; Visschers, R.W.

    2003-01-01

    The heat-induced denaturation kinetics of two different sources of ovalbumin at pH 7 was studied by chromatography and differential scanning calorimetry. The kinetics was found to be independent of protein concentration and salt concentration, but was strongly dependent on temperature. For highly

  14. TARGETED DELETION OF INDUCIBLE HEAT SHOCK PROTEIN 70 ABROGATES THE LATE INFARCT-SPARING EFFECT OF MYOCARDIAL ISCHEMIC PRECONDITIONING

    Science.gov (United States)

    Abstract submitted for 82nd annual meeting of the American Association for Thoracic Surgery, May 4-8, 2002 in Washington D.C.Targeted Deletion of Inducible Heat Shock Protein 70 Abrogates the Late Infarct-Sparing Effect of Myocardial Ischemic PreconditioningCraig...

  15. Small-angle X-ray scattering studies of metastable intermediates of beta-lactoglobulin isolated after heat-induced aggregation

    DEFF Research Database (Denmark)

    Carrotta, R.; Arleth, L.; Pedersen, J.S.

    2003-01-01

    Small-angle x-ray scattering was used for studying intermediate species, isolated after heat-induced aggregation of the A variant of bovine P-lactoglobulin. The intermediates were separated in two fractions, the heated metastable dimer and heated metastable oligomers larger than the dimer. The pa...

  16. Tolerence for work-induced heat stress in men wearing liquidcooled garments

    Science.gov (United States)

    Blockley, W. V.; Roth, H. P.

    1971-01-01

    An investigation of the heat tolerance in men unable to dispose of metabolic heat as fast as it is produced within the body is discussed. Examinations were made of (a) the effect of work rate (metabolic rate) on tolerance time when body heat storage rate is a fixed quantity, and (b) tolerance time as a function of metabolic rate when heat loss is terminated after a thermal quasi-equilibrium was attained under comfortable conditions of heat transfer. The nature of the physiological mechanisms involved in such heat stress situations, and the possibility of using prediction techniques to establish standard procedures in emergencies involving cooling system failures are also discussed.

  17. Optimization of a one-step heat-inducible in vivo mini DNA vector production system.

    Directory of Open Access Journals (Sweden)

    Nafiseh Nafissi

    Full Text Available While safer than their viral counterparts, conventional circular covalently closed (CCC plasmid DNA vectors offer a limited safety profile. They often result in the transfer of unwanted prokaryotic sequences, antibiotic resistance genes, and bacterial origins of replication that may lead to unwanted immunostimulatory responses. Furthermore, such vectors may impart the potential for chromosomal integration, thus potentiating oncogenesis. Linear covalently closed (LCC, bacterial sequence free DNA vectors have shown promising clinical improvements in vitro and in vivo. However, the generation of such minivectors has been limited by in vitro enzymatic reactions hindering their downstream application in clinical trials. We previously characterized an in vivo temperature-inducible expression system, governed by the phage λ pL promoter and regulated by the thermolabile λ CI[Ts]857 repressor to produce recombinant protelomerase enzymes in E. coli. In this expression system, induction of recombinant protelomerase was achieved by increasing culture temperature above the 37°C threshold temperature. Overexpression of protelomerase led to enzymatic reactions, acting on genetically engineered multi-target sites called "Super Sequences" that serve to convert conventional CCC plasmid DNA into LCC DNA minivectors. Temperature up-shift, however, can result in intracellular stress responses and may alter plasmid replication rates; both of which may be detrimental to LCC minivector production. We sought to optimize our one-step in vivo DNA minivector production system under various induction schedules in combination with genetic modifications influencing plasmid replication, processing rates, and cellular heat stress responses. We assessed different culture growth techniques, growth media compositions, heat induction scheduling and temperature, induction duration, post-induction temperature, and E. coli genetic background to improve the productivity and

  18. Instrumental and sensory characterization of heat-induced odorants in aseptically packaged soy milk.

    Science.gov (United States)

    Lozano, Patricio R; Drake, Maryanne; Benitez, Daniel; Cadwallader, Keith R

    2007-04-18

    Predominant heat-induced odorants generated in soy milk by ultrahigh-temperature (UHT) processing were evaluated by sensory and instrumental techniques. Soy milks processed by UHT (143 degrees C/14 s, 143 degrees C/59 s, 154 degrees C/29 s) were compared to a control soy milk (90 degrees C/10 min) after 0, 1, and 7 days of storage (4.4 +/- 1 degrees C). Dynamic headspace dilution analysis (DHDA) and solvent-assisted flavor evaporation (SAFE) in conjunction with GC-olfactometry (GCO)/aroma extract dilution techniques and GC-MS were used to identify and quantify major aroma-active compounds. Sensory results revealed that intensities of overall aroma and sulfur and sweet aromatic flavors were affected by the processing conditions. Odorants mainly responsible for the changes in sulfur perception were methional, methanethiol, and dimethyl sulfide. Increases in 2-acetyl-1-pyrroline, 2-acetyl-thiazole, and 2-acetyl-2-thiazoline intensities were associated with roasted aromas. A marginal increase in intensity of sweet aromatic flavor could be explained by increases in 2,3-butanedione, 3-hydroxy-2-butanone, beta-damascenone, and 2- and 3-methylbutanal. Predominant lipid-derived odorants, including (E,E)-2,4-nonadienal, (E,E)-2,4-decadienal, (E,Z)-2,4-decadienal, (E)-2-nonenal, (E)-2-octenal, 1-octen-3-one, 1-octen-3-ol, and (E,Z)-2,6-nonadienal, were affected by processing conditions. Intensities of overall aroma and sulfur notes in soy milk decreased during storage, whereas other sensory attributes did not change. Color changes, evaluated by using a Chroma-meter, indicated all UHT heating conditions used in this study generated a more yellow and saturated color in soy milk in comparison to the control soy milk.

  19. Exploiting absorption-induced self-heating in solar cells (Conference Presentation)

    Science.gov (United States)

    Ullbrich, Sascha; Fischer, Axel; Erdenebileg, Enkhtur; Koerner, Christian; Reineke, Sebastian; Leo, Karl; Vandewal, Koen

    2017-04-01

    Absorption of light inevitably leads to a self-heating of each type of solar cell, either due to the excess energy of absorbed photons or non-radiative recombination of charge carriers. Although the effect of temperature on solar cell parameters such as the open-circuit voltage are well known, it is often ignored in Suns-Voc measurements [1]. This measurement technique enables direct access to the diode ideality factor without an influence by series resistance. A frequently seen decrease of the ideality factor or a saturation of the open-circuit voltage at high illumination intensities is often attributed solely to surface recombination [2], the shape of the density of states (DOS) [3], or the quality of the back contact in inorganic solar cells [4]. In this work, we present an analytical model for taking into account absorption induced self-heating in Suns-Voc measurements and validate it for various solar cell technologies such as small molecule organic solar cells, perovskite solar cells, and inorganic solar cells. Furthermore, with an adapted Suns-Voc technique, we are able to not only correctly determine the ideality factor, but also the relevant energy gap of the solar cell, which is especially of interest in the field of novel solar cell technologies. [1] R.A. Sinton and A. Cuevas, EU PVSEC, 1152-1155 (2000) [2] K. Tvingstedt and C. Deibel, Adv. Energy Mater. 6, 1502230 (2016) [3] T. Kirchartz and J. Nelson, Phys. Rev. B 86, 165201 (2012) [4] S. Glunz, J. Nekarda, H. Maeckel et al., EU PVSEC, 849-853 (2007)

  20. Rapid insight into heating-induced phase transformations in the solid state of the calcium salt of atorvastatin using multivariate data analysis

    DEFF Research Database (Denmark)

    Christensen, Niels Peter Aae; Van Eerdenbrugh, Bernard; Kwok, Kaho

    2013-01-01

    To investigate the heating-induced dehydration and melting behavior of the trihydrate phase of the calcium salt of atorvastatin.......To investigate the heating-induced dehydration and melting behavior of the trihydrate phase of the calcium salt of atorvastatin....

  1. Heat and water stress induce unique transcriptional signatures of heat-shock proteins and transcription factors in grapevine.

    Science.gov (United States)

    Rocheta, Margarida; Becker, Jörg D; Coito, João L; Carvalho, Luísa; Amâncio, Sara

    2014-03-01

    Grapevine is an extremely important crop worldwide.In southern Europe, post-flowering phases of the growth cycle can occur under high temperatures, excessive light, and drought conditions at soil and/or atmospheric level. In this study, we subjected greenhouse grown grapevine, variety Aragonez, to two individual abiotic stresses, water deficit stress(WDS), and heat stress (HS). The adaptation of plants to stress is a complex response triggered by cascades of molecular net works involved in stress perception, signal transduction, and the expression of specific stress-related genes and metabolites. Approaches such as array-based transcript profiling allow assessing the expression of thousands of genes in control and stress tissues. Using microarrays, we analyzed the leaf transcriptomic profile of the grapevine plants. Photosynthesis measurements verified that the plants were significantly affected by the stresses applied. Leaf gene expression was obtained using a high-throughput transcriptomic grapevine array, the 23K custom-made Affymetrix Vitis GeneChip. We identified 1,594 genes as differentially expressed between control and treatments and grouped them into ten major functional categories using MapMan software. The transcriptome of Aragonez was more significantly affected by HS when compared with WDS. The number of genes coding for heat-shock proteins and transcription factors expressed solely in response to HS suggesting their expression as unique signatures of HS. However, across-talk between the response pathways to both stresses was observed at the level of AP2/ERF transcription factors.

  2. Role and mechanism of endoplasmic reticulum stress and Ca2+ overload in pulmonary endothelial cell damage induced by heat stress

    Directory of Open Access Journals (Sweden)

    Bao-jun YU

    2017-08-01

    Full Text Available Objective To observe the effect of different temperatures on endoplasmic reticulum stress, calcium overload, mitochondria and cell damage in pulmonary microvascular endothelial cells (PMVEC induced by heat stress, and clarify the mechanism of endothelial cell injury in the process of heat stress to provide experimental basis for clinical prevention and treatment of heat stree. Methods Heat stress model of PMVEC cell was set up. Control group cells were incubated at 37℃, 5%CO2, while heat stress group cells were incubated at 39℃, 41℃, 43℃ for 2h, respectively, then further incubated at 37℃, 5%CO2 for 6h. Pretreatment of cells with 20μmol/L BAPTA-AM or 50μmol/L CsA before heat stress at 43℃. The protein levels of p-PERK, PERK p-eIF2a, eIF2a, ATF4 and GRP78 were analyzed by Western blotting. Intracellular Ca2+, mitochondrial membrane potential and the changes in mitochondrial permeability transition pore were investigated by flow cytometry. The change of caspase-3 was detected by Caspase Assay Kit. Millicell-ERS Volt-Ohm Meter and Accessories was used for determining the changes of transepithelium electrical resistance (TER. Results Compared with the control group, with the increase of heat stress temperature (41-43℃, the phosphorylation of p-PERK and p-eIF2a protein and the expressions of ATF4 and GRP78 proteins were gradually activated, intracellular Ca2+ increased, MPTP pore was opened, mitochondrial membrane potential decreased, cell permeability increased and apoptosis occurred, and it was the most obvious in the 43℃ heat stress group, and the difference was statistically significant (P<0.05. Pretreatment with Ca2+ inhibitors promoted the recovery of the MPTP hole, mitochondrial membrane potential and cell permeability, and reduced the occurrence of apoptosis. While pretreatment with the mitochondrial protective agent did not reduce the release of Ca2+, but it could promote the recovery of cell permeability and reduce the

  3. Influence of Orientation and Radiative Heat Transfer on Aluminum Foams in Buoyancy-Induced Convection

    Directory of Open Access Journals (Sweden)

    Marijn Billiet

    2015-10-01

    Full Text Available Two differently-produced open-cell aluminum foams were compared to a commercially available finned heat sink. Further, an aluminum plate and block were tested as a reference. All heat sinks have the same base plate dimensions of four by six inches. The first foam was made by investment casting of a polyurethane preform and has a porosity of 0.946 and a pore density of 10 pores per linear inch. The second foam is manufactured by casting over a solvable core and has a porosity of 0.85 and a pore density of 2.5 pores per linear inch. The effects of orientation and radiative heat transfer are experimentally investigated. The heat sinks are tested in a vertical and horizontal orientation. The effect of radiative heat transfer is investigated by comparing a painted/anodized heat sink with an untreated one. The heat flux through the heat sink for a certain temperature difference between the environment and the heat sink’s base plate is used as the performance indicator. For temperature differences larger than 30 °C, the finned heat sink outperforms the in-house-made aluminum foam heat sink on average by 17%. Furthermore, the in-house-made aluminum foam dissipates on average 12% less heat than the other aluminum foam for a temperature difference larger than 40 °C. By painting/anodizing the heat sinks, the heat transfer rate increased on average by 10% to 50%. Finally, the thermal performance of the horizontal in-house-made aluminum foam heat sink is up to 18% larger than the one of the vertical aluminum foam heat sink.

  4. E × B shear pattern formation by radial propagation of heat flux wavesa)

    Science.gov (United States)

    Kosuga, Y.; Diamond, P. H.; Dif-Pradalier, G.; Gürcan, Ã.-. D.

    2014-05-01

    A novel theory to describe the formation of E ×B flow patterns by radially propagating heat flux waves is presented. A model for heat avalanche dynamics is extended to include a finite delay time between the instantaneous heat flux and the mean flux, based on an analogy between heat avalanche dynamics and traffic flow dynamics. The response time introduced here is an analogue of the drivers' response time in traffic dynamics. The microscopic foundation for the time delay is the time for mixing of the phase space density. The inclusion of the finite response time changes the model equation for avalanche dynamics from Burgers equation to a nonlinear telegraph equation. Based on the telegraph equation, the formation of heat flux jams is predicted. The growth rate and typical interval of jams are calculated. The connection of the jam interval to the typical step size of the E ×B staircase is discussed.

  5. DMP: detouring using multiple paths against jamming attack for ubiquitous networking system.

    Science.gov (United States)

    Kim, Mihui; Chae, Kijoon

    2010-01-01

    To successfully realize the ubiquitous network environment including home automation or industrial control systems, it is important to be able to resist a jamming attack. This has recently been considered as an extremely threatening attack because it can collapse the entire network, despite the existence of basic security protocols such as encryption and authentication. In this paper, we present a method of jamming attack tolerant routing using multiple paths based on zones. The proposed scheme divides the network into zones, and manages the candidate forward nodes of neighbor zones. After detecting an attack, detour nodes decide zones for rerouting, and detour packets destined for victim nodes through forward nodes in the decided zones. Simulation results show that our scheme increases the PDR (Packet Delivery Ratio) and decreases the delay significantly in comparison with rerouting by a general routing protocol on sensor networks, AODV (Ad hoc On Demand Distance Vector), and a conventional JAM (Jammed Area Mapping) service with one reroute.

  6. DMP: Detouring Using Multiple Paths against Jamming Attack for Ubiquitous Networking System

    Directory of Open Access Journals (Sweden)

    Mihui Kim

    2010-04-01

    Full Text Available To successfully realize the ubiquitous network environment including home automation or industrial control systems, it is important to be able to resist a jamming attack. This has recently been considered as an extremely threatening attack because it can collapse the entire network, despite the existence of basic security protocols such as encryption and authentication. In this paper, we present a method of jamming attack tolerant routing using multiple paths based on zones. The proposed scheme divides the network into zones, and manages the candidate forward nodes of neighbor zones. After detecting an attack, detour nodes decide zones for rerouting, and detour packets destined for victim nodes through forward nodes in the decided zones. Simulation results show that our scheme increases the PDR (Packet Delivery Ratio and decreases the delay significantly in comparison with rerouting by a general routing protocol on sensor networks, AODV (Ad hoc On Demand Distance Vector, and a conventional JAM (Jammed Area Mapping service with one reroute.

  7. Changes in the expression of Heat Shock Proteins in ovaries from bovines with cystic ovarian disease induced by ACTH.

    Science.gov (United States)

    Velázquez, Melisa M L; Salvetti, Natalia R; Amweg, Ayelen N; Díaz, Pablo U; Matiller, Valentina; Ortega, Hugo H

    2013-12-01

    Cystic ovarian disease (COD), which is considered one of the most important causes of reproductive failure in dairy cattle, induces intraovarian changes in the expression of numerous genes. The purpose of this study was to analyze the changes in the expression of Heat Shock Proteins (HSPs) in ovaries from bovines with cystic ovarian disease induced by ACTH. Immunoreactivity for Heat Shock Proteins (HSPs) in ovaries of cows with induced COD showed differential expression patterns in growing follicles from the control group. The immunopositive area for Hsp27 and Hsp60 in granulosa cells showed significant differences between tertiary follicles from normal cycling animals and those from animals with induced COD. The cysts showed increased Hsp27 immunostaining in theca cells in relation to tertiary follicles from normal cycling cows. Hsp70 immunostaining was more intense in cystic follicles than in other follicular categories from animals with induced COD, in both granulosa and theca cells. In granulosa cells, tertiary follicles from the control group showed higher levels of Hsp90 than cysts. These results demonstrate that there are differences in HSP protein expression when COD is induced. In fact, HSP expression would be part of the functional response to the changes in hormones and neurotransmitters induced by stress, indicating that HSPs can control hormonal functions and vice versa. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Growth of novel ceramic layers on metals via chemical and heat treatments for inducing various biological functions

    Directory of Open Access Journals (Sweden)

    Tadashi eKokubo

    2015-10-01

    Full Text Available The present authors’ systematic studies on growth of novel ceramic layers on Ti metal and its alloys by chemical and heat treatments for inducing bone-bonding bioactivity and some other biological functions are reviewed. Ti metal formed an apatite on its surface in a simulated body fluid (SBF, when heat-treated after exposure to strong acid solutions to form rutile surface layer, or to strong alkali solutions to form sodium titanate surface layer. Both types of Ti metal tightly bonded to the living bone.The alkali and heat treatment was applied to the surface Ti metal of an artificial hip joint and successfully used in the clinic since 2007. The acid and heat treatments was applied to porous Ti metal to induce osteoconductivity as well as osteoinductivity. The resulting product was successfully used in clinical trials for spinal fusion devices. For the Ti-based alloys, the alkali and heat treatment was a little modified to form calcium titanate surface layer. Bone-growth promoting Mg, Sr, and Zn ions as well as the antibacterial Ag ion were successfully incorporated into the calcium titanate layer.

  9. Effects of laser-induced heating on nitrogen-vacancy centers and single-nitrogen defects in diamond

    Science.gov (United States)

    Szczuka, Conrad; Drake, Melanie; Reimer, Jeffrey A.

    2017-10-01

    We investigate the effects of laser-induced heating of NV- and P1 defects in diamonds by X-band CW EPR spectroscopy, with particular attention to temperature effects on the zero field splitting and electron polarization. A 532 nm laser with intensities of 7-36 mW mm-2 is sufficient to heat diamond samples from room temperature to 313-372 K in our experimental setup. The temperature effects on the determined NV- zero-field splittings are consistent with previously observed non-optical heating experiments. Electron spin polarization of the NV- defects were observed to increase, then saturate, with increasing laser light intensities up to 36 mW mm-2 after accounting for heating effects. We observe that EPR signal intensities from P1 centers do not follow a Boltzmann trend with laser-induced sample heating. These findings have bearing on the design of diamond-based polarization devices and magnetometry applications.

  10. Melting and thermal ablation of a silver film induced by femtosecond laser heating: a multiscale modeling approach

    Science.gov (United States)

    Ji, Pengfei; Zhang, Yuwen

    2017-10-01

    The femtosecond laser pulse heating of silver film is investigated by performing quantum mechanics (QM), molecular dynamics (MD), and two-temperature model (TTM) integrated multiscale simulation. The laser excitation dependent electron thermophysical parameters (electron heat capacity, electron thermal conductivity, and effective electron-phonon coupling factor) are determined from ab initio QM calculation, and implemented into TTM description of electron thermal excitation, heat conduction, as well as electron-phonon coupled thermal energy transport. The kinetics of atomic motion is modeled by MD simulation. Energy evolution of excited electron subsystem is described by TTM in continuum. The MD and TTM are coupled by utilizing the effective electron-phonon coupling factor. Laser heating with varying laser fluences is systematically studied to determine the thresholds of homogeneous melting and ablation. The thermal ablation induced by rapid expansion of locally and excessively superheated silver is reported. This paper provides a basis for interpreting the phase-change process induced by laser heating, and facilitates the advancement of femtosecond laser pulse processing of material.

  11. SPRINT-INTERVAL TRAINING INDUCES HEAT SHOCK PROTEIN 72 IN RAT SKELETAL MUSCLES

    Directory of Open Access Journals (Sweden)

    Yuji Ogura

    2006-06-01

    Full Text Available Previous studies have demonstrated that endurance exercise training increases the level of heat shock proteins (HSPs in skeletal muscles. However, little attention has been drawn to the effects of high intensity-short duration exercise, or sprint- interval training (SIT on HSP72 level in rat skeletal muscles. This study performed to test the hypothesis that the SIT would induce the HSP72 in fast and slow skeletal muscles of rats. Young male Wistar rats (8 weeks old were randomly assigned to a control (CON or a SIT group (n = 8/group. Animals in the SIT group were trained (1 min/sprint, 6~10 sets/day and 5~6 days/week on a treadmill for 9 weeks. After the training period, HSP72 levels in the plantaris (fast and soleus (slow muscles were analyzed by Western blotting method. Enzyme activities (hexokinase, phosphofructokinase and citrate synthase and histochemical properties (muscle fiber type compositions and cross sectional area in both muscles were also determined. The SIT resulted in significantly (p < 0.05 higher levels of HSP72 in both the plantaris and soleus muscles compared to the CON group, with the plantaris producing a greater HSP72 increase than the soleus (plantaris; 550 ± 116%, soleus; 26 ± 8%, p < 0.05. Further, there were bioenergetic improvements, fast-to-slow shift of muscle fiber composition and hypertrophy in the type IIA fiber only in the plantaris muscle. These findings indicate that the SIT program increases HSP72 level of the rat hindlimb muscles, and the SIT-induced accumulation of HSP72 differs between fast and slow muscles

  12. Polyphenols and Volatiles in Fruits of Two Sour Cherry Cultivars, Some Berry Fruits and Their Jams

    Directory of Open Access Journals (Sweden)

    Branka Levaj

    2010-01-01

    Full Text Available This paper reports about the content of polyphenols and volatiles in fresh fruits of two sour cherry cultivars (Marasca and Oblačinska, some berry fruits (strawberry Maya, raspberry Willamette and wild blueberry and the corresponding low sugar jams. Phenolic compounds (hydroxybenzoic and hydroxycinnamic acids, flavan 3-ols and flavonols were determined by high-performance liquid chromatography (HPLC. Those found in the fruits were also found in the jams. Jams contained lower amounts of polyphenols than fresh fuits, but their overall retention in jams was relatively high. Among fruits, sour cherry Marasca had the highest level of polyphenols, while sour cherry Marasca jam and raspberry Willamette jam had the highest level of polyphenols among jams. The major flavonoid in all investigated fruits, except in sour cherry Oblačinska, was (–-epicatechin. Sour cherry Marasca had the highest level of (–-epicatechin (95.75 mg/kg, and it also contained very high amounts of flavonols, derivatives of quercetin and kaempferol. Hydroxybenzoic acids (HBAs were not found in sour cherries Marasca and Oblačinska, but were found in berry fruits and jams. Phenolic compound (+-gallocatechin was found only in Marasca fruit and jam. Ellagic acid was found in the highest concentration in raspberry Willamette fruit and jam. Hydroxycinnamic acids (HCAs were found in all the investigated fruits, with the exception of a derivative of ferulic acid, which was not found in strawberry. Derivatives of caffeic, p-coumaric and chlorogenic acids were found in all the investigated fruits, with chlorogenic acid being the most abundant, especially in sour cherry Marasca. Volatiles were determined by gas chromatography (GC and expressed as the peak area of the identified compounds. All investigated volatiles of fresh fruit were also determined in the related jams with relatively high retention. Sour cherries Marasca and Oblačinska contained the same volatile compounds, but

  13. Spatio-temporal propagation of traffic jams in urban traffic networks

    OpenAIRE

    Jiang, Yinan; Kang, Rui; Li, Daqing; Guo, Shengmin; Havlin, Shlomo

    2017-01-01

    Since the first reported traffic jam about a century ago, traffic congestion has been intensively studied with various methods ranging from macroscopic to microscopic viewpoint. However, due to the population growth and fast civilization, traffic congestion has become significantly worse not only leading to economic losses, but also causes environment damages. Without understanding of jams spatio-temporal propagation behavior in a city, it is impossible to develop efficient mitigation strateg...

  14. High Speed Dim Air Target Detection Using Airborne Radar under Clutter and Jamming Effects

    OpenAIRE

    A. E. Almslmany; Q. S. Cao; Wang, C.Y.

    2015-01-01

    The challenging potential problems associated with using airborne radar in detection of high Speed Maneuvering Dim Target (HSMDT) are the highly noise, jamming and clutter effects. The problem is not only how to remove clutter and jamming as well as the range migration and Doppler ambiguity estimation problems due to high relative speed between the targets and airborne radar. Some of the recently published works ignored the range migration problems, while the others ignored the Doppler ambigu...

  15. Camouflage Traffic: Minimizing Message Delay for Smart Grid Applications Under Jamming

    Science.gov (United States)

    2015-01-16

    anti-islanding in the power engineering commu- nity [3], [28]. In this work, we use universal software radio peripheral ( USRP ) devices with GNU Radio...centralized management. Each IED’s routine traffic is one message of status update to the gateway every second. Both IEDs and the gateways use USRPs to...that a reactive jammer senses and jams such messages. Jamming attacks. We also set up a USRP -based jammer with operational bandwidth of 125 KHz. When

  16. A comparison of DDS and DRFM techniques in the generation of "smart noise" jamming waveforms

    OpenAIRE

    Watson, Charles Joffery

    1996-01-01

    Approved for public release; distribution is unlimited This thesis presents a comparison of the effectiveness of 'smart noise' jamming waveforms against advanced threat radars, which are generated using either Direct Digital Synthesis (DDS) or Digital RF Memory (DRFM) based support jamming. The challenge lies in the fact the modern radar employs advanced waveforms, ultralow sidelobe antennas, coherent sidelobe cancelers, and sidelobe blankers to inhibit signals entering through its sidelob...

  17. Investigation of damages induced by ITER-relevant heat loads during massive gas injections on Beryllium

    Directory of Open Access Journals (Sweden)

    B. Spilker

    2016-12-01

    Full Text Available Massive gas injections (MGIs will be used in ITER to mitigate the strong damaging effect of full performance plasma disruptions on the plasma facing components. The MGI method transforms the stored plasma energy to radiation that is spread across the vacuum vessel with poloidal and toroidal asymmetries. This work investigated the impact of MGI like heat loading on the first wall armor material beryllium. ITER-relevant power densities of 90-260MWm−2in combination with pulse durations of 5-10ms were exerted onto the S-65 grade beryllium specimens in the electron beam facility JUDITH 1. All tested loading conditions led to noticeable surface morphology changes and in the expected worst case scenario, a crater with thermally induced cracks with a depth of up to ∼340µm formed in the loaded area. The level of destruction in the loaded area was strongly dependent on the pulse number but also on the formation of beryllium oxide. The cyclic melting of beryllium could lead to an armor thinning mechanism under the presence of melt motion driving forces such as surface tension, magnetic forces, and plasma pressure.

  18. Heat-induced-radiolabeling and click chemistry: A powerful combination for generating multifunctional nanomaterials.

    Science.gov (United States)

    Yuan, Hushan; Wilks, Moses Q; El Fakhri, Georges; Normandin, Marc D; Kaittanis, Charalambos; Josephson, Lee

    2017-01-01

    A key advantage of nanomaterials for biomedical applications is their ability to feature multiple small reporter groups (multimodality), or combinations of reporter groups and therapeutic agents (multifunctionality), while being targeted to cell surface receptors. Here a facile combination of techniques for the syntheses of multimodal, targeted nanoparticles (NPs) is presented, whereby heat-induced-radiolabeling (HIR) labels NPs with radiometals and so-called click chemistry is used to attach bioactive groups to the NP surface. Click-reactive alkyne or azide groups were first attached to the nonradioactive clinical Feraheme (FH) NPs. Resulting "Alkyne-FH" and "Azide-FH" intermediates, like the parent NP, tolerated 89Zr labeling by the HIR method previously described. Subsequently, biomolecules were quickly conjugated to the radioactive NPs by either copper-catalyzed or copper-free click reactions with high efficiency. Synthesis of the Alkyne-FH or Azide-FH intermediates, followed by HIR and then by click reactions for biomolecule attachment, provides a simple and potentially general path for the synthesis of multimodal, multifunctional, and targeted NPs for biomedical applications.

  19. Heat-induced-radiolabeling and click chemistry: A powerful combination for generating multifunctional nanomaterials.

    Directory of Open Access Journals (Sweden)

    Hushan Yuan

    Full Text Available A key advantage of nanomaterials for biomedical applications is their ability to feature multiple small reporter groups (multimodality, or combinations of reporter groups and therapeutic agents (multifunctionality, while being targeted to cell surface receptors. Here a facile combination of techniques for the syntheses of multimodal, targeted nanoparticles (NPs is presented, whereby heat-induced-radiolabeling (HIR labels NPs with radiometals and so-called click chemistry is used to attach bioactive groups to the NP surface. Click-reactive alkyne or azide groups were first attached to the nonradioactive clinical Feraheme (FH NPs. Resulting "Alkyne-FH" and "Azide-FH" intermediates, like the parent NP, tolerated 89Zr labeling by the HIR method previously described. Subsequently, biomolecules were quickly conjugated to the radioactive NPs by either copper-catalyzed or copper-free click reactions with high efficiency. Synthesis of the Alkyne-FH or Azide-FH intermediates, followed by HIR and then by click reactions for biomolecule attachment, provides a simple and potentially general path for the synthesis of multimodal, multifunctional, and targeted NPs for biomedical applications.

  20. Caffeine Induces the Stress Response and Up-Regulates Heat Shock Proteins in Caenorhabditis elegans.

    Science.gov (United States)

    Al-Amin, Mohammad; Kawasaki, Ichiro; Gong, Joomi; Shim, Yhong-Hee

    2016-02-01

    Caffeine has both positive and negative effects on physiological functions in a dose-dependent manner. C. elegans has been used as an animal model to investigate the effects of caffeine on development. Caffeine treatment at a high dose (30 mM) showed detrimental effects and caused early larval arrest. We performed a comparative proteomic analysis to investigate the mode of action of high-dose caffeine treatment in C. elegans and found that the stress response proteins, heat shock protein (HSP)-4 (endoplasmic reticulum [ER] chaperone), HSP-6 (mitochondrial chaperone), and HSP-16 (cytosolic chaperone), were induced and their expression was regulated at the transcriptional level. These findings suggest that high-dose caffeine intake causes a strong stress response and activates all three stress-response pathways in the worms, including the ER-, mitochondrial-, and cytosolic pathways. RNA interference of each hsp gene or in triple combination retarded growth. In addition, caffeine treatment stimulated a food-avoidance behavior (aversion phenotype), which was enhanced by RNAi depletion of the hsp-4 gene. Therefore, up-regulation of hsp genes after caffeine treatment appeared to be the major responses to alleviate stress and protect against developmental arrest.

  1. Suppression of insolation heating induced by electromagnetic scatteringdue to fine spheres

    Science.gov (United States)

    Horie, J.; Mikada, H.; Goto, T.; Takekawa, J.; Manaka, Y.; Taniguchi, K.; Ashida, Y.

    2013-12-01

    The 2011 off the Pacific coast of Tohoku Earthquake, i.e., the greatest earthquake in the Japanese history, and the successive disaster at the Fukushima Daiichi Nuclear Power Plant have caused a fatal electric power shortage problem in summer in 2011. It is of key importance to reduce electricity demand and to save the energy. About one third of the total electricity demand at the peak consumption in summer is for the air-conditioning in the household and office sectors in Japan. It is, therefore, necessary to think deliberately of the reduction of electric power demand for air-conditioning. In fact, the temperature of materials rises when they are exposed to the sunlight (insolation heating) in particular in summer and the air-conditioning would become necessary for restoring the comfort in insolated housings. The energy for the air-conditioning is spent to pump out the heat changed in the materials of the insolated housings and would be proportional to the temperature to lower down. It is, therefore, clear that the reduction of the energy for the air-conditioning would strongly depend on relaxation of temperature rise or the insulation of insolated materials. Insolation heating could be suppressed when the materials are coated with paint admixed with fine silica spheres (insulating paint). By coating buildings' walls and roofs with such paint, the temperature of interior rooms could be kept lower without air-conditioning. These insulation effects are well known and have been utilized in the past, but have hardly been analyzed theoretically yet. Theoretical analysis would greatly enhance the effects of the suppression of insolation heating. In preceding studies, Ohkawa et al.(2009; 2011) and Mikada et al.(2011) focused on the electromagnetic wave scattering induced by fine spheres and developed the analytical method using superposition of scattered waves from each sphere (the first Born approximation), and indicated that the size of the spheres is one of the

  2. Heat shock-induced dissociation of TRF2 from telomeres does not initiate a telomere-dependent DNA damage response.

    Science.gov (United States)

    Petrova, Nadezhda V; Velichko, Artem K; Kantidze, Omar L; Razin, Sergey V

    2014-05-01

    Telomeric repeat binding factor 2 (TRF2) is a well-studied shelterin complex subunit that plays a major role in the protection of chomosome ends and the prevention of the telomere-associated DNA damage response. We show that heat shock induces the dissociation of TRF2 from telomeres in human primary and cancer cell cultures. TRF2 is not simply degraded in response to heat shock, but redistributed thoughout the nucleoplasm. This TRF2 depletion/redistribution does not initiate the DNA damage response at chomosome termini. © 2014 International Federation for Cell Biology.

  3. Measurement-induced operation of two-ion quantum heat machines

    Science.gov (United States)

    Chand, Suman; Biswas, Asoka

    2017-03-01

    We show how one can implement a quantum heat machine by using two interacting trapped ions, in presence of a thermal bath. The electronic states of the ions act like a working substance, while the vibrational mode is modelled as the cold bath. The heat exchange with the cold bath is mimicked by the projective measurement of the electronic states. We show how such measurement in a suitable basis can lead to either a quantum heat engine or a refrigerator, which undergoes a quantum Otto cycle. The local magnetic field is adiabatically changed during the heat cycle. The performance of the heat machine depends upon the interaction strength between the ions, the magnetic fields, and the measurement cost. In our model, the coupling to the hot and the cold baths is never switched off in an alternative fashion during the heat cycle, unlike other existing proposals of quantum heat engines. This makes our proposal experimentally realizable using current tapped-ion technology.

  4. Current Induced Heat Generation in Ferromagnet-Quantum Dot-Ferromagnet System

    Directory of Open Access Journals (Sweden)

    Lili Zhao

    2015-06-01

    Full Text Available We study the heat generation in ferromagnet-quantum dot-ferromagnet system by the non-equilibrium Green’s functions method. Heat generation under the influence of ferromagnet leads is very different compared with a system with normal metal leads. The significant effects in heat generation are caused by the polarization angle θ associated with the orientation of polarized magnetic moment of electron in the ferromagnetic terminals. From the study of heat generation versus source drain bias (Q-eV curves, we find that the heat generation decreases as θ increases from 0 to 0.7π. The heat generation versus gate voltage (Q-eVg curves also display interesting behavior with increasing polarization angle θ. Meanwhile, heat generation is influenced by the relative angle θ of magnetic moment in the ferromagnetic leads. These results will provide theories to this quantum dot system as a new material of spintronics.

