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Sample records for activity images fig

  1. Floral ratios in the figs of Ficus montana span the range from actively to passively pollinated fig trees

    NASA Astrophysics Data System (ADS)

    Suleman, Nazia; Quinnell, Rupert J.; Compton, Stephen G.

    2014-05-01

    Fig trees (Ficus spp., Moraceae) and their associated obligate pollinator fig wasps (Agaonidae) are partners in what is often a pair-wise species-specific association. Their interaction centres on the unique enclosed inflorescence of Ficus species - the fig. Among dioecious fig tree species, only pollinated ovules in figs on female trees develop into seeds. On male trees, galled ovules support development of the fig wasp offspring that will transport their pollen, but no seeds develop. Some fig wasp species actively collect and disperse pollen, whereas others are typical insect pollinators in that pollen is transferred passively. Active pollination is associated with improved larval survivorship in pollinated figs. Because active pollination is much more efficient, their host figs need to contain far fewer male flowers and across numerous Ficus species anther-ovule ratios are a good predictor of pollination mode. We examined variation in inflorescence size and floral ratios among male figs of the Asian Ficus montana and its consequences for the amounts of pollen that would be available for each pollinator to collect. Inflorescence size (total flower number) was highly variable, and female pollinator offspring production was higher in figs with more female flowers. Pollinator offspring numbers and anther-ovule ratios were also highly variable, and encompassed the range typical of both actively and passively pollinated fig tree species. In combination, this variation resulted in large differences in the extent to which pollinators were competing for access to pollen, with potential fitness consequences for both partners in the mutualism.

  2. An image-processing software package: UU and Fig for optical metrology applications

    NASA Astrophysics Data System (ADS)

    Chen, Lujie

    2013-06-01

    Modern optical metrology applications are largely supported by computational methods, such as phase shifting [1], Fourier Transform [2], digital image correlation [3], camera calibration [4], etc, in which image processing is a critical and indispensable component. While it is not too difficult to obtain a wide variety of image-processing programs from the internet; few are catered for the relatively special area of optical metrology. This paper introduces an image-processing software package: UU (data processing) and Fig (data rendering) that incorporates many useful functions to process optical metrological data. The cross-platform programs UU and Fig are developed based on wxWidgets. At the time of writing, it has been tested on Windows, Linux and Mac OS. The userinterface is designed to offer precise control of the underline processing procedures in a scientific manner. The data input/output mechanism is designed to accommodate diverse file formats and to facilitate the interaction with other independent programs. In terms of robustness, although the software was initially developed for personal use, it is comparably stable and accurate to most of the commercial software of similar nature. In addition to functions for optical metrology, the software package has a rich collection of useful tools in the following areas: real-time image streaming from USB and GigE cameras, computational geometry, computer vision, fitting of data, 3D image processing, vector image processing, precision device control (rotary stage, PZT stage, etc), point cloud to surface reconstruction, volume rendering, batch processing, etc. The software package is currently used in a number of universities for teaching and research.

  3. Antioxidant activities and anthocyanin content of fresh fruits of common fig (Ficus carica L.).

    PubMed

    Solomon, Anat; Golubowicz, Sara; Yablowicz, Zeev; Grossman, Shlomo; Bergman, Margalit; Gottlieb, Hugo E; Altman, Arie; Kerem, Zohar; Flaishman, Moshe A

    2006-10-01

    Fig fruit has been a typical component in the health-promoting Mediterranean diet for millennia. To study the potential health-promoting constituents of fig fruits, six commercial fig varieties differing in color (black, red, yellow, and green) were analyzed for total polyphenols, total flavonoids, antioxidant capacity, and amount and profile of anthocyanins. Using reversed-phase liquid chromatography (RP-LC), various concentrations of anthocyanins but a similar profile was found in all varieties studied. Hydrolysis revealed cyanidin as the major aglycon. Proton and carbon NMR confirmed cyanidin-3-O-rhamnoglucoside (cyanidin-3-O-rutinoside; C3R) as the main anthocyanin in all fruits. Color appearance of fig extract correlated well with total polyphenols, flavonoids, anthocyanins, and antioxidant capacity. Extracts of darker varieties showed higher contents of phytochemicals compared to lighter colored varieties. Fruit skins contributed most of the above phytochemicals and antioxidant activity compared to the fruit pulp. Antioxidant capacity correlated well with the amounts of polyphenols and anthocyanins (R2 = 0.985 and 0.992, respectively). In the dark-colored Mission and the red Brown-Turkey varieties, the anthocyanin fraction contributed 36 and 28% of the total antioxidant capacity, respectively. C3R contributed 92% of the total antioxidant capacity of the anthocyanin fraction. Fruits of the Mission variety contained the highest levels of polyphenols, flavonoids, and anthocyanins and exhibited the highest antioxidant capacity. PMID:17002444

  4. Some pollinators are more equal than others: Factors influencing pollen loads and seed set capacity of two actively and passively pollinating fig wasps

    NASA Astrophysics Data System (ADS)

    Kjellberg, Finn; Suleman, Nazia; Raja, Shazia; Tayou, Abelouahad; Hossaert-McKey, Martine; Compton, Stephen G.

    2014-05-01

    The nursery pollination system of fig trees (Ficus) results in the plants providing resources for pollinator fig wasp larvae as part of their male reproductive investment, with selection determining relative investment into pollinating wasps and the pollen they carry. The small size of Ficus pollen suggests that the quantities of pollen transported by individual wasps often limits male reproductive success. We assessed variation in fig wasp pollen loads and its influence on seed production in actively pollinated (Ficus montana) and passively pollinated (Ficus carica) dioecious fig trees.

  5. Extremely high proportions of male flowers and geographic variation in floral ratios within male figs of Ficus tikoua despite pollinators displaying active pollen collection.

    PubMed

    Deng, Jun-Yin; Fu, Rong-Hua; Compton, Stephen G; Hu, Dai-Mei; Zhang, Lu-Shui; Yang, Fan; Chen, Yan; Kjellberg, Finn

    2016-01-01

    Most plants are pollinated passively, but active pollination has evolved among insects that depend on ovule fertilization for larval development. Anther-to-ovule ratios (A/O ratios, a coarse indicator of pollen-to-ovule ratios) are strong indicators of pollination mode in fig trees and are consistent within most species. However, unusually high values and high variation of A/O ratios (0.096-10.0) were detected among male plants from 41 natural populations of Ficus tikoua in China. Higher proportions of male (staminate) flowers were associated with a change in their distribution within the figs, from circum-ostiolar to scattered. Plants bearing figs with ostiolar or scattered male flowers were geographically separated, with scattered male flowers found mainly on the Yungui Plateau in the southwest of our sample area. The A/O ratios of most F. tikoua figs were indicative of passive pollination, but its Ceratosolen fig wasp pollinator actively loads pollen into its pollen pockets. Additional pollen was also carried on their body surface and pollinators emerging from scattered-flower figs had more surface pollen. Large amounts of pollen grains on the insects' body surface are usually indicative of a passive pollinator. This is the first recorded case of an actively pollinated Ficus species producing large amounts of pollen. Overall high A/O ratios, particularly in some populations, in combination with actively pollinating pollinators, may reflect a response by the plant to insufficient quantities of pollen transported in the wasps' pollen pockets, together with geographic variation in this pollen limitation. This suggests an unstable scenario that could lead to eventual loss of wasp active pollination behavior. PMID:26843943

  6. Figs and fig wasps: evolution in a microcosm.

    PubMed

    Cook, J M; Lopez-Vaamonde, C

    2001-06-01

    Fig wasps are tiny insects that both pollinate and feed upon fig plants. Each species requires the other in order to complete its reproductive cycle. The interaction centres on the unique structure of syconium (fig inflorescence), which provides an intriguing and convenient microcosm for studying the action of both natural and sexual selection. PMID:11399840

  7. New Viruses Identified in Fig Trees Exhibiting Fig Mosaic Disease

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fig mosaic disease has been known for decades, but the causal agent has been elusive. Here we present data on the incidence of at least four new viruses isolated from fig trees exhibiting mosaic symptoms. One of the viruses is closely related to the recently identified European mountain ash ringspo...

  8. Assessment of the distribution of phenolic compounds and contribution to the antioxidant activity in Tunisian fig leaves, fruits, skins and pulps using mass spectrometry-based analysis.

    PubMed

    Ammar, Sonda; del Mar Contreras, María; Belguith-Hadrich, Olfa; Segura-Carretero, Antonio; Bouaziz, Mohamed

    2015-12-01

    The phenolic composition of leaves, fruits, skins and pulps from two F. carica cultivars, 'Temri' and 'Soltani', was studied in order to understand its contribution to the antioxidant activity. A total of 116 compounds were characterized based on the results obtained by reversed-phase ultra-high performance liquid chromatography coupled to diode array and mass spectrometry detection. In general, the leaves of both cultivars and the skin of 'Soltani' presented richer qualitative profiles compared to the other plant parts. Using the negative ionization mode, qualitative profiles of the same part of the studied figs were similar. In this regard, rutin was the main compound in fruits, skins and leaves, but with different relative amounts. Alternatively, an isomer of prenylhydroxygenistein was the major compound in the pulps. In the positive ionization mode, 9 anthocyanins were characterized in 'Soltani' skin, only two of them being also present in the green cultivar 'Temri'. The main anthocyanins were cyanidin 3-rutinoside and cyanidin 3,5-diglucoside, depending on the cultivar and fruit part. In this ionization mode, 15 furanocoumarins were also detected in the leaves of both the studied cultivars with methoxypsoralen and psoralen being the most relatively abundant. In addition, our findings showed a good correlation between the antioxidant activity, total phenol content, and abundance of some phenolic subfamilies such as hydroxybenzoic acids, flavonols, flavones, hydroxycoumarins and furanocoumarins with r > 0.97. PMID:26390136

  9. Active imaging at DARPA

    NASA Astrophysics Data System (ADS)

    Ricklin, J. C.; Tomlinson, P. G.

    2005-08-01

    Active systems, because they provide their own illumination, are capable of operating 24 hours a day and are not dependent upon the angle of the sun. Unlike passive systems, they can provide three-dimensional imaging. DARPA is currently developing systems, technologies, and signal processing to pioneer new or improve existing capabilities that employ active imaging capabilities. These involve both radar and ladar, ranging from a few MHz for foliage penetration to near-visible IR to achieve ultra-high resolution at long range. These capabilities would improve Battlefield Awareness (BA) and provide persistent Intelligence, Surveillance, and Reconnaissance (ISR) to perform target detection, recognition, and identification. This paper discusses two different approaches to active optical imaging. One is a coherent approach that uses synthetic aperture techniques with infrared laser radar, and another approach uses only the intensity of the speckle pattern in the aperture plane. Both are capable of producing ultra-high resolution at long range.

  10. Pacesetters of the American image or (a case for a pleasant diversion).

    PubMed Central

    Hook, E. W.

    1992-01-01

    Regardless of how you resolve the morality of our history, the fact is that Currier and Ives documented in their own special and often biased way the iconography of the growth and development of the United States of America (Fig. 88) in some of the most eventful years of its history from about 1840 through 1895. Now, as we near our 500th anniversary commemoration of Columbus' voyage to the Americas, it seems especially appropriate to review--to think about all of this. I think you have sensed, as we have gone along, that learning about Currier and his colleagues--these pacesetters of the American Image--has meant, as Osler predicted, a pleasant diversion for me. These activities have carried me into new areas of interest, expanding my perspective of the American Image--of people, of medicine, of life in general, and aiding in the identification of values, my own, as well as those of others. All along, my knowledge has been enhanced, especially of the history of this wonderful complex country of ours. Furthermore, and of considerable importance, this endeavor has sharpened my power of observation. I have, like a good doctor should do, learned to look better! Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11 Fig. 12 Fig. 13 Fig. 14 Fig. 15 Fig. 16 Fig. 17 Fig. 19 Fig. 18 Fig. 20 Fig. 21 Fig. 23 Fig. 25 Fig. 27 Fig. 26 Fig. 28 Fig. 29 Fig. 30 Fig. 31 Fig. 32 Fig. 33 Fig. 34 Fig. 35 Fig. 36 Fig. 37 Fig. 39 Fig. 40 Fig. 41 Fig. 42 Fig. 43 Fig. 44 Fig. 45 Fig. 46 Fig. 47 Fig. 48 Fig. 49 Fig. 50 Fig. 51 Fig. 52 Fig. 53 Fig. 54 Fig. 55 Fig. 56 Fig. 57 Fig. 58 Fig. 59 Fig. 60 Fig. 61 Fig. 62 Fig. 63 Fig. 64 Fig. 65 Fig. 66 Fig. 68 Fig. 67 Fig. 69 Fig. 70 Fig. 71 Fig. 72 Fig. 73 Fig. 74 Fig. 75 Fig. 76 Fig. 77 Fig. 78 Fig. 79 Fig. 80 Fig. 82 Fig. 81 Fig. 83 Fig. 84 Fig. 85 Fig. 86 Fig. 87 Fig. 88 PMID:1413369

  11. Climate warming and the potential extinction of fig wasps, the obligate pollinators of figs

    PubMed Central

    Jevanandam, Nanthinee; Goh, Alexander G. R.; Corlett, Richard T.

    2013-01-01

    Figs (Ficus) have a reciprocally obligate mutualism with tiny, short-lived (1–2 days) fig wasps (Agaonidae). The small size and short life of these pollinators is expected to make them more vulnerable to climate change than their larger and longer-lived hosts. We experimentally tested the thermal tolerances of four species of adult female fig wasp from equatorial Singapore. The results suggest that an increase of 3°C or more above the current temperatures experienced across much of the equatorial tropics would markedly decrease the active adult lifespan of all four species. Fig plants are the centre of an intricate web of specialist and generalist animals. Unless fig wasps can acclimate or adapt to warmer temperatures in time, these responses may disrupt the mutualism, potentially affecting multiple trophic levels. PMID:23515979

  12. How to be an ant on figs

    NASA Astrophysics Data System (ADS)

    Bain, Anthony; Harrison, Rhett D.; Schatz, Bertrand

    2014-05-01

    Mutualistic interactions are open to exploitation by one or other of the partners and a diversity of other organisms, and hence are best understood as being embedded in a complex network of biotic interactions. Figs participate in an obligate mutualism in that figs are dependent on agaonid fig wasps for pollination and the wasps are dependent on fig ovules for brood sites. Ants are common insect predators and abundant in tropical forests. Ants have been recorded on approximately 11% of fig species, including all six subgenera, and often affect the fig-fig pollinator interaction through their predation of either pollinating and parasitic wasps. On monoecious figs, ants are often associated with hemipterans, whereas in dioecious figs ants predominantly prey on fig wasps. A few fig species are true myrmecophytes, with domatia or food rewards for ants, and in at least one species this is linked to predation of parasitic fig wasps. Ants also play a role in dispersal of fig seeds and may be particularly important for hemi-epiphytic species, which require high quality establishment microsites in the canopy. The intersection between the fig-fig pollinator and ant-plant systems promises to provide fertile ground for understanding mutualistic interactions within the context of complex interaction networks.

  13. Host sanctions and pollinator cheating in the fig tree–fig wasp mutualism

    PubMed Central

    Jandér, K. Charlotte; Herre, Edward Allen

    2010-01-01

    Theory predicts that mutualisms should be vulnerable to invasion by cheaters, yet mutualistic interactions are both ancient and diverse. What prevents one partner from reaping the benefits of the interaction without paying the costs? Using field experiments and observations, we examined factors affecting mutualism stability in six fig tree–fig wasp species pairs. We experimentally compared the fitness of wasps that did or did not perform their most basic mutualistic service, pollination. We found host sanctions that reduced the fitness of non-pollinating wasps in all derived, actively pollinated fig species (where wasps expend time and energy pollinating), but not in the basal, passively pollinated fig species (where wasps do not). We further screened natural populations of pollinators for wasp individuals that did not carry pollen (‘cheaters’). Pollen-free wasps occurred only in actively pollinating wasp species, and their prevalence was negatively correlated with the sanction strength of their host species. Combined with previous studies, our findings suggest that (i) mutualisms can show coevolutionary dynamics analogous to those of ‘arms races’ in overtly antagonistic interactions; (ii) sanctions are critical for long-term mutualism stability when providing benefits to a host is costly, and (iii) there are general principles that help maintain cooperation both within and among species. PMID:20071379

  14. Spatial heterogeneity and host repression in fig-fig wasp mutualism.

    PubMed

    Wang, RuiWu; Wen, XiaoLan; Chen, Chun; Shi, Lei; Compton, Stephen G

    2015-05-01

    It is generally believed that physical heterogeneity in common resource or evolutionary restraint can sufficiently prevent direct conflict between host and symbionts in mutualism systems. Our data on fig/fig wasp reciprocal mutualism (Ficus racemosa), however, show that structural barriers of female flowers or genetic constraints of pollinators previously hypothesized exist, but cannot sufficiently maintain the mutualism stability. The results show that a positive relationship between seed and wasp production could be maintained in warm season, which might be because of density dependence restraint among foundresses and their low oviposition and pollination efficiency, keeping common resource (female flowers) utilization unsaturated. Whilst, a negative correlation between wasp offspring and viable seed production was also observed in cold season, which might be that the increased oviposition and pollination efficiency maximized the common resource utilization. The fitness trade-off between fig and pollinator wasps is greatly affected by environmental or ecological variations. The local stability might result from temporal low exploitation efficiency of pollinators together with interference competition among pollinators. We suggest that host repression through the active regulation of bract closure, which can create interference competition among the foundresses and prevent extra more foundresses sequential entry in fruit cavities, would help the figs avoiding the cost of over-exploitation. This essentially takes the same role as sanctioning of cheating or competitive behaviors. PMID:25863497

  15. Ecology of a fig ant-plant

    NASA Astrophysics Data System (ADS)

    Harrison, Rhett D.

    2014-05-01

    Mutualistic interactions are embedded in networks of interactions that affect the benefits accruing to the mutualistic partners. Figs and their pollinating wasps are engaged in an obligate mutualism in which the fig is dependent on the fig pollinator for pollination services and the pollinator is dependent on fig ovules for brood sites. This mutualism is exploited by non-pollinating fig wasps that utilise the same ovules, but do not provide a pollination service. Most non-pollinating wasps oviposit from outside the inflorescence (syconium), where they are vulnerable to ant predation. Ficus schwarzii is exposed to high densities of non-pollinating wasps, but Philidris sp. ants patrolling the syconia prevent them from ovipositing. Philidris rarely catch wasps, but the fig encourages the patrolling by providing a reward through extra-floral nectaries on the surface of syconia. Moreover, the reward is apparently only produced during the phase when parasitoids are ovipositing. An ant-exclusion experiment demonstrated that, in the absence of ants, syconia were heavily attacked and many aborted as a consequence. Philidris was normally rare on the figs during the receptive phase or at the time of day when wasp offspring are emerging, so predation on pollinators was limited. However, Myrmicaria sp. ants, which only occurred on three trees, preyed substantially on pollinating as well as non-pollinating wasps. F. schwarzii occurs in small clusters of trees and has an exceptionally rapid crop turnover. These factors appear to promote high densities of non-pollinating wasps and, as a consequence, may have led to both a high incidence of ants on trees and increased selective pressure on fig traits that increase the payoffs of the fig-ant interaction for the fig. The fig receives no direct benefit from the reward it provides, but protects pollinating wasps that will disperse its pollen.

  16. THE FIG: OVERVIEW OF AN ANCIENT FRUIT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The fig (Ficus carica) appears to have originated in western Asia and became established throughout the Mediterranean region around 6000 years ago, reaching England by 500 A.C.E. Naming of desirable fig cultivars is recorded as early as the 4th century B.C. Even after eliminating suspected synonym...

  17. Ants use odour cues to exploit fig-fig wasp interactions

    NASA Astrophysics Data System (ADS)

    Schatz, Bertrand; Hossaert-McKey, Martine

    2010-01-01

    Fig wasps may constitute a relatively abundant food source for ants associated with the fig-fig wasp nursery pollination mutualism. We found previously that a Mediterranean ant species detects fig wasps by chemical signals. In this paper we want to test the generality of this finding by studying two tropical ants, Oecophylla smaragdina and Crematogaster sp., preying on fig wasps on the dioecious Ficus fistulosa in Brunei (Borneo). Behavioural tests in a Y-tube olfactometer showed that these two ants were attracted both to odours emitted by receptive figs and to those emitted by fig wasps (male and female of the pollinator, and a non-pollinating fig wasp) used here as a kairomone. Naïve workers were not attracted to fig wasps, suggesting that olfactory learning may play a role in prey detection. We also found that O. smaragdina was much more likely to be present on figs of male trees (where fig wasps are more abundant), and that the abundance of this ant species varied strongly with developmental phase of figs on individual trees. Moreover, its aggressiveness was also strongly influenced by the nature of the object presented in our behavioural tests, the site of the test and the developmental phase of the fig tested. Investigation on the chemical and behavioural ecology of the different interacting species provides important insights into the intricate relationships supported by the fig-fig wasp mutualism.

  18. Active Seismic Imaging Experiment

    NASA Astrophysics Data System (ADS)

    Berge, Patricia A.; Dawson, Phillip B.; Evans, John R.

    In September 1985 the U.S. Geological Survey (USGS) and Lawrence Livermore National Laboratory (LLNL) will conduct an active seismic experiment in the Medicine Lake area of northern California. The work is supported by the Geothermal Research Program of USGS and by the Geothermal and Hydropower Technologies Division of the U.S. Department of Energy. We invite interested organizations or individuals to record our explosions from Medicine Lake volcano and surrounding areas not covered by the USGS-LLNL array.

  19. The occurrence of fig wasps in the fruits of female gynodioecious fig trees

    NASA Astrophysics Data System (ADS)

    Wu, Tao; Dunn, Derek W.; Hu, Hao-Yuan; Niu, Li-Ming; Xiao, Jin-Hua; Pan, Xian-Li; Feng, Gui; Fu, Yue-Guan; Huang, Da-Wei

    2013-01-01

    Fig trees are pollinated by wasp mutualists, whose larvae consume some of the plant's ovaries. Many fig species (350+) are gynodioecious, whereby pollinators generally develop in the figs of 'male' trees and seeds generally in the 'females.' Pollinators usually cannot reproduce in 'female' figs at all because their ovipositors cannot penetrate the long flower styles to gall the ovaries. Many non-pollinating fig wasp (NPFW) species also only reproduce in figs. These wasps can be either phytophagous gallers or parasites of other wasps. The lack of pollinators in female figs may thus constrain or benefit different NPFWs through host absence or relaxed competition. To determine the rates of wasp occurrence and abundance we surveyed 11 dioecious fig species on Hainan Island, China, and performed subsequent experiments with Ficus tinctoria subsp. gibbosa to identify the trophic relationships between NPFWs that enable development in female syconia. We found NPFWs naturally occurring in the females of Ficus auriculata, Ficus hainanensis and F. tinctoria subsp. gibbosa. Because pollinators occurred only in male syconia, when NPFWs also occurred in female syconia, overall there were more wasps in male than in female figs. Species occurrence concurred with experimental data, which showed that at least one phytophagous galler NPFW is essential to enable multiple wasp species to coexist within a female fig. Individuals of galler NPFW species present in both male and female figs of the same fig species were more abundant in females than in males, consistent with relaxed competition due to the absence of pollinator. However, these wasps replaced pollinators on a fewer than one-to-one basis, inferring that other unknown mechanisms prevent the widespread exploitation by wasps of female figs. Because some NPFW species may use the holes chewed by pollinator males to escape from their natal fig, we suggest that dispersal factors could be involved.

  20. Regulation of transcription factors on sexual dimorphism of fig wasps.

    PubMed

    Sun, Bao-Fa; Li, Yong-Xing; Jia, Ling-Yi; Niu, Li-Hua; Murphy, Robert W; Zhang, Peng; He, Shunmin; Huang, Da-Wei

    2015-01-01

    Fig wasps exhibit extreme intraspecific morphological divergence in the wings, compound eyes, antennae, body color, and size. Corresponding to this, behaviors and lifestyles between two sexes are also different: females can emerge from fig and fly to other fig tree to oviposit and pollinate, while males live inside fig for all their lifetime. Genetic regulation may drive these extreme intraspecific morphological and behavioral divergence. Transcription factors (TFs) involved in morphological development and physiological activity may exhibit sex-specific expressions. Herein, we detect 865 TFs by using genomic and transcriptomic data of the fig wasp Ceratosolen solmsi. Analyses of transcriptomic data indicated that up-regulated TFs in females show significant enrichment in development of the wing, eye and antenna in all stages, from larva to adult. Meanwhile, TFs related to the development of a variety of organs display sex-specific patterns of expression in the adults and these may contribute significantly to their sexual dimorphism. In addition, up-regulated TFs in adult males exhibit enrichment in genitalia development and circadian rhythm, which correspond with mating and protandry. This finding is consistent with their sex-specific behaviors. In conclusion, our results strongly indicate that TFs play important roles in the sexual dimorphism of fig wasps. PMID:26031454

  1. Asymmetric interaction and indeterminate fitness correlation between cooperative partners in the fig-fig wasp mutualism.

    PubMed

    Wang, Rui-Wu; Sun, Bao-Fa; Zheng, Qi; Shi, Lei; Zhu, Lixing

    2011-10-01

    Empirical observations have shown that cooperative partners can compete for common resources, but what factors determine whether partners cooperate or compete remain unclear. Using the reciprocal fig-fig wasp mutualism, we show that nonlinear amplification of interference competition between fig wasps-which limits the fig wasps' ability to use a common resource (i.e. female flowers)-keeps the common resource unsaturated, making cooperation locally stable. When interference competition was manually prevented, the fitness correlation between figs and fig wasps went from positive to negative. This indicates that genetic relatedness or reciprocal exchange between cooperative players, which could create spatial heterogeneity or self-restraint, was not sufficient to maintain stable cooperation. Moreover, our analysis of field-collected data shows that the fitness correlation between cooperative partners varies stochastically, and that the mainly positive fitness correlation observed during the warm season shifts to a negative correlation during the cold season owing to an increase in the initial oviposition efficiency of each fig wasp. This implies that the discriminative sanction of less-cooperative wasps (i.e. by decreasing the egg deposition efficiency per fig wasp) but reward to cooperative wasps by fig, a control of the initial value, will facilitate a stable mutualism. Our finding that asymmetric interaction leading to an indeterminate fitness interaction between symbiont (i.e. cooperative actors) and host (i.e. recipient) has the potential to explain why conflict has been empirically observed in both well-documented intraspecific and interspecific cooperation systems. PMID:21490005

  2. Asymmetric or diffusive co-evolution generates meta-populations in fig-fig wasp mutualisms.

    PubMed

    Wang, RuiWu; Yang, Yan; Wiggins, Natasha L

    2014-06-01

    Co-evolutionary theory assumes co-adapted characteristics are a positive response to counter those of another species, whereby co-evolved species reach an evolutionarily stable interaction through bilateral adaptation. However, evidence from the fig-fig wasp mutualistic system implies very different co-evolutionary selection mechanisms, due to the inherent conflict among interacted partners. Fig plants appear to have discriminatively enforced fig wasps to evolve "adaptation characteristics" that provide greater benefit to the fig, and fig wasps appear to have diversified their evolutionary strategies in response to discriminative enforcement by figs and competition among different fig wasp species. In what appears to be an asymmetric interaction, the prosperity of cooperative pollinating wasps should inevitably lead to population increases of parasitic individuals, thus resulting in localized extinctions of pollinating wasps. In response, the sanctioning of parasitic wasps by the fig should lead to a reduction in the parasitic wasp population. The meta-populations created by such asymmetric interactions may result in each population of coevolved species chaotically oscillated, temporally or evolutionarily. PMID:24829105

  3. ALA Pretreatment Improves Waterlogging Tolerance of Fig Plants

    PubMed Central

    An, Yuyan; Qi, Lin; Wang, Liangju

    2016-01-01

    5-aminolevulinic acid (ALA), a natural and environmentally friendly plant growth regulator, can improve plant tolerance to various environmental stresses. However, whether ALA can improve plant waterlogging tolerance is unknown. Here, we investigated the effects of ALA pretreatment on the waterlogging-induced damage of fig (Ficus carica Linn.) plants, which often suffer from waterlogging stress. ALA pretreatment significantly alleviated stress-induced morphological damage, increased leaf relative water content (RWC), and reduced leaf superoxide anion (O2⋅¯) production rate and malonaldehyde (MDA) content in fig leaves, indicating ALA mitigates waterlogging stress of fig plants. We further demonstrated that ALA pretreatment largely promoted leaf chlorophyll content, photosynthetic electron transfer ability, and photosynthetic performance index, indicating ALA significantly improves plant photosynthetic efficiency under waterlogging stress. Moreover, ALA pretreatment significantly increased activities of leaf superoxide dismutase (SOD) and peroxidase (POD), root vigor, and activities of root alcohol dehydrogenase (ADH), and lactate dehydrogenase (LDH), indicating ALA also significantly improves antioxidant ability and root function of fig plants under waterlogging stress. Taken together, ALA pretreatment improves waterlogging tolerance of fig plants significantly, and the promoted root respiration, leaf photosynthesis, and antioxidant ability may contribute greatly to this improvement. Our data firstly shows that ALA can improve plant waterlogging tolerance. PMID:26789407

  4. ALA Pretreatment Improves Waterlogging Tolerance of Fig Plants.

    PubMed

    An, Yuyan; Qi, Lin; Wang, Liangju

    2016-01-01

    5-aminolevulinic acid (ALA), a natural and environmentally friendly plant growth regulator, can improve plant tolerance to various environmental stresses. However, whether ALA can improve plant waterlogging tolerance is unknown. Here, we investigated the effects of ALA pretreatment on the waterlogging-induced damage of fig (Ficus carica Linn.) plants, which often suffer from waterlogging stress. ALA pretreatment significantly alleviated stress-induced morphological damage, increased leaf relative water content (RWC), and reduced leaf superoxide anion ([Formula: see text]) production rate and malonaldehyde (MDA) content in fig leaves, indicating ALA mitigates waterlogging stress of fig plants. We further demonstrated that ALA pretreatment largely promoted leaf chlorophyll content, photosynthetic electron transfer ability, and photosynthetic performance index, indicating ALA significantly improves plant photosynthetic efficiency under waterlogging stress. Moreover, ALA pretreatment significantly increased activities of leaf superoxide dismutase (SOD) and peroxidase (POD), root vigor, and activities of root alcohol dehydrogenase (ADH), and lactate dehydrogenase (LDH), indicating ALA also significantly improves antioxidant ability and root function of fig plants under waterlogging stress. Taken together, ALA pretreatment improves waterlogging tolerance of fig plants significantly, and the promoted root respiration, leaf photosynthesis, and antioxidant ability may contribute greatly to this improvement. Our data firstly shows that ALA can improve plant waterlogging tolerance. PMID:26789407

  5. An Extreme Case of Plant–Insect Codiversification: Figs and Fig-Pollinating Wasps

    PubMed Central

    Cruaud, Astrid; Rønsted, Nina; Chantarasuwan, Bhanumas; Chou, Lien Siang; Clement, Wendy L.; Couloux, Arnaud; Cousins, Benjamin; Genson, Gwenaëlle; Harrison, Rhett D.; Hanson, Paul E.; Hossaert-Mckey, Martine; Jabbour-Zahab, Roula; Jousselin, Emmanuelle; Kerdelhué, Carole; Kjellberg, Finn; Lopez-Vaamonde, Carlos; Peebles, John; Peng, Yan-Qiong; Pereira, Rodrigo Augusto Santinelo; Schramm, Tselil; Ubaidillah, Rosichon; van Noort, Simon; Weiblen, George D.; Yang, Da-Rong; Yodpinyanee, Anak; Libeskind-Hadas, Ran; Cook, James M.; Rasplus, Jean-Yves; Savolainen, Vincent

    2012-01-01

    It is thought that speciation in phytophagous insects is often due to colonization of novel host plants, because radiations of plant and insect lineages are typically asynchronous. Recent phylogenetic comparisons have supported this model of diversification for both insect herbivores and specialized pollinators. An exceptional case where contemporaneous plant–insect diversification might be expected is the obligate mutualism between fig trees (Ficus species, Moraceae) and their pollinating wasps (Agaonidae, Hymenoptera). The ubiquity and ecological significance of this mutualism in tropical and subtropical ecosystems has long intrigued biologists, but the systematic challenge posed by >750 interacting species pairs has hindered progress toward understanding its evolutionary history. In particular, taxon sampling and analytical tools have been insufficient for large-scale cophylogenetic analyses. Here, we sampled nearly 200 interacting pairs of fig and wasp species from across the globe. Two supermatrices were assembled: on an average, wasps had sequences from 77% of 6 genes (5.6 kb), figs had sequences from 60% of 5 genes (5.5 kb), and overall 850 new DNA sequences were generated for this study. We also developed a new analytical tool, Jane 2, for event-based phylogenetic reconciliation analysis of very large data sets. Separate Bayesian phylogenetic analyses for figs and fig wasps under relaxed molecular clock assumptions indicate Cretaceous diversification of crown groups and contemporaneous divergence for nearly half of all fig and pollinator lineages. Event-based cophylogenetic analyses further support the codiversification hypothesis. Biogeographic analyses indicate that the present-day distribution of fig and pollinator lineages is consistent with a Eurasian origin and subsequent dispersal, rather than with Gondwanan vicariance. Overall, our findings indicate that the fig-pollinator mutualism represents an extreme case among plant–insect interactions of

  6. Images of an Activated Asteroid

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2016-08-01

    In late April of this year, asteroid P/2016 G1 (PANSTARRS) was discovered streaking through space, a tail of dust extending behind it. What caused this asteroids dust activity?Asteroid or Comet?Images of asteroid P/2016 G1 at three different times: late April, late May, and mid June. The arrow in the center panel points out an asymmetric feature that can be explained if the asteroid initially ejected material in a single direction, perhaps due to an impact. [Moreno et al. 2016]Asteroid P/2016 G1 is an interesting case: though it has the orbital elements of a main-belt asteroid it orbits at just under three times the EarthSun distance, with an eccentricity of e ~ 0.21 its appearance is closer to that of a comet, with a dust tail extending 20 behind it.To better understand the nature and cause of this unusual asteroids activity, a team led by Fernando Moreno (Institute of Astrophysics of Andalusia, in Spain) performed deep observations of P/2016 G1 shortly after its discovery. The team used the 10.4-meter Great Canary Telescope to image the asteroid over the span of roughly a month and a half.A Closer Look at P/2016 G1P/2016 G1 lies in the inner region of the main asteroid belt, so it is unlikely to have any ices that suddenly sublimated, causing the outburst. Instead, Moreno and collaborators suggest that the asteroids tail may have been caused by an impact that disrupted the parent body.To test this idea, the team used computer simulations to model their observations of P/2016 G1s dust tail. Based on their models, they demonstrate that the asteroid was likely activated on February 10 2016 roughly 350 days before it reached perihelion in its orbit and its activity was a short-duration event, lasting only ~24 days. The teams models indicate that over these 24 days, the asteroid lost around 20 million kilograms of dust, and at its maximum activity level, it was ejecting around 8 kg/s!Comparison of the observation from late May (panel a) and two models: one in which

  7. Fueling and imaging brain activation

    PubMed Central

    Dienel, Gerald A

    2012-01-01

    Metabolic signals are used for imaging and spectroscopic studies of brain function and disease and to elucidate the cellular basis of neuroenergetics. The major fuel for activated neurons and the models for neuron–astrocyte interactions have been controversial because discordant results are obtained in different experimental systems, some of which do not correspond to adult brain. In rats, the infrastructure to support the high energetic demands of adult brain is acquired during postnatal development and matures after weaning. The brain's capacity to supply and metabolize glucose and oxygen exceeds demand over a wide range of rates, and the hyperaemic response to functional activation is rapid. Oxidative metabolism provides most ATP, but glycolysis is frequently preferentially up-regulated during activation. Underestimation of glucose utilization rates with labelled glucose arises from increased lactate production, lactate diffusion via transporters and astrocytic gap junctions, and lactate release to blood and perivascular drainage. Increased pentose shunt pathway flux also causes label loss from C1 of glucose. Glucose analogues are used to assay cellular activities, but interpretation of results is uncertain due to insufficient characterization of transport and phosphorylation kinetics. Brain activation in subjects with low blood-lactate levels causes a brain-to-blood lactate gradient, with rapid lactate release. In contrast, lactate flooding of brain during physical activity or infusion provides an opportunistic, supplemental fuel. Available evidence indicates that lactate shuttling coupled to its local oxidation during activation is a small fraction of glucose oxidation. Developmental, experimental, and physiological context is critical for interpretation of metabolic studies in terms of theoretical models. PMID:22612861

  8. Fueling and imaging brain activation.

    PubMed

    Dienel, Gerald A

    2012-01-01

    Metabolic signals are used for imaging and spectroscopic studies of brain function and disease and to elucidate the cellular basis of neuroenergetics. The major fuel for activated neurons and the models for neuron-astrocyte interactions have been controversial because discordant results are obtained in different experimental systems, some of which do not correspond to adult brain. In rats, the infrastructure to support the high energetic demands of adult brain is acquired during postnatal development and matures after weaning. The brain's capacity to supply and metabolize glucose and oxygen exceeds demand over a wide range of rates, and the hyperaemic response to functional activation is rapid. Oxidative metabolism provides most ATP, but glycolysis is frequently preferentially up-regulated during activation. Underestimation of glucose utilization rates with labelled glucose arises from increased lactate production, lactate diffusion via transporters and astrocytic gap junctions, and lactate release to blood and perivascular drainage. Increased pentose shunt pathway flux also causes label loss from C1 of glucose. Glucose analogues are used to assay cellular activities, but interpretation of results is uncertain due to insufficient characterization of transport and phosphorylation kinetics. Brain activation in subjects with low blood-lactate levels causes a brain-to-blood lactate gradient, with rapid lactate release. In contrast, lactate flooding of brain during physical activity or infusion provides an opportunistic, supplemental fuel. Available evidence indicates that lactate shuttling coupled to its local oxidation during activation is a small fraction of glucose oxidation. Developmental, experimental, and physiological context is critical for interpretation of metabolic studies in terms of theoretical models. PMID:22612861

  9. Echo-planar magnetic resonance imaging studies of frontal cortex activation during word generation in humans.

    PubMed Central

    McCarthy, G; Blamire, A M; Rothman, D L; Gruetter, R; Shulman, R G

    1993-01-01

    Nine subjects were studied by high-speed magnetic resonance imaging while performing language-based tasks. Subjects were asked either to repeat or to generate verbs associated with nouns read by an experimenter while magnetic resonance images were obtained of the left inferior frontal lobe. The echo-planar imaging sequence was used with a gradient echo time of 70 ms to give an apparent transverse relaxation time weighting (T2* that is sensitive to local hemoglobin levels. Images were acquired every 3 s (repetition time) in series of 32. In plane resolution was 6 x 4.5 mm and slice thickness was 10 mm. An increase in signal accompanied performance of the tasks, with significantly more activation for verb generation than for repeating. The activation effect occurred within 3 s after task onset and could be observed in single images from individual subjects. The primary focus of activation appeared in gray matter along a sulcus anterior to the lateral sulcus that included the anterior insula, Brodmann's area 47, and extending to area 10. Little or no activation of this region was found for a passive listening, covert generation, or mouth-movement control tasks. Significant activation was also found for a homologous region in the right frontal cortex but not for control regions in calcarine cortex. These results are consistent with prior studies that have used positron emission tomography imaging with 15O-labeled water as a blood flow tracer. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 PMID:8506340

  10. Prevalence and genetic diversity of fig mosaic virus isolates infecting fig tree in Iran.

    PubMed

    Danesh-Amuz, S; Rakhshandehroo, F; Rezaee, S

    2014-01-01

    Commercial and outdoor fig orchards in four Iranian provinces were surveyed for the incidence of fig mosaic virus (FMV), fig leaf mottle associated virus 2 (FLMaV-2) and fig mild mottle associated virus (FMMaV) from March 2011 to October 2012. A total of 350 asymptomatic and symptomatic fig samples were collected and tested by dot-immunobinding assay (DIBA) for the fig mosaic disease (FMD) using a polyclonal antiserum. According to DIBA results, FMD was present in 73% of the collected symptomatic samples from all visited regions. Samples with positive reactions in DIBA were then analyzed by RT-PCR using with specific primers. PCR results showed that about 14.8% of the FMD-positive samples from three inspected provinces are infected with at least one virus. FMV was the most widely spread virus (14%) followed by FLMaV-2 (1.5%), whereas FMMaV was not found. Phylogenetic analysis of the glycoprotein nucleotide and amino acid sequences of known FMV isolates showed two independent groups with high bootstrap values, with all Iranian isolates distinctly clustered in group I, subgroup IA beside those reported in Turkey. Nucleotide diversity was high within but low between different selected geographic regions and except for Europe, nucleotide distance within geographic regions was low. Statistical analyses indicated a correlation between the genetic structure of the FMV isolates and the geographical origin of isolation. Our analyses suggested that the FMV population is in a state of increase following a bottleneck or founder event in Iran. PMID:25283859

  11. Characterization of fig operon mutants of Francisella novicida U112

    PubMed Central

    Kiss, Katalin; Liu, Wei; Huntley, Jason F.; Norgard, Michael V.; Hansen, Eric J.

    2009-01-01

    Francisella species secrete a polycarboxylate siderophore that resembles rhizoferrin to acquire ferric iron. Several of the Francisella siderophore synthesis genes are contained in a Fur-regulated operon (designated fig or fsl) comprised of at least seven open reading frames (ORFs) including fur. Reverse transcriptase-PCR showed transcriptional linkage between figD and figE and between figE and figF. Mutations were constructed in four of these ORFs (figB, figC, figD, and figE) in F. novicida U112. All four of these new mutants and a F. novicida figA mutant grew at rates comparable to that of wild-type under iron-replete conditions but growth of all five mutants was stunted in iron-limiting media. When ferric rhizoferrin was added to the iron-limited media, growth of the figA, figB, figC, and figD mutants was restored to levels similar to those obtained in iron-replete media. However, this exogenously added siderophore could not rescue the figE mutant. When Chrome Azurol S assays were used to measure siderophore production, the figA, figB, and figC mutants were markedly deficient in their ability to synthesize siderophore whereas the figD and figE mutants produced siderophore at levels equivalent to the wild-type parent strain. PMID:18564336

  12. A trophic cascade induced by predatory ants in a fig-fig wasp mutualism.

    PubMed

    Wang, Bo; Geng, Xiang-Zong; Ma, Li-Bin; Cook, James M; Wang, Rui-Wu

    2014-09-01

    A trophic cascade occurs when predators directly decrease the densities, or change the behaviour, of herbivores and thus indirectly increase plant productivity. The predator-herbivore-plant context is well known, but some predators attack species beneficial to plants (e.g. pollinators) and/or enemies of herbivores (e.g. parasites), and their role in the dynamics of mutualisms remains largely unexplored. We surveyed the predatory ant species and studied predation by the dominant ant species, the weaver ant Oecophylla smaragdina, associated with the fig tree Ficus racemosa in southwest China. We then tested the effects of weaver ants on the oviposition behaviour of pollinating and non-pollinating fig wasps in an ant-exclusion experiment. The effects of weaver ants on fig wasp community structure and fig seed production were then compared between trees with and without O. smaragdina. Oecophylla smaragdina captured more non-pollinating wasps (Platyneura mayri) than pollinators as the insects arrived to lay eggs. When ants were excluded, more non-pollinators laid eggs into figs and fewer pollinators entered figs. Furthermore, trees with O. smaragdina produced more pollinator offspring and fewer non-pollinator offspring, shifting the community structure significantly. In addition, F. racemosa produced significantly more seeds on trees inhabited by weaver ants. Oecophylla smaragdina predation reverses the dominance of the two commonest wasp species at the egg-laying stage and favours the pollinators. This behavioural pattern is mirrored by wasp offspring production, with pollinators' offspring dominating figs produced by trees inhabited by weaver ants, and offspring of the non-pollinator P. mayri most abundant in figs on trees inhabited by other ants. Overall, our results suggest that predation by weaver ants limits the success of the non-pollinating P. mayri and therefore indirectly benefits the mutualism by increasing the reproductive success of both the

  13. Hinode Captures Images of Solar Active Region

    NASA Video Gallery

    In these images, Hinode's Solar Optical Telescope (SOT) zoomed in on AR 11263 on August 4, 2011, five days before the active region produced the largest flare of this cycle, an X6.9. We show images...