  5. Moist and dry heating-induced changes in protein molecular structure, protein subfractions, and nutrient profiles in camelina seeds.

    Science.gov (United States)

    Peng, Quanhui; Khan, Nazir A; Wang, Zhisheng; Yu, Peiqiang

    2014-01-01

    The objectives of the present study were to investigate the nutritive value of camelina seeds (Camelina sativa L. Crantz) in ruminant nutrition and to use molecular spectroscopy as a novel technique to quantify the heat-induced changes in protein molecular structures in relation to protein digestive behavior in the rumen and intestine of dairy cattle. In this study, camelina seeds were used as a model for feed protein. The seeds were kept as raw (control) or heated in an autoclave (moist heating) or in an air-draft oven (dry heating) at 120°C for 60 min. The parameters evaluated were (1) chemical profiles, (2) Cornell Net Protein and Carbohydrate System protein subfractions, (3) nutrient digestibilities and estimated energy values, (4) in situ rumen degradation and intestinal digestibility, and (5) protein molecular structures. Compared with raw seeds, moist heating markedly decreased (52.73 to 20.41%) the content of soluble protein and increased (2.00 to 9.01%) the content of neutral detergent insoluble protein in total crude protein (CP). Subsequently, the rapidly degradable Cornell Net Protein and Carbohydrate System CP fraction markedly decreased (45.06 to 16.69% CP), with a concomitant increase in the intermediately degradable (45.28 to 74.02% CP) and slowly degradable (1.13 to 8.02% CP) fractions, demonstrating a decrease in overall protein degradability in the rumen. The in situ rumen incubation study revealed that moist heating decreased (75.45 to 57.92%) rumen-degradable protein and increased (43.90 to 82.95%) intestinal digestibility of rumen-undegradable protein. The molecular spectroscopy study revealed that moist heating increased the amide I-to-amide II ratio and decreased α-helix and α-helix-to-β-sheet ratio. In contrast, dry heating did not significantly change CP solubility, rumen degradability, intestinal digestibility, and protein molecular structures compared with the raw seeds. Our results indicated that, compared with dry heating, moist

  6. Hough Radar Detectors in Conditions of Intensive Pulse Jamming

    Directory of Open Access Journals (Sweden)

    Christo A. KABAKCHIEV

    2005-08-01

    Full Text Available We study in the present paper the radar, which can be considered as a part of a multi-sensor data fusion system. To improve the quality of the detection process, a detailed statistical analysis is performed and several detection algorithms are presented. These algorithms can be divided into two groups – conventional and ones using Hough transform. The benefits in the average detection threshold gained by Hough transform application are expressed as signal-to-noise ratio. The aim of this paper is to present and summarize the results described in other contributions and to consider some new ones. We assume that the target echo signal fluctuates according to Swerling models (Swerling I, II, III, the randomly arriving impulse interference is with a Poisson distribution of the probability for appearance and the amplitudes are with a Rayleigh distribution. The profits (losses are determined as a statistical estimation by means of the probability characteristics of both types of detectors, obtained in Matlab. The achieved results show that Hough transform is very effective in conditions of intensive pulse jamming.

  7. Soft Robotics Commercialization: Jamming Grippers from Research to Product

    Science.gov (United States)

    Cheng, Nadia; Fakhouri, Sami; Culley, Bill

    2016-01-01

    Abstract Recent work in the growing field of soft robotics has demonstrated a number of very promising technologies. However, to make a significant impact in real-world applications, these new technologies must first transition out of the laboratory through successful commercialization. Commercialization is perhaps the most critical future milestone facing the field of soft robotics today, and this process will reveal whether the apparent impact we now perceive has been appropriately estimated. Since 2012, Empire Robotics has been one of the first companies to attempt to reach this milestone through our efforts to commercialize jamming-based robotic gripper technology in a product called VERSABALL®. However, in spring 2016 we are closing our doors, having not been able to develop a sustainable business around this technology. This article presents some of the key takeaways from the technical side of the commercialization process and lessons learned that may be valuable to others. We hope that sharing this information will provide a frame of reference for technology commercialization that can help others motivate research directions and maximize research impact. PMID:28078197

  8. Rician MIMO Channel- and Jamming-Aware Decision Fusion

    Science.gov (United States)

    Ciuonzo, Domenico; Aubry, Augusto; Carotenuto, Vincenzo

    2017-08-01

    In this manuscript we study channel-aware decision fusion (DF) in a wireless sensor network (WSN) where: (i) the sensors transmit their decisions simultaneously for spectral efficiency purposes and the DF center (DFC) is equipped with multiple antennas; (ii) each sensor-DFC channel is described via a Rician model. As opposed to the existing literature, in order to account for stringent energy constraints in the WSN, only statistical channel information is assumed for the non-line-of sight (scattered) fading terms. For such a scenario, sub-optimal fusion rules are developed in order to deal with the exponential complexity of the likelihood ratio test (LRT) and impractical (complete) system knowledge. Furthermore, the considered model is extended to the case of (partially unknown) jamming-originated interference. Then the obtained fusion rules are modified with the use of composite hypothesis testing framework and generalized LRT. Coincidence and statistical equivalence among them are also investigated under some relevant simplified scenarios. Numerical results compare the proposed rules and highlight their jammingsuppression capability.

  9. A Geometric-Structure Theory for Maximally Random Jammed Packings.

    Science.gov (United States)

    Tian, Jianxiang; Xu, Yaopengxiao; Jiao, Yang; Torquato, Salvatore

    2015-11-16

    Maximally random jammed (MRJ) particle packings can be viewed as prototypical glasses in that they are maximally disordered while simultaneously being mechanically rigid. The prediction of the MRJ packing density ϕMRJ, among other packing properties of frictionless particles, still poses many theoretical challenges, even for congruent spheres or disks. Using the geometric-structure approach, we derive for the first time a highly accurate formula for MRJ densities for a very wide class of two-dimensional frictionless packings, namely, binary convex superdisks, with shapes that continuously interpolate between circles and squares. By incorporating specific attributes of MRJ states and a novel organizing principle, our formula yields predictions of ϕMRJ that are in excellent agreement with corresponding computer-simulation estimates in almost the entire α-x plane with semi-axis ratio α and small-particle relative number concentration x. Importantly, in the monodisperse circle limit, the predicted ϕMRJ = 0.834 agrees very well with the very recently numerically discovered MRJ density of 0.827, which distinguishes it from high-density "random-close packing" polycrystalline states and hence provides a stringent test on the theory. Similarly, for non-circular monodisperse superdisks, we predict MRJ states with densities that are appreciably smaller than is conventionally thought to be achievable by standard packing protocols.

  10. Soft Robotics Commercialization: Jamming Grippers from Research to Product.

    Science.gov (United States)

    Amend, John; Cheng, Nadia; Fakhouri, Sami; Culley, Bill

    2016-12-01

    Recent work in the growing field of soft robotics has demonstrated a number of very promising technologies. However, to make a significant impact in real-world applications, these new technologies must first transition out of the laboratory through successful commercialization. Commercialization is perhaps the most critical future milestone facing the field of soft robotics today, and this process will reveal whether the apparent impact we now perceive has been appropriately estimated. Since 2012, Empire Robotics has been one of the first companies to attempt to reach this milestone through our efforts to commercialize jamming-based robotic gripper technology in a product called VERSABALL®. However, in spring 2016 we are closing our doors, having not been able to develop a sustainable business around this technology. This article presents some of the key takeaways from the technical side of the commercialization process and lessons learned that may be valuable to others. We hope that sharing this information will provide a frame of reference for technology commercialization that can help others motivate research directions and maximize research impact.

  11. ELM-free and inter-ELM divertor heat flux broadening induced by edge harmonics oscillation in NSTX

    Science.gov (United States)

    Gan, K. F.; Ahn, J.-W.; Gray, T. K.; Zweben, S. J.; Fredrickson, E. D.; Scotti, F.; Maingi, R.; Park, J.-K.; Canal, G. P.; Soukhanovskii, V. A.; Mclean, A. G.; Wirth, B. D.

    2017-12-01

    A new n  =  1 dominated edge harmonic oscillation (EHO) has been found in NSTX. The new EHO, rotating toroidally in the counter-current direction and the opposite direction of the neutral beam, was observed during certain inter-ELM and ELM-free periods of H-mode operation. This EHO is associated with a significant broadening of the integral heat flux width ({λ\\operatorname{int}} ) by up to 150%, and a decrease in the divertor peak heat flux by  >60%. An EHO induced filament was also observed by the gas puff imaging diagnostic. The toroidal rotating filaments could change the edge magnetic topology resulting in toroidal rotating strike point splitting and heat flux broadening. Experimental result of the counter current rotation of strike points splitting is consistent with the counter-current EHO.

  12. Hydrogen-induced cold cracking in heat-affected zone of low-carbon high-strength steel

    Science.gov (United States)

    Lan, Liangyun; Kong, Xiangwei; Hu, Zhiyong; Qiu, Chunlin

    2014-12-01

    The Y-groove cracking test by submerged arc welding was employed to study the susceptibility of a low-carbon high-strength steel to hydrogen-induced cold cracking (HICC). The morphology of hydrogen cracks was observed using an electron probe microscope. The results showed that the heat-affected zone (HAZ) has a higher susceptibility to HICC than the weld metal and that increasing heat input can improve the HICC resistance of the weldment. The intergranular microcracking is the main HICC mode at the lowest heat input condition, accompanied with some transgranular microcracks attached to complex inclusions. In combination with phase transformation behaviour in sub-zones, the effect of the phase transformation sequence is proposed to try to illustrate the fact that the fine-grained HAZ has higher probability of hydrogen cracking than the coarse-grained HAZ owing to the occurrence of hydrogen enrichment in the fine-grained HAZ after the transformation.

  13. Numerical simulations on conformable laser-induced interstitial thermotherapy through combined use of multi-beam heating and biodegradable nanoparticles.

    Science.gov (United States)

    Zhang, Jie; Jin, Chao; He, Zhi-Zhu; Liu, Jing

    2014-07-01

    Clinically, precisely heating and thus completely ablating diseased tumor tissue through laser beam is still facing many technical challenges. In this study, numerical simulation of a conformal heating modality based on multi-beam laser along with biodegradable magnesium nanoparticles (Mg-NPs) was put forward to treat liver tumor with large size or irregular shape. Further, a Gaussian-like distribution was proposed to investigate the influence of Mg-NP deposition on the nanoenhanced laser-induced interstitial thermotherapy (LITT). A temperature feedback system was adopted to control the temperature range to avoid overheating. To preliminarily validate the heating enhancement induced by the applied multi-beam laser and Mg-NPs, a conceptual experiment was performed. Both theoretical simulation and experimental measurements demonstrated that multi-beam laser with Mg-NPs could improve efficiency in the conformal heating of tumors with irregular shape or large size. In addition, the distribution and content of Mg-NPs produced significant impact on thermotherapy: (1) The adjustable parameter σ in the Gaussian-like distribution could reflect various practical situations and diffusivities of Mg-NPs; (2) under the premise of the same concentration of Mg-NPs and short time to heat a small-sized target, the whole liver tumor containing Mg-NPs could not improve the efficiency as the nanoparticles limited the photons to be absorbed only around the fibers, while liver tumor partially containing Mg-NPs could improve the thermotherapy efficiency up to 20 %; and (3) the addition of Mg-NPs was rather beneficial for realizing a conformal heating as the residual thermal energy was much less than that without Mg-NPs. This study suggests a feasible and promising modality for planning a high-performance LITT in future clinics.

  14. Pressure effects on the structure, kinetic, and thermodynamic properties of heat-induced aggregation of protein studied by FT-IR spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Taniguchi, Y [Applied Chemistry Department, Ritsumeikan University, Kusatsu, Shiga 525-8577 (Japan); Okuno, A [Research Department 3, Central Research, Bridgestone Co. Kodaira, Tokyo 187-8531 (Japan); Kato, M, E-mail: taniguti@sk.ritsumei.ac.j [Pharmaceutical Sciences Department, Ritsumeikan University, Kusatsu, Shiga 525-8577 (Japan)

    2010-03-01

    Pressure can retrain the heat-induced aggregation and dissociate the heat-induced aggregates. We observed the aggregation-preventing pressure effect and the aggregates-dissociating pressure effect to characterize the heat-induced aggregation of equine serum albumin (ESA) by FT-IR spectroscopy. The results suggest the {alpha}-helical structure collapses at the beginning of heat-induced aggregation through the swollen structure, and then the rearrangement of structure to the intermolecular {beta}-sheet takes place through partially unfolded structure. We determined the activation volume for the heat-induced aggregation ({Delta}V'' = +93 ml/mol) and the partial molar volume difference between native state and heat-induced aggregates ({Delta}V=+32 ml/mol). This positive partial molar volume difference suggests that the heat-induced aggregates have larger internal voids than the native structure. Moreover, the positive volume change implies that the formation of the intermolecular {beta}-sheet is unfavorable under high pressure.

  15. Quantum heat engine power can be increased by noise-induced coherence.

    Science.gov (United States)

    Scully, Marlan O; Chapin, Kimberly R; Dorfman, Konstantin E; Kim, Moochan Barnabas; Svidzinsky, Anatoly

    2011-09-13

    Laser and photocell quantum heat engines (QHEs) are powered by thermal light and governed by the laws of quantum thermodynamics. To appreciate the deep connection between quantum mechanics and thermodynamics we need only recall that in 1901 Planck introduced the quantum of action to calculate the entropy of thermal light, and in 1905 Einstein's studies of the entropy of thermal light led him to introduce the photon. Then in 1917, he discovered stimulated emission by using detailed balance arguments. Half a century later, Scovil and Schulz-DuBois applied detailed balance ideas to show that maser photons were produced with Carnot quantum efficiency (see Fig. 1A). Furthermore, Shockley and Quiesser invoked detailed balance to obtain the efficiency of a photocell illuminated by "hot" thermal light (see Fig. 2A). To understand this detailed balance limit, we note that in the QHE, the incident light excites electrons, which can then deliver useful work to a load. However, the efficiency is limited by radiative recombination in which the excited electrons are returned to the ground state. But it has been proven that radiatively induced quantum coherence can break detailed balance and yield lasing without inversion. Here we show that noise-induced coherence enables us to break detailed balance and get more power out of a laser or photocell QHE. Surprisingly, this coherence can be induced by the same noisy (thermal) emission and absorption processes that drive the QHE (see Fig. 3A). Furthermore, this noise-induced coherence can be robust against environmental decoherence.Fig. 1.(A) Schematic of a laser pumped by hot photons at temperature T(h) (energy source, blue) and by cold photons at temperature T(c) (entropy sink, red). The laser emits photons (green) such that at threshold the laser photon energy and pump photon energy is related by Carnot efficiency (4). (B) Schematic of atoms inside the cavity. Lower level b is coupled to the excited states a and β. The laser power

  16. Heat-induced gelation mechanism of blood plasma modulated by cysteine.

    Science.gov (United States)

    Saguer, E; Alvarez, P; Fort, N; Espigulé, E; Parés, D; Toldrà, M; Carretero, C

    2015-03-01

    This work aims to determine changes at molecular level of plasma proteins provoked by adding cysteine (Cys, 0.025% to 0.35% w/v) as a reducing agent and their relationship with the heat-induced gel properties obtained when subsequently the solutions were submitted to a thermal treatment. Results show that adding Cys to plasma solutions at concentrations ≥0.15% actually entails modifications in the secondary structure of their main proteins, that is, serum albumin-α-helix rich-and globulin fraction-β-sheet rich. Basically, a reduction of the intensity of the infrared (IR) bands assigned to both structures takes place concomitant to an increase of extended structures that seem to act as intermediates for the subsequent protein aggregation process through nonnative intermolecular β-sheets. Cleavage of disulfide bonds is also evidenced at Cys concentrations ≥0.15% by nonreducing sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), with the effects being directly proportional to Cys concentration. However, beneficial effects on gel hardness are gradually obtained at Cys concentrations ≤0.15%, that is, when the effects at molecular level are at most just budding, while not more improvements on this textural parameter are obtained at higher Cys concentrations. By contrast, water retention capacity is gradually diminishing as Cys concentration increases, but with a significant reduction only obtained at the highest tested concentration. These results suggest a negative effect of Cys on gel microstructure at high concentrations, which probably can be attributed to protein aggregation taking place at room temperature. © 2015 Institute of Food Technologists®

  17. Coacervation of β-conglycinin, glycinin and isoflavones induced by propylene glycol alginate in heated soymilk.

    Science.gov (United States)

    Hsiao, Yu-Hsuan; Lu, Chun-Ping; Kuo, Meng-I; Hsieh, Jung-Feng

    2016-06-01

    This study investigated the propylene glycol alginate (PGA)-induced coacervation of β-conglycinin (7S), glycinin (11S) and isoflavones in heated soymilk. The addition of 0.9% PGA caused 7S, 11S, daidzein and genistein to coacervate following a 1h incubation period. SDS-PAGE showed that the protein bands corresponding to the 7S α', 7S α, 7S β, 11S A3, and 11S acidic subunits and the 11S basic proteins in the soymilk supernatant fraction (SSF) decreased to 37.7 ± 12.7%, 24.7 ± 3.9%, 4.9 ± 1.8%, 8.5 ± 2.7%, 18.1 ± 1.8% and 6.0 ± 1.6%, respectively. In addition, isoflavones including daidzein and genistein were also coacervated from the SSF into the soymilk pellet fraction (SPF) following incubation with 0.9% PGA for 1h. The amounts of daidzein and genistein in the SSF decreased to 8.6 ± 1.6% and 2.0 ± 1.0%, respectively. HPLC analysis suggested that daidzein and genistein were bound to the 7S and 11S proteins. These results suggested that daidzein and genistein were co-precipitated with the 7S and 11S proteins into the SPF by 0.9% PGA. Our results demonstrated that PGA is a potent coagulant for the coacervation of 7S, 11S, daidzein and genistein. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Heat shock protein 70 and sex steroid receptors in the follicular structures of induced ovarian cysts.

    Science.gov (United States)

    Salvetti, N R; Baravalle, C; Mira, G A; Gimeno, E J; Dallard, B E; Rey, F; Ortega, H H

    2009-10-01

    The purpose of this study was to estimate the expression and relative amounts of estrogen (ER) and progesterone receptors (PR) and their isoforms as well as heat shock protein 70 (HSP70) in ovaries of rats with induced cystic ovarian disease (COD). Primary, secondary, tertiary, atretic and cystic follicles were evaluated by immunohistochemistry and total ovarian proteins were analyzed by Western blot. In the granulosa layer, growing and cystic follicles in the treated group have a higher expression of ERalpha than growing follicles of control individuals. In the theca interna layer, tertiary follicles presented a significantly higher expression of ERalpha in the treated group. An increase in total ERalpha protein was detected in the treated group. Granulosa cells of all growing, atretic and cystic follicles show a lower expression of ERbeta in animals with COD, and the total protein expression of ERbeta was lower in this group. The expression of PR was lower in the granulosa cell layer of tertiary and cystic follicles in treated animals, and theca interna layer had less intense immunostaining in this group. Although there were no differences in the expression of PR-B by Western blotting, the expression of PR-A was higher and the expression of PR-C was smaller in the treated group. An intense HSP70 immunostaining was observed in the cells of cystic follicles. By Western blotting, higher protein expression of HSP70 was detected in the ovarian samples of the control group than those of the treated ones. Ovaries of animals with COD exhibited an altered steroid receptor expression and subtype balance as compared with control animals, and an increase in HSP70 immunoexpression.

  19. Chelate-free metal ion binding and heat-induced radiolabeling of iron oxide nanoparticles.

    Science.gov (United States)

    Boros, Eszter; Bowen, Alice M; Josephson, Lee; Vasdev, Neil; Holland, Jason P

    2015-01-01

    A novel reaction for chelate-free, heat-induced metal ion binding and radiolabeling of ultra-small paramagnetic iron oxide nanoparticles (USPIOs) has been established. Radiochemical and non-radioactive labeling studies demonstrated that the reaction has a wide chemical scope and is applicable to p-, d- and f-block metal ions with varying ionic sizes and formal oxidation states from 2+ to 4+. Radiolabeling studies found that 89Zr-Feraheme (89Zr-FH or 89Zr-ferumoxytol) can be isolated in 93 ± 3% radiochemical yield (RCY) and >98% radiochemical purity using size-exclusion chromatography. 89Zr-FH was found to be thermodynamically and kinetically stable in vitro using a series of ligand challenge and plasma stability tests, and in vivo using PET/CT imaging and biodistribution studies in mice. Remarkably, ICP-MS and radiochemistry experiments showed that the same reaction conditions used to produce 89Zr-FH can be employed with different radionuclides to yield 64Cu-FH (66 ± 6% RCY) and 111In-FH (91 ± 2% RCY). Electron magnetic resonance studies support a mechanism of binding involving metal ion association with the surface of the magnetite crystal core. Collectively, these data suggest that chelate-free labeling methods can be employed to facilitate clinical translation of a new class of multimodality PET/MRI radiotracers derived from metal-based nanoparticles. Further, this discovery is likely to have broader implications in drug delivery, metal separation science, ecotoxicology of nanoparticles and beyond.

  20. Heat-induced irreversible denaturation of the camelid single domain VHH antibody is governed by chemical modifications.

    Science.gov (United States)

    Akazawa-Ogawa, Yoko; Takashima, Mizuki; Lee, Young-Ho; Ikegami, Takahisa; Goto, Yuji; Uegaki, Koichi; Hagihara, Yoshihisa

    2014-05-30

    The variable domain of camelid heavy chain antibody (VHH) is highly heat-resistant and is therefore ideal for many applications. Although understanding the process of heat-induced irreversible denaturation is essential to improve the efficacy of VHH, its inactivation mechanism remains unclear. Here, we showed that chemical modifications predominantly governed the irreversible denaturation of VHH at high temperatures. After heat treatment, the activity of VHH was dependent only on the incubation time at 90 °C and was insensitive to the number of heating (90 °C)-cooling (20 °C) cycles, indicating a negligible role for folding/unfolding intermediates on permanent denaturation. The residual activity was independent of concentration; therefore, VHH lost its activity in a unimolecular manner, not by aggregation. A VHH mutant lacking Asn, which is susceptible to chemical modifications, had significantly higher heat resistance than did the wild-type protein, indicating the importance of chemical modifications to VHH denaturation. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  1. Climate change-induced heat risks for migrant populations working at brick kilns in India: a transdisciplinary approach.

    Science.gov (United States)

    Lundgren-Kownacki, Karin; Kjellberg, Siri M; Gooch, Pernille; Dabaieh, Marwa; Anandh, Latha; Venugopal, Vidhya

    2017-11-30

    During the summer of 2015, India was hit by a scorching heat wave that melted pavements in Delhi and caused thousands of deaths, mainly among the most marginalized populations. One such group facing growing heat risks from both occupational and meteorological causes are migrant brick kiln workers. This study evaluates both current heat risks and the potential future impacts of heat caused by climate change, for the people working at brick kilns in India. A case study of heat stress faced by people working at brick kilns near Chennai, India, is the anchor point around which a transdisciplinary approach was applied. Around Chennai, the situation is alarming since occupational heat exposure in the hot season from March to July is already at the upper limits of what humans can tolerate before risking serious impairment. The aim of the study was to identify new pathways for change and soft solutions by both reframing the problem and expanding the solution space being considered in order to improve the quality of life for the migrant populations at the brick kilns. Technical solutions evaluated include the use of sun-dried mud bricks and other locally "appropriate technologies" that could mitigate the worsening of climate change-induced heat. Socio-cultural solutions discussed for empowering the people who work at the brick kilns include participatory approaches such as open re-localization, and rights-based approaches including the environmental sustainability and the human rights-based approach framework. Our analysis suggests that an integrative, transdisciplinary approach could incorporate a more holistic range of technical and socio-culturally informed solutions in order to protect the health of people threatened by India's brick kiln industry.

  2. Isolation and characterization of the main small heat shock proteins induced in tomato pericarp by thermal treatment.

    Science.gov (United States)

    Polenta, Gustavo A; Calvete, Juan J; González, Claudia B

    2007-12-01

    In recent years, heat treatment has been used to prevent the development of chilling injury in fruits and vegetables. The acquired tolerance to chilling seen in treated fruit is related to the accumulation of heat shock proteins (HSPs). The positive effect of heat treatment has generally been verified for only a narrow range of treatment intensities and more reliable methods of determining optimal conditions are therefore needed. In this regard, quantitation of HSPs would seem to be an interesting tool for monitoring purposes. As a step toward the development of analytical methodology, the objective of this study was the isolation and characterization of relevant HSPs from plant tissues. Tomato fruits were exposed to a temperature of 38 degrees C for 0, 3, 20 and 27 h, and protein extracts from pericarp were analysed using SDS/PAGE. Analysis revealed the appearance of an intense 21 kDa protein band in treated samples. IEF of this band showed the presence of four major proteins (HSPC1, HSPC2, HSPC3 and HSPC4) with similar pI values. A monospecific polyclonal antiserum was raised in rabbits against purified HSPC1 protein, which cross-reacted with other small heat shock proteins. The major proteins were characterized by MS/MS analysis of tryptic peptides, all having blocked N-termini. The antiserum obtained proved suitable for detecting increased amounts of small heat shock proteins in tomatoes and grapefruits subjected to heat treatment for 24 and 48 h; these treatments were successful in preventing the development of chilling injury symptoms during cold storage. Our data are valuable for the future development of analytical methods to evaluate the optimal protection induced by heat treatment in different fruits.

  3. Climate change-induced heat risks for migrant populations working at brick kilns in India: a transdisciplinary approach

    Science.gov (United States)

    Lundgren-Kownacki, Karin; Kjellberg, Siri M.; Gooch, Pernille; Dabaieh, Marwa; Anandh, Latha; Venugopal, Vidhya

    2017-11-01

    During the summer of 2015, India was hit by a scorching heat wave that melted pavements in Delhi and caused thousands of deaths, mainly among the most marginalized populations. One such group facing growing heat risks from both occupational and meteorological causes are migrant brick kiln workers. This study evaluates both current heat risks and the potential future impacts of heat caused by climate change, for the people working at brick kilns in India. A case study of heat stress faced by people working at brick kilns near Chennai, India, is the anchor point around which a transdisciplinary approach was applied. Around Chennai, the situation is alarming since occupational heat exposure in the hot season from March to July is already at the upper limits of what humans can tolerate before risking serious impairment. The aim of the study was to identify new pathways for change and soft solutions by both reframing the problem and expanding the solution space being considered in order to improve the quality of life for the migrant populations at the brick kilns. Technical solutions evaluated include the use of sun-dried mud bricks and other locally "appropriate technologies" that could mitigate the worsening of climate change-induced heat. Socio-cultural solutions discussed for empowering the people who work at the brick kilns include participatory approaches such as open re-localization, and rights-based approaches including the environmental sustainability and the human rights-based approach framework. Our analysis suggests that an integrative, transdisciplinary approach could incorporate a more holistic range of technical and socio-culturally informed solutions in order to protect the health of people threatened by India's brick kiln industry.

  4. The C-terminal region of alpha-crystallin: involvement in protection against heat-induced denaturation

    Science.gov (United States)

    Takemoto, L.; Emmons, T.; Horwitz, J.; Spooner, B. S. (Principal Investigator)

    1993-01-01

    Recent studies have demonstrated that the alpha-crystallins can protect other proteins against heat-induced denaturation and aggregation. To determine the possible involvement of the C-terminal region in this activity, the alpha-crystallins were subjected to limited tryptic digestion, and the amount of cleavage from the N-terminal and C-terminal regions of the alpha-A and alpha-B crystallin chains was assessed using antisera specific for these regions. Limited tryptic digestion resulted in cleavage only from the C-terminal region of alpha-A crystallin. This trypsin-treated alpha-A crystallin preparation showed a decreased ability to protect proteins from heat-induced aggregation using an in vitro assay. Together, these results demonstrate that the C-terminal region of alpha-A crystallin is important for its ability to protect against heat-induced aggregation, which is consistent with the hypothesis that post-translational changes that are known to occur at the C-terminal region may have significant effects on the ability of alpha-A crystallin to protect against protein denaturation in vivo.

  5. Study on shear-induced thermal conductivity for heat transfer enhancement with non-Newtonian viscoelastic fluids

    Science.gov (United States)

    Lee, Dong-Ryul; Yoon, Hyun-Joong

    2013-09-01

    Shear-induced viscosity and thermal conductivity measurements were performed for viscoelastic fluids. This research was also designed to investigate the extent to which the thermal conductivity of viscoelastic fluids is affected by fluid motion under conditions in which it is known that the viscous properties undergo significant changes, and then the effect of the shear-induced thermal conductivity measured on the convective heat transfer enhancement for a heat exchanger system. It was also found experimentally that the thermal conductivity increased with shear rate for two polyacrylamide solutions of 1000 and 2000 wppm with order of 23%-43% and 17%-21%, respectively, depending on temperature (20-50 °C). The increase in the thermal conductivity with a shear rate was greater for lower concentration polyacrylamide solutions than for higher concentration ones, with a difference of 8%-22% depending on temperature range (20-50 °C). The convective heat transfer enhancement with the shear-induced thermal conductivity in the infinite rectangular duct was of the order of 41%-74% and 41%-52% over the entire temperature range (20-50 °C) of the two polyacrylamide solutions of 1000 and 2000 wppm, respectively.

  6. Robust multiple frequency multiple power localization schemes in the presence of multiple jamming attacks.

    Directory of Open Access Journals (Sweden)

    Ahmed Abdulqader Hussein

    Full Text Available Localization of the wireless sensor network is a vital area acquiring an impressive research concern and called upon to expand more with the rising of its applications. As localization is gaining prominence in wireless sensor network, it is vulnerable to jamming attacks. Jamming attacks disrupt communication opportunity among the sender and receiver and deeply impact the localization process, leading to a huge error of the estimated sensor node position. Therefore, detection and elimination of jamming influence are absolutely indispensable. Range-based techniques especially Received Signal Strength (RSS is facing severe impact of these attacks. This paper proposes algorithms based on Combination Multiple Frequency Multiple Power Localization (C-MFMPL and Step Function Multiple Frequency Multiple Power Localization (SF-MFMPL. The algorithms have been tested in the presence of multiple types of jamming attacks including capture and replay, random and constant jammers over a log normal shadow fading propagation model. In order to overcome the impact of random and constant jammers, the proposed method uses two sets of frequencies shared by the implemented anchor nodes to obtain the averaged RSS readings all over the transmitted frequencies successfully. In addition, three stages of filters have been used to cope with the replayed beacons caused by the capture and replay jammers. In this paper the localization performance of the proposed algorithms for the ideal case which is defined by without the existence of the jamming attack are compared with the case of jamming attacks. The main contribution of this paper is to achieve robust localization performance in the presence of multiple jamming attacks under log normal shadow fading environment with a different simulation conditions and scenarios.

  7. Heat-induced chemical and color changes of extractive-free Black Locust (Rosinia Pseudoacacia) wood

    Science.gov (United States)

    Yao Chen; Jianmin Gao; Yongming Fan; Mandla A. Tshabalala; Nicole M. Stark

    2012-01-01

    To investigate chemical and color changes of the polymeric constituents of black locust (Robinia pseudoacacia) wood during heat treatment, extractive-free wood flour was conditioned to 30% initial moisture content (MC) and heated for 24 h at 120 °C in either an oxygen or nitrogen atmosphere. The color change was measured using the CIELAB color system. Chemical changes...

  8. Induced Levels of Heat Shock Proteins in dnaK mutants of Lactococcus lactis

    DEFF Research Database (Denmark)

    Koch, Birgit; Hammer, Karin; Vogensen, Finn K.

    1998-01-01

    RNA levels which indicate that DnaK could be involved in the regulation of the heat shock response in Lactococcus lactis. In Bacillus subtilis it has been found by Mogk,A., G.Homouth, C. Scholz, L. Kim, F.X. Schmid, and W. Schumann. 1997. EMBO J. 16: 4579-4590, that the activity of the heat shock repressor...

  9. Hsp70 protects mitotic cells against heat-induced centrosome damage and division abnormalities

    NARCIS (Netherlands)

    Hut, HMJ; Kampinga, HH; Sibon, OCM

    The effect of heat shock on centrosomes has been mainly studied in interphase cells. Centrosomes play a key role in proper segregation of DNA during mitosis. However, the direct effect and consequences of heat shock on mitotic cells and a possible cellular defense system against proteotoxic stress

  10. Salinization in a stratified aquifer induced by heat transfer from well casings

    NARCIS (Netherlands)

    van Lopik, J.H.; Hartog, N.; Zaadnoordijk, Willem Jan; Cirkel, D. Gijsbert; Raoof, A.

    2015-01-01

    The temperature inside wells used for gas, oil and geothermal energy production, as well as steam injection, is in general significantly higher than the groundwater temperature at shallower depths. While heat loss from these hot wells is known to occur, the extent to which this heat loss may result

  11. Heating of coronal plasma by anomalous current dissipation. [induced by solar magnetic flux

    Science.gov (United States)

    Rosner, R.; Golub, L.; Coppi, B.; Vaiana, G. S.

    1978-01-01

    It is shown that there exist heating mechanisms which connect the observed radiative properties of the inner corona in a simple way to the underlying solar magnetic field. The mechanisms considered involve the generation and consequent dissipation of coronal currents. It is argued that the spatially and temporally inhomogeneous nature of the erupting solar magnetic field is an essential element of coronal heating. Unlike heating theories conceived in the context of the 'homogeneous' corona, this class of current heating models incorporates the observed stochastic coronal structuring at the onset, and does not view it as a complication of an otherwise straightforward model. Attention is given to the generation of coronal currents, the flux-tube emergence, the gradual growth and decay of active regions, the energetics of current dissipation, current sheath geometry and heat transport, and anomalous current dissipation.

  12. Polarization reversal induced by heating-cooling cycles in MgO doped lithium niobate crystals

    Science.gov (United States)

    Shur, V. Ya.; Mingaliev, E. A.; Lebedev, V. A.; Kuznetsov, D. K.; Fursov, D. V.

    2013-05-01

    Polarization reversal during heating-cooling cycles was investigated in MgO doped lithium niobate (MgO:LN) crystal using piezoresponse force microscopy. The essential dependence of the domain structure evolution scenario on the maximal temperature in the cycle has been revealed experimentally. It has been shown that the heating of the engineered domain matrix from room temperature to 85 °C leads to light size reduction of the isolated domains at the matrix edges, whereas the heating to 170 °C leads to essential reduction of the domain size. The opposite strong effect of the domain formation and growth during cooling after pulse heating have been revealed in single domain MgO:LN. The simulation of the time dependence of the pyroelectric field during heating-cooling cycle allowed to reveal the temperature hysteresis and to explain all observed effects taking into account the temperature dependence of the bulk conductivity.

  13. Modeling coupled thermal-mechanical processes of frozen soil induced by borehole heat exchanger

    Science.gov (United States)

    Shao, H.