  14. Discriminative host sanction together with relatedness promote the cooperation in fig/fig wasp mutualism.

    PubMed

    Wang, Rui-Wu; Sun, Bao-Fa; Yang, Yan

    2015-07-01

    Sanctioning or punishing is regarded as one of the most important dynamics in the evolution of cooperation. However, it has not been empirically examined yet whether or not such enforcement selection by sanctioning or punishing and classical theories like kin or reciprocity selection are separate mechanisms contributing to the evolution of cooperation. In addition, it remains largely unclear what factors determine the intensity or effectiveness of sanction. Here, we show that in the obligate, interspecific cooperation between figs and fig wasps, the hosted figs can discriminatively sanction cheating individuals by decreasing the offspring development ratio. Concurrently, the figs can reward the cooperative pollinators with a higher offspring development ratio. This sanction intensity and effectiveness largely depend on how closely the host and symbiont are related either in terms of reciprocity exchange or genetic similarity as measured by the reciprocal of the foundress number. Our results imply that in asymmetric systems, symbionts might be forced to evolve to be cooperative or even altruistic through discriminative sanction against the noncooperative symbiont and reward to the cooperative symbiont by the host (i.e. through a game of 'carrot and stick'). PMID:25661043

  15. Submillimeter Confocal Imaging Active Module

    NASA Technical Reports Server (NTRS)

    Hong, John; Mehdi, Imran; Siegel, Peter; Chattopadhyay, Goutam; Cwik, Thomas; Rowell, Mark; Hacker, John

    2009-01-01

    The term submillimeter confocal imaging active module (SCIAM) denotes a proposed airborne coherent imaging radar system that would be suitable for use in reconnaissance, surveillance, and navigation. The development of the SCIAM would include utilization and extension of recent achievements in monolithic microwave integrated circuits capable of operating at frequencies up to and beyond a nominal radio frequency of 340 GHz. Because the SCIAM would be primarily down-looking (in contradistinction to primarily side-looking), it could be useful for imaging shorter objects located between taller ones (for example, objects on streets between buildings). The SCIAM would utilize a confocal geometry to obtain high cross-track resolution, and would be amenable to synthetic-aperture processing of its output to obtain high along-track resolution. The SCIAM (see figure) would include multiple (two in the initial version) antenna apertures, separated from each other by a cross-track baseline of suitable length (e.g., 1.6 m). These apertures would both transmit the illuminating radar pulses and receive the returns. A common reference oscillator would generate a signal at a controllable frequency of (340 GHz + (Delta)f)/N, where (Delta)f is an instantaneous swept frequency difference and N is an integer. The output of this oscillator would be fed to a frequency- multiplier-and-power-amplifier module to obtain a signal, at 340 GHz + (Delta)f, that would serve as both the carrier signal for generating the transmitted pulses and a local-oscillator (LO) signal for a receiver associated with each antenna aperture. Because duplexers in the form of circulators or transmit/receive (T/R) switches would be lossy and extremely difficult to implement, the antenna apertures would be designed according to a spatial-diplexing scheme, in which signals would be coupled in and out via separate, adjacent transmitting and receiving feed horns. This scheme would cause the transmitted and received beams

  16. 21 CFR 145.131 - Artificially sweetened canned figs.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Artificially sweetened canned figs. 145.131... § 145.131 Artificially sweetened canned figs. (a) Artificially sweetened canned figs is the food which conforms to the definition and standard of identity prescribed for canned figs by § 145.130, except that...

  17. 21 CFR 145.131 - Artificially sweetened canned figs.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Artificially sweetened canned figs. 145.131... § 145.131 Artificially sweetened canned figs. (a) Artificially sweetened canned figs is the food which conforms to the definition and standard of identity prescribed for canned figs by § 145.130, except that...

  18. 21 CFR 145.131 - Artificially sweetened canned figs.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Artificially sweetened canned figs. 145.131... § 145.131 Artificially sweetened canned figs. (a) Artificially sweetened canned figs is the food which conforms to the definition and standard of identity prescribed for canned figs by § 145.130, except that...

  19. 7 CFR 457.110 - Fig crop insurance provisions.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 6 2013-01-01 2013-01-01 false Fig crop insurance provisions. 457.110 Section 457.110..., DEPARTMENT OF AGRICULTURE COMMON CROP INSURANCE REGULATIONS § 457.110 Fig crop insurance provisions. The Fig... Department of Agriculture Federal Crop Insurance Corporation Fig Crop Provisions If a conflict exists...

  20. 7 CFR 457.110 - Fig crop insurance provisions.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 6 2012-01-01 2012-01-01 false Fig crop insurance provisions. 457.110 Section 457.110..., DEPARTMENT OF AGRICULTURE COMMON CROP INSURANCE REGULATIONS § 457.110 Fig crop insurance provisions. The Fig... Department of Agriculture Federal Crop Insurance Corporation Fig Crop Provisions If a conflict exists...

  1. 21 CFR 145.131 - Artificially sweetened canned figs.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Artificially sweetened canned figs. 145.131... § 145.131 Artificially sweetened canned figs. (a) Artificially sweetened canned figs is the food which conforms to the definition and standard of identity prescribed for canned figs by § 145.130, except that...

  2. 21 CFR 145.131 - Artificially sweetened canned figs.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Artificially sweetened canned figs. 145.131... § 145.131 Artificially sweetened canned figs. (a) Artificially sweetened canned figs is the food which conforms to the definition and standard of identity prescribed for canned figs by § 145.130, except that...

  3. 7 CFR 457.110 - Fig crop insurance provisions.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 6 2014-01-01 2014-01-01 false Fig crop insurance provisions. 457.110 Section 457.110..., DEPARTMENT OF AGRICULTURE COMMON CROP INSURANCE REGULATIONS § 457.110 Fig crop insurance provisions. The Fig... Department of Agriculture Federal Crop Insurance Corporation Fig Crop Provisions If a conflict exists...

  4. Active Nuclear Material Detection and Imaging

    SciTech Connect

    Daren Norman; James Jones; KevinHaskell; Peter E. Vanmier; Leon Forman

    2005-10-01

    An experimental evaluation has been conducted to assess the operational performance of a coded-aperture, thermal neutron imaging system and its detection and imaging capability for shielded nuclear material in pulsed photonuclear environments. This evaluation used an imaging system developed by Brookhaven National Laboratory. The active photonuclear environment was produced by an operationallyflexible, Idaho National Laboratory (INL) pulsed electron accelerator. The neutron environments were monitored using INL photonuclear neutron detectors. Results include experimental images, operational imaging system assessments and recommendations that would enhance nuclear material detection and imaging performance.

  5. Reactivation of Lysosomal Ca2+ Efflux Rescues Abnormal Lysosomal Storage in FIG4-Deficient Cells.

    PubMed

    Zou, Jianlong; Hu, Bo; Arpag, Sezgi; Yan, Qing; Hamilton, Audra; Zeng, Yuan-Shan; Vanoye, Carlos G; Li, Jun

    2015-04-29

    Loss of function of FIG4 leads to Charcot-Marie-Tooth disease Type 4J, Yunis-Varon syndrome, or an epilepsy syndrome. FIG4 is a phosphatase with its catalytic specificity toward 5'-phosphate of phosphatidylinositol-3,5-diphosphate (PI3,5P2). However, the loss of FIG4 decreases PI3,5P2 levels likely due to FIG4's dominant effect in scaffolding a PI3,5P2 synthetic protein complex. At the cellular level, all these diseases share similar pathology with abnormal lysosomal storage and neuronal degeneration. Mice with no FIG4 expression (Fig4(-/-)) recapitulate the pathology in humans with FIG4 deficiency. Using a flow cytometry technique that rapidly quantifies lysosome sizes, we detected an impaired lysosomal fission, but normal fusion, in Fig4(-/-) cells. The fission defect was associated with a robust increase of intralysosomal Ca(2+) in Fig4(-/-) cells, including FIG4-deficient neurons. This finding was consistent with a suppressed Ca(2+) efflux of lysosomes because the endogenous ligand of lysosomal Ca(2+) channel TRPML1 is PI3,5P2 that is deficient in Fig4(-/-) cells. We reactivated the TRPML1 channels by application of TRPML1 synthetic ligand, ML-SA1. This treatment reduced the intralysosomal Ca(2+) level and rescued abnormal lysosomal storage in Fig4(-/-) culture cells and ex vivo DRGs. Furthermore, we found that the suppressed Ca(2+) efflux in Fig4(-/-) culture cells and Fig4(-/-) mouse brains profoundly downregulated the expression/activity of dynamin-1, a GTPase known to scissor organelle membranes during fission. This downregulation made dynamin-1 unavailable for lysosomal fission. Together, our study revealed a novel mechanism explaining abnormal lysosomal storage in FIG4 deficiency. Synthetic ligands of the TRPML1 may become a potential therapy against diseases with FIG4 deficiency. PMID:25926456

  6. Hyperspectral image segmentation using active contours

    NASA Astrophysics Data System (ADS)

    Lee, Cheolha P.; Snyder, Wesley E.

    2004-08-01

    Multispectral or hyperspectral image processing has been studied as a possible approach to automatic target recognition (ATR). Hundreds of spectral bands may provide high data redundancy, compensating the low contrast in medium wavelength infrared (MWIR) and long wavelength infrared (LWIR) images. Thus, the combination of spectral (image intensity) and spatial (geometric feature) information analysis could produce a substantial improvement. Active contours provide segments with continuous boundaries, while edge detectors based on local filtering often provide discontinuous boundaries. The segmentation by active contours depends on geometric feature of the object as well as image intensity. However, the application of active contours to multispectral images has been limited to the cases of simply textured images with low number of frames. This paper presents a supervised active contour model, which is applicable to vector-valued images with non-homogeneous regions and high number of frames. In the training stage, histogram models of target classes are estimated from sample vector-pixels. In the test stage, contours are evolved based on two different metrics: the histogram models of the corresponding segments and the histogram models estimated from sample target vector-pixels. The proposed segmentation method integrates segmentation and model-based pattern matching using supervised segmentation and multi-phase active contour model, while traditional methods apply pattern matching only after the segmentation. The proposed algorithm is implemented with both synthetic and real multispectral images, and shows desirable segmentation and classification results even in images with non-homogeneous regions.

  7. Physical activity - preventive medicine (image)

    MedlinePlus

    Physical activity contributes to health by reducing the heart rate, decreasing the risk for cardiovascular disease, and reducing ... loss that is associated with age and osteoporosis. Physical activity also helps the body use calories more efficiently, ...

  8. Female figs as traps: Their impact on the dynamics of an experimental fig tree-pollinator-parasitoid community

    NASA Astrophysics Data System (ADS)

    Suleman, Nazia; Sait, Steve; Compton, Stephen G.

    2015-01-01

    Interactions between fig trees (Ficus) and their pollinating fig wasps (Agaonidae) result in both a highly species-specific nursery mutualism and mutual exploitation. Around half of the 800 or so fig tree species are functionally dioecious. Figs on male plants produce pollen and fig wasp offspring, whereas figs on female plants produce only seeds. Figs on female plants are traps for pollinators. The fig wasps enter the female figs to oviposit, but lose their wings on entry and are then prevented from oviposition by the long styles that characterise the flowers in female figs. Continuation of the mutualism depends on the pollinators' failure to distinguish between male and female figs before entry. Female plants may also have a negative impact on the parasitoid fig wasps that feed on pollinators, if they are also attracted to female figs. We used glasshouse populations of figs (with and without female plants), pollinators and parasitoids to infer the impact of female figs on fig wasp dynamics. Cyclic population fluctuations were present in both species. Female plants appeared to dampen the amplitudes of pollinator population cycles, and parasitoid populations may become less tightly coupled with host populations, but the presence of female figs did not reduce parasitism rates, nor parasitoid and pollinator densities, and only parasitoid sex ratios were affected. Our glasshouse experimental design was likely to favour the impact of female figs on the wasp populations, which suggests that female plants in the field are unlikely to have a major negative impact on their pollinators, despite being a major mortality factor.

  9. Active vs. inactive muscle (image)

    MedlinePlus

    ... may lose 20 to 40 percent of their muscle -- and, along with it, their strength -- as they ... have found that a major reason people lose muscle is because they stop doing everyday activities that ...

  10. Molecular Imaging with SERS-Active Nanoparticles

    PubMed Central

    Zhang, Yin; Hong, Hao; Myklejord, Duane V.; Cai, Weibo

    2011-01-01

    Lead-in Raman spectroscopy has been explored for various biomedical applications (e.g. cancer diagnosis) because it can provide detailed information on the chemical composition of cells and tissues. For imaging applications, several variations of Raman spectroscopy have been developed to enhance its sensitivity. To date, a wide variety of molecular targets and biological events have been investigated using surface-enhanced Raman scattering (SERS)-active nanoparticles. The superb multiplexing capability of SERS-based Raman imaging, already successfully demonstrated in live animals, can be extremely powerful in future research where different agents can be attached to different Raman tags to enable the simultaneous interrogation of multiple biological events. Over the last several years, molecular imaging with SERS-active nanoparticles has advanced significantly and many pivotal proof-of-principle experiments have been successfully carried out. It is expected that SERS-based imaging will continue to be a dynamic research field over the next decade. PMID:21932216

  11. Seasonality of Leaf and Fig Production in Ficus squamosa, a Fig Tree with Seeds Dispersed by Water

    PubMed Central

    Pothasin, Pornwiwan; Compton, Stephen G.; Wangpakapattanawong, Prasit

    2016-01-01

    The phenology of plants reflects selection generated by seasonal climatic factors and interactions with other plants and animals, within constraints imposed by their phylogenetic history. Fig trees (Ficus) need to produce figs year-round to support their short-lived fig wasp pollinators, but this requirement is partially de-coupled in dioecious species, where female trees only develop seeds, not pollinator offspring. This allows female trees to concentrate seed production at more favorable times of the year. Ficus squamosa is a riparian species whose dispersal is mainly by water, rather than animals. Seeds can float and travel in long distances. We recorded the leaf and reproductive phenology of 174 individuals for three years in Chiang Mai, Northern Thailand. New leaves were produced throughout the year. Fig production occurred year-round, but with large seasonal variations that correlated with temperature and rainfall. Female and male trees initiated maximal fig crops at different times, with production in female trees confined mainly to the rainy season and male figs concentrating fig production in the preceding months, but also often bearing figs continually. Ficus squamosa concentrates seed production by female plants at times when water levels are high, favouring dispersal by water, and asynchronous flowering within male trees allow fig wasps to cycle there, providing them with potential benefits by maintaining pollinators for times when female figs become available to pollinate. PMID:27010540

  12. Seasonality of Leaf and Fig Production in Ficus squamosa, a Fig Tree with Seeds Dispersed by Water.

    PubMed

    Pothasin, Pornwiwan; Compton, Stephen G; Wangpakapattanawong, Prasit

    2016-01-01

    The phenology of plants reflects selection generated by seasonal climatic factors and interactions with other plants and animals, within constraints imposed by their phylogenetic history. Fig trees (Ficus) need to produce figs year-round to support their short-lived fig wasp pollinators, but this requirement is partially de-coupled in dioecious species, where female trees only develop seeds, not pollinator offspring. This allows female trees to concentrate seed production at more favorable times of the year. Ficus squamosa is a riparian species whose dispersal is mainly by water, rather than animals. Seeds can float and travel in long distances. We recorded the leaf and reproductive phenology of 174 individuals for three years in Chiang Mai, Northern Thailand. New leaves were produced throughout the year. Fig production occurred year-round, but with large seasonal variations that correlated with temperature and rainfall. Female and male trees initiated maximal fig crops at different times, with production in female trees confined mainly to the rainy season and male figs concentrating fig production in the preceding months, but also often bearing figs continually. Ficus squamosa concentrates seed production by female plants at times when water levels are high, favouring dispersal by water, and asynchronous flowering within male trees allow fig wasps to cycle there, providing them with potential benefits by maintaining pollinators for times when female figs become available to pollinate. PMID:27010540

  13. See around the corner using active imaging

    NASA Astrophysics Data System (ADS)

    Steinvall, Ove; Elmqvist, Magnus; Larsson, Håkan

    2011-11-01

    This paper investigates the prospects of "seeing around the corner" using active imaging. A monostatic active imaging system offers interesting capabilities in the presence of glossy reflecting objects. Examples of such surfaces are windows in buildings and cars, calm water, signs and vehicle surfaces. During daylight it might well be possible to use mirrorlike reflection by the naked eye or a CCD camera for non-line of sight imaging. However the advantage with active imaging is that one controls the illumination. This will not only allow for low light and night utilization but also for use in cases where the sun or other interfering lights limit the non-line of sight imaging possibility. The range resolution obtained by time gating will reduce disturbing direct reflections and allow simultaneous view in several directions using range discrimination. Measurements and theoretical considerations in this report support the idea of using laser to "see around the corner". Examples of images and reflectivity measurements will be presented together with examples of potential system applications.

  14. Relative investment in egg load and poison sac in fig wasps: Implications for physiological mechanisms underlying seed and wasp production in figs

    NASA Astrophysics Data System (ADS)

    Martinson, Ellen O.; Jandér, K. Charlotte; Peng, Yan-Qiong; Chen, Huan-Huan; Machado, Carlos A.; Arnold, A. Elizabeth; Herre, Edward Allen

    2014-05-01

    Fig pollinating wasps and most non-pollinator wasps apply secretions from their poison sacs into oviposited flowers that appear necessary to the formation of the galls that their developing offspring consume. Thus, both eggs and poison sac secretions appear to be essential for wasp reproduction, but the relative investment in each is unknown. We measured relative investment in poison sac and egg production in pollinating and non-pollinating wasps associated with seven species of monoecious Panamanian figs representing both active and passive pollination syndromes. We then collected similar data for four fig hosts in China, where some wasp species in the genus Eupristina have lost the ability to pollinate ("cheaters"). All wasps examined possessed large poison sacs, and we found a strong positive correlation between poison sac size and absolute egg production. In the Panamanian species, the relative poison sac to egg investment was highest in the externally ovipositing non-pollinator wasps, followed by active pollinators, then by passive pollinators. Further, pollinator wasps of fig species with demonstrated host sanctions against "cheating" wasps showed higher investment in the poison sac than wasps of species without sanctions. In the Chinese samples, relative investment in the poison sac was indistinguishable between pollinators and "cheaters" associated with the same fig species. We suggest that higher relative investment in poison sac across fig wasp species reflects higher relative difficulty in initiating formation of galls and subsequently obtaining resources from the fig. We discuss the implications for the stability of the fig-wasp mutualism, and for the ability of non-pollinators to exploit this mutualism.

  15. Scalable histopathological image analysis via active learning.

    PubMed

    Zhu, Yan; Zhang, Shaoting; Liu, Wei; Metaxas, Dimitris N

    2014-01-01

    Training an effective and scalable system for medical image analysis usually requires a large amount of labeled data, which incurs a tremendous annotation burden for pathologists. Recent progress in active learning can alleviate this issue, leading to a great reduction on the labeling cost without sacrificing the predicting accuracy too much. However, most existing active learning methods disregard the "structured information" that may exist in medical images (e.g., data from individual patients), and make a simplifying assumption that unlabeled data is independently and identically distributed. Both may not be suitable for real-world medical images. In this paper, we propose a novel batch-mode active learning method which explores and leverages such structured information in annotations of medical images to enforce diversity among the selected data, therefore maximizing the information gain. We formulate the active learning problem as an adaptive submodular function maximization problem subject to a partition matroid constraint, and further present an efficient greedy algorithm to achieve a good solution with a theoretically proven bound. We demonstrate the efficacy of our algorithm on thousands of histopathological images of breast microscopic tissues. PMID:25320821

  16. Genetic structure and differentiation in cultivated fig (Ficus carica L.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One hundred ninety-four germplasm accessions of fig representing the four fig types, Common, Smyrna, San Pedro, and Caprifig were analyzed for genetic diversity, structure, and differentiation using genetic polymorphism at 17 microsatellite loci. The collection showed considerable polymorphism with ...

  17. Rain-fed fig yield as affected by rainfall distribution

    NASA Astrophysics Data System (ADS)

    Bagheri, Ensieh; Sepaskhah, Ali Reza

    2014-08-01

    Variable annual rainfall and its uneven distribution are the major uncontrolled inputs in rain-fed fig production and possibly the main cause of yield fluctuation in Istahban region of Fars Province, I.R. of Iran. This introduces a considerable risk in rain-fed fig production. The objective of this study was to find relationships between seasonal rainfall distribution and rain-fed fig production in Istahban region to determine the critical rainfall periods for rain-fed fig production and supplementary irrigation water application. Further, economic analysis for rain-fed fig production was considered in this region to control the risk of production. It is concluded that the monthly, seasonal and annual rainfall indices are able to show the effects of rainfall and its distribution on the rain-fed fig yield. Fig yield with frequent occurrence of 80 % is 374 kg ha-1. The internal rates of return for interest rate of 4, 8 and 12 % are 21, 58 and 146 %, respectively, that are economically feasible. It is concluded that the rainfall in spring especially in April and in December has negatively affected fig yield due to its interference with the life cycle of Blastophaga bees for pollination. Further, it is concluded that when the rainfall is limited, supplementary irrigation can be scheduled in March.

  18. 7 CFR 457.110 - Fig crop insurance provisions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... or more crops are planted in any form of alternating or mixed pattern. Manufacturing grade production— Production that meets the minimum grade standards and is defined as “manufacturing grade” by the Marketing...— Figs that grade manufacturing grade or better in accordance with the Marketing Order for Dried Figs,...

  19. 7 CFR 457.110 - Fig crop insurance provisions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... or more crops are planted in any form of alternating or mixed pattern. Manufacturing grade production— Production that meets the minimum grade standards and is defined as “manufacturing grade” by the Marketing...— Figs that grade manufacturing grade or better in accordance with the Marketing Order for Dried Figs,...

  20. Exchange of hosts: can agaonid fig wasps reproduce successfully in the figs of non-host Ficus?

    NASA Astrophysics Data System (ADS)

    Yang, Pei; Li, Zongbo; Peng, Yanqiong; Yang, Darong

    2012-03-01

    In the obligate mutualism between figs ( Ficus) and their specific pollinators (Chalcidoidea, Agaonidae), each species of fig wasp typically reproduces in figs of a single host species. Host specificity is maintained largely because pollinators are attracted to tree-specific volatiles released from their host figs, but whether the wasps can reproduce if they enter figs of non-host species is unclear. We investigated the reproductive success of Ceratosolen emarginatus (associated with Ficus auriculata) and Ceratosolen sp. (associated with F. hainanensis) in atypical hosts by experimentally introducing foundresses into host and non-host figs. F. auriculata figs entered by Ceratosolen sp. were more likely to abort than if entered by C. emarginatus, but abortion of F. hainanensis figs was not affected by pollinator species. Single C. emarginatus foundresses produced more but smaller offspring in F. hainanensis than in their normal host. Conversely Ceratosolen sp. produced fewer but larger offspring in F. auriculata than in their normal host, probably as a result of having longer to develop. Mean style length differences, relative to the lengths of the wasps' ovipositors, may have dictated the number of offspring produced, with oviposition made easier by the shorter styles in F. hainanensis figs. Our results imply that, in addition to morphological constraints and tree-specific volatiles, reduced reproductive success in atypical hosts can be another factor maintaining host specificity, but for other species only behavioural changes are required for host switching to occur.

  1. Imaging CREB Activation in Living Cells*

    PubMed Central

    Friedrich, Michael W.; Aramuni, Gayane; Mank, Marco; Mackinnon, Jonathan A. G.; Griesbeck, Oliver

    2010-01-01

    The Ca2+- and cAMP-responsive element-binding protein (CREB) and the related ATF-1 and CREM are stimulus-inducible transcription factors that link certain forms of cellular activity to changes in gene expression. They are attributed to complex integrative activation characteristics, but current biochemical technology does not allow dynamic imaging of CREB activation in single cells. Using fluorescence resonance energy transfer between mutants of green fluorescent protein we here develop a signal-optimized genetically encoded indicator that enables imaging activation of CREB due to phosphorylation of the critical serine 133. The indicator of CREB activation due to phosphorylation (ICAP) was used to investigate the role of the scaffold and anchoring protein AKAP79/150 in regulating signal pathways converging on CREB. We show that disruption of AKAP79/150-mediated protein kinase A anchoring or knock-down of AKAP150 dramatically reduces the ability of protein kinase A to activate CREB. In contrast, AKAP79/150 regulation of CREB via L-type channels may only have minor importance. ICAP allows dynamic and reversible imaging in living cells and may become useful in studying molecular components and cell-type specificity of activity-dependent gene expression. PMID:20484048

  2. Active place recognition using image signatures

    NASA Astrophysics Data System (ADS)

    Engelson, Sean P.

    1992-11-01

    For reliable navigation, a mobile robot needs to be able to recognize where it is in the world. We previously described an efficient and effective image-based representation of perceptual information for place recognition. Each place is associated with a set of stored image signatures, each a matrix of numbers derived by evaluating some measurement functions over large blocks of pixels. One difficulty, though, is the large number of inherently ambiguous signatures which bloats the database and makes recognition more difficult. Furthermore, since small differences in orientation can produce very different images, reliable recognition requires many images. These problems can be ameliorated by using active methods to select the best signatures to use for the recognition. Two criteria for good images are distinctiveness (is the scene distinguishable from others?) and stability (how much do small viewpoint motions change image recognizability?). We formulate several heuristic distinctiveness metrics which are good predictors of real image distinctiveness. These functions are then used to direct the motion of the camera to find locally distinctive views for use in recognition. This method also produces some modicum of stability, since it uses a form of local optimization. We present the results of applying this method with a camera mounted on a pan-tilt platform.

  3. Active confocal imaging for visual prostheses

    PubMed Central

    Jung, Jae-Hyun; Aloni, Doron; Yitzhaky, Yitzhak; Peli, Eli

    2014-01-01

    There are encouraging advances in prosthetic vision for the blind, including retinal and cortical implants, and other “sensory substitution devices” that use tactile or electrical stimulation. However, they all have low resolution, limited visual field, and can display only few gray levels (limited dynamic range), severely restricting their utility. To overcome these limitations, image processing or the imaging system could emphasize objects of interest and suppress the background clutter. We propose an active confocal imaging system based on light-field technology that will enable a blind user of any visual prosthesis to efficiently scan, focus on, and “see” only an object of interest while suppressing interference from background clutter. The system captures three-dimensional scene information using a light-field sensor and displays only an in-focused plane with objects in it. After capturing a confocal image, a de-cluttering process removes the clutter based on blur difference. In preliminary experiments we verified the positive impact of confocal-based background clutter removal on recognition of objects in low resolution and limited dynamic range simulated phosphene images. Using a custom-made multiple-camera system, we confirmed that the concept of a confocal de-cluttered image can be realized effectively using light field imaging. PMID:25448710

  4. Active gated imaging in driver assistance system

    NASA Astrophysics Data System (ADS)

    Grauer, Yoav

    2014-04-01

    In this paper, we shall present the active gated imaging system (AGIS) in relation to the automotive field. AGIS is based on a fast-gated camera and pulsed illuminator, synchronized in the time domain to record images of a certain range of interest. A dedicated gated CMOS imager sensor and near infra-red (NIR) pulsed laser illuminator, is presented in this paper to provide active gated technology. In recent years, we have developed these key components and learned the system parameters, which are most beneficial to nighttime (in all weather conditions) driving in terms of field of view, illumination profile, resolution, and processing power. We shall present our approach of a camera-based advanced driver assistance systems (ADAS) named BrightEye™, which makes use of the AGIS technology in the automotive field.

  5. Active-imaging-based underwater navigation

    NASA Astrophysics Data System (ADS)

    Monnin, David; Schmitt, Gwenaël.; Fischer, Colin; Laurenzis, Martin; Christnacher, Frank

    2015-10-01

    Global navigation satellite systems (GNSS) are widely used for the localization and the navigation of unmanned and remotely operated vehicles (ROV). In contrast to ground or aerial vehicles, GNSS cannot be employed for autonomous underwater vehicles (AUV) without the use of a communication link to the water surface, since satellite signals cannot be received underwater. However, underwater autonomous navigation is still possible using self-localization methods which determines the relative location of an AUV with respect to a reference location using inertial measurement units (IMU), depth sensors and even sometimes radar or sonar imaging. As an alternative or a complementary solution to common underwater reckoning techniques, we present the first results of a feasibility study of an active-imaging-based localization method which uses a range-gated active-imaging system and can yield radiometric and odometric information even in turbid water.

  6. Active imaging system with Faraday filter

    DOEpatents

    Snyder, J.J.

    1993-04-13

    An active imaging system has a low to medium powered laser transmitter and receiver wherein the receiver includes a Faraday filter with an ultranarrow optical bandpass and a bare (nonintensified) CCD camera. The laser is locked in the vicinity of the passband of the Faraday filter. The system has high sensitivity to the laser illumination while eliminating solar background.

  7. Active imaging system with Faraday filter

    DOEpatents

    Snyder, James J.

    1993-01-01

    An active imaging system has a low to medium powered laser transmitter and receiver wherein the receiver includes a Faraday filter with an ultranarrow optical bandpass and a bare (nonintensified) CCD camera. The laser is locked in the vicinity of the passband of the Faraday filter. The system has high sensitivity to the laser illumination while eliminating solar background.

  8. Fig4 Deficiency: A Newly Emerged Lysosomal Storage Disorder?

    PubMed Central

    Martyn, Colin; Li, Jun

    2012-01-01

    FIG4 (Sac3 in mammals) is a 5’-phosphoinositide phosphatase that coordinates the turnover of phosphatidylinositol-3,5-bisphosphate (PI(3,5)P2), a very low abundance phosphoinositide. Deficiency of FIG4 severely affects the human and mouse nervous systems by causing two distinct forms of abnormal lysosomal storage. The first form occurs in spinal sensory neurons, where vacuolated endolysosomes accumulate in perinuclear regions. A second form occurs in cortical/spinal motor neurons and glia, in which enlarged endolysosomes become filled with electron dense materials in a manner indistinguishable from other lysosomal storage disorders. Humans with a deficiency of FIG4 (known as Charcot-Marie-Tooth disease type 4J or CMT4J) present with clinical and pathophysiological phenotypes indicative of spinal motor neuron degeneration and segmental demyelination. These findings reveal a signaling pathway involving FIG4 that appears to be important for lysosomal function. In this review, we discuss the biology of FIG4 and describe how the deficiency of FIG4 results in lysosomal phenotypes. We also discuss the implications of FIG4/PI(3,5)P2 signaling in understanding other lysosomal storage diseases, neuropathies, and acquired demyelinating diseases. PMID:23165282

  9. How chimpanzees integrate sensory information to select figs.

    PubMed

    Dominy, Nathaniel J; Yeakel, Justin D; Bhat, Uttam; Ramsden, Lawrence; Wrangham, Richard W; Lucas, Peter W

    2016-06-01

    Figs are keystone resources that sustain chimpanzees when preferred fruits are scarce. Many figs retain a green(ish) colour throughout development, a pattern that causes chimpanzees to evaluate edibility on the basis of achromatic accessory cues. Such behaviour is conspicuous because it entails a succession of discrete sensory assessments, including the deliberate palpation of individual figs, a task that requires advanced visuomotor control. These actions are strongly suggestive of domain-specific information processing and decision-making, and they call attention to a potential selective force on the origin of advanced manual prehension and digital dexterity during primate evolution. To explore this concept, we report on the foraging behaviours of chimpanzees and the spectral, chemical and mechanical properties of figs, with cutting tests revealing ease of fracture in the mouth. By integrating the ability of different sensory cues to predict fructose content in a Bayesian updating framework, we quantified the amount of information gained when a chimpanzee successively observes, palpates and bites the green figs of Ficus sansibarica. We found that the cue eliciting ingestion was not colour or size, but fig mechanics (including toughness estimates from wedge tests), which relays higher-quality information on fructose concentrations than colour vision. This result explains why chimpanzees evaluate green figs by palpation and dental incision, actions that could explain the adaptive origins of advanced manual prehension. PMID:27274803

  10. How chimpanzees integrate sensory information to select figs

    PubMed Central

    Yeakel, Justin D.; Bhat, Uttam; Ramsden, Lawrence; Wrangham, Richard W.; Lucas, Peter W.

    2016-01-01

    Figs are keystone resources that sustain chimpanzees when preferred fruits are scarce. Many figs retain a green(ish) colour throughout development, a pattern that causes chimpanzees to evaluate edibility on the basis of achromatic accessory cues. Such behaviour is conspicuous because it entails a succession of discrete sensory assessments, including the deliberate palpation of individual figs, a task that requires advanced visuomotor control. These actions are strongly suggestive of domain-specific information processing and decision-making, and they call attention to a potential selective force on the origin of advanced manual prehension and digital dexterity during primate evolution. To explore this concept, we report on the foraging behaviours of chimpanzees and the spectral, chemical and mechanical properties of figs, with cutting tests revealing ease of fracture in the mouth. By integrating the ability of different sensory cues to predict fructose content in a Bayesian updating framework, we quantified the amount of information gained when a chimpanzee successively observes, palpates and bites the green figs of Ficus sansibarica. We found that the cue eliciting ingestion was not colour or size, but fig mechanics (including toughness estimates from wedge tests), which relays higher-quality information on fructose concentrations than colour vision. This result explains why chimpanzees evaluate green figs by palpation and dental incision, actions that could explain the adaptive origins of advanced manual prehension. PMID:27274803

  11. Moving Your Sons to Safety: Galls Containing Male Fig Wasps Expand into the Centre of Figs, Away From Enemies

    PubMed Central

    Yu, Hui; Compton, Stephen G.

    2012-01-01

    Figs are the inflorescences of fig trees (Ficus spp., Moraceae). They are shaped like a hollow ball, lined on their inner surface by numerous tiny female flowers. Pollination is carried out by host-specific fig wasps (Agaonidae). Female pollinators enter the figs through a narrow entrance gate and once inside can walk around on a platform generated by the stigmas of the flowers. They lay their eggs into the ovules, via the stigmas and styles, and also gall the flowers, causing the ovules to expand and their pedicels to elongate. A single pollinator larva develops in each galled ovule. Numerous species of non-pollinating fig wasps (NPFW, belonging to other families of Chalcidoidea) also make use of galled ovules in the figs. Some initiate galls, others make use of pollinator-generated galls, killing pollinator larvae. Most NPFW oviposit from the outside of figs, making peripherally-located pollinator larvae more prone to attack. Style length variation is high among monoecious Ficus spp. and pollinators mainly oviposit into more centrally-located ovules, with shorter styles. Style length variation is lower in male (wasp-producing) figs of dioecious Ficus spp., making ovules equally vulnerable to attack by NPFW at the time that pollinators oviposit. We recorded the spatial distributions of galled ovules in mature male figs of the dioecious Ficus hirta in Southern China. The galls contained pollinators and three NPFW that kill them. Pollinators were concentrated in galls located towards the centre of the figs, NPFW towards the periphery. Due to greater pedicel elongation by male galls, male pollinators became located in more central galls than their females, and so were less likely to be attacked. This helps ensure that sufficient males survive, despite strongly female-biased sex ratios, and may be a consequence of the pollinator females laying mostly male eggs at the start of oviposition sequences. PMID:22295113

  12. Adjoint active surfaces for localization and imaging.

    PubMed

    Cook, Daniel A; Mueller, Martin Fritz; Fedele, Francesco; Yezzi, Anthony J

    2015-01-01

    This paper addresses the problem of localizing and segmenting regions embedded within a surrounding medium by characterizing their boundaries, as opposed to imaging the entirety of the volume. Active surfaces are used to directly reconstruct the shape of the region of interest. We describe the procedure for finding the optimal surface, which is computed iteratively via gradient descent that exploits the sensitivity of an error minimization functional to changes of the active surface. In doing so, we introduce the adjoint model to compute the sensitivity, and in this respect, the method shares common ground with several other disciplines, such as optimal control. Finally, we illustrate the proposed active surface technique in the framework of wave propagation governed by the scalar Helmholtz equation. Potential applications include electromagnetics, acoustics, geophysics, nondestructive testing, and medical imaging. PMID:25438311

  13. Host pollination mode and mutualist pollinator presence: net effect of internally ovipositing parasite in the fig-wasp mutualism

    NASA Astrophysics Data System (ADS)

    Zhang, Fengping; Peng, Yanqiong; Compton, Stephen G.; Zhao, Yi; Yang, Darong

    2009-04-01

    The Ficus-their specific pollinating fig wasps (Chalcidoidea, Agaonidae) interaction presents a striking example of mutualism. Figs also shelter numerous non-pollinating fig wasps (NPFW) that exploit the fig-pollinator mutualism. Only a few NPFW species can enter figs to oviposit, they do not belong to the pollinating lineage Agaonidae. The internally ovipositing non-agaonid fig wasps can efficiently pollinate the Ficus species that were passively pollinated. However, there is no study to focus on the net effect of these internally ovipositing non-agaonid wasps in actively pollinated Ficus species. By collecting the data of fig wasp community and conducting controlled experiments, our results showed that internally ovipositing Diaziella bizarrea cannot effectively pollinate Ficus glaberrima, an actively pollinated monoecious fig tree. Furthermore, D. bizarrea failed to reproduce if they were introduced into figs without Eupristina sp., the regular pollinator, as all the figs aborted. Furthermore, although D. bizarrea had no effect on seed production in shared figs, it significantly reduced the number of Eupristina sp. progeny emerging from them. Thus, our experimental evidence shows that reproduction in Diaziella depends on the presence of agaonid pollinators, and whether internally ovipositing parasites can act as pollinators depends on the host fig’s pollination mode (active or passive). Overall, this study and others suggest a relatively limited mutualistic role for internally ovipositing fig wasps from non-pollinator (non-Agaonidae) lineages.

  14. Polarimetric active imaging in dense fog

    NASA Astrophysics Data System (ADS)

    Bernier, Robert; Cao, Xiaoying; Tremblay, Grégoire; Roy, Gilles

    2015-10-01

    Operation under degraded visual environment (DVE) presents important strategic advantages. 3D mapping has been performed under DVE and good quality images have been obtained through DVE with active imaging systems. In these applications, the presence of fog clouds degrades the quality of the remotely sensed signal or even renders the operation totally impossible. In view of making the active imaging method more robust against dense fog, the use of polarimetry is herein studied. Spherical particles typical of fog do not depolarize incident polarized light in the backscattering (180°) direction. So, in principle, there should be less dazzling caused by aerosols for active imaging systems operating using the secondary polarization. However, strong depolarization still occurs at angles close to 180°. The greater the ratio of size to wavelength, the closer to 180° will the depolarization occur. When the cloud optical depth is small, the major scattering events seen by an active camera are the single backscattering events. However, when the optical depth of the cloud is higher than 1, multiple scattering becomes more important and causes depolarization due to the backscattering around 180°. The physics of this process will be discussed. Experimental results supporting the analysis will be presented. Those experimental results were obtained under controlled environment using the DRDC-Valcartier aerosol chamber. The experimental method herein proposed is based upon the use of ICCD range gated cameras wherein gate width and gate location may be varied on the fly. The optimal conditions for the use of these devices in view of obtaining the best image contrast are experimentally studied and reported in this paper.

  15. Imaging Active Urokinase Plasminogen Activator in Prostate Cancer

    PubMed Central

    LeBeau, Aaron M.; Sevillano, Natalia; Markham, Kate; Winter, Michael B.; Murphy, Stephanie T.; Hostetter, Daniel R.; West, James; Lowman, Henry; Craik, Charles S.; VanBrocklin, Henry F.

    2015-01-01

    The increased proteolytic activity of membrane-bound and secreted proteases on the surface of cancer cells and in the transformed stroma is a common characteristic of aggressive metastatic prostate cancer. We describe here the development of an active site-specific probe for detecting a secreted peritumoral protease expressed by cancer cells and the surrounding tumor microenvironment. Using a human fragment antigen binding phage display library, we identified a human antibody termed U33 that selectively inhibited the active form of the protease urokinase plasminogen activator (uPA, PLAU). In the full-length immunoglobulin form, U33 IgG labeled with near-infrared fluorophores or radionuclides allowed us to non-invasively detect active uPA in prostate cancer xenograft models using optical and single-photon emission computed tomography (SPECT) imaging modalities. U33 IgG labeled with 111In had a remarkable tumor uptake of 43.2% injected dose per gram (%ID/g) 72hr post tail vein injection of the radiolabeled probe in subcutaneous xenografts. Additionally, U33 was able to image active uPA in small soft-tissue and osseous metastatic lesions using a cardiac dissemination prostate cancer model that recapitulated metastatic human cancer. The favorable imaging properties were the direct result of U33 IgG internalization through an uPA receptor mediated mechanism where U33 mimicked the function of the endogenous inhibitor of uPA to gain entry into the cancer cell. Overall, our imaging probe targets a prostate cancer-associated protease, through a unique mechanism, allowing for the non-invasive preclinical imaging of prostate cancer lesions. PMID:25672980

  16. Active gated imaging for automotive safety applications

    NASA Astrophysics Data System (ADS)

    Grauer, Yoav; Sonn, Ezri

    2015-03-01

    The paper presents the Active Gated Imaging System (AGIS), in relation to the automotive field. AGIS is based on a fast gated-camera equipped with a unique Gated-CMOS sensor, and a pulsed Illuminator, synchronized in the time domain to record images of a certain range of interest which are then processed by computer vision real-time algorithms. In recent years we have learned the system parameters which are most beneficial to night-time driving in terms of; field of view, illumination profile, resolution and processing power. AGIS provides also day-time imaging with additional capabilities, which enhances computer vision safety applications. AGIS provides an excellent candidate for camera-based Advanced Driver Assistance Systems (ADAS) and the path for autonomous driving, in the future, based on its outstanding low/high light-level, harsh weather conditions capabilities and 3D potential growth capabilities.

  17. Image Segmentation With Cage Active Contours.

    PubMed

    Garrido, Lluís; Guerrieri, Marité; Igual, Laura

    2015-12-01

    In this paper, we present a framework for image segmentation based on parametrized active contours. The evolving contour is parametrized according to a reduced set of control points that form a closed polygon and have a clear visual interpretation. The parametrization, called mean value coordinates, stems from the techniques used in computer graphics to animate virtual models. Our framework allows to easily formulate region-based energies to segment an image. In particular, we present three different local region-based energy terms: 1) the mean model; 2) the Gaussian model; 3) and the histogram model. We show the behavior of our method on synthetic and real images and compare the performance with state-of-the-art level set methods. PMID:26316128

  18. Multicolor Imaging of Bifacial Activities of Estrogens.

    PubMed

    Kim, Sung-Bae; Umezawa, Yoshio

    2016-01-01

    The present protocol introduces multicolor imaging of bifacial activities of an estrogen. For the multicolor imaging, the authors fabricated two single-chain probes emitting green or red bioluminescence (named Simer-G and -R, respectively) from click beetle luciferase (CBLuc) green and red: Simer-R consists of the ligand binding domain of estrogen receptor (ER LBD) and the Src homology-2 (SH2) domain of Src, which are sandwiched between split-CBLuc red (CBLuc-R). On the other hand, Simer-G emitting red light consists of the ER LBD and a common consensus sequence of coactivators (LXXLL motif), which are inserted between split-CBLuc green (CBLuc-G). This probe set creates fingerprinting spectra from the characteristic green and red bioluminescence in response to agonistic and antagonistic activities of a ligand of interest. The present protocol further provides a unique methodology to calculate characteristic estrogenicity scores of various ligands from the spectra. PMID:27424902

  19. How to be a fig wasp down under: The diversity and structure of an Australian fig wasp community

    NASA Astrophysics Data System (ADS)

    Segar, Simon T.; Dunn, Derek W.; Darwell, Clive T.; Cook, James M.