    2015-12-01

    To utilize the shallow geothermal energy, heat pumps are often coupled with Borehole Heat Exchangers (BHE) to provide heating and cooling for buildings. In cold regions, soil freezing around the BHE is a potential problem which will dramatically influence the underground soil temperature distribution, subsequently the inlet and outlet refrigerant temperature of the BHE, and finally the efficiency of the heat pump. In this study, a numerical model has been developed to simulate the coupled temperature evolution both inside the BHE, and the propagating freezing front in the surrounding soil. The coupled model was validated against analytical solutions and experimental data. The influence of the freezing process on the overall system performance is investigated by comparing one long BHE configuration without freezing and another short one with latent heat from the frozen groundwater. It is found that when freezing happens, the coefficient of performance (COP) of the heat pump will decrease by around 0.5, leading to more electricity consumption. Furthermore, analysis of the simulation result reveals that the exploitation of latent heat through groundwater freezing is only economically attractive if electricity price is low and interest rate high, and it is not the case is most European countries.

  14. Dietary zinc may attenuate heat-induced testicular oxidative stress in mice via up-regulation of Cu-Zn SOD.

    Science.gov (United States)

    Cao, Y; Li, Y S; Li, Z J; Wang, F; Li, C M

    2015-12-11

    Zinc (Zn) is important for male mammalian reproduction. In this study, we sought to clarify the role of Zn in heat-induced testicular damage in mice. Eighteen mice were divided into either control (con), heat (heat) and heat plus Zn (H+Zn) treatment groups, and fed diets containing 60 (con and heat groups) or 300 (H+Zn group) mg/kg Zn sulfate for one month. Mice in the con group were then maintained at 25°C, while mice in heat and H+Zn groups were exposed to 40°C for 2 h daily, for eight days. Mouse testes and serum from each animal were analyzed. Zinc levels in serum and testes were positively correlated to Zn feed concentrations. Mice in the heat group had higher testes index than those in the other two groups (7.22 ± 0.75, heat; 4.92 ± 0.20, con; 4.80 ± 0.30 mg/g, H+Zn; P Cu-Zn superoxide dismutase (SOD) level differed between heat and H+Zn groups (14.04 ± 0.74 versus 18.27 ± 1.53 U/mg protein; P Cu-Zn SOD protein expression levels were significantly lower in the heat than in the control group (0.30 ± 0.11 versus 1.22 ± 0.13; P Cu-Zn SOD, to attenuate testicular oxidative stress induced by heat exposure.

  15. Epigenetic Changes are Associated with Programmed Cell Death Induced by Heat Stress in Seedling Leaves of Zea mays.

    Science.gov (United States)

    Wang, Pu; Zhao, Lin; Hou, Haoli; Zhang, Hao; Huang, Yan; Wang, Yapei; Li, Hui; Gao, Fei; Yan, Shihan; Li, Lijia

    2015-05-01

    Histone modification plays a crucial role in regulation of chromatin architecture and function, responding to adverse external stimuli. However, little is known about a possible relationship between epigenetic modification and programmed cell death (PCD) in response to environmental stress. Here, we found that heat stress induced PCD in maize seedling leaves which was characterized by chromatin DNA laddering and DNA strand breaks detected by a terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) test. The activities of the reactive oxygen species (ROS)-related enzymes superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) were progressively increased over time in the heat-treated seedlings. However, the concentration of H2O2 remained at relatively lower levels, while the concentration of superoxide anion ([Formula: see text]) was increased, accompanied by the occurrence of higher ion leakage rates after heat treatment. The total acetylation levels of histones H3K9, H4K5 and H3 were significantly increased, whereas the di-methylation level of histone H3K4 was unchanged and the di-methylation level of histone H3K9 was decreased in the seedling leaves exposed to heat stress compared with the control seedlings, accompanied by increased nucleolus size indicative of chromatin decondensation. Furthermore, treatment of seedlings with trichostatin A (TSA), which always results in genomic histone hyperacetylation, caused an increase in the [Formula: see text] level within the cells. The results suggested that heat stress persistently induced [Formula: see text], leading to PCD in association with histone modification changes in the maize leaves. © The Author 2015. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  16. Investigation of Heat Transfer in Mini Channels using Planar Laser Induced Fluorescence

    DEFF Research Database (Denmark)

    Bøgild, Morten Ryge; Poulsen, Jonas Lundsted; Rath, Emil Zacho

    2012-01-01

    In this paper an experimental investigation of the heat transfer in mini channels with a hydraulic diameter of 889 m is conducted. The method used is planar laser induceduorescence (PLIF), which uses the principle of laser excitation of rhodamine B in water. The goal of this study is to validate...... the applicability of PLIF to determine the convective heat transfer coecient in mini channels against conventional correlations of the convective heat transfer coecient. The applicability of the conventional theory in micro and mini channels has been discussed by several researchers, but to the authors knowledge...

  17. Vibration-induced coherence enhancement of the performance of a biological quantum heat engine.

    Science.gov (United States)

    Chen, Hong-Bin; Chiu, Pin-Yi; Chen, Yueh-Nan

    2016-11-01

    Photosynthesis has been a long-standing research interest due to its fundamental importance. Recently, studies on photosynthesis processes also have inspired attention from a thermodynamical aspect when considering photosynthetic apparatuses as biological quantum heat engines. Quantum coherence is shown to play a crucial role in enhancing the performance of these quantum heat engines. Based on the experimentally reported structure, we propose a quantum heat engine model with a non-Markovian vibrational mode. We show that one can obtain a performance enhancement easily for a wide range of parameters in the presence of the vibrational mode. Our results provide insights into the photosynthetic processes and a design principle mimicking natural organisms.

  18. Effect of indomethacin on hyperthermia induced by heat stress in broiler chickens

    Science.gov (United States)

    Furlan, R. L.; Macari, M.; Malheiros, E. B.; Secato, E. R.; Guerreiro, J. R.

    An investigation was carried out to verify whether the heat stress hyperthermia response of broilers is prostaglandin-dependent. Male broiler chickens of the Hubbard-Petterson strain, aged 35-49 days, were used. Chickens were injected with indomethacin (1 mg/kg intraperitoneally ) 15 min before or 2 h after heat exposure (at 35°C for 4 h), and rectal temperature was measured before injection and up to 4 h thereafter. Birds were separated into two groups with and without access to water during heat stress. The increase in rectal temperature was lower (Pbroiler chickens.

  19. Vibration-induced coherence enhances the performance of a biological quantum heat engine

    CERN Document Server

    Chen, Hong-Bin; Chen, Yueh-Nan

    2016-01-01

    Photosynthesis has been the long-standing research interest due to its fundamental importance. Recently, studies on photosynthesis processes also inspire attention from thermodynamical aspect when considering photosynthetic apparatuses as biological quantum heat engines. Quantum coherence is shown to play a crucial role in enhancing the performance of these quantum heat engines. Based on the experimentally reported structure, we propose a quantum heat engine model with a non-Markovian vibrational mode. We show that one can obtain a performance enhancement easily for a wide range of parameters in the presence of the vibrational mode. Our results suggest new insights into the photosynthetic processes and a design principle mimicking natural organisms.

  20. Heat or cold priming-induced cross-tolerance to abiotic stresses in plants: key regulators and possible mechanisms.

    Science.gov (United States)

    Hossain, Mohammad Anwar; Li, Zhong-Guang; Hoque, Tahsina Sharmin; Burritt, David J; Fujita, Masayuki; Munné-Bosch, Sergi

    2018-01-01

    Plants growing under field conditions are constantly exposed, either simultaneously or sequentially, to more than one abiotic stress factor. Plants have evolved sophisticated sensory systems to perceive a number of stress signals that allow them to activate the most adequate response to grow and survive in a given environment. Recently, cross-stress tolerance (i.e. tolerance to a second, strong stress after a different type of mild primary stress) has gained attention as a potential means of producing stress-resistant crops to aid with global food security. Heat or cold priming-induced cross-tolerance is very common in plants and often results from the synergistic co-activation of multiple stress signalling pathways, which involve reactive nitrogen species (RNS), reactive oxygen species (ROS), reactive carbonyl species (RCS), plant hormones and transcription factors. Recent studies have shown that the signalling functions of ROS, RNS and RCS, most particularly hydrogen peroxide, nitric oxide (NO) and methylglyoxal (MG), provide resistance to abiotic stresses and underpin cross-stress tolerance in plants by modulating the expression of genes as well as the post-translational modification of proteins. The current review highlights the key regulators and mechanisms underlying heat or cold priming-induced cross-stress tolerance in plants, with a focus on ROS, MG and NO signalling, as well as on the role of antioxidant and glyoxalase systems, osmolytes, heat-shock proteins (HSPs) and hormones. Our aim is also to provide a comprehensive idea on the topic for researchers using heat or cold priming-induced cross-tolerance as a mechanism to improve crop yields under multiple abiotic stresses.

  1. Secure amplify-and-forward untrusted relaying networks using cooperative jamming and zero-forcing cancelation

    KAUST Repository

    Park, Kihong

    2015-12-03

    In this paper, we investigate secure transmission in untrusted amplify-and-forward half-duplex relaying networks with the help of cooperative jamming at the destination (CJD). Under the assumption of full channel state information (CSI), conventional CJD using self-interference cancelation at the destination is efficient when the untrusted relay has no capability to suppress the jamming signal. However, if the source and destination are equipped with a single antenna and the only untrusted relay is equipped with N multiple antennas, it can remove the jamming signal from the received signal by linear filters and the full multiplexing gain of relaying cannot be achievable with the conventional CJD due to the saturation of the secrecy rate at the high transmit power regime. We propose in this paper new CJD scheme where neither destination nor relay can acquire CSI of relay-destination link. Our proposed scheme utilizes zero-forcing cancelation based on known jamming signals instead of self-interference subtraction, while the untrusted relay cannot suppress the jamming signals due to the lack of CSI. We show that the secrecy rate of the proposed scheme can enjoy a half of multiplexing gain in half-duplex relaying while that of conventional CJD is saturated at high transmit power for N ???2. The impact of channel estimation error at the destination is also investigated to show the robustness of the proposed scheme against strong estimation errors.

  2. Characteristics of physico-chemical properties of bilberry (Vaccinium myrtillus L.) jams with added herbs.

    Science.gov (United States)

    Korus, Anna; Jaworska, Grażyna; Bernaś, Emilia; Juszczak, Lesław

    2015-05-01

    Low-sugar bilberry jams without added herbs and those with added mentha (1 %) and lemon balm (1 %) were examined for levels of selected physico-chemical indicators, antioxidant activity, colour and texture. Jams were obtained by two methods: cooked in an open pan and cooked in a vacuum evaporator. 100 g fresh mass contained 0.076-0.481 mg HMF, 5.8-7.1 mg vitamin C, 176-232 mg total polyphenols, 122-156 mg total flavonoids, 73-96 mg total anthocyanins, with antioxidant activity per 1 g of 405-575 μM Trolox (ABTS), 71-89 μM Trolox (DPPH) and 120-176 μM Fe(2+) (FRAP). Jams cooked in a vacuum evaporator had higher levels of the indicators examined, better colour and worse texture. Jams with added herbs generally showed higher levels of all indicators, but their colour and texture were slightly worse. Storing jams for 8 months caused a reduction in antioxidant constituents of 7-20 % along with a deterioration of colour and texture.

  3. Solar-simulated radiation and heat treatment induced metalloproteinase-1 expression in cultured dermal fibroblasts via distinct pathways: implications on reduction of sun-associated aging.

    Science.gov (United States)

    Lan, Cheng-Che E; Wu, Ching-Shang; Yu, Hsin-Su

    2013-12-01

    Sun exposure is an important environmental factor affecting human beings. Most knowledge regarding solar aging focused on light radiation (photoaging), and little emphasis has been placed on heat, a factor that is also closely associated with sun exposure. This study was launched to evaluate the effects of simulated solar radiation (SSR) and environmental heat on skin fibroblasts in terms of dermal aging. Cultured human dermal fibroblasts were treated with moderate amount of SSR (200J/cm(2)) and heat (+2°C). The metalloproteinase-1 (MMP-1) expression was used as a surrogate marker for dermal aging and the involved regulatory mechanisms were explored. Both treatment conditions did not affect viability but significantly increased the expressions of MMP-1. In parallel, both treatments increased the intracellular levels of reactive oxygen species (ROS), but the increase induced by SSR is much greater than heat. In contrast, transient receptor potential vanilloid 1 (TRPV-1), the sensor of environmental heat, was upregulated by heat but not SSR treatment. Pretreating fibroblasts with antioxidant abrogated the SSR-induced MMP-1 but has limited effect on heat-induced MMP-1. On the other hand, TRPV-1 antagonist pretreatment reduced heat-induced MMP-1 in fibroblasts but not their SSR-treated counterparts. Both SSR and heat induced MMP-1 expression in dermal fibroblasts but through different pathways. As current strategies for reducing sun-related aging focused on filtering of light and use of antioxidants, future strategies design to reduce solar aging should also incorporate heat-induced aging into consideration. Copyright © 2013 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.

  4. Heat and turbulent kinetic energy budgets for surface layer cooling induced by the passage of Hurricane Frances (2004)

    Science.gov (United States)

    Huang, Peisheng; Sanford, Thomas B.; Imberger, JöRg

    2009-12-01

    Heat and turbulent kinetic energy budgets of the ocean surface layer during the passage of Hurricane Frances were examined using a three-dimensional hydrodynamic model. In situ data obtained with the Electromagnetic-Autonomous Profiling Explorer (EM-APEX) floats were used to set up the initial conditions of the model simulation and to compare to the simulation results. The spatial heat budgets reveal that during the hurricane passage, not only the entrainment in the bottom of surface mixed layer but also the horizontal water advection were important factors determining the spatial pattern of sea surface temperature. At the free surface, the hurricane-brought precipitation contributed a negligible amount to the air-sea heat exchange, but the precipitation produced a negative buoyancy flux in the surface layer that overwhelmed the instability induced by the heat loss to the atmosphere. Integrated over the domain within 400 km of the hurricane eye on day 245.71 of 2004, the rate of heat anomaly in the surface water was estimated to be about 0.45 PW (1 PW = 1015 W), with about 20% (0.09 PW in total) of this was due to the heat exchange at the air-sea interface, and almost all the remainder (0.36 PW) was downward transported by oceanic vertical mixing. Shear production was the major source of turbulent kinetic energy amounting 88.5% of the source of turbulent kinetic energy, while the rest (11.5%) was attributed to the wind stirring at sea surface. The increase of ocean potential energy due to vertical mixing represented 7.3% of the energy deposited by wind stress.

  5. Dynamical heating of the polar summer mesopause induced by solar proton events

    Science.gov (United States)

    Becker, Erich; von Savigny, Christian

    A solar proton event (SPE) causes enhanced ionization of water vapor and nitrogen in the lower mesosphere, leading to production of odd hydrogen and odd nitrogen and hence a temporary depletion of ozone. Therefore, the main direct effect on the large circulation in the summer mesosophere/lower thermosphere (MLT) is a diabatic cooling perturbation centered around the pole in the lower mesosphere. Satellite observations made with the MLS/Aura showed a maximum increase of ¿ 10 K in zonally averaged temperatures around the southern polar summer mesopause during the SPE in January 2005 (v. Savigny et al., 2007, GRL). We propose a mechanism that explains this warming as a dynamical consequence of the cooling below (Becker and v. Savigny, 2009, JGR). We employ the Kuehlungsborn Mechanistic general Circulation Model (KMCM), which is a spectral model with high spatial resolution and a sophisticated parameterization of turbulence, giving rise to explicit simulation of gravity-wave effects in the MLT (Becker, 2009, JAS). An SPE is mimicked in the following way: We start with a control simulation for permanent Jan-uary conditions, extract an arbitrary snapshot, and integrate the model with an additional lower mesospheric cooling. This cooling is switched off after 5 days and the model is integrated for another 10 days. The resulting 15 day time series constitutes an SPE-related perturbation simulation when compared to the corresponding 15-day time series of the control simulation. To improve the statistics, the procedure is repeated six times and composite time series are con-structed. The model response in the SPE case reproduces the warming around the mesopause, which can be explained as follows. The diabatic cooling in the lower summer mesosphere induces an anomalous eastward zonal wind component. As a result, eastward propagating gravity waves are Doppler-shifted to smaller intrinsic frequencies and hence are subject to turbulent damping at lower altitudes. Hence, the

  6. Stochastic modeling of stock price process induced from the conjugate heat equation

    Science.gov (United States)

    Paeng, Seong-Hun

    2015-02-01

    Currency can be considered as a ruler for values of commodities. Then the price is the measured value by the ruler. We can suppose that inflation and variation of exchange rate are caused by variation of the scale of the ruler. In geometry, variation of the scale means that the metric is time-dependent. The conjugate heat equation is the modified heat equation which satisfies the heat conservation law for the time-dependent metric space. We propose a new model of stock prices by using the stochastic process whose transition probability is determined by the kernel of the conjugate heat equation. Our model of stock prices shows how the volatility term is affected by inflation and exchange rate. This model modifies the Black-Scholes equation in light of inflation and exchange rate.

  7. Reduced carbohydrate availability does not modulate training-induced heat shock protein adaptations but does upregulate oxidative enzyme activity in human skeletal muscle

    National Research Council Canada - National Science Library

    James P. Morton; Louise Croft; Jonathan D. Bartlett; Don P. M. MacLaren; Thomas Reilly; Louise Evans; Anne McArdle; Barry Drust

    2009-01-01

    ... for training-induced heat shock protein (HSP) adaptations of skeletal muscle. A secondary aim was to investigate the influence of reduced carbohydrate availability on oxidative adaptations and exercise performance...

  8. Heat-induced alterations in cashew allergen solubility and IgE binding

    Directory of Open Access Journals (Sweden)

    Christopher P. Mattison

    2016-01-01

    Full Text Available Cashew nuts are an increasingly common cause of food allergy. We compare the soluble protein profile of cashew nuts following heating. SDS-PAGE indicate that heating can alter the solubility of cashew nut proteins. The 11S legumin, Ana o 2, dominates the soluble protein content in ready to eat and mildly heated cashew nuts. However, we found that in dark-roasted cashew nuts, the soluble protein profile shifts and the 2S albumin Ana o 3 composes up to 40% of the soluble protein. Analysis of trypsin-treated extracts by LC/MS/MS indicate changes in the relative number and intensity of peptides. The relative cumulative intensity of the 5 most commonly observed Ana o 1 and 2 peptides are altered by heating, while those of the 5 most commonly observed Ana o 3 peptides remaine relatively constant. ELISA experiments indicate that there is a decrease in rabbit IgG and human serum IgE binding to soluble cashew proteins following heating. Our findings indicate that heating can alter the solubility of cashew allergens, resulting in altered IgE binding. Our results support the use of both Ana o 2 and Ana o 3 as potential cashew allergen diagnostic targets.

  9. Heat stress induces expression of HSP genes in genetically divergent chickens.

    Science.gov (United States)

    Cedraz, Haniel; Gromboni, Juliana Gracielle Gonzaga; Garcia, Antonio Amandio Pinto; Farias Filho, Ronaldo Vasconcelos; Souza, Teillor Machado; Oliveira, Eduardo Ribeiro de; Oliveira, Elizangela Bonfim de; Nascimento, Carlos Souza do; Meneghetti, Camila; Wenceslau, Amauri Arias

    2017-01-01

    Chickens are animals that are sensitive to thermal stress, which may decrease their production level in terms that it affects feed intake and thus, decreasing body weight gain. The Heat Shock Factors (HSF) and Heat Shock Proteins (HSP) genes are involved in the key cellular defense mechanisms during exposure in hot environments. Aimed with this study to analyze the expression of HSF1, HSF3, HSP70 and HSP90 genes in two local breeds (Peloco and Caneluda) and a commercial broiler line (Cobb 500®) to verify differences in resistance of these chicken to Heat stress treatment. Chicken were submitted to heat stress under an average temperature of 39°C ± 1. Under stress environment, the HSP70 and HSP90 genes were more expressed in backyard chickens than in broiler. There was a difference in HSP70 and HSP90 expression between Caneluda and Cobb and between Peloco and Cobb under stress and comfort environment respectively. HSP70 expression is higher in local breeds during heat stress than in a commercial broiler line. No significant differences were observed in the expression of HSF1 and HSF3 genes between breeds or environments. HSP70 and HSP90 genes are highly expressed, HSF1 and HSF3 genes did not have high expression in all genetic groups. HSP70 and HSP90 are highly expressed in Peloco and Caneluda within heat stress, these breeds proved to be very resistant to high temperature.

  10. Self-heating of dried industrial tannery wastewater sludge induced by pyrophoric iron sulfides formation.

    Science.gov (United States)

    Bertani, R; Biasin, A; Canu, P; Della Zassa, M; Refosco, D; Simionato, F; Zerlottin, M

    2016-03-15

    Similarly to many powders of solids, dried sludge originated from tannery wastewater may result in a self-heating process, under given circumstances. In most cases, it causes a moderate heating (reaching 70-90°C), but larger, off-design residence times in the drier, in a suboxic atmosphere, extremely reactive solids can be produced. Tannery waste contains several chemicals that mostly end up in the wastewater treatment sludge. Unexpected and uncontrolled self heating could lead to a combustion and even to environmental problems. Elaborating on previous studies, with the addition of several analytical determinations, before and after the self-heating, we attempted to formulate a mechanism for the onset of heating. We demonstrated that the system Fe/S/O has been involved in the process. We proved that the formation of small quantities of pyrophoric iron sulfides is the key. They are converted to sulfated by reaction with water and oxygen with exothermic processes. The pyrite/pyrrhotite production depends on the sludge drying process. The oxidation of sulfides to oxides and sulfates through exothermic steps, reasonably catalyzed by metals in the sludge, occurs preferentially in a moist environment. The mechanism has been proved by reproducing in the laboratory prolonged heating under anoxic/suboxic atmosphere. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. MRI temperature map reconstruction directly from k-space with compensation for heating-induced geometric distortions

    Science.gov (United States)

    Gaur, Pooja; Grissom, William A.

    2017-03-01

    Proton resonance frequency (PRF) change is used to measure tissue heating, but also distorts the image and causes geometric distortions in temperature estimates in the same manner as other chemical shift distortions if left uncompensated. We propose an algorithm that produces PRF temperature maps free of these distortions by fitting a signal model directly to acquired k-space data that accounts for PRF-induced phase both up to and during the readout. We also introduce a faster method compatible with Cartesian data that corrects distortions from image-domain temperature maps. Gel heating experiments show the proposed CS compensation algorithms correct magnitude image artifacts and hotspot distortions. Without CS compensation, thermal dose values are overestimated in spiral data, and are spatially offset in 2DFT and EPI data. Compensating for heat-induced CS distortions improves the accuracy of temperature change and thermal dose measurements, and can have a significant positive impact on clinical and research applications of PRF-shift thermometry.

  12. Heat shock-induced accumulation of translation elongation and termination factors precedes assembly of stress granules in S. cerevisiae.

    Directory of Open Access Journals (Sweden)

    Tomas Grousl

    Full Text Available In response to severe environmental stresses eukaryotic cells shut down translation and accumulate components of the translational machinery in stress granules (SGs. Since they contain mainly mRNA, translation initiation factors and 40S ribosomal subunits, they have been referred to as dominant accumulations of stalled translation preinitiation complexes. Here we present evidence that the robust heat shock-induced SGs of S. cerevisiae also contain translation elongation factors eEF3 (Yef3p and eEF1Bγ2 (Tef4p as well as translation termination factors eRF1 (Sup45p and eRF3 (Sup35p. Despite the presence of the yeast prion protein Sup35 in heat shock-induced SGs, we found out that its prion-like domain is not involved in the SGs assembly. Factors eEF3, eEF1Bγ2 and eRF1 were accumulated and co-localized with Dcp2 foci even upon a milder heat shock at 42°C independently of P-bodies scaffolding proteins. We also show that eEF3 accumulations at 42°C determine sites of the genuine SGs assembly at 46°C. We suggest that identification of translation elongation and termination factors in SGs might help to understand the mechanism of the eIF2α factor phosphorylation-independent repression of translation and SGs assembly.

  13. Potential Remedies for the High Synchrotron-Radiation-Induced Heat Load for Future Highest-Energy-Proton Circular Colliders

    CERN Document Server

    AUTHOR|(CDS)2084568; Baglin, Vincent; Schaefers, Franz

    2015-01-01

    We propose a new method for handling the high synchrotron radiation (SR) induced heat load of future circular hadron colliders (like FCC-hh). FCC-hh are dominated by the production of SR, which causes a significant heat load on the accelerator walls. Removal of such a heat load in the cold part of the machine, as done in the Large Hadron Collider, will require more than 100 MW of electrical power and a major cooling system. We studied a totally different approach, identifying an accelerator beam screen whose illuminated surface is able to forward reflect most of the photons impinging onto it. Such a reflecting beam screen will transport a significant part of this heat load outside the cold dipoles. Then, in room temperature sections, it could be more efficiently dissipated. Here we will analyze the proposed solution and address its full compatibility with all other aspects an accelerator beam screen must fulfill to keep under control beam instabilities as caused by electron cloud formation, impedance, dynamic...

  14. First report of charge-transfer induced heat-set hydrogel. Structural insights and remarkable properties

    Science.gov (United States)

    Bhattacharjee, Subham; Maiti, Bappa; Bhattacharya, Santanu

    2016-05-01

    The remarkable ability of a charge-transfer (CT) complex prepared from a pyrene-based donor (Py-D) and a naphthalenediimide-based acceptor (NDI-A) led to the formation of a deep-violet in color, transparent hydrogel at room temperature (RT-gel). Simultaneously, the RT-gel was diluted beyond its critical gelator concentration (CGC) to obtain a transparent sol. Very interestingly, the resultant sol, on heating above 70 °C, transformed into a heat-set gel instantaneously with a hitherto unknown CGC value. Detailed studies revealed the smaller globular aggregates of the RT-gels fuse to form giant globules upon heating, which, in turn, resulted in heat-set gelation through further aggregation. The thermoresponsive property of Py-D alone and 1 : 1 Py-D : NDI-A CT complex was investigated in detail which revealed the hydrophobic collapse of the oxyethylene chains of the CT complex upon heating was mainly responsible for heat-set gelation. Thixotropy, injectability, as well as stimuli responsiveness of the RT-gels were also addressed. In contrast, heat-set gel did not show thixotropic behavior. The X-ray diffraction (XRD) patterns of the xerogel depicted lamellar packing of the CT stacks in the gel phase. Single crystal XRD studies further evidenced the 1 : 1 mixed CT stack formation in the lamellae and also ruled out orthogonal hydrogen bonding possibilities among the hydrazide unit in the CT gel although such interaction was observed in a single crystal of NDI-A alone. In addition, a Ag+-ion triggered metallogelation of NDI-A and nematic liquid-crystalline property of Py-D were also observed.The remarkable ability of a charge-transfer (CT) complex prepared from a pyrene-based donor (Py-D) and a naphthalenediimide-based acceptor (NDI-A) led to the formation of a deep-violet in color, transparent hydrogel at room temperature (RT-gel). Simultaneously, the RT-gel was diluted beyond its critical gelator concentration (CGC) to obtain a transparent sol. Very interestingly, the

  15. The junctional adhesion molecule JAM-C regulates polarized transendothelial migration of neutrophils in vivo.

    Science.gov (United States)

    Woodfin, Abigail; Voisin, Mathieu-Benoit; Beyrau, Martina; Colom, Bartomeu; Caille, Dorothée; Diapouli, Frantzeska-Maria; Nash, Gerard B; Chavakis, Triantafyllos; Albelda, Steven M; Rainger, G Ed; Meda, Paolo; Imhof, Beat A; Nourshargh, Sussan

    2011-06-26

    The migration of neutrophils into inflamed tissues is a fundamental component of innate immunity. A decisive step in this process is the polarized migration of blood neutrophils through endothelial cells (ECs) lining the venular lumen (transendothelial migration (TEM)) in a luminal-to-abluminal direction. By real-time confocal imaging, we found that neutrophils had disrupted polarized TEM ('hesitant' and 'reverse') in vivo. We noted these events in inflammation after ischemia-reperfusion injury, characterized by lower expression of junctional adhesion molecule C (JAM-C) at EC junctions, and they were enhanced by blockade or genetic deletion of JAM-C in ECs. Our results identify JAM-C as a key regulator of polarized neutrophil TEM in vivo and suggest that reverse TEM of neutrophils can contribute to the dissemination of systemic inflammation.

  16. Modeling the capability of penetrating a jammed crowd to eliminate freezing transition

    Science.gov (United States)

    Mohammed Mahmod, Shuaib

    2016-05-01

    Frozen state from jammed state is one of the most interesting aspects produced when simulating the multidirectional pedestrian flow of high density crowds. Cases of real life situations for such a phenomenon are not exhaustively treated. Our observations in the Hajj crowd show that freezing transition does not occur very often. On the contrary, penetrating a jammed crowd is a common aspect. We believe the kindness of pedestrians facing others whose walking is blocked is a main factor in eliminating the frozen state as well as in relieving the jammed state. We refine the social force model by incorporating a new social force to enable the simulated pedestrians to mimic the real behavior observed in the Hajj area. Simulations are performed to validate the work qualitatively.

  17. Silica Polypeptide Composite Particles as Responsive Materials for Jamming Transition Studies

    Science.gov (United States)

    Blake, Alyssa; Russo, Paul

    Silica polypeptide composite particles consisting of an inorganic, colloidal silica core and an organic polypeptide shell can be used as model systems for studying biological and physical particle interactions. The polypeptide shell can undergo secondary conformational transitions between an alpha helix and random coil conformation, which results in a stimuli responsive material. Jamming of responsive materials has mainly used stimuli responsive polymers such as PNIPAM but these particles can undergo similar changes by switching the polypeptide conformation. Preliminary jamming studies of the polypeptide composite particles, using fluorescence photobleaching recovery, can be conducted to determine how responsive polymers effect the jamming phase transition of soft colloidal materials. National Science Foundation under Grant No 1505105 (DMR).

  18. Cooperative jamming power control to enhance secrecy communications of AF Relaying systems for Rayleigh fading channel

    KAUST Repository

    Park, Kihong

    2012-09-01

    In this paper, we investigate secrecy communications in two-hop wireless relaying networks which consist of one source, one amplify-and-forward (AF) relay, one legitimate destination, and one eavesdropper. To prevent the eavesdropper from intercepting the source message, we make the destination send the intended noise to the AF relay during the first phase. This is referred to as cooperative jamming. According to the channel information at the destination, we address two types of jamming power allocation; (i) rate-optimal power allocation and (ii) outage-optimal power allocation. More specifically, without the instantaneous channel knowledge for the eavesdropper side, the outage probability of the secrecy rate is minimized with respect to the intended noise power level. We show that the outage-optimal allocation gives almost the same outage probability as the rateoptimal one. In addition, the jamming power consumption can be significantly reduced compared to the fixed and rate-optimal power allocation methods. © 2012 IEEE.

  19. Teologi Humanis Jamâl al-Bannâ: Sebuah Rekonstruksi Epistemologis Studi Keislaman

    Directory of Open Access Journals (Sweden)

    Mukhammad Zamzami

    2015-10-01

    Full Text Available This article mainly discusses Jamâl al-Bannâ’s thought, an Egyptian-born Muslim contemporary thinker, who offers the idea of humanist theology. As Jamâl observed that the Islamic theology ignores the aspect of humanity, he then tried to fix it with an attempt to, firstly, reconstruct the sources and system of Islamic thought into three things, namely the Qur’ân, the Sunnah, and the Hikmah (Wisdom. Each aspect is read through “new method of reading” aiming that the stream of Islamic theology will flow more humanist and will be able to synergize with its time. Jamâl’s stream of thought is centered on the aspect of humanity emphasizing that every product of Islamic thoughts should have a hook with the principles of justice and welfare, because that is the main principle of Islamic teachings.

  20. Using IR spectroscopy and multivariate curve resolution to elucidate mechanism of heat-induced decomposition of an organic complex

    DEFF Research Database (Denmark)

    Karpushkin, Evgeny; Gvozdik, Nataliya; Kucheryavskiy, Sergey V.

    the opportunity to carry out simultaneous thermogravimetry/differential scanning calorimetry analysis and IR/Raman/mass spectrometry investigation of the evolving gaseous products. However, elucidation of the mechanism of the reactions occurring upon heat- ing is not completely straightforward, due to a number...... and discuss the results of TGA-DSC-IR study of heat-induced decomposition of tris(acetylacetonato)manganese(III) complex. Using this process as an example, we have indicated the complications of the evolved gas analysis and demonstrated that they can be partially overcome taking advantage of multivariate...... the meaningful information from the set of the evolved gas spectra. The elaborated approach is fairly general and applicable for study of a variety of the processes accompanied by evolution of gaseous products....

  1. Formulation of Hydrocolloid-Agar, Sucrose, and Acidulant on Jam Leather Product Development

    Directory of Open Access Journals (Sweden)

    Wahyu Ramadhan

    2017-04-01

    Full Text Available Tallying agar powder as a texturizer in guava single sheet jam instigate the product more convenience to consumed. The aims of this research were to determine the best concentration of sucrose, citric acid and agar powder to form a good quality guava jam slice. The research method are optimization and formulationof sucrose, citric acid and agar-agar on making guava jam single sheets product. Physochemical and sensory tests were performed to reveal the best formulation of guava jam slice and the Bayes method used to determine the optimization of the selected formula. Based on the results of formulation and analysis, itwas obtained that  the guava jam slice with Acidulant concentration (0.02%, 0.04%, 0.06%, sucrose (70%, 80%, 90%, 100% and agar powder (0.7%, 0.8%, 0.9%, 1.0%, 1.1%, 1.2% had pH 3.63-3.90, sugar content 34.68 g/100 g – 35.76 g/100 g, color intensity L*, a*, b* with ΔE* value was 37,88-53,97, fiber content 1.01%-1.59%, and water activity 0.852-0.893. Rheology properties for texture profile (hardness, cohesiveness, springiness, adhesive force, and gumminess also showed significant value with agar powder formulation. Based on the Bayes test and hedonic test, it was found that the best formula was for guava jam slices with the addition of 90% sucrose, citric acid 0.04% and agar powder 0.9%. From the best formula, it was found the shelf life prediction model of Arrhenius formula was ln k = 20.222-6660.6(1/T and the nutrition facts contribute total energy 45 kcal, fat 0%, carbohydrate 9%, protein 2% and dietary fiber 3%.

  2. Thermomechanically-induced convective motion and natural convection in confined gaseous helium subjected to boundary heating

    Science.gov (United States)

    Sutrisno

    A theoretical analysis of the effects of a gravity field on gaseous helium confined in a slender two dimensional box when boundary heating suddenly takes place at the wall is described. The gravity field is applied vertically. A heat flux, capable of producing an appreciable wall temperature increase, is applied uniformly along the longer vertical walls. A systematic analysis using various perturbation techniques is carried out in the central region away from the upper and lower insulated boundaries. A complete system of conservation equations governing viscous, heat conducting and compressible flow is employed. Analysis on the acoustic timescale shows that conduction heating takes place only in a thin, continuously growing boundary layer near the heated wall. On the conduction timescale, both acoustic and conduction phenomena occur simultaneously in the container. Multiple timescale methods are employed to separate the high frequency acoustic equations from the lower frequency conduction equations. In this fully conductive system, energy is transferred by conduction among the fluid particles which at the same time experience thermal expansion and compression.