    2014-05-01

    Endophytic insects and their parasitoids provide valuable models for community ecology. The wasp communities in inflorescences of fig trees have great potential for comparative studies, but we must first describe individual communities. Here, we add to the few detailed studies of such communities by describing the one associated with Ficus rubiginosa in Australia. First, we describe community composition, using two different sampling procedures. Overall, we identified 14 species of non-pollinating fig wasp (NPFW) that fall into two size classes. Small wasps, including pollinators, gallers and their parasitoids, were more abundant than large wasps (both galler and parasitoid species). We show that in figs where wasps emerge naturally, the presence of large wasps may partly explain the low emergence of small wasps. During fig development, large gallers oviposit first, before and around the time of pollination, while parasitoids lay eggs after pollination. We further show that parasitoids in the subfamily Sycoryctinae, which comprise the majority of all individual NPFWs, segregate temporally by laying eggs at different stages of fig development. We discuss our results in terms of species co-existence and community structure and compare our findings to those from fig wasp communities on other continents.

  20. NAIS: Nuclear activation-based imaging spectroscopy

    SciTech Connect

    Günther, M. M.; Britz, A.; Harres, K.; Hoffmeister, G.; Nürnberg, F.; Otten, A.; Pelka, A.; Roth, M.; Clarke, R. J.; Vogt, K.

    2013-07-15

    In recent years, the development of high power laser systems led to focussed intensities of more than 10{sup 22} W/cm{sup 2} at high pulse energies. Furthermore, both, the advanced high power lasers and the development of sophisticated laser particle acceleration mechanisms facilitate the generation of high energetic particle beams at high fluxes. The challenge of imaging detector systems is to acquire the properties of the high flux beam spatially and spectrally resolved. The limitations of most detector systems are saturation effects. These conventional detectors are based on scintillators, semiconductors, or radiation sensitive films. We present a nuclear activation-based imaging spectroscopy method, which is called NAIS, for the characterization of laser accelerated proton beams. The offline detector system is a combination of stacked metal foils and imaging plates (IP). After the irradiation of the stacked foils they become activated by nuclear reactions, emitting gamma decay radiation. In the next step, an autoradiography of the activated foils using IPs and an analysis routine lead to a spectrally and spatially resolved beam profile. In addition, we present an absolute calibration method for IPs.

  1. Imaging Calcium in Drosophila at Egg Activation.

    PubMed

    Derrick, Christopher J; York-Andersen, Anna H; Weil, Timothy T

    2016-01-01

    Egg activation is a universal process that includes a series of events to allow the fertilized egg to complete meiosis and initiate embryonic development. One aspect of egg activation, conserved across all organisms examined, is a change in the intracellular concentration of calcium (Ca(2+)) often termed a 'Ca(2+) wave'. While the speed and number of oscillations of the Ca(2+) wave varies between species, the change in intracellular Ca(2+) is key in bringing about essential events for embryonic development. These changes include resumption of the cell cycle, mRNA regulation, cortical granule exocytosis, and rearrangement of the cytoskeleton. In the mature Drosophila egg, activation occurs in the female oviduct prior to fertilization, initiating a series of Ca(2+)-dependent events. Here we present a protocol for imaging the Ca(2+) wave in Drosophila. This approach provides a manipulable model system to interrogate the mechanism of the Ca(2+) wave and the downstream changes associated with it. PMID:27584955

  2. New Viruses Found in Fig Exhibiting Mosaic Symptoms

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mosaic is the most widespread viral disease of fig, affecting the crop wherever it is grown. The causal agent of the disease was poorly characterized, and until recently it was considered a virus-like agent with double membrane bound semispherical bodies transmitted by eriophyid mites. During the mo...

  3. 21 CFR 145.134 - Canned preserved figs.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... section are whole mature figs of the light or dark varieties that may be either peeled or unpeeled. (c)(1... words “Preserved Figs”, but there shall be no intervening written, printed, or graphic matter, and the... precede or follow such name without intervening written, printed, or graphic matter, except that...

  4. 21 CFR 145.134 - Canned preserved figs.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... section are whole mature figs of the light or dark varieties that may be either peeled or unpeeled. (c)(1... words “Preserved Figs”, but there shall be no intervening written, printed, or graphic matter, and the... precede or follow such name without intervening written, printed, or graphic matter, except that...

  5. 21 CFR 145.134 - Canned preserved figs.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... section are whole mature figs of the light or dark varieties that may be either peeled or unpeeled. (c)(1... words “Preserved Figs”, but there shall be no intervening written, printed, or graphic matter, and the... precede or follow such name without intervening written, printed, or graphic matter, except that...

  6. Aflatoxins in hazelnuts and dried figs: Occurrence and exposure assessment.

    PubMed

    Kabak, Bulent

    2016-11-15

    A total of 300 samples of hazelnuts and dried fig were analysed for the incidence of any aflatoxins (AFs). High-performance liquid chromatography coupled with fluorescence detection (HPLC-FLD) method was used to quantify the amounts of AFs. The limit of quantification varied from 0.21 to 0.30μgkg(-1). No AFs were detected in shells of the hazelnuts, while six raw hazelnut kernel samples (12%) and five roasted hazelnut kernel samples (8.3%) contained AFs ranging from 0.09 to 11.3μgkg(-1) and from 0.17 to 11.2μgkg(-1), respectively. Sixteen dried fig samples (12.3%) contained AFs ranging from 0.1 to 28.2μgkg(-1) and a mean value of 3.8μgkg(-1). Three hazelnuts and six dried fig samples exceeded the European maximum limits (MLs) of 5 and 2μgkg(-1) for aflatoxin B1 (AFB1), respectively. The contribution of hazelnuts to AFs exposure is higher than that of dried figs. PMID:27283601

  7. Interference Competition and High Temperatures Reduce the Virulence of Fig Wasps and Stabilize a Fig-Wasp Mutualism

    PubMed Central

    Sun, Bao-Fa; Zheng, Qi; Dunn, Derek W.; Cook, James; Shi, Lei; Zhang, Ya-Ping; Yu, Douglas W.

    2009-01-01

    Fig trees are pollinated by fig wasps, which also oviposit in female flowers. The wasp larvae gall and eat developing seeds. Although fig trees benefit from allowing wasps to oviposit, because the wasp offspring disperse pollen, figs must prevent wasps from ovipositing in all flowers, or seed production would cease, and the mutualism would go extinct. In Ficus racemosa, we find that syconia (‘figs’) that have few foundresses (ovipositing wasps) are underexploited in the summer (few seeds, few galls, many empty ovules) and are overexploited in the winter (few seeds, many galls, few empty ovules). Conversely, syconia with many foundresses produce intermediate numbers of galls and seeds, regardless of season. We use experiments to explain these patterns, and thus, to explain how this mutualism is maintained. In the hot summer, wasps suffer short lifespans and therefore fail to oviposit in many flowers. In contrast, cooler temperatures in the winter permit longer wasp lifespans, which in turn allows most flowers to be exploited by the wasps. However, even in winter, only in syconia that happen to have few foundresses are most flowers turned into galls. In syconia with higher numbers of foundresses, interference competition reduces foundress lifespans, which reduces the proportion of flowers that are galled. We further show that syconia encourage the entry of multiple foundresses by delaying ostiole closure. Taken together, these factors allow fig trees to reduce galling in the wasp-benign winter and boost galling (and pollination) in the wasp-stressing summer. Interference competition has been shown to reduce virulence in pathogenic bacteria. Our results show that interference also maintains cooperation in a classic, cooperative symbiosis, thus linking theories of virulence and mutualism. More generally, our results reveal how frequency-dependent population regulation can occur in the fig-wasp mutualism, and how a host species can ‘set the rules of the game’ to

  8. Initial assessment of natural diversity in Mexican fig landraces.

    PubMed

    García-Ruiz, M T; Mendoza-Castillo, V M; Valadez-Moctezuma, E; Muratalla-Lúa, A

    2013-01-01

    The common fig (Ficus carica L.) was introduced into Mexico by Spanish Franciscan missionaries in the 16th century. It is widely assumed that Mexican figs are the Spanish cultivar Black Mission. We collected and propagated 12 fig plants from six landraces from different states in Central Mexico that represent different climate. All of them were grown in a greenhouse at Universidad Autónoma Chapingo, in the State of Mexico. During the experimental period, the greenhouse had an average temperature and relative humidity of 29.2° ± 5.4°C (SEM) and 78.1 ± 6.7% (SEM), respectively. Morphological characterization was done following a selected set of quantitative and qualitative descriptors established by the IPGRI. DNA analysis was based on a combination of ISSR and RFLP markers. We observed great diversity mainly in fruit weight (28.1-96.2 g), fruit shape (ovoid, pyriform), and neck length (0.97-3.80 cm), which could not be explained by environmental conditions such as temperature and relative humidity. The Nei and Li/Dice similarity coefficient between landraces was determined by cluster analysis using the UPGMA method. Based on the morphological characterization and DNA fingerprinting data presented in this study, our results showed that after hundreds of years, black figs have adapted to local environmental condition in Central Mexico, yielding at least six clearly distinct landraces that represent valuable and previously undescribed genetic diversity. We also suggested names for those landraces according to their location and established a basis for further agronomic and molecular characterization of fig landraces. PMID:24085455

  9. Electromagnetic imaging of dynamic brain activity

    SciTech Connect

    Mosher, J.; Leahy, R.; Lewis, P.; Lewine, J.; George, J.; Singh, M.

    1991-12-31

    Neural activity in the brain produces weak dynamic electromagnetic fields that can be measured by an array of sensors. Using a spatio-temporal modeling framework, we have developed a new approach to localization of multiple neural sources. This approach is based on the MUSIC algorithm originally developed for estimating the direction of arrival of signals impinging on a sensor array. We present applications of this technique to magnetic field measurements of a phantom and of a human evoked somatosensory response. The results of the somatosensory localization are mapped onto the brain anatomy obtained from magnetic resonance images.

  10. Electromagnetic imaging of dynamic brain activity

    SciTech Connect

    Mosher, J.; Leahy, R. . Dept. of Electrical Engineering); Lewis, P.; Lewine, J.; George, J. ); Singh, M. . Dept. of Radiology)

    1991-01-01

    Neural activity in the brain produces weak dynamic electromagnetic fields that can be measured by an array of sensors. Using a spatio-temporal modeling framework, we have developed a new approach to localization of multiple neural sources. This approach is based on the MUSIC algorithm originally developed for estimating the direction of arrival of signals impinging on a sensor array. We present applications of this technique to magnetic field measurements of a phantom and of a human evoked somatosensory response. The results of the somatosensory localization are mapped onto the brain anatomy obtained from magnetic resonance images.

  11. The adjuvant activity of a non-toxic, water-soluble glycopeptide present in large quantities in the culture filtrate of Mycobacterium tuberculosis strain DT.

    PubMed Central

    Stewart-Tull, D E; Shimono, T; Kotani, S; Kato, M; Ogawa, Y; Yamamura, Y; Koga, T; Pearson, C M

    1975-01-01

    A water-soluble mycobacterial glycopeptide was obtained in large quantities from the culture supernatant fluid of M. tuberculosis strain DT. This glycopeptide was strongly adjuvant-active when injected, in a water-in-oil emulsion contianing ovalbumin, into guinea-pigs. In addition, it was devoid of cord factor toxicity in mice, polyarthritogenic activity in rats and cavity stimulating activity in rabbit lungs. Images FIG. 2 FIG. 3 FIG. 4 FIG. 5 FIG. 6 FIG. 8 PMID:806515

  12. Natural occurrence of ochratoxin A in dried figs.

    PubMed

    Karbancioğlu-Güler, Funda; Heperkan, Dilek

    2008-06-01

    Ochratoxin A (OTA) contamination in dried figs was investigated using high performance liquid chromatography (HPLC) with fluorescence detection after extraction with methanol and orthophosphoric acid and clean up by an immunoaffinity column. The limit of detection for OTA was 0.12 microg kg(-1). One hundred and fifteen samples were taken during the drying stage from 7 different districts in the Aegean Region in 2003 and 2004. Fifty-five (47.2%) of the 115 samples were found to contain detectable levels of ochratoxin A, ranging from 0.12 to 15.31 microg kg(-1). However, the OTA level for a majority of the samples was low, with only 4 samples containing OTA exceeding 1 microg kg(-1). The calculated overall median for the OTA level was below the limit of detection and the overall mean was estimated as 0.52 microg kg(-1). Frequency of ochratoxin A contamination in dried figs harvested in 2003 and 2004 are 47 and 50%, respectively. Highest contamination ratio was determined in dried figs from Erbeyli (60%), followed by Selcuk (56%), and Ortaklar (50%). PMID:18486638

  13. Active index for content-based medical image retrieval.

    PubMed

    Chang, S K

    1996-01-01

    This paper introduces the active index for content-based medical image retrieval. The dynamic nature of the active index is its most important characteristic. With an active index, we can effectively and efficiently handle smart images that respond to accessing, probing and other actions. The main applications of the active index are to prefetch image and multimedia data, and to facilitate similarity retrieval. The experimental active index system is described. PMID:8954230

  14. Culture-free survey reveals diverse and distinctive fungal communities associated with developing figs (Ficus spp.) in Panama.

    PubMed

    Martinson, Ellen O; Herre, Edward Allen; Machado, Carlos A; Arnold, A Elizabeth

    2012-11-01

    The ancient association of figs (Ficus spp.) and their pollinating wasps (fig wasps; Chalcidoidea, Hymenoptera) is one of the most interdependent plant-insect mutualisms known. In addition to pollinating wasps, a diverse community of organisms develops within the microcosm of the fig inflorescence and fruit. To better understand the multipartite context of the fig-fig wasp association, we used a culture-free approach to examine fungal communities associated with syconia of six species of Ficus and their pollinating wasps in lowland Panama. Diverse fungi were recovered from surface-sterilized flowers of all Ficus species, including gall- and seed flowers at four developmental stages. Fungal communities in syconia and on pollinating wasps were similar, dominated by diverse and previously unknown Saccharomycotina, and distinct from leaf- and stem endophyte communities in the same region. Before pollination, fungal communities were similar between gall- and seed flowers and among Ficus species. However, fungal communities differed significantly in flowers after pollination vs. before pollination, and between anciently diverged lineages of Ficus with active vs. passive pollination syndromes. Within groups of relatively closely related figs, there was little evidence for strict-sense host specificity between figs and particular fungal species. Instead, mixing of fungal communities among related figs, coupled with evidence for possible transfer by pollinating wasps, is consistent with recent suggestions of pollinator mixing within syconia. In turn, changes in fungal communities during fig development and ripening suggest an unexplored role of yeasts in the context of the fig-pollinator wasp mutualism. PMID:22729017

  15. Synergistic Effects of Crizotinib and Temozolomide in Experimental FIG-ROS1 Fusion-Positive Glioblastoma

    PubMed Central

    Das, Arabinda; Cheng, Ron Ron; Hilbert, Megan L.T.; Dixon-Moh, Yaenette N.; Decandio, Michele; Vandergrift, William Alex; Banik, Naren L.; Lindhorst, Scott M.; Cachia, David; Varma, Abhay K.; Patel, Sunil J.; Giglio, Pierre

    2015-01-01

    Glioblastoma (GB) is the most common malignant brain tumor. Drug resistance frequently develops in these tumors during chemotherapy. Therefore, predicting drug response in these patients remains a major challenge in the clinic. Thus, to improve the clinical outcome, more effective and tolerable combination treatment strategies are needed. Robust experimental evidence has shown that the main reason for failure of treatments is signal redundancy due to coactivation of several functionally linked receptor tyrosine kinases (RTKs), including anaplastic lymphoma kinase (ALK), c-Met (hepatocyte growth factor receptor), and oncogenic c-ros oncogene1 (ROS1: RTK class orphan) fusion kinase FIG (fused in GB)-ROS1. As such, these could be attractive targets for GB therapy. The study subjects consisted of 19 patients who underwent neurosurgical resection of GB tissues. Our in vitro and ex vivo models promisingly demonstrated that treatments with crizotinib (PF-02341066: dual ALK/c-Met inhibitor) and temozolomide in combination induced synergistic antitumor activity on FIG-ROS1-positive GB cells. Our results also showed that ex vivo FIG-ROS1+ slices (obtained from GB patients) when cultured were able to preserve tissue architecture, cell viability, and global gene-expression profiles for up to 14 days. Both in vitro and ex vivo studies indicated that combination blockade of FIG, p-ROS1, p-ALK, and p-Met augmented apoptosis, which mechanistically involves activation of Bim and inhibition of survivin, p-Akt, and Mcl-1 expression. However, it is important to note that we did not see any significant synergistic effect of crizotinib and temozolomide on FIG-ROS1-negative GB cells. Thus, these ex vivo culture results will have a significant impact on patient selection for clinical trials and in predicting response to crizotinib and temozolomide therapy. Further studies in different animal models of FIG-ROS1-positive GB cells are warranted to determine useful therapies for the

  16. International standards activities in image data compression

    NASA Technical Reports Server (NTRS)

    Haskell, Barry

    1989-01-01

    Integrated Services Digital Network (ISDN); coding for color TV, video conferencing, video conferencing/telephone, and still color images; ISO color image coding standard; and ISO still picture standard are briefly discussed. This presentation is represented by viewgraphs only.

  17. Natural image classification driven by human brain activity

    NASA Astrophysics Data System (ADS)

    Zhang, Dai; Peng, Hanyang; Wang, Jinqiao; Tang, Ming; Xue, Rong; Zuo, Zhentao

    2016-03-01

    Natural image classification has been a hot topic in computer vision and pattern recognition research field. Since the performance of an image classification system can be improved by feature selection, many image feature selection methods have been developed. However, the existing supervised feature selection methods are typically driven by the class label information that are identical for different samples from the same class, ignoring with-in class image variability and therefore degrading the feature selection performance. In this study, we propose a novel feature selection method, driven by human brain activity signals collected using fMRI technique when human subjects were viewing natural images of different categories. The fMRI signals associated with subjects viewing different images encode the human perception of natural images, and therefore may capture image variability within- and cross- categories. We then select image features with the guidance of fMRI signals from brain regions with active response to image viewing. Particularly, bag of words features based on GIST descriptor are extracted from natural images for classification, and a sparse regression base feature selection method is adapted to select image features that can best predict fMRI signals. Finally, a classification model is built on the select image features to classify images without fMRI signals. The validation experiments for classifying images from 4 categories of two subjects have demonstrated that our method could achieve much better classification performance than the classifiers built on image feature selected by traditional feature selection methods.

  18. Papain Induced Occupational Asthma with Kiwi and Fig Allergy

    PubMed Central

    Jiang, Nannan; Yin, Jia

    2016-01-01

    Papain is a proteolytic enzyme which is widely used in food industry, pharmaceuticals, and cosmetics. Occupational and non-occupational papain allergies have previously been documented; however, there are limited publications about papain allergy with its relative fruit allergy. Here, we present a case of occupational, IgE-mediated papain allergy with kiwi fruit and fig fruit allergy. A 53-year-old man suffered from rhinitis for several years, with the onset of his symptoms coinciding with the time he started to work at a sausage processing plant where papain is often used as a meat tenderizer. He began to experience symptoms of chest tightness, shortness of breath and wheezing shortly after starting work 5 years ago. Furthermore, he experienced several episodes of oral itching, and tongue and oropharyngeal angioedema after injestion of kiwi fruit and fig fruit. The patient had a lifelong history of allergic conjunctivitis, allergic rhinitis, and childhood asthma. Specific IgE was positive to kiwi fruit, papain and chymopapain (2.95 kUA/L, >100 kUA/L, and 95.0 kUA/L, respectively). Similar bands at 10-15 kDa in blotting with papain and kiwi fruit extracts were found. This patient showed a potential association between papain allergy and sensitization to kiwi fruit. We also reviewed 13 patients with papain allergy published in the literature, with 85% (11/13) of the patients sensitized through the respiratory tract, and 40% (4/11) having atopy. Further studies should focus on the determination of cross-reactive allergens between papain and its fruit relatives, and the prevalence of food allergy in patients with papain allergy should be investigated in a relatively large cohort. PMID:26739411

  19. Papain Induced Occupational Asthma with Kiwi and Fig Allergy.

    PubMed

    Jiang, Nannan; Yin, Jia; Wen, Liping

    2016-03-01

    Papain is a proteolytic enzyme which is widely used in food industry, pharmaceuticals, and cosmetics. Occupational and non-occupational papain allergies have previously been documented; however, there are limited publications about papain allergy with its relative fruit allergy. Here, we present a case of occupational, IgE-mediated papain allergy with kiwi fruit and fig fruit allergy. A 53-year-old man suffered from rhinitis for several years, with the onset of his symptoms coinciding with the time he started to work at a sausage processing plant where papain is often used as a meat tenderizer. He began to experience symptoms of chest tightness, shortness of breath and wheezing shortly after starting work 5 years ago. Furthermore, he experienced several episodes of oral itching, and tongue and oropharyngeal angioedema after injestion of kiwi fruit and fig fruit. The patient had a lifelong history of allergic conjunctivitis, allergic rhinitis, and childhood asthma. Specific IgE was positive to kiwi fruit, papain and chymopapain (2.95 kUA/L, >100 kUA/L, and 95.0 kUA/L, respectively). Similar bands at 10-15 kDa in blotting with papain and kiwi fruit extracts were found. This patient showed a potential association between papain allergy and sensitization to kiwi fruit. We also reviewed 13 patients with papain allergy published in the literature, with 85% (11/13) of the patients sensitized through the respiratory tract, and 40% (4/11) having atopy. Further studies should focus on the determination of cross-reactive allergens between papain and its fruit relatives, and the prevalence of food allergy in patients with papain allergy should be investigated in a relatively large cohort. PMID:26739411

  20. Image change detection using a SWIR active imaging system

    NASA Astrophysics Data System (ADS)

    Schneider, Armin L.; Monnin, David; Laurenzis, Martin; Christnacher, Frank

    2013-10-01

    We are currently developing a system consisting of a GPS receiver, a three-axis magnetic compass as well as a digital video camera in order to visualize changes occuring along a regularily used itinerary. This is done by comparing actual images with images from the same scene, which have been acquired during a previous measurement. The luminosity of images from two different passages however can be quite different (due to different meteorological conditions). Whereas the global luminosity can be adjusted using non-linear luminosity correction, the treatment of shadows is more di cult. Since meteorological conditions cannot be controlled, we are investigating the possibility of using a Laser Gated Viewing system in the SWIR domain to illuminate the scene. Using appropriate filters for the camera, we are completely independent of natural illumination and in addition, the system can also be used at night.

  1. Echocardiographic image of an active human heart

    NASA Technical Reports Server (NTRS)

    2003-01-01

    Echocardiographic images provide quick, safe images of the heart as it beats. While a state-of-the art echocardiograph unit is part of the Human Research Facility on International Space Station, quick transmission of images and data to Earth is a challenge. NASA is developing techniques to improve the echocardiography available to diagnose sick astronauts as well as study the long-term effects of space travel on their health. Echocardiography uses ultrasound, generated in a sensor head placed against the patient's chest, to produce images of the structure of the heart walls and valves. However, ultrasonic imaging creates an enormous volume of data, up to 220 million bits per second. This can challenge ISS communications as well as Earth-based providers. Compressing data for rapid transmission back to Earth can degrade the quality of the images. Researchers at the Cleveland Clinic Foundation are working with NASA to develop compression techniques that meet imaging standards now used on the Internet and by the medical community, and that ensure that physicians receive quality diagnostic images.

  2. The effect of fig wall thickness in Ficus erecta var. beecheyana on parasitism

    NASA Astrophysics Data System (ADS)

    Tzeng, Hsy-Yu; Ou, Chern-Hsiung; Lu, Fu-Yuan; Bain, Anthony; Chou, Lien-Siang; Kjellberg, Finn

    2014-05-01

    Fig wasp communities constitute a model system to analyse determinants of community complexity and to investigate how biological interaction networks are maintained. It has been suggested for monoecious figs, that fig pollinating wasps avoid ovipositing in flowers located close to the fig wall because of strong parasitic pressure by wasps ovipositing through the fig wall. This behaviour could help explain why mainly seeds are produced in flowers located close to the fig wall, thus stabilizing the fig-pollinating wasp mutualism. In this contribution we explore, for dioecious figs, whether ovipositor length of parasitic species may really be limiting. In dioecious figs, functionally male figs produce pollinating wasps and pollen while female figs produce only seeds, facilitating selection of traits favouring pollinator reproduction in male figs. We show in Ficus erecta that fig walls are thicker in male figs than in female figs. Male figs presenting thick walls, thicker than the length of the parasites' ovipositors, went unparasitized while male figs presenting thinner walls were systematically parasitized. Hence, in F. erecta, ovipositor length of the parasites is limiting access to some figs. However, we also show that in another dioecious species, Ficus formosana, presenting thin walled male figs, no fig is protected against oviposition by its two parasites. Hence in dioecious as well as in monoecious figs, in some Ficus species, ovipositors of the parasites are limiting access to ovules, while in other Ficus species all ovules are exposed to parasitism.

  3. Active and passive millimeter- and sub-millimeter-wave imaging

    NASA Astrophysics Data System (ADS)

    Petkie, Douglas T.; De Lucia, Frank C.; Castro, Corey; Helminger, Paul; Jacobs, Eddie L.; Moyer, Steven K.; Murrill, Steve; Halford, Carl; Griffin, Steve; Franck, Charmaine

    2005-11-01

    We have developed several millimeter/submillimeter/terahertz systems to study active and passive imaging and associated phenomenology. For measuring the transmission and scattering properties of materials, we have developed a dual rotary stage scattering system with active illumination and a Fourier Transform spectrometer. For imaging studies, we have developed a system based on a 12-inch diameter raster-scanned mirror. By interchange of active sources and both heterodyne and bolometric detectors, this system can be used in a variety of active and passive configurations. The laboratory measurements are used as inputs for, and model calibration and validation of, a terahertz imaging system performance model used to evaluate different imaging modalities for concealed weapon identification. In this paper, we will present examples of transmission and scattering measurements for common clothing as well as active imaging results that used a 640 GHz source and receiver.

  4. Chronic Dietary Supplementation of 4% Figs on the Modification of Oxidative Stress in Alzheimer's Disease Transgenic Mouse Model

    PubMed Central

    Essa, Musthafa Mohamed; Al-Asmi, Abdullah; Vaishnav, Ragini

    2014-01-01

    We assessed the changes in the plasma Aβ, oxidative stress/antioxidants, and membrane bound enzymes in the cerebral cortex and hippocampus of Alzheimer's disease (AD) transgenic mice (Tg2576) after dietary supplementation of Omani figs fruits for 15 months along with spatial memory and learning test. AD Tg mice on control diet without figs showed significant impairment in spatial learning ability compared to the wild-type mice on same diet and figs fed Tg mice as well. Significant increase in oxidative stress and reduced antioxidant status were observed in AD Tg mice. 4% figs treated AD Tg mice significantly attenuated oxidative damage, as evident by decreased lipid peroxidation and protein carbonyls and restoration of antioxidant status. Altered activities of membrane bound enzymes (Na+ K+ ATPase and acetylcholinesterase (AChE)) in AD Tg mice brain regions and was restored by figs treatment. Further, figs supplementation might be able to decrease the plasma levels of Aβ (1–40, 1–42) significantly in Tg mice suggesting a putative delay in the formation of plaques, which might be due to the presence of high natural antioxidants in figs. But this study warrants further extensive investigation to find a novel lead for a therapeutic target for AD from figs. PMID:25050360

  5. Hemodynamic responses to functional activation accessed by optical imaging

    NASA Astrophysics Data System (ADS)

    Ni, Songlin; Li, Pengcheng; Yang, Yuanyuan; Lv, Xiaohua; Luo, Qingming

    2006-01-01

    A multi-wavelength light-emitting diode (LED) and laser diode (LD) based optical imaging system was developed to visualize the changes in cerebral blood flow, oxygenation following functional activation simultaneously in rodent cortex. The 2-D blood flow image was accessed by laser speckle contrast imaging, and the spectroscopic imaging of intrinsic signal was used for the calculation of oxyhemoglobin (HbO), deoxyhemoglobin (Hb) and total hemoglobin (HbT) concentration. The combination of spectroscopic imaging and laser speckle contrast imaging provides the capability to simultaneously investigate the spatial and temporal blood flow and hemoglobin concentration changes with high resolution, which may lead to a better understanding of the coupling between neuronal activation and vascular responses. The optical imaging system been built is compact and convenient to investigators. And it is reliable to acquire raw data. In present study, the hemodynamic responses to cortical spreading depression (CSD) in parietal cortex of ~-chloralose/urethan anesthetized rats were demonstrated.

  6. X-ray imaging with amorphous silicon active matrix flat-panel imagers (AMFPIs)

    NASA Astrophysics Data System (ADS)

    El-Mohri, Youcef; Antonuk, Larry E.; Jee, Kyung-Wook; Maolinbay, Manat; Rong, Xiujiang; Siewerdsen, Jeffrey H.; Verma, Manav; Zhao, Qihua

    1997-07-01

    Recent advances in thin-film electronics technology have opened the way for the use of flat-panel imagers in a number of medical imaging applications. These novel imagers offer real time digital readout capabilities (˜30 frames per second), radiation hardness (>106cGy), large area (30×40 cm2) and compactness (˜1 cm). Such qualities make them strong candidates for the replacement of conventional x-ray imaging technologies such as film-screen and image intensifier systems. In this report, qualities and potential of amorphous silicon based active matrix flat-panel imagers are outlined for various applications such as radiation therapy, radiography, fluoroscopy and mammography.

  7. Flyception: imaging brain activity in freely walking fruit flies.

    PubMed

    Grover, Dhruv; Katsuki, Takeo; Greenspan, Ralph J

    2016-07-01

    Genetically encoded calcium sensors have enabled monitoring of neural activity in vivo using optical imaging techniques. Linking neural activity to complex behavior remains challenging, however, as most imaging systems require tethering the animal, which can impact the animal's behavioral repertoire. Here, we report a method for monitoring the brain activity of untethered, freely walking Drosophila melanogaster during sensorially and socially evoked behaviors to facilitate the study of neural mechanisms that underlie naturalistic behaviors. PMID:27183441

  8. Deep trap, laser activated image converting system

    NASA Technical Reports Server (NTRS)

    Maserjian, J. (Inventor)

    1975-01-01

    Receiving an optical image on the surface of a photoconducting semiconductor is presented, storing the image in deep traps of the semiconductor, and later scanning the semiconductor with a laser beam to empty the deep traps, thereby producing a video signal. The semiconductor is illuminated with photons of energy greater than the band gap producing electron-hole pairs in the semiconductor which subsequently fill traps in energy from the band edges. When the laser beam of low energy photons excites the trapped electrons and holes out of the traps into the conduction and valence bands, a photoconductivity can be observed.

  9. Being active after a heart attack (image)

    MedlinePlus

    ... best activity when you start exercising after a heart attack. Start slowly, and increase the amount of time ... best activity when you start exercising after a heart attack. Start slowly, and increase the amount of time ...

  10. ACTIM: an EDA initiated study on spectral active imaging

    NASA Astrophysics Data System (ADS)

    Steinvall, O.; Renhorn, I.; Ahlberg, J.; Larsson, H.; Letalick, D.; Repasi, E.; Lutzmann, P.; Anstett, G.; Hamoir, D.; Hespel, L.; Boucher, Y.

    2010-10-01

    This paper will describe ongoing work from an EDA initiated study on Active Imaging with emphasis of using multi or broadband spectral lasers and receivers. Present laser based imaging and mapping systems are mostly based on a fixed frequency lasers. On the other hand great progress has recently occurred in passive multi- and hyperspectral imaging with applications ranging from environmental monitoring and geology to mapping, military surveillance, and reconnaissance. Data bases on spectral signatures allow the possibility to discriminate between different materials in the scene. Present multi- and hyperspectral sensors mainly operate in the visible and short wavelength region (0.4-2.5 μm) and rely on the solar radiation giving shortcoming due to shadows, clouds, illumination angles and lack of night operation. Active spectral imaging however will largely overcome these difficulties by a complete control of the illumination. Active illumination enables spectral night and low-light operation beside a robust way of obtaining polarization and high resolution 2D/3D information. Recent development of broadband lasers and advanced imaging 3D focal plane arrays has led to new opportunities for advanced spectral and polarization imaging with high range resolution. Fusing the knowledge of ladar and passive spectral imaging will result in new capabilities in the field of EO-sensing to be shown in the study. We will present an overview of technology, systems and applications for active spectral imaging and propose future activities in connection with some prioritized applications.

  11. Circularly polarized antennas for active holographic imaging through barriers

    SciTech Connect

    McMakin, Douglas L; Severtsen, Ronald H; Lechelt, Wayne M; Prince, James M

    2011-07-26

    Circularly-polarized antennas and their methods of use for active holographic imaging through barriers. The antennas are dielectrically loaded to optimally match the dielectric constant of the barrier through which images are to be produced. The dielectric loading helps to remove barrier-front surface reflections and to couple electromagnetic energy into the barrier.

  12. A 128 x 128 CMOS Active Pixel Image Sensor for Highly Integrated Imaging Systems

    NASA Technical Reports Server (NTRS)

    Mendis, Sunetra K.; Kemeny, Sabrina E.; Fossum, Eric R.

    1993-01-01

    A new CMOS-based image sensor that is intrinsically compatible with on-chip CMOS circuitry is reported. The new CMOS active pixel image sensor achieves low noise, high sensitivity, X-Y addressability, and has simple timing requirements. The image sensor was fabricated using a 2 micrometer p-well CMOS process, and consists of a 128 x 128 array of 40 micrometer x 40 micrometer pixels. The CMOS image sensor technology enables highly integrated smart image sensors, and makes the design, incorporation and fabrication of such sensors widely accessible to the integrated circuit community.

  13. Active Metamaterials for Terahertz Communication and Imaging

    NASA Astrophysics Data System (ADS)

    Rout, Saroj

    In recent years there has been significant interest in terahertz (THz) systems mostly due to their unique applications in communication and imaging. One of the primary reason for this resurgence is the use of metamaterials to design THz devices due to lack of natural materials that can respond to this electromagnetic spectrum, the so-called ''THz gap''. Even after years of intense research, THz systems are complex and expensive, unsuitable for mainstream applications. This work focuses on bridging this gap by building all solid-state THz devices for imaging and communication applications in a commercial integrated circuit (IC) technology. One such canonical device is a THz wave modulator that can be used in THz wireless communication devices and as spatial light modulator (SLM) for THz imaging systems. The key contribution of this thesis is a metamaterial based THz wave modulator fabricated in a commercial gallium arsenide (GaAs) process resonant at 0.46 THz using a novel approach of embedding pseudomorphic high electron mobility transistors (pHEMTs) in metamaterial and demonstrate modulation values over 30%, and THz modulation at frequencies up to 10 MHz. Using the THz wave modulator, we fabricated and experimentally demonstrated an all solid-state metamaterial based THz spatial light modulator (SLM) as a 2x2 pixel array operating around 0.46 THz, by raster scanning an occluded metal object in polystyrene using a single-pixel imaging setup. This was an important step towards building an low-voltage (1V), low power, on-chip integrable THz imaging device. Using the characterization result from the THz SLM, we computationally demonstrated a multi-level amplitude shift keying (ASK) terahertz wireless communication system using spatial light modulation instead of traditional voltage mode modulation, achieving higher spectral efficiency for high speed communication. We show two orders of magnitude improvement in symbol error rate (SER) for a degradation of 20 dB in

  14. Using Digital Imaging in Classroom and Outdoor Activities.

    ERIC Educational Resources Information Center

    Thomasson, Joseph R.

    2002-01-01

    Explains how to use digital cameras and related basic equipment during indoor and outdoor activities. Uses digital imaging in general botany class to identify unknown fungus samples. Explains how to select a digital camera and other necessary equipment. (YDS)

  15. Molecular Imaging of the ATM Kinase Activity

    SciTech Connect

    Williams, Terence M.; Nyati, Shyam; Ross, Brian D.; Rehemtulla, Alnawaz

    2013-08-01

    Purpose: Ataxia telangiectasia mutated (ATM) is a serine/threonine kinase critical to the cellular DNA-damage response, including from DNA double-strand breaks. ATM activation results in the initiation of a complex cascade of events including DNA damage repair, cell cycle checkpoint control, and survival. We sought to create a bioluminescent reporter that dynamically and noninvasively measures ATM kinase activity in living cells and subjects. Methods and Materials: Using the split luciferase technology, we constructed a hybrid cDNA, ATM-reporter (ATMR), coding for a protein that quantitatively reports on changes in ATM kinase activity through changes in bioluminescence. Results: Treatment of ATMR-expressing cells with ATM inhibitors resulted in a dose-dependent increase in bioluminescence activity. In contrast, induction of ATM kinase activity upon irradiation resulted in a decrease in reporter activity that correlated with ATM and Chk2 activation by immunoblotting in a time-dependent fashion. Nuclear targeting improved ATMR sensitivity to both ATM inhibitors and radiation, whereas a mutant ATMR (lacking the target phosphorylation site) displayed a muted response. Treatment with ATM inhibitors and small interfering (si)RNA-targeted knockdown of ATM confirm the specificity of the reporter. Using reporter expressing xenografted tumors demonstrated the ability of ATMR to report in ATM activity in mouse models that correlated in a time-dependent fashion with changes in Chk2 activity. Conclusions: We describe the development and validation of a novel, specific, noninvasive bioluminescent reporter that enables monitoring of ATM activity in real time, in vitro and in vivo. Potential applications of this reporter include the identification and development of novel ATM inhibitors or ATM-interacting partners through high-throughput screens and in vivo pharmacokinetic/pharmacodynamic studies of ATM inhibitors in preclinical models.

  16. Characterization of fig achenes' oil of Ficus carica grown in Tunisia.

    PubMed

    Soltana, Hala; Tekaya, Meriem; Amri, Zahra; El-Gharbi, Sinda; Nakbi, Amel; Harzallah, Arij; Mechri, Beligh; Hammami, Mohamed

    2016-04-01

    This work investigated the composition of the oil extract from achenes of "Kholi" variety of Ficus carica, grown in Tunisia. Fatty acid and sterol compositions were analyzed by gas chromatography (GC) coupled to flame ionization detector (FID). Furthermore, the antioxidant capacity in fig achenes' oil was assessed by employing two different in vitro assays such as DPPH, ABTS(+) radical scavenging capacities. Our results indicated that the fig achenes' oil is a rich source of bioactive molecules. The soxhlet n-hexane extraction of these achenes produced a total oil yield of 16.24%. The predominant fatty acid was linolenic acid. Concerning phytosterols, the total amount reached 1061.45 mg/100 g with a predominance of Δ(5,23)-stigmastadienol (73.78%). Regarding antioxidant activities, the half maximal inhibitory concentration (IC50) was 215.86 μg/ml and Trolox equivalent antioxidant capacity (TEAC) was 95.25 mM. These data indicate that fig achenes oil of F. carica could be potentially useful in food and pharmaceutical applications. PMID:26593597

  17. Active-Pixel Image Sensors With Programmable Resolution

    NASA Technical Reports Server (NTRS)

    Kemeny, Sabrina E.; Fossum, Eric R.; Pain, Bedabrata; Nakamura, Junichi; Matthies, Larry H.

    1996-01-01

    Active-pixel image sensors with programmable resolution proposed for use in applications in which speed and efficiency of processing of image data enhanced by providing those data at varying resolutions. Such applications include modeling of biological vision, stereoscopic range-finding, recognition of patterns, tracking targets, and progressive transmission of compressed images. In target-tracking application, sensor initially forms low-resolution image from which area of interest identified, then sensor set at high resolution for examination of identified area. Outputs of contiguous pixels combined. Sensor of this type made to act as though it comprised fewer and larger pixels.

  18. Spatial Segmentation of Image Sequences Based on Their Time Activity

    NASA Astrophysics Data System (ADS)

    Galatsanos, N. P.

    2006-04-01

    There are many applications in medical imaging where one is interested in finding the areas of the image that exhibit the same time activity. Such applications occur in positron and single photon emission imaging as well as in perfusion studies with magnetic resonance imaging (MRI). In this talk we will present Bayesian methodology based on clustering to solve this problem. At first the dimensionality of the pixel observations is reduced using a probabilistic principle component model along the spatial dimension of the data. Then, a multidimensional Gaussian mixture model with spatial constraints is used for clustering. Examples from MRI perfusion studies of the heart and the brain will be shown.

  19. Physiological basis and image processing in functional magnetic resonance imaging: Neuronal and motor activity in brain

    PubMed Central

    Sharma, Rakesh; Sharma, Avdhesh

    2004-01-01

    Functional magnetic resonance imaging (fMRI) is recently developing as imaging modality used for mapping hemodynamics of neuronal and motor event related tissue blood oxygen level dependence (BOLD) in terms of brain activation. Image processing is performed by segmentation and registration methods. Segmentation algorithms provide brain surface-based analysis, automated anatomical labeling of cortical fields in magnetic resonance data sets based on oxygen metabolic state. Registration algorithms provide geometric features using two or more imaging modalities to assure clinically useful neuronal and motor information of brain activation. This review article summarizes the physiological basis of fMRI signal, its origin, contrast enhancement, physical factors, anatomical labeling by segmentation, registration approaches with examples of visual and motor activity in brain. Latest developments are reviewed for clinical applications of fMRI along with other different neurophysiological and imaging modalities. PMID:15125779

  20. Imaging techniques for assaying lymphocyte activation in action

    PubMed Central

    Balagopalan, Lakshmi; Sherman, Eilon; Barr, Valarie A.; Samelson, Lawrence E.

    2012-01-01

    Imaging techniques have greatly improved our understanding of lymphocyte activation. Technical advances in spatial and temporal resolution and new labelling tools have enabled researchers to directly observe the activation process. Consequently, research using imaging approaches to study lymphocyte activation has expanded, providing an unprecedented level of cellular and molecular detail in the field. As a result, certain models of lymphocyte activation have been verified, others have been revised and yet others have been replaced with new concepts. In this article, we review the current imaging techniques that are used to assess lymphocyte activation in different contexts, from whole animals to single molecules, and discuss the advantages and potential limitations of these methods. PMID:21179118

  1. Expression and evolutionary divergence of the non-conventional olfactory receptor in four species of fig wasp associated with one species of fig

    PubMed Central

    Lu, Bin; Wang, Nina; Xiao, Jinhua; Xu, Yongyu; Murphy, Robert W; Huang, Dawei

    2009-01-01

    Background The interactions of fig wasps and their host figs provide a model for investigating co-evolution. Fig wasps have specialized morphological characters and lifestyles thought to be adaptations to living in the fig's syconium. Although these aspects of natural history are well documented, the genetic mechanism(s) underlying these changes remain(s) unknown. Fig wasp olfaction is the key to host-specificity. The Or83b gene class, an unusual member of olfactory receptor family, plays a critical role in enabling the function of conventional olfactory receptors. Four Or83b orthologous genes from one pollinator (PFW) (Ceratosolen solmsi) and three non-pollinator fig wasps (NPFWs) (Apocrypta bakeri, Philotrypesis pilosa and Philotrypesis sp.) associated with one species of fig (Ficus hispida) can be used to better understand the molecular mechanism underlying the fig wasp's adaptation to its host. We made a comparison of spatial tissue-specific expression patterns and substitution rates of one orthologous gene in these fig wasps and sought evidence for selection pressures. Results A newly identified Or83b orthologous gene was named Or2. Expressions of Or2 were restricted to the heads of all wingless male fig wasps, which usually live in the dark cavity of a fig throughout their life cycle. However, expressions were widely detected in the antennae, legs and abdomens of all female fig wasps that fly from one fig to another for oviposition, and secondarily pollination. Weak expression was also observed in the thorax of PFWs. Compared with NPFWs, the Or2 gene in C. solmsi had an elevated rate of substitutions and lower codon usage. Analyses using Tajima's D, Fu and Li's D* and F* tests indicated a non-neutral pattern of nucleotide variation in all fig wasps. Unlike in NPFWs, this non-neutral pattern was also observed for synonymous sites of Or2 within PFWs. Conclusion The sex- and species-specific expression patterns of Or2 genes detected beyond the known primary

  2. When should fig fruit produce volatiles? Pattern in a ripening process

    NASA Astrophysics Data System (ADS)

    Borges, Renee M.; Ranganathan, Yuvaraj; Krishnan, Anusha; Ghara, Mahua; Pramanik, Gautam

    2011-11-01

    Ripe fruit need to signal their presence to attract dispersal agents. Plants may employ visual and/or olfactory sensory channels to signal the presence of ripe fruit. Visual signals of ripe fruit have been extensively investigated. However, the volatile signatures of ripe fruit that use olfactorily-oriented dispersers have been scarcely investigated. Moreover, as in flowers, where floral scents are produced at times when pollinators are active (diurnal versus nocturnal), whether plants can modulate the olfactory signal to produce fruit odours when dispersers are active in the diel cycle is completely unknown. We investigated day-night differences in fruit odours in two species of figs, Ficus racemosa and Ficus benghalensis. The volatile bouquet of fruit of F. racemosa that are largely dispersed by bats and other mammals was dominated by fatty acid derivatives such as esters. In this species in which the ripe fig phase is very short, and where the figs drop off soon after ripening, there were no differences between day and night in fruit volatile signature. The volatile bouquet of fruit of F. benghalensis that has a long ripening period, however, and that remain attached to the tree for extended periods when ripe, showed an increase in fatty acid derivatives such as esters and of benzenoids such as benzaldehyde at night when they are dispersed by bats, and an elevation of sesquiterpenes during the day when they are dispersed by birds. For the first time we provide data that suggest that the volatile signal produced by fruit can show diel differences based on the activity period of the dispersal agent.

  3. An Investigation of Implicit Active Contours for Scientific Image Segmentation

    SciTech Connect

    Weeratunga, S K; Kamath, C

    2003-10-29

    The use of partial differential equations in image processing has become an active area of research in the last few years. In particular, active contours are being used for image segmentation, either explicitly as snakes, or implicitly through the level set approach. In this paper, we consider the use of the implicit active contour approach for segmenting scientific images of pollen grains obtained using a scanning electron microscope. Our goal is to better understand the pros and cons of these techniques and to compare them with the traditional approaches such as the Canny and SUSAN edge detectors. The preliminary results of our study show that the level set method is computationally expensive and requires the setting of several different parameters. However, it results in closed contours, which may be useful in separating objects from the background in an image.

  4. Purification and autolysis of the ficin isoforms from fig (Ficus carica cv. Sabz) latex

    PubMed Central

    Zare, Hamid; Moosavi-Movahedi, Ali Akbar; Salami, Maryam; Mirzaei, Morteza; Saboury, Ali Akbar; Sheibani, Nader

    2013-01-01

    Ficin (EC 3.4.22.3), a cysteine endoproteolytic protease in fig trees’ latex, has multiple isoforms. Until now, no data on autolysis of individual ficins (ficin isoforms) are available. Following purification, ficins’ autolysis was determined by HPLC chromatogram changes and ultrafiltrations at different temperatures and storage times. These results showed that the number of HPLC peaks in latex proteins purification of Ficus carica cv. Sabz varied from previous fig varieties or cultivars. Proteolytic activity of ficins was inhibited by specific cysteine protease inhibitors, confirming the participation of the cysteine residue in the active site. The zeta potential of the first two eluted peaks (I and II) was negative, while that of other peaks were positive. All ficins were susceptible to autolysis when stored at high temperatures. In contrast, only the last two ficins (B, C) were prone to autolysis at cold temperature after long storage period. The rate of degradation of the ficins was significantly increased with the increased storage time. The ficin (A) related to peak (III) had the highest and the lowest surface hydrophobic patches and ratio of autolytic to proteolytic activity, respectively. PMID:23312458

  5. CMOS Active-Pixel Image Sensor With Simple Floating Gates

    NASA Technical Reports Server (NTRS)

    Fossum, Eric R.; Nakamura, Junichi; Kemeny, Sabrina E.

    1996-01-01

    Experimental complementary metal-oxide/semiconductor (CMOS) active-pixel image sensor integrated circuit features simple floating-gate structure, with metal-oxide/semiconductor field-effect transistor (MOSFET) as active circuit element in each pixel. Provides flexibility of readout modes, no kTC noise, and relatively simple structure suitable for high-density arrays. Features desirable for "smart sensor" applications.

  6. Infrared active polarimetric imaging system controlled by image segmentation algorithms: application to decamouflage

    NASA Astrophysics Data System (ADS)

    Vannier, Nicolas; Goudail, François; Plassart, Corentin; Boffety, Matthieu; Feneyrou, Patrick; Leviandier, Luc; Galland, Frédéric; Bertaux, Nicolas

    2016-05-01

    We describe an active polarimetric imager with laser illumination at 1.5 µm that can generate any illumination and analysis polarization state on the Poincar sphere. Thanks to its full polarization agility and to image analysis of the scene with an ultrafast active-contour based segmentation algorithm, it can perform adaptive polarimetric contrast optimization. We demonstrate the capacity of this imager to detect manufactured objects in different types of environments for such applications as decamouflage and hazardous object detection. We compare two imaging modes having different number of polarimetric degrees of freedom and underline the characteristics that a polarimetric imager aimed at this type of applications should possess.

  7. Active and interactive floating image display using holographic 3D images

    NASA Astrophysics Data System (ADS)

    Morii, Tsutomu; Sakamoto, Kunio

    2006-08-01

    We developed a prototype tabletop holographic display system. This system consists of the object recognition system and the spatial imaging system. In this paper, we describe the recognition system using an RFID tag and the 3D display system using a holographic technology. A 3D display system is useful technology for virtual reality, mixed reality and augmented reality. We have researched spatial imaging and interaction system. We have ever proposed 3D displays using the slit as a parallax barrier, the lenticular screen and the holographic optical elements(HOEs) for displaying active image 1,2,3. The purpose of this paper is to propose the interactive system using these 3D imaging technologies. In this paper, the authors describe the interactive tabletop 3D display system. The observer can view virtual images when the user puts the special object on the display table. The key technologies of this system are the object recognition system and the spatial imaging display.

  8. Traditional agroecosystems as conservatories and incubators of cultivated plant varietal diversity: the case of fig (Ficus carica L.) in Morocco

    PubMed Central

    2010-01-01

    Background Traditional agroecosystems are known to host both large crop species diversity and high within crop genetic diversity. In a context of global change, this diversity may be needed to feed the world. Are these agroecosystems museums (i.e. large core collections) or cradles of diversity? We investigated this question for a clonally propagated plant, fig (Ficus carica), within its native range, in Morocco, but as far away as possible from supposed centers of domestication. Results Fig varieties were locally numerous. They were found to be mainly highly local and corresponded to clones propagated vegetatively. Nevertheless these clones were often sufficiently old to have accumulated somatic mutations for selected traits (fig skin color) and at neutral loci (microsatellite markers). Further the pattern of spatial genetic structure was similar to the pattern expected in natural population for a mutation/drift/migration model at equilibrium, with homogeneous levels of local genetic diversity throughout Moroccan traditional agroecosystems. Conclusions We conclude that traditional agroecosystems constitue active incubators of varietal diversity even for clonally propagated crop species, and even when varieties correspond to clones that are often old. As only female fig is cultivated, wild fig and cultivated fig probably constitute a single evolutionary unit within these traditional agroecosystems. Core collections, however useful, are museums and hence cannot serve the same functions as traditional agroecosystems. PMID:20167055

  9. Technologies for imaging neural activity in large volumes.

    PubMed

    Ji, Na; Freeman, Jeremy; Smith, Spencer L

    2016-08-26

    Neural circuitry has evolved to form distributed networks that act dynamically across large volumes. Conventional microscopy collects data from individual planes and cannot sample circuitry across large volumes at the temporal resolution relevant to neural circuit function and behaviors. Here we review emerging technologies for rapid volume imaging of neural circuitry. We focus on two critical challenges: the inertia of optical systems, which limits image speed, and aberrations, which restrict the image volume. Optical sampling time must be long enough to ensure high-fidelity measurements, but optimized sampling strategies and point-spread function engineering can facilitate rapid volume imaging of neural activity within this constraint. We also discuss new computational strategies for processing and analyzing volume imaging data of increasing size and complexity. Together, optical and computational advances are providing a broader view of neural circuit dynamics and helping elucidate how brain regions work in concert to support behavior. PMID:27571194

  10. Restoration algorithms and system performance evaluation for active imagers

    NASA Astrophysics Data System (ADS)

    Gilles, Jérôme

    2007-10-01

    This paper deals with two fields related to active imaging system. First, we begin to explore image processing algorithms to restore the artefacts like speckle, scintillation and image dancing caused by atmospheric turbulence. Next, we examine how to evaluate the performance of this kind of systems. To do this task, we propose a modified version of the german TRM3 metric which permits to get MTF-like measures. We use the database acquired during NATO-TG40 field trials to make our tests.

  11. Modeling the target acquisition performance of active imaging systems.

    PubMed

    Espinola, Richard L; Jacobs, Eddie L; Halford, Carl E; Vollmerhausen, Richard; Tofsted, David H

    2007-04-01

    Recent development of active imaging system technology in the defense and security community have driven the need for a theoretical understanding of its operation and performance in military applications such as target acquisition. In this paper, the modeling of active imaging systems, developed at the U.S. Army RDECOM CERDEC Night Vision & Electronic Sensors Directorate, is presented with particular emphasis on the impact of coherent effects such as speckle and atmospheric scintillation. Experimental results from human perception tests are in good agreement with the model results, validating the modeling of coherent effects as additional noise sources. Example trade studies on the design of a conceptual active imaging system to mitigate deleterious coherent effects are shown. PMID:19532626

  12. Modeling the target acquisition performance of active imaging systems

    NASA Astrophysics Data System (ADS)

    Espinola, Richard L.; Jacobs, Eddie L.; Halford, Carl E.; Vollmerhausen, Richard; Tofsted, David H.

    2007-04-01

    Recent development of active imaging system technology in the defense and security community have driven the need for a theoretical understanding of its operation and performance in military applications such as target acquisition. In this paper, the modeling of active imaging systems, developed at the U.S. Army RDECOM CERDEC Night Vision & Electronic Sensors Directorate, is presented with particular emphasis on the impact of coherent effects such as speckle and atmospheric scintillation. Experimental results from human perception tests are in good agreement with the model results, validating the modeling of coherent effects as additional noise sources. Example trade studies on the design of a conceptual active imaging system to mitigate deleterious coherent effects are shown.

  13. Solar Activity Studies using Microwave Imaging Observations

    NASA Technical Reports Server (NTRS)

    Gopalswamy, N.

    2016-01-01

    We report on the status of solar cycle 24 based on polar prominence eruptions (PEs) and microwave brightness enhancement (MBE) information obtained by the Nobeyama radioheliograph. The north polar region of the Sun had near-zero field strength for more than three years (2012-2015) and ended only in September 2015 as indicated by the presence of polar PEs and the lack of MBE. The zero-polar-field condition in the south started only around 2013, but it ended by June 2014. Thus the asymmetry in the times of polarity reversal switched between cycle 23 and 24. The polar MBE is a good proxy for the polar magnetic field strength as indicated by the high degree of correlation between the two. The cross-correlation between the high- and low-latitude MBEs is significant for a lag of approximately 5.5 to 7.3 years, suggesting that the polar field of one cycle indicates the sunspot number of the next cycle in agreement with the Babcock-Leighton mechanism of solar cycles. The extended period of near-zero field in the north-polar region should result in a weak and delayed sunspot activity in the northern hemisphere in cycle 25.

  14. Olfactive detection of fig wasps as prey by the ant Crematogaster scutellaris (Formicidae; Myrmicinae).

    PubMed

    Schatz, Bertrand; Anstett, Marie-Charlotte; Out, Welmoed; Hossaert-McKey, Martine

    2003-10-01

    In the species-specific and obligate mutualism between the fig (Ficus carica) and its pollinator (the fig wasps Blastophaga psenes), a third participant, the ant Crematogaster scutellaris, is a predator of the wasps. Here, we ask how ant workers can rapidly localise such prey, whose availability is limited in time and space. Using a Y-tube olfactometer, we tested ant response to odours emitted by different types of figs (receptive female, ripe female or male figs) and by fig wasps (pollinators or non-pollinators). We demonstrate that ants were significantly attracted only to odours emitted by pollinators, either alone or associated with odours of male figs (releasing wasps). Detection of prey odour by ants is an important trait that can explain their observed high rate of predation on pollinators, and could have important implications on the stability of the fig/fig wasp mutualism. PMID:14564404

  15. The incidence and pattern of copollinator diversification in dioecious and monoecious figs

    PubMed Central

    Yang, Li-Yuan; Machado, Carlos A; Dang, Xiao-Dong; Peng, Yan-Qiong; Yang, Da-Rong; Zhang, Da-Yong; Liao, Wan-Jin

    2015-01-01

    Differences in breeding system are associated with correlated ecological and morphological changes in plants. In Ficus, dioecy and monoecy are strongly associated with different suites of traits (tree height, population density, fruiting frequency, pollinator dispersal ecology). Although approximately 30% of fig species are pollinated by multiple species of fig-pollinating wasps, it has been suggested that copollinators are rare in dioecious figs. Here, we test whether there is a connection between the fig breeding system and copollinator incidence and diversification by conducting a meta-analysis of molecular data from pollinators of 119 fig species that includes new data from 15 Asian fig species. We find that the incidence of copollinators is not significantly different between monoecious and dioecious Ficus. Surprisingly, while all copollinators in dioecious figs are sister taxa, only 32.1% in monoecious figs are sister taxa. We present hypotheses to explain those patterns and discuss their consequences on the evolution of this mutualism. PMID:25495152

  16. Sensory profiles for dried fig (Ficus carica L.) cultivars commercially grown and processed in California.

    PubMed

    Haug, Megan T; King, Ellena S; Heymann, Hildegarde; Crisosto, Carlos H

    2013-08-01

    A trained sensory panel evaluated the 6 fig cultivars currently sold in the California dried fig market. The main flavor and aroma attributes determined by the sensory panel were "caramel," "honey," "raisin," and "fig," with additional aroma attributes: "common date," "dried plum," and "molasses." Sensory differences were observed between dried fig cultivars. All figs were processed by 2 commercial handlers. Processing included potassium sorbate as a preservative and SO2 application as an antibrowning agent for white cultivars. As a consequence of SO2 use during processing, high sulfite residues affected the sensory profiles of the white dried fig cultivars. Significant differences between dried fig cultivars and sources demonstrate perceived differences between processing and storage methods. The panel-determined sensory lexicon can help with California fig marketing. PMID:23957419

  17. Research of Active Contour Model in Aerial Images

    NASA Astrophysics Data System (ADS)

    Kun, Wang; Li, Guo

    With the development of computer and aviation technology, the aerial image is facing an important issue is how to automate, including aerial images of the automatic extraction of the target. In this paper, the issue of aerial images to study the active contour model is introduced, that is, Snake model, to achieve the target aerial image of the semi-automatic contour extraction method. Snake model used the unique characteristic of the energy minimization, carried out on the image contour extraction, to obtain a clear, consistent and accurate image contour. The model is defined through the energy minimization of the function, given in the initial position of artificial circumstances, through the iterative calculation of Snake model will eventually form the minimum energy function has been described in the outline of the target partition. The results indicate that Snake model for aerial images of the edge contour extraction, verification, concluded that the Snake-based edge detection methods could be more objectively and accurately extract the edge of the outline of aerial images.

  18. Comparison of schemes for active sub-millimeter wave imaging

    NASA Astrophysics Data System (ADS)

    Furxhi, Orges; Jacobs, Eddie L.

    2011-11-01

    Various schemes for active imaging require different allocations of source power and can result in different overall signal to noise ratios. At the University of Memphis we have developed an image-plane scanning device used with a single pixel detector to form video rate images of the scene. Imaging with this device requires flood illumination of the scene. Because sub-millimeter wave sources typically produce low power, it is a common belief that flood illumination results in low detected signal power and therefore low signal to noise ratios (SNR) at the detector. In this work we quantify the SNR at the detector for our system and compare it to conventional imaging systems, conjugate point imaging systems, and focal plane array imaging. Unlike the other two systems, imaging with our device requires an additional pixel formation step; therefore, the SNR at the detector is not the per-pixel SNR. We present the limits of the per-pixel SNR and discuss its dependence on various device components.

  19. Tracking the elusive history of diversification in plant-herbivorous insect-parasitoid food webs: insights from figs and fig wasps.

    PubMed

    Kjellberg, Finn; Proffit, Magali

    2016-02-01

    The food webs consisting of plants, herbivorous insects and their insect parasitoids are a major component of terrestrial biodiversity. They play a central role in the functioning of all terrestrial ecosystems, and the number of species involved is mind-blowing (Nyman et al. 2015). Nevertheless, our understanding of the evolutionary and ecological determinants of their diversity is still in its infancy. In this issue of Molecular Ecology, Sutton et al. (2016) open a window into the comparative analysis of spatial genetic structuring in a set of comparable multitrophic models, involving highly species-specific interactions: figs and fig wasps. This is the first study to compare genetic structure using population genetics tools in a fig-pollinating wasp (Pleistodontes imperialis sp1) and its main parasitoid (Sycoscapter sp.A). The fig-pollinating wasp has a discontinuous spatial distribution that correlates with genetic differentiation, while the parasitoid bridges the discontinuity by parasitizing other pollinator species on the same host fig tree and presents basically no spatial genetic structure. The full implications of these results for our general understanding of plant-herbivorous insect-insect parasitoids diversification become apparent when envisioned within the framework of recent advances in fig and fig wasp biology. PMID:26876231

  20. Molecular Imaging of Activated Platelets Allows the Detection of Pulmonary Embolism with Magnetic Resonance Imaging

    PubMed Central

    Heidt, Timo; Ehrismann, Simon; Hövener, Jan-Bernd; Neudorfer, Irene; Hilgendorf, Ingo; Reisert, Marco; Hagemeyer, Christoph E.; Zirlik, Andreas; Reinöhl, Jochen; Bode, Christoph; Peter, Karlheinz; von Elverfeldt, Dominik; von zur Muhlen, Constantin

    2016-01-01

    Early and reliable detection of pulmonary embolism (PE) is critical for improving patient morbidity and mortality. The desire for low-threshold screening for pulmonary embolism is contradicted by unfavorable radiation of currently used computed tomography or nuclear techniques, while standard magnetic resonance imaging still struggles to provide sufficient diagnostic sensitivity in the lung. In this study we evaluate a molecular-targeted contrast agent against activated platelets for non-invasive detection of murine pulmonary thromboembolism using magnetic resonance imaging. By intravenous injection of human thrombin, pulmonary thromboembolism were consistently induced as confirmed by immunohistochemistry of the lung. Magnetic resonance imaging after thrombin injection showed local tissue edema in weighted images which co-localized with the histological presence of pulmonary thromboembolism. Furthermore, injection of a functionalized contrast agent targeting activated platelets provided sensitive evidence of focal accumulation of activated platelets within the edematous area, which, ex vivo, correlated well with the size of the pulmonary embolism. In summary, we here show delivery and specific binding of a functionalized molecular contrast agent against activated platelets for targeting pulmonary thromboembolism. Going forward, molecular imaging may provide new opportunities to increase sensitivity of magnetic resonance imaging for detection of pulmonary embolism. PMID:27138487

  1. Molecular Imaging of Activated Platelets Allows the Detection of Pulmonary Embolism with Magnetic Resonance Imaging.

    PubMed

    Heidt, Timo; Ehrismann, Simon; Hövener, Jan-Bernd; Neudorfer, Irene; Hilgendorf, Ingo; Reisert, Marco; Hagemeyer, Christoph E; Zirlik, Andreas; Reinöhl, Jochen; Bode, Christoph; Peter, Karlheinz; von Elverfeldt, Dominik; von Zur Muhlen, Constantin

    2016-01-01

    Early and reliable detection of pulmonary embolism (PE) is critical for improving patient morbidity and mortality. The desire for low-threshold screening for pulmonary embolism is contradicted by unfavorable radiation of currently used computed tomography or nuclear techniques, while standard magnetic resonance imaging still struggles to provide sufficient diagnostic sensitivity in the lung. In this study we evaluate a molecular-targeted contrast agent against activated platelets for non-invasive detection of murine pulmonary thromboembolism using magnetic resonance imaging. By intravenous injection of human thrombin, pulmonary thromboembolism were consistently induced as confirmed by immunohistochemistry of the lung. Magnetic resonance imaging after thrombin injection showed local tissue edema in weighted images which co-localized with the histological presence of pulmonary thromboembolism. Furthermore, injection of a functionalized contrast agent targeting activated platelets provided sensitive evidence of focal accumulation of activated platelets within the edematous area, which, ex vivo, correlated well with the size of the pulmonary embolism. In summary, we here show delivery and specific binding of a functionalized molecular contrast agent against activated platelets for targeting pulmonary thromboembolism. Going forward, molecular imaging may provide new opportunities to increase sensitivity of magnetic resonance imaging for detection of pulmonary embolism. PMID:27138487

  2. Experiences from long range passive and active imaging

    NASA Astrophysics Data System (ADS)

    Grönwall, Christina; Gustafsson, David; Steinvall, Ove; Tolt, Gustav

    2015-10-01

    We present algorithm evaluations for ATR of small sea vessels. The targets are at km distance from the sensors, which means that the algorithms have to deal with images affected by turbulence and mirage phenomena. We evaluate previously developed algorithms for registration of 3D-generating laser radar data. The evaluations indicate that some robustness to turbulence and mirage induced uncertainties can be handled by our probabilistic-based registration method. We also assess methods for target classification and target recognition on these new 3D data. An algorithm for detecting moving vessels in infrared image sequences is presented; it is based on optical flow estimation. Detection of moving target with an unknown spectral signature in a maritime environment is a challenging problem due to camera motion, background clutter, turbulence and the presence of mirage. First, the optical flow caused by the camera motion is eliminated by estimating the global flow in the image. Second, connected regions containing significant motions that differ from camera motion is extracted. It is assumed that motion caused by a moving vessel is more temporally stable than motion caused by mirage or turbulence. Furthermore, it is assumed that the motion caused by the vessel is more homogenous with respect to both magnitude and orientation, than motion caused by mirage and turbulence. Sufficiently large connected regions with a flow of acceptable magnitude and orientation are considered target regions. The method is evaluated on newly collected sequences of SWIR and MWIR images, with varying targets, target ranges and background clutter. Finally we discuss a concept for combining passive and active imaging in an ATR process. The main steps are passive imaging for target detection, active imaging for target/background segmentation and a fusion of passive and active imaging for target recognition.

  3. Yeasts isolated from figs (Ficus carica L.) as biocontrol agents of postharvest fruit diseases.

    PubMed

    Ruiz-Moyano, S; Martín, A; Villalobos, M C; Calle, A; Serradilla, M J; Córdoba, M G; Hernández, A

    2016-08-01

    Fresh fruit is highly perishable during postharvest life, mainly due to fungal growth. Thus, fungal control is an important goal for the fruit industry. In this work, a selection of antagonistic yeasts isolated from fig and breba crops were screened in vitro. The isolated yeasts were challenged with three moulds isolated from decayed figs and breba crops, identified as Penicillium expansum M639 and Cladosporium cladosporioides M310 and M624, and pathogenic moulds Botrytis cinerea CECT20518 and Monilia laxa CA1 from culture collections. Two yeast isolates, Hanseniaspora opuntiae L479 and Metschnikowia pulcherrima L672, were selected for their ability to inhibit the growth of aforementioned moulds. These yeasts reduced the radial growth of moulds on PDA by between 45.23% and 66.09%. Antagonistic activity was associated with the interaction of live yeast cells with moulds. M. pulcherrima L672 apparently parasitised C. cladosporioides isolates. In addition, challenges were assayed using wounded apples and nectarines, with significant reductions in percent infection and lesion size for all moulds tested. To our knowledge, this is the first report identifying H. opuntiae as an antagonist against different pathogenic moulds. PMID:27052701

  4. Noninvasive Molecular Imaging of Disease Activity in Atherosclerosis.

    PubMed

    Dweck, Marc R; Aikawa, Elena; Newby, David E; Tarkin, Jason M; Rudd, James H F; Narula, Jagat; Fayad, Zahi A

    2016-07-01

    Major focus has been placed on the identification of vulnerable plaques as a means of improving the prediction of myocardial infarction. However, this strategy has recently been questioned on the basis that the majority of these individual coronary lesions do not in fact go on to cause clinical events. Attention is, therefore, shifting to alternative imaging modalities that might provide a more complete pan-coronary assessment of the atherosclerotic disease process. These include markers of disease activity with the potential to discriminate between patients with stable burnt-out disease that is no longer metabolically active and those with active atheroma, faster disease progression, and increased risk of infarction. This review will examine how novel molecular imaging approaches can provide such assessments, focusing on inflammation and microcalcification activity, the importance of these processes to coronary atherosclerosis, and the advantages and challenges posed by these techniques. PMID:27390335

  5. Active imaging system performance model for target acquisition

    NASA Astrophysics Data System (ADS)

    Espinola, Richard L.; Teaney, Brian; Nguyen, Quang; Jacobs, Eddie L.; Halford, Carl E.; Tofsted, David H.

    2007-04-01

    The U.S. Army RDECOM CERDEC Night Vision & Electronic Sensors Directorate has developed a laser-range-gated imaging system performance model for the detection, recognition, and identification of vehicle targets. The model is based on the established US Army RDECOM CERDEC NVESD sensor performance models of the human system response through an imaging system. The Java-based model, called NVLRG, accounts for the effect of active illumination, atmospheric attenuation, and turbulence effects relevant to LRG imagers, such as speckle and scintillation, and for the critical sensor and display components. This model can be used to assess the performance of recently proposed active SWIR systems through various trade studies. This paper will describe the NVLRG model in detail, discuss the validation of recent model components, present initial trade study results, and outline plans to validate and calibrate the end-to-end model with field data through human perception testing.

  6. Imaging an Active Volcano Edifice at Tenerife Island, Spain

    NASA Astrophysics Data System (ADS)

    Ibáñez, Jesús M.; Rietbrock, Andreas; García-Yeguas, Araceli

    2008-08-01

    An active seismic experiment to study the internal structure of Teide volcano is being carried out on Tenerife, a volcanic island in Spain's Canary Islands archipelago. The main objective of the Tomography at Teide Volcano Spain (TOM-TEIDEVS) experiment, begun in January 2007, is to obtain a three-dimensional (3-D) structural image of Teide volcano using seismic tomography and seismic reflection/refraction imaging techniques. At present, knowledge of the deeper structure of Teide and Tenerife is very limited, with proposed structural models based mainly on sparse geophysical and geological data. The multinational experiment-involving institutes from Spain, the United Kingdom, Italy, Ireland, and Mexico-will generate a unique high-resolution structural image of the active volcano edifice and will further our understanding of volcanic processes.

  7. Linear and non-linear fluorescence imaging of neuronal activity

    NASA Astrophysics Data System (ADS)

    Fisher, Jonathan A. N.

    Optical imaging of neuronal activity offers new possibilities for understanding brain physiology. The predominant methods in neuroscience for measuring electrical activity require electrodes inserted into the tissue. Such methods, however, provide limited spatial information and are invasive. Optical methods are less physically invasive and offer the possibility for simultaneously imaging the activity of many neurons. In this thesis one- and two-photon fluorescence microscopy techniques were applied to several in vivo and in vitro mammalian preparations. Using one-photon absorption fluorescence microscopy and gradient index (GRIN) lens optics, cortical electrical activity in response to electric stimulation was resolved in three-dimensions at high-speed in the primary somatosensory cortex of the mouse in vivo using voltage-sensitive dyes. Imaging at depths up to 150 mum below the cortex surface, it was possible to resolve depth-dependent patterns of neuronal activity in response to cortical and thalamic electric stimulation. The patterns of activity were consistent with known cortical cellular architecture. In a qualitatively different set of experiments, one-photon fluorescence microscopy via voltage-sensitive dyes was successfully employed to image an in vitro preparation of the perfused rat brainstem during the process of respiratory rhythmogenesis. Imaging results yielded insights into the spatial organization of the central respiratory rhythm generation region in the ventrolateral medulla. A multifocal two-photon scanning microscope was constructed, and design and operation principles are described. Utilizing the novel device, anatomical and functional two-photon imaging via potentiometric dyes and calcium dyes is described, and the results of in vivo versus in vitro imaging are compared. Anatomical imaging results used either functional probe background fluorescence or green fluorescent protein (GFP) expression. Spectroscopic experiments measuring the two

  8. Same but different: Larval development and gall-inducing process of a non-pollinating fig wasp compared to that of pollinating fig-wasps

    NASA Astrophysics Data System (ADS)

    Jansen-González, Sergio; Teixeira, Simone de Padua; Kjellberg, Finn; Pereira, Rodrigo A. Santinelo

    2014-05-01

    The receptacles of fig trees (Ficus spp.) can harbor a highly diversified and complex community of chalcid wasps. Functional groups of fig wasps (e.g. gallers, cleptoparasites and parasitoids) oviposit into the fig at different developmental stages, reflecting different feeding regimes for these insect larvae. There are few direct data available on larval feeding regimes and access to resources. We studied the gall induction and larval feeding strategy of an Idarnes (group flavicollis) species, a non-pollinating fig wasp (NPFW) associated to Ficus citrifolia P. Miller in Brazil. This Idarnes species shares with the pollinator characteristics such as time of oviposition, ovipositor insertion through flower and location of the egg inside plant ovaries. Nevertheless, we show that the gall induction differs considerably from that of the pollinating species. This Idarnes species relies on the induction of nucellus cell proliferation for gall formation and as the main larval resource. This strategy enables it to develop in both pollinated and unpollinated figs. The large differences between this NPFW and other fig wasps in how ovules are galled suggest that there are different ways to be a galler. A functional analysis of NPFW community structure may require descriptions of the histological processes associated with larval development.

  9. Multiple Horizontal Transfers of Bacteriophage WO and Host Wolbachia in Fig Wasps in a Closed Community

    PubMed Central

    Wang, Ningxin; Jia, Sisi; Xu, Heng; Liu, Yong; Huang, Dawei

    2016-01-01

    Wolbachia-bacteriophage WO is a good model system for studying interactions between bacteria and viruses. Previous surveys of insect hosts have been conducted via sampling from open or semi-open communities; however, no studies have reported the infection patterns of phage WO of insects living in a closed community. Figs and fig wasps form a peculiar closed community in which the Ficus tree provides a compact syconium habitat for a variety of fig wasp. Therefore, in this study, we performed a thorough survey of Wolbachia and bacteriophage WO infection patterns in a total of 1406 individuals from 23 fig wasps species living on three different fig tree species. The infection rates of Wolbachia and phage WO were 82.6% (19/23) and 39.1% (9/23), respectively. Additionally, phage WO from fig wasps showed strong insect host specificity based on orf7 sequences from fig wasps and 21 other insect species. Probably due to the physical barrier of fig syconium, most phage WO from fig wasps form a specific clade. Phylogenetic analysis showed the absence of congruence between WO and host Wolbachia, WO and insect host, as well as Wolbachia and fig wasps, suggesting that both Wolbachia and phage WO exchanged frequently and independently within the closed syconium. Thus, the infection pattern of bacteriophage WO from fig wasps appeared quite different from that in other insects living outside, although the effect and the transfer routes of phage WO are unclear, which need to be investigated in the future. PMID:26913026

  10. Multiple Horizontal Transfers of Bacteriophage WO and Host Wolbachia in Fig Wasps in a Closed Community.

    PubMed

    Wang, Ningxin; Jia, Sisi; Xu, Heng; Liu, Yong; Huang, Dawei

    2016-01-01

    Wolbachia-bacteriophage WO is a good model system for studying interactions between bacteria and viruses. Previous surveys of insect hosts have been conducted via sampling from open or semi-open communities; however, no studies have reported the infection patterns of phage WO of insects living in a closed community. Figs and fig wasps form a peculiar closed community in which the Ficus tree provides a compact syconium habitat for a variety of fig wasp. Therefore, in this study, we performed a thorough survey of Wolbachia and bacteriophage WO infection patterns in a total of 1406 individuals from 23 fig wasps species living on three different fig tree species. The infection rates of Wolbachia and phage WO were 82.6% (19/23) and 39.1% (9/23), respectively. Additionally, phage WO from fig wasps showed strong insect host specificity based on orf7 sequences from fig wasps and 21 other insect species. Probably due to the physical barrier of fig syconium, most phage WO from fig wasps form a specific clade. Phylogenetic analysis showed the absence of congruence between WO and host Wolbachia, WO and insect host, as well as Wolbachia and fig wasps, suggesting that both Wolbachia and phage WO exchanged frequently and independently within the closed syconium. Thus, the infection pattern of bacteriophage WO from fig wasps appeared quite different from that in other insects living outside, although the effect and the transfer routes of phage WO are unclear, which need to be investigated in the future. PMID:26913026

  11. Ancient and modern occurrences of common fig (Ficus carica L.) in the British isles

    NASA Astrophysics Data System (ADS)

    Dickson, James H.; Dickson, Camilla

    Knowledge of the reproductive biology of the common fig ( Ficus carica) is essential for the interpretation of present and past occurrences of pips from archaeological layers as well as for understanding the status of trees, cultivated or wild. Only parthenocarpic varieties ripen figs in Britain and these cannot produce fertile pips. Common figs growing wild in Britain all come from pips from imported figs, often figs that had been eaten and the pips evacuated. There are many discoveries of pips from Roman and later urban and military sites in Britain. These pips too were derived from imported figs and not from locally cultivated trees. There is no proof that the Romans grew common fig in Britain and the earliest documentary evidence of cultivation is as late as the 15th century A.D.

  12. A CMOS Energy Harvesting and Imaging (EHI) Active Pixel Sensor (APS) Imager for Retinal Prosthesis.

    PubMed

    Ay, S U

    2011-12-01

    A CMOS image sensor capable of imaging and energy harvesting on same focal plane is presented for retinal prosthesis. The energy harvesting and imaging (EHI) active pixel sensor (APS) imager was designed, fabricated, and tested in a standard 0.5 μm CMOS process. It has 54 × 50 array of 21 × 21 μm(2) EHI pixels, 10-bit supply boosted (SB) SAR ADC, and charge pump circuits consuming only 14.25 μW from 1.2 V and running at 7.4 frames per second. The supply boosting technique (SBT) is used in an analog signal chain of the EHI imager. Harvested solar energy on focal plane is stored on an off-chip capacitor with the help of a charge pump circuit with better than 70% efficiency. Energy harvesting efficiency of the EHI pixel was measured at different light levels. It was 9.4% while producing 0.41 V open circuit voltage. The EHI imager delivers 3.35 μW of power was delivered to a resistive load at maximum power point operation. The measured pixel array figure of merit (FoM) was 1.32 pW/frame/pixel while imager figure of merit (iFoM) including whole chip power consumption was 696 fJ/pixel/code for the EHI imager. PMID:23852551

  13. Active spectral imaging for standoff detection of explosives

    SciTech Connect

    Skvortsov, L A

    2011-12-31

    Laser methods of standoff detection of explosive traces on surfaces of objects are considered. These methods are based on active formation of multi- and hyperspectral images of an object examined. The possibilities of these methods and the prospects of their development are discussed. Emphasis is laid on the justification of the most preferred field of application of the technique under consideration.

  14. Browsing Image Collections with Representations of Common-Sense Activities.

    ERIC Educational Resources Information Center

    Gordon, Andrew S.

    2001-01-01

    Describes a methodology for creating networks of subject terms by manually representing a large number of common-sense activities that are broadly related to image subject terms. Application of this methodology to the Library of Congress Thesaurus for Graphic Materials produced 768 representations that supported users of a prototype browsing-based…

  15. Research on range-gated laser active imaging seeker

    NASA Astrophysics Data System (ADS)

    You, Mu; Wang, PengHui; Tan, DongJie

    2013-09-01

    Compared with other imaging methods such as millimeter wave imaging, infrared imaging and visible light imaging, laser imaging provides both a 2-D array of reflected intensity data as well as 2-D array of range data, which is the most important data for use in autonomous target acquisition .In terms of application, it can be widely used in military fields such as radar, guidance and fuse. In this paper, we present a laser active imaging seeker system based on range-gated laser transmitter and sensor technology .The seeker system presented here consist of two important part, one is laser image system, which uses a negative lens to diverge the light from a pulse laser to flood illuminate a target, return light is collected by a camera lens, each laser pulse triggers the camera delay and shutter. The other is stabilization gimbals, which is designed to be a rotatable structure both in azimuth and elevation angles. The laser image system consists of transmitter and receiver. The transmitter is based on diode pumped solid-state lasers that are passively Q-switched at 532nm wavelength. A visible wavelength was chosen because the receiver uses a Gen III image intensifier tube with a spectral sensitivity limited to wavelengths less than 900nm.The receiver is image intensifier tube's micro channel plate coupled into high sensitivity charge coupled device camera. The image has been taken at range over one kilometer and can be taken at much longer range in better weather. Image frame frequency can be changed according to requirement of guidance with modifiable range gate, The instantaneous field of views of the system was found to be 2×2 deg. Since completion of system integration, the seeker system has gone through a series of tests both in the lab and in the outdoor field. Two different kinds of buildings have been chosen as target, which is located at range from 200m up to 1000m.To simulate dynamic process of range change between missile and target, the seeker system has

  16. Deep mtDNA divergences indicate cryptic species in a fig-pollinating wasp

    PubMed Central

    Haine, Eleanor R; Martin, Joanne; Cook, James M

    2006-01-01

    Background Figs and fig-pollinating wasps are obligate mutualists that have coevolved for ca 90 million years. They have radiated together, but do not show strict cospeciation. In particular, it is now clear that many fig species host two wasp species, so there is more wasp speciation than fig speciation. However, little is known about how fig wasps speciate. Results We studied variation in 71 fig-pollinating wasps from across the large geographic range of Ficus rubiginosa in Australia. All wasps sampled belong to one morphological species (Pleistodontes imperialis), but we found four deep mtDNA clades that differed from each other by 9–17% nucleotides. As these genetic distances exceed those normally found within species and overlap those (10–26%) found between morphologically distinct Pleistodontes species, they strongly suggest cryptic fig wasp species. mtDNA clade diversity declines from all four present in Northern Queensland to just one in Sydney, near the southern range limit. However, at most sites multiple clades coexist and can be found in the same tree or even the same fig fruit and there is no evidence for parallel sub-division of the host fig species. Both mtDNA data and sequences from two nuclear genes support the monophyly of the "P. imperialis complex" relative to other Pleistodontes species, suggesting that fig wasp divergence has occurred without any host plant shift. Wasps in clade 3 were infected by a single strain (W1) of Wolbachia bacteria, while those in other clades carried a double infection (W2+W3) of two other strains. Conclusion Our study indicates that cryptic fig-pollinating wasp species have developed on a single host plant species, without the involvement of host plant shifts, or parallel host plant divergence. Despite extensive evidence for coevolution between figs and fig wasps, wasp speciation may not always be linked strongly with fig speciation. PMID:17040562

  17. Diffuse optical imaging of brain activation to joint attention experience.

    PubMed

    Zhu, Banghe; Yadav, Nitin; Rey, Gustavo; Godavarty, Anuradha

    2009-08-24

    In the early development of social cognition and language, infants tend to participate in face-to-face interactions engaging in joint attention exchanges. Joint attention is vital to social competence at all ages, lacking which is a primary feature to distinguish autistic from non-autistic population. In this study, diffuse optical imaging is used for the first time to investigate the joint attention experience in normal adults. Imaging studies were performed in the frontal regions of the brain (BA9 and BA10) in order to study the differences in the brain activation in response to video clips corresponding to joint attention based skills. The frontal regions of the brain were non-invasively imaged using a novel optical cap coupled to a frequency-domain optical imaging system. The statistical analysis from 11 normal adult subjects, with three repetitions from each subject, indicated that the averaged changes in the cerebral blood oxygenation levels were different under the joint and non-joint attention based stimulus. The preliminary studies demonstrate the feasibility of implementing diffuse optical imaging towards autism-related research to study the brain activation in response to socio-communication skills. PMID:19447278

  18. AMISS - Active and passive MIcrowaves for Security and Subsurface imaging

    NASA Astrophysics Data System (ADS)

    Soldovieri, Francesco; Slob, Evert; Turk, Ahmet Serdar; Crocco, Lorenzo; Catapano, Ilaria; Di Matteo, Francesca

    2013-04-01

    The FP7-IRSES project AMISS - Active and passive MIcrowaves for Security and Subsurface imaging is based on a well-combined network among research institutions of EU, Associate and Third Countries (National Research Council of Italy - Italy, Technische Universiteit Delft - The Netherlands, Yildiz Technical University - Turkey, Bauman Moscow State Technical University - Russia, Usikov Institute for Radio-physics and Electronics and State Research Centre of Superconductive Radioelectronics "Iceberg" - Ukraine and University of Sao Paulo - Brazil) with the aims of achieving scientific advances in the framework of microwave and millimeter imaging systems and techniques for security and safety social issues. In particular, the involved partners are leaders in the scientific areas of passive and active imaging and are sharing their complementary knowledge to address two main research lines. The first one regards the design, characterization and performance evaluation of new passive and active microwave devices, sensors and measurement set-ups able to mitigate clutter and increase information content. The second line faces the requirements to make State-of-the-Art processing tools compliant with the instrumentations developed in the first line, suitable to work in electromagnetically complex scenarios and able to exploit the unexplored possibilities offered by new instrumentations. The main goals of the project are: 1) Development/improvement and characterization of new sensors and systems for active and passive microwave imaging; 2) Set up, analysis and validation of state of art/novel data processing approach for GPR in critical infrastructure and subsurface imaging; 3) Integration of state of art and novel imaging hardware and characterization approaches to tackle realistic situations in security, safety and subsurface prospecting applications; 4) Development and feasibility study of bio-radar technology (system and data processing) for vital signs detection and

  19. Autolysis control and structural changes of purified ficin from Iranian fig latex with synthetic inhibitors.

    PubMed

    Zare, H; Moosavi-Movahedi, A A; Salami, M; Sheibani, N; Khajeh, K; Habibi-Rezaei, M

    2016-03-01

    The fig's ficin is a cysteine endoproteolytic enzyme, which plays fundamental roles in many plant physiological processes, and has many applications in different industries such as pharmaceutical and food. In this work, we report the inhibition and activation of autolysis and structural changes associated with reaction of ficin with iodoacetamide and tetrathionate using high-performance liquid chromatography (HPLC), ultra filtration membrane, and dynamic light scattering (DLS) methods. The ficin structural changes were also determined using UV-absorption, circular dichroism (CD), fluorescence spectroscopy, and differential scanning calorimetry (DSC) techniques. These techniques demonstrated that iodoacetamide completely inhibited ficin autolysis, which was irreversible. However, tetrathionate partially and reversibility inhibited its autolysis. The ficin structural changes with two synthetic inhibitors were associated with secondary structural changes related to decreased alpha-helix and increased beta sheet and random coil conformations, contributing to its aggregation. PMID:26718871

  20. Multilevel depth and image fusion for human activity detection.

    PubMed

    Ni, Bingbing; Pei, Yong; Moulin, Pierre; Yan, Shuicheng

    2013-10-01

    Recognizing complex human activities usually requires the detection and modeling of individual visual features and the interactions between them. Current methods only rely on the visual features extracted from 2-D images, and therefore often lead to unreliable salient visual feature detection and inaccurate modeling of the interaction context between individual features. In this paper, we show that these problems can be addressed by combining data from a conventional camera and a depth sensor (e.g., Microsoft Kinect). We propose a novel complex activity recognition and localization framework that effectively fuses information from both grayscale and depth image channels at multiple levels of the video processing pipeline. In the individual visual feature detection level, depth-based filters are applied to the detected human/object rectangles to remove false detections. In the next level of interaction modeling, 3-D spatial and temporal contexts among human subjects or objects are extracted by integrating information from both grayscale and depth images. Depth information is also utilized to distinguish different types of indoor scenes. Finally, a latent structural model is developed to integrate the information from multiple levels of video processing for an activity detection. Extensive experiments on two activity recognition benchmarks (one with depth information) and a challenging grayscale + depth human activity database that contains complex interactions between human-human, human-object, and human-surroundings demonstrate the effectiveness of the proposed multilevel grayscale + depth fusion scheme. Higher recognition and localization accuracies are obtained relative to the previous methods. PMID:23996589

  1. Pollinator sharing and gene flow among closely related sympatric dioecious fig taxa.

    PubMed

    Wang, Gang; Cannon, Charles H; Chen, Jin

    2016-04-13

    Hybridization and insect pollination are widely believed to increase rates of plant diversification. The extreme diversity of figs (Ficus) and their obligate pollinators, fig wasps (Agaonidae), provides an opportunity to examine the possible role of pollinator-mediated hybridization in plant diversification. Increasing evidence suggests that pollinator sharing and hybridization occurs among fig taxa, despite relatively strict coevolution with the pollinating wasp. Using five sympatric dioecious fig taxa and their pollinators, we examine the degree of pollinator sharing and inter-taxa gene flow. We experimentally test pollinator preference for floral volatiles, the main host recognition signal, from different figs. All five fig taxa shared pollinators with other taxa, and gene flow occurred between fig taxa within and between sections. Floral volatiles of each taxon attracted more than one pollinator species. Floral volatiles were more similar between closely related figs, which experienced higher levels of pollinator sharing and inter-taxa gene flow. This study demonstrates that pollinator sharing and inter-taxa gene flow occurs among closely related sympatric dioecious fig taxa and that pollinators choose the floral volatiles of multiple fig taxa. The implications of pollinator sharing and inter-taxa gene flow on diversification, occurring even in this highly specialized obligate pollination system, require further study. PMID:27075252

  2. Image sensor innovations for low light levels with active imaging features

    NASA Astrophysics Data System (ADS)

    Powell, Gareth H.; Fereyre, Pierre

    2015-02-01

    Advances in CMOS imaging enable image capture at lower light levels. Color detection is also possible where human vision becomes less sensitive in night conditions. In daytime conditions, there are a number of climatic conditions such as rain, fog, snow or smoke etc. that render traditional `intelligent' outdoor cameras that perform various forms of detection and identification tasks relatively ineffective. It has been proven that an adapted five transistor pixel CMOS sensor can perform range-gated active imaging that extends considerably the usability of intelligent cameras in the most difficult conditions. This paper discusses advanced state of the art image sensors with embedded features, with emphasis on the everimportant size, weight, power and cost benefits and discusses the new applications that are enabled.