  3. Heating-induced variations of secondary electron emission from ion-cleaned copper samples.

    Science.gov (United States)

    Hu, Xiao-Chuan; Zhang, Hai-Bo; Cao, Meng; Zhang, Na; Cui, Wan-Zhao

    2014-09-01

    Secondary electron (SE) emission due to electron impact depends strongly on surface conditions. The variations of SE yield and spectrum with the heating temperature of Ar-ion-cleaned oxygen-free copper samples are therefore measured in situ in a multifunctional ultrahigh vacuum system. The SE yield and the SE spectrum are observed to increase and to narrow, respectively, after sample heating. The maximum SE yield increases from 0.97 before heating to 1.25 after heating at ∼313 °C, and the corresponding full width at half maximum of SE spectrum decreases considerably from 9.3 to 5.5 eV. More CO2 and Ar ions are shown to desorb at a higher heating temperature by residual gas analysis, indicating their contribution to the reduction in work function and surface potential barrier. Ar-ion desorption appears to affect the SE spectrum more than the SE yield. The obtained results provide a new insight into complicated surface influences on SE emission in thermal applications of scanning electron microscopy. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Characterization of residual stresses in heat treated Ti-6Al-4V forgings by machining induced distortion

    Directory of Open Access Journals (Sweden)

    Werner E.

    2010-06-01

    Full Text Available To provide a solid base for improved material exploitation in dimensioning calculations it is necessary to determine the stress state in the part prior to service loading. In order to achieve higher material strength at elevated temperatures, the surface temperature gradient with respect to time has to be sufficiently high during heat treatment. This results in non-negligable residual stresses that can reduce the allowable load level upon which yielding occurs. For titanium alloys there are two common heat treatments, namely solution treatment and mill annealing. The latter one is the method of choice within the presented project. Mill annealing is utilized in order to significantly reduce the residual stresses in the parts without loosing much of the improved strength at elevated temperatures. Quantification of residual stresses is done by solving an inverse problem. From the measurement of distortion, induced by dividing the investigated part, the residual stress state can be calculated via analytical modeling or correlation with finite element models. To assure a minimum perturbation of the residual stress state during specimen production, dividing of the part is accomplished by electric discharge machining. The parts of interest are v-shaped prisms with a length of approximatly 450 mm and a thickness in the cross sectional area from about 20 mm to 45 mm. Figure 1(a shows the forged part and 1(b the dimensions of the cross section in millimeters as well as the material properties considered in the finite element model. The heat exchange between the part and the environment is modelled as heat transfer by convection superimposed with heat radiation. Since the parts are exposed to air during forging and heat treatment, the surface develops a strongly adhesive oxide layer, the so called alpha-case. After forging the parts are cooled in air and heat treated at a temperature of 720° C for a duration of 120 min. Subsequent air cooling and

  5. Characterization of residual stresses in heat treated Ti-6Al-4V forgings by machining induced distortion

    Science.gov (United States)

    Regener, B.; Krempaszky, C.; Werner, E.

    2010-06-01

    To provide a solid base for improved material exploitation in dimensioning calculations it is necessary to determine the stress state in the part prior to service loading. In order to achieve higher material strength at elevated temperatures, the surface temperature gradient with respect to time has to be sufficiently high during heat treatment. This results in non-negligable residual stresses that can reduce the allowable load level upon which yielding occurs. For titanium alloys there are two common heat treatments, namely solution treatment and mill annealing. The latter one is the method of choice within the presented project. Mill annealing is utilized in order to significantly reduce the residual stresses in the parts without loosing much of the improved strength at elevated temperatures. Quantification of residual stresses is done by solving an inverse problem. From the measurement of distortion, induced by dividing the investigated part, the residual stress state can be calculated via analytical modeling or correlation with finite element models. To assure a minimum perturbation of the residual stress state during specimen production, dividing of the part is accomplished by electric discharge machining. The parts of interest are v-shaped prisms with a length of approximatly 450 mm and a thickness in the cross sectional area from about 20 mm to 45 mm. Figure 1(a) shows the forged part and 1(b) the dimensions of the cross section in millimeters as well as the material properties considered in the finite element model. The heat exchange between the part and the environment is modelled as heat transfer by convection superimposed with heat radiation. Since the parts are exposed to air during forging and heat treatment, the surface develops a strongly adhesive oxide layer, the so called alpha-case. After forging the parts are cooled in air and heat treated at a temperature of 720° C for a duration of 120 min. Subsequent air cooling and removing the alpha-case by

  6. EFFECTS OF PALM VITAMIN E SUPPLEMENTATION ON EXERCISE-INDUCED OXIDATIVE STRESS AND ENDURANCE PERFORMANCE IN THE HEAT

    Directory of Open Access Journals (Sweden)

    Chen Chee Keong

    2006-12-01

    Full Text Available This study investigates the effects of tocotrienol-rich palm vitamin E supplementation on exercise-induced lipid peroxidation and endurance performance in the heat. In a double blind, cross-over study, eighteen healthy, male recreational athletes completed two endurance running trials, until exhaustion, on a motorized treadmill at 70% VO2max on two separate occasions following a 6-week supplementation regimen of either tocotrienol-rich palm vitamin E (E or placebo (P. Both trials were conducted in the heat (31oC, 70% relative humidity. During the trials, rectal temperature (Trec, ratings of perceived exertion (RPE and oxygen uptake (VO2 were recorded. Blood samples were collected for the determination of plasma volume changes (PVC, malondialdehyde (MDA, creatine kinase (CK, total antioxidant status (TAS and vitamin E. After the supplementation regimen, serum alpha-tocopherol increased ~33% but serum concentrations of tocotrienols were negligible. No significant differences were evident in mean Trec, RPE, VO2 or in the time to exhaustion between the E-supplemented and the placebo- supplemented groups. Similarly, mean PVC, CK and TAS were also not different between the two groups. Resting plasma mean MDA concentration in the E-supplemented group was significantly lower than that in the placebo-supplemented group. At exhaustion, plasma mean MDA was higher than the resting values in both groups. Although tocotrienol-rich palm vitamin E supplementation decreased lipid peroxidation at rest and, to some extent, during exercise in the heat, as evident from the lower MDA levels, it however did not enhance endurance running performance or prevent exercise-induced muscle damage or influenced body core temperature or plasma volume changes during exercise in the heat

  7. On the estimation of the worst-case implant-induced RF-heating in multi-channel MRI

    Science.gov (United States)

    Córcoles, Juan; Zastrow, Earl; Kuster, Niels

    2017-06-01

    The increasing use of multiple radiofrequency (RF) transmit channels in magnetic resonance imaging (MRI) systems makes it necessary to rigorously assess the risk of RF-induced heating. This risk is especially aggravated with inclusions of medical implants within the body. The worst-case RF-heating scenario is achieved when the local tissue deposition in the at-risk region (generally in the vicinity of the implant electrodes) reaches its maximum value while MRI exposure is compliant with predefined general specific absorption rate (SAR) limits or power requirements. This work first reviews the common approach to estimate the worst-case RF-induced heating in multi-channel MRI environment, based on the maximization of the ratio of two Hermitian forms by solving a generalized eigenvalue problem. It is then shown that the common approach is not rigorous and may lead to an underestimation of the worst-case RF-heating scenario when there is a large number of RF transmit channels and there exist multiple SAR or power constraints to be satisfied. Finally, this work derives a rigorous SAR-based formulation to estimate a preferable worst-case scenario, which is solved by casting a semidefinite programming relaxation of this original non-convex problem, whose solution closely approximates the true worst-case including all SAR constraints. Numerical results for 2, 4, 8, 16, and 32 RF channels in a 3T-MRI volume coil for a patient with a deep-brain stimulator under a head imaging exposure are provided as illustrative examples.

  8. Effect of Geranylgeranylacetone on Ultraviolet Radiation Type B-Induced Cataract in Heat-Shock Transcription Factor 1 Heterozygous Mouse.

    Science.gov (United States)

    Ogasawara, Satoshi; Hashizume, Kouhei; Okuno, Takashi; Imaizumi, Toshiyasu; Inomata, Yui; Tezuka, Yu; Sanbe, Atushi; Kurosaka, Daijiro

    2017-05-01

    We investigated whether heat-shock transcription factor 1 (HSF1) was involved in ultraviolet radiation type B (UVR-B)-induced lens opacity (cataract) using HSF1 heterozygous mice. We also examined the effects of geranylgeranylacetone (GGA), an inducer of heat-shock proteins via activation of HSF, on the UVR-B-induced cataract. Male HSF1+/- and WT mice were unilaterally exposed to UVR-B (total: 1200mJ) at 16 weeks of age. At 48 h after the last UVR-B irradiation, the lens was isolated and the induction of the cataract was quantified as the cataract area ratio (opacity area/anterior capsule). GGA was orally administered at a dosage of 500 mg/kg once a day for two days before the first UVR-B exposure until the end of the experiment (21days in total). The HSF1 expression was more greatly decreased in the lens from HSF1+/- mice than in that from WT mice (p cataracts in the anterior capsule in both HSF1+/- and WT mice, while the opacity of the lens was markedly enhanced in HSF1+/- mice compared to that in WT mice(p (0.01). GGA treatment could prevent the induction of lens opacity by UVR-B exposure in both WT and HSF1+/- mice as compared with the non-administration group (p cataracts, possibly via regulation of HSPs such as HSP25.

  9. Effect of heat-induced pain stimuli on pulse transit time and pulse wave amplitude in healthy volunteers.

    Science.gov (United States)

    van Velzen, Marit H N; Loeve, Arjo J; Kortekaas, Minke C; Niehof, Sjoerd P; Mik, Egbert G; Stolker, Robert J

    2016-01-01

    Pain is commonly assessed subjectively by interpretations of patient behaviour and/or reports from patients. When this is impossible the availability of a quantitative objective pain assessment tool based on objective physiological parameters would greatly benefit clinical practice and research beside the standard self-report tests. Vasoconstriction is one of the physiological responses to pain. The aim of this study was to investigate whether pulse transit time (PTT) and pulse wave amplitude (PWA) decrease in response to this vasoconstriction when caused by heat-induced pain. The PTT and PWA were measured in healthy volunteers, on both index fingers using photoplethysmography and electrocardiography. Each subject received 3 heat-induced pain stimuli using a Temperature-Sensory Analyzer thermode block to apply a controlled, increasing temperature from 32.0 °C to 50.0 °C to the skin. After reaching 50.0 °C, the thermode was immediately cooled down to 32.0 °C. The study population was divided into 2 groups with a time-interval between the stimuli 20s or 60s. The results showed a significant (p  induced pain causes a decrease of PTT and PWA. Consequently, it is expected that, in the future, PTT and PWA may be applied as objective indicators of pain, either beside the standard self-report test, or when self-report testing is impossible.

  10. Expression of JAM-A, AF-6, PAR-3 and PAR-6 during the assembly and remodeling of RPE tight junctions.

    Science.gov (United States)

    Luo, Yan; Fukuhara, Masayuki; Weitzman, Matthew; Rizzolo, Lawrence J

    2006-09-19

    The tight junctions of the endothelial and epithelial regions of the blood-brain barrier are regulated by interactions with the neighboring tissue. We examined how the neural retina regulates the assembly of tight junctions in the retinal pigment epithelium (RPE). The proteins JAM-A, AF-6, PAR-3 and PAR-6 have been implicated in the assembly of other epithelial tight junctions. Using chick embryos and primary cell culture, we examined gene expression of these proteins during embryonic development, and whether retinal secretions regulate their expression. Three highly conserved RNA splice sites of AF-6 were identified in chick ocular tissues, but only two were expressed in RPE. JAM-A and AF-6 were expressed at relatively high levels early in development when adherens junctions form, but before tight junctions form. Expression of JAM-A and the AF-6 isoforms actually decreased when tight junctions were forming and expanding. The expression of PAR-3 and PAR-6 was constant. Despite the expression of these proteins in vitro (along with claudins, occludin, ZO-1 and ZO-2), the tight junctional networks that form were discontinuous (Rahner, C., Fukuhara, M., Peng, S., Kojima, S., Rizzolo, L.J., 2004. The apical and basal environments of the retinal pigment epithelium regulate the maturation of tight junctions during development. J. Cell Sci. 117, 3307-3318). The expression of these assembly proteins was unaffected by a retinal conditioned medium that induced the completion of tight junction formation. These data indicate that the early expression of the assembly proteins corresponds to the initial establishment of the adherens and tight junctions, but secretory products of the neural retina must induce the expression of additional proteins to complete the maturation process.

  11. MU`JAM `ARABĪ DAN URGENSINYA DALAM PEMBELAJARAN BAHASA ARAB DI PERGURUAN TINGGI AGAMA ISLAM

    Directory of Open Access Journals (Sweden)

    Suhaimi Suhaimi

    2011-08-01

    Full Text Available Among the latest problems encountered in the Arabic teaching in Islamic University is the poor ability of students in comprehending Arabic texts, either classic or contemporary ones. This is not only caused by the insufficiency of student ability in understanding sentence structure, but also the scantiness vocabulary mastery. The use of mu’jam ‘arabi as one of the language learning methods is very important. Unfortunately in Islamic university, there is no exclusive Arabic encyclopedia. This paper explores the urgency of mu’jam in coping with some problems of Arabic teaching in Islamic university, such as IAIN, STAIN and others.

  12. Communication and Jamming BDA of OFDMA Communication Systems Using the Software Defined Radio Platform WARP

    Science.gov (United States)

    2015-03-01

    declared a work of the U.S. Government and is not subject to copyright protection in the United States. AFIT-ENG-MS-15-M-073 COMMUNICATION AND JAMMING...developed with 64 sub carriers and have guards and pilots as comparable to the 802.11a WiFi standard. An eavesdropper/interferer (ExJx) is used to...WARP boards. I also wish to acknowledge FLTLT Nicholas Rutherford for his work on Blind demodulation of pass band OFDMA signals and Jamming Battle

  13. Problematika jamčevalnih zahtevkov potrošnikov z vidika "afere Volkswagen"

    OpenAIRE

    Peče, Žan

    2017-01-01

    V diplomski nalogi je obravnavana problematika jamčevalnih zahtevkov potrošnikov z vidika afere Volkswagen (Dieselgate), v kateri je bilo odkrito, da so v koncernu Volkswagen v svoja vozila nameščali skrito programsko opremo, ki je prirejala podatke o vrednosti izpušnih plinov v času testiranja vozil. V diplomski nalogi so predstavljeni jamčevalni zahtevki, katere imajo zaradi ugotovljene napake na vozilu na voljo potrošniki. Predstavljene so predpostavke, ki morajo biti izpolnjene, da ...

  14. Design Guidelines for Ferrite Absorbers Submitted to RF-induced Heating

    CERN Document Server

    Bertarelli, A

    2013-01-01

    The use of ferrite absorbers is one of the most effective means of damping potentially harmful high order RF modes, which may lead to beam instabilities and excessive power losses in accelerator devices. However, the power deposited on ferrite absorbers themselves maylead to ferrite exceeding its Curie temperature, losing its damping properties. An evaluation of the ferrite capability to dissipate deposited heat is hence of paramount importance for the safe design of particle accelerator devices. In this paper, figures of merit are proposed to assess the maximum specific power allowed on a generic ferrite tile, before it reaches its Curie temperature. Due to its inherent brittleness, sufficient contact pressure between ferrite and its housing, allowing heat transmission by conduction, can hardly be applied. A semi-analytical study is thus performed, assuming that ferrite is evacuating heat solely through radiation. The described method is then exemplified in the case of the BPM-embedded tertiary collimator (T...

  15. Heat stress-induced disruption of endothelial barrier function is via PAR1 signaling and suppressed by Xuebijing injection.

    Directory of Open Access Journals (Sweden)

    Qiulin Xu

    Full Text Available Increased vascular permeability leading to acute lung injury (ALI and acute respiratory distress syndrome (ARDS is central to the pathogenesis of heatstroke. Protease-activated receptor 1 (PAR1, the receptor for thrombin, plays a key role in disruption of endothelial barrier function in response to extracellular stimuli. However, the role of PAR1 in heat stress-induced endothelial hyper-permeability is unknown. In this study, we measured PAR1 protein expression in heat-stressed human umbilical venous endothelial cells (HUVECs, investigated the influences of PAR1 on endothelial permeability, F-actin rearrangement, and moesin phosphorylation by inhibiting PAR1 with its siRNA, neutralizing antibody (anti-PAR1, specific inhibitor(RWJ56110, and Xuebijing injection (XBJ, a traditional Chinese medicine used for sepsis treatment, and evaluated the role of PAR1 in heatstroke-related ALI/ARDS in mice by suppressing PAR1 with RWJ56110, anti-PAR1and XBJ. We found that heat stress induced PAR1 protein expression 2h after heat stress in endothelial cells, caused the release of endothelial matrix metalloprotease 1, an activator of PAR1, after 60 or 120 min of heat stimulation, as well as promoted endothelial hyper-permeability and F-actin rearrangement, which were inhibited by suppressing PAR1 with RWJ56110, anti-PAR1 and siRNA. PAR1 mediated moesin phosphorylation, which caused F-actin rearrangement and disruption of endothelial barrier function. To corroborate findings from in vitro experiments, we found that RWJ56110 and the anti-PAR1 significantly decreased lung edema, pulmonary microvascular permeability, protein exudation, and leukocytes infiltrations in heatstroke mice. Additionally, XBJ was found to suppress PAR1-moesin signal pathway and confer protective effects on maintaining endothelial barrier function both in vitro and in vivo heat-stressed model, similar to those observed above with the inhibition of PAR1. These results suggest that PAR1 is a

  16. Heat-induced structural changes affect OVA-antigen processing and reduce allergic response in mouse model of food allergy.

    Directory of Open Access Journals (Sweden)

    Jaroslav Golias

    Full Text Available BACKGROUND AND AIMS: The egg protein ovalbumin (OVA belongs to six most frequent food allergens. We investigated how thermal processing influences its ability to induce allergic symptoms and immune responses in mouse model of food allergy. METHODOLOGY/PRINCIPAL FINDINGS: Effect of increased temperature (70°C and 95°C on OVA secondary structure was characterized by circular dichroism and by the kinetics of pepsin digestion with subsequent HPLC. BALB/c mice were sensitized intraperitoneally and challenged with repeated gavages of OVA or OVA heated to 70°C (h-OVA. Levels of allergen-specific serum antibodies were determined by ELISA (IgA and IgGs or by β-hexosaminidase release test (IgE. Specific activities of digestive enzymes were determined in brush border membrane vesicles of jejunal enterocytes. Cytokine production and changes in regulatory T cells in mesenteric lymph nodes and spleen were assessed by ELISA and FACS. Heating of OVA to 70°C caused mild irreversible changes in secondary structure compared to boiling to 95°C (b-OVA, but both OVA treatments led to markedly different digestion kinetics and Tregs induction ability in vitro, compared to native OVA. Heating of OVA significantly decreased clinical symptoms (allergic diarrhea and immune allergic response on the level of IgE, IL-4, IL-5, IL-13. Furthermore, h-OVA induced lower activities of serum mast cell protease-1 and enterocyte brush border membrane alkaline phosphatase as compared to native OVA. On the other hand h-OVA stimulated higher IgG2a in sera and IFN-γ secretion by splenocytes. CONCLUSIONS: Minor irreversible changes in OVA secondary structure caused by thermal processing changes both its digestion and antigenic epitopes formation, which leads to activation of different T cell subpopulations, induces shift towards Th1 response and ultimately reduces its allergenicity.

  17. Beam-induced heat loads on the beam screens of the inner triplets for the HL-LHC

    CERN Document Server

    Skripka, Galina; CERN. Geneva. ATS Department

    2018-01-01

    The expected heat load induced on the beam screens has been evaluated for the triplet assemblies in the four experimental Insertion Regions (IRs) of the HL-LHC. The contribution from electron cloud effects has been estimated using PyECLOUD macroparticle simulations. The presence of a surface treatment for the reduction of the Secondary Electron Yield has been taken into account. The contribution from the impedance of the beam screen has been evaluated taking into account the impact of the temperature and of the magnetic field on the resistivity of the surface.

  18. Heat shock preconditioning protects against ER stress-induced apoptosis through the regulation of the BH3-only protein BIM

    Directory of Open Access Journals (Sweden)

    Donna Kennedy

    2014-01-01

    Full Text Available A mild heat shock (HS preconditioning and acquisition of thermotolerance protects cells against a variety of cytotoxic agents that otherwise induce apoptosis. Here we tested whether there is a molecular link between HS preconditioning and endoplasmic reticulum (ER stress-induced apoptosis. ER stress results from a loss of ER lumen homeostasis, culminating in an accumulation of unfolded/misfolded proteins in the ER and activation of unfolded protein response (UPR. Unresolved, ER stress leads to activation of BH3-only proteins, mitochondrial membrane permeabilization, caspase activation and apoptotic cell death. HS preconditioning (1 h at 42 °C induced a rapid increase in HSPA1 (HSP70 levels which remained elevated for at least 48 h post-HS. HS preconditioning significantly reduced BAX, caspase activation and apoptosis in cell cultures treated with the ER stress-inducing agents thapsigargin (TG and tunicamycin (TM. HS-mediated protection was found to be due to regulation of the BH3-only protein BIM. Further, overexpression of HSPA1 could not mimic the effect of HS on BIM expression, suggesting that other HS factors may play a role in inhibiting ER stress-induced apoptosis by regulating BIM.

  19. The effect of inhibition of heat-shock proteins on thiram-induced tibial dyschondroplasia

    National Research Council Canada - National Science Library

    Genin, O; Hasdai, A; Shinder, D; Pines, M

    2012-01-01

    .... Thiram-induced TD is characterized by enlarged, unvascularized growth plates, low levels of the vascular endothelial growth factor receptor Flk-1, abnormal chondrocyte differentiation, and lameness...

  20. Hyperthermia with rotating magnetic nanowires inducing heat into tumor by fluid friction

    Energy Technology Data Exchange (ETDEWEB)

    Egolf, Peter W.; Pawlowski, Anne-Gabrielle; Tsague, Paulin; Marco, Bastien de; Bovy, William; Tucev, Sinisa [Institute of Thermal Sciences and Engineering, University of Applied Sciences of Western Switzerland, CH 1401 Yverdon-les-Bains (Switzerland); Shamsudhin, Naveen, E-mail: snaveen@ethz.ch; Pané, Salvador; Pokki, Juho; Ansari, M. H. D.; Nelson, Bradley J. [Multi-Scale Robotics Lab, Institute of Robotics and Intelligent Systems, ETH Zurich, CH 8092 Zurich (Switzerland); Vuarnoz, Didier [Ecole Polytechnique Fédérale de Lausanne (EPFL), EPFL Fribourg, CH 1701 Fribourg (Switzerland)

    2016-08-14

    A magnetic hyperthermia cancer treatment strategy that does not operate by means of conventional heating mechanisms is presented. The proposed approach consists of injecting a gel with homogeneously distributed magnetic nanowires into a tumor. Upon the application of a low-frequency rotating or circularly polarized magnetic field, nanowires spin around their center of viscous drag due to torque generated by shape anisotropy. As a result of external rotational forcing and fluid friction in the nanoparticle's boundary layer, heating occurs. The nanowire dynamics is theoretically and experimentally investigated, and different feasibility proofs of the principle by physical modeling, which adhere to medical guidelines, are presented. The magnetic nanorotors exhibit rotations and oscillations with quite a steady center of gravity, which proves an immobile behavior and guarantees a time-independent homogeneity of the spatial particle distribution in the tumor. Furthermore, a fluid dynamic and thermodynamic heating model is briefly introduced. This model is a generalization of Penne's model that for this method reveals theoretic heating rates that are sufficiently high, and fits well into medical limits defined by present standards.

  1. Hyperthermia with rotating magnetic nanowires inducing heat into tumor by fluid friction

    Science.gov (United States)

    Egolf, Peter W.; Shamsudhin, Naveen; Pané, Salvador; Vuarnoz, Didier; Pokki, Juho; Pawlowski, Anne-Gabrielle; Tsague, Paulin; de Marco, Bastien; Bovy, William; Tucev, Sinisa; Ansari, M. H. D.; Nelson, Bradley J.

    2016-08-01

    A magnetic hyperthermia cancer treatment strategy that does not operate by means of conventional heating mechanisms is presented. The proposed approach consists of injecting a gel with homogeneously distributed magnetic nanowires into a tumor. Upon the application of a low-frequency rotating or circularly polarized magnetic field, nanowires spin around their center of viscous drag due to torque generated by shape anisotropy. As a result of external rotational forcing and fluid friction in the nanoparticle's boundary layer, heating occurs. The nanowire dynamics is theoretically and experimentally investigated, and different feasibility proofs of the principle by physical modeling, which adhere to medical guidelines, are presented. The magnetic nanorotors exhibit rotations and oscillations with quite a steady center of gravity, which proves an immobile behavior and guarantees a time-independent homogeneity of the spatial particle distribution in the tumor. Furthermore, a fluid dynamic and thermodynamic heating model is briefly introduced. This model is a generalization of Penne's model that for this method reveals theoretic heating rates that are sufficiently high, and fits well into medical limits defined by present standards.

  2. Heat-induced oxidative injury contributes to inhibition of Botrytis cinerea spore germination and growth

    Science.gov (United States)

    The inhibitory effect of a heat treatment (HT) on Botrytis cinerea, a major postharvest fungal pathogen, and the possible mode of action were investigated. Spore germination and germ tube elongation of B. cinerea were both increasingly and significantly inhibited by a HT (43 degrees C) for 10, 20 o...

  3. MR safety: fast T₁ thermometry of the RF-induced heating of medical devices.

    Science.gov (United States)

    Gensler, D; Fidler, F; Ehses, P; Warmuth, M; Reiter, T; Düring, M; Ritter, O; Ladd, M E; Quick, H H; Jakob, P M; Bauer, W R; Nordbeck, P

    2012-11-01

    Determining the MR compatibility of medical implants and devices is becoming increasingly relevant. In most cases, the heating of conductive implants due to radiefrequency (RF) excitation pulses is measured by fluoroptic temperature sensors in relevant tests for approval. Another common method to determine these heating effects is MR thermometry using the proton resonance frequency. This method gives good results in homogeneous phantoms. However in many cases, technical shortcomings such as susceptibility artifacts prohibit exact proton resonance frequency thermometry near medical implants. Therefore, this work aimed at developing a fast T₁-based method which allows controlled MR-related heating of a medical implant while simultaneously quantifying the spatial and temporal temperature distribution. To this end, an inversion recovery snapshot Fast Low-Angle Shot (FLASH) sequence was modified with additional off-resonant heating pulses. With an accelerated imaging method and a sliding-window technique, every 7.6 s a new temperature map could be generated with a spatial in-plane resolution of 2 mm. The temperature deviation from calculated temperature values to reference fluoroptic probe was found to be smaller than 1 K. Copyright © 2012 Wiley Periodicals, Inc.

  4. Welding of Semiconductor Nanowires by Coupling Laser-Induced Peening and Localized Heating

    Science.gov (United States)

    Rickey, Kelly M.; Nian, Qiong; Zhang, Genqiang; Chen, Liangliang; Suslov, Sergey; Bhat, S. Venkataprasad; Wu, Yue; Cheng, Gary J.; Ruan, Xiulin

    2015-11-01

    We demonstrate that laser peening coupled with sintering of CdTe nanowire films substantially enhances film quality and charge transfer while largely maintaining basic particle morphology. During the laser peening phase, a shockwave is used to compress the film. Laser sintering comprises the second step, where a nanosecond pulse laser beam welds the nanowires. Microstructure, morphology, material content, and electrical conductivities of the films are characterized before and after treatment. The morphology results show that laser peening can decrease porosity and bring nanowires into contact, and pulsed laser heating fuses those contacts. Multiphysics simulations coupling electromagnetic and heat transfer modules demonstrate that during pulsed laser heating, local EM field enhancement is generated specifically around the contact areas between two semiconductor nanowires, indicating localized heating. The characterization results indicate that solely laser peening or sintering can only moderately improve the thin film quality; however, when coupled together as laser peen sintering (LPS), the electrical conductivity enhancement is dramatic. LPS can decrease resistivity up to a factor of ~10,000, resulting in values on the order of ~105 Ω-cm in some cases, which is comparable to CdTe thin films. Our work demonstrates that LPS is an effective processing method to obtain high-quality semiconductor nanocrystal films.

  5. Urbanisation-Induced Land Cover Temperature Dynamics for Sustainable Future Urban Heat Island Mitigation

    Directory of Open Access Journals (Sweden)

    Andrew MacLachlan

    2017-12-01

    Full Text Available Urban land cover is one of the fastest global growing land cover types which permanently alters land surface properties and atmospheric interactions, often initiating an urban heat island effect. Urbanisation comprises a number of land cover changes within metropolitan regions. However, these complexities have been somewhat neglected in temperature analysis studies of the urban heat island effect, whereby over-simplification ignores the heterogeneity of urban surfaces and associated land surface temperature dynamics. Accurate spatial information pertaining to these land cover change—temperature relationships across space is essential for policy integration regarding future sustainable city planning to mitigate urban heat impacts. Through a multi-sensor approach, this research disentangles the complex spatial heterogeneous variations between changes in land cover (Landsat data and land surface temperature (MODIS data, to understand the urban heat island effect dynamics in greater detail for appropriate policy integration. The application area is the rapidly expanding Perth Metropolitan Region (PMR in Western Australia (WA. Results indicate that land cover change from forest to urban is associated with the greatest annual daytime and nighttime temperature change of 0.40 °C and 0.88 °C respectively. Conversely, change from grassland to urban minimises temperature change at 0.16 °C and 0.77 °C for annual daytime and nighttime temperature respectively. These findings are important to consider for proposed developments of the city as such detail is not currently considered in the urban growth plans for the PMR. The novel intra-urban research approach presented can be applied to other global metropolitan regions to facilitate future transition towards sustainable cities, whereby urban heat impacts can be better managed through optimised land use planning, moving cities towards alignment with the 2030 sustainable development goals and the City

  6. White-Light-Induced Collective Heating of Gold Nanocomposite/Bombyx mori Silk Thin Films with Ultrahigh Broadband Absorbance.

    Science.gov (United States)

    Tsao, Shao Hsuan; Wan, Dehui; Lai, Yu-Sheng; Chang, Ho-Ming; Yu, Chen-Chieh; Lin, Keng-Te; Chen, Hsuen-Li

    2015-12-22

    This paper describes a systematic investigation of the phenomenon of white-light-induced heating in silk fibroin films embedded with gold nanoparticles (Au NPs). The Au NPs functioned to develop an ultrahigh broadband absorber, allowing white light to be used as a source for photothermal generation. With an increase of the Au content in the composite films, the absorbance was enhanced significantly around the localized surface plasmon resonance (LSPR) wavelength, while non-LSPR wavelengths were also increased dramatically. The greater amount of absorbed light increased the rate of photoheating. The optimized composite film exhibited ultrahigh absorbances of approximately 95% over the spectral range from 350 to 750 nm, with moderate absorbances (>60%) at longer wavelengths (750-1000 nm). As a result, the composite film absorbed almost all of the incident light and, accordingly, converted this optical energy to local heat. Therefore, significant temperature increases (ca. 100 °C) were readily obtained when we irradiated the composite film under a light-emitting diode or halogen lamp. Moreover, such composite films displayed linear light-to-heat responses with respect to the light intensity, as well as great photothermal stability. A broadband absorptive film coated on a simple Al/Si Schottky diode displayed a linear, significant, stable photo-thermo-electronic effect in response to varying the light intensity.

  7. Urbanization-induced urban heat island and aerosol effects on climate extremes in the Yangtze River Delta region of China

    Science.gov (United States)

    Zhong, Shi; Qian, Yun; Zhao, Chun; Leung, Ruby; Wang, Hailong; Yang, Ben; Fan, Jiwen; Yan, Huiping; Yang, Xiu-Qun; Liu, Dongqing

    2017-04-01

    The WRF-Chem model coupled with a single-layer urban canopy model (UCM) is integrated for 5 years at convection-permitting scale to investigate the individual and combined impacts of urbanization-induced changes in land cover and pollutant emissions on regional climate in the Yangtze River Delta (YRD) region in eastern China. Simulations with the urbanization effects reasonably reproduced the observed features of temperature and precipitation in the YRD region. Urbanization over the YRD induces an urban heat island (UHI) effect, which increases the surface temperature by 0.53 °C in summer and increases the annual heat wave days at a rate of 3.7 d yr-1 in the major megacities in the YRD, accompanied by intensified heat stress. In winter, the near-surface air temperature increases by approximately 0.7 °C over commercial areas in the cities but decreases in the surrounding areas. Radiative effects of aerosols tend to cool the surface air by reducing net shortwave radiation at the surface. Compared to the more localized UHI effect, aerosol effects on solar radiation and temperature influence a much larger area, especially downwind of the city cluster in the YRD. Results also show that the UHI increases the frequency of extreme summer precipitation by strengthening the convergence and updrafts over urbanized areas in the afternoon, which favor the development of deep convection. In contrast, the radiative forcing of aerosols results in a surface cooling and upper-atmospheric heating, which enhances atmospheric stability and suppresses convection. The combined effects of the UHI and aerosols on precipitation depend on synoptic conditions. Two rainfall events under two typical but different synoptic weather patterns are further analyzed. It is shown that the impact of urban land cover and aerosols on precipitation is not only determined by their influence on local convergence but also modulated by large-scale weather systems. For the case with a strong synoptic forcing

  8. Urbanization-induced urban heat island and aerosol effects on climate extremes in the Yangtze River Delta region of China

    Energy Technology Data Exchange (ETDEWEB)

    Zhong, Shi; Qian, Yun; Zhao, Chun; Leung, Ruby; Wang, Hailong; Yang, Ben; Fan, Jiwen; Yan, Huiping; Yang, Xiu-Qun; Liu, Dongqing

    2017-01-01

    The WRF-Chem model coupled with a single-layer urban canopy model (UCM) is integrated for 5 years at convection-permitting scale to investigate the individual and combined impacts of urbanization-induced changes in land cover and pollutant emissions on regional climate in the Yangtze River Delta (YRD) region in eastern China. Simulations with the urbanization effects reasonably reproduced the observed features of temperature and precipitation in the YRD region. Urbanization over the YRD induces an urban heat island (UHI) effect, which increases the surface temperature by 0.53 °C in summer and increases the annual heat wave days at a rate of 3.7 d yr-1 in the major megacities in the YRD, accompanied by intensified heat stress. In winter, the near-surface air temperature increases by approximately 0.7 °C over commercial areas in the cities but decreases in the surrounding areas. Radiative effects of aerosols tend to cool the surface air by reducing net shortwave radiation at the surface. Compared to the more localized UHI effect, aerosol effects on solar radiation and temperature influence a much larger area, especially downwind of the city cluster in the YRD.