  3. Geodesic active fields--a geometric framework for image registration.

    PubMed

    Zosso, Dominique; Bresson, Xavier; Thiran, Jean-Philippe

    2011-05-01

    In this paper we present a novel geometric framework called geodesic active fields for general image registration. In image registration, one looks for the underlying deformation field that best maps one image onto another. This is a classic ill-posed inverse problem, which is usually solved by adding a regularization term. Here, we propose a multiplicative coupling between the registration term and the regularization term, which turns out to be equivalent to embed the deformation field in a weighted minimal surface problem. Then, the deformation field is driven by a minimization flow toward a harmonic map corresponding to the solution of the registration problem. This proposed approach for registration shares close similarities with the well-known geodesic active contours model in image segmentation, where the segmentation term (the edge detector function) is coupled with the regularization term (the length functional) via multiplication as well. As a matter of fact, our proposed geometric model is actually the exact mathematical generalization to vector fields of the weighted length problem for curves and surfaces introduced by Caselles-Kimmel-Sapiro. The energy of the deformation field is measured with the Polyakov energy weighted by a suitable image distance, borrowed from standard registration models. We investigate three different weighting functions, the squared error and the approximated absolute error for monomodal images, and the local joint entropy for multimodal images. As compared to specialized state-of-the-art methods tailored for specific applications, our geometric framework involves important contributions. Firstly, our general formulation for registration works on any parametrizable, smooth and differentiable surface, including nonflat and multiscale images. In the latter case, multiscale images are registered at all scales simultaneously, and the relations between space and scale are intrinsically being accounted for. Second, this method is, to

  4. Three-dimensional active imaging using compressed gating

    NASA Astrophysics Data System (ADS)

    Dai, Huidong; He, Weiji; Miao, Zhuang; Chen, Yunfei; Gu, Guohua

    2013-09-01

    Due to the numerous applications employed 3D data such as target detection and recognition, three-dimensional (3D) active imaging draws great interest recently. Employing a pulsed laser as the illumination source and an intensified sensor as the image sensor, the 3D active imaging method emits and then records laser pulses to infer the distance between the target and the sensor. One of the limitations of the 3D active imaging is that acquiring depth map with high depth resolution requires a full range sweep, as well as a large number of detections, which limits the detection speed. In this work, a compressed gating method combining the 3D active imaging and compressive sensing (CS) is proposed on the basis of the random gating method to achieve the depth map reconstruction from a significantly reduced number of detections. Employing random sequences to control the sensor gate, this method estimates the distance and reconstructs the depth map in the framework of CS. A simulation was carried out to estimate the performance of the proposed method. A scene generated by the 3ds Max was employed as target and a reconstruction algorithm was used to recover the depth map in the simulation. The simulation results have shown that the proposed method can reconstruct the depth map with slight reconstruction error using as low as 7% detections that the conventional method requires and achieve perfect reconstruction from about 10% detections under the same depth resolution. It has also indicated that the number of detections required is affected by depth resolution, noise generated by a variety of reasons and complexity of the target scene. According to the simulation results, the compressed gating method is able to be used in the case of long range with high depth resolution and robust to various types of noise. In addition, the method is able to be used for multiple-return signals measurement without increase in the number of detections.

  5. Simultaneous reconstruction of the activity image and registration of the CT image in TOF-PET

    NASA Astrophysics Data System (ADS)

    Rezaei, Ahmadreza; Michel, Christian; Casey, Michael E.; Nuyts, Johan

    2016-02-01

    Previously, maximum-likelihood methods have been proposed to jointly estimate the activity image and the attenuation image or the attenuation sinogram from time-of-flight (TOF) positron emission tomography (PET) data. In this contribution, we propose a method that addresses the possible alignment problem of the TOF-PET emission data and the computed tomography (CT) attenuation data, by combining reconstruction and registration. The method, called MLRR, iteratively reconstructs the activity image while registering the available CT-based attenuation image, so that the pair of activity and attenuation images maximise the likelihood of the TOF emission sinogram. The algorithm is slow to converge, but some acceleration could be achieved by using Nesterov’s momentum method and by applying a multi-resolution scheme for the non-rigid displacement estimation. The latter also helps to avoid local optima, although convergence to the global optimum cannot be guaranteed. The results are evaluated on 2D and 3D simulations as well as a respiratory gated clinical scan. Our experiments indicate that the proposed method is able to correct for possible misalignment of the CT-based attenuation image, and is therefore a very promising approach to suppressing attenuation artefacts in clinical PET/CT. When applied to respiratory gated data of a patient scan, it produced deformations that are compatible with breathing motion and which reduced the well known attenuation artefact near the dome of the liver. Since the method makes use of the energy-converted CT attenuation image, the scale problem of joint reconstruction is automatically solved.

  6. Segmentation of intensity inhomogeneous brain MR images using active contours.

    PubMed

    Akram, Farhan; Kim, Jeong Heon; Lim, Han Ul; Choi, Kwang Nam

    2014-01-01

    Segmentation of intensity inhomogeneous regions is a well-known problem in image analysis applications. This paper presents a region-based active contour method for image segmentation, which properly works in the context of intensity inhomogeneity problem. The proposed region-based active contour method embeds both region and gradient information unlike traditional methods. It contains mainly two terms, area and length, in which the area term practices a new region-based signed pressure force (SPF) function, which utilizes mean values from a certain neighborhood using the local binary fitted (LBF) energy model. In turn, the length term uses gradient information. The novelty of our method is to locally compute new SPF function, which uses local mean values and is able to detect boundaries of the homogenous regions. Finally, a truncated Gaussian kernel is used to regularize the level set function, which not only regularizes it but also removes the need of computationally expensive reinitialization. The proposed method targets the segmentation problem of intensity inhomogeneous images and reduces the time complexity among locally computed active contour methods. The experimental results show that the proposed method yields better segmentation result as well as less time complexity compared with the state-of-the-art active contour methods. PMID:25143780

  7. Caprine herpesvirus 1 (CpHV-1) vaginal infection of goats: clinical efficacy of fig latex.

    PubMed

    Camero, Michele; Marinaro, Mariarosaria; Losurdo, Michele; Larocca, Vittorio; Bodnar, Livia; Patruno, Giovanni; Buonavoglia, Canio; Tempesta, Maria

    2016-01-01

    The latex of Ficus carica Linn. (Moraceae) has been shown to interfere with the replication of caprine herpesvirus (CpHV)-1 in vitro. The present study was undertaken to determine the efficacy of vaginal administration of fig latex in goats experimentally infected with CpHV-1. The fig latex reduced the clinical signs of the herpetic disease although it slightly influenced the titres of CpHV-1 shed. Thus, the fig latex maintained a partial efficacy in vivo. PMID:25835328

  8. Simultaneous water activation and glucose metabolic rate imaging with PET

    NASA Astrophysics Data System (ADS)

    Verhaeghe, Jeroen; Reader, Andrew J.

    2013-02-01

    A novel imaging and signal separation strategy is proposed to be able to separate [18F]FDG and multiple [15O]H2O signals from a simultaneously acquired dynamic PET acquisition of the two tracers. The technique is based on the fact that the dynamics of the two tracers are very distinct. By adopting an appropriate bolus injection strategy and by defining tailored sets of basis functions that model either the FDG or water component, it is possible to separate the FDG and water signal. The basis functions are inspired from the spectral analysis description of dynamic PET studies and are defined as the convolution of estimated generating functions (GFs) with a set of decaying exponential functions. The GFs are estimated from the overall measured head curve, while the decaying exponential functions are pre-determined. In this work, the time activity curves (TACs) are modelled post-reconstruction but the model can be incorporated in a global 4D reconstruction strategy. Extensive PET simulation studies are performed considering single [18F]FDG and 6 [15O]H2O bolus injections for a total acquisition time of 75 min. The proposed method is evaluated at multiple noise levels and different parameters were estimated such as [18F]FDG uptake and blood flow estimated from the [15O]H2O component, requiring a full dynamic analysis of the two components, static images of [18F]FDG and the water components as well as [15O]H2O activation. It is shown that the resulting images and parametric values in ROIs are comparable to images obtained from separate imaging, illustrating the feasibility of simultaneous imaging of [18F]FDG and [15O]H2O components. For more information on this article, see medicalphysicsweb.org

  9. Radio Imaging Observations of Solar Activity Cycle and Its Anomaly

    NASA Astrophysics Data System (ADS)

    Shibasaki, K.

    2011-12-01

    The 24th solar activity cycle has started and relative sunspot numbers are increasing. However, their rate of increase is rather slow compared to previous cycles. Active region sizes are small, lifetime is short, and big (X-class) flares are rare so far. We study this anomalous situation using data from Nobeyama Radioheliograph (NoRH). Radio imaging observations have been done by NoRH since 1992. Nearly 20 years of daily radio images of the Sun at 17 GHz are used to synthesize a radio butterfly diagram. Due to stable operation of the instrument and a robust calibration method, uniform datasets are available covering the whole period of observation. The radio butterfly diagram shows bright features corresponding to active region belts and their migration toward low latitude as the solar cycle progresses. In the present solar activity cycle (24), increase of radio brightness is delayed and slow. There are also bright features around both poles (polar brightening). Their brightness show solar cycle dependence but peaks around solar minimum. Comparison between the last minimum and the previous one shows decrease of its brightness. This corresponds to weakening of polar magnetic field activity between them. In the northern pole, polar brightening is already weakened in 2011, which means it is close to solar maximum in the northern hemisphere. Southern pole does not show such feature yet. Slow rise of activity in active region belt, weakening of polar activity during the minimum, and large north-south asymmetry in polar activity imply that global solar activity and its synchronization are weakening.

  10. Sensitive red protein calcium indicators for imaging neural activity

    PubMed Central

    Dana, Hod; Mohar, Boaz; Sun, Yi; Narayan, Sujatha; Gordus, Andrew; Hasseman, Jeremy P; Tsegaye, Getahun; Holt, Graham T; Hu, Amy; Walpita, Deepika; Patel, Ronak; Macklin, John J; Bargmann, Cornelia I; Ahrens, Misha B; Schreiter, Eric R; Jayaraman, Vivek; Looger, Loren L; Svoboda, Karel; Kim, Douglas S

    2016-01-01

    Genetically encoded calcium indicators (GECIs) allow measurement of activity in large populations of neurons and in small neuronal compartments, over times of milliseconds to months. Although GFP-based GECIs are widely used for in vivo neurophysiology, GECIs with red-shifted excitation and emission spectra have advantages for in vivo imaging because of reduced scattering and absorption in tissue, and a consequent reduction in phototoxicity. However, current red GECIs are inferior to the state-of-the-art GFP-based GCaMP6 indicators for detecting and quantifying neural activity. Here we present improved red GECIs based on mRuby (jRCaMP1a, b) and mApple (jRGECO1a), with sensitivity comparable to GCaMP6. We characterized the performance of the new red GECIs in cultured neurons and in mouse, Drosophila, zebrafish and C. elegans in vivo. Red GECIs facilitate deep-tissue imaging, dual-color imaging together with GFP-based reporters, and the use of optogenetics in combination with calcium imaging. DOI: http://dx.doi.org/10.7554/eLife.12727.001 PMID:27011354

  11. Sensitive red protein calcium indicators for imaging neural activity.

    PubMed

    Dana, Hod; Mohar, Boaz; Sun, Yi; Narayan, Sujatha; Gordus, Andrew; Hasseman, Jeremy P; Tsegaye, Getahun; Holt, Graham T; Hu, Amy; Walpita, Deepika; Patel, Ronak; Macklin, John J; Bargmann, Cornelia I; Ahrens, Misha B; Schreiter, Eric R; Jayaraman, Vivek; Looger, Loren L; Svoboda, Karel; Kim, Douglas S

    2016-01-01

    Genetically encoded calcium indicators (GECIs) allow measurement of activity in large populations of neurons and in small neuronal compartments, over times of milliseconds to months. Although GFP-based GECIs are widely used for in vivo neurophysiology, GECIs with red-shifted excitation and emission spectra have advantages for in vivo imaging because of reduced scattering and absorption in tissue, and a consequent reduction in phototoxicity. However, current red GECIs are inferior to the state-of-the-art GFP-based GCaMP6 indicators for detecting and quantifying neural activity. Here we present improved red GECIs based on mRuby (jRCaMP1a, b) and mApple (jRGECO1a), with sensitivity comparable to GCaMP6. We characterized the performance of the new red GECIs in cultured neurons and in mouse, Drosophila, zebrafish and C. elegans in vivo. Red GECIs facilitate deep-tissue imaging, dual-color imaging together with GFP-based reporters, and the use of optogenetics in combination with calcium imaging. PMID:27011354

  12. Active resonant subwavelength grating for scannerless range imaging sensors.

    SciTech Connect

    Kemme, Shanalyn A.; Nellums, Robert O.; Boye, Robert R.; Peters, David William

    2006-11-01

    In this late-start LDRD, we will present a design for a wavelength-agile, high-speed modulator that enables a long-term vision for the THz Scannerless Range Imaging (SRI) sensor. It takes the place of the currently-utilized SRI micro-channel plate which is limited to photocathode sensitive wavelengths (primarily in the visible and near-IR regimes). Two of Sandia's successful technologies--subwavelength diffractive optics and THz sources and detectors--are poised to extend the capabilities of the SRI sensor. The goal is to drastically broaden the SRI's sensing waveband--all the way to the THz regime--so the sensor can see through image-obscuring, scattering environments like smoke and dust. Surface properties, such as reflectivity, emissivity, and scattering roughness, vary greatly with the illuminating wavelength. Thus, objects that are difficult to image at the SRI sensor's present near-IR wavelengths may be imaged more easily at the considerably longer THz wavelengths (0.1 to 1mm). The proposed component is an active Resonant Subwavelength Grating (RSG). Sandia invested considerable effort on a passive RSG two years ago, which resulted in a highly-efficient (reflectivity greater than gold), wavelength-specific reflector. For this late-start LDRD proposal, we will transform the passive RSG design into an active laser-line reflector.

  13. Non-line-of-sight active imaging of scattered photons

    NASA Astrophysics Data System (ADS)

    Laurenzis, Martin; Velten, Andreas

    2013-10-01

    Laser Gated Viewing is a prominent sensing technology for optical imaging in harsh environments and can be applied to the vision through fog, smoke and other degraded environmental conditions as well as to the vision through sea water in submarine operation. A direct imaging of non-scattered photons (or ballistic photons) is limited in range and performance by the free optical path length i.e. the length in which a photon can propagate without interaction with scattering particles or object surfaces. The imaging and analysis of scattered photons can overcome these classical limitations and it is possible to realize a non-line-of-sight imaging. The spatial and temporal distribution of scattered photons can be analyzed by means of computational optics and their information of the scenario can be restored. In the case of Lambertian scattering sources the scattered photons carry information of the complete environment. Especial the information outside the line of sight or outside the visibility range is of high interest. Here, we discuss approaches for non line of sight active imaging with different indirect and direct illumination concepts (point, surface and volume scattering sources).

  14. Human brain activity with functional NIR optical imager

    NASA Astrophysics Data System (ADS)

    Luo, Qingming

    2001-08-01

    In this paper we reviewed the applications of functional near infrared optical imager in human brain activity. Optical imaging results of brain activity, including memory for new association, emotional thinking, mental arithmetic, pattern recognition ' where's Waldo?, occipital cortex in visual stimulation, and motor cortex in finger tapping, are demonstrated. It is shown that the NIR optical method opens up new fields of study of the human population, in adults under conditions of simulated or real stress that may have important effects upon functional performance. It makes practical and affordable for large populations the complex technology of measuring brain function. It is portable and low cost. In cognitive tasks subjects could report orally. The temporal resolution could be millisecond or less in theory. NIR method will have good prospects in exploring human brain secret.

  15. Mutation of FIG4 causes a rapidly progressive, asymmetric neuronal degeneration

    PubMed Central

    Zhang, Xuebao; Chow, Clement Y.; Sahenk, Zarife; Shy, Michael E.; Meisler, Miriam H.

    2008-01-01

    Recessive Charcot-Marie-Tooth disease type-4J (CMT4J) and its animal model, the pale tremor mouse (plt), are caused by mutations of the FIG4 gene encoding a PI(3,5)P2 5-phosphatase. We describe the 9-year clinical course of CMT4J, including asymmetric, rapidly progressive paralysis, in two siblings. Sensory symptoms were absent despite reduced numbers of sensory axons. Thus, the phenotypic presentation of CMT4J clinically resembles motor neuron disease. Time-lapse imaging of fibroblasts from CMT4J patients demonstrates impaired trafficking of intracellular organelles because of obstruction by vacuoles. Further characterization of plt mice identified axonal degeneration in motor and sensory neurons, limited segmental demyelination, lack of TUNEL staining and lack of accumulation of ubiquitinated protein in vacuoles of motor and sensory neurons. This study represents the first documentation of the natural history of CMT4J. Physical obstruction of organelle trafficking by vacuoles is a potential novel cellular mechanism of neurodegeneration. PMID:18556664

  16. Multiple LREK active contours for knee meniscus ultrasound image segmentation.

    PubMed

    Faisal, Amir; Ng, Siew-Cheok; Goh, Siew-Li; George, John; Supriyanto, Eko; Lai, Khin W

    2015-10-01

    Quantification of knee meniscus degeneration and displacement in an ultrasound image requires simultaneous segmentation of femoral condyle, meniscus, and tibial plateau in order to determine the area and the position of the meniscus. In this paper, we present an active contour for image segmentation that uses scalable local regional information on expandable kernel (LREK). It includes using a strategy to adapt the size of a local window in order to avoid being confined locally in a homogeneous region during the segmentation process. We also provide a multiple active contours framework called multiple LREK (MLREK) to deal with multiple object segmentation without merging and overlapping between the neighboring contours in the shared boundaries of separate regions. We compare its performance to other existing active contour models and show an improvement offered by our model. We then investigate the choice of various parameters in the proposed framework in response to the segmentation outcome. Dice coefficient and Hausdorff distance measures over a set of real knee meniscus ultrasound images indicate a potential application of MLREK for assessment of knee meniscus degeneration and displacement. PMID:25910057

  17. Characterisation of volatiles in dried white varieties figs (Ficus carica L.).

    PubMed

    Mujić, Ibrahim; Bavcon Kralj, Mojca; Jokić, Stela; Jug, Tjaša; Subarić, Drago; Vidović, Senka; Zivković, Jelena; Jarni, Kristjan

    2014-09-01

    The aromatic profile of volatiles in dried figs varieties Bružetka Bijela and Zimnica were characterised by headspace solid-phase (HS-SPME) procedure with gas chromatography-mass spectrometry analysis (GC-MS). The volatile compounds were distributed by distinct chemical classes, including alcohols, aldehydes, esters, terpenic compounds, and other compounds. The figs were dried in a pilot plant cabinet dryer. Prior to drying process, figs were pre-treated by sulphur dioxide, immersed in solution of citric acid and ascorbic acid, respectively. Several mathematical thin-layer drying models, available in the literature, were fitted to experimental data of figs, implementing non-linear regression analysis techniques. The results showed that pre-treatments of figs decrease significantly the drying time. The best thin-layer drying model in terms of fitting performance was Wang and Singh model. The major volatile compound in dried figs was benzaldehyde. After benzaldehyde, the most abundant aldehyde in dried figs was hexanal. The comparison among dried figs showed the highest abundance of aldehydes, in general, in non-treated (control) dried figs compared to pre-treated samples. Furthermore, ascorbic acid was the most efficient in preserving esters and alcohols in case of Bružetka Bijela, whereas in case of Zimnica, sulphur dioxide was in advance compared to ascorbic acid. Ethyl acetate was the most abundant ester found in dried figs. Among other compounds, 2-butanone,3-hydroxy was the most abundant identified volatiles. Linalool, as the only identified terpen, was in case of both dried fig varieties, preserved by immersion into ascorbic acid. The immersion into citric acid has not been so successful in volatiles conservation. PMID:25190838

  18. Direct imaging of macrophage activation during PDT treatment

    NASA Astrophysics Data System (ADS)

    Song, Sheng; Zhou, Feifan; Chen, Wei R.; Xing, Da

    2011-11-01

    Mounting evidence describes a more complex progress of macrophage activation during photodynamic therapy (PDT), which performing distinct immunological functions and different physiologies on surrounding cells and tissues. Macrophage-targeted PDT has been applied in the selective killing of cells involved in inflammation and tumor. We have previously shown that PDT-mediated tumor cells apoptosis can induce a higher level immune response than necrosis, and enhance the macrophage activation. However, the molecular mechanism of macrophage activation during PDT-induced apoptotic cells (AC) still unclear. Here, we use confocal microscopy to image the phagocytosis of tumor cells by macrophages. We also observed that PDT-treated AC can activate Toll-like receptors (TLRs) which are present on macrophages surface. Besides, the increase in nitric oxide (NO) formation in macrophages was detected in real time by a laser scanning microscopy. This study provided more details for understanding the molecular mechanism of the immune response induced by PDT-treated AC.

  19. Direct imaging of macrophage activation during PDT treatment

    NASA Astrophysics Data System (ADS)

    Song, Sheng; Zhou, Feifan; Chen, Wei R.; Xing, Da

    2012-03-01

    Mounting evidence describes a more complex progress of macrophage activation during photodynamic therapy (PDT), which performing distinct immunological functions and different physiologies on surrounding cells and tissues. Macrophage-targeted PDT has been applied in the selective killing of cells involved in inflammation and tumor. We have previously shown that PDT-mediated tumor cells apoptosis can induce a higher level immune response than necrosis, and enhance the macrophage activation. However, the molecular mechanism of macrophage activation during PDT-induced apoptotic cells (AC) still unclear. Here, we use confocal microscopy to image the phagocytosis of tumor cells by macrophages. We also observed that PDT-treated AC can activate Toll-like receptors (TLRs) which are present on macrophages surface. Besides, the increase in nitric oxide (NO) formation in macrophages was detected in real time by a laser scanning microscopy. This study provided more details for understanding the molecular mechanism of the immune response induced by PDT-treated AC.

  20. Study on Optimal Extracting Conditions and Anti-Cancer Effects of Fig Flavones

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As dietary components, flavones have health-promoting properties due to their high antioxidant capacity both in vivo and in vitro systems. Figs have been consumed as both herb medicine and popular fruit in daily life due to its polyphones, flavones and anthocyanins. However, fig residue from juice...

  1. Describing the appearance and flavor profiles of fresh fig (Ficus carica L.) cultivars.

    PubMed

    King, Ellena S; Hopfer, Helene; Haug, Megan T; Orsi, Jennifer D; Heymann, Hildegarde; Crisosto, Gayle M; Crisosto, Carlos H

    2012-12-01

    Twelve fig cultivars, including cultivars destined for the fresh and dried markets, were harvested from 6 locations and evaluated by a trained panel using descriptive sensory analysis. Instrumental measurements were taken at harvest and also during sensory analysis. Each fresh fig cultivar had a characteristic appearance and flavor sensory profile regardless of the source. The primary flavor attributes used to describe the fig cultivars were "fruity,"melon,"stone fruit,"berry,"citrus,"honey,"green," and "cucumber." Maturity levels significantly affected the chemical composition and sensory profiles of the fig cultivars. Less mature figs had a higher compression force, a thicker outer skin, and higher ratings for "green" and "latex" flavors, firmness, graininess, bitterness, tingling, and seed adhesiveness. Meanwhile, more mature figs had higher soluble solids concentration, and were perceptibly higher in "fruit" flavors, juiciness, stickiness, sliminess, and sweetness. The specific sensory terminology used for fig appearance and flavor profiles will assist with communication between marketers and consumers, which can increase fresh fig consumption. PMID:23170947

  2. Wine and vinegar-based attractants for the African fig fly (Diptera: Drosophilidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The African fig fly (AFF), Zaprionus indianus Gupta (Diptera: Drosophilidae), is an invasive fruit pest that has spread rapidly through much of the eastern United States after first being detected in Florida in 2005. This drosophilid is a primary pest of figs in Brazil, so there were initial concern...

  3. Host-Plant Species Conservatism and Ecology of a Parasitoid Fig Wasp Genus (Chalcidoidea; Sycoryctinae; Arachonia)

    PubMed Central

    McLeish, Michael J.; Beukman, Gary; van Noort, Simon; Wossler, Theresa C.

    2012-01-01

    Parasitoid diversity in terrestrial ecosystems is enormous. However, ecological processes underpinning their evolutionary diversification in association with other trophic groups are still unclear. Specialisation and interdependencies among chalcid wasps that reproduce on Ficus presents an opportunity to investigate the ecology of a multi-trophic system that includes parasitoids. Here we estimate the host-plant species specificity of a parasitoid fig wasp genus that attacks the galls of non-pollinating pteromalid and pollinating agaonid fig wasps. We discuss the interactions between parasitoids and the Ficus species present in a forest patch of Uganda in context with populations in Southern Africa. Haplotype networks are inferred to examine intraspecific mitochondrial DNA divergences and phylogenetic approaches used to infer putative species relationships. Taxonomic appraisal and putative species delimitation by molecular and morphological techniques are compared. Results demonstrate that a parasitoid fig wasp population is able to reproduce on at least four Ficus species present in a patch. This suggests that parasitoid fig wasps have relatively broad host-Ficus species ranges compared to fig wasps that oviposit internally. Parasitoid fig wasps did not recruit on all available host plants present in the forest census area and suggests an important ecological consequence in mitigating fitness trade-offs between pollinator and Ficus reproduction. The extent to which parasitoid fig wasps exert influence on the pollination mutualism must consider the fitness consequences imposed by the ability to interact with phenotypes of multiple Ficus and fig wasps species, but not equally across space and time. PMID:22970309

  4. Optical imaging of neural and hemodynamic brain activity

    NASA Astrophysics Data System (ADS)

    Schei, Jennifer Lynn

    Optical imaging technologies can be used to record neural and hemodynamic activity. Neural activity elicits physiological changes that alter the optical tissue properties. Specifically, changes in polarized light are concomitant with neural depolarization. We measured polarization changes from an isolated lobster nerve during action potential propagation using both reflected and transmitted light. In transmission mode, polarization changes were largest throughout the center of the nerve, suggesting that most of the optical signal arose from the inner nerve bundle. In reflection mode, polarization changes were largest near the edges, suggesting that most of the optical signal arose from the outer sheath. To overcome irregular cell orientation found in the brain, we measured polarization changes from a nerve tied in a knot. Our results show that neural activation produces polarization changes that can be imaged even without regular cell orientations. Neural activation expends energy resources and elicits metabolic delivery through blood vessel dilation, increasing blood flow and volume. We used spectroscopic imaging techniques combined with electrophysiological measurements to record evoked neural and hemodynamic responses from the auditory cortex of the rat. By using implantable optics, we measured responses across natural wake and sleep states, as well as responses following different amounts of sleep deprivation. During quiet sleep, evoked metabolic responses were larger compared to wake, perhaps because blood vessels were more compliant. When animals were sleep deprived, evoked hemodynamic responses were smaller following longer periods of deprivation. These results suggest that prolonged neural activity through sleep deprivation may diminish vascular compliance as indicated by the blunted vascular response. Subsequent sleep may allow vessels to relax, restoring their ability to deliver blood. These results also suggest that severe sleep deprivation or chronic

  5. Thermal Neutron Imaging in an Active Interrogation Environment

    SciTech Connect

    Vanier, Peter E.; Forman, Leon; Norman, Daren R.

    2009-03-10

    We have developed a thermal-neutron coded-aperture imager that reveals the locations of hydrogenous materials from which thermal neutrons are being emitted. This imaging detector can be combined with an accelerator to form an active interrogation system in which fast neutrons are produced in a heavy metal target by means of excitation by high energy photons. The photo-induced neutrons can be either prompt or delayed, depending on whether neutron-emitting fission products are generated. Provided that there are hydrogenous materials close to the target, some of the photo-induced neutrons slow down and emerge from the surface at thermal energies. These neutrons can be used to create images that show the location and shape of the thermalizing materials. Analysis of the temporal response of the neutron flux provides information about delayed neutrons from induced fission if there are fissionable materials in the target. The combination of imaging and time-of-flight discrimination helps to improve the signal-to-background ratio. It is also possible to interrogate the target with neutrons, for example using a D-T generator. In this case, an image can be obtained from hydrogenous material in a target without the presence of heavy metal. In addition, if fissionable material is present in the target, probing with fast neutrons can stimulate delayed neutrons from fission, and the imager can detect and locate the object of interest, using appropriate time gating. Operation of this sensitive detection equipment in the vicinity of an accelerator presents a number of challenges, because the accelerator emits electromagnetic interference as well as stray ionizing radiation, which can mask the signals of interest.

  6. Thermal neutron imaging in an active interrogation environment

    SciTech Connect

    Vanier,P.E.; Forman, L., and Norman, D.R.

    2009-03-10

    We have developed a thermal-neutron coded-aperture imager that reveals the locations of hydrogenous materials from which thermal neutrons are being emitted. This imaging detector can be combined with an accelerator to form an active interrogation system in which fast neutrons are produced in a heavy metal target by means of xcitation by high energy photons. The photo-induced neutrons can be either prompt or delayed, depending on whether neutronemitting fission products are generated. Provided that there are hydrogenous materials close to the target, some of the photo-induced neutrons slow down and emerge from the surface at thermal energies. These neutrons can be used to create images that show the location and shape of the thermalizing materials. Analysis of the temporal response of the neutron flux provides information about delayed neutrons from induced fission if there are fissionable materials in the target. The combination of imaging and time-of-flight discrimination helps to improve the signal-to-background ratio. It is also possible to interrogate the target with neutrons, for example using a D-T generator. In this case, an image can be obtained from hydrogenous material in a target without the presence of heavy metal. In addition, if fissionable material is present in the target, probing with fast neutrons can stimulate delayed neutrons from fission, and the imager can detect and locate the object of interest, using appropriate time gating. Operation of this sensitive detection equipment in the vicinity of an accelerator presents a number of challenges, because the accelerator emits electromagnetic interference as well as stray ionizing radiation, which can mask the signals of interest.

  7. Bioluminescence imaging of estrogen receptor activity during breast cancer progression

    PubMed Central

    Vantaggiato, Cristina; Dell’Omo, Giulia; Ramachandran, Balaji; Manni, Isabella; Radaelli, Enrico; Scanziani, Eugenio; Piaggio, Giulia; Maggi, Adriana; Ciana, Paolo

    2016-01-01

    Estrogen receptors (ER) are known to play an important regulatory role in mammary gland development as well as in its neoplastic transformation. Although several studies highlighted the contribution of ER signaling in the breast transformation, little is known about the dynamics of ER state of activity during carcinogenesis due to the lack of appropriate models for measuring the extent of receptor signaling in time, in the same animal. To this aim, we have developed a reporter mouse model for the non-invasive in vivo imaging of ER activity: the ERE-Luc reporter mouse. ERE-Luc is a transgenic mouse generated with a firefly luciferase (Luc) reporter gene driven by a minimal promoter containing an estrogen responsive element (ERE). This model allows to measure receptor signaling in longitudinal studies by bioluminescence imaging (BLI). Here, we have induced sporadic mammary cancers by treating systemically ERE-Luc reporter mice with DMBA (9,10-dimethyl 1,2-benzanthracene) and measured receptor signaling by in vivo imaging in individual animals from early stage until a clinically palpable tumor appeared in the mouse breast. We showed that DMBA administration induces an increase of bioluminescence in the whole abdominal area 6 h after treatment, the signal rapidly disappears. Several weeks later, strong bioluminescence is observed in the area corresponding to the mammary glands. In vivo and ex vivo imaging analysis demonstrated that this bioluminescent signal is localized in the breast area undergoing neoplastic transformation. We conclude that this non-invasive assay is a novel relevant tool to identify the activation of the ER signaling prior the morphological detection of the neoplastic transformation. PMID:27069764

  8. Bioluminescence imaging of estrogen receptor activity during breast cancer progression.

    PubMed

    Vantaggiato, Cristina; Dell'Omo, Giulia; Ramachandran, Balaji; Manni, Isabella; Radaelli, Enrico; Scanziani, Eugenio; Piaggio, Giulia; Maggi, Adriana; Ciana, Paolo

    2016-01-01

    Estrogen receptors (ER) are known to play an important regulatory role in mammary gland development as well as in its neoplastic transformation. Although several studies highlighted the contribution of ER signaling in the breast transformation, little is known about the dynamics of ER state of activity during carcinogenesis due to the lack of appropriate models for measuring the extent of receptor signaling in time, in the same animal. To this aim, we have developed a reporter mouse model for the non-invasive in vivo imaging of ER activity: the ERE-Luc reporter mouse. ERE-Luc is a transgenic mouse generated with a firefly luciferase (Luc) reporter gene driven by a minimal promoter containing an estrogen responsive element (ERE). This model allows to measure receptor signaling in longitudinal studies by bioluminescence imaging (BLI). Here, we have induced sporadic mammary cancers by treating systemically ERE-Luc reporter mice with DMBA (9,10-dimethyl 1,2-benzanthracene) and measured receptor signaling by in vivo imaging in individual animals from early stage until a clinically palpable tumor appeared in the mouse breast. We showed that DMBA administration induces an increase of bioluminescence in the whole abdominal area 6 h after treatment, the signal rapidly disappears. Several weeks later, strong bioluminescence is observed in the area corresponding to the mammary glands. In vivo and ex vivo imaging analysis demonstrated that this bioluminescent signal is localized in the breast area undergoing neoplastic transformation. We conclude that this non-invasive assay is a novel relevant tool to identify the activation of the ER signaling prior the morphological detection of the neoplastic transformation. PMID:27069764

  9. Imaging Odor-Evoked Activities in the Mouse Olfactory Bulb using Optical Reflectance and Autofluorescence Signals

    PubMed Central

    Chery, Romain; L'Heureux, Barbara; Bendahmane, Mounir; Renaud, Rémi; Martin, Claire; Pain, Frédéric; Gurden, Hirac

    2011-01-01

    allows efficient detection and identification of chemical substances in the environment (food, predators). The OB is the first relay of olfactory information processing in the brain. It receives afferent projections from the olfactory primary sensory neurons that detect volatile odorant molecules. Each sensory neuron expresses only one type of odorant receptor and neurons carrying the same type of receptor send their nerve processes to the same well-defined microregions of ˜100μm3 constituted of discrete neuropil, the olfactory glomerulus (Fig. 1). In the last decade, IOS imaging has fostered the functional exploration of the OB5, 6, 7 which has become one of the most studied sensory structures. The mapping of OB activity with FAS imaging has not been performed yet. Here, we show the successive steps of an efficient protocol for IOS and FAS imaging to map odor-evoked activities in the mouse OB. PMID:22064685

  10. Preliminary investigations of active pixel sensors in Nuclear Medicine imaging

    NASA Astrophysics Data System (ADS)

    Ott, Robert; Evans, Noel; Evans, Phil; Osmond, J.; Clark, A.; Turchetta, R.

    2009-06-01

    Three CMOS active pixel sensors have been investigated for their application to Nuclear Medicine imaging. Startracker with 525×525 25 μm square pixels has been coupled via a fibre optic stud to a 2 mm thick segmented CsI(Tl) crystal. Imaging tests were performed using 99mTc sources, which emit 140 keV gamma rays. The system was interfaced to a PC via FPGA-based DAQ and optical link enabling imaging rates of 10 f/s. System noise was measured to be >100e and it was shown that the majority of this noise was fixed pattern in nature. The intrinsic spatial resolution was measured to be ˜80 μm and the system spatial resolution measured with a slit was ˜450 μm. The second sensor, On Pixel Intelligent CMOS (OPIC), had 64×72 40 μm pixels and was used to evaluate noise characteristics and to develop a method of differentiation between fixed pattern and statistical noise. The third sensor, Vanilla, had 520×520 25 μm pixels and a measured system noise of ˜25e. This sensor was coupled directly to the segmented phosphor. Imaging results show that even at this lower level of noise the signal from 140 keV gamma rays is small as the light from the phosphor is spread over a large number of pixels. Suggestions for the 'ideal' sensor are made.

  11. Active contours for localizing polyps in colonoscopic NBI image data

    NASA Astrophysics Data System (ADS)

    Breier, Matthias; Gross, Sebastian; Behrens, Alexander; Stehle, Thomas; Aach, Til

    2011-03-01

    Colon cancer is the third most common type of cancer in the United States of America. Every year about 140,000 people are newly diagnosed with colon cancer. Early detection is crucial for a successful therapy. The standard screening procedure is called colonoscopy. Using this endoscopic examination physicians can find colon polyps and remove them if necessary. Adenomatous colon polyps are deemed a preliminary stage of colon cancer. The removal of a polyp, though, can lead to complications like severe bleedings or colon perforation. Thus, only polyps diagnosed as adenomatous should be removed. To decide whether a polyp is adenomatous the polyp's surface structure including vascular patterns has to be inspected. Narrow-Band imaging (NBI) is a new tool to improve visibility of vascular patterns of the polyps. The first step for an automatic polyp classification system is the localization of the polyp. We investigate active contours for the localization of colon polyps in NBI image data. The shape of polyps, though roughly approximated by an elliptic form, is highly variable. Active contours offer the flexibility to adapt to polyp variation well. To avoid clustering of contour polygon points we propose the application of active rays. The quality of the results was evaluated based on manually segmented polyps as ground truth data. The results were compared to a template matching approach and to the Generalized Hough Transform. Active contours are superior to the Hough transform and perform equally well as the template matching approach.

  12. Neutron coincidence imaging for active and passive neutron assays

    SciTech Connect

    Estep, R. J.; Brunson, G. S.; Melton, S. G.

    2001-01-01

    Neutron multiplicity assay algorithms for {sup 240}Pu assume a point source of fission neutrons that are detected in a single detector channel. The {sup 240}Pu in real waste, however, is more likely to be distributed throughout the container in some random way. For different reasons, this leads to significant errors when using either multiplicity or simpler coincidence analyses. Reduction of these errors can be achieved using tomographic imaging. In this talk we report on our results from using neutron singles and coincidence data between tagged detector pairs to provide enhanced tomographic imaging capabilities to a crate nondestructive assay system. Only simulated passive coincidence data is examined here, although the higher signal rates from active coincidence counting hold more promise for waste management. The active coincidence approach has significantly better sensitivity than the passive and is not significantly perturbed by (alpha,n) contributions. Our study was based primarily on simulated neutron pulse trains derived from the Los Alamos SIM3D software, which were subjected to analysis using the Los Alamos CTEN-FIT and TGS-FIT software. We found significantly improved imaging capability using the coincidence and singles rate data than could be obtained using the singles rate alone.

  13. Quantitative phase imaging technologies to assess neuronal activity (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Thouvenin, Olivier; Fink, Mathias; Boccara, Claude

    2016-03-01

    Active neurons tends to have a different dynamical behavior compared to resting ones. Non-exhaustively, vesicular transport towards the synapses is increased, since axonal growth becomes slower. Previous studies also reported small phase variations occurring simultaneously with the action potential. Such changes exhibit times scales ranging from milliseconds to several seconds on spatial scales smaller than the optical diffraction limit. Therefore, QPI systems are of particular interest to measure neuronal activity without labels. Here, we report the development of two new QPI systems that should enable the detection of such activity. Both systems can acquire full field phase images with a sub nanometer sensitivity at a few hundreds of frames per second. The first setup is a synchronous combination of Full Field Optical Coherence Tomography (FF-OCT) and Fluorescence wide field imaging. The latter modality enables the measurement of neurons electrical activity using calcium indicators. In cultures, FF-OCT exhibits similar features to Digital Holographic Microscopy (DHM), except from complex computational reconstruction. However, FF-OCT is of particular interest in order to measure phase variations in tissues. The second setup is based on a Quantitative Differential Interference Contrast setup mounted in an epi-illumination configuration with a spectrally incoherent illumination. Such a common path interferometer exhibits a very good mechanical stability, and thus enables the measurement of phase images during hours. Additionally, such setup can not only measure a height change, but also an optical index change for both polarization. Hence, one can measure simultaneously a phase change and a birefringence change.

  14. Active contour based segmentation of resected livers in CT images

    NASA Astrophysics Data System (ADS)

    Oelmann, Simon; Oyarzun Laura, Cristina; Drechsler, Klaus; Wesarg, Stefan

    2015-03-01

    The majority of state of the art segmentation algorithms are able to give proper results in healthy organs but not in pathological ones. However, many clinical applications require an accurate segmentation of pathological organs. The determination of the target boundaries for radiotherapy or liver volumetry calculations are examples of this. Volumetry measurements are of special interest after tumor resection for follow up of liver regrow. The segmentation of resected livers presents additional challenges that were not addressed by state of the art algorithms. This paper presents a snakes based algorithm specially developed for the segmentation of resected livers. The algorithm is enhanced with a novel dynamic smoothing technique that allows the active contour to propagate with different speeds depending on the intensities visible in its neighborhood. The algorithm is evaluated in 6 clinical CT images as well as 18 artificial datasets generated from additional clinical CT images.

  15. High-throughput imaging of neuronal activity in Caenorhabditis elegans

    PubMed Central

    Larsch, Johannes; Ventimiglia, Donovan; Bargmann, Cornelia I.; Albrecht, Dirk R.

    2013-01-01

    Neuronal responses to sensory inputs can vary based on genotype, development, experience, or stochastic factors. Existing neuronal recording techniques examine a single animal at a time, limiting understanding of the variability and range of potential responses. To scale up neuronal recordings, we here describe a system for simultaneous wide-field imaging of neuronal calcium activity from at least 20 Caenorhabditis elegans animals under precise microfluidic chemical stimulation. This increased experimental throughput was used to perform a systematic characterization of chemosensory neuron responses to multiple odors, odor concentrations, and temporal patterns, as well as responses to pharmacological manipulation. The system allowed recordings from sensory neurons and interneurons in freely moving animals, whose neuronal responses could be correlated with behavior. Wide-field imaging provides a tool for comprehensive circuit analysis with elevated throughput in C. elegans. PMID:24145415

  16. Superresolution Imaging of Amyloid Fibrils with Binding-Activated Probes

    PubMed Central

    2013-01-01

    Protein misfolding into amyloid-like aggregates underlies many neurodegenerative diseases. Thus, insights into the structure and function of these amyloids will provide valuable information on the pathological mechanisms involved and aid in the design of improved drugs for treating amyloid-based disorders. However, determining the structure of endogenous amyloids at high resolution has been difficult. Here we employ binding-activated localization microscopy (BALM) to acquire superresolution images of α-synuclein amyloid fibrils with unprecedented optical resolution. We propose that BALM imaging can be extended to study the structure of other amyloids, for differential diagnosis of amyloid-related diseases and for discovery of drugs that perturb amyloid structure for therapy. PMID:23594172

  17. Active Volcano Monitoring using a Space-based Hyperspectral Imager

    NASA Astrophysics Data System (ADS)

    Cipar, J. J.; Dunn, R.; Cooley, T.

    2010-12-01

    Active volcanoes occur on every continent, often in close proximity to heavily populated areas. While ground-based studies are essential for scientific research and disaster mitigation, remote sensing from space can provide rapid and continuous monitoring of active and potentially active volcanoes [Ramsey and Flynn, 2004]. In this paper, we report on hyperspectral measurements of Kilauea volcano, Hawaii. Hyperspectral images obtained by the US Air Force TacSat-3/ARTEMIS sensor [Lockwood et al, 2006] are used to obtain estimates of the surface temperatures for the volcano. ARTEMIS measures surface-reflected light in the visible, near-infrared, and short-wave infrared bands (VNIR-SWIR). The SWIR bands are known to be sensitive to thermal radiation [Green, 1996]. For example, images from the NASA Hyperion hyperspectral sensor have shown the extent of wildfires and active volcanoes [Young, 2009]. We employ the methodology described by Dennison et al, (2006) to obtain an estimate of the temperature of the active region of Kilauea. Both day and night-time images were used in the analysis. To improve the estimate, we aggregated neighboring pixels. The active rim of the lava lake is clearly discernable in the temperature image, with a measured temperature exceeding 1100o C. The temperature decreases markedly on the exterior of the summit crater. While a long-wave infrared (LWIR) sensor would be ideal for volcano monitoring, we have shown that the thermal state of an active volcano can be monitored using the SWIR channels of a reflective hyperspectral imager. References: Dennison, Philip E., Kraivut Charoensiri, Dar A. Roberts, Seth H. Peterson, and Robert O. Green (2006). Wildfire temperature and land cover modeling using hyperspectral data, Remote Sens. Environ., vol. 100, pp. 212-222. Green, R. O. (1996). Estimation of biomass fire temperature and areal extent from calibrated AVIRIS spectra, in Summaries of the 6th Annual JPL Airborne Earth Science Workshop, Pasadena, CA

  18. The non-pollinating fig wasps associated with Ficus guianensis: Community structure and impact of the large species on the fig/pollinator mutualism

    NASA Astrophysics Data System (ADS)

    Conchou, Lucie; Ciminera, Marina; Hossaert-McKey, Martine; Kjellberg, Finn

    2014-05-01

    Understanding the ecology of non-pollinating fig-wasp communities depends on a good knowledge of larval feeding habits of the species involved, which can be gall inducers, kleptoparasites, parasitoids or seed eaters. However, larval feeding habits are poorly known and most community ecology studies on NPFW are based on hypothetical feeding habits or data analyzed independently of feeding habit. Here we take advantage of the particular situation in Ficus guianensis whose community is dominated by large NPFW, i.e. species that are obviously larger than pollinators, to establish the community structure and feeding habits of the most frequent wasps. We provide the first non-ambiguous negative correlation between the number of NPFW and the production of pollinators and seeds. Each developing large NPFW represents a disproportionate cost to the mutualism as it is responsible for the loss of about ten seeds plus pollinators, i.e. about 10% of the production of a fig.

  19. Water availability determines the richness and density of fig trees within Brazilian semideciduous forest landscapes

    NASA Astrophysics Data System (ADS)

    Coelho, Luís Francisco Mello; Ribeiro, Milton Cezar; Pereira, Rodrigo Augusto Santinelo

    2014-05-01

    The success of fig trees in tropical ecosystems is evidenced by the great diversity (+750 species) and wide geographic distribution of the genus. We assessed the contribution of environmental variables on the species richness and density of fig trees in fragments of seasonal semideciduous forest (SSF) in Brazil. We assessed 20 forest fragments in three regions in Sao Paulo State, Brazil. Fig tree richness and density was estimated in rectangular plots, comprising 31.4 ha sampled. Both richness and fig tree density were linearly modeled as function of variables representing (1) fragment metrics, (2) forest structure, and (3) landscape metrics expressing water drainage in the fragments. Model selection was performed by comparing the AIC values (Akaike Information Criterion) and the relative weight of each model (wAIC). Both species richness and fig tree density were better explained by the water availability in the fragment (meter of streams/ha): wAICrichness = 0.45, wAICdensity = 0.96. The remaining variables related to anthropic perturbation and forest structure were of little weight in the models. The rainfall seasonality in SSF seems to select for both establishment strategies and morphological adaptations in the hemiepiphytic fig tree species. In the studied SSF, hemiepiphytes established at lower heights in their host trees than reported for fig trees in evergreen rainforests. Some hemiepiphytic fig species evolved superficial roots extending up to 100 m from their trunks, resulting in hectare-scale root zones that allow them to efficiently forage water and soil nutrients. The community of fig trees was robust to variation in forest structure and conservation level of SSF fragments, making this group of plants an important element for the functioning of seasonal tropical forests.

  20. Competitive Exclusion among Fig Wasps Achieved via Entrainment of Host Plant Flowering Phenology

    PubMed Central

    Chen, Yan; Zhang, Jian; Compton, Stephen G.; Chen, Xiao-Yong

    2014-01-01

    Molecular techniques are revealing increasing numbers of morphologically similar but co-existing cryptic species, challenging the niche theory. To understand the co-existence mechanism, we studied phenologies of morphologically similar species of fig wasps that pollinate the creeping fig (F. pumila) in eastern China. We compared phenologies of fig wasp emergence and host flowering at sites where one or both pollinators were present. At the site where both pollinators were present, we used sticky traps to capture the emerged fig wasps and identified species identity using mitochondrial DNA COI gene. We also genotyped F. pumila individuals of the three sites using polymorphic microsatellites to detect whether the host populations were differentiated. Male F. pumila produced two major crops annually, with figs receptive in spring and summer. A small partial third crop of receptive figs occurred in the autumn, but few of the second crop figs matured at that time. Hence, few pollinators were available to enter third crop figs and they mostly aborted, resulting in two generations of pollinating wasps each year, plus a partial third generation. Receptive figs were produced on male plants in spring and summer, timed to coincide with the release of short-lived adult pollinators from the same individual plants. Most plants were pollinated by a single species. Plants pollinated by Wiebesia sp. 1 released wasps earlier than those pollinated by Wiebesia sp. 3, with little overlap. Plants occupied by different pollinators were not spatially separated, nor genetically distinct. Our findings show that these differences created mismatches with the flight periods of the other Wiebesia species, largely ‘reserving’ individual plants for the resident pollinator species. This pre-emptive competitive displacement may prevent long term co-existence of the two pollinators. PMID:24849458

  1. Obligate mutualism within a host drives the extreme specialization of a fig wasp genome

    PubMed Central

    2013-01-01

    Background Fig pollinating wasps form obligate symbioses with their fig hosts. This mutualism arose approximately 75 million years ago. Unlike many other intimate symbioses, which involve vertical transmission of symbionts to host offspring, female fig wasps fly great distances to transfer horizontally between hosts. In contrast, male wasps are wingless and cannot disperse. Symbionts that keep intimate contact with their hosts often show genome reduction, but it is not clear if the wide dispersal of female fig wasps will counteract this general tendency. We sequenced the genome of the fig wasp Ceratosolen solmsi to address this question. Results The genome size of the fig wasp C. solmsi is typical of insects, but has undergone dramatic reductions of gene families involved in environmental sensing and detoxification. The streamlined chemosensory ability reflects the overwhelming importance of females finding trees of their only host species, Ficus hispida, during their fleeting adult lives. Despite long-distance dispersal, little need exists for detoxification or environmental protection because fig wasps spend nearly all of their lives inside a largely benign host. Analyses of transcriptomes in females and males at four key life stages reveal that the extreme anatomical sexual dimorphism of fig wasps may result from a strong bias in sex-differential gene expression. Conclusions Our comparison of the C. solmsi genome with other insects provides new insights into the evolution of obligate mutualism. The draft genome of the fig wasp, and transcriptomic comparisons between both sexes at four different life stages, provide insights into the molecular basis for the extreme anatomical sexual dimorphism of this species. PMID:24359812

  2. Calcium imaging of infrared-stimulated activity in rodent brain.

    PubMed

    Cayce, Jonathan Matthew; Bouchard, Matthew B; Chernov, Mykyta M; Chen, Brenda R; Grosberg, Lauren E; Jansen, E Duco; Hillman, Elizabeth M C; Mahadevan-Jansen, Anita

    2014-04-01

    Infrared neural stimulation (INS) is a promising neurostimulation technique that can activate neural tissue with high spatial precision and without the need for exogenous agents. However, little is understood about how infrared light interacts with neural tissue on a cellular level, particularly within the living brain. In this study, we use calcium sensitive dye imaging on macroscopic and microscopic scales to explore the spatiotemporal effects of INS on cortical calcium dynamics. The INS-evoked calcium signal that was observed exhibited a fast and slow component suggesting activation of multiple cellular mechanisms. The slow component of the evoked signal exhibited wave-like properties suggesting network activation, and was verified to originate from astrocytes through pharmacology and 2-photon imaging. We also provide evidence that the fast calcium signal may have been evoked through modulation of glutamate transients. This study demonstrates that pulsed infrared light can induce intracellular calcium modulations in both astrocytes and neurons, providing new insights into the mechanisms of action of INS in the brain. PMID:24674600

  3. Calcium imaging of infrared-stimulated activity in rodent brain

    PubMed Central

    Cayce, Jonathan Matthew; Bouchard, Matthew B.; Chernov, Mykyta M.; Chen, Brenda R.; Grosberg, Lauren E.; Jansen, E. Duco; Hillman, Elizabeth M. C.; Mahadevan-Jansen, Anita

    2014-01-01

    Summary Infrared neural stimulation (INS) is a promising neurostimulation technique that can activate neural tissue with high spatial precision and without the need for exogenous agents. However, little is understood about how infrared light interacts with neural tissue on a cellular level, particularly within the living brain. In this study, we use calcium sensitive dye imaging on macroscopic and microscopic scales to explore the spatiotemporal effects of INS on cortical calcium dynamics. The INS-evoked calcium signal that was observed exhibited a fast and slow component suggesting activation of multiple cellular mechanisms. The slow component of the evoked signal exhibited wave-like properties suggesting network activation, and was verified to originate from astrocytes through pharmacology and 2-photon imaging. We also provide evidence that the fast calcium signal may have been evoked through modulation of glutamate transients. This study demonstrates that pulsed infrared light can induce intracellular calcium modulations in both astrocytes and neurons, providing new insights into the mechanisms of action of INS in the brain. PMID:24674600

  4. Evaluation of antioxidant activity, sugar composition, and flow packaging potential for california dried and fresh figs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Potential sensory perception and antioxidant capacity varied among these 20 cultivars tested that included dry and fresh traditional and recently introduced potentially dry or fresh varieties. Fructose, sweetness power and total phenolics levels were similar between the new introductions varieties a...

  5. Biosorption of Ni(II) by Fig Male: Optimization and Modeling Using a Full Factorial Design.

    PubMed

    Madjene, F; Chergui, A; Trari, M

    2016-06-01

    The fig male (FM) is successfully used as biosorbent for Ni(2+) removal. The maximum removal efficiency (96.6%) is obtained at pH ~ 5 for a concentration of 1.70 mmol L(-1) and catalyst dose of 5 g L(-1) in less than 10 minutes. The Ni(2+) uptake follows a pseudo-second-order kinetic, the rate constants increase with increasing temperature, and an activation energy of 55.48 kJ mol(-1) is found. The thermodynamic parameters indicate a spontaneous endothermic bisorption. The isotherm data are fitted by the Langmuir and Dubinin-Radushkevich models. The former indicates a maximum Ni(2+) uptake of 0.459 mmol g(-1), which is higher than that of most biosorbents investigated to date. The FTIR spectra reveal the biosorption mechanism between Ni(2+) and FM functional groups. An empirical modeling is performed by using a 2(3) full factorial design, and a regression equation for Ni(2+) biosorption is determined. The biosorbent mass and pH are the most significant parameters affecting the Ni(2+) biosorption. PMID:27225783

  6. An active seismic experiment at Tenerife Island (Canary Island, Spain): Imaging an active volcano edifice

    NASA Astrophysics Data System (ADS)

    Garcia-Yeguas, A.; Ibañez, J. M.; Rietbrock, A.; Tom-Teidevs, G.

    2008-12-01

    An active seismic experiment to study the internal structure of Teide Volcano was carried out on Tenerife, a volcanic island in Spain's Canary Islands. The main objective of the TOM-TEIDEVS experiment is to obtain a 3-dimensional structural image of Teide Volcano using seismic tomography and seismic reflection/refraction imaging techniques. At present, knowledge of the deeper structure of Teide and Tenerife is very limited, with proposed structural models mainly based on sparse geophysical and geological data. This multinational experiment which involves institutes from Spain, Italy, the United Kingdom, Ireland, and Mexico will generate a unique high resolution structural image of the active volcano edifice and will further our understanding of volcanic processes.

  7. Effect of contraceptive steroids on monoamine oxidase activity

    PubMed Central

    Southgate, Jennifer; Collins, G. G. S.; Pryse-Davies, J.; Sandler, M.

    1969-01-01

    Cyclical variations in monoamine oxidase activity during the human menstrual cycle, specific to the endometrium and modified in women undergoing contraceptive steroid treatment, may reflect changes in hormonal environment. Treatment of rats with individual constituents of the contraceptive pill causes analogous changes: oestrogens inhibit and progestogens potentiate uterine monoamine oxidase activity. ImagesFig. 2Fig. 3

  8. Multiresolution active contour model applied on lung and colon images

    NASA Astrophysics Data System (ADS)

    Dehmeshki, Jamshid; Siddique, Musib; Wong, Wing; Chis Ster, Irina

    2004-05-01

    This paper deploys a wavelet based scale-space approach to extract the boundary of the object of interest in medical CT images. The classical approach of the active contour models consists of starting with an initial contour, to deform it under the action of some forces attracting the contour towards the edges by means of a set of forces. The mathematical model involves in the minimisation of an objective function called energy functional, which depends on the geometry of the contour as well as of the image characteristics. Various strategies could be used for the formulation of the energy functional and its optimisation. In this study, a wavelet based scale-space approach has been adopted. The coarsest scale is able to enlarge the capture region surrounding an object and avoids the trapping of contour into weak edges. The finer scales are used to refine the contour as close as possible to the boundary of the object. An adaptive scale coefficient for the balloon energy has been introduced. Four levels of resolution have been applied in order to get reproducibility of the contour despite poor different initialisations. The scheme has been applied to segment the regions of interest in CT lung and colon images. The result has been shown to be accurate and reproducible for the cases containing fat, holes and other small high intensity objects inside lung nodules as well as colon polyps.

  9. THERMAL IMAGING OF ACTIVE MAGNETIC REGERNERATOR MCE MATERIALS DURING OPERATION

    SciTech Connect

    Shassere, Benjamin; West, David L; Abdelaziz, Omar; Evans III, Boyd Mccutchen

    2012-01-01

    An active magnetic regenerator (AMR) prototype was constructed that incorporates a Gd sheet into the regenerator wall to enable visualization of the system s thermal transients. In this experiment, the thermal conditions inside the AMR are observed under a variety of operating conditions. An infrared (IR) camera is employed to visualize the thermal transients within the AMR. The IR camera is used to visually and quantitatively evaluate the temperature difference and thus giving means to calculate the performance of the system under the various operating conditions. Thermal imaging results are presented for two differing experimental test runs. Real time imaging of the thermal state of the AMR has been conducted while operating the system over a range of conditions. A 1 Tesla twin-coil electromagnet (situated on a C frame base) is used for this experiment such that all components are stationary during testing. A modular, linear reciprocating system has been realized in which the effects of regenerator porosity and utilization factor can be investigated. To evaluate the performance variation in porosity and utilization factor the AMR housing was constructed such that the plate spacing of the Gd sheets may be varied. Each Gd sheet has dimensions of 38 mm wide and 66 mm long with a thickness of 1 mm and the regenerator can hold a maximum of 29 plates with a spacing of 0.25 mm. Quantitative and thermal imaging results are presented for several regenerator configurations.

  10. Fusion of FIG to the receptor tyrosine kinase ROS in a glioblastoma with an interstitial del(6)(q21q21).

    PubMed

    Charest, Alain; Lane, Keara; McMahon, Kevin; Park, Julie; Preisinger, Elizabeth; Conroy, Helen; Housman, David

    2003-05-01

    The transmembrane proto-oncogene receptor tyrosine kinase (RTK) ROS is an orphan receptor that is aberrantly expressed in neoplasms of the central nervous system. Here, we report the fusion of its carboxy-terminal kinase domain to the amino-terminal portion of a protein called FIG (Fused in Glioblastoma) in a human glioblastoma multiforme (GBM). By characterizing both FIG and ROS genes in normal and in U118MG GBM cells, we determined that an intra-chromosomal homozygous deletion of 240 kilobases on 6q21 is responsible for the formation of the FIG-ROS locus. The FIG-ROS transcript is encoded by 7 FIG exons and 9 ROS-derived exons. We also demonstrate that the FIG-ROS locus encodes for an in-frame fusion protein with a constitutively active kinase activity, suggesting that FIG-ROS may act as an oncogene. This is the first example of a fusion RTK protein that results from an intra-chromosomal deletion, and it represents the first fusion RTK protein isolated from a human astrocytoma. PMID:12661006

  11. MCT SWIR modules for passive and active imaging applications

    NASA Astrophysics Data System (ADS)

    Breiter, R.; Benecke, M.; Eich, D.; Figgemeier, H.; Weber, A.; Wendler, J.; Sieck, A.

    2016-05-01

    Based on AIM's state-of-the-art MCT IR technology, detector modules for the SWIR spectral range have been developed, fabricated and characterized. While LPE grown MCT FPAs with extended 2.5μm cut-off have been fabricated and integrated also MBE grown MCT on GaAs is considered for future production. Two imaging applications have been in focus operating either in passive mode by making use of e.g. the night glow, or in active mode by laser illumination for gated viewing. Dedicated readout integrated circuits (ROIC), realized in 0.18μm Si-CMOS technology providing the required functionality for passive imaging and gated imaging, have been designed and implemented. For both designs a 640x512 15μm pitch format was chosen. The FPAs are integrated in compact dewar cooler configurations using AIM's split linear coolers. A command and control electronics (CCE) provides supply voltages, biasing, clocks, control and video digitization for easy system interfacing. For imaging under low-light conditions a low-noise 640x512 15μm pitch ROIC with CTIA input stages and correlated double sampling was designed. The ROIC provides rolling shutter and snapshot integration. To reduce size, weight, power and cost (SWaP-C) a 640x512 format detector in a 10μm pitch is under development. The module makes use of the extended SWIR spectral cut-off up to 2.5μm. To be used for active gated-viewing operation SWIR MCT avalanche photodiodes have been implemented and characterized on FPA level in a 640x512 15μm pitch format. The specific ROIC provides also the necessary functions for range gate control and triggering by the laser illumination. First lab and field tests of a gated viewing demonstrator have been carried out. The paper will present the development status and performance results of AIM's MCT based SWIR Modules for imaging applications.

  12. Active constraint control for image-guided robotic surgery.

    PubMed

    Yen, P-L; Davies, B L

    2010-01-01

    The concept of active constraint control for image-guided robotic surgery is introduced, together with its benefits and a short outline of its history. The clinical use of active constraint control in orthopaedic surgery is discussed, together with the outcomes of a clinical trial for unicondylar knee replacement surgery. The evolution of the robotic design from large costly structures towards simpler, more cost-effective systems is also presented, leading to the design of the Acrobot 'Sculptor' system. A new approach to the achievement of robotic total knee replacement is also presented, in which a high-speed rotary cutter is used to slice through the bone to achieve a speedy resection. The control concept is presented, together with the results of trials on animal bones and a cadaver, showing that it is possible to remove large quantities of bone both quickly and accurately. PMID:20718267

  13. Imaging Active Surface Processes in Barnacle Adhesive Interfaces.

    PubMed

    Golden, Joel P; Burden, Daniel K; Fears, Kenan P; Barlow, Daniel E; So, Christopher R; Burns, Justin; Miltenberg, Benjamin; Orihuela, Beatriz; Rittshof, Daniel; Spillmann, Christopher M; Wahl, Kathryn J; Tender, Leonard M

    2016-01-19

    Surface plasmon resonance imaging (SPRI) and voltammetry were used simultaneously to monitor Amphibalanus (=Balanus) amphitrite barnacles reattached and grown on gold-coated glass slides in artificial seawater. Upon reattachment, SPRI revealed rapid surface adsorption of material with a higher refractive index than seawater at the barnacle/gold interface. Over longer time periods, SPRI also revealed secretory activity around the perimeter of the barnacle along the seawater/gold interface extending many millimeters beyond the barnacle and varying in shape and region with time. Ex situ experiments using attenuated total reflectance infrared (ATR-IR) spectroscopy confirmed that reattachment of barnacles was accompanied by adsorption of protein to surfaces on similar time scales as those in the SPRI experiments. Barnacles were grown through multiple molting cycles. While the initial reattachment region remained largely unchanged, SPRI revealed the formation of sets of paired concentric rings having alternately darker/lighter appearance (corresponding to lower and higher refractive indices, respectively) at the barnacle/gold interface beneath the region of new growth. Ex situ experiments coupling the SPRI imaging with optical and FTIR microscopy revealed that the paired rings coincide with molt cycles, with the brighter rings associated with regions enriched in amide moieties. The brighter rings were located just beyond orifices of cement ducts, consistent with delivery of amide-rich chemistry from the ducts. The darker rings were associated with newly expanded cuticle. In situ voltammetry using the SPRI gold substrate as the working electrode revealed presence of redox active compounds (oxidation potential approx 0.2 V vs Ag/AgCl) after barnacles were reattached on surfaces. Redox activity persisted during the reattachment period. The results reveal surface adsorption processes coupled to the complex secretory and chemical activity under barnacles as they construct

  14. Development of a cyclometalated iridium complex with specific intramolecular hydrogen-bonding that acts as a fluorescent marker for the endoplasmic reticulum and causes photoinduced cell death† †Electronic supplementary information (ESI) available: Detailed synthesis; photophysical data (Table S1); pH dependent phosphorescence lifetime of complex C2 (Table S2); crystallographic parameters of C2; selected bond distances and angles of C2 (Table S3); cyclic voltammetric data of complexes C1–C11 (Table S4); 1H NMR spectra of ligands and complexes (Fig. S1 and S3); ESI-MS spectra of ligands and complexes (Fig. S2 and S4); fluorescence spectra of the complexes in acetonitrile and at pH 4, 7 and 9, exponential decay curve of C2 (Fig. S5); pH dependent fluorescence spectrum of complexes C1–C11 (Fig. S6); DIC and confocal fluorescence images of live MCF7 cells not treated with C2 but exposed to photoirradiation at 405 nm for 30 min; the cells were treated with DCFDA and fluorescence images were obtained at 529 nm after excitation at 495 nm (Fig. S7). ESI videos 1 and 2. CCDC 967841. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c4dt00845f Click here for additional data file. Click here for additional data file. Click here for additional data file. Click here for additional data file. Click here for additional data file.

    PubMed Central

    Mandal, Soumik; Poria, Dipak K.; Ghosh, Ritabrata

    2014-01-01

    Cyclometalated iridium complexes have important applications as phosphorescent probes for cellular imaging due to their photophysical properties. Moreover, these properties also make them potential candidates as photosensitizers for photodynamic therapy (PDT) of tumors and skin diseases. Treatment of MCF7 breast carcinoma cells with a heteroleptic phosphorescent cyclometalated iridium(iii) complex C2 followed by confocal imaging indicates that the complex selectively localizes and exhibits high fluorescence in the endoplasmic reticulum. In an unprecedented approach, systematic alteration of functional groups or the metal core in C2 to synthesize a series of iridium(iii) complexes (C1–C10) and an organometallic rhenium complex C11 with an imidazolyl modified phenanthroline ligand has indicated the functional groups and their interactions that are responsible for this selective localization. Remarkably, the exposure of the cells treated with C2 to irradiation at 405 nm for one hour led to membrane blebbing and cell death, demonstrating a photosensitizing property of the compound. PMID:25341053

  15. Nonlinear dual reconstruction of SPECT activity and attenuation images.

    PubMed

    Liu, Huafeng; Guo, Min; Hu, Zhenghui; Shi, Pengcheng; Hu, Hongjie

    2014-01-01

    In single photon emission computed tomography (SPECT), accurate attenuation maps are needed to perform essential attenuation compensation for high quality radioactivity estimation. Formulating the SPECT activity and attenuation reconstruction tasks as coupled signal estimation and system parameter identification problems, where the activity distribution and the attenuation parameter are treated as random variables with known prior statistics, we present a nonlinear dual reconstruction scheme based on the unscented Kalman filtering (UKF) principles. In this effort, the dynamic changes of the organ radioactivity distribution are described through state space evolution equations, while the photon-counting SPECT projection data are measured through the observation equations. Activity distribution is then estimated with sub-optimal fixed attenuation parameters, followed by attenuation map reconstruction given these activity estimates. Such coupled estimation processes are iteratively repeated as necessary until convergence. The results obtained from Monte Carlo simulated data, physical phantom, and real SPECT scans demonstrate the improved performance of the proposed method both from visual inspection of the images and a quantitative evaluation, compared to the widely used EM-ML algorithms. The dual estimation framework has the potential to be useful for estimating the attenuation map from emission data only and thus benefit the radioactivity reconstruction. PMID:25225796

  16. Nonlinear Dual Reconstruction of SPECT Activity and Attenuation Images

    PubMed Central

    Liu, Huafeng; Guo, Min; Hu, Zhenghui; Shi, Pengcheng; Hu, Hongjie

    2014-01-01

    In single photon emission computed tomography (SPECT), accurate attenuation maps are needed to perform essential attenuation compensation for high quality radioactivity estimation. Formulating the SPECT activity and attenuation reconstruction tasks as coupled signal estimation and system parameter identification problems, where the activity distribution and the attenuation parameter are treated as random variables with known prior statistics, we present a nonlinear dual reconstruction scheme based on the unscented Kalman filtering (UKF) principles. In this effort, the dynamic changes of the organ radioactivity distribution are described through state space evolution equations, while the photon-counting SPECT projection data are measured through the observation equations. Activity distribution is then estimated with sub-optimal fixed attenuation parameters, followed by attenuation map reconstruction given these activity estimates. Such coupled estimation processes are iteratively repeated as necessary until convergence. The results obtained from Monte Carlo simulated data, physical phantom, and real SPECT scans demonstrate the improved performance of the proposed method both from visual inspection of the images and a quantitative evaluation, compared to the widely used EM-ML algorithms. The dual estimation framework has the potential to be useful for estimating the attenuation map from emission data only and thus benefit the radioactivity reconstruction. PMID:25225796

  17. Voltage-Sensitive Dye Imaging of Neocortical Activity.

    PubMed

    Grinvald, Amiram; Omer, David B; Sharon, Dahlia; Vanzetta, Ivo; Hildesheim, Rina

    2016-01-01

    Neural computations underlying sensory perception, cognition, and motor control are performed by populations of neurons at different anatomical and temporal scales. Few techniques are currently available for exploring the dynamics of local and large range populations. Voltage-sensitive dye imaging (VSDI), based on organic voltage probes, reveals neural population activity in areas ranging from a few tens of micrometers to a couple of centimeters, or two areas up to ~10 cm apart. VSDI provides a submillisecond temporal resolution and a spatial resolution of ~50 µm. The dye signal emphasizes subthreshold synaptic potentials. VSDI has been applied in the mouse, rat, gerbil, ferret, tree shrew, cat, and monkey cortices to explore the lateral spread of retinotopic or somatotopic activation; the dynamic spatiotemporal pattern resulting from sensory activation, including the somatosensory, olfactory, auditory, and visual modalities; and motor preparation and the properties of spontaneously occurring population activity. In this introduction, we focus on VSDI in vivo and review results obtained mostly in the visual system in our laboratory. PMID:26729915

  18. Identification, purification and characterization of a novel collagenolytic serine protease from fig (Ficus carica var. Brown Turkey) latex.

    PubMed

    Raskovic, Brankica; Bozovic, Olga; Prodanovic, Radivoje; Niketic, Vesna; Polovic, Natalija

    2014-12-01

    A novel collagenolytic serine protease was identified and then purified (along with ficin) to apparent homogeneity from the latex of fig (Ficus carica, var. Brown Turkey) by two step chromatographic procedure using gel and covalent chromatography. The enzyme is a monomeric protein of molecular mass of 41 ± 9 kDa as estimated by analytical gel filtration chromatography. It is an acidic protein with a pI value of approximately 5 and optimal activity at pH 8.0-8.5 and temperature 60°C. The enzymatic activity was strongly inhibited by PMSF and Pefabloc SC, indicating that the enzyme is a serine protease. The enzyme showed specificity towards gelatin and collagen (215 GDU/mg and 24.8 CDU/mg, respectively) and non-specific protease activity (0.18 U/mg against casein). The enzyme was stable and retained full activity over a broad range of pH and temperature. The fig latex collagenolytic protease is potentially useful as a non-microbial enzyme with collagenolytic activity for various applications in the fields of biochemistry, biotechnology and medicine. PMID:24982021

  19. Metatranscriptome Analysis of Fig Flowers Provides Insights into Potential Mechanisms for Mutualism Stability and Gall Induction

    PubMed Central

    Martinson, Ellen O.; Hackett, Jeremiah D.; Machado, Carlos A.; Arnold, A. Elizabeth

    2015-01-01

    A striking property of the mutualism between figs and their pollinating wasps is that wasps consistently oviposit in the inner flowers of the fig syconium, which develop into galls that house developing larvae. Wasps typically do not use the outer ring of flowers, which develop into seeds. To better understand differences between gall and seed flowers, we used a metatranscriptomic approach to analyze eukaryotic gene expression within fig flowers at the time of oviposition choice and early gall development. Consistent with the unbeatable seed hypothesis, we found significant differences in gene expression between gall- and seed flowers in receptive syconia prior to oviposition. In particular, transcripts assigned to flavonoids and carbohydrate metabolism were significantly up-regulated in gall flowers relative to seed flowers. In response to oviposition, gall flowers significantly up-regulated the expression of chalcone synthase, which previously has been connected to gall formation in other plants. We propose several genes encoding proteins with signal peptides or associations with venom of other Hymenoptera as candidate genes for gall initiation or growth. This study simultaneously evaluates the gene expression profile of both mutualistic partners in a plant-insect mutualism and provides insight into a possible stability mechanism in the ancient fig-fig wasp association. PMID:26090817

  20. Range-gated intensified spectrographic imager: an instrument for active hyperspectral imaging

    NASA Astrophysics Data System (ADS)

    Simard, Jean-Robert; Mathieu, Pierre; Fournier, Georges R.; Larochelle, Vincent; Babey, Stephen K.

    2000-09-01

    Hyperspectral imaging has demonstrated impressive capabilities in airborne surveys, particularly for mineral and biomass characterizations. Based on this success, it is believed that other applications like search and rescue operations, and detection/identification of various ground military targets could greatly benefit from this technology. The strength of hyperspectral imaging comes from the access to another dimension of information: the spectral content of the detected return signal for each spatial pixel. In the case of conventional hyperspectral imaging, the return signal depicts the spectral reflectance of the day irradiance from the scene within the field of view of each pixel. However, by inserting a range-gated intensifier into a hyperspectral camera and by combining the camera with selected pulsed lasers, it becomes possible to relate the returned spectral information to specific light/matter interactions like induced fluorescence. This new technique may be referred to as 'active hyperspectral imaging.' Among its advantages, this approach is independent of the ambient lighting conditions and can be customized in excitation wavelengths. Moreover, by using a range-gated intensified camera, it is possible to survey limited area with a significant increase in signal-to-noise ratio. A camera of this type has been built by our group in collaboration with private industry and is described in this paper. The internal design of the camera is discussed, new issues concerning the calibration of the camera are depicted and a model based on signal-to-noise ratio analysis is presented. From the fluorescent characteristics of surrogate land mines measured in the laboratory, this model is used to predict the capabilities of detecting surface-laid mines from an aerial platform based scenario.

  1. Imaging hypothalamic activity using diffusion weighted magnetic resonance imaging in the mouse and human brain.

    PubMed

    Lizarbe, Blanca; Benítez, Ania; Sánchez-Montañés, Manuel; Lago-Fernández, Luis F; Garcia-Martin, María L; López-Larrubia, Pilar; Cerdán, Sebastián

    2013-01-01

    Hypothalamic appetite regulation is a vital homeostatic process underlying global energy balance in animals and humans, its disturbances resulting in feeding disorders with high morbidity and mortality. The objective evaluation of appetite remains difficult, very often restricted to indirect measurements of food intake and body weight. We report here, the direct, non-invasive visualization of hypothalamic activation by fasting using diffusion weighted magnetic resonance imaging, in the mouse brain as well as in a preliminary study in the human brain. The brain of fed or fasted mice or humans were imaged at 7 or 1.5 Tesla, respectively, by diffusion weighted magnetic resonance imaging using a complete range of b values (10image data sets were registered and analyzed pixel by pixel using a biexponential model of diffusion, or a model-free Linear Discriminant Analysis approach. Biexponential fittings revealed statistically significant increases in the slow diffusion parameters of the model, consistent with a neurocellular swelling response in the fasted hypothalamus. Increased resolution approaches allowed the detection of increases in the diffusion parameters within the Arcuate Nucleus, Ventromedial Nucleus and Dorsomedial Nucleus. Independently, Linear Discriminant Analysis was able to classify successfully the diffusion data sets from mice and humans between fed and fasted states. Present results are consistent with increased glutamatergic neurotransmission during orexigenic firing, a process resulting in increased ionic accumulation and concomitant osmotic neurocellular swelling. This swelling response is spatially extendable through surrounding astrocytic networks until it becomes MRI detectable. Present findings open new avenues for the direct, non-invasive, evaluation of appetite disorders and other hypothalamic pathologies helping potentially in the development of the corresponding therapies. PMID:23000787

  2. Imaging Microglial Activation with TSPO PET: Lighting Up Neurologic Diseases?

    PubMed

    Vivash, Lucy; O'Brien, Terence J

    2016-02-01

    Neuroinflammation is implicated in the pathogenesis of a wide range of neurologic and neuropsychiatric diseases. For over 20 years, (11)C-PK11195 PET, which aims to image expression of the translocator protein (TSPO) on activated microglia in the brain, has been used in preclinical and clinical research to investigate neuroinflammation in vivo in patients with brain diseases. However, (11)C-PK11195 suffers from two major limitations: its low brain permeability and high nonspecific and plasma binding results in a low signal-to-noise ratio, and the use of (11)C restricts its use to PET research centers and hospitals with an on-site cyclotron. In recent years, there has been a great deal of work into the development of new TSPO-specific PET radiotracers. This work has focused on fluorinated radiotracers, which would enable wider use and improved signal-to-noise ratios. These radiotracers have been utilized in preclinical and clinical studies of several neurologic diseases with varying degrees of success. Unfortunately, the application of these second-generation TSPO radiotracers has revealed additional problems, including a polymorphism that affects TSPO binding. In this review, the developments in TSPO imaging are discussed, and current limitations and suggestions for future directions are explored. PMID:26697963

  3. Nucleocapsid Protein from Fig Mosaic Virus Forms Cytoplasmic Agglomerates That Are Hauled by Endoplasmic Reticulum Streaming

    PubMed Central

    Ishikawa, Kazuya; Miura, Chihiro; Maejima, Kensaku; Komatsu, Ken; Hashimoto, Masayoshi; Tomomitsu, Tatsuya; Fukuoka, Misato; Yusa, Akira; Yamaji, Yasuyuki

    2014-01-01

    ABSTRACT Although many studies have demonstrated intracellular movement of viral proteins or viral replication complexes, little is known about the mechanisms of their motility. In this study, we analyzed the localization and motility of the nucleocapsid protein (NP) of Fig mosaic virus (FMV), a negative-strand RNA virus belonging to the recently established genus Emaravirus. Electron microscopy of FMV-infected cells using immunogold labeling showed that NPs formed cytoplasmic agglomerates that were predominantly enveloped by the endoplasmic reticulum (ER) membrane, while nonenveloped NP agglomerates also localized along the ER. Likewise, transiently expressed NPs formed agglomerates, designated NP bodies (NBs), in close proximity to the ER, as was the case in FMV-infected cells. Subcellular fractionation and electron microscopic analyses of NP-expressing cells revealed that NBs localized in the cytoplasm. Furthermore, we found that NBs moved rapidly with the streaming of the ER in an actomyosin-dependent manner. Brefeldin A treatment at a high concentration to disturb the ER network configuration induced aberrant accumulation of NBs in the perinuclear region, indicating that the ER network configuration is related to NB localization. Dominant negative inhibition of the class XI myosins, XI-1, XI-2, and XI-K, affected both ER streaming and NB movement in a similar pattern. Taken together, these results showed that NBs localize in the cytoplasm but in close proximity to the ER membrane to form enveloped particles and that this causes passive movements of cytoplasmic NBs by ER streaming. IMPORTANCE Intracellular trafficking is a primary and essential step for the cell-to-cell movement of viruses. To date, many studies have demonstrated the rapid intracellular movement of viral factors but have failed to provide evidence for the mechanism or biological significance of this motility. Here, we observed that agglomerates of nucleocapsid protein (NP) moved rapidly

  4. Finding hidden females in a crowd: Mate recognition in fig wasps

    NASA Astrophysics Data System (ADS)

    Krishnan, Anusha; Joshi, Kanchan Anand; Abraham, Ambily; Ayyub, Shreya; Lahiry, Mohini; Mukherjee, Ritwika; Javadekar, Saniya Milind; Narayan, Vignesh; Borges, Renee M.

    2014-05-01

    Multi-species mating aggregations are crowded environments within which mate recognition must occur. Mating aggregations of fig wasps can consist of thousands of individuals of many species that attain sexual maturity simultaneously and mate in the same microenvironment, i.e, in syntopy, within the close confines of an enclosed globular inflorescence called a syconium - a system that has many signalling constraints such as darkness and crowding. All wasps develop within individual galled flowers. Since mating mostly occurs when females are still confined within their galls, male wasps have the additional burden of detecting conspecific females that are "hidden" behind barriers consisting of gall walls. In Ficus racemosa, we investigated signals used by pollinating fig wasp males to differentiate conspecific females from females of other syntopic fig wasp species. Male Ceratosolen fusciceps could detect conspecific females using cues from galls containing females, empty galls, as well as cues from gall volatiles and gall surface hydrocarbons.

  5. Radiation processing as a post-harvest quarantine control for raisins, dried figs and dried apricots

    NASA Astrophysics Data System (ADS)

    Cetinkaya, N.; Ozyardımci, B.; Denli, E.; Ic, E.

    2006-03-01

    The commercially packed samples of raisins, dried figs and dried apricots were irradiated using doses in the range of 0.5-1.0 kGy for disinfestation and 0.5-5.0 kGy for sensory analysis with the dose rate ranging from 1.44 to 1.92 kGy/h. Pests on dried fruits were evaluated after 0, 1, 2 and 3 months of storage for irradiated dried figs and 1, 3, 6 and 12 months of storage for raisins and dried apricots. Sensory analysis of dried figs, dried apricots and raisins were carried out after 0, 1, 3, 6 and 12 months of storage. The results indicated that radiation processing at low doses, (˜1.0 kGy) is an effective post-harvest treatment and quarantine control for these products with no adverse effects on sensory (marketing) attributes.

  6. Aberrant Activity in Degenerated Retinas Revealed by Electrical Imaging

    PubMed Central

    Zeck, Günther

    2016-01-01

    In this review, I present and discuss the current understanding of aberrant electrical activity found in the ganglion cell layer (GCL) of rod-degenerated (rd) mouse retinas. The reported electrophysiological properties revealed by electrical imaging using high-density microelectrode arrays can be subdivided between spiking activity originating from retinal ganglion cells (RGCs) and local field potentials (LFPs) reflecting strong trans-membrane currents within the GCL. RGCs in rd retinas show increased and rhythmic spiking compared to age-matched wild-type retinas. Fundamental spiking frequencies range from 5 to 15 Hz in various mouse models. The rhythmic RGC spiking is driven by a presynaptic network comprising AII amacrine and bipolar cells. In the healthy retina this rhythm-generating circuit is inhibited by photoreceptor input. A unique physiological feature of rd retinas is rhythmic LFP manifested as spatially-restricted low-frequency (5–15 Hz) voltage changes. Their spatiotemporal characterization revealed propagation and correlation with RGC spiking. LFPs rely on gap-junctional coupling and are shaped by glycinergic and by GABAergic transmission. The aberrant RGC spiking and LFPs provide a simple readout of the functionality of the remaining retinal circuitry which can be used in the development of improved vision restoration strategies. PMID:26903810

  7. Using the One Degree Imager to Study Active Asteroids

    NASA Astrophysics Data System (ADS)

    Brunker, Samantha; Rajagopal, Jayadev; Ridgway, Susan E.

    2015-01-01

    Active asteroids are asteroids that eject material, which can be caused by several different mechanisms that act on the asteroid, such as collisions, rotational instability, or radiation pressure. We study these asteroids in order to better understand these ejection mechanisms, and gauge their contribution to the zodiacal dust in the Solar System. For this project at the NOAO/KPNO REU program, we chose to focus on two specific asteroids, P/2010 A2 and 300160. Both asteroids were observed with the partial One Degree Imager on the WIYN 3.5 meter telescope on Kitt Peak. P/2010 A2 has an impressive debris tail made up of ejected dust that stretches for over a million kilometers. The wide field of pODI allowed us to construct a surface brightness profile for almost the entire extent of the tail. From this we can investigate the ejection mechanisms that caused the tail to form, and estimate the dust mass. For 300163 we did follow up observations to search for any current activity. We did not identify any trace of nebulosity in our data which indicate that the previously seen nebulosity was part of a transient event. This gives us clues about the possible ejection mechanisms acting on 300163.S. Brunker was supported by the NOAO/KPNO Research Experiences for Undergraduates Program which is funded by the National Science Foundation Research Experiences for Undergraduates Program (AST-1262829).

  8. GRID based Thermal Images Processing for volcanic activity monitoring

    NASA Astrophysics Data System (ADS)

    Mangiagli, S.; Coco, S.; Drago, L.; Laudani, A.,; Lodato, L.; Pollicino, G.; Torrisi, O.