    Results also show that the UHI increases the frequency of extreme summer precipitation by strengthening the convergence and updrafts over urbanized areas in the afternoon, which favor the development of deep convection. In contrast, the radiative forcing of aerosols results in a surface cooling and upper-atmospheric heating, which enhances atmospheric stability and suppresses convection. The combined effects of the UHI and aerosols on precipitation depend on synoptic conditions. Two rainfall events under two typical but different synoptic weather patterns are further analyzed. It is shown that the impact of urban land cover and aerosols on precipitation is not only determined by their influence on local convergence but also modulated by large-scale weather systems. For the case with a

  9. On the Impact of Wireless Jamming on the Distributed Secondary Microgrid Control

    DEFF Research Database (Denmark)

    Danzi, Pietro; Stefanovic, Cedomir; Meng, Lexuan

    2017-01-01

    control in a distributed fashion, relying on a communication system to achieve consensus among MG units. This paper shows that, if the system is not designed to cope with adversary communication impairments, then a malicious attacker can apply a simple jamming of a few units of the MG and thus compromise...

  10. Processing black mulberry into jam: effects on antioxidant potential and in vitro bioaccessibility.

    Science.gov (United States)

    Tomas, Merve; Toydemir, Gamze; Boyacioglu, Dilek; Hall, Robert D; Beekwilder, Jules; Capanoglu, Esra

    2017-08-01

    Black mulberries (Morus nigra) were processed into jam on an industrialised scale, including the major steps of: selection of frozen black mulberries, adding glucose-fructose syrup and water, cooking, adding citric acid and apple pectin, removing seeds, and pasteurisation. Qualitative and quantitative determinations of antioxidants in black mulberry samples were performed using spectrophotometric methods, as well as HPLC- and LC-QTOF-MS-based measurements. These analyses included the determination of total polyphenolic content, % polymeric colour, total and individual anthocyanin contents, antioxidant capacity, and in vitro bioaccessibility in processing samples. Jam processing led to a significant reduction in total phenolics (88%), total flavonoids (89%), anthocyanins (97%), and antioxidant capacity (88-93%) (P anthocyanin contents, determined using HPLC analysis, also showed a significant decrease (∼99% loss). In contrast, % recovery of bioaccessible total phenolics, anthocyanins, and antioxidant capacity (ABTS assay) increased after jam processing (16%, 12%, and 37%, respectively). Fruit processing resulted in losses of polyphenols, anthocyanins, and antioxidant capacity of black mulberry jam. Optimisation of food processing could help to protect the phenolic compounds in fruits which might be helpful for the food industry to minimise the antioxidant loss and improve the final product quality. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  11. Jamming in frictionless packings of spheres: determination of the critical volume fraction

    NARCIS (Netherlands)

    Göncü, F.; Göncü, F.; Duran Vinent, Orencio; Durán, O.; Masami, Nakagawa; Luding, Stefan

    2009-01-01

    The jamming transition in granular packings is characterized by a sudden change in the coordination number. In this work we investigate the evolution of coordination number as function of volume fraction for frictionless packings of spheres undergoing isotropic deformation. Using the results

  12. Magic at the Marketplace: Choice Blindness for the Taste of Jam and the Smell of Tea

    Science.gov (United States)

    Hall, Lars; Johansson, Petter; Tarning, Betty; Sikstrom, Sverker; Deutgen, Therese

    2010-01-01

    We set up a tasting venue at a local supermarket and invited passerby shoppers to sample two different varieties of jam and tea, and to decide which alternative in each pair they preferred the most. Immediately after the participants had made their choice, we asked them to again sample the chosen alternative, and to verbally explain why they chose…

  13. Monodisperse elastic shells: a 3D study of jammed granular matter and microencapsulation

    NARCIS (Netherlands)

    Jose, J.

    2014-01-01

    This thesis focusses on two, admittedly rather different, applications of spherical elastic shells. First in the field of microencapsulation as a smart container to encapsulate and release functional materials. Second, in jammed matter research as a model system to probe the microstructure and

  14. Modeling, Evaluation and Detection of Jamming Attacks in Time-Critical Wireless Applications

    Science.gov (United States)

    2014-08-01

    to be 4 and 8, respectively. We also set the retry limit to be 3. (iii) We use USRP N210 to set up three types of jammers: reactive, memoryless, and...periodic jammers. For reactive jamming, we use C++ code to directly control USRP to sense and transmit. The fastest reactive time is observed around

  15. Isochoric ideality in jammed random packings of non-spherical granular matter

    NARCIS (Netherlands)

    Kyrylyuk, A.V.|info:eu-repo/dai/nl/269067590; van der Haar, M.A.; Rossi, L.|info:eu-repo/dai/nl/314410376; Wouterse, A.|info:eu-repo/dai/nl/304841390; Philipse, A.P.|info:eu-repo/dai/nl/073532894

    2011-01-01

    Randomly packed particles in granular matter, ubiquitous in nature and industry, usually defy simple predictions for the optimal amorphous packing density because jammed granules are strongly correlated. While mixing different granular shapes seems to be a further complication, we discovered in

  16. Effect of ripening on the composition and the suitability for jam ...

    African Journals Online (AJOL)

    As part of an effort to solve the problem of post harvest losses of fruits, physicochemical characteristics of four mango varieties (Palmer, Améliorée, Mango and Keitt) were determined at two ripening stages. Their suitability for jam processing was also evaluated based on viscosity measurements. The pulps of pre-ripe ...

  17. Flow, turbulence, and drag associated with engineered log jams in a fixed-bed experimental channel

    Science.gov (United States)

    Engineered log jams (ELJs) have become attractive alternatives for river restoration and bank stabilization programs. Yet the effects of ELJs on turbulent flow and the fluid forces acting on the ELJs are not well known, and such information could inform design criteria. In this study, a fixed-bed ph...

  18. 21 CFR 150.161 - Artificially sweetened fruit preserves and jams.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Artificially sweetened fruit preserves and jams. 150.161 Section 150.161 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN..., spice extract. (2) A vinegar, lemon juice, lime juice, citric acid, lactic acid, malic acid, tartaric...

  19. Determination of mycotoxins in biscuits, dried fruits and fruit jams: an assessment of human exposure.

    Science.gov (United States)

    Škrbić, Biljana; Antić, Igor; Cvejanov, Jelena

    2017-06-01

    A reliable, fast and simple method using UHPLC-MS/MS was developed for the determination of aflatoxins B1 (AFB1), G1 (AFG1), B2 (AFB2) and G2 (AFG2), ochratoxin A (OTA), deoxynivalenol (DON), zearalenone (ZEA), HT-2 toxin and T-2 toxin in crude extracts of biscuits with fruit filling, cookies, dried fruits and fruit jams. The method was successfully demonstrated on 39 samples of biscuits with fruit filling, 34 cookies, 14 dried fruits and 10 fruit jams. The mycotoxins detected in biscuits samples were ZEA, OTA, T-2 and AFB1 with an average concentrations of positive samples of 2.64, 4.10, 8.13 and 1.32 µg kg(-1), respectively; while the mycotoxins detected in jam samples were AFB1, OTA, T-2 and AFB2 with an average concentrations of positive samples of 2.00, 17.7, 4.37 and 1.15 µg kg(-1), respectively. The results showed that the majority of samples were in compliance with relevant regulations. However in eight samples of biscuits and three samples of fig jam the contents of OTA were higher than the existing OTA limits. The combined dietary exposure of selected mycotoxins was estimated for the first time for children, adolescents and adults. The estimated combined dietary exposures were all lower than the proposed value assumed to predict a possible risk scenario.

  20. Changes in analytical and volatile compositions of red wines induced by pre-fermentation heat treatment of grapes.

    Science.gov (United States)

    Geffroy, Olivier; Lopez, Ricardo; Serrano, Eric; Dufourcq, Thierry; Gracia-Moreno, Elisa; Cacho, Juan; Ferreira, Vicente

    2015-11-15

    Experiments were carried out on Grenache, Carignan and Fer grapes in order to characterize the changes in nitrogen content of the musts, conventional enological parameters and aroma compounds of the wines induced by pre-fermentation heating of the grapes followed by alcoholic fermentation in liquid phase or in solid phase. In comparison to a standard vinification, we showed that a two-hour heat treatment at 70 °C induced a significant loss in several grape-derived aroma compounds (terpenols, norisoprenoids and some phenols) associated with an increase in α-terpineol, guaiacol and 2,6-dimethoxyphenol, which suggests thermal degradation. A significant increase in most of the ethyl esters, in acetates and in fatty acids were observed in wines fermented in liquid phase, together with a decrease in fusel alcohols. The substantial modification in the amino acid composition of the must seems to be a crucial element for the understanding of these changes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Monitoring the heat-induced structural changes of alkaline phosphatase by molecular modeling, fluorescence spectroscopy and inactivation kinetics investigations.

    Science.gov (United States)

    Dumitrașcu, Loredana; Stănciuc, Nicoleta; Aprodu, Iuliana; Ciuciu, Ana-Maria; Alexe, Petru; Bahrim, Gabriela Elena

    2015-10-01

    The heat induced conformational changes of calf alkaline phosphatase (ALP) were analyzed using different methods, based on fluorescence spectroscopy, molecular modeling and inactivation studies. Experimental studies were conducted in buffer solution in the temperature range between 25 and 70 °C. Molecular dynamic (MD) simulation provided details on thermally induced changes in ALP structure, highlighting that heating favored the hydrophobic exposure and important alteration of the catalytic site above 60 °C. Additional information to MD data were obtained by using different fluorescence spectroscopy methods, which revealed a complex mechanism of thermal denaturation. Therefore, the emissive properties indicated an unfolding of ALP at temperatures below 60 °C, whereas at higher temperatures, the polypeptides chains fold leading to a higher exposure of Trp residues. In order to establish a structure-function relationship, the results were correlated with inactivation studies of ALP in buffer at pH 9.0. The inactivation data were fitted using a first-order kinetic model, resulting in an activation energy value of 207.26 ± 21.68 kJ · mol(-1).

  2. Boundedness-preserving implicit correction of mesh-induced errors for VOF based heat and mass transfer

    Science.gov (United States)

    Hill, S.; Deising, D.; Acher, T.; Klein, H.; Bothe, D.; Marschall, H.

    2018-01-01

    Spatial discretisation of geometrically complex computational domains often entails unstructured meshes of general topology for Computational Fluid Dynamics (CFD). Mesh skewness is then typically encountered causing severe deterioration of the formal order of accuracy of the discretisation, or boundedness of the solution, or both. Particularly methods inherently relying on the accurate and bounded transport of sharp fields suffer from all types of mesh-induced skewness errors, namely both non-orthogonality and non-conjunctionality errors. This work is devoted to a boundedness-preserving strategy to correct for skewness errors arising from discretisation of advection and diffusion terms within the context of interfacial heat and mass transfer based on the Volume-of-Fluid methodology. The implementation has been accomplished using a second-order finite volume method with support for unstructured meshes of general topology. We examine and advance suitable corrections for the finite volume discretisation of a consistent single-field model, where both accurate and bounded transport due to diffusion and advection is crucial. In order to ensure consistency of both the volume fraction and the species concentration transport, i.e. to avoid artificial heat or species transfer, corrections are studied for both cases using distorted 2D meshes. The cross interfacial jump and adjacent sharp gradients of species concentration render the correction for skewness-induced diffusion and advection errors additionally demanding and has not so far been addressed in the literature.

  3. Postponement of incipient collapse due to work-induced heat stress by limited cooling

    Science.gov (United States)

    Blockley, W. V.

    1973-01-01

    Four subjects completed five treadmill training sessions under comfortable to cool conditions and were calibrated to find an optimum combination of speed and grade on the treadmill which would produce a metabolic rate of 2000 Btu-hr. Dressed in an Apollo liquid cooling garment, each man underwent a total of four experiments in which the rate of heat extraction from the liquid cooling garment was adjusted to an amount which would cause a storage within the body of 1000 Btu/hr. Physiological measurements included skin temperature at 9 locations, rectal and ear canal probes, and heart rate. The increases in tolerance time for the various subjects and the various methods of emergency cooling, ranged from a low of six minutes to a high of 48 minutes, or from 8 to 102% of the baseline tolerance times. The largest gains were achieved in a subject whose tolerance endpoint was atypical, and whose baseline heat tolerance was unsually low.

  4. Bio-heat transfer model of electroconvulsive therapy: Effect of biological properties on induced temperature variation.

    Science.gov (United States)

    de Oliveira, Marilia M; Wen, Paul; Ahfock, Tony

    2016-08-01

    A realistic human head model consisting of six tissue layers was modelled to investigate the behavior of temperature profile and magnitude when applying electroconvulsive therapy stimulation and different biological properties. The thermo-electrical model was constructed with the use of bio-heat transfer equation and Laplace equation. Three different electrode montages were analyzed as well as the influence of blood perfusion, metabolic heat and electric and thermal conductivity in the scalp. Also, the effect of including the fat layer was investigated. The results showed that temperature increase is inversely proportional to electrical and thermal conductivity increase. Furthermore, the inclusion of blood perfusion slightly drops the peak temperature. Finally, the inclusion of fat is highly recommended in order to acquire more realistic results from the thermo-electrical models.

  5. Allicin protects spinal cord neurons from glutamate-induced oxidative stress through regulating the heat shock protein 70/inducible nitric oxide synthase pathway.

    Science.gov (United States)

    Liu, Shu-Guang; Ren, Peng-Yu; Wang, Guo-Yu; Yao, Shu-Xin; He, Xi-Jing

    2015-01-01

    Allicin, the main biologically active compound derived from garlic, exerts a broad spectrum of pharmacological activities and is considered to have therapeutic potential in many neurological disorders. Using an in vitro spinal cord injury model induced by glutamate treatment, we sought to investigate the neuroprotective effects of allicin in primary cultured spinal cord neurons. We found that allicin treatment significantly attenuated glutamate-induced lactate dehydrogenase (LDH) release, loss of cell viability and apoptotic neuronal death. This protection was associated with reduced oxidative stress, as evidenced by decreased reactive oxygen species (ROS) generation, reduced lipid peroxidation and preservation of antioxidant enzyme activities. The results of western blot analysis showed that allicin decreased the expression of inducible nitric oxide synthase (iNOS), but had no effects on the expression of neuronal NOS (nNOS) following glutamate exposure. Moreover, allicin treatment significantly increased the expression of heat shock protein 70 (HSP70) at both mRNA and protein levels. Knockdown of HSP70 by specific targeted small interfere RNA (siRNA) not only mitigated allicin-induced protective activity, but also partially nullified its effects on the regulation of iNOS. Collectively, these data demonstrate that allicin treatment may be an effective therapeutic strategy for spinal cord injury, and that the potential underlying mechanism involves HSP70/iNOS pathway-mediated inhibition of oxidative stress.

  6. Local modification of GaAs nanowires induced by laser heating

    Energy Technology Data Exchange (ETDEWEB)

    Yazji, S; Zardo, I; Soini, M; Fontcuberta i Morral, A; Abstreiter, G [Walter Schottky Institut and Physik Department, Technische Universitaet Muenchen, Am Coulombwall 4, D-85748 Garching (Germany); Postorino, P, E-mail: ilaria.zardo@wsi.tum.de [Dipartimento di Fisica, Universita di Roma Sapienza, Piazzale Aldo Moro 5, I-00185 Roma (Italy)

    2011-08-12

    GaAs nanowires were heated locally under ambient air conditions by a focused laser beam which led to oxidation and formation of crystalline arsenic on the nanowire surface. Atomic force microscopy, photoluminescence and Raman spectroscopy experiments were performed on the same single GaAs nanowires in order to correlate their structural and optical properties. We show that the local changes of the nanowires act as a barrier for thermal transport which is of interest for thermoelectric applications.

  7. Involvement of heat shock proteins on Mn-induced toxicity in Caenorhabditis elegans.

    Science.gov (United States)

    Avila, Daiana Silva; Benedetto, Alexandre; Au, Catherine; Bornhorst, Julia; Aschner, Michael

    2016-11-02

    All living cells display a rapid molecular response to adverse environmental conditions, and the heat shock protein family reflects one such example. Hence, failing to activate heat shock proteins can impair the cellular response. In the present study, we evaluated whether the loss of different isoforms of heat shock protein (hsp) genes in Caenorhabditis elegans would affect their vulnerability to Manganese (Mn) toxicity. We exposed wild type and selected hsp mutant worms to Mn (30 min) and next evaluated further the most susceptible strains. We analyzed survival, protein carbonylation (as a marker of oxidative stress) and Parkinson's disease related gene expression immediately after Mn exposure. Lastly, we observed dopaminergic neurons in wild type worms and in hsp-70 mutants following Mn treatment. Analysis of the data was performed by one-way or two way ANOVA, depending on the case, followed by post-hoc Bonferroni test if the overall p value was less than 0.05. We verified that the loss of hsp-70, hsp-3 and chn-1 increased the vulnerability to Mn, as exposed mutant worms showed lower survival rate and increased protein oxidation. The importance of hsp-70 against Mn toxicity was then corroborated in dopaminergic neurons, where Mn neurotoxicity was aggravated. The lack of hsp-70 also blocked the transcriptional upregulation of pink1, a gene that has been linked to Parkinson's disease. Taken together, our data suggest that Mn exposure modulates heat shock protein expression, particularly HSP-70, in C. elegans. Furthermore, loss of hsp-70 increases protein oxidation and dopaminergic neuronal degeneration following manganese exposure, which is associated with the inhibition of pink1 increased expression, thus potentially exacerbating the vulnerability to this metal.

  8. Amelioration of heat stress induced disturbances of antioxidant defense system in chicken by brahma rasayana.

    Science.gov (United States)

    Ramnath, V; Rekha, P S; Sujatha, K S

    2008-03-01

    Since the range of comfort zone or thermo neutral zone of domestic chickens is narrow, they become easily susceptible to heat and cold environmental stress. We evaluated Brahma Rasayana (BR) supplementation on concentrations of certain oxidative stress markers associated with heat stress. A total of 48 egg type male chickens of local strain were divided into six groups (n = 8) for the study. Three groups were fed with BR orally at the rate of 2 g/kg bw daily for 10 days prior to and during the period of experiment. Two of the four groups that were exposed to heat stress (HST i.e. to a temperature of 40 +/- 1 degrees C and relative humidity of 80 +/- 5% in an environmental chamber) for 4 h daily for 5 or 10 days, received BR orally. The other two groups remained as BR treated and untreated non-heat stressed (NHST) controls. There was a significant (P < 0.05) increase in the activities of antioxidant enzymes in blood such as catalase (CAT) and superoxide dismutase (SOD), as well as liver CAT, glutathione peroxidase (GPX) and glutathione reductase (GR) in NHST-BR treated and HST-BR treated (both 5 and 10 days) chickens when compared with untreated controls. A great deal of significant (P < 0.05) variations were seen in serum and liver reduced glutathione (GSH) concentration in NHST-BR treated and HST-BR treated (both 5 and 10 days) chickens. Serum and liver lipid peroxidation levels were found to be significantly (P < 0.05) higher in HST-untreated (both 5 and 10 days) chickens when compared with other groups. Thus BR supplementation during HST brings about enhanced action of enzymatic and non-enzymatic antioxidants, which nullified the undesired side effects of free radicals that are generated during HST.

  9. Amelioration of Heat Stress Induced Disturbances of Antioxidant Defense System in Chicken by Brahma Rasayana

    Directory of Open Access Journals (Sweden)

    V. Ramnath

    2008-01-01

    Full Text Available Since the range of comfort zone or thermo neutral zone of domestic chickens is narrow, they become easily susceptible to heat and cold environmental stress. We evaluated Brahma Rasayana (BR supplementation on concentrations of certain oxidative stress markers associated with heat stress. A total of 48 egg type male chickens of local strain were divided into six groups (n = 8 for the study. Three groups were fed with BR orally at the rate of 2 g/kg bw daily for 10 days prior to and during the period of experiment. Two of the four groups that were exposed to heat stress (HST i.e. to a temperature of 40 ± 1°C and relative humidity of 80 ± 5% in an environmental chamber for 4 h daily for 5 or 10 days, received BR orally. The other two groups remained as BR treated and untreated non-heat stressed (NHST controls. There was a significant (P < 0.05 increase in the activities of antioxidant enzymes in blood such as catalase (CAT and superoxide dismutase (SOD, as well as liver CAT, glutathione peroxidase (GPX and glutathione reductase (GR in NHST-BR treated and HST-BR treated (both 5 and 10 days chickens when compared with untreated controls. A great deal of significant (P < 0.05 variations were seen in serum and liver reduced glutathione (GSH concentration in NHST-BR treated and HST-BR treated (both 5 and 10 days chickens. Serum and liver lipid peroxidation levels were found to be significantly (P < 0.05 higher in HST-untreated (both 5 and 10 days chickens when compared with other groups. Thus BR supplementation during HST brings about enhanced action of enzymatic and non-enzymatic antioxidants, which nullified the undesired side effects of free radicals that are generated during HST.

  10. Mitochondrial reactive oxygen species production by fish muscle mitochondria: Potential role in acute heat-induced oxidative stress.

    Science.gov (United States)

    Banh, Sheena; Wiens, Lilian; Sotiri, Emianka; Treberg, Jason R

    2016-01-01

    Acute heat challenge is known to induce cell-level oxidative stress in fishes. Mitochondria are well known for the capacity to make reactive oxygen species (ROS) and as such are often implicated as a source of the oxidants associated with this thermally-induced oxidative stress. This implication is often asserted, despite little direct data for mitochondrial ROS metabolism in fishes. Here we characterize mitochondrial ROS metabolism in three Actinopterygian fish species at two levels, the capacity for superoxide/H2O2 production and the antioxidant thiol-reductase enzyme activities. We find that red muscle mitochondria from all three species have measurable ROS production and respond to different assay conditions consistent with what might be anticipated; assuming similar relative contributions from difference ROS producing sites as found in rat skeletal muscle mitochondria. Although there are species and assay specific exceptions, fish mitochondria may have a greater capacity to produce ROS than that found in the rat when either normalized to respiratory capacity or determined at a common assay temperature. The interspecific differences in ROS production are not correlated with thiol-based antioxidant reductase activities. Moreover, mimicking an acute in vivo heat stress by comparing the impact of increasing assay temperature on these processes in vitro, we find evidence supporting a preferential activation of mitochondrial H2O2 production relative to the increase in the capacity of reductase enzymes to supply electrons to the mitochondrial matrix peroxidases. This supports the contention that mitochondria may be, at least in part, responsible for the ROS that lead to oxidative stress in fish tissues exposed to acute heat challenge. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Comparison of heat induced damage at the saphenofemoral junction after ablation with 1,470 nm laser or radiofrequency.

    Science.gov (United States)

    Ozcinar, Evren; Cakici, Mehmet; Korun, Oktay; Han, Unsal; Kiziltepe, Ugursay

    2017-03-01

    The aim of this study was to evaluate the heat induced damage at the saphenofemoral junction level according to histopathological changes after radiofrequency or 1,470 nm radial tip laser ablation. Varicose vein segments of 6-10 mm in diameter were exposed to radiofrequency (Closure Fast catheter, 7 cm heat segment, one cycle, 15 seconds, 10 Watt, 120 °C) or laser ablation (1,470 nm radial tip, continuous wave, vein diameter: 6 cm/8 cm/10 cm-power: 10 Watt-pullback speed: 2.2 mm/s, 1.7 mm/s, 1.3 mm/s-LEED: 45J/cm, 60J/cm, 75J/cm-EFE 25J/cm(2), respectively). Approximate 2 cm segments of the vein were left untreated, then histopathological examinations of the untouched segments (5 slices: level 1 - furthest segment, level 2 - nearest segment) for heat induced damage were performed. A total damage scoring system was established, including the presence of endothelial swelling, intimal thickening, cellular vacuolisation in the muscle layer, oedema in the tunica media, and extent of necrosis. At level 1, the furthest segment of the specimen, there was no significant difference between the laser and control group, while the total damage score of the radiofrequency group was significantly higher than the control group (p laser group at level 1 (p ablation seems to cause more histological damage than laser ablation in this ex vivo study. Further in vivo studies are necessary, in order to validate these findings.

  12. Repair of radiation-induced heat-labile sites is independent of DNA-PKcs, XRCC1 or PARP

    Energy Technology Data Exchange (ETDEWEB)

    Stenerl& #246; w, Bo; Karlsson, Karin H.; Radulescu, Irina; Rydberg, Bjorn; Stenerlow, Bo

    2008-04-29

    Ionizing radiation induces a variety of different DNA lesions: in addition to the most critical DNA damage, the DSB, numerous base alterations, SSBs and other modifications of the DNA double-helix are formed. When several non-DSB lesions are clustered within a short distance along DNA, or close to a DSB, they may interfere with the repair of DSBs and affect the measurement of DSB induction and repair. We have previously shown that a substantial fraction of DSBs measured by pulsed-field gel electrophoresis (PFGE) are in fact due to heat-labile sites (HLS) within clustered lesions, thus reflecting an artifact of preparation of genomic DNA at elevated temperature. To further characterize the influence of HLS on DSB induction and repair, four human cell lines (GM5758, GM7166, M059K, U-1810) with apparently normal DSB rejoining were tested for bi-phasic rejoining after gamma irradiation. When heat-released DSBs were excluded from the measurements the fraction of fast rejoining decreased to less than 50% of the total. However, neither the half-times of the fast (t{sub 1/2} = 7-8 min) or slow (t{sub 1/2} = 2.5 h) DSB rejoining were changed significantly. At t=0 the heat-released DSBs accounted for almost 40% of the DSBs, corresponding to 10 extra DSB/cell/Gy in the initial DSB yield. These heat-released DSBs were repaired within 60-90 min in all tested cells, including M059K cells treated with wortmannin or DNA-PKcs defect M059J cells. Furthermore, cells lacking XRCC1 or Poly(ADP-ribose) polymerase-1 (PARP-1) rejoined both total DSBs and heat-released DSBs similar to normal cells. In summary, the presence of heat-labile sites have a substantial impact on DSB induction yields and DSB rejoining rates measured by pulsed-field gel electrophoresis, and HLS repair is independent of DNA-PKcs, XRCC1 and PARP.

  13. Heat stress and age induced maternal effects on wing size and shape in parthenogenetic Drosophila mercatorum

    DEFF Research Database (Denmark)

    Andersen, DH; Pertoldi, C; Scali, V

    2005-01-01

    Maternal effects on progeny wing size and shape in a homozygous parthenogenetic strain of Drosophila mercatorum were investigated. The impact of external maternal factors (heat stress) and the impact of internal maternal factors (different maternal and grand maternal age) were studied. The offspr......Maternal effects on progeny wing size and shape in a homozygous parthenogenetic strain of Drosophila mercatorum were investigated. The impact of external maternal factors (heat stress) and the impact of internal maternal factors (different maternal and grand maternal age) were studied....... The offspring developed under identical environmental conditions, and due to lack of genetic variation any phenotypic difference among offspring could be ascribed to maternal effects. Wing size was estimated by centroid size, shape was analysed with the Procrustes geometric morphometric method and variation...... in landmark displacement was visualized by principal component analysis. Both kinds of maternal effects had a significant impact on progeny wing size and shape. Maternal heat stress led to the same pattern of response in size and shape among the progeny, with increased difference between the control group...

  14. Studies of Deteriorated Heat Transfer in Prismatic Cores Stemming from Irradiation-Induced Geometry Distortion

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Brian G. [Idaho State Univ., Pocatello, ID (United States); Schultz, Richard R. [Idaho National Lab. (INL), Idaho Falls, ID (United States); McEligot, Don M. [Univ. of Idaho, Moscow, ID (United States); McCreery, Glenn [Battelle Energy Alliance, LLC, Idaho Falls, ID (United States)

    2015-08-31

    A reference design for the Next Generation Nuclear Plant (NGNP) is to use General Atomics Modular High Temperature Gas-cooled Reactor (MHTGR). For such a configuration in normal operation, the helium coolant flow proceeds from the upper plenum to the lower plenum principally through the core coolant channels and the interstitial gaps (bypass flow) that separate the prismatic blocks from one another. Only the core prismatic blocks have coolant channels. The interstitial gaps are present throughout the core, the inner reflector region, and the out reflector region. The bypass flows in a prismatic gas-cooled reactor (GCR) are of potential concern because they reduce the desired flow rates in the coolant channels and, thereby, can increase outlet gas temperatures and maximum fuel temperatures. Consequently, it is appropriate to account for bypass flows in reactor thermal gas dynamic analyses. The objectives of this project include the following: fundamentally understand bypass flow and heat transfer at scaled, undistorted conditions and with geometry distortions; develop improved estimates of associated loss coefficients, surface friction and heat transfer for systems and network codes; and obtain related data for validation of CFD (computational fluid dynamic) or system (e.g., RELAP5) codes which can be employed in predictions for a GCR for normal power, reduced power, and residual heat removal operations.

  15. Heating-induced transition of Potyvirus Potato Virus A coat protein into β-structure.

    Science.gov (United States)

    Ksenofontov, Alexander L; Parshina, Evgenia Yu; Fedorova, Natalia V; Arutyunyan, Alexander M; Rumvolt, Reet; Paalme, Viiu; Baratova, Ludmila A; Järvekülg, Lilian; Dobrov, Eugeny N

    2016-01-01

    In our previous communication, we have reported that virions of plant Potyvirus Potato Virus A (PVA) have a peculiar structure characterized by high content of disordered regions in intravirus coat protein (CP). In this report, we describe unusual properties of the PVA CP. With the help of a number of physicochemical methods, we have observed that the PVA CP just released from the virions by heating at 60-70 °C undergoes association into oligomers and transition to β- (and even cross-β-) conformation. Transition to β-structure on heating has been recently reported for a number of viral and non-viral proteins. The PVA CP isolated by LiCl method was also transformed into cross-β-structure on heating to 60 °C. Using the algorithms for protein aggregation prediction, we found that the aggregation-prone segments should be located in the central region of a PVA CP molecule. Possibly this transition mimics some functions of PVA CP in the virus life cycle in infected plants.

  16. Environmental heat stress induces epigenetic transgenerational inheritance of robustness in parthenogenetic Artemia model.

    Science.gov (United States)

    Norouzitallab, Parisa; Baruah, Kartik; Vandegehuchte, Michiel; Van Stappen, Gilbert; Catania, Francesco; Vanden Bussche, Julie; Vanhaecke, Lynn; Sorgeloos, Patrick; Bossier, Peter

    2014-08-01

    The notion that phenotypic traits emerging from environmental experiences are heritable remains under debate. However, the recent report of nonmendelian transgenerational epigenetic inheritance, i.e., the inheritance of traits not determined by the DNA sequence, might make such a phenomenon plausible. In our study, by carrying out common garden experiments, we could provide clear evidences that, on exposure to nonlethal heat shocks, a parental population of parthenogenetic (all female) Artemia (originating from one single female) experiences an increase in levels of Hsp70 production, tolerance toward lethal heat stress, and resistance against pathogenic Vibrio campbellii. Interestingly, these acquired phenotypic traits were transmitted to three successive generations, none of which were exposed to the parental stressor. This transgenerational inheritance of the acquired traits was associated with altered levels of global DNA methylation and acetylated histones H3 and H4 in the heat-shocked group compared to the control group, where both the parental and successive generations were reared at standard temperature. These results indicated that epigenetic mechanisms, such as global DNA methylation and histones H3 and H4 acetylation, have particular dynamics that are crucial in the heritability of the acquired adaptive phenotypic traits across generations. © FASEB.

  17. Recrystallization and grain growth induced by ELMs-like transient heat loads in deformed tungsten samples

    Science.gov (United States)

    Suslova, A.; El-Atwani, O.; Sagapuram, D.; Harilal, S. S.; Hassanein, A.

    2014-11-01

    Tungsten has been chosen as the main candidate for plasma facing components (PFCs) due to its superior properties under extreme operating conditions in future nuclear fusion reactors such as ITER. One of the serious issues for PFCs is the high heat load during transient events such as ELMs and disruption in the reactor. Recrystallization and grain size growth in PFC materials caused by transients are undesirable changes in the material, since the isotropic microstructure developed after recrystallization exhibits a higher ductile-to-brittle transition temperature which increases with the grain size, a lower thermal shock fatigue resistance, a lower mechanical strength, and an increased surface roughening. The current work was focused on careful determination of the threshold parameters for surface recrystallization, grain growth rate, and thermal shock fatigue resistance under ELM-like transient heat events. Transient heat loads were simulated using long pulse laser beams for two different grades of ultrafine-grained tungsten. It was observed that cold rolled tungsten demonstrated better power handling capabilities and higher thermal stress fatigue resistance compared to severely deformed tungsten. Higher recrystallization threshold, slower grain growth, and lower degree of surface roughening were observed in the cold rolled tungsten.

  18. (+-Naloxone inhibits morphine-induced chemotaxis via prevention of heat shock protein 90 cleavage in microglia

    Directory of Open Access Journals (Sweden)

    Ru-Yin Tsai

    2015-05-01

    Conclusion: Based on the findings of the present study, we suggest that (+-naloxone inhibits morphine-induced microglia activation by regulating HDAC6-dependent α-tubulin deacetylation and HSP90 fragmentation.

  19. Fluid shear stress induces the phosphorylation of small heat shock proteins in vascular endothelial cells

    National Research Council Canada - National Science Library

    Li, S; Piotrowicz, R S; Levin, E G; Shyy, Y J; Chien, S

    1996-01-01

    .... In bovine aortic endothelial cells stably transfected with the wild-type human HSP27 gene, shear stress induced the phosphorylation of both the exogenous human HSP27 and the endogenous bovine HSP25...

  20. Heat shock-induced apoptosis in germ line cells of Triatoma infestans Klug

    Directory of Open Access Journals (Sweden)

    Maria Luiza S. Mello

    2000-06-01

    Full Text Available The survival of Triatoma infestans and of somatic cells from this species is affected by heat shock. In this study, we examined the cell death responses of male germ line cells from 5th instar nymphs 7 and 30 days after heat shock exposure (40ºC, 1 h. The preparations were stained by the Feulgen reaction and the TUNEL immunocytochemical assay. Apoptosis was elicited by heat shock, with positive TUNEL responses in spermatogonial chromatin and chromosomes, spermatids and sperm cells. Spermatogonia were most affected seven days after the shock whereas some spermatids and sperm cells exhibited DNA fragmentation only thirty days after heat shock. The rate of cell death varied among the cells. In some cases, cellular differentiation was unaffected by heat shock, with DNA fragmentation occurring towards the end of spermatogenesis.Uma vez que em Triatoma infestans a sobrevivência de células somáticas e dos próprios espécimes é afetada por choques de temperatura, foi estudada a indução de morte celular em células da linhagem germinativa masculina de ninfas de 5o. estadio 7 e 30 dias após choque de 1 h a 40ºC. Os preparados foram submetidos à reação de Feulgen e ao teste imunocitoquímico TUNEL. Foi encontrada apoptose induzida pelo choque de temperatura, sendo que respostas positivas ao TUNEL foram vistas na cromatina e em cromossomos de espermatogônias e em espermátides e espermatozóides. As espermatogônias foram afetadas principalmente 7 dias após o choque, enquanto algumas espermátides e espermatozóides exibiram fragmentação de DNA apenas 30 dias após o choque. Admite-se que a velocidade com a qual avança o processo de morte celular varie nessas células. Diferenciação celular não é impedida em parte das células afetadas, permitindo que a fragmentação de seu DNA ocorra mais tardiamente, inclusive no fim da espermatogênese.