    2009-04-01

    Since 2001, the Catania Section of the National Institute of Geophysics and Volcanology (INGV) has been running the video stations recording the volcanic activity of Mount Etna, Stromboli and the Fossa Crater of Vulcano island. The video signals of 11 video cameras (seven operating in the visible band and four in infrared) are sent in real time to INGV Control Centre where they are visualized on monitors and archived on a dedicated NAS storage. The video surveillance of the Sicilian volcanoes, situated near to densely populated areas, helps the volcanologists providing the Civil Protection authorities with updates in real time on the on-going volcanic activity. In particular, five video cameras are operating on Mt. Etna and they record the volcano from the south and east sides 24 hours a day. During emergencies, mobile video stations may also be used to better film the most important phases of the activity. Single shots are published on the Catania Section intranet and internet websites. On June 2006 a A 40 thermal camera was installed in Vulcano La Fossa Crater. The location was in the internal and opposite crater flank (S1), 400 m distant from the fumarole field. The first two-year of data on temperature distribution frequency were recorded with this new methodology of acquisition, and automatically elaborated by software at INGV Catania Section. In fact a dedicated software developed in IDL, denominated Volcano Thermo Analysis (VTA), was appositely developed in order to extract a set of important features, able to characterize with a good approssimation the volcanic activity. In particular the program first load and opportunely convert the thermal images, then according to the Region Of Interest (ROI) and the temperature ranges defined by the user provide to automatic spatial and statistic analysis. In addition the VTA is able to analysis all the temporal series of images available in order to achieve the time-event analysis and the dynamic of the volcanic

  9. Spatial Distribution of Crown Gall in a Commercial Nursery of Weeping Fig

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agrobacterium larrymoorei causes tumors on the trunk and branches of weeping fig (Ficus benjamina L.). The extent to which this pathogen is spread through the mother tree planting and transmitted to daughter branches during the process of propagation was studied in a commercial nursery in 2007 and 2...

  10. Non-quantitative adjustment of offspring sex ratios in pollinating fig wasps

    PubMed Central

    Wang, Rui-Wu; Sun, Bao-Fa; He, Jun-Zhou; Dunn, Derek W.

    2015-01-01

    Fig wasp is one of the most well known model systems in examining whether or not the parents could adjust their offspring sex ratio to maximize their gene frequency transmission in next generations. Our manipulative experiments showed that, in all of the five pollinator wasps of figs (Agaonidae) that have different averages of foundress numbers per syconium, almost the same proportions of male offspring are produced in the experiment that foundresses deposit one hour then are killed with ether (66.1%–70.1%) and over the lifespan of each foundress (14.0%–21.0%). The foundresses tend to deposit their male eggs prior to female eggs. The observed increase in the proportion of male offspring as a function of foundress number results from density-dependent interference competition among the foundresses. These results showed that the selection of gene frequency transmission through the behavioral adjustment in the evolution of sex ratio does not exist in these five fig wasps. The results here implied that genetic adjustment mechanisms of the sex ratio of fig wasps can only be triggered to be on or off and that the foundresses can not quantitatively adjust their sex ratio according to increased environmental selection pressure. PMID:26293349

  11. New Plant-Parasitic Nematode from the Mostly Mycophagous Genus Bursaphelenchus Discovered inside Figs in Japan

    PubMed Central

    Kanzaki, Natsumi; Tanaka, Ryusei; Giblin-Davis, Robin M.; Davies, Kerrie A.

    2014-01-01

    A new nematode species, Bursaphelenchus sycophilus n. sp. is described. The species was found in syconia of a fig species, Ficus variegata during a field survey of fig-associated nematodes in Japan. Because it has a well-developed stylet and pharyngeal glands, the species is considered an obligate plant parasite, and is easily distinguished from all other fungal-feeding species in the genus based upon these characters. Although B. sycophilus n. sp. shares an important typological character, male spicule possessing a strongly recurved condylus, with the “B. eremus group” and the “B. leoni group” of the genus, it was inferred to be monophyletic with the “B. fungivorus group”. The uniquely shaped stylet and well-developed pharyngeal glands is reminiscent of the fig-floret parasitic but paraphyletic assemblage of “Schistonchus”. Thus, these morphological characters appear to be an extreme example of convergent evolution in the nematode family, Aphelenchoididae, inside figs. Other characters shared by the new species and its close relatives, i.e., lack of ventral P1 male genital papilla, female vulval flap, and papilla-shaped P4 genital papillae in males, corroborate the molecular phylogenetic inference. The unique biological character of obligate plant parasitism and highly derived appearance of the ingestive organs of Bursaphelenchus sycophilus n. sp. expands our knowledge of the potential morphological, physiological and developmental plasticity of the genus Bursaphelenchus. PMID:24940595

  12. Global focused identification of germplasm strategy (figs) application on Trifolium epens L.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Trifolium repens L. is a legume species extensively used in grass pastures. Traits such as level of cyanogenic glucosides and flower production are important in breeding productive and nutritious varieties. The Focused Identification of Germplasm Strategy (FIGS) is an approach used to screen large g...

  13. Trapping African fig fly (Diptera: Drosophilidae) with combinations of vinegar and wine

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The African fig fly, Zaprionus indianus Gupta (Diptera: Drosophilidae), is an invasive fruit pest that has spread rapidly through much of the eastern United States. Tests were conducted in southern Florida that recorded the response of Z. indianus to baits that included Merlot wine, rice vinegar, et...

  14. Riparian Ficus Tree Communities: The Distribution and Abundance of Riparian Fig Trees in Northern Thailand

    PubMed Central

    Pothasin, Pornwiwan; Compton, Stephen G.; Wangpakapattanawong, Prasit

    2014-01-01

    Fig trees (Ficus) are often ecologically significant keystone species because they sustain populations of the many seed-dispersing animals that feed on their fruits. They are prominent components of riparian zones where they may also contribute to bank stability as well as supporting associated animals. The diversity and distributions of riparian fig trees in deciduous and evergreen forests in Chiang Mai Province, Northern Thailand were investigated in 2010–2012. To record the diversity and abundance of riparian fig trees, we (1) calculated stem density, species richness, and diversity indices in 20×50 m randomly selected quadrats along four streams and (2) measured the distances of individual trees from four streams to determine if species exhibit distinct distribution patterns within riparian zones. A total of 1169 individuals (from c. 4 ha) were recorded in the quadrats, representing 33 Ficus species (13 monoecious and 20 dioecious) from six sub-genera and about 70% of all the species recorded from northern Thailand. All 33 species had at least some stems in close proximity to the streams, but they varied in their typical proximity, with F. squamosa Roxb. and F. ischnopoda Miq the most strictly stream-side species. The riparian forests in Northern Thailand support a rich diversity and high density of Ficus species and our results emphasise the importance of fig tree within the broader priorities of riparian area conservation. Plans to maintain or restore properly functioning riparian forests need to take into account their significance. PMID:25310189

  15. 76 FR 14320 - Importation of Figs and Pomegranates From Chile Under a Systems Approach

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-16

    ...; ] DEPARTMENT OF AGRICULTURE Animal and Plant Health Inspection Service 7 CFR Part 319 RIN 0579-AD38 Importation of Figs and Pomegranates From Chile Under a Systems Approach AGENCY: Animal and Plant Health... production that is registered with the Government of Chile and certified as having a low prevalence...

  16. W-band active imaging by photonics-based synthesizer

    NASA Astrophysics Data System (ADS)

    Kanno, Atsushi; Sekine, Norihiko; Kasamatsu, Akifumi; Yamamoto, Naokatsu

    2016-05-01

    We demonstrate a nondestructive electromagnetic-wave imaging system with a photonics-based W-band synthe- sizer, traveling-wave tube amplifier and focal-plane transistor array in real time manner. High-power amplifier with multi-watts output will enhance the quality of obtained images under transmission and reflection imaging configurations.

  17. Research on the system scheme and experiment for the active laser polarization imaging

    NASA Astrophysics Data System (ADS)

    Fu, Qiang; Duan, Jin; Zhao, Rui; Li, Zheng; Zhang, Su; Zhan, Juntong; Zhu, Yong; Jiang, Hui-Lin

    2015-10-01

    The polarization imaging detection technology increased the polarization information on the basis of the intensity imaging, which is extensive application in the military and civil and other fields. The research present and development trend of polarization imaging detection technology was introduce, the system scheme of the active polarization imaging detection was put forward, and the key technologies such as the polarization information detection, optical system design, polarization radiation calibration and image fusion approach was analyzed. On this basis, detection system by existing equipment of laboratory was set up, and on the different materials such as wood, metal, plastic and goal was detected by polarization imaging to realize the active polarization imaging detection. The results show that image contrast of the metal and man-made objects is higher, the polarization effect is better, which provided the basis on the better performance of the polarization imaging instruments.

  18. Compact laser sources for laser designation, ranging and active imaging

    NASA Astrophysics Data System (ADS)

    Goldberg, Lew; Nettleton, John; Schilling, Brad; Trussel, Ward; Hays, Alan

    2007-04-01

    Recent advances in compact solid sate lasers for laser designation, eye-safe range finding and active imaging are described. Wide temperature operation of a compact Nd:YAG laser was achieved by end pumping and the use of multi-λ diode stacks. Such lasers enabled construction of fully operational 4.7 lb laser designator prototypes generating over 50 mJ at 10-20 Hz PRF. Output pulse energy in excess of 100 mJ was demonstrated in a breadboard version of the end-pumped laser. Eye-safe 1.5 μm lasers based on flash-pumped, low PRF, Monoblock lasers have enabled compact STORM laser range finders that have recently been put into production. To achieve higher optical and electrical efficiency needed for higher PRF operation, Monoblock lasers were end-pumped by a laser diode stack. Laser diode end-pumped Monoblock lasers were operated at 10-20 Hz PRF over a wide temperature range (-20 to +50 °C). Compared with bulk compact solid state lasers, fiber lasers are characterized by lower pulse energy, higher PRF's, shorter pulses and higher electrical efficiency. An example of fiber lasers suitable for LIDAR, and atmospheric measurement applications is described. Eye-safe, low intensity diode pumped solid state green warning laser developed for US Army checkpoint and convoy applications is also described.

  19. Convolutional virtual electric field for image segmentation using active contours.

    PubMed

    Wang, Yuanquan; Zhu, Ce; Zhang, Jiawan; Jian, Yuden

    2014-01-01

    Gradient vector flow (GVF) is an effective external force for active contours; however, it suffers from heavy computation load. The virtual electric field (VEF) model, which can be implemented in real time using fast Fourier transform (FFT), has been proposed later as a remedy for the GVF model. In this work, we present an extension of the VEF model, which is referred to as CONvolutional Virtual Electric Field, CONVEF for short. This proposed CONVEF model takes the VEF model as a convolution operation and employs a modified distance in the convolution kernel. The CONVEF model is also closely related to the vector field convolution (VFC) model. Compared with the GVF, VEF and VFC models, the CONVEF model possesses not only some desirable properties of these models, such as enlarged capture range, u-shape concavity convergence, subject contour convergence and initialization insensitivity, but also some other interesting properties such as G-shape concavity convergence, neighboring objects separation, and noise suppression and simultaneously weak edge preserving. Meanwhile, the CONVEF model can also be implemented in real-time by using FFT. Experimental results illustrate these advantages of the CONVEF model on both synthetic and natural images. PMID:25360586

  20. Large-scale diversification without genetic isolation in nematode symbionts of figs

    PubMed Central

    Susoy, Vladislav; Herrmann, Matthias; Kanzaki, Natsumi; Kruger, Meike; Nguyen, Chau N.; Rödelsperger, Christian; Röseler, Waltraud; Weiler, Christian; Giblin-Davis, Robin M.; Ragsdale, Erik J.; Sommer, Ralf J.

    2016-01-01

    Diversification is commonly understood to be the divergence of phenotypes accompanying that of lineages. In contrast, alternative phenotypes arising from a single genotype are almost exclusively limited to dimorphism in nature. We report a remarkable case of macroevolutionary-scale diversification without genetic divergence. Upon colonizing the island-like microecosystem of individual figs, symbiotic nematodes of the genus Pristionchus accumulated a polyphenism with up to five discrete adult morphotypes per species. By integrating laboratory and field experiments with extensive genotyping of individuals, including the analysis of 49 genomes from a single species, we show that rapid filling of potential ecological niches is possible without diversifying selection on genotypes. This uncoupling of morphological diversification and speciation in fig-associated nematodes has resulted from a remarkable expansion of discontinuous developmental plasticity. PMID:26824073

  1. Large-scale diversification without genetic isolation in nematode symbionts of figs.

    PubMed

    Susoy, Vladislav; Herrmann, Matthias; Kanzaki, Natsumi; Kruger, Meike; Nguyen, Chau N; Rödelsperger, Christian; Röseler, Waltraud; Weiler, Christian; Giblin-Davis, Robin M; Ragsdale, Erik J; Sommer, Ralf J

    2016-01-01

    Diversification is commonly understood to be the divergence of phenotypes accompanying that of lineages. In contrast, alternative phenotypes arising from a single genotype are almost exclusively limited to dimorphism in nature. We report a remarkable case of macroevolutionary-scale diversification without genetic divergence. Upon colonizing the island-like microecosystem of individual figs, symbiotic nematodes of the genus Pristionchus accumulated a polyphenism with up to five discrete adult morphotypes per species. By integrating laboratory and field experiments with extensive genotyping of individuals, including the analysis of 49 genomes from a single species, we show that rapid filling of potential ecological niches is possible without diversifying selection on genotypes. This uncoupling of morphological diversification and speciation in fig-associated nematodes has resulted from a remarkable expansion of discontinuous developmental plasticity. PMID:26824073

  2. Active Millimeter-Wave and Sub-Millimeter-Wave Imaging for Security Applications

    SciTech Connect

    Sheen, David M.; McMakin, Douglas L.; Hall, Thomas E.

    2011-09-02

    Active imaging at millimeter and sub-millimeter wavelengths has been developed for security applications including concealed weapon detection. The physical properties that affect imaging performance are discussed along with a review of the current state-of-the-art and future potential for security imaging systems.

  3. New insights into the phylogeny of fig pollinators using Bayesian analyses.

    PubMed

    Jiang, Zi-Feng; Huang, Da-Wei; Zhu, Chao-Dong; Zhen, Wen-Quan

    2006-02-01

    The interaction between figs and fig pollinators is one of the most species-specific mutualisms. Recently, phylogenies of both partners based on molecular data provided insights into a wide spectrum of co-evolutionary questions. However, for the phylogeny of fig pollinators, there are some discrepancies between different studies and left some relationships unresolved, especially for deep nodes. The phylogenetic uncertainties of pollinators prohibit our further understanding of the history of the mutualism. Here, we present phylogenetic analyses of a larger COI sequence dataset that includes previously published datasets and our sequences from 20 species using Bayesian method and maximum parsimony. The analyses using different methods share similar topologies. Bayesian analyses provide high level of confidence for most internal nodes in terms of posterior probability. This study also clarifies some discrepancies between previous studies. After rooting with Tetrapus, other pollinators split into two clades. Wiebesia and Blastophaga are at basal positions in respective clade. Ceratosolen is not monophyletic because Kradibia and Liporrhopalum fall inside this group. Three subgenera of Ceratosolen: subgen. Ceratosolen, subgen. Rothropus, and subgen. Strepitus are not supported. Therefore, Ceratosolen is suggested to be re-divided into three groups. Urostigma pollinators (including Dolichoris and Blastophaga psenes) are clustered together. The monophylies of Wiebesia, Blastophaga, Dolichoris are not supported in this analysis. This study also provides a new framework for re-evaluating character evolution and re-inspecting the definition of some genera. PMID:16364663

  4. Influence of harvesting and drying techniques on microflora and mycotoxin contamination of figs.

    PubMed

    Ozay, G; Aran, N; Pala, M

    1995-01-01

    Mould growth and mycotoxin (aflatoxins and ochratoxin A) formation were examined in the 1993 dried figs crop. The relationships between mould/mycotoxin contamination and orchard conditions, different harvesting techniques, harvesting time and intactness of fruits were investigated. The fruits were examined during drying and effects of different pretreatments, sun drying and solar drying on the mould and mycotoxin contamination in figs were also studied. Aflatoxins (B1, B2, G1 and G2) were not present in the firm or shrivelled ripe figs. Among the samples examined during drying, only one of the 32 samples was found to be aflatoxin positive. Ochratoxin A was not detected in any of the samples analysed. The moisture content, aw and pH values of full ripe and shrivelled fruits were suitable for mould growth and mycotoxin formation while these parameters in pretreated and dried fruits were found to be too low to allow such outcome. It was observed that harvesting the fruit by hand-treating with different solutions and application of solar drying were effective in reducing contamination level. PMID:7783781

  5. Color and antioxidant characteristics of some fresh fig (Ficus carica L.) genotypes from northeastern Turkey.

    PubMed

    Ercisli, Sezai; Tosun, Murat; Karlidag, Huseyin; Dzubur, Ahmed; Hadziabulic, Semina; Aliman, Yasmina

    2012-09-01

    Fruit skin color, total phenolics, total anthocyanins, soluble solids content, titratable acidity and total antioxidant capacity in fresh fruits of a number of local and well-known fig (Ficus carica L.) genotypes and cultivars grown in northeastern Turkey were determined. TEAC (Trolox equivalent antioxidant capacity) and FRAP (ferric reducing antioxidant power) assays were used to determine total antioxidant capacity. Fruit skin color of genotypes were found to be very diverse, i.e., light green, light purple, purple, dark purple and black. The content of total phenolics, soluble solids content (SSC) and titratable acidity greatly varied in the range from 24 to 237 mg of gallic acid equivalent per 100 g fresh weight, 18.60 to 26.30 % and 0.16 to 0.47 % in local genotypes and studied cultivars. In general, total antioxidant capacities determined by two methods expressed higher values in the local fig genotypes compared with the cultivars. The results suggested that genotype is the main factor that determines difference in the composition of bioactive compounds in figs and provide information on putative health benefits locally grown genotypes. PMID:22618081

  6. Images.

    ERIC Educational Resources Information Center

    Barr, Catherine, Ed.

    1997-01-01

    The theme of this month's issue is "Images"--from early paintings and statuary to computer-generated design. Resources on the theme include Web sites, CD-ROMs and software, videos, books, and others. A page of reproducible activities is also provided. Features include photojournalism, inspirational Web sites, art history, pop art, and myths. (AEF)

  7. In vivo stepwise multi-photon activation fluorescence imaging of melanin in human skin

    NASA Astrophysics Data System (ADS)

    Lai, Zhenhua; Gu, Zetong; Abbas, Saleh; Lowe, Jared; Sierra, Heidy; Rajadhyaksha, Milind; DiMarzio, Charles

    2014-03-01

    The stepwise multi-photon activated fluorescence (SMPAF) of melanin is a low cost and reliable method of detecting melanin because the activation and excitation can be a continuous-wave (CW) mode near infrared (NIR) laser. Our previous work has demonstrated the melanin SMPAF images in sepia melanin, mouse hair, and mouse skin. In this study, we show the feasibility of using SMPAF to detect melanin in vivo. in vivo melanin SMPAF images of normal skin and benign nevus are demonstrated. SMPAF images add specificity for melanin detection than MPFM images and CRM images. Melanin SMPAF is a promising technology to enable early detection of melanoma for dermatologists.

  8. Real-time intravital imaging of pH variation associated with osteoclast activity.

    PubMed

    Maeda, Hiroki; Kowada, Toshiyuki; Kikuta, Junichi; Furuya, Masayuki; Shirazaki, Mai; Mizukami, Shin; Ishii, Masaru; Kikuchi, Kazuya

    2016-08-01

    Intravital imaging by two-photon excitation microscopy (TPEM) has been widely used to visualize cell functions. However, small molecular probes (SMPs), commonly used for cell imaging, cannot be simply applied to intravital imaging because of the challenge of delivering them into target tissues, as well as their undesirable physicochemical properties for TPEM imaging. Here, we designed and developed a functional SMP with an active-targeting moiety, higher photostability, and a fluorescence switch and then imaged target cell activity by injecting the SMP into living mice. The combination of the rationally designed SMP with a fluorescent protein as a reporter of cell localization enabled quantitation of osteoclast activity and time-lapse imaging of its in vivo function associated with changes in cell deformation and membrane fluctuations. Real-time imaging revealed heterogenic behaviors of osteoclasts in vivo and provided insights into the mechanism of bone resorption. PMID:27272564

  9. CMOS active pixel sensor type imaging system on a chip

    NASA Technical Reports Server (NTRS)

    Fossum, Eric R. (Inventor); Nixon, Robert (Inventor)

    2011-01-01

    A single chip camera which includes an .[.intergrated.]. .Iadd.integrated .Iaddend.image acquisition portion and control portion and which has double sampling/noise reduction capabilities thereon. Part of the .[.intergrated.]. .Iadd.integrated .Iaddend.structure reduces the noise that is picked up during imaging.

  10. Integrated imaging sensor systems with CMOS active pixel sensor technology

    NASA Technical Reports Server (NTRS)

    Yang, G.; Cunningham, T.; Ortiz, M.; Heynssens, J.; Sun, C.; Hancock, B.; Seshadri, S.; Wrigley, C.; McCarty, K.; Pain, B.

    2002-01-01

    This paper discusses common approaches to CMOS APS technology, as well as specific results on the five-wire programmable digital camera-on-a-chip developed at JPL. The paper also reports recent research in the design, operation, and performance of APS imagers for several imager applications.

  11. Images as Orienting Activity: Using Theory to Inform Classroom Practices

    ERIC Educational Resources Information Center

    Feryok, Anne; Pryde, Michael

    2012-01-01

    Conceptualizations of teacher knowledge have shifted to focusing on the role of experiential rather than theoretical knowledge. There are different approaches to this, but the idea of an image that guides practice is widespread. One approach to images that has not been frequently investigated in studies of second language teachers is through…

  12. Planar and cylindrical active microwave temperature imaging: numerical simulations.

    PubMed

    Rius, J M; Pichot, C; Jofre, L; Bolomey, J C; Joachimowicz, N; Broquetas, A; Ferrando, M

    1992-01-01

    A comparative study at 2.45 GHz concerning both measurement and reconstruction parameters for planar and cylindrical configurations is presented. For the sake of comparison, a numerical model consisting of two nonconcentric cylinders is considered and reconstructed using both geometries from simulated experimental data. The scattered fields and reconstructed images permit extraction of very useful information about dynamic range, sensitivity, resolution, and quantitative image accuracy for the choice of the configuration in a particular application. Both geometries can measure forward and backward scattered fields. The backscattering measurement improves the image resolution and reconstruction in lossy mediums, but, on the other hand, has several dynamic range difficulties. This tradeoff between forward only and forward-backward field measurement is analyzed. As differential temperature imaging is a weakly scattering problem, Born approximation algorithms can be used. The simplicity of Born reconstruction algorithms and the use of FFT make them very attractive for real-time biomedical imaging systems. PMID:18222887

  13. An active learning approach to the physics of medical imaging.

    PubMed

    Wilhjelm, Jens E; Pihl, Michael Johannes; Lonsdale, Markus Nowak; Jensen, Mikael

    2008-06-01

    This paper describes an experimentally oriented medical imaging course where the students record, process and analyse 3D data of an unknown piece of formalin fixed porcine tissue hidden in agar in order to estimate the tissue types present in a selected 2D slice. The recorded planar X-ray, CT, MRI, ultrasound and SPECT images show the tissue in very different ways. The students can only estimate the tissue type by studying the physical principles of the imaging modalities. The true answer is later revealed by anatomical photographs obtained from physical slicing. The paper describes the phantoms and methods used in the course. Sample images recorded with the different imaging modalities are provided. Challenges faced by the students are outlined. Results of the course show high increase in competencies as judged from graded reports, low course drop-out rate, high pass-rate at the exam, high student participation and large student satisfaction. PMID:17716937

  14. Active Shape Model-Based Gait Recognition Using Infrared Images

    NASA Astrophysics Data System (ADS)

    Kim, Daehee; Lee, Seungwon; Paik, Joonki

    We present a gait recognition system using infra-red (IR) images. Since an IR camera is not affected by the intensity of illumination, it is able to provide constant recognition performance regardless of the amount of illumination. Model-based object tracking algorithms enable robust tracking with partial occlusions or dynamic illumination. However, this algorithm often fails in tracking objects if strong edge exists near the object. Replacement of the input image by an IR image guarantees robust object region extraction because background edges do not affect the IR image. In conclusion, the proposed gait recognition algorithm improves accuracy in object extraction by using IR images and the improvements finally increase the recognition rate of gaits.

  15. Active and passive imaging of clothes in the NIR and SWIR regions for reflectivity analysis.

    PubMed

    Grönwall, Christina; Steinvall, Ove; Göhler, Benjamin; Hamoir, Dominique

    2016-07-10

    We perform statistical analysis of data from active and passive imaging sensors in the near infrared (NIR) and short wavelength infrared (SWIR) wavelength bands. The data were obtained from measurements performed on clothing in a field campaign and in the laboratory. We show that reflectivity data from active imaging can be fitted to Gaussian functions, although earlier theory proposes gamma-gamma functions. We analyze the reflectivity data collected during the field campaign and compare that data with data obtained in the laboratory. We focus on the added value of active imaging when combined with passive imaging to distinguish different clothes for friend/foe identification. PMID:27409302

  16. Pectinesterase Inhibitor from Jelly Fig (Ficus awkeotsang Makino) Achene Inhibits Surface Antigen Expression by Human Hepatitis B Virus.

    PubMed

    Huang, Yu-Chuen; Jiang, Chii-Ming; Chen, Yu-Jen; Chen, Yu-Yawn

    2013-01-01

    Pectinesterase inhibitor (PEI) isolated from jelly fig (Ficus awkeotsang Makino) is an edible component of a popular drink consumed in Asia. Hepatitis B virus (HBV) infection is prevalent in Asia, and current treatments for HBV infection need improvement. This study aimed to evaluate the effect of PEI on the surface antigen expression by HBV (HBsAg). Human hepatoma cell lines Hep3B and Huh7 served as in vitro models for assessing the cytotoxicity and HBsAg expression. A culture of primary hepatocytes cultured from mice served as the normal counterpart. Cell viability was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) colorimetric assay. HBsAg expression was evaluated by measuring HBsAg secretion into the culture medium using an enzyme-linked immunosorbent assay. The results showed that PEI did not affect the viability of the human hepatoma cell lines or primary mouse hepatocytes. PEI inhibited the expression of HBsAg in hepatoma cell lines harboring endogenous (Hep3B) and integrated (Huh7) HBV genomes in a concentration- and time-dependent manner, thus implicating a universal activity against HBV gene expression. In conclusion, it suggests that PEI from jelly fig inhibits the expression of human HBsAg in host cells without toxic effects on normal primary hepatocytes. PMID:24302965

  17. Curiosity's Mars Hand Lens Imager (MAHLI): Inital Observations and Activities

    NASA Technical Reports Server (NTRS)

    Edgett, K. S.; Yingst, R. A.; Minitti, M. E.; Robinson, M. L.; Kennedy, M. R.; Lipkaman, L. J.; Jensen, E. H.; Anderson, R. C.; Bean, K. M.; Beegle, L. W.; Carsten, J. L.; Collins, C. L.; Cooper, B.; Deen, R. G.; Gupta, S.

    2013-01-01

    MAHLI (Mars Hand Lens Imager) is a 2-megapixel focusable macro lens color camera on the turret on Curiosity's robotic arm. The investigation centers on stratigraphy, grain-scale texture, structure, mineralogy, and morphology of geologic materials at Curiosity's Gale robotic field site. MAHLI acquires focused images at working distances of 2.1 cm to infinity; for reference, at 2.1 cm the scale is 14 microns/pixel; at 6.9 cm it is 31 microns/pixel, like the Spirit and Opportunity Microscopic Imager (MI) cameras.

  18. Magnetic resonance imaging as a tool for extravehicular activity analysis

    NASA Technical Reports Server (NTRS)

    Dickenson, R.; Lorenz, C.; Peterson, S.; Strauss, A.; Main, J.

    1992-01-01

    The purpose of this research is to examine the value of magnetic resonance imaging (MRI) as a means of conducting kinematic studies of the hand for the purpose of EVA capability enhancement. After imaging the subject hand using a magnetic resonance scanner, the resulting 2D slices were reconstructed into a 3D model of the proximal phalanx of the left hand. Using the coordinates of several landmark positions, one is then able to decompose the motion of the rigid body. MRI offers highly accurate measurements due to its tomographic nature without the problems associated with other imaging modalities for in vivo studies.

  19. Host sex-specific parasites in a functionally dioecious fig: a preference way of adaptation to their hosts

    PubMed Central

    Wang, Qi; Jiang, Zi-Feng; Wang, Ning-xin; Niu, Li-ming; Li, Zi; Huang, Da-Wei

    2013-01-01

    Host–parasites interaction is a common phenomenon in nature. Diffusive coevolution might maintain stable cooperation in a fig–fig wasps system, in which the exploiter might diversify their genotype, phenotype, or behavior as a result of competition with pollinator, whereas the figs change flower syconia, fruits thickness, and syconia structure. In functionally dioecious Ficus auriculata, male figs and female figs contain two types of florets on separate plant, and share high similarities in outside morphology. Apocryptophagus (Sycophaginae, Chalcidoidea, Hymenoptera) is one of few groups of nonpollinating fig wasps that can reproduce within both male and female figs. On the basis of the morphology and DNA barcoding, evidence from partial sequences of mitochondrial cytochrome c oxidase I and nuclear internal transcribed spacer 2, we found that there are two nonsibling Apocryptophagus species living on male and female F. auriculata figs, respectively. We estimated that these two species diverged about 19.2 million years ago. Our study suggests that the host shift from Ficus variegate or Ficus prostrata fig species to male figs is a preference way for Apocryptophagus wasps to adapt to the separation of sexual function in diecious figs. Furthermore, to escape the disadvantage or sanction impact of the host, the exploiter Apocryptophagus wasps can preferably adapt to exploiting each sex of the figs, by changing their oviposition, niche shift, and habitat. PMID:24101987

  20. Rapid analysis of fungal cultures and dried figs for secondary metabolites by LC/TOF-MS.

    PubMed

    Senyuva, Hamide Z; Gilbert, John; Oztürkoğlu, Sebnem

    2008-06-01

    A liquid chromatography-time-of-flight mass spectrometry (LC/TOF-MS) method has been developed for profiling fungal metabolites. The performance of the procedure in terms of mass accuracy, selectivity (specificity) and repeatability was established by spiking aflatoxins, ochratoxins, trichothecenes and other metabolites into blank growth media. After extracting, and carrying out LC/TOF-MS analysis, the standards were correctly identified by searching a specially constructed database of 465 secondary metabolites. To demonstrate the viability of this approach 11 toxigenic and four non-toxigenic fungi from reference collections were grown on various media, for 7-14 days. The method was also applied to two toxigenic fungi, A. flavus (200-138) and A. parasiticus (2999-465) grown on gamma radiation sterilised dried figs, for 7-14 days. The fungal hyphae plus a portion of growth media or portions of dried figs were solvent extracted and analysed by LC/TOF-MS using a rapid resolution microbore LC column. Data processing based on cluster analysis, showed that electrospray ionization (ESI)-TOF-MS could be used to unequivocally identify metabolites in crude extracts. Using the elemental metabolite database, it was demonstrated that from culture collection isolates, anticipated metabolites. The speed and simplicity of the method has meant that levels of these metabolites could be monitored daily in sterilised figs. Over a 14-day period, levels of aflatoxins and kojic acid maximised at 5-6 days, whilst levels of 5-methoxysterigmatocystin remained relatively constant. In addition to the known metabolites expected to be produced by these fungi, roquefortine A, fumagillin, fumigaclavine B, malformins (peptides), aspergillic acid, nigragillin, terrein, terrestric acid and penicillic acid were also identified. PMID:18486645

  1. Functional Imaging of Chemically Active Surfaces with Optical Reporter Microbeads

    PubMed Central

    Ahuja, Punkaj; Nair, Sumitha; Narayan, Sreenath; Gratzl, Miklós

    2015-01-01

    We have developed a novel approach to allow for continuous imaging of concentration fields that evolve at surfaces due to release, uptake, and mass transport of molecules, without significant interference of the concentration fields by the chemical imaging itself. The technique utilizes optical “reporter” microbeads immobilized in a thin layer of transparent and inert hydrogel on top of the surface. The hydrogel has minimal density and therefore diffusion in and across it is like in water. Imaging the immobilized microbeads over time provides quantitative concentration measurements at each location where an optical reporter resides. Using image analysis in post-processing these spatially discrete measurements can be transformed into contiguous maps of the dynamic concentration field across the entire surface. If the microbeads are small enough relative to the dimensions of the region of interest and sparsely applied then chemical imaging will not noticeably affect the evolution of concentration fields. In this work colorimetric optode microbeads a few micrometers in diameter were used to image surface concentration distributions on the millimeter scale. PMID:26332766

  2. Stepwise multi-photon activation fluorescence reveals a new method of melanoma imaging for dermatologists

    NASA Astrophysics Data System (ADS)

    Lai, Zhenhua; Lian, Christine; Ma, Jie; Yu, Jingyi; Gu, Zetong; Rajadhyaksha, Milind; DiMarzio, Charles A.

    2014-02-01

    Previous research has shown that the stepwise multi-photon activated fluorescence (SMPAF) of melanin, activated by a continuous-wave (CW) mode near infrared (NIR) laser, is a low cost and reliable method of detecting melanin. SMPAF images of melanin in a mouse hair and a formalin fixed mouse melanoma were compared with conventional multiphoton fluorescence microscopy (MPFM) images and confocal reflectance microscopy (CRM) images, all of which were acquired at an excitation wavelength of 920 nm, to further prove the effectiveness of SMPAF in detecting melanin. SMPAF images add specificity for melanin detection to MPFM images and CRM images. Melanin SMPAF can be a promising technology to enable melanoma imaging for dermatologists.

  3. Noninvasive Imaging of the High Frequency Brain Activity in Focal Epilepsy Patients

    PubMed Central

    Lu, Yunfeng; Worrell, Gregory A.; Zhang, Huishi Clara; Yang, Lin; Brinkmann, Benjamin; Nelson, Cindy

    2014-01-01

    High frequency (HF) activity represents a potential biomarker of the epileptogenic zone in epilepsy patients, the removal of which is considered to be crucial for seizure-free surgical outcome. We proposed a high frequency source imaging (HFSI) approach to noninvasively image the brain sources of scalp recorded high frequency EEG activity. Both computer simulation and clinical patient data analysis were performed to investigate the feasibility of using the HFSI approach to image the sources of HF activity from noninvasive scalp EEG recordings. The HF activity was identified from high-density scalp recordings after high-pass filtering the EEG data and the EEG segments with HF activity were concatenated together to form repetitive HF activity. Independent component analysis was utilized to extract the components corresponding to the HF activity. Noninvasive EEG source imaging using realistic geometric boundary element head modeling was then applied to image the sources of the pathological HF brain activity. Five medically intractable focal epilepsy patients were studied and the estimated sources were found to be concordant with the surgical resection or intracranial recordings of the patients. The present study demonstrates, for the first time, that source imaging from the scalp HF activity could help to localize the seizure onset zone (SOZ) and provide a novel noninvasive way of studying the epileptic brain in humans. This study also indicates the potential application of studying HF activity in the pre-surgical planning of medically intractable epilepsy patients. PMID:24845275

  4. Direct method of three-dimensional imaging using the multiple-wavelength range-gated active imaging principle.

    PubMed

    Matwyschuk, Alexis

    2016-05-10

    The tomography executed with mono-wavelength active imaging systems uses the recording of several images to restore a three-dimensional (3D) scene. Thus, in order to show the depth in the scene, a different color is attributed to each recorded image. Therefore, the 3D restoration depends on the video frame rate of the camera. By using a multiple-wavelength range-gated active imaging system, it is possible to restore the 3D scene directly in a single image at the moment of recording with a video camera. Each emitted light pulse with a different wavelength corresponds to a visualized zone at a different distance in the scene. The camera shutter opens just once during the emission of light pulses with the different wavelengths. Thus, the restoration can be executed in real time with regard to the video frame rate of the camera. From an analytical model and from a graphical approach, we demonstrated the feasibility of this new method of 3D restoration. The non-overlapping conditions between two consecutive visualized zones are analyzed. The experimental test results confirm these different conditions and validate the theoretical principle to directly restore the 3D scene in a color image with a multiple-wavelength laser source, an RGB filter, and a triggerable intensified camera. PMID:27168293

  5. Research on adaptive segmentation and activity classification method of filamentous fungi image in microbe fermentation

    NASA Astrophysics Data System (ADS)

    Cai, Xiaochun; Hu, Yihua; Wang, Peng; Sun, Dujuan; Hu, Guilan

    2009-10-01

    The paper presents an adaptive segmentation and activity classification method for filamentous fungi image. Firstly, an adaptive structuring element (SE) construction algorithm is proposed for image background suppression. Based on watershed transform method, the color labeled segmentation of fungi image is taken. Secondly, the fungi elements feature space is described and the feature set for fungi hyphae activity classification is extracted. The growth rate evaluation of fungi hyphae is achieved by using SVM classifier. Some experimental results demonstrate that the proposed method is effective for filamentous fungi image processing.

  6. Active Learning in Context-Driven Stream Mining With an Application to Image Mining.

    PubMed

    Tekin, Cem; van der Schaar, Mihaela

    2015-11-01

    We propose an image stream mining method in which images arrive with contexts (metadata) and need to be processed in real time by the image mining system (IMS), which needs to make predictions and derive actionable intelligence from these streams. After extracting the features of the image by preprocessing, IMS determines online the classifier to use on the extracted features to make a prediction using the context of the image. A key challenge associated with stream mining is that the prediction accuracy of the classifiers is unknown, since the image source is unknown; thus, these accuracies need to be learned online. Another key challenge of stream mining is that learning can only be done by observing the true label, but this is costly to obtain. To address these challenges, we model the image stream mining problem as an active, online contextual experts problem, where the context of the image is used to guide the classifier selection decision. We develop an active learning algorithm and show that it achieves regret sublinear in the number of images that have been observed so far. To further illustrate and assess the performance of our proposed methods, we apply them to diagnose breast cancer from the images of cellular samples obtained from the fine needle aspirate of breast mass. Our findings show that very high diagnosis accuracy can be achieved by actively obtaining only a small fraction of true labels through surgical biopsies. Other applications include video surveillance and video traffic monitoring. PMID:26087490

  7. Nuclear magnetic resonance imaging in medicine

    PubMed Central

    McKinstry, C S

    1986-01-01

    Using the technique of nuclear magnetic resonance (NMR, MR, MRI), the first images displaying pathology in humans were published in 1980.1 Since then, there has been a rapid extension in the use of the technique, with an estimated 225 machines in use in the USA at the end of 1985.2 Considerable enthusiasm has been expressed for this new imaging technique,3 although awareness of its high cost in the present economic climate has led to reservations being expressed in other quarters.2 The aim of this article is to give an outline of the present state of NMR, and indicate some possible future developments. ImagesFig 1Fig 2Fig 3(a)Fig 3 (b)Fig 4Fig 5Fig 6Fig 7 (a)Fig 7 (b)Fig 8Fig 9Fig 10 PMID:3811023

  8. Reflectance and Fluorescence Spectral Recovery via Actively Lit RGB Images.

    PubMed

    Fu, Ying; Lam, Antony; Sato, Imari; Okabe, Takahiro; Sato, Yoichi

    2016-07-01

    In recent years, fluorescence analysis of scenes has received attention in computer vision. Fluorescence can provide additional information about scenes, and has been used in applications such as camera spectral sensitivity estimation, 3D reconstruction, and color relighting. In particular, hyperspectral images of reflective-fluorescent scenes provide a rich amount of data. However, due to the complex nature of fluorescence, hyperspectral imaging methods rely on specialized equipment such as hyperspectral cameras and specialized illuminants. In this paper, we propose a more practical approach to hyperspectral imaging of reflective-fluorescent scenes using only a conventional RGB camera and varied colored illuminants. The key idea of our approach is to exploit a unique property of fluorescence: the chromaticity of fluorescent emissions are invariant under different illuminants. This allows us to robustly estimate spectral reflectance and fluorescent emission chromaticity. We then show that given the spectral reflectance and fluorescent chromaticity, the fluorescence absorption and emission spectra can also be estimated. We demonstrate in results that all scene spectra can be accurately estimated from RGB images. Finally, we show that our method can be used to accurately relight scenes under novel lighting. PMID:27295456

  9. IMAGING ASSESSMENT OF G-PROTEIN-COUPLED ESTROGEN RECEPTOR ACTIVATION

    EPA Science Inventory

    We expect to provide a targeted imaging assay that links chemical mechanism of toxicity to target organ effects and heart physiology within individual 96-hpf zebrafish. Importantly, with the utilization of selective, non-toxic agonists or antagonists for additional xenobiot...

  10. Calcium Imaging of Neuronal Activity in Free-Swimming Larval Zebrafish.

    PubMed

    Muto, Akira; Kawakami, Koichi

    2016-01-01

    Visualization of neuronal activity during animal behavior is a critical step in understanding how the brain generates behavior. In the model vertebrate zebrafish, imaging of the brain has been done mostly by using immobilized fish. Here, we describe a novel method to image neuronal activity of the larval zebrafish brain during prey capture behavior. We expressed a genetically encoded fluorescent calcium indicator, GCaMP, in the optic tectum of the midbrain using the Gal4-UAS system. Tectal activity was then imaged in unrestrained larvae during prey perception. Since larval zebrafish swim only intermittently, detection of the neuronal activity is possible between swimming bouts. Our method makes functional brain imaging under natural behavioral conditions feasible and will greatly benefit the study of neuronal activities that evoke animal behaviors. PMID:27464819

  11. Sm-Nd dating of Fig Tree clay minerals of the Barberton greenstone belt, South Africa

    NASA Technical Reports Server (NTRS)

    Toulkeridis, T.; Goldstein, S. L.; Clauer, N.; Kroner, A.; Lowe, D. R.

    1994-01-01

    Sm-Nd isotopic data from carbonate-derived clay minerals of the 3.22-3.25 Ga Fig Tree Group, Barberton greenstone belt, South Africa, form a linear array corresponding to an age of 3102 +/- 64 Ma, making these minerals the oldest dated clays on Earth. The obtained age is 120-160 m.y. younger than the depositional age determined by zircon geochronology. Nd model ages for the clays range from approximately 3.39 to 3.44 Ga and almost cover the age variation of the Barberton greenstone belt rocks, consistent with independent evidence that the clay minerals are derived from material of the belt. The combined isotopic and mineralogical data provide evidence for a cryptic thermal overprint in the sediments of the belt. However, the highest temperature reached by the samples since the time of clay-mineral formation was <300 degrees C, lower than virtually any known early Archean supracrustal sequence.

  12. Sm-Nd dating of Fig Tree clay minerals of the Barberton greenstone belt, South Africa.

    PubMed

    Toulkeridis, T; Goldstein, S L; Clauer, N; Kroner, A; Lowe, D R

    1994-03-01

    Sm-Nd isotopic data from carbonate-derived clay minerals of the 3.22-3.25 Ga Fig Tree Group, Barberton greenstone belt, South Africa, form a linear array corresponding to an age of 3102 +/- 64 Ma, making these minerals the oldest dated clays on Earth. The obtained age is 120-160 m.y. younger than the depositional age determined by zircon geochronology. Nd model ages for the clays range from approximately 3.39 to 3.44 Ga and almost cover the age variation of the Barberton greenstone belt rocks, consistent with independent evidence that the clay minerals are derived from material of the belt. The combined isotopic and mineralogical data provide evidence for a cryptic thermal overprint in the sediments of the belt. However, the highest temperature reached by the samples since the time of clay-mineral formation was <300 degrees C, lower than virtually any known early Archean supracrustal sequence. PMID:11540244

  13. The mechanism of pollinator specificity between two sympatric fig varieties: a combination of olfactory signals and contact cues

    PubMed Central

    Wang, Gang; Compton, Stephen G.; Chen, Jin

    2013-01-01

    Background and Aims Pollinator specificity facilitates reproductive isolation among plants, and mechanisms that generate specificity influence species boundaries. Long-range volatile attractants, in combination with morphological co-adaptations, are generally regarded as being responsible for maintaining extreme host specificity among the fig wasps that pollinate fig trees, but increasing evidence for breakdowns in specificity is accumulating. The basis of host specificity was examined among two host-specific Ceratosolen fig wasps that pollinate two sympatric varieties of Ficus semicordata, together with the consequences for the plants when pollinators entered the alternative host variety. Methods The compositions of floral scents from receptive figs of the two varieties and responses of their pollinators to these volatiles were compared. The behaviour of the wasps once on the surface of the figs was also recorded, together with the reproductive success of figs entered by the two Ceratosolen species. Key Results The receptive-phase floral scents of the two varieties had different chemical compositions, but only one Ceratosolen species displayed a preference between them in Y-tube trials. Specificity was reinforced at a later stage, once pollinators were walking on the figs, because both species preferred to enter figs of their normal hosts. Both pollinators could enter figs of both varieties and pollinate them, but figs with extra-varietal pollen were more likely to abort and contained fewer seeds. Hybrid seeds germinated at normal rates. Conclusions Contact cues on the surface of figs have been largely ignored in previous studies of fig wasp host preferences, but together with floral scents they maintain host specificity among the pollinators of sympatric F. semicordata varieties. When pollinators enter atypical hosts, post-zygotic factors reduce but do not prevent the production of hybrid offspring, suggesting there may be gene flow between these varieties. PMID

  14. Resolution enhancement in active underwater polarization imaging with modulation transfer function analysis.

    PubMed

    Han, Jiefei; Yang, Kecheng; Xia, Min; Sun, Liying; Cheng, Zao; Liu, Hao; Ye, Junwei

    2015-04-10

    Active polarization imaging technology is a convenient and promising method for imaging in a scattering medium such as fog and turbid water. However, few studies have investigated the influence of polarization on the resolution in underwater imaging. This paper reports on the effects of polarization detection on the resolution of underwater imaging by using active polarization imaging technology. An experimental system is designed to determine the influence under various polarization and water conditions. The modulation transfer function is introduced to estimate the resolution variations at different spatial frequencies. Results show that orthogonal detection supplies the best resolution compared with other polarization directions in the turbid water. The performance of the circular polarization method is better than the linear process. However, if the light propagates under low scattering conditions, such as imaging in clean water or at small optical thickness, the resolution enhancement is not sensitive to the polarization angles. PMID:25967316

  15. Loss of Fig4 in both Schwann cells and motor neurons contributes to CMT4J neuropathy

    PubMed Central

    Vaccari, Ilaria; Carbone, Antonietta; Previtali, Stefano Carlo; Mironova, Yevgeniya A.; Alberizzi, Valeria; Noseda, Roberta; Rivellini, Cristina; Bianchi, Francesca; Del Carro, Ubaldo; D'Antonio, Maurizio; Lenk, Guy M.; Wrabetz, Lawrence; Giger, Roman J.; Meisler, Miriam H.; Bolino, Alessandra

    2015-01-01

    Mutations of FIG4 are responsible for Yunis-Varón syndrome, familial epilepsy with polymicrogyria, and Charcot-Marie-Tooth type 4J neuropathy (CMT4J). Although loss of the FIG4 phospholipid phosphatase consistently causes decreased PtdIns(3,5)P2 levels, cell-specific sensitivity to partial loss of FIG4 function may differentiate FIG4-associated disorders. CMT4J is an autosomal recessive neuropathy characterized by severe demyelination and axonal loss in human, with both motor and sensory involvement. However, it is unclear whether FIG4 has cell autonomous roles in both motor neurons and Schwann cells, and how loss of FIG4/PtdIns(3,5)P2-mediated functions contribute to the pathogenesis of CMT4J. Here, we report that mice with conditional inactivation of Fig4 in motor neurons display neuronal and axonal degeneration. In contrast, conditional inactivation of Fig4 in Schwann cells causes demyelination and defects in autophagy-mediated degradation. Moreover, Fig4-regulated endolysosomal trafficking in Schwann cells is essential for myelin biogenesis during development and for proper regeneration/remyelination after injury. Our data suggest that impaired endolysosomal trafficking in both motor neurons and Schwann cells contributes to CMT4J neuropathy. PMID:25187576

  16. Loss of Fig4 in both Schwann cells and motor neurons contributes to CMT4J neuropathy.

    PubMed

    Vaccari, Ilaria; Carbone, Antonietta; Previtali, Stefano Carlo; Mironova, Yevgeniya A; Alberizzi, Valeria; Noseda, Roberta; Rivellini, Cristina; Bianchi, Francesca; Del Carro, Ubaldo; D'Antonio, Maurizio; Lenk, Guy M; Wrabetz, Lawrence; Giger, Roman J; Meisler, Miriam H; Bolino, Alessandra

    2015-01-15

    Mutations of FIG4 are responsible for Yunis-Varón syndrome, familial epilepsy with polymicrogyria, and Charcot-Marie-Tooth type 4J neuropathy (CMT4J). Although loss of the FIG4 phospholipid phosphatase consistently causes decreased PtdIns(3,5)P₂ levels, cell-specific sensitivity to partial loss of FIG4 function may differentiate FIG4-associated disorders. CMT4J is an autosomal recessive neuropathy characterized by severe demyelination and axonal loss in human, with both motor and sensory involvement. However, it is unclear whether FIG4 has cell autonomous roles in both motor neurons and Schwann cells, and how loss of FIG4/PtdIns(3,5)P₂-mediated functions contribute to the pathogenesis of CMT4J. Here, we report that mice with conditional inactivation of Fig4 in motor neurons display neuronal and axonal degeneration. In contrast, conditional inactivation of Fig4 in Schwann cells causes demyelination and defects in autophagy-mediated degradation. Moreover, Fig4-regulated endolysosomal trafficking in Schwann cells is essential for myelin biogenesis during development and for proper regeneration/remyelination after injury. Our data suggest that impaired endolysosomal trafficking in both motor neurons and Schwann cells contributes to CMT4J neuropathy. PMID:25187576

  17. Ficus religiosa L. figs--a potential herbal adjuvant to phenytoin for improved management of epilepsy and associated behavioral comorbidities.

    PubMed

    Singh, Paramdeep; Singh, Damanpreet; Goel, Rajesh Kumar

    2014-12-01

    Oxidative stress, together with mitochondrial dysfunction, has been reported to be involved in the pathogenesis of epileptogenesis and its associated comorbidities. Phytoflavonoids have shown numerous beneficial ameliorative effects on different neurological disorders by virtue of their antioxidant effect. The present study investigated the effect of flavonoid-rich ethyl acetate fraction of the crude fig extract of Ficus religiosa in combination with phenytoin on seizure severity, depressive behavior, and cognitive deficit in pentylenetetrazol (PTZ)-kindled mice. The flavonoid-rich ethyl acetate fraction of the crude fig extract was found to show significant antioxidant potential in various in vitro free radical scavenging assays. Combined treatment of this fraction (2.5, 5, and 10 mg/kg; i.p.) along with a subeffective dose of phenytoin (15 mg/kg; i.p.) in postkindled animals once daily for fifteen days showed a dose-dependent decrease in the seizure severity score, a decreased number of mistakes, increased step-down latency in passive shock avoidance paradigm, and decreased immobility time in the tail suspension test in comparison with the phenytoin only-treated group. Biochemical investigations of the brain tissue showed amelioration of thiobarbituric acid reactive substances (TBARS), reduced glutathione (GSH) levels, and reduced catalase and acetylcholinesterase (AChE) activities, thereby indicating suppression of oxidative stress. In conclusion, the results of the present study showed the protective effect of the flavonoid-rich fraction of F. religiosa along with a subeffective dose of phenytoin in PTZ-kindling-associated cognitive deficit and depressive behavior with complete suppression of seizures through reduction of oxidative stress, supporting the the need for clinical evaluation of the supplementation of phytoflavonoids along with antiepileptic drugs (AEDs) for management of epilepsy and its psychiatric and cognitive comorbidities. PMID:25461211

  18. Optical imaging of fast light-evoked fast neural activation in amphibian retina

    NASA Astrophysics Data System (ADS)

    Yao, Xin-Cheng; George, John S.

    2006-02-01

    High performance functional imaging is needed for dynamic measurements of neural processing in retina. Emerging techniques of visual prosthesis also require advanced methodology for reliable validation of electromagnetic stimulation of the retina. Imaging of fast intrinsic optical responses associated with neural activation promises a variety of technical advantages over traditional single and multi-channel electrophysiological techniques for these purposes, but the application of fast optical signals for neural imaging has been limited by low signal to noise ratio and high background light intensity. However, using optimized near infrared probe light and improved optical systems, we have improved the optical signals substantially, allowing single pass measurements. Fast photodiode measurements typically disclose dynamic transmitted light changes of whole retina at the level of 10 -4 dI/I, where dI is the dynamic optical change and I is the baseline light intensity. Using a fast high performance CCD, we imaged fast intrinsic optical responses from isolated retina activated by a visible light flash. Fast, high resolution imaging disclosed larger local optical responses, and showed evidence of multiple response components with both negative- and positive-going signals, on different timescales. Darkfield imaging techniques further enhanced the sensitivity of optical measurements. At single cell resolution, brightfield imaging disclosed maxima of optical responses ~5% dI/I, while darkfield imaging showed maxima of optical responses exceeding 10% dI/I. In comparison with simultaneous electrophysiological recording, optical imaging provided much better localized patterns of response over the activated area of the retina.

  19. Soft-tissues Image Processing: Comparison of Traditional Segmentation Methods with 2D active Contour Methods

    NASA Astrophysics Data System (ADS)

    Mikulka, J.; Gescheidtova, E.; Bartusek, K.

    2012-01-01

    The paper deals with modern methods of image processing, especially image segmentation, classification and evaluation of parameters. It focuses primarily on processing medical images of soft tissues obtained by magnetic resonance tomography (MR). It is easy to describe edges of the sought objects using segmented images. The edges found can be useful for further processing of monitored object such as calculating the perimeter, surface and volume evaluation or even three-dimensional shape reconstruction. The proposed solutions can be used for the classification of healthy/unhealthy tissues in MR or other imaging. Application examples of the proposed segmentation methods are shown. Research in the area of image segmentation focuses on methods based on solving partial differential equations. This is a modern method for image processing, often called the active contour method. It is of great advantage in the segmentation of real images degraded by noise with fuzzy edges and transitions between objects. In the paper, results of the segmentation of medical images by the active contour method are compared with results of the segmentation by other existing methods. Experimental applications which demonstrate the very good properties of the active contour method are given.

  20. Spectral ladar: towards active 3D multispectral imaging

    NASA Astrophysics Data System (ADS)

    Powers, Michael A.; Davis, Christopher C.

    2010-04-01

    In this paper we present our Spectral LADAR concept, an augmented implementation of traditional LADAR. This sensor uses a polychromatic source to obtain range-resolved 3D spectral images which are used to identify objects based on combined spatial and spectral features, resolving positions in three dimensions and up to hundreds of meters in distance. We report on a proof-of-concept Spectral LADAR demonstrator that generates spectral point clouds from static scenes. The demonstrator transmits nanosecond supercontinuum pulses generated in a photonic crystal fiber. Currently we use a rapidly tuned receiver with a high-speed InGaAs APD for 25 spectral bands with the future expectation of implementing a linear APD array spectrograph. Each spectral band is independently range resolved with multiple return pulse recognition. This is a critical feature, enabling simultaneous spectral and spatial unmixing of partially obscured objects when not achievable using image fusion of monochromatic LADAR and passive spectral imagers. This enables higher identification confidence in highly cluttered environments such as forested or urban areas (e.g. vehicles behind camouflage or foliage). These environments present challenges for situational awareness and robotic perception which can benefit from the unique attributes of Spectral LADAR. Results from this demonstrator unit are presented for scenes typical of military operations and characterize the operation of the device. The results are discussed here in the context of autonomous vehicle navigation and target recognition.

  1. Pigment Changes Associated with Application of Ethephon ((2-Chloroethyl)phosphonic Acid) to Fig (Ficus carica L.) Fruits

    PubMed Central

    Puech, Antoine A.; Rebeiz, Constantin A.; Crane, Julian C.

    1976-01-01

    The application of (2-chloroethyl)phosphonic acid (Ethephon) to `Mission' fig fruits (Ficus carica L.) during late period II of their development stimulated ripening and change in color from green to bluish black within 8 days. Chlorophylls a and b decreased rapidly within 4 days after Ethephon treatment, and degradation continued at a decreasing rate for an additional 4 days, at which time the fruits had attained their maximum diameter and were considered fully ripe. Levels of β-carotene, lutein, violaxanthin, and neoxanthin decreased in a pattern similar to that of chlorophylls a and b. The rates of β-carotene and lutein degradation were initially greater than those of the xanthophyll pigments. Degradation rates of the various carotenoids were comparable 4 to 8 days after treatment. There was no measurable anthocyanin synthesis during a 2- to 4-day period following Ethephon treatment. Beyond this lag phase, anthocyanin accumulation was linear, and the amount of pigment synthesized was a function of both light intensity and duration. Although Ethephon promoted the rate of anthocyanin accumulation, it did not increase the total amount of pigment synthesized in treated fruits. Etiolation of fruits from the time of Ethephon treatment until maturity stimulated an increase in growth and completely inhibited anthocyanin production in the skin. Ethephon-treated fruits which ripened while etiolated were larger in diameter and higher in both fresh and dry weights than nonetiolated controls. Images PMID:16659515

  2. Some Problems for Representations of Brain Organization Based on Activation in Functional Imaging

    ERIC Educational Resources Information Center

    Sidtis, John J.

    2007-01-01

    Functional brain imaging has overshadowed traditional lesion studies in becoming the dominant approach to the study of brain-behavior relationships. The proponents of functional imaging studies frequently argue that this approach provides an advantage over lesion studies by observing normal brain activity in vivo without the disruptive effects of…

  3. Signal extraction from movies of honeybee brain activity: the ImageBee plugin for KNIME

    PubMed Central

    2013-01-01

    Background In the antennal lobe, a dedicated olfactory center of the honeybee brain, odours are encoded as activity patterns of coding units, the so-called glomeruli. Optical imaging with calcium-sensitive dyes allows us to record these activity patterns and to gain insight into olfactory information processing in the brain. Method We introduce ImageBee, a plugin for the data analysis platform KNIME. ImageBee provides a variety of tools for processing optical imaging data. The main algorithm behind ImageBee is a matrix factorisation approach. Motivated by a data-specific, non-negative mixture model, the algorithm aims to select the generating extreme vectors of a convex cone that contains the data. It approximates the movie matrix by non-negative combinations of the extreme vectors. These correspond to pure glomerular signals that are not mixed with neighbour signals. Results Evaluation shows that the proposed algorithm can identify the relevant biological signals on imaging data from the honeybee AL, as well as it can recover implanted source signals from artificial data. Conclusions ImageBee enables automated data processing and visualisation for optical imaging data from the insect AL. The modular implementation for KNIME offers a flexible platform for data analysis projects, where modules can be rearranged or added depending on the particular application. Availability ImageBee can be installed via the KNIME update service. Installation instructions are available at http://tech.knime.org/imagebee-analysing-imaging-data-from-the-honeybee-brain. PMID:24564238

  4. Novel assay for direct fluorescent imaging of sialidase activity

    NASA Astrophysics Data System (ADS)

    Tomin, A.; Shkandina, T.; Bilyy, R.

    2011-07-01

    Here we describe a novel approach to sialidase activity estimation. Sialidases (EC 3.2.1.18, exo-α-sialidases), also known as neuraminidases, are the group of enzymes, which hydrolyze the glycoside bound between terminal sialic acid and subsequent carbohydrate residue in glycoproteins and glycolipids. Sialic acids are the group of monosaccharides with acidic properties, since they are acetylated or glycolylated derivates of neuraminic acid. Flu and some other viruses use neuraminidase activity to infect host cells. The level of sialylation was shown to be tightly connected with tumor cell invasiveness and metastatic potential, sialylation level also determines the clearance of aged or virus-infected cells. Thus, detection of sialidase activity is of primary importance for clinical diagnostics as well as life science research. The authors developed the assay for both visualization and estimation of sialidase activity in living cells. Previously known methods for sialidase activity detection required destruction of cellular material, or were low-sensitive, or provided no information on the activity localization in certain intracellular compartment. To overcome these problems, a fluorogenic neuraminidase substrate, 4-MUNA was utilized, and the method for detection of neuraminidase activity using fluorescent microscopy was proposed, it provided a high signal level and information on cellular localization of the studied enzyme. By using this approach the increase of sialidase activity on apoptotic cells was demonstrated in comparison to viable and primary necrotic cells.

  5. Treatments with gras compounds to keep fig fruit (Ficus carica L.) quality during cold storage.

    PubMed

    Venditti, T; Molinu, M G; Dore, A; D'Hallewin, G; Fiori, P; Tedde, M; Agabbio, M

    2005-01-01

    The trade of fresh fig fruit is restricted by its high perishability and numerous attempts have been done to extend the postharvest life. The main difficulties can be found in the fast ripening and the easiness of pathogen spread. Although the ripening can be slowed by low storage temperatures (close to 0 degrees C) the control of pathogens remains still unsolved since no pesticide treatments are allowed. Generally Recognized As Save Compounds (G.R.A.S.) are possible candidates to fulfil this void. Sodium carbonate (SC) solutions (0.5, 1, 2 and 3%) and acetic acid (AAC) vapours (25, 50 and 100 ppm) have been used as postharvest treatments to control Botrytis cinerea on black (Craxiou de Porcu) and white (Rampelina) fig varieties. Fruit was subsequently stored at 2 or 8 degrees C and 90% relative humidity for two weeks. At the end of the experiment decay, weight loss, pH, acidity, total soluble solids and visual assessment were performed. SC treatment at 1% reduced significantly the decay while, lower and higher concentrations did not. Between the two studied varieties the lowest decay percentage (9.8%) was found for the Craxiou de Porcu. Using AAC a good efficacy was achieved only with 100 ppm, this treatment decrease to 2.4% the incidence of decay irrespective to storage temperature. Lower concentrations were lesser effective and the efficacy was strictly dependent on the storage temperature, being higher at 2 degrees C. No treatment damages were observed following SC or AAC applications. Regarding fruit weight loss all treatments did not affect this parameter that was 10.1% and 16.9% at 2 and 8 degrees C, respectively. Chemical analyses performed at the end of the storage period did not evidenced differences among the treatments and slight ones if compared to initial values. Visual score of the fruit at the end of storage evidenced a better keeping quality for Craxiou de Porcu especially when stored at 2 degrees C. Both G.R.A.S. compounds are promising, but in

  6. Real-time functional near-infrared imager and imaging of human brain activity

    NASA Astrophysics Data System (ADS)

    Luo, Qingming; Zeng, Shaoqun; Gong, Hui; Chen, Weiguo; Zhang, Zhi; Chance, Britton

    1999-02-01

    A real time functional near infrared imager (fNIRI) was introduced. The imager was controlled by a computer and the signals from the detectors were converted and processed in real time. A user-friendly software was programmed with Visual C++ language. Relative changes of oxy - Hb, Hb, and total blood concentration in 16 channels and the corresponding images can be displayed in real time on the computer. The imager was used as a real time monitor in psychological tests to record the response of the frontal cortex of human subjects. In mental work and pattern recognition tests, we recorded oxygen consumption and blood flow changes of volunteers' frontal cortex. The psychological results showed that the lower part of the left frontal gyres had intensive relation to pattern recognition and has definite boundaries. However, the mental work involved more zones of the frontal gyres and may be a complex conceptual model. The results also suggested that the human brain has an precise and complicated adjustability. The oxygen supplement in the stimulated area increased as the neuron stimulation.

  7. Validation of an active transponder for KOMPSAT-5 SAR image calibration

    NASA Astrophysics Data System (ADS)

    Park, Durk Jong; Yeom, Kyung Whan; Ahn, Sang Il; Lim, Hyo Suk

    2014-10-01

    This paper describes the development and validation of a transportable active transponder designed for the image calibration of Korea Multi-Purpose Satellite-5 (KOMPSAT-5) with a synthetic aperture radar (SAR). Ground targets are essential in SAR image calibration. The environment for the deployment of ground targets for SAR image calibration should provide uniformity and minimum interference. The Amazon or deserts are regarded as desirable environments. However, such environments for SAR image calibration are difficult to find in Korea. Thus, it will be advantageous to have an active transponder whose performance will not be severely limited by the absence of such uniform environment. We have therefore developed an active transponder which has an adjustable internal delay and into which the orbit data of an arbitrary satellite can be loaded. The stored obit data with the aid of an internal global positioning system (GPS) receiver and gyroscope enables the active transponder to point to a selected satellite. In addition, a virtual deployment of the active transponder is possible due to its adjustable internal delay. Thus, the developed active transponder can be deployed at any place without environmental constraint. The performance of the developed active transponder is validated using the satellite TerraSAR-X, which is already in operation. The test results show that the active transponder is successfully compliant with the requirements for KOMPSAT-5 image calibration.

  8. Living on the edge: Fig tree phenology at the northern range limit of monoecious Ficus in China

    NASA Astrophysics Data System (ADS)

    Zhang, Lu-Shui; Compton, Stephen G.; Xiao, Hui; Lu, Qian; Chen, Yan

    2014-05-01

    Fig trees (Ficus) are a species-rich group of mainly tropical and subtropical plants that are of ecological importance because of the large numbers of vertebrates that utilise their figs for food. Factors limiting their distributions to warmer regions are still poorly understood, but are likely to include factors linked to their specialised pollination biology, because each Ficus species is dependent on one or a small number of host-specific fig wasps (Agaonidae) for pollination. Adult fig wasps are short-lived, but some species are capable of dispersing extremely long distances to pollinate their hosts. Close to its northern range limit we investigated the phenology of Ficus virens, the monoecious fig tree that reaches furthest north in China. Relatively few trees produced any figs, and very few retained figs throughout the winter. Despite this, new crops produced in spring were pollinated, with seasonally migrant pollinators from plants growing further south the most likely pollen vectors. An inability to initiate new crops at low temperatures may limit the distribution of monoecious fig trees to warmer areas.

  9. 75 FR 6344 - Notice of Availability of Pest Risk Analyses for Importation of Fresh Figs, Pomegranates, and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-09

    ... of Fresh Figs, Pomegranates, and Baby Kiwi from Chile into the United States AGENCY: Animal and Plant... prepared two pest risk analyses, one with respect to fresh figs and pomegranates grown in Chile and one with respect to fresh baby kiwi fruit grown in Chile. The analyses evaluate the risks associated...

  10. How to be a dioecious fig: Chemical mimicry between sexes matters only when both sexes flower synchronously.

    PubMed

    Hossaert-McKey, M; Proffit, M; Soler, C C L; Chen, C; Bessière, J-M; Schatz, B; Borges, R M

    2016-01-01

    In nursery pollination mutualisms, which are usually obligate interactions, olfactory attraction of pollinators by floral volatile organic compounds (VOCs) is the main step in guaranteeing partner encounter. However, mechanisms ensuring the evolutionary stability of dioecious fig-pollinator mutualisms, in which female fig trees engage in pollination by deceit resulting in zero reproductive success of pollinators that visit them, are poorly understood. In dioecious figs, individuals of each sex should be selected to produce odours that their pollinating wasps cannot distinguish, especially since pollinators have usually only one choice of a nursery during their lifetime. To test the hypothesis of intersexual chemical mimicry, VOCs emitted by pollen-receptive figs of seven dioecious species were compared using headspace collection and gas chromatography-mass spectrometry analysis. First, fig-flower scents varied significantly among species, allowing host-species recognition. Second, in species in which male and female figs are synchronous, intersexual VOC variation was not significant. However, in species where figs of both sexes flower asynchronously, intersexual variation of VOCs was detectable. Finally, with one exception, there was no sexual dimorphism in scent quantity. We show that there are two ways to use scent to be a dioecious fig based on differences in flowering synchrony between the sexes. PMID:26888579

  11. Natural enemies managing the invasion of the Fig whitefly, Singhiella simplex (Hemiptera: Aleyrodidae), infesting a Ficus benjamina hedge

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The fig whitefly, Singhiella simplex (Singh) is a recent invasive species that has become a major pest in Florida feeding on Ficus shrubs and trees. A pilot study was conducted on a weeping fig, Ficus benjamina shrub hedge to determine the efficacy and compatibility of a biopesticide (PFR 97™=Isaria...

  12. Histochemical studies on genetical control of hormonal enzyme inducibility in the mouse. I. Non-specific esterase activity and regional histology of the epididymis.

    PubMed Central

    Blecher, S R; Kirkeby, S

    1978-01-01

    As a base line for future cell genetical studies the authors record the distribution of non-specific esterase reaction in the various histologically distinguishable cell types of the mouse epididymis. The findings are correlated with previous descriptions of the lobar structure of the organ. Assuming the sequence of lobes of the head to be as implied in these classical descriptions, the esterase activity of the epithelial cells gradates between strong to weak several times along the length of the epididymal duct. The relationship of the lobes to each other, as seen in transverse sections, is described. Methodological studies using different fixatives indicate that apparent similarity of esterase reaction at different sites may camouflage an underlying difference in the nature of the esterases at these sites. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 PMID:564339

  13. Imaging the coordination of multiple signaling activities in living cells

    PubMed Central

    Welch, Christopher M.; Elliott, Hunter; Danuser, Gaudenz; Hahn, Klaus M.

    2013-01-01

    Preface Cellular signal transduction occurs in complex and redundant interaction networks that are best examined at the level of single cells by simultaneously monitoring the activation dynamics of multiple components. Recent advances in biosensor technology have made it possible to visualize and quantify the activation of multiple network nodes in the same living cell. The precision and scope of this approach has been greatly extended by novel computational approaches to determine the relationships between different networks, studied in separate cells. PMID:22016058

  14. Mating system and sex ratios of a pollinating fig wasp with dispersing males.

    PubMed Central

    Greeff, Jaco M

    2002-01-01

    Recent studies have used sex ratios to quantify the mating systems of organisms, the argument behind it being that more female-biased sex ratios are an indication of higher local mate competition, which goes hand-in-hand with higher levels of inbreeding. Although qualitative tests of the effects of mating systems on sex ratios abound, there is a dearth of studies that quantify both the mating system and the sex ratio. I use a colour dimorphism with a simple Mendelian inheritance to quantify the mating system of an unusual fig-pollinating wasp in which males disperse to obtain matings on non-natal mating patches. In qualitative agreement with initial expectations, the sex ratios of single foundresses are found to be higher than those of regular species. However, by quantifying the mating system, it is shown that the initial expectation is incorrect and this species' sex ratio is a poor predictor of its mating system (it underestimates the frequency of sib-mating). The species has a very high variance in sex ratio suggesting that excess males can simply avoid local mate competition (and hence a lowered fitness to their mother) by dispersing to other patches. PMID:12495498

  15. Antioxidant and hepatoprotective properties of dried fig against oxidative stress and hepatotoxicity in rats.

    PubMed

    Turan, Abdullah; Celik, Ismail

    2016-10-01

    The aim of this study was to investigate the hepatoprotective effect and antioxidant role of dried fig (DF) (Ficus carica L.) against ethanol-induced oxidative stress. Experiment was designed as normal Control, 20% ethanol, 10% DF and 10% DF+20% ethanol groups. The hepatoprotective and antioxidant role of the dried DF supplementation feed against ethanol induced oxidatif stress were evaluated by liver histopathological changes, measuring liver damage serum enzymes (LDSE), antioxidant defense system (ADS) and malondialdehyde (MDA) content in various tissues of rats following the exposure of experimental for 50days. The biochemical analysis showed a considerable increase the LDSE in the ethanol group as compared to that of control group whereas, decreased in 10% DF+20% ethanol group as compared to that of ethanol group. In addition, the DF supplementation diet restored the ethanol-induced MDA and ADS towards to control. The hepatoprotection of DF is further substantiated by the almost normal histologic findings of liver in 10% DF+20% ethanol group against degenerative changes in ethanol group. The results indicated that the DF could be as important as diet-derived antioxidants and antihepatotoxicity in preventing oxidative damage in the tissues by inhibiting the production of ethanol-induced free radicals and hepatotoxicity in rats. PMID:27268385

  16. Actinoalloteichus nanshanensis sp. nov., isolated from the rhizosphere of a fig tree (Ficus religiosa).

    PubMed

    Xiang, Wensheng; Liu, Chongxi; Wang, Xiangjing; Du, Jing; Xi, Lijun; Huang, Ying

    2011-05-01

    A Gram-positive, aerobic actinomycete, designated strain NEAU 119(T), was isolated from the rhizosphere of a fig tree and was characterized using a polyphasic approach. The isolate formed branching, non-fragmenting vegetative hyphae and produced black pigment on yeast extract/malt extract (ISP medium 2). The G+C content of the DNA was 76.6 mol%. The organism had chemotaxonomic characteristics typical of the genus Actinoalloteichus and was closely related to the type strains of Actinoalloteichus cyanogriseus, Actinoalloteichus spitiensis and Actinoalloteichus hymeniacidonis, currently the only three recognized species of the genus Actinoalloteichus, sharing 16S rRNA gene similarities of 96.4, 96.6 and 98.1 %, respectively. However, the results of DNA-DNA hybridization studies demonstrated that the novel strain showed only 46.8 % relatedness with the type strain of A. hymeniacidonis. In addition, a set of phenotypic characteristics also readily distinguished strain NEAU 119(T) from the type strains of recognized species of the genus Actinoalloteichus. According to the above data, it is proposed that strain NEAU 119(T) represents a novel species, Actinoalloteichus nanshanensis sp. nov. The type strain of Actinoalloteichus nanshanensis is NEAU 119(T) ( = CGMCC 4.5714(T) = NBRC 106685(T)). PMID:20562245

  17. Emission Line Science in the Faint Infrared Grism Survey (FIGS) Sample

    NASA Astrophysics Data System (ADS)

    Smith, Mark David; Malhotra, Sangeeta; Pharo, John; Rhoads, James E.; FIGS Team

    2016-01-01

    Emission lines can reveal a bounty of information about the processes occurring within a galaxy. Physical properties such as star formation rate and metallicity can be determined from ratios of emission line fluxes. The study of emission line galaxies (ELGs) through cosmic time gives insight into the processes by which galaxies evolve. Extreme emission line galaxies (EELGs), typified by strong nebular emission lines which dominate their spectra, are of interest because they are well known to be galaxies undergoing periods of intense star formation. Slitless grism spectroscopy offers a significant advantage to the study of ELGs and EELGs, allowing for measurement of the spectra of a large number of galaxies within a field. This allows for detection of ELGs and EELGs with few selection biases. Optical follow-up of FIGS-selected sources allows for analysis of star formation rate (SFR) through H-alpha measurements over the redshift range 0.3

  18. Efficient thermal image segmentation through integration of nonlinear enhancement with unsupervised active contour model

    NASA Astrophysics Data System (ADS)

    Albalooshi, Fatema A.; Krieger, Evan; Sidike, Paheding; Asari, Vijayan K.

    2015-03-01

    Thermal images are exploited in many areas of pattern recognition applications. Infrared thermal image segmentation can be used for object detection by extracting regions of abnormal temperatures. However, the lack of texture and color information, low signal-to-noise ratio, and blurring effect of thermal images make segmenting infrared heat patterns a challenging task. Furthermore, many segmentation methods that are used in visible imagery may not be suitable for segmenting thermal imagery mainly due to their dissimilar intensity distributions. Thus, a new method is proposed to improve the performance of image segmentation in thermal imagery. The proposed scheme efficiently utilizes nonlinear intensity enhancement technique and Unsupervised Active Contour Models (UACM). The nonlinear intensity enhancement improves visual quality by combining dynamic range compression and contrast enhancement, while the UACM incorporates active contour evolutional function and neural networks. The algorithm is tested on segmenting different objects in thermal images and it is observed that the nonlinear enhancement has significantly improved the segmentation performance.

  19. Imaging fast electrical activity in the brain with electrical impedance tomography

    PubMed Central

    Aristovich, Kirill Y.; Packham, Brett C.; Koo, Hwan; Santos, Gustavo Sato dos; McEvoy, Andy; Holder, David S.

    2016-01-01

    Imaging of neuronal depolarization in the brain is a major goal in neuroscience, but no technique currently exists that could image neural activity over milliseconds throughout the whole brain. Electrical impedance tomography (EIT) is an emerging medical imaging technique which can produce tomographic images of impedance changes with non-invasive surface electrodes. We report EIT imaging of impedance changes in rat somatosensory cerebral cortex with a resolution of 2 ms and < 200 μm during evoked potentials using epicortical arrays with 30 electrodes. Images were validated with local field potential recordings and current source-sink density analysis. Our results demonstrate that EIT can image neural activity in a volume 7 × 5 × 2 mm in somatosensory cerebral cortex with reduced invasiveness, greater resolution and imaging volume than other methods. Modeling indicates similar resolutions are feasible throughout the entire brain so this technique, uniquely, has the potential to image functional connectivity of cortical and subcortical structures. PMID:26348559

  20. A Partition-Based Active Contour Model Incorporating Local Information for Image Segmentation

    PubMed Central

    Wu, Jiaji; Jiao, Licheng; Gong, Maoguo

    2014-01-01

    Active contour models are always designed on the assumption that images are approximated by regions with piecewise-constant intensities. This assumption, however, cannot be satisfied when describing intensity inhomogeneous images which frequently occur in real world images and induced considerable difficulties in image segmentation. A milder assumption that the image is statistically homogeneous within different local regions may better suit real world images. By taking local image information into consideration, an enhanced active contour model is proposed to overcome difficulties caused by intensity inhomogeneity. In addition, according to curve evolution theory, only the region near contour boundaries is supposed to be evolved in each iteration. We try to detect the regions near contour boundaries adaptively for satisfying the requirement of curve evolution theory. In the proposed method, pixels within a selected region near contour boundaries have the opportunity to be updated in each iteration, which enables the contour to be evolved gradually. Experimental results on synthetic and real world images demonstrate the advantages of the proposed model when dealing with intensity inhomogeneity images. PMID:25147868

  1. Brain MRI Tumor Detection using Active Contour Model and Local Image Fitting Energy

    NASA Astrophysics Data System (ADS)

    Nabizadeh, Nooshin; John, Nigel

    2014-03-01

    Automatic abnormality detection in Magnetic Resonance Imaging (MRI) is an important issue in many diagnostic and therapeutic applications. Here an automatic brain tumor detection method is introduced that uses T1-weighted images and K. Zhang et. al.'s active contour model driven by local image fitting (LIF) energy. Local image fitting energy obtains the local image information, which enables the algorithm to segment images with intensity inhomogeneities. Advantage of this method is that the LIF energy functional has less computational complexity than the local binary fitting (LBF) energy functional; moreover, it maintains the sub-pixel accuracy and boundary regularization properties. In Zhang's algorithm, a new level set method based on Gaussian filtering is used to implement the variational formulation, which is not only vigorous to prevent the energy functional from being trapped into local minimum, but also effective in keeping the level set function regular. Experiments show that the proposed method achieves high accuracy brain tumor segmentation results.

  2. Multiple Active Contours Guided by Differential Evolution for Medical Image Segmentation

    PubMed Central

    Cruz-Aceves, I.; Avina-Cervantes, J. G.; Lopez-Hernandez, J. M.; Rostro-Gonzalez, H.; Garcia-Capulin, C. H.; Torres-Cisneros, M.; Guzman-Cabrera, R.

    2013-01-01

    This paper presents a new image segmentation method based on multiple active contours guided by differential evolution, called MACDE. The segmentation method uses differential evolution over a polar coordinate system to increase the exploration and exploitation capabilities regarding the classical active contour model. To evaluate the performance of the proposed method, a set of synthetic images with complex objects, Gaussian noise, and deep concavities is introduced. Subsequently, MACDE is applied on datasets of sequential computed tomography and magnetic resonance images which contain the human heart and the human left ventricle, respectively. Finally, to obtain a quantitative and qualitative evaluation of the medical image segmentations compared to regions outlined by experts, a set of distance and similarity metrics has been adopted. According to the experimental results, MACDE outperforms the classical active contour model and the interactive Tseng method in terms of efficiency and robustness for obtaining the optimal control points and attains a high accuracy segmentation. PMID:23983809

  3. Reconstructing liver shape and position from MR image slices using an active shape model

    NASA Astrophysics Data System (ADS)

    Fenchel, Matthias; Thesen, Stefan; Schilling, Andreas

    2008-03-01

    We present an algorithm for fully automatic reconstruction of 3D position, orientation and shape of the human liver from a sparsely covering set of n 2D MR slice images. Reconstructing the shape of an organ from slice images can be used for scan planning, for surgical planning or other purposes where 3D anatomical knowledge has to be inferred from sparse slices. The algorithm is based on adapting an active shape model of the liver surface to a given set of slice images. The active shape model is created from a training set of liver segmentations from a group of volunteers. The training set is set up with semi-manual segmentations of T1-weighted volumetric MR images. Searching for the optimal shape model that best fits to the image data is done by maximizing a similarity measure based on local appearance at the surface. Two different algorithms for the active shape model search are proposed and compared: both algorithms seek to maximize the a-posteriori probability of the grey level appearance around the surface while constraining the surface to the space of valid shapes. The first algorithm works by using grey value profile statistics in normal direction. The second algorithm uses average and variance images to calculate the local surface appearance on the fly. Both algorithms are validated by fitting the active shape model to abdominal 2D slice images and comparing the shapes, which have been reconstructed, to the manual segmentations and to the results of active shape model searches from 3D image data. The results turn out to be promising and competitive to active shape model segmentations from 3D data.

  4. Molecular Imaging of Microglial Activation in Amyotrophic Lateral Sclerosis

    PubMed Central

    Corcia, Philippe; Tauber, Clovis; Vercoullie, Johnnie; Arlicot, Nicolas; Prunier, Caroline; Praline, Julien; Nicolas, Guillaume; Venel, Yann; Hommet, Caroline; Baulieu, Jean-Louis; Cottier, Jean-Philippe; Roussel, Catherine; Kassiou, Mickael; Guilloteau, Denis; Ribeiro, Maria-Joao

    2012-01-01

    There is growing evidence of activated microglia and inflammatory processes in the cerebral cortex in amyotrophic lateral sclerosis (ALS). Activated microglia is characterized by increased expression of the 18 kDa translocator protein (TSPO) in the brain and may be a useful biomarker of inflammation. In this study, we evaluated neuroinflammation in ALS patients using a radioligand of TSPO, 18F-DPA-714. Ten patients with probable or definite ALS (all right-handed, without dementia, and untreated by riluzole or other medication that might bias the binding on the TSPO), were enrolled prospectively and eight healthy controls matched for age underwent a PET study. Comparison of the distribution volume ratios between both groups were performed using a Mann-Whitney’s test. Significant increase of distribution of volume ratios values corresponding to microglial activation was found in the ALS sample in primary motor, supplementary motor and temporal cortex (p = 0.009, p = 0.001 and p = 0.004, respectively). These results suggested that the cortical uptake of 18F-DPA-714 was increased in ALS patients during the “time of diagnosis” phase of the disease. This finding might improve our understanding of the pathophysiology of ALS and might be a surrogate marker of efficacy of treatment on microglial activation. PMID:23300829

  5. Images and Influences in the Promotion of Physical Activity

    ERIC Educational Resources Information Center

    Overdorf, Virginia

    2005-01-01

    This article presents the author's presentation on the 13th Delphine Hanna Commemorative Lecture in 2004. The presentation examines some of the problems and issues that must be addressed in order to promote physical activity in the academy and beyond. While there is no all embracing prescription, the author hopes to offer some suggestions that…

  6. Optical imaging of the prefrontal activity in joint attention experience

    PubMed Central

    Qiu, Lina; Zhang, Xiao; Li, Jun

    2015-01-01

    Functional near-infrared spectroscopy (fNIRS) was used to measure the prefrontal activity in joint attention experience. 16 healthy adults participated in the experiment in which 42 optical channels were fixed over the anterior prefrontal cortex (aPFC), dorsolateral prefrontal cortex (DLPFC), inferior frontal gyrus (IFG) and a small anterior portion of the superior temporal gyrus (STG). Video stimuli were used to engender joint or non-joint attention experience in observers. Cortical hemodynamic response and functional connectivity were measured and averaged across all subjects for each stimulus condition. Our data showed the activation in joint attention located in the aPFC and DLPFC bilaterally, but dominantly in the left hemisphere. This observation, together with the previous findings on infants and children, provides a clear developmental scenario on the prefrontal activation associated with joint attention process. In the case of non-joint attention condition, only a small region of the right DLPFC was activated. Functional connectivity was observed to be enhanced, but differently in joint and non-joint attention condition. PMID:26417513

  7. Distribution of nuclear mitochondrial pseudogenes in three pollinator fig wasps associated with Ficus pumila

    NASA Astrophysics Data System (ADS)

    Chen, Yan; Liu, Min; Compton, Stephen G.; Chen, Xiao-Yong

    2014-05-01

    Nuclear mitochondrial pseudogenes (NUMTs) are nuclear sequences transferred from mitochondrial genomes. Although widespread, their distribution patterns among populations or closely related species are rarely documented. We amplified and sequenced the mitochondrial cytochrome b (Cytb) gene to check for NUMTs in three fig wasp species that pollinate Ficus pumila (Wiebesia sp. 1, 2 and 3) in Southeastern China using direct and cloned sequencing. Unambiguous sequences (332) of 487 bp in length belonging to 33 haplotypes were found by direct sequencing. Their distribution was highly concordant with those of cytochrome c oxidase subunit I (COI). Obvious signs of co-amplification of NUMTs were indicated by their uneven distribution. NUMTs were observed in all individuals of 12 populations of Wiebesia sp. 3, and 13 individuals of three northern populations of Wiebesia sp. 1. Sequencing clones of potential co-amplification products confirmed that they were NUMTs. These NUMTs either clustered as NUMT clades basal to mtDNA Cytb clades (basal NUMTs), or together with Cytb haplotypes. Basal NUMTs had either stop codons or frame-shifting mutations resulting from deletion of a 106 bp fragment. In addition, no third codon or synonymous substitutions were detected within each NUMT clade. The phylogenetic tree indicated that basal NUMTs had been inserted into nuclei before divergence of the three species. No significant pairwise differences were detected in their ratios of third codon substitutions, suggesting that these NUMTs originated from one transfer event, with duplication in the nuclear genome resulting in the coexistence of the 381 bp copy. No significant substitution differences were detected between Cytb haplotypes and NUMTs that clustered with Cytb haplotypes. However, these NUMTs coexisted with Cytb haplotypes in multiple populations, suggesting that these NUMT haplotypes were recently inserted into the nuclear genome. Both basal and recently inserted NUMTs were rare

  8. Three-dimensional imaging simulation of active laser detection based on DLOS method

    NASA Astrophysics Data System (ADS)

    Zhang, Chuanxin; Zhou, Honghe; Chen, Xiang; Yuan, Yuan; Shuai, Yong; Tan, Heping

    2016-07-01

    The technology of active laser detection is widely used in many different fields nowadays. With the development of computer technology, programmable software simulation can provide reference for the design of active laser detection. The characteristics of the active laser detecting systems also can be judged more visual. Based on the features of the active laser detection, an improved method of radiative transfer calculation (Double Line Of Sight) was developed, and the simulation models of complete active laser detecting imaging were founded. Compared with the results calculated by the Monte Carlo method, the correctness of the improved method was verified. The results of active laser detecting imaging of complex three-dimensional targets in different atmospheric scenes were compared. The influence of different atmospheric dielectric property were analyzed, which provides effective reference for the design of active laser detection.

  9. How to be a dioecious fig: Chemical mimicry between sexes matters only when both sexes flower synchronously

    PubMed Central

    Hossaert-McKey, M.; Proffit, M.; Soler, C. C. L.; Chen, C.; Bessière, J.-M.; Schatz, B.; Borges, R. M.

    2016-01-01

    In nursery pollination mutualisms, which are usually obligate interactions, olfactory attraction of pollinators by floral volatile organic compounds (VOCs) is the main step in guaranteeing partner encounter. However, mechanisms ensuring the evolutionary stability of dioecious fig–pollinator mutualisms, in which female fig trees engage in pollination by deceit resulting in zero reproductive success of pollinators that visit them, are poorly understood. In dioecious figs, individuals