  1. Wildland Fire Induced Heating of Dome 375 Perma-Con®

    Energy Technology Data Exchange (ETDEWEB)

    Flores, Eugene Michael [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-08-09

    AET-1 was tasked by ADEM with determining the temperature rise in the drum contents of drums stored in the Dome 375 Perma-Con® at TA-54 given a wildland fire. The wildland fire causes radiative and convective heating on the Perma-Con® exterior. The wildland fire time histories for the radiative and convective heating environment were provided to AET-1 by EES-16. If the calculated temperature rise results in a drum content temperature over 40 °C, then ADEM desires a design solution to ensure the peak temperature remains below 40 °C. An axi-symmetric FE simulation was completed to determine the peak temperature of the contents of a drum stored in the Dome 375 Perma-Con® during a wildland fire event. Three wildland fire time histories for the radiative and convective heat transfer were provided by EES-16 and were inputs for the FE simulation. The maximum drum content temperature reached was found to be 110 °C while using inputs from the SiteG_2ms_4ign_wind_from_west.xlsx time history input and not including the SWB in the model. Including the SWB in the results in a peak drum content temperature of 61 °C for the SiteG_2ms_4ign_wind_from_west.xlsx inputs. EES-16 decided that by using fuel mitigation efforts, such as mowing the grass and shrubs near the Perma-Con® they could reduce the shrub/grass fuel loading near the Perma-Con® from 1.46 kg/m2 to 0.146 kg/m2 and by using a less conservative fuel loading for the debris field inside the Dome 375 perimeter, reducing it from 0.58 kg/m2 to 0.058 kg/m2 in their model. They also greatly increased the resolution of their radiation model and increased the accuracy of their model’s required convergence value. Using this refined input the maximum drum content temperature was found to be 28 °C with no SWB present in the model. Additionally, this refined input model was modified to include worst case emissivity values for the concrete, drum and Perma-Con® interior, along with adding a

  2. Physico-chemical characteristics and antioxidant activity of goji fruits jam and jelly during storage

    Directory of Open Access Journals (Sweden)

    Daniela ISTRATI

    2013-12-01

    Full Text Available Since the 1990s, when the news about antioxidants and their benefits to health has begun to spread to the general public, statements about the benefits of antioxidants ranged from preventing colds to cancer treatment. Fruits and vegetables are excellent sources of antioxidants. Since the beginning of the 21st century, goji berries have become increasingly popular in Europe and North America and have been promoted in advertisements and in the media as an anti-aging remedy. Goji is a relatively new name given to Lycium Barbarum and Lycium chinense, two nearby species, with a long history of use as medicinal and food plants in East Asia, particularly in China. In the present paper are presented analysis results of Goji fruits and food products made from goji fruits (jam and jelly. Storage conditions are important factors for jams and jelly quality. The objective of this study was to monitor the physicochemical stability, antioxidant activity and sensorial profile of goji fruits jam and jelly. Special attention was paid to total phenolic and flavonoid content, antioxidant activity, total soluble solids, titratable acidity, pH and sensorial characteristics. Our results showed the antioxidant activity of the goji fruit, values which correlate well with the results obtained for total phenolic (351±7.25 mg GAE/100g and flavonoid content (53.06±1.23 mg QE/100g. The antioxidant activity of the goji fruits was maintained also in the finished products obtained in the present study jam (60.98 % and jelly (41.96 %. Both goji fruits jam and goji fruits jelly showed no significant variations of physico-chemical characteristics and sensorial parameter scores after storage at refrigeration temperature for 10 days.

  3. Innovative Engagement with NASA Data: Best Practices in Hosting a Space-Themed Game Jam Event

    Science.gov (United States)

    Mader, M. M.

    2015-12-01

    Planetary mission milestones provide key opportunities to engage the public in the day to day work and showcase the value, wonder, and innovative technologies of planetary exploration. The Royal Ontario Museum (ROM), Canada, is designing unique experiences that will allow new audiences to relate to planetary mission results, through direct interaction with planetary materials and data. Through co-creation and collaboration, we aim to encourage STEM and STEAM learning through interactive programs that are interest driven by the participants. Based on these principles, the ROM, in collaboration with the University of Toronto, is hosting a Game Jam event (see http://www.rom.on.ca/en/activities-programs/programs/game-jam). A Game Jam invites creative, motivated, and inspired game developers to work in a collaborative environment over the course of 3 days to create games linked to a theme. This year's theme is "Space Rocks". Video games, fuelled by actual mission data, capture public interest in space and science in a unique and powerful way, giving us new insight into the real challenges we have on Earth and in space. The ROM Game Jam will allow 100 game developers to draw inspiration from our collection of over 100,000 rocks, minerals, and gems, including over 500 martian, lunar, and asteroidal meteorites. Participants will learn about the history of these specimens directly from ROM experts. NASA datasets related to our collection will be highlighted and curated for this event. The games produced during the Game Jam will live on and be featured online and at numerous ROM events throughout the year. Our presentation will highlight lessons learned from this experience, best practices, and future plans.

  4. Functional regions of HpaXm as elicitors with specific heat tolerance induce the hypersensitive response or plant growth promotion in nonhost plants.

    Science.gov (United States)

    Liu, Yue; Zhou, Xiaoyun; Liu, Wenbo; Xiong, Xiaohui; Lv, Chuyang; Zhou, Xiang; Miao, Weiguo

    2018-01-01

    HpaXm produced by the cotton leaf blight bacterium Xanthomonas citri subsp. malvacearum is a novel harpin elicitor of the induced hypersensitive response (HR) in tobacco. We investigated whether fragments of HpaXm, compared with fragments of Hpa1Xoo, are sufficient for HR or plant growth promotion (PGP) elicitation using four synthetic peptides (HpaXm35-51, HpaXm10-39, Hpa1Xoo36-52 and Hpa1Xoo10-40). We also heated the fragments to determine the heat tolerance of the functional fragments. HpaXm35-51 and Hpa1Xoo36-52 induced hypersensitive response (HR). Bursts of reactive oxygen intermediates (ROI) induced by HpaXm35-51 and Hpa1Xoo36-52 were earlier and stronger than those induced by HpaXm and Hpa1Xoo. In plants treated with HpaXm35-51 or Hpa1Xoo36-52, the expression of the HR marker genes Hin1 and Hsr203J and the active oxygen metabolism related gene AOX were significantly upregulated. These findings suggest that the predicted α-helical structures of the HpaXm35-51 and Hpa1Xoo36-52 fragments are crucial for HR. PGP result by soaking seeds in unheated/heated HpaXm10-39 or Hpa1Xoo10-40 solution prior to transfer, which obviously enhances root growth and the aerial parts of plants. The PGP related gene NtEXP6 was greatly enhanced when plants were sprayed with a solution of HpaXm10-39 or Hpa1Xoo10-40; heated fragment treatments induced higher levels of NtEXP6 expression than unheated HpaXm fragments. In addition, HR marker genes induced by the heated fragments had lower expression levels than when induced with unheated HpaXm fragments. Moreover, the expression levels of HR marker genes and PGP related genes induced by treatment with Hpa1Xoo fragments before or after heating were the opposite of those induced by HpaXm fragments. Different functional fragments of harpin and different harpins with the same functional region have different degrees of heat tolerance. Therefore, the heat resistance of harpin is conservative, but the degree of heat tolerance of the

  5. Shape effects on time-scale divergence at athermal jamming transition of frictionless non-spherical particles

    Science.gov (United States)

    Yuan, Ye; Jin, Weiwei; Liu, Lufeng; Li, Shuixiang

    2017-10-01

    The critical behaviors of a granular system at the jamming transition have been extensively studied from both mechanical and thermodynamic perspectives. In this work, we numerically investigate the jamming behaviors of a variety of frictionless non-spherical particles, including spherocylinder, ellipsoid, spherotetrahedron and spherocube. In particular, for a given particle shape, a series of random configurations at different fixed densities are generated and relaxed to minimize interparticle overlaps using the relaxation algorithm. We find that as the jamming point (i.e., point J) is approached, the number of iteration steps (defined as the ;time-scale; for our systems) required to completely relax the interparticle overlaps exhibits a clear power-law divergence. The dependence of the detailed mathematical form of the power-law divergence on particle shapes is systematically investigated and elucidated, which suggests that the shape effects can be generally categorized as elongation and roundness. Importantly, we show the jamming transition density can be accurately determined from the analysis of time-scale divergence for different non-spherical shapes, and the obtained values agree very well with corresponding ones reported in literature. Moreover, we study the plastic behaviors of over-jammed packings of different particles under a compression-expansion procedure and find that the jamming of ellipsoid is much more robust than other non-spherical particles. This work offers an alternative approximate procedure besides conventional packing algorithms for studying athermal jamming transition in granular system of frictionless non-spherical particles.

  6. Extracellular heat-shock protein 70 aggravates cerulein-induced pancreatitis through toll-like receptor-4 in mice

    Institute of Scientific and Technical Information of China (English)

    SONG Jun-min; WANG Rong; LIU Hong-xiang; LI Yuan; ZENG Yu-jian; ZHOU Zong-guang; LIU Hai-yi; XU Bing; WANG Ling; ZHOU Bin

    2008-01-01

    Background In patients suffering from acute pancreatitis, the pathogenesis is not completely understood, and several recent studies in vitro suggested that heat shock proteins might play an important role in cell signaling. To investigate the possible role of extracellular heat shock protein 70 (Hsp70) in pancreatitis, toll-like receptor-4 (TLR4)-deficient and wild-type mice were administered with exogenous Hsp70 during the course of cerulein-induced pancreatitis (CIP).Methods Acute pancreatitis was induced by 5 intraperitoneal injections of cerulein at hourly intervals, and then treated with recombinant Hsp70 through the caudal vein 4 hours after the start of cerulein injections. Subsequently serum amylase and serum cytokines levels were detected. Histologic alteration of the pancreas was evaluated. Tumor necrosis factor alpha (TNF-a) concentrations and myeloperoxidase (MPO) activity in both pancreas and lungs were analyzed. The nuclear factor kappa B (NF-KB) activation in pancreatic tissue was measured using a sensitive RelA enzyme-linked immunosorbent assay.Results Treatment with recombinant Hsp70 to wild-type mice in CIP resulted in significant aggravation of inflammation in pancreas, elevated levels of serum cytokines, up-regulation of pulmonary MPO activity and increase of lung tissues TNF-α concentrations. In contrast, treatment with Hsp70 to TLR4-deficient mice had little effect on serum cytokines levels, pancreatic inflammation, pulmonary MPO activity and TNF-a concentrations.Conclusions The results suggest that extracellular HspTO might induce systemic inflammatory response syndrome (SIRS)-Iike response in vivo and TLR4 might be involved in the Hsp70-mediated activation of inflammatory reaction in the progression of CIP without infection.

  7. Latent heat induced rotation limited aggregation in 2D ice nanocrystals

    Science.gov (United States)

    Bampoulis, Pantelis; Siekman, Martin H.; Kooij, E. Stefan; Lohse, Detlef; Zandvliet, Harold J. W.; Poelsema, Bene

    2015-07-01

    The basic science responsible for the fascinating shapes of ice crystals and snowflakes is still not understood. Insufficient knowledge of the interaction potentials and the lack of relevant experimental access to the growth process are to blame for this failure. Here, we study the growth of fractal nanostructures in a two-dimensional (2D) system, intercalated between mica and graphene. Based on our scanning tunneling spectroscopy data, we provide compelling evidence that these fractals are 2D ice. They grow while they are in material contact with the atmosphere at 20 °C and without significant thermal contact to the ambient. The growth is studied in situ, in real time and space at the nanoscale. We find that the growing 2D ice nanocrystals assume a fractal shape, which is conventionally attributed to Diffusion Limited Aggregation (DLA). However, DLA requires a low mass density mother phase, in contrast to the actual currently present high mass density mother phase. Latent heat effects and consequent transport of heat and molecules are found to be key ingredients for understanding the evolution of the snow (ice) flakes. We conclude that not the local availability of water molecules (DLA), but rather them having the locally required orientation is the key factor for incorporation into the 2D ice nanocrystal. In combination with the transport of latent heat, we attribute the evolution of fractal 2D ice nanocrystals to local temperature dependent rotation limited aggregation. The ice growth occurs under extreme supersaturation, i.e., the conditions closely resemble the natural ones for the growth of complex 2D snow (ice) flakes and we consider our findings crucial for solving the "perennial" snow (ice) flake enigma.

  8. Fluctuation-induced heat release from temperature-quenched nuclear spins near a quantum critical point.

    Science.gov (United States)

    Kim, Y H; Kaur, N; Atkins, B M; Dalal, N S; Takano, Y

    2009-12-11

    At a quantum critical point (QCP)--a zero-temperature singularity in which a line of continuous phase transition terminates--quantum fluctuations diverge in space and time, leading to exotic phenomena that can be observed at nonzero temperatures. Using a quantum antiferromagnet, we present calorimetric evidence that nuclear spins frozen in a high-temperature nonequilibrium state by temperature quenching are annealed by quantum fluctuations near the QCP. This phenomenon, with readily detectable heat release from the nuclear spins as they are annealed, serves as an excellent marker of a quantum critical region around the QCP and provides a probe of the dynamics of the divergent quantum fluctuations.

  9. Universal Coherence-Induced Power Losses of Quantum Heat Engines in Linear Response.

    Science.gov (United States)

    Brandner, Kay; Bauer, Michael; Seifert, Udo

    2017-10-27

    We identify a universal indicator for the impact of coherence on periodically driven quantum devices by dividing their power output into a classical contribution and one stemming solely from superpositions. Specializing to Lindblad dynamics and small driving amplitudes, we derive general upper bounds on both the coherent and the total power of cyclic heat engines. These constraints imply that, for sufficiently slow driving, coherence inevitably leads to power losses in the linear-response regime. We illustrate our theory by working out the experimentally relevant example of a single-qubit engine.

  10. Crystal Growth of Thiol-Stabilized Gold Nanoparticles by Heat-Induced Coalescence

    Directory of Open Access Journals (Sweden)

    Moon SookYoung

    2010-01-01

    Full Text Available Abstract A monolayer of dodecanethiol-stabilized gold nanoparticles changed into two-dimensional and three-dimensional self-organized structures by annealing at 323 K. Subsequent crystal growth of gold nanoparticles occurred. Thiol molecules, although chemisorbed, form relatively unstable bonds with the gold surface; a few thiols desorbed from the surface and oxidized to disulfides at 323 K, because the interaction energy between thiol macromolecules is larger than that between a thiol and a nanoparticle. The gold nanoparticles approached each other and grew into large single or twinned crystals because of the van der Waals attraction and the heat generated by the exothermic formation of disulfides.

  11. Exercise- and methylcholine-induced sweating responses in older and younger men: effect of heat acclimation and aerobic fitness

    Science.gov (United States)

    Inoue, Y.; Havenith, George; Kenney, W. Larry; Loomis, Joseph L.; Buskirk, Elsworth R.

    The purpose of this investigation was to examine the effects of aging and aerobic fitness on exercise- and methylcholine-induced sweating responses during heat acclimation. Five younger [Y group - age: 23+/-1 (SEM) years; maximal oxygen consumption (V.O2max): 47+/-3 ml.kg-1.min-1], four highly fit older (HO group - 63+/-3 years; 48+/-4 ml.kg-1.min-1) and five normally fit older men (NO group - 67+/-3 years; 30+/-1 ml.kg-1.min-1) who were matched for height, body mass and percentage fat, were heat acclimated by daily cycle exercise ( 35% V.O2max for 90 min) in a hot (43°C, 30% RH) environment for 8 days. The heat acclimation regimen increased performance time, lowered final rectal temperature (Tre) and percentage maximal heart rate (%HRmax), improved thermal comfort and decreased sweat sodium concentration similarly in all groups. Although total body sweating rates (M.sw) during acclimation were significantly greater in the Y and HO groups than in the NO group (Pgroup), the M.sw did not change in all groups with the acclimation sessions. Neither were local sweating rates (m.sw) on chest, back, forearm and thigh changed in all groups by the acclimation. The HO group presented greater forearm m.sw (30-90 min) values and the Y group had greater back and thigh m.sw (early in exercise) values, compared to the other groups (PHO>NO, and on the forearm Y=HO>NO. No group differences were observed for activated sweat gland density at any site. The SGO at the respective sites increased in the post-acclimation test regardless of group (Pgroups than in the Y group. These findings suggest that heat tolerance and the improvement with acclimation are little impaired not only in highly fit older but also normally fit older men, when the subjects exercised at the same relative exercise intensity. Furthermore, the changes induced by acclimation appear associated with an age-related decrease in V.O2max. However methylcholine-activated SGO and the magnitude of improvement of SGO with

  12. Extended analysis of retrodirective cross-eye jamming

    CSIR Research Space (South Africa)

    Du Plessis, WP

    2009-09-01

    Full Text Available certain conditions, a monopulse radar system can be more easily deceived than suggested by conventional cross-eye analyses. Furthermore, the cross-eye jammer antenna patterns do not affect the induced monopulse error....

  13. A Comparison of DDS and DRFM Techniques in the Generation of ’Smart Noise’ Jamming Waveforms.

    Science.gov (United States)

    1996-09-01

    either Direct Digital Synthesis (DDS) or Digital RF Memory ( DRFM ) based support jamming. The challenge lies in the fact the modern radar employs...thesis compares the effectiveness of using DDS versus DRFM techniques to meet this challenge. In particular, the effect of mismatched frequency on the...DDS jamming waveform is described, as is the effect of quantization and multi-signal storage in the DRFM . A quantitative comparison of these jamming techniques against the AN/TPS-70 surveillance radar is made.

  14. Welding of 3D-printed carbon nanotube-polymer composites by locally induced microwave heating.

    Science.gov (United States)

    Sweeney, Charles B; Lackey, Blake A; Pospisil, Martin J; Achee, Thomas C; Hicks, Victoria K; Moran, Aaron G; Teipel, Blake R; Saed, Mohammad A; Green, Micah J

    2017-06-01

    Additive manufacturing through material extrusion, often termed three-dimensional (3D) printing, is a burgeoning method for manufacturing thermoplastic components. However, a key obstacle facing 3D-printed plastic parts in engineering applications is the weak weld between successive filament traces, which often leads to delamination and mechanical failure. This is the chief obstacle to the use of thermoplastic additive manufacturing. We report a novel concept for welding 3D-printed thermoplastic interfaces using intense localized heating of carbon nanotubes (CNTs) by microwave irradiation. The microwave heating of the CNT-polymer composites is a function of CNT percolation, as shown through in situ infrared imaging and simulation. We apply CNT-loaded coatings to a 3D printer filament; after printing, microwave irradiation is shown to improve the weld fracture strength by 275%. These remarkable results open up entirely new design spaces for additive manufacturing and also yield new insight into the coupling between dielectric properties and radio frequency field response for nanomaterial networks.

  15. Quercetin suppresses heat shock-induced nuclear translocation of Hsp72

    Directory of Open Access Journals (Sweden)

    Antoni Gawron

    2011-08-01

    Full Text Available The effect of quercetin and heat shock on the Hsp72 level and distribution in HeLa cells was studied by Western blotting, indirect immunofluorescence and immunogold electron microscopy. In control cells and after quercetin treatment, Hsp72 was located both in the cytoplasm and in the nucleus in comparable amounts. After hyperthermia, the level of nuclear Hsp72 raised dramatically. Expression of Hsp72 in cytoplasm was also higher but not to such extent as that observed in the nucleus. Preincubation of heated cells with quercetin inhibited strong Hsp72 expression observed after hyperthermia and changed the intracellular Hsp72 distribution. The cytoplasmic level of protein exceeded the nuclear one, especially around the nucleus, where the coat of Hsp72 was noticed. Observations indicating that quercetin was present around and in the nuclear envelope suggested an involvement of this drug in the inhibition of nuclear translocation. Our results indicate that pro-apoptotic activity of quercetin may be correlated not only with the inhibition of Hsp72 expression but also with suppression of its migration to the nucleus.

  16. Tyrosine ameliorates heat induced delay in event related potential P300 and contingent negative variation.

    Science.gov (United States)

    Kishore, Krishna; Ray, Koushik; Anand, J P; Thakur, Lalan; Kumar, Sanjeev; Panjwani, Usha

    2013-12-01

    The efficacy of tyrosine, a catecholamine precursor, as a countermeasure in the reduction of cognitive decline during heat exposure (HE) using event-related potential P300, and contingent negative variation (CNV) was evaluated. Ten healthy males, age 20-30years participated in the study. Volunteers received placebo or tyrosine (6.5g) 90min prior to HE (1.5h in 45°C+30% RH). P300 latency was significantly increased (p<0.01) during exposure with placebo, which was reduced significantly (p<0.01) after tyrosine supplementation. There was an increase in CNV M100 latency (p<0.05) and reaction time (p<0.01) and decrease in M100 amplitude (p<0.01) during HE with placebo, which returns to near normal level with the tyrosine administration. A significantly higher plasma norepinephrine (p<0.05), dopamine and epinephrine levels were detected in tyrosine supplemented group post heat exposure. HE increases the brain catecholamine activity thereby reduces the plasma norepinephrine and dopamine level leading to a reduction in cognitive performances. Tyrosine supplementation increases the catecholamine level and reduces the impairment of cognitive performance during HE. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. Detecting Crop Functional Response to a Heat Wave using Airborne Reflectance and Sun-induced Chlorophyll Fluorescence Measurements

    Science.gov (United States)

    Yang, P.; Van der Tol, C.; Rascher, U.; Damm, A.; Schickling, A.; Verhoef, W.

    2016-12-01

    This study presents an analysis of airborne measured reflectance (R) and solar-induced chlorophyll fluorescence (SIF) as indicators of high temperature stress in agricultural crops. We used atmospherically corrected R and retrievals of SIF in the O2-A band as obtained from HyPlant data over C3 crops (rapeseed, wheat and barley) and a C4 crop (corn) in Germany before (30th June) and during (2nd July) a heat wave in 2015. The availability of airborne data during this heat wave allowed us to detect fluorescence emission efficiency changes as an indicator of crop photosynthetic performance in response to temperature fluctuations. We found that SIF is affected relatively stronger by heat stress than R. This is according to expectation, because the R spectrum is determined by leaf properties and canopy structure, whereas top-of-canopy (TOC) SIF is also affected by the temperature dependent efficiencies of photochemical and non-photochemical quenching of fluorescence. With the model 'Soil Canopy Observation of Photosynthesis and Energy fluxes (SCOPE), we differentiated leaf optical parameters and canopy structure from the fluorescence quantum emission efficiency (FQE), i.e. the ratio of fluorescence production to light absorption of photosystems. The leaf optical and canopy structure parameters were retrieved from R by inversion of the radiative transfer module 'RTMo' of SCOPE. The retrieved parameters were further used to estimate the FQE from SIF measurements. It appeared that both the leaf water content CW and the FQE responded to the heat wave, but the responses were different for C3 and C4 crops. A slight reduction of CW occurred in C3 crops between the two days, but not in the C4 crop. The reduction of FQE was only significant in C3 crops, and ranged from 18% to 31% for various C3 species. These findings agree with the general knowledge that C4 plants are better adapted to high temperature than C3 plants, and comply with simulations from a biochemical model for C3

  18. Nav1.9 channel contributes to mechanical and heat pain hypersensitivity induced by subacute and chronic inflammation.

    Directory of Open Access Journals (Sweden)

    Stéphane Lolignier

    Full Text Available Inflammation is known to be responsible for the sensitization of peripheral sensory neurons, leading to spontaneous pain and invalidating pain hypersensitivity. Given its role in regulating neuronal excitability, the voltage-gated Nav1.9 channel is a potential target for the treatment of pathological pain, but its implication in inflammatory pain is yet not fully described. In the present study, we examined the role of the Nav1.9 channel in acute, subacute and chronic inflammatory pain using Nav1.9-null mice and Nav1.9 knock-down rats. In mice we found that, although the Nav1.9 channel does not contribute to basal pain thresholds, it plays an important role in heat pain hypersensitivity induced by subacute paw inflammation (intraplantar carrageenan and chronic ankle inflammation (complete Freund's adjuvant-induced monoarthritis. We showed for the first time that Nav1.9 also contributes to mechanical hypersensitivity in both models, as assessed using von Frey and dynamic weight bearing tests. Consistently, antisense-based Nav1.9 gene silencing in rats reduced carrageenan-induced heat and mechanical pain hypersensitivity. While no changes in Nav1.9 mRNA levels were detected in dorsal root ganglia (DRGs during subacute and chronic inflammation, a significant increase in Nav1.9 immunoreactivity was observed in ipsilateral DRGs 24 hours following carrageenan injection. This was correlated with an increase in Nav1.9 immunolabeling in nerve fibers surrounding the inflamed area. No change in Nav1.9 current density could be detected in the soma of retrolabeled DRG neurons innervating inflamed tissues, suggesting that newly produced channels may be non-functional at this level and rather contribute to the observed increase in axonal transport. Our results provide evidence that Nav1.9 plays a crucial role in the generation of heat and mechanical pain hypersensitivity, both in subacute and chronic inflammatory pain models, and bring new elements for the

  19. Nav1.9 channel contributes to mechanical and heat pain hypersensitivity induced by subacute and chronic inflammation.

    Science.gov (United States)

    Lolignier, Stéphane; Amsalem, Muriel; Maingret, François; Padilla, Françoise; Gabriac, Mélanie; Chapuy, Eric; Eschalier, Alain; Delmas, Patrick; Busserolles, Jérôme

    2011-01-01

    Inflammation is known to be responsible for the sensitization of peripheral sensory neurons, leading to spontaneous pain and invalidating pain hypersensitivity. Given its role in regulating neuronal excitability, the voltage-gated Nav1.9 channel is a potential target for the treatment of pathological pain, but its implication in inflammatory pain is yet not fully described. In the present study, we examined the role of the Nav1.9 channel in acute, subacute and chronic inflammatory pain using Nav1.9-null mice and Nav1.9 knock-down rats. In mice we found that, although the Nav1.9 channel does not contribute to basal pain thresholds, it plays an important role in heat pain hypersensitivity induced by subacute paw inflammation (intraplantar carrageenan) and chronic ankle inflammation (complete Freund's adjuvant-induced monoarthritis). We showed for the first time that Nav1.9 also contributes to mechanical hypersensitivity in both models, as assessed using von Frey and dynamic weight bearing tests. Consistently, antisense-based Nav1.9 gene silencing in rats reduced carrageenan-induced heat and mechanical pain hypersensitivity. While no changes in Nav1.9 mRNA levels were detected in dorsal root ganglia (DRGs) during subacute and chronic inflammation, a significant increase in Nav1.9 immunoreactivity was observed in ipsilateral DRGs 24 hours following carrageenan injection. This was correlated with an increase in Nav1.9 immunolabeling in nerve fibers surrounding the inflamed area. No change in Nav1.9 current density could be detected in the soma of retrolabeled DRG neurons innervating inflamed tissues, suggesting that newly produced channels may be non-functional at this level and rather contribute to the observed increase in axonal transport. Our results provide evidence that Nav1.9 plays a crucial role in the generation of heat and mechanical pain hypersensitivity, both in subacute and chronic inflammatory pain models, and bring new elements for the understanding of its

  20. Proteins associated with heat-induced leaf senescence in creeping bentgrass as affected by foliar application of nitrogen, cytokinins, and an ethylene inhibitor.

    Science.gov (United States)

    Jespersen, David; Huang, Bingru

    2015-02-01

    Heat stress causes premature leaf senescence in cool-season grass species. The objective of this study was to identify proteins regulated by nitrogen, cytokinins, and ethylene inhibitor in relation to heat-induced leaf senescence in creeping bentgrass (Agrostis stolonifera). Plants (cv. Penncross) were foliar sprayed with 18 mM carbonyldiamide (N source), 25 μM aminoethoxyvinylglycine (AVG, ethylene inhibitor), 25 μM zeatin riboside (ZR, cytokinin), or a water control, and then exposed to 20/15°C (day/night) or 35/30°C (heat stress) in growth chambers. All treatments suppressed heat-induced leaf senescence, as shown by higher turf quality and chlorophyll content, and lower electrolyte leakage in treated plants compared to the untreated control. A total of 49 proteins were responsive to N, AVG, or ZR under heat stress. The abundance of proteins in photosynthesis increased, with ribulose-1,5-bisphosphate carboxylase/oxygenase affected by all three treatments, chlorophyll a/b-binding protein by AVG and N or Rubisco activase by AVG. Proteins for amino acid metabolism were upregulated, including alanine aminotransferase by three treatments and ferredoxin-dependent glutamate synthase by AVG and N. Upregulated proteins also included catalase by AVG and N and heat shock protein by ZR. Exogenous applications of AVG, ZR, or N downregulated proteins in respiration (enolase, glyceraldehyde 3-phosphate dehydrogenase, and succinate dehygrogenase) under heat stress. Alleviation of heat-induced senescence by N, AVG, or ZR was associated with enhanced protein abundance in photosynthesis and amino acid metabolism and stress defense systems (heat shock protection and antioxidants), as well as suppression of those imparting respiration metabolism. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Nitric oxide and heat shock protein 90 co-regulate temperature-induced bleaching in the soft coral Eunicea fusca

    Science.gov (United States)

    Ross, Cliff

    2014-06-01

    Coral bleaching represents a complex physiological process that is affected not only by environmental conditions but by the dynamic internal cellular biology of symbiotic dinoflagellates ( Symbiodinium spp.) and their cnidarian hosts. Recently, nitric oxide (NO) has emerged as a key molecule involved with the expulsion of Symbiodinium from host cnidarian cells. However, the site of production remains under debate, and the corresponding signaling pathways within and between host and endosymbiont remain elusive. In this study, using freshly isolated Symbiodinium from the soft coral Eunicea fusca, I demonstrate that thermally induced stress causes an upregulation in Symbiodinium heat shock protein 90 (Hsp90). In turn, Hsp90 shows a concomitant ability to enhance the activity of a constitutively expressed isoform of NO synthase. The resulting production of NO constitutes a signaling molecule capable of inducing Symbiodinium expulsion. Using nitric oxide synthase (NOS) and Hsp90 polyclonal antibodies, thermal stress-induced Hsp90 was shown to co-immunoprecipitate with a constitutive isoform of NOS. The specific blocking of Hsp90 activity, with the Hsp90 inhibitor geldanamycin, was capable of inhibiting NO production implicating the involvement of a coordinated regulatory system. These results have strong evolutionary implications for Hsp90-NOS chaperone complexes among biological kingdoms and provide evidence for a new functional role in symbiotic associations.

  2. Azetidine-induced accumulation of class I small heat shock proteins in the soluble fraction provides thermotolerance in soybean seedlings.

    Science.gov (United States)

    Jinn, Tsung-Luo; Chiu, Chi-Chou; Song, Wei-Wen; Chen, Yih-Ming; Lin, Chu-Yung

    2004-12-01

    Accumulation of class I small heat shock proteins (sHSPs) is induced by the proline analog, azetidine-2-carboxylic acid (Aze) in soybean seedlings to a level similar to that induced by exposure to 40 degrees C. However, only the treatment with 10 mM Aze for 6 h and subsequently with 10 mM proline for 24 h protected the seedlings from damage during subsequent exposure to 45 degrees C as assessed by 2,3,5-triphenyltetrazolium chloride (TTC) staining. A chaperone activity assay showed that the purified class I sHSPs induced by Aze were functional in vitro and protected proteins from thermal denaturation. Amino acid composition analysis indicated that Aze was not incorporated into de novo synthesized class I sHSPs. Accumulation of class I sHSPs in the soluble post-ribosomal supernatant fraction was found to be important for acquisition of thermotolerance. We suggest that both the accumulation of class I sHSPs and their presence in the soluble fraction are important for establishment of thermotolerance.

  3. Antisense oligonucleotide inhibition of Heat Shock Protein (HSP 47 improves bleomycin-induced pulmonary fibrosis in rats

    Directory of Open Access Journals (Sweden)

    Noguchi Takayuki

    2007-05-01

    Full Text Available Abstract Background The most common pathologic form of pulmonary fibrosis arises from excessive deposition of extracellular matrix proteins such as collagen. The 47 kDa heat shock protein 47 (HSP47 is a collagen-specific molecular chaperone that has been shown to play a major role during the processing and/or secretion of procollagen. Objectives To determine whether inhibition of HSP47 could have beneficial effects in mitigating bleomycin-induced pulmonary fibrosis in rats. Methods All experiments were performed with 250–300 g male Wistar rats. Animals were randomly divided into five experimental groups that were administered: 1 saline alone, 2 bleomycin alone, 3 antisense HSP47 oligonucleotides alone, 4 bleomycin + antisense HSP47 oligonucleotides, and 5 bleomycin + sense control oligonucleotides. We investigated lung histopathology and performed immunoblot and immunohistochemistry analyses. Results In rats treated with HSP47 antisense oligonucleotides, pulmonary fibrosis was significantly reduced. In addition, treatment with HSP47 antisense oligonucleotides significantly improved bleomycin-induced morphological changes. Treatment with HSP47 antisense oligonucleotides alone did not produce any significant changes to lung morphology. Immunoblot analyses of lung homogenates confirmed the inhibition of HSP47 protein by antisense oligonucleotides. The bleo + sense group, however, did not exhibit any improvement in lung pathology compared to bleomycin alone groups, and also had no effect on HSP47 expression. Conclusion These findings suggest that HSP47 antisense oligonucleotide inhibition of HSP47 improves bleomycin-induced pulmonary fibrosis pathology in rats.

  4. The current-induced heat generation in a spin-flip quantum dot sandwiched between a ferromagnetic and a superconducting electrode

    Science.gov (United States)

    Jiang, Feng; Yan, Yonghong; Wang, Shikuan; Yan, Yijing

    2017-12-01

    Using non-equilibrium Green's functions' theory based on extended Nambu representation and small polaron transformation, we studied the current-induced heat generation in a spin-flip quantum dot sandwiched between a ferromagnetic and a superconducting electrode. We focused on moderate dot-leads coupling and relative small phonon energy, and derived the detailed expression of heat generation. The numerical results show (i) the heat generation decreases with polarization degree increasing, (ii) the intradot spin-flip can have a great effect on the heat generation at both zero temperature and finite temperature and (iii) at finite temperature an optimal workspace of keeping spin current and tuning heat generation by modulating the spin-flip intensity can be found.

  5. Gibberellic Acid-Induced Aleurone Layers Responding to Heat Shock or Tunicamycin Provide Insight into the N-Glycoproteome, Protein Secretion, and Endoplasmic Reticulum Stress

    DEFF Research Database (Denmark)

    Barba Espin, Gregorio; Dedvisitsakul, Plaipol; Hägglund, Per

    2014-01-01

    respond to gibberellic acid by secreting an array of proteins and provide a unique system for the analysis of plant protein secretion. Perturbation of protein secretion in gibberellic acid-induced aleurone layers by two independent mechanisms, heat shock and tunicamycin treatment, demonstrated overlapping...... and secretion, such as calreticulin, protein disulfide isomerase, proteasome subunits, and isopentenyl diphosphate isomerase. Sixteen heat shock proteins in 29 spots showed diverse responses to the treatments, with only a minority increasing in response to heat shock. The majority, all of which were small heat...... shock proteins, decreased in heat-shocked aleurone layers. Additionally, glycopeptide enrichment and N-glycosylation analysis identified 73 glycosylation sites in 65 aleurone layer proteins, with 53 of the glycoproteins found in extracellular fractions and 36 found in intracellular fractions...

  6. Separating spin torque and heating effects in current-induced domain wall motion probed by high-resolution transmission electron microscopy

    DEFF Research Database (Denmark)

    Junginger, F.; Klaeui, M.; Backes, D.

    2007-01-01

    Observations of domain wall motion and transformations due to injected current pulses in permalloy zigzag structures using off-axis electron holography and Lorentz microscopy are reported. Heating on membranes leads to thermally activated random behavior at low current densities and by backcoating...... the SiN membranes with Al, heating effects are significantly reduced. A set of indicators is devised to separate unambiguously spin torque effects from heating and it is shown that by using the Al layer the structures are sufficiently cooled to exhibit current-induced domain wall motion due to spin...

  7. Enhanced heat loss responses induced by short-term endurance training in exercising women.

    Science.gov (United States)

    Ichinose, Tomoko K; Inoue, Yoshimitsu; Hirata, Mari; Shamsuddin, A K M; Kondo, Narihiko

    2009-01-01

    We investigated the effects of short-term endurance training and detraining on sweating and cutaneous vasodilatation during exercise in young women, taking into account changes in maximal oxygen uptake (VO2max) and the phase of the menstrual cycle. Eleven untrained women participated in endurance training; cycle exercise at approximately 60% VO2max for 60 min day(-1), 4-5 days week(-1) (30 degrees C, 45% relative humidity) for three complete menstrual cycles. The standard exercise test consisted of exercise at 50% VO2max for 30 min (25 degrees C, 45% relative humidity), and was conducted before training (Pre), during training sessions (T1, T2 and T3) and after cessation of training (D1 and D2). Values of VO2max increased significantly from 32.7 +/- 1.2 to 37.8 +/- 1.2 ml min(-1) kg(-1) at the end of the training. Local sweat rate in the chest and thigh, but not in the back and forearm, were significantly greater during T1 and T2 only in women who started training from the midfollicular phase. Cutaneous blood flow did not change with training. The threshold oesophageal temperatures for heat loss responses were significantly decreased during T1 versus Pre (averaged values for each body site: sweating, 37.49 +/- 0.08 versus 37.22 +/- 0.12 degrees C; and cutaneous vasodilatation, 37.40 +/- 0.07 versus 37.17 +/- 0.10 degrees C) and maintained through T3; the sensitivities of heat loss responses were not altered. These changes returned to the Pre level by D1. Our data indicate that physical training improves heat loss responses by decreasing the threshold temperatures and that these effects occur within a month of training and disappear within a month after cessation of training. The degree of increase in sweating with training differs among body sites and might be affected by the phase of the menstrual cycle.

  8. Heat hyperalgesia and mechanical hypersensitivity induced by calcitonin gene-related peptide in a mouse model of neurofibromatosis.

    Directory of Open Access Journals (Sweden)

    Stephanie White

    Full Text Available This study examined whether mice with a deficiency of neurofibromin, a Ras GTPase activating protein, exhibit a nociceptive phenotype and probed a possible contribution by calcitonin gene-related peptide. In the absence of inflammation, Nf1+/- mice (B6.129S6 Nf1/J and wild type littermates responded comparably to heat or mechanical stimuli, except for a subtle enhanced mechanical sensitivity in female Nf1+/- mice. Nociceptive phenotype was also examined after inflammation induced by capsaicin and formalin, which release endogenous calcitonin gene-related peptide. Intraplantar injection of capsaicin evoked comparable heat hyperalgesia and mechanical hypersensitivity in Nf1+/- and wild type mice of both genders. Formalin injection caused a similar duration of licking in male Nf1+/- and wild type mice. Female Nf1+/- mice licked less than wild type mice, but displayed other nociceptive behaviors. In contrast, intraplantar injection of CGRP caused greater heat hyperalgesia in Nf1+/- mice of both genders compared to wild type mice. Male Nf1+/- mice also exhibited greater mechanical hypersensitivity; however, female Nf1+/- mice exhibited less mechanical hypersensitivity than their wild type littermates. Transcripts for calcitonin gene-related peptide were similar in the dorsal root ganglia of both genotypes and genders. Transcripts for receptor activity-modifying protein-1, which is rate-limiting for the calcitonin gene-related peptide receptor, in the spinal cord were comparable for both genotypes and genders. The increased responsiveness to intraplantar calcitonin gene-related peptide suggests that the peripheral actions of calcitonin gene-related peptide are enhanced as a result of the neurofibromin deficit. The analgesic efficacy of calcitonin gene-related peptide receptor antagonists may therefore merit investigation in neurofibromatosis patients.

  9. Heat hyperalgesia and mechanical hypersensitivity induced by calcitonin gene-related peptide in a mouse model of neurofibromatosis.

    Science.gov (United States)

    White, Stephanie; Marquez de Prado, Blanca; Russo, Andrew F; Hammond, Donna L

    2014-01-01

    This study examined whether mice with a deficiency of neurofibromin, a Ras GTPase activating protein, exhibit a nociceptive phenotype and probed a possible contribution by calcitonin gene-related peptide. In the absence of inflammation, Nf1+/- mice (B6.129S6 Nf1/J) and wild type littermates responded comparably to heat or mechanical stimuli, except for a subtle enhanced mechanical sensitivity in female Nf1+/- mice. Nociceptive phenotype was also examined after inflammation induced by capsaicin and formalin, which release endogenous calcitonin gene-related peptide. Intraplantar injection of capsaicin evoked comparable heat hyperalgesia and mechanical hypersensitivity in Nf1+/- and wild type mice of both genders. Formalin injection caused a similar duration of licking in male Nf1+/- and wild type mice. Female Nf1+/- mice licked less than wild type mice, but displayed other nociceptive behaviors. In contrast, intraplantar injection of CGRP caused greater heat hyperalgesia in Nf1+/- mice of both genders compared to wild type mice. Male Nf1+/- mice also exhibited greater mechanical hypersensitivity; however, female Nf1+/- mice exhibited less mechanical hypersensitivity than their wild type littermates. Transcripts for calcitonin gene-related peptide were similar in the dorsal root ganglia of both genotypes and genders. Transcripts for receptor activity-modifying protein-1, which is rate-limiting for the calcitonin gene-related peptide receptor, in the spinal cord were comparable for both genotypes and genders. The increased responsiveness to intraplantar calcitonin gene-related peptide suggests that the peripheral actions of calcitonin gene-related peptide are enhanced as a result of the neurofibromin deficit. The analgesic efficacy of calcitonin gene-related peptide receptor antagonists may therefore merit investigation in neurofibromatosis patients.

  10. Role of the carbohydrate chain and two phosphate moieties in the heat-induced aggregation of hen ovalbumin.

    Science.gov (United States)

    Tani, Fumito; Shirai, Nobuaki; Nakanishi, Yukiko; Yasumoto, Kyoden; Kitabatake, Naofumi

    2004-12-01

    We investigated the effect of the carbohydrate chain and two phosphate moieties on heat-induced aggregation of hen ovalbumin. The dephosphorylated form of ovalbumin was obtained by treating the original protein with acid phosphatase. The single carbohydrate chain was removed by digestion of heat-denatured ovalbumin with glycopeptidase F, and the resulting polypeptide without this carbohydrate chain was correctly refolded to acquire protease-resistance. Thermal unfolding can be approximated by a mechanism involving a two-state transition between the folded and unfolded states with a midpoint temperature of 76 degrees C for the original form, of 74 degrees C for the dephosphorylated form, and of 71 degrees C for the carbohydrate-free form. The conformational stability of the original form was higher than that of the carbohydrate-free form. When the three forms of ovalbumin were heated to 80 degrees C and then cooled rapidly in an ice bath, the polypeptide chains were compactly collapsed to metastable intermediates with secondary structures whose properties were indistinguishable. Upon incubation at 60 degrees C, renaturation was possible for a large portion of the intermediates of the original form, but for only a small portion of those of the carbohydrate-free form. Light scattering experiments showed that in the presence of sulfate anions, the intermediates of the carbohydrate-free form aggregated to a greater extent than did those of the original form. The intermediates of the carbohydrate-free form bound to the chaperonin GroEL with about 10-fold higher affinity than those of the original form. It follows that the carbohydrate chain and the two phosphate moieties do not affect hydrophobic collapse in the kinetic refolding of hen ovalbumin but play an important role in the slow rearrangement. They block the off-pathway reaction that competes with correct refolding by effectively decreasing surface hydrophobicity.

  11. Alkylation-, Heating-, and Doping-Induced Emission Enhancement of a Polyaromatic Tube in the Solid State.

    Science.gov (United States)

    Kuroda, Kiyonori; Otsuki, Masafumi; Yazaki, Kohei; Sei, Yoshihisa; Akita, Munetaka; Yoshizawa, Michito

    2018-01-11

    A polyaromatic tube with a subnanometer-sized cavity was efficiently prepared on a gram-scale through the stereo-controlled cyclotrimerization of a diphenylanthracene derivative as a key step. The facile exterior alkylation of the polyaromatic framework leads to a moderately fluorescent tube (R = -OC10H21; ΦF = 20%) in the solid state. The emission intensity of the solid-state alkyl-substituted tube is remarkably enhanced upon heating (up to 1.6 times, ΦF = 31%) as well as doping with fluorescent dyes (up to 4.2 times, ΦF = 83%) through efficient energy transfer. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Effect of temperature on rectified diffusion during ultrasound-induced heating.

    Science.gov (United States)

    Webb, Ian R; Payne, Stephen J; Coussios, Constantin-C

    2011-11-01

    Experimental observations of delayed-onset cavitation during ultrasound insonation have been suggested as being caused by a change in the size distribution of the bubble population due to rectified diffusion. To investigate this hypothesis, a single bubble model is used here to explore the effect of heating and the subsequent elevated temperatures on the rectified diffusion process. Numerical solution of the model, which includes the temperature dependences of seven relevant physical parameters, allows quantification of the change in the pressure threshold for rectified diffusion, as well as the importance of the bulk liquid saturation concentration in determining bubble evolution. Although elevated temperatures and liquid supersaturation reduce the rectified diffusion threshold, it remains coincident with the inertial cavitation thresholds at submicron bubble sizes at all temperatures. This observation suggests that changes in the nucleation environment, rather than bubble growth due to rectified diffusion, is a more likely cause of delayed-onset cavitation events.

  13. Experimental study on cross-flow induced vibrations in heat exchanger tube bundle

    Science.gov (United States)

    Khushnood, Shahab; Nizam, Luqman Ahmad

    2017-03-01

    Vibration in heat exchangers is one of the main problems that the industry has faced over last few decades. Vibration phenomenon in heat exchangers is of major concern for designers and process engineers since it can lead to the tube damage, tube leakage, baffle damage, tube collision damage, fatigue, creep etc. In the present study, vibration response is analyzed on single tube located in the centre of the tube bundle having parallel triangular arrangement (60°) with P/ D ratio of 1.44. The experiment is performed for two different flow conditions. This kind of experiment has not been reported in the literature. Under the first condition, the tube vibration response is analyzed when there is no internal flow in the tube and under the second condition, the response is analyzed when the internal tube flow is maintained at a constant value of 0.1 m/s. The free stream shell side velocity ranges from 0.8 m/s to 1.3 m/s, the reduced gap velocity varies from 1.80 to 2.66 and the Reynolds number varies from 44500 to 66000. It is observed that the internal tube flow results in larger vibration amplitudes for the tube than that without internal tube flow. It is also established that over the current range of shell side flow velocity, the turbulence is the dominant excitation mechanism for producing vibration in the tube since the amplitude varies directly with the increase in the shell side velocity. Damping has no significant effect on the vibration behavior of the tube for the current velocity range.

  14. Novel X-ray phase-contrast tomography method for quantitative studies of heat induced structural changes in meat

    DEFF Research Database (Denmark)

    Miklos, Rikke; Nielsen, Mikkel Schou; Einarsdottir, Hildur

    2014-01-01

    The objective of this study was to evaluate the use of X-ray phase-contrast tomography combined with 3D image segmentation to investigate the heat induced structural changes in meat. The measurements were performed at the Swiss synchrotron radiation light source using a grating interferometric...... and separated into a water phase and a gel phase formed by the sarcoplasmic proteins in the exudate. The results show that X-ray phase contrast tomography offers unique possibilities in studies both the meat structure and the different meat component such as water, fat, connective tissue and myofibrils...... in a qualitative and quantitative manner without prior sample preparation as isolation of single muscle components, calibration or histology....

  15. MATERIALS THAT SHRINK ON HEATING: PRESSURE-INDUCED PHASE TRANSITIONS IN NEGATIVE THERMAL EXPANSION MATERIALS, AND THEIR ENERGETICS

    Energy Technology Data Exchange (ETDEWEB)

    Varga, Tamas

    2011-09-01

    Despite the fact that all chemical bonds expand on heating, a small class of materials shrinks when heated. These, so called negative thermal expansion (NTE) materials, are a unique class of materials with some exotic properties. The present chapter offers insight into the structural aspects of pressure- (or temperature-) induced phase transformations, and the energetics of those changes in these fascinating materials, in particular NTE compound cubic ZrW2O8, orthorhombic Sc2W3O12 and Sc2Mo3O12, as well as other members of the 'scandium tungstate family'. In subsequent sections, (i) combined in situ high-pressure synchrotron XRD and XAS studies of NTE material ZrW2O8; (ii) an in situ high-pressure synchrotron XRD study of Sc2W3O12, Sc2Mo3O12, and Al2W3O12; and (iii) thermochemical studies of the above materials are presented and discussed. In all of these studies, chemical bonds change, sometimes break and new ones form. Correlations between structure, chemistry, and energetics are revealed. It is also shown that (iv) NTE materials are good candidates as precursors to make novel solid state materials, such as the conducting Sc0.67WO4, using high-pressure, high-temperature synthesis, through modification of bonding and electronic structure, and thus provide vast opportunities for scientific exploration.

  16. Effects of particle size and laser-induced heating on the Raman spectra of alpha quartz grains.

    Science.gov (United States)

    Chio, Chi Hong; Sharma, Shiv K; Lucey, Paul G; Muenow, David W

    2003-07-01

    Raman spectra of alpha-quartz (Qz) grains of various size (250 microm to Raman and micro-Raman systems. Frequency downshift and line broadening of the 464 cm(-1), v,(Si-O-Si) band are observed in the smallest size group (Raman lines is also used to estimate the vibrational temperature of the samples under different excitation power. The degree of laser-induced heating is more noticeable in the aggregates than in the individual grains with the use of medium-level laser excitation (< or = 150 mW). Heating diminishes with increasing grain size, and it can only be detected in grain aggregates between 11 and 20 microm in diameter using 150 mW excitation. Intensity studies of the v(s)(Si-O-Si) band using individual grains show no noticeable signs of grain size effects. However, grain size effects become an important factor in the study of aggregates in which spectral intensity diminishes with respect to decreasing grain size.

  17. Fabrication of Hollow Silica Microspheres with Orderly Hemispherical Protrusions and Capability for Heat-Induced Controlled Cracking.

    Science.gov (United States)

    Takafuji, Makoto; Hano, Nanami; Alam, Md A; Ihara, Hirotaka

    2017-10-10

    Hollow silica microspheres with orderly protrusions on their outer and inner surfaces were fabricated in three simple steps: (1) suspension polymerization of a polymerizable monomer containing silica nanoparticles to obtain polymeric microspheres with a layered shell of silica particles; (2) sol-gel reaction of tetraethoxysilane (TEOS) on the surface of the microspheres to connect the silica nanoparticles; (3) removal of polymer core by calcination. The shell composed of silica-connected silica nanoparticles remained spherical even after calcination, and the characteristic surface morphology with protrusions were obtained on both inner and outer surfaces. Measurements of the mechanical strength revealed that the compression modulus of the hollow microspheres increased with increasing thickness of the silica layer, which could be controlled by changing the concentration of TEOS in the sol-gel reaction. Rapid heating of the hollow silica microspheres with the thin silica-connected layer led to silica shell cracking, and the cracks were mostly observed in the connecting layer between the silica nanoparticles. The stress was probably concentrated in the connecting layer because of its lower thickness than the nanoparticles. Such characteristic of the hollow microspheres is useful for a capsule with capability for heat-induced controlled cracking caused by internal pressure changes.

  18. Protective Effects of Salidroside on Mitochondrial Functions against Exertional Heat Stroke-Induced Organ Damage in the Rat

    Directory of Open Access Journals (Sweden)

    Wei Zhang

    2015-01-01

    Full Text Available Exertional heat stroke (EHS results in a constellation of systemic inflammatory responses resulting in multiorgan failure and an extremely high mortality. The present study was designed to evaluate the protective effects of salidroside on EHS by improving mitochondrial functions in the rat model. Liver and heart mitochondria were observed by transmission electron microscopy and mitochondrial membrane potential (ΔΨm was detected by a fluorescent probe. Intramitochondrial free Ca2+ concentration, mitochondrial respiratory control ratio (RCR, reactive oxygen species (ROS levels, superoxide dismutase (SOD, and malondialdehyde (MDA activity were detected by the corresponding kits. RT-PCR was performed to estimate peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α and manganese form of SOD (MnSOD mRNA expression. The results demonstrated that salidroside was able to relieve EHS damage by reducing the swelling of mitochondria, ROS levels, and MDA activity, as well as increasing ΔΨm, RCR, free Ca2+ concentration, SOD, PGC-1α, and MnSOD mRNA levels. In conclusion, salidroside has protective effects on mitochondrial functions against exertional heat stroke-induced organ damage in the rat.

  19. Warm preconditioning protects against acute heat-induced respiratory dysfunction and delays bleaching in a symbiotic sea anemone.

    Science.gov (United States)

    Hawkins, Thomas D; Warner, Mark E

    2017-03-15

    Preconditioning to non-stressful warming can protect some symbiotic cnidarians against the high temperature-induced collapse of their mutualistic endosymbiosis with photosynthetic dinoflagellates (Symbiodinium spp.), a process known as bleaching. Here, we sought to determine whether such preconditioning is underpinned by differential regulation of aerobic respiration. We quantified in vivo metabolism and mitochondrial respiratory enzyme activity in the naturally symbiotic sea anemone Exaiptasia pallida preconditioned to 30°C for >7 weeks as well as anemones kept at 26°C. Preconditioning resulted in increased Symbiodinium photosynthetic activity and holobiont (host+symbiont) respiration rates. Biomass-normalised activities of host respiratory enzymes [citrate synthase and the mitochondrial electron transport chain (mETC) complexes I and IV] were higher in preconditioned animals, suggesting that increased holobiont respiration may have been due to host mitochondrial biogenesis and/or enlargement. Subsequent acute heating of preconditioned and 'thermally naive' animals to 33°C induced dramatic increases in host mETC complex I and Symbiodinium mETC complex II activities only in thermally naive E. pallida These changes were not reflected in the activities of other respiratory enzymes. Furthermore, bleaching in preconditioned E. pallida (defined as the significant loss of symbionts) was delayed by several days relative to the thermally naive group. These findings suggest that changes to mitochondrial biogenesis and/or function in symbiotic cnidarians during warm preconditioning might play a protective role during periods of exposure to stressful heating. © 2017. Published by The Company of Biologists Ltd.

  20. Implementation of a practical model for light and heat distribution using laser-induced thermotherapy near to a large vessel

    Energy Technology Data Exchange (ETDEWEB)

    Verhey, J F [Department of Medical Informatics, University of Goettingen, Robert-Koch-Str. 40, D-37075 Goettingen (Germany); Mohammed, Y [Department of Medical Informatics, University of Goettingen, Robert-Koch-Str. 40, D-37075 Goettingen (Germany); Ludwig, A [Department of Craneo-Maxillofacial Surgery, University of Goettingen, Robert-Koch-Str. 40, D-37075 Goettingen (Germany); Giese, K [Department of Medical Informatics, University of Goettingen, Robert-Koch-Str. 40, D-37075 Goettingen (Germany)

    2003-11-07

    This paper introduces a simulation model for light and heat transport in tissues including perfusion effects. The model enables an efficient simulation of the damaged zone induced with an optical fibre for laser interstitial thermotherapy (LITT). It is designed specially for, but not limited to, tissue ablation in the neck region near to vessels. We describe in detail the effects of the rise in temperature caused by the absorption of light in tissue, using the heat equation and including the cooling effects of flow in vessels and of microperfusion in tissue in order to determine the extent of thermal damage. The extent of the necrosis zone is calculated with a damage function at each point of a finite element method (FEM) mesh. The FEM mesh is implemented with FEMLAB 2.3 as an add-on for finite element modelling for Matlab 6.5. LITT for tumour ablation in liver and some other anatomical regions is a well-known and established method (Bundesaerztekammer und Kassenaerztliche Bundesvereinigung 2002 Assessment der Bundesaerztekammer und der Kassenaerztlichen Bundesvereinigung, Koeln). Investigations of treatments using LITT in the neck region are still in progress. We propose a refined model to validate the LITT method in the future in another anatomic region, e.g., in the highly sensitive region of the neck. Our calculations show that in order to induce a lesion with a maximum diameter of about 1 cm near to a large vessel, an application time between 3 and 4 min is needed using a laser power of about 10 W with a Nd:YAG 1064 nm radiation wavelength.

  1. The heat-shock response co-inducer arimoclomol protects against retinal degeneration in rhodopsin retinitis pigmentosa.

    Science.gov (United States)

    Parfitt, D A; Aguila, M; McCulley, C H; Bevilacqua, D; Mendes, H F; Athanasiou, D; Novoselov, S S; Kanuga, N; Munro, P M; Coffey, P J; Kalmar, B; Greensmith, L; Cheetham, M E

    2014-05-22

    Retinitis pigmentosa (RP) is a group of inherited diseases that cause blindness due to the progressive death of rod and cone photoreceptors in the retina. There are currently no effective treatments for RP. Inherited mutations in rhodopsin, the light-sensing protein of rod photoreceptor cells, are the most common cause of autosomal-dominant RP. The majority of mutations in rhodopsin, including the common P23H substitution, lead to protein misfolding, which is a feature in many neurodegenerative disorders. Previous studies have shown that upregulating molecular chaperone expression can delay disease progression in models of neurodegeneration. Here, we have explored the potential of the heat-shock protein co-inducer arimoclomol to ameliorate rhodopsin RP. In a cell model of P23H rod opsin RP, arimoclomol reduced P23H rod opsin aggregation and improved viability of mutant rhodopsin-expressing cells. In P23H rhodopsin transgenic rat models, pharmacological potentiation of the stress response with arimoclomol improved electroretinogram responses and prolonged photoreceptor survival, as assessed by measuring outer nuclear layer thickness in the retina. Furthermore, treated animal retinae showed improved photoreceptor outer segment structure and reduced rhodopsin aggregation compared with vehicle-treated controls. The heat-shock response (HSR) was activated in P23H retinae, and this was enhanced with arimoclomol treatment. Furthermore, the unfolded protein response (UPR), which is induced in P23H transgenic rats, was also enhanced in the retinae of arimoclomol-treated animals, suggesting that arimoclomol can potentiate the UPR as well as the HSR. These data suggest that pharmacological enhancement of cellular stress responses may be a potential treatment for rhodopsin RP and that arimoclomol could benefit diseases where ER stress is a factor.

  2. Implementation of a practical model for light and heat distribution using laser-induced thermotherapy near to a large vessel

    Science.gov (United States)

    Verhey, J. F.; Mohammed, Y.; Ludwig, A.; Giese, K.

    2003-11-01

    This paper introduces a simulation model for light and heat transport in tissues including perfusion effects. The model enables an efficient simulation of the damaged zone induced with an optical fibre for laser interstitial thermotherapy (LITT). It is designed specially for, but not limited to, tissue ablation in the neck region near to vessels. We describe in detail the effects of the rise in temperature caused by the absorption of light in tissue, using the heat equation and including the cooling effects of flow in vessels and of microperfusion in tissue in order to determine the extent of thermal damage. The extent of the necrosis zone is calculated with a damage function at each point of a finite element method (FEM) mesh. The FEM mesh is implemented with FEMLAB 2.3 as an add-on for finite element modelling for Matlab 6.5. LITT for tumour ablation in liver and some other anatomical regions is a well-known and established method (Bundesärztekammer und Kassenärztliche Bundesvereinigung 2002 Assessment der Bundesärztekammer und der Kassenärztlichen Bundesvereinigung, Köln). Investigations of treatments using LITT in the neck region are still in progress. We propose a refined model to validate the LITT method in the future in another anatomic region, e.g., in the highly sensitive region of the neck. Our calculations show that in order to induce a lesion with a maximum diameter of about 1 cm near to a large vessel, an application time between 3 and 4 min is needed using a laser power of about 10 W with a Nd:YAG 1064 nm radiation wavelength.

  3. Early changes in microbial colonization selectively modulate intestinal enzymes, but not inducible heat shock proteins in young adult Swine.

    Directory of Open Access Journals (Sweden)

    Marie-Edith Arnal

    Full Text Available Metabolic diseases and obesity are developing worldwide in a context of plethoric intake of high energy diets. The intestine may play a pivotal role due to diet-induced alterations in microbiota composition and increased permeability to bacterial lipopolysaccharide inducing metabolic inflammation. Early programming of metabolic disorders appearing in later life is also suspected, but data on the intestine are lacking. Therefore, we hypothesized that early disturbances in microbial colonization have short- and long-lasting consequences on selected intestinal components including key digestive enzymes and protective inducible heat shock proteins (HSP. The hypothesis was tested in swine offspring born to control mothers (n = 12 or mothers treated with the antibiotic amoxicillin around parturition (n = 11, and slaughtered serially at 14, 28 and 42 days of age to assess short-term effects. To evaluate long-term consequences, young adult offspring from the same litters were offered a normal or a fat-enriched diet for 4 weeks between 140 and 169 days of age and were then slaughtered. Amoxicillin treatment transiently modified both mother and offspring microbiota. This was associated with early but transient reduction in ileal alkaline phosphatase, HSP70 (but not HSP27 and crypt depth, suggesting a milder or delayed intestinal response to bacteria in offspring born to antibiotic-treated mothers. More importantly, we disclosed long-term consequences of this treatment on jejunal alkaline phosphatase (reduced and jejunal and ileal dipeptidylpeptidase IV (increased and decreased, respectively of offspring born to antibiotic-treated dams. Significant interactions between early antibiotic treatment and later diet were observed for jejunal alkaline phosphatase and sucrase. By contrast, inducible HSPs were not affected. In conclusion, our data suggest that early changes in bacterial colonization not only modulate intestinal architecture and function transiently

  4. Aircraft Loss-of-Control Accident Prevention: Switching Control of the GTM Aircraft with Elevator Jam Failures

    Science.gov (United States)

    Chang, Bor-Chin; Kwatny, Harry G.; Belcastro, Christine; Belcastro, Celeste

    2008-01-01

    Switching control, servomechanism, and H2 control theory are used to provide a practical and easy-to-implement solution for the actuator jam problem. A jammed actuator not only causes a reduction of control authority, but also creates a persistent disturbance with uncertain amplitude. The longitudinal dynamics model of the NASA GTM UAV is employed to demonstrate that a single fixed reconfigured controller design based on the proposed approach is capable of accommodating an elevator jam failure with arbitrary jam position as long as the thrust control has enough control authority. This paper is a first step towards solving a more comprehensive in-flight loss-of-control accident prevention problem that involves multiple actuator failures, structure damages, unanticipated faults, and nonlinear upset regime recovery, etc.

  5. The heat-inducible essential response regulator WalR positively regulates transcription of sigI, mreBH and lytE in Bacillus subtilis under heat stress.

    Science.gov (United States)

    Huang, Wan-Zhen; Wang, Jyun-Jhih; Chen, Hui-Ju; Chen, Jung-Tze; Shaw, Gwo-Chyuan

    2013-12-01

    The actin homolog MreBH governs cell morphogenesis of Bacillus subtilis through localization of the cell wall hydrolase LytE. The alternative sigma factor SigI of B. subtilis coordinately regulates transcription of mreBH and lytE. Transcription of sigI, mreBH and lytE is heat-inducible. The essential response regulator WalR (YycF) plays a key role in coordinating cell wall metabolism with cell proliferation. We now demonstrate that mreBH is a new member of the WalR regulon. We also found that WalR can positively and directly regulate sigI transcription under heat stress through a binding site located upstream of the σ(I) promoter of sigI. In addition, we found that a WalR binding site located upstream of the SigI binding site in the regulatory region of lytE is important for lytE expression under heat stress. Moreover, we found that walR is a new member of the heat shock stimulon of B. subtilis. WalR appears to coordinately and positively regulate transcription of sigI, mreBH and lytE under heat stress. Finally, our work shows for the first time that WalR can stimulate activities of σ(I) promoters under heat stress. Copyright © 2013 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  6. Application of Photothermal Methods for Quantification of Carotenoids in Apricot Jams

    Science.gov (United States)

    Dóka, O.; Bicanic, D.; Stéger-Máté, M.; Végvári, Gy.

    2015-09-01

    Carotenes, found in a diversity of fruit-containing foods, are important sources of antioxidants; a good example is apricot jam. In the study described in this paper, both the total carotenoid content ( TCC) as well as the content of \\upbeta -carotene in six different apricot jams were quantified using traditional (UV-VIS) spectrophotometry (SP), high-performance liquid chromatography (HPLC), laser photoacoustic spectroscopy (LPAS), and the optothermal window (OW) method. Unlike SP and HPLC, LPAS and the OW methods require the minimum of sample preparation and only a one time calibration step which enables practically direct quantification of the TCC. Results were verified versus data obtained with SP as the reference technique. It was shown that LPAS and the OW method (at 473 nm) provide satisfactory results with R2=0.9884 and 0.9766 for LPAS and OW, respectively.

  7. Atlantoaxial joint jamming as a treatment for atlantoaxial dislocation: a preliminary report. Technical note.

    Science.gov (United States)

    Goel, Atul

    2007-07-01

    In this report the author describes an alternative technique of atlantoaxial fixation that involves blocking or "jamming" of movements of the atlantoaxial joint. The technique involves forcible impaction of spiked titanium metal spacers and bone grafts within the distracted atlantoaxial facet joints. Between January 2003 and January 2006, four patients underwent this method of fixation at the Department of Neurosurgery at King Edward Memorial Hospital in Mumbai, India. All four patients had posttraumatic mobile and reducible atlantoaxial dislocation. The mean follow-up period was 16 months (range 5-35 months). Successful atlantoaxial stabilization along with ultimate bone fusion was achieved in all patients and was documented on dynamic radiographs. There were no neurological, vascular, or infection-associated complications. The author concludes that the described method of atlantoaxial fixation provides an alternative treatment strategy. "Joint jamming" as a stand-alone method or in combination with other fixation methods may provide firm stabilization in cases of atlantoaxial dislocation.

  8. Beam Induced Ferrite Heating of the LHC Injection Kickers and Proposals for Improved Cooling

    CERN Document Server

    Barnes, M J; Calatroni, S; Day, H; Ducimetière, L; Garlaschè, M; Gomes Namora, V; Mertens, V; Sobiech, Z; Taborelli, M; Uythoven, J; Weterings, W

    2013-01-01

    The two LHC injection kicker systems produce an integrated field strength of 1.3 T·m with a flattop duration variable up to 7860 ns, and rise and fall times of less than 900 ns and 3000 ns, respectively. A beam screen is placed in the aperture of each magnet, which consists of a ceramic tube with conductors in the inner wall. The conductors provide a path for the beam image current and screen the ferrite yoke against wakefields. Recent LHC operation, with high intensity beam stable for many hours, resulted in significant heating of both the ferrite yoke and beam impedance reduction ferrites. For one kicker magnet the ferrite yoke approached its Curie temperature. As a result of a long thermal time-constant the ferrite yoke can require several hours to cool sufficiently to allow re-injection of beam, thus limiting the running efficiency of the LHC. Thermal measurement data has been analysed, a thermal model developed and emissivity measurements carried out. Various measures to improve the ferrite cooling have...

  9. Structural, physical, and chemical modifications induced by microwave heating on native agar-like galactans.

    Science.gov (United States)

    Sousa, Ana M M; Morais, Simone; Abreu, Maria H; Pereira, Rui; Sousa-Pinto, Isabel; Cabrita, Eurico J; Delerue-Matos, Cristina; Gonçalves, Maria Pilar

    2012-05-16

    Native agars from Gracilaria vermiculophylla produced in sustainable aquaculture systems (IMTA) were extracted under conventional (TWE) and microwave (MAE) heating. The optimal extracts from both processes were compared in terms of their properties. The agars' structure was further investigated through Fourier transform infrared and NMR spectroscopy. Both samples showed a regular structure with an identical backbone, β-d-galactose (G) and 3,6-anhydro-α-l-galactose (LA) units; a considerable degree of methylation was found at C6 of the G units and, to a lesser extent, at C2 of the LA residues. The methylation degree in the G units was lower for MAE(opt) agar; the sulfate content was also reduced. MAE led to higher agar recoveries with drastic extraction time and solvent volume reductions. Two times lower values of [η] and M(v) obtained for the MAE(opt) sample indicate substantial depolymerization of the polysaccharide backbone; this was reflected in its gelling properties; yet it was clearly appropriate for commercial application in soft-texture food products.

  10. Monitoring heat-induced changes in soft tissues with 1D transient elastography

    Energy Technology Data Exchange (ETDEWEB)

    Benech, Nicolas; Negreira, Carlos A [Laboratorio de Acustica Ultrasonora, Facultad de Ciencias, Igua 4225, 11400, Montevideo (Uruguay)

    2010-03-21

    In this paper 1D transient elastography was employed in fresh bovine skeletal muscle samples to assess the shear elastic modulus {mu} while the tissue was locally heated by means of an electrical resistance. The investigation is based on the study of the time shift of the shear wave propagation produced by the local temperature variation. The experiments show that the thermal expansion contribution to the time shift is negligible when compared with the shear wave speed variation. In such a case, the quantification of {mu} as a function of temperature becomes possible. Repeated experiments in different samples lead to a reproducible behavior of {mu} as a function of temperature. Irreversible elasticity changes are produced when the temperature exceeds a certain critical value T{sub c}. The proposed method allows estimating this value as well as the spatial extension of the resulting thermal lesion. This point is important when considering applications in monitoring focused ultrasound surgery (FUS) because the surrounding normal tissue should remain unaffected.

  11. A computational study of droplet evaporation with fuel vapor jet ejection induced by localized heat sources

    KAUST Repository

    Sim, Jaeheon

    2015-05-12

    Droplet evaporation by a localized heat source under microgravity conditions was numerically investigated in an attempt to understand the mechanism of the fuel vapor jet ejection, which was observed experimentally during the flame spread through a droplet array. An Eulerian-Lagrangian method was implemented with a temperature-dependent surface tension model and a local phase change model in order to effectively capture the interfacial dynamics between liquid droplet and surrounding air. It was found that the surface tension gradient caused by the temperature variation within the droplet creates a thermo-capillary effect, known as the Marangoni effect, creating an internal flow circulation and outer shear flow which drives the fuel vapor into a tail jet. A parametric study demonstrated that the Marangoni effect is indeed significant at realistic droplet combustion conditions, resulting in a higher evaporation constant. A modified Marangoni number was derived in order to represent the surface force characteristics. The results at different pressure conditions indicated that the nonmonotonic response of the evaporation rate to pressure may also be attributed to the Marangoni effect.

  12. Predictive response surface model for heat-induced rheological changes and aggregation of whey protein concentrate.

    Science.gov (United States)

    Alvarez, Pedro A; Emond, Charles; Gomaa, Ahmed; Remondetto, Gabriel E; Subirade, Muriel

    2015-02-01

    Whey proteins are now far more than a by-product of cheese processing. In the last 2 decades, food manufacturers have developed them as ingredients, with the dairy industry remaining as a major user. For many applications, whey proteins are modified (denatured) to alter their structure and functional properties. The objective of this research was to study the influence of 85 to 100 °C, with protein concentration of 8% to 12%, and treatment times of 5 to 30 min, while measuring rheological properties (storage modulus, loss modulus, and complex viscosity) and aggregation (intermolecular beta-sheet formation) in dispersions of whey protein concentrate (WPC). A Box-Behnken Response Surface Methodology modeled the heat denaturation of liquid sweet WPC at 3 variables and 3 levels. The model revealed a very significant fit for viscoelastic properties, and a lesser fit for protein aggregation, at temperatures not previously studied. An exponential increase of rheological parameters was governed by protein concentration and temperature, while a modest linear relationship of aggregation was governed by temperature. Models such as these can serve as valuable guides to the ingredient and dairy industries to develop target products, as whey is a major ingredient in many functional foods. © 2015 Institute of Food Technologists®

  13. Latent heat induced rotation limited aggregation in 2D ice nanocrystals

    CERN Document Server

    Bampoulis, Pantelis; Kooij, E Stefan; Lohse, Detlef; Zandvliet, Harold J W; Poelsema, Bene

    2016-01-01

    The basic science responsible for the fascinating shapes of ice crystals and snowflakes is still not understood. Insufficient knowledge of the interaction potentials and the lack of relevant experimental access to the growth process are to blame for this failure. Here, we study the growth of fractal nanostructures in a two-dimensional (2D) system, intercalated between mica and graphene. Based on our Scanning Tunneling Spectroscopy (STS) data we provide compelling evidence that these fractals are 2D ice. They grow while they are in material contact with the atmosphere at 20 $^{\\circ}$C and without significant thermal contact to the ambient. The growth is studied in-situ, in real time and space at the nanoscale. We find that the growing 2D ice nanocrystals assume a fractal shape, which is conventionally attributed to Diffusion Limited Aggregation (DLA). However, DLA requires a low mass density mother phase, in contrast to the actual currently present high mass density mother phase. Latent heat effects and conse...

  14. New insights into heat induced structural changes of pectin methylesterase on fluorescence spectroscopy and molecular modeling basis

    Science.gov (United States)

    Nistor, Oana Viorela; Stănciuc, Nicoleta; Aprodu, Iuliana; Botez, Elisabeta

    2014-07-01

    Heat-induced structural changes of Aspergillus oryzae pectin methylesterase (PME) were studied by means of fluorescence spectroscopy and molecular modeling, whereas the functional enzyme stability was monitored by inactivation studies. The fluorescence spectroscopy experiments were performed at two pH value (4.5 and 7.0). At both pH values, the phase diagrams were linear, indicating the presence of two molecular species induced by thermal treatment. A red shift of 7 nm was observed at neutral pH by increasing temperature up to 60 °C, followed by a blue shift of 4 nm at 70 °C, suggesting significant conformational rearrangements. The quenching experiments using acrylamide and iodide demonstrate a more flexible conformation of enzyme with increasing temperature, especially at neutral pH. The experimental results were complemented with atomic level observations on PME model behavior after performing molecular dynamics simulations at different temperatures. The inactivation kinetics of PME in buffer solutions was fitted using a first-order kinetics model, resulting in activation energy of 241.4 ± 7.51 kJ mol-1.

  15. Heat-induced denaturation and aggregation of ovalbumin at neutral pH described by irreversible first-order kinetics.

    Science.gov (United States)

    Weijers, Mireille; Barneveld, Peter A; Cohen Stuart, Martien A; Visschers, Ronald W

    2003-12-01

    The heat-induced denaturation kinetics of two different sources of ovalbumin at pH 7 was studied by chromatography and differential scanning calorimetry. The kinetics was found to be independent of protein concentration and salt concentration, but was strongly dependent on temperature. For highly pure ovalbumin, the decrease in nondenatured native protein showed first-order dependence. The activation energy obtained with different techniques varied between 430 and 490 kJ*mole(-1). First-order behavior was studied in detail using differential scanning calorimetry. The calorimetric traces were irreversible and highly scan rate-dependent. The shape of the thermograms as well as the scan rate dependence can be explained by assuming that the thermal denaturation takes place according to a simplified kinetic process where N is the native state, D is denatured (or another final state) and k a first-order kinetic constant that changes with temperature, according to the Arrhenius equation. A kinetic model for the temperature-induced denaturation and aggregation of ovalbumin is presented. Commercially obtained ovalbumin was found to contain an intermediate-stable fraction (IS) of about 20% that was unable to form aggregates. The denaturation of this fraction did not satisfy first-order kinetics.

  16. Jammed elastic shells - a 3D experimental soft frictionless granular system.

    Science.gov (United States)

    Jose, Jissy; Blab, Gerhard A; van Blaaderen, Alfons; Imhof, Arnout

    2015-03-07

    We present a new experimental system of monodisperse, soft, frictionless, fluorescent labeled elastic shells for the characterization of structure, universal scaling laws and force networks in 3D jammed matter. The elastic shells in a jammed packing are deformed in such a way that at each contact one of the shells buckles with a dimple and the other remain spherical, closely resembling overlapping spheres. Using confocal microscopy, we obtained 3D stacks of images of shells at different volume fractions which were subsequently processed in ImageJ software to find their coordinates. The determination of 3D coordinates involved three steps: locating the edges of shells in all 2D slices, analyzing their shape and subsequently finding their 2D coordinates, and finally determining their 3D centers by grouping the corresponding 2D coordinates. From this analysis routine we obtained particle coordinates with sub-pixel accuracy. In a contact pair we also identified the shell that underwent buckling forming a dimple by analyzing the intensity profile of a line that connects the centers of particle pairs. The amorphous structure of the packing was analyzed as a function of distance to the jamming threshold by investigating the radial distribution function, bond order parameters, contact numbers and the number of dimples per particle (buckling number), which is a unique property of this system. We find that the power law scaling of the contact number with excess volume fraction deviated from theoretical and computer simulation predictions. In addition, the buckling number also showed a similar scaling as that of the contact number with distance to the jamming transition.

  17. Promoting Inclusive Design Practice at the Global Game Jam: A Pilot Evaluation

    OpenAIRE

    Scott, Michael; Ghinea, Gheorghita; Hamilton, Ian

    2014-01-01

    Games are a popular form of entertainment. However, many computer games present unnecessary barriers to players with sensory, motor and cognitive impairments. In order to overcome such pitfalls, an awareness of their impact and a willingness to apply inclusive design practice is often necessary. The Global Game Jam offers a potential avenue to promote inclusive design practices to students of game development. As such, this paper evaluates the impact of an initiative to promote inclusive desi...

  18. Anti-Jam GPS Antennas for Wearable Dismounted Soldier Navigation Systems

    Science.gov (United States)

    2016-06-01

    resistance and reactance of the individual CNT threads, including quantum capacitance and kinetic inductance , and the finite lengths of the CNTs...antennas result when individual CNTs are employed as RF radiators due to the dominant kinetic inductance that each nanoscale CNT contributes to the...of adaptive nulling antenna used in anti-jam GPS. Proc. of 2001 CIE International Conference on Radar ; 2001 Oct. p. 1178–1181. 2. Brown A, Reynolds

  19. Detailed characterization of rattlers in exactly isostatic, strictly jammed sphere packings

    Science.gov (United States)

    Atkinson, Steven; Stillinger, Frank H.; Torquato, Salvatore

    2013-12-01

    We generate jammed disordered packings of 100≤N≤2000 monodisperse hard spheres in three dimensions whose strictly jammed backbones are demonstrated to be exactly isostatic with unprecedented numerical accuracy. This is accomplished by using the Torquato-Jiao (TJ) packing algorithm as a means of studying the maximally random jammed (MRJ) state. The rattler fraction of these packings converges towards 0.015 in the infinite-system limit, which is markedly lower than previous estimates for the MRJ state using the Lubachevsky-Stillinger protocol. This is because the packings that the TJ algorithm creates are closer to the true MRJ state, as shown using bond-orientational and translational order metrics. The rattler pair correlation statistics exhibit strongly correlated behavior contrary to the conventional understanding that they be randomly (Poisson) distributed. Dynamically interacting "polyrattlers" may be found imprisoned in shared cages as well as interacting through "bottlenecks" in the backbone and these clusters are mainly responsible for the sharp increase in the rattler pair correlation function near contact. We discover the surprising existence of polyrattlers with cluster sizes of up to five rattlers (which is expected to increase with system size) and present a distribution of polyrattler occurrence as a function of cluster size and system size. We also enumerate all of the rattler interaction topologies we observe and present images of several examples, showing that MRJ packings of monodisperse spheres can contain large rattler cages while still obeying the strict jamming criterion. The backbone spheres that encage the rattlers are significantly hypostatic, implying that correspondingly hyperstatic regions must exist elsewhere in these isostatic packings. We also observe that rattlers in hard-sphere packings share an apparent connection with the low-temperature two-level system anomalies that appear in real amorphous insulators and semiconductors.

  20. Sublethal Photothermal Stimulation with a Micropulse Laser Induces Heat Shock Protein Expression in ARPE-19 Cells

    Directory of Open Access Journals (Sweden)

    Keiji Inagaki

    2015-01-01

    Full Text Available Purpose/Aim of the Study. Subthreshold micropulse diode laser photocoagulation is an effective treatment for macular edema. The molecular mechanisms underlying treatment success are poorly understood. Therefore, we investigated the effects of sublethal laser energy doses on a single layer of densely cultured ARPE-19 cells as a model of the human retinal pigment epithelium (RPE. Materials and Methods. A single layer of densely cultured human ARPE-19 cells was perpendicularly irradiated with a micropulse diode laser. Nonirradiated cells served as controls. Sublethal laser energy was applied to form a photocoagulation-like area in the cultured cell layers. Hsp70 expression was evaluated using quantitative polymerase chain reaction and immunocytochemistry. Results. Photocoagulation-like areas were successfully created in cultured ARPE-19 cell layers using sublethal laser energy with our laser irradiation system. Hsp70 mRNA expression in cell layers was induced within 30 min of laser irradiation, peaking at 3 h after irradiation. This increase was dependent on the number of laser pulses. Hsp70 upregulation was not observed in untreated cell layers. Immunostaining indicated that Hsp70 expression occurred concentrically around laser irradiation sites and persisted for 24 h following irradiation. Conclusion. Sublethal photothermal stimulation with a micropulse laser may facilitate Hsp70 expression in the RPE without inducing cellular damage.

  1. The Med AppJam: a model for an interprofessional student-centered mHealth app competition.

    Science.gov (United States)

    Youm, Julie; Wiechmann, Warren

    2015-03-01

    The Med AppJam is a 2-week long competition where students from the University of California, Irvine School of Medicine are partnered with students from the University of California, Irvine School of Information and Computer Sciences in interprofessional teams to develop mobile health applications for use by clinicians and patients. The success of the Med AppJam comes from the unique opportunity for students to mutually contribute their content expertise to improve the clinical landscape while expanding their technology literacy and savvy. Since 2012, about 285 computer science students and over 90 medical students have collaborated to design and develop 53 iOS mHealth apps during the event. The Med AppJam model has been replicated in an Autism AppJam, a competition focused on the needs of a specific population, and with high school students in a mini Pre-Med AppJam using a paper prototyping approach. It is proposed that other medical schools consider implementation of a local Med AppJam as a viable model for engaging students in technology for healthcare.

  2. Garlic's ability to prevent in vitro Cu2+-induced lipoprotein oxidation in human serum is preserved in heated garlic: effect unrelated to Cu2+-chelation

    OpenAIRE

    Menjívar Marta; Barbachano-Esparza Laura; Albarrán Gabriela; Gil-Ortiz Mariana; Pedraza-Chaverrí José; Medina-Campos Omar N

    2004-01-01

    Abstract Background It has been shown that several extracts and compounds derived from garlic are able to inhibit Cu2+-induced low density lipoprotein oxidation. In this work we explored if the ability of aqueous garlic extract to prevent in vitro Cu2+-induced lipoprotein oxidation in human serum is affected by heating (a) aqueous garlic extracts or (b) garlic cloves. In the first case, aqueous extract of raw garlic and garlic powder were studied. In the second case, aqueous extract of boiled...

  3. Developmental and hyperthermia-induced expression of the heat shock proteins HSP60 and HSP70 in tissues of the housefly Musca domestica: an in vitro study

    Directory of Open Access Journals (Sweden)

    Sunita Sharma

    2007-01-01

    Full Text Available The expression pattern of two major chaperones, the heat shock proteins (HSPs HSP60 and HSP70 was studied in vitro in tissues of the housefly Musca domestica during larval and adult stages of development to identify their immunological relatives and understand their functional significance in normal cellular activities and during thermal stress. Fluorographs of labeled polypeptides and western blots demonstrated that both HSPs are expressed constitutively and heat-induced in all the larval and adult cell types examined. The pattern of whole tissue immunocytochemical staining using anti-HSP60 and anti-HSP70 antibodies corresponded well with the observations from western blots or fluorographs. In developing oocytes, both constitutive and heat inducible expression of HSP60 were regulated in an oocyte stage-specific manner. In unstressed ovaries the expression of these proteins was less pronounced in early stage oocytes (1st - 8th than at later stages (9th and onward. The heat shock, however, induced both HSP70 and HSP60 to a significantly high level in early stage oocytes (1st-8th as compared to their respective controls. Our findings indicate the involvement of the HSP60 and HSP70 proteins in the development, growth and differentiation of both somatic and germ line tissues. Furthermore, the enhanced co-expression of HSP70 and HSP60 upon heat shock in various larval and adult cell types suggests the possible role of HSP60 in thermoprotection.

  4. Cargo crowding at actin-rich regions along axons causes local traffic jams.

    Science.gov (United States)

    Sood, Parul; Murthy, Kausalya; Kumar, T Vinod; Nonet, Michael L; Menon, Gautam I; Koushika, Sandhya P

    2017-11-27

    Steady axonal cargo flow is central to the functioning of healthy neurons. However, a substantial fraction of cargo in axons remains stationary up to several minutes (Kang, Tian et al. 2008, Tang, Scott et al. 2012, Tang, Scott et al. 2013, Iacobucci, Rahman et al. 2014). We examine the transport of precursors of synaptic vesicles (pre-SVs), endosomes and mitochondria in C. elegans touch receptor neurons (TRNs), showing that stationary cargo are predominantly present at actin-rich regions along the neuronal process. Stationary vesicles at actin-rich regions increase the propensity of moving vesicles to stall at the same location, resulting in traffic jams arising from physical crowding. Such local traffic jams at actin-rich regions are likely to be a general feature of axonal transport since they also occur in Drosophila neurons. Repeated touch stimulation of C. elegans reduces the density of stationary pre-SVs, indicating that these traffic jams can act as both sources and sinks of vesicles. This suggests that vesicles trapped in actin-rich regions are functional reservoirs that may contribute to maintaining robust cargo flow in the neuron. This article is protected by copyright. All rights reserved.

  5. The effects of slotting, burstiness, and jamming in frequency-hopped random access systems

    Science.gov (United States)

    Clare, L. P.; Sastry, A. R. K.

    A model is defined for a frequency-hopped spread-spectrum system, and performance is derived for the aspects of system variables by both mathematical analysis and simulation. Interference is characterized at both the symbol level and the packet levels. Values for the jamming parameters a, rho(t) and rho(f) that cause maximum degradation in the users' throughput are determined. It is shown that, unlike the case of unspread systems, performance does not depend heavily on the burstiness of the user traffic or on whether slotted operation is used. As the number of frequency bins q increases, the difference in performance between slotted and unslotted operation becomes insignificant. For large q, only slightly less throughput is obtainable when the traffic is bursty as compared with continuous transmission by the users; this fact justifies the consideration of random-access techniques in a spread-spectrum environment. The effect of the jamming pulse length a is closely related to gamma, the amount of interference that a symbol can tolerate. If the jamming pulse length is large, the effect of the jammer is similar to additional user traffic of an equal load.

  6. High Speed Dim Air Target Detection Using Airborne Radar under Clutter and Jamming Effects

    Directory of Open Access Journals (Sweden)

    A. E. Almslmany

    2015-06-01

    Full Text Available The challenging potential problems associated with using airborne radar in detection of high Speed Maneuvering Dim Target (HSMDT are the highly noise, jamming and clutter effects. The problem is not only how to remove clutter and jamming as well as the range migration and Doppler ambiguity estimation problems due to high relative speed between the targets and airborne radar. Some of the recently published works ignored the range migration problems, while the others ignored the Doppler ambiguity estimation. In this paper a new hybrid technique using Optimum Space Time Adaptive Processing (OSTAP, Second Order Keystone Transform (SOKT, and the Improved Fractional Radon Transform (IFrRT was proposed. The OSTAP was applied as anti-jamming and clutter rejection method, the SOKT corrects the range curvature and part of the range walk, then the IFrRT estimates the target’ radial acceleration and corrects the residual range walk. The simulation demonstrates the validity and effectiveness of the proposed technique, and its advantages over the previous researches by comparing its probability of detection with the traditional methods. The new approach increases the probability of detection, and also overcomes the limitation of Doppler frequency ambiguity.

  7. Evaluation of anthocynin changes in blueberries and in blueberry jam after the processing and storage

    Directory of Open Access Journals (Sweden)

    Peter Czako

    2013-07-01

    Full Text Available Blueberry (Vaccinium corymbosum L. is worldwide famous as the healthy and desirable fruit. The most valuable nutritional components of fruits are polyphenols, which include anthocyanins. The aim of the study was to assess the content of anthocyanin dyes in selected varieties of blueberry fruit. We evaluated the changes in the content of colorants that occur after treatment for fruit jam and its subsequent storage at 21°C under the light. Varieties Ramcocas, Record, Iranka, Nelson, Pemberton, Jersey and Coville were observed. Content of anthocyanins was determined spectrophotometrically. In fresh fruits anthocyanin content ranged from 9.878 g kg-1 of dry matter (Jersey variety to 18.555 g kg-1 of dry matter (Nelson variety. After treatment there was found a decrease in the anthocyanins content, in the product's content were determined in the amount 1.645 g kg-1 of dry matter (Jersey variety to 3.476 g kg-1 of dry matter (variety Ramcocas. The decrease was due to decomposition of anthocyans at high temperatures in processed products and also by the replacement of dry matter by sucrose in the product. Mean color decrease in blueberry jam was 84.5%. After storage of the product, there were found further degradations of colorants, evaluated at 34.9%. The content of anthocyanin in jam was found to be 1.089 g kg-1 of dry matter (Jersey variety to 2.199 g kg-1 of dry matter (Ramcocas variety.

  8. How do generalized jamming transitions affect collective migration in confluent tissues?

    Science.gov (United States)

    Manning, M. Lisa

    Recent experiments have demonstrated that tissues involved in embryonic development, lung function, wound healing, and cancer progression are close to fluid-to-solid, or ``jamming'' transitions. Theoretical models for confluent 2D tissues have also been shown to exhibit continuous rigidity transitions. However, in vivobiological systems can differ in significant ways from the simple 2D models. For example, many tissues are three-dimensional, mechanically heterogeneous, and/or composed of mechanosensitive cells interspersed with extracellular matrix. We have extended existing models for confluent tissues to capture these features, and we find interesting predictions for collective cell motion that are ultimately related to an underlying generalized jamming transition. For example, in 2D, we find that heterogeneous mixtures of cells spontaneously self-organize into rigid regions of stiffer cells interspersed with string-like groups of soft cells, reminiscent of cellular streaming seen in cancer. We also find that alignment interactions (of the sort often explored in self-propelled particle models) alter the transition and generate interesting flocked liquid and flocked solid collective migration patterns. Our model predicts that 3D tissues also exhibit a jamming transition governed by cell shape, as well as history-dependent aging, and we are currently exploring whether ECM-like interactions in 3D models might help explain compressional stiffening seen in experiments on human tissue.

  9. Development and heat stress-induced transcriptomic changes during embryogenesis of the scleractinian coral Acropora palmata

    KAUST Repository

    Portune, Kevin J.

    2010-03-01

    Projected elevation of seawater temperatures poses a threat to the reproductive success of Caribbean reef-building corals that have planktonic development during the warmest months of the year. This study examined the transcriptomic changes that occurred during embryonic and larval development of the elkhorn coral, Acropora palmata, at a non-stressful temperature (28 °C) and further assessed the effects of two elevated temperatures (30 °C and 31.5 °C) on these expression patterns. Using cDNA microarrays, we compared expression levels of 2051 genes from early embryos and larvae at multiple developmental stages (including pre-blastula, blastula, gastrula, and planula stages) at each of the three temperatures. At 12 h post-fertilization in 28 °C treatments, genes involved in cell replication/cell division and transcription were up-regulated in A. palmata embryos, followed by a reduction in expression of these genes during later growth stages. From 24.5 to 131 h post-fertilization at 28 °C, A. palmata altered its transcriptome by up-regulating genes involved in protein synthesis and metabolism. Temperatures of 30 °C and 31.5 °C caused major changes to the A. palmata embryonic transcriptomes, particularly in the samples from 24.5 hpf post-fertilization, characterized by down-regulation of numerous genes involved in cell replication/cell division, metabolism, cytoskeleton, and transcription, while heat shock genes were up-regulated compared to 28 °C treatments. These results suggest that increased temperature may cause a breakdown in proper gene expression during development in A. palmata by down-regulation of genes involved in essential cellular processes, which may lead to the abnormal development and reduced survivorship documented in other studies. © 2010 Elsevier B.V. All rights reserved.

  10. Facile fabrication of visible light induced Bi2O3 nanorod using conventional heat treatment method

    Science.gov (United States)

    Raza, Waseem; Khan, Azam; Alam, Umair; Muneer, M.; Bahnemann, D.

    2016-03-01

    In this paper, a new Bi2O3 based photocatalyst doped with varying concentration of Nb and Mn metal ion was fabricated by conventional heat treatment method and their photocatalytic activity was investigated. The prepared material was characterized by X-ray diffraction (XRD), UV-Visible Spectroscopy, Fourier transform infrared (FTIR) and Scanning Electron Microscopic (SEM) techniques. The XRD analysis of synthesized photocatalyst was found to exhibit characteristic peaks of well crystallized monoclinic α-Bi2O3. The XRD pattern of pure and metal doped Bi2O3 were found to more or less similar. The crystallite size of doped materials were smaller than pure Bi2O3 and size decreases with increasing dopant concentration from 0.5 to 2.0% for Nb & 1.0-3.0% for Mn and remains almost constant at higher dopant concentration. The SEM analysis clearly indicate the formation of nanorod like morphologies. The UV-Vis absorption spectra of synthesized nanorods revealed that the absorption edge shift towards longer wavelength on doping with Nb and Mn metal ions which is beneficial for absorbing more visible light in the solar spectrum. The prepared doped Bi2O3 nanorod showed the excellent photocatalytic activity for degradation of selected organic pollutants, such as Methylene Blue (MB) and Rodaamime B (RhB) under visible light source. The higher activity of doped Bi2O3 nanorod may be attributed to absorption of more visible light leading to generation of higher photogenerated electron hole pairs and efficient separation of photoinduced charge carrier to inhibit the recombination rate.

  11. Biofilm Formation and Heat Stress Induce Pyomelanin Production in Deep-Sea Pseudoalteromonas sp. SM9913

    Directory of Open Access Journals (Sweden)

    Zhenshun Zeng

    2017-09-01

    Full Text Available Pseudoalteromonas is an important bacterial genus present in various marine habitats. Many strains of this genus are found to be surface colonizers on marine eukaryotes and produce a wide range of pigments. However, the exact physiological role and mechanism of pigmentation were less studied. Pseudoalteromonas sp. SM9913 (SM9913, an non-pigmented strain isolated from the deep-sea sediment, formed attached biofilm at the solid–liquid interface and pellicles at the liquid–air interface at a wide range of temperatures. Lower temperatures and lower nutrient levels promoted the formation of attached biofilm, while higher nutrient levels promoted pellicle formation of SM9913. Notably, after prolonged incubation at higher temperatures growing planktonically or at the later stage of the biofilm formation, we found that SM9913 released a brownish pigment. By comparing the protein profile at different temperatures followed by qRT-PCR, we found that the production of pigment at higher temperatures was due to the induction of melA gene which is responsible for the synthesis of homogentisic acid (HGA. The auto-oxidation of HGA can lead to the formation of pyomelanin, which has been shown in other bacteria. Fourier Transform Infrared Spectrometer analysis confirmed that the pigment produced in SM9913 was pyomelanin-like compound. Furthermore, we demonstrated that, during heat stress and during biofilm formation, the induction level of melA gene was significantly higher than that of the hmgA gene which is responsible for the degradation of HGA in the L-tyrosine catabolism pathway. Collectively, our results suggest that the production of pyomelanin of SM9913 at elevated temperatures or during biofilm formation might be one of the adaptive responses of marine bacteria to environmental cues.

  12. Smoking induces transcription of the heat shock protein system in the joints.

    Science.gov (United States)

    Ospelt, Caroline; Camici, Giovanni G; Engler, Anna; Kolling, Christoph; Vogetseder, Alexander; Gay, Renate E; Michel, Beat A; Gay, Steffen

    2014-07-01

    Smoking increases the risk of developing rheumatoid arthritis (RA) and worsens the course of the disease. In the current study we analysed whether smoking can affect gene expression directly in the joints. Synovial fibroblasts were incubated with 5% cigarette smoke extract and changes in gene expression were detected using whole genome microarrays and verified with real-time PCR. Synovial tissues were obtained from smoking and non-smoking patients with RA undergoing joint replacement surgery and from mice exposed to cigarette smoke or ambient air in a whole body exposure chamber for 3 weeks. Microarray and real-time PCR analysis showed a significant upregulation of the heat shock proteins DnaJA4, DnaJB4, DnaJC6, HspB8 and Hsp70 after stimulation of synovial fibroblasts with 5% cigarette smoke extract. Similarly, in synovial tissues of smokers with RA the expression of DnaJB4, DnaJC6, HspB8 and Hsp70 was significantly higher compared with non-smokers with RA. Upregulation of DnaJB4 and DnaJC6 in joints by smoking was also confirmed in mice exposed to cigarette smoke. Our data clearly show that smoking can change gene expression in the joints, which can lead to the activation of signalling pathways that promote development of autoimmunity and chronic joint inflammation. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  13. Heat stress does not exacerbate tennis-induced alterations in physical performance

    Science.gov (United States)

    Girard, Olivier; Christian, Ryan J; Racinais, Sébastien; Périard, Julien D

    2014-01-01

    Objectives To assess the time course of changes in physical performance in response to match-play tennis under heat stress. Methods Two matches consisting of 20 min of effective playing time (2×10 min segments) were played in COOL (∼102 min; ∼22°C and 70% relative humidity (RH)) and HOT (∼119 min; ∼36°C and 35% RH) environments. Repeated-sprint ability (3×15 m, 15 s rest), 15 m sprint time with a direction change (180°), vertical jump height (squat and countermovement jumps) and leg stiffness (multirebound jumps) were assessed in 12 competitive male players prematch, midmatch and postmatch, and 24 and 48 h after match completion. Results During the repeated-sprint ability test, initial (+2.3% and +3.1%) and cumulated sprint (+1.5% and +2.8%) times increased from prematch to midmatch and postmatch, respectively (pheight (−1.5% and −2.4%; p=0.05), but not countermovement jump height (−0.7% and −1.3%; p>0.05), decreased midmatch and postmatch, respectively, regardless of the condition. Complete recovery in all physical performance markers occurred within 24 h. Conclusions In tennis, match-related fatigue is characterised by impaired repeated-sprint ability, explosive power and leg stiffness at midmatch and postmatch, with values restored to prematch baseline 24 h into recovery. In addition, physical performance responses (match and recovery kinetics) are identical when competing in cool and hot environments. PMID:24668378

  14. Time-resolved microscopy of fs-laser-induced heat flows in glasses

    Science.gov (United States)

    Bonse, Jörn; Seuthe, Thomas; Grehn, Moritz; Eberstein, Markus; Rosenfeld, Arkadi; Mermillod-Blondin, Alexandre

    2018-01-01

    Time-resolved phase-contrast microscopy is employed to visualize spatio-temporal thermal transients induced by tight focusing of a single Ti:sapphire fs-laser pulse into a solid dielectric sample. This method relies on the coupling of the refractive index change and the sample temperature through the thermo-optic coefficient d n/d T. The thermal transients are studied on a timescale ranging from 10 ns up to 0.1 ms after laser excitation. Beyond providing direct insights into the laser-matter interaction, analyzing the results obtained also enables quantifying the local thermal diffusivity of the sample on a micrometer scale. Studies conducted in different solid dielectrics, namely amorphous fused silica (a-SiO2), a commercial borosilicate glass (BO33, Schott), and a custom alkaline earth silicate glass (NaSi66), illustrate the applicability of this approach to the investigation of various glassy materials.

  15. Gamma-effects on 2-dimensional transonic aerodynamics. [specific heat ratio due to shock induced separation

    Science.gov (United States)

    Tuzla, K.; Russell, D. A.; Wai, J. C.

    1976-01-01

    Nonlifting 10% biconvex airfoils are mounted in a 30 x 40 cm Ludwieg-tube-driven transonic test-section and the flow field recorded with a holographic interferometer. Nitrogen, argon, and carbon dioxide are used as the principal test gases. Experiments are conducted with Reynolds number based on chord of (0.5-3.5) x 10 to the 6th with Mach numbers of 0.70, 0.75, and 0.80. Supporting calculations use inviscid transonic small-disturbance and full-potential computer codes coupled with simple integral boundary-layer modeling. Systematic studies show that significant gamma-effects can occur due to shock-induced separation.

  16. Effect of extraction pH on heat-induced aggregation, gelation and microstructure of protein isolate from quinoa (Chenopodium quinoa Willd)

    NARCIS (Netherlands)

    Ruiz, Geraldine Avila; Xiao, Wukai; Boekel, van Tiny; Minor, Marcel; Stieger, Markus

    2016-01-01

    The aim of this study was to determine the influence of extraction pH on heat-induced aggregation, gelation and microstructure of suspensions of protein isolates extracted from quinoa (Chenopodium quinoa Willd). Quinoa seed protein was extracted by alkaline treatment at various pH values (pH 8

  17. Long-term efficacy of single-dose radiofrequency-induced heat therapy vs. intralesional antimonials for cutaneous leishmaniasis in India

    NARCIS (Netherlands)

    Bumb, R.A.; Prasad, N.; Khandelwal, K.; Aara, N.; Mehta, R.D.; Ghiya, B.C.; Salotra, P.; Wei, L.; Peters, S.; Satoskar, A.R.

    2013-01-01

    Background Radiofrequency-induced heat therapy (RFHT) has been found to be safe and effective against cutaneous leishmaniasis (CL) in the short term, but its long-term efficacy is unclear. Objectives To compare the long-term efficacy of RFHT vs. intralesional sodium stibogluconate (SSG) injections

  18. Sensitivity analysis of hydraulic and thermal parameters inducing anomalous heat flow in the Lower Yarmouk Gorge

    Science.gov (United States)

    Goretzki, Nora; Inbar, Nimrod; Kühn, Michael; Möller, Peter; Rosenthal, Eliyahu; Schneider, Michael; Siebert, Christian; Magri, Fabien

    2016-04-01

    manual 5th Edition. Watermark, Brisbane, Australia [3] Diersch H.-J.G. (2014) FEFLOW Finite Element Modeling of Flow, Mass and Heat Transport in Porous and Fractured Media. Springer- Verlag Berlin Heidelberg, 996p

  19. Effect of Ultrastructure on Changes of Textural Characteristics between Crisp Grass Carp (Ctenopharyngodon Idellus C.Et V) and Grass Carp (Ctenopharyngodon Idellus) Inducing Heating Treatment.

    Science.gov (United States)

    Lin, Wan-Ling; Yang, Xian-Qing; Li, Lai-Hao; Hao, Shu-Xian; Wang, Jin-Xu; Huang, Hui; Wei, Ya; Wu, Yan-Yan

    2016-02-01

    The research studies the ultrastructure effect on texture of crisp grass carp (CGC) and grass carp (GC) fillets inducing heating for 15, 25, and 40 min with boiling water. After heating, the hardness, fracturability, springiness, chewiness, resilience, and cohesiveness of CGC were higher than that of raw CGC, whereas the all textural characteristics of heating GC were lower obviously than that of raw GC. The hardness, fracturability, springiness, chewiness, resilience, and cohesiveness of CGC for heating 15 min were higher by 6.3%, 9.0%, 27.0%, 71.8%, 9.4%, and 23.9%, respectively, than that of raw CGC (RCGC). The hardness increasing of CGC flesh with the extension of heating time related closely to more coagulating connective tissue in interstitial spaces, especially relating to smaller muscle fiber diameter and denser muscle fiber density. The more and larger spaces between fiber and fiber with the extension of heating time results in the decrease of cohesiveness and resilience of CGC flesh. For chewiness, the stronger chewiness of cooked CGC associated with more detachment of myofiber-myocommata and fiber-fiber. Overall, the results show that the changes of texture characteristics of CGC fillet with extension of heating time correlates positively with the ultrastructure. © 2016 Institute of Food Technologists®

  20. Reactive oxygen species induced by heat stress during grain filling of rice (Oryza sativa L.) are involved in occurrence of grain chalkiness.

    Science.gov (United States)

    Suriyasak, Chetphilin; Harano, Keisuke; Tanamachi, Koichiro; Matsuo, Kazuhiro; Tamada, Aina; Iwaya-Inoue, Mari; Ishibashi, Yushi

    2017-09-01

    Heat stress during grain filling increases rice grain chalkiness due to increased activity of α-amylase, which hydrolyzes starch. In rice and barley seeds, reactive oxygen species (ROS) produced after imbibition induce α-amylase activity via regulation of gibberellin (GA) and abscisic acid (ABA) levels during seed germination. Here, we examined whether ROS is involved in induction of grain chalkiness by α-amylase in developing rice grains under heat stress. To elucidate the role of ROS in grain chalkiness, we grew post-anthesis rice plants (Oryza sativa L. cv. Koshihikari) under control (25°C) or heat stress (30°C) conditions with or without antioxidant (dithiothreitol) treatment. The developing grains were analyzed for expression of NADPH oxidases, GA biosynthesis genes (OsGA3ox1, OsGA20ox1), ABA catabolism genes (OsABA8'OH1, OsABA8'OH2) and an α-amylase gene (OsAmy3E), endogenous H 2 O 2 content and the grain quality. In grains exposed to heat stress, the expression of NADPH oxidase genes (especially, OsRbohB, OsRbohD, OsRbohF and OsRbohI) and the ROS content increased. Heat stress also increased the expression of OsGA3ox1, OsGA20ox1, OsABA8'OH1, OsABA8'OH2 and OsAmy3E. On the other hand, dithiothreitol treatment reduced the effects of heat stress on the expression of these genes and significantly reduced grain chalkiness induced by heat stress. These results suggest that, similar to cereal seed germination mechanism, ROS produced under heat stress is involved in α-amylase induction in maturating rice grains through GA/ABA metabolism, and consequently caused grain chalkiness. Copyright © 2017 Elsevier GmbH. All rights reserved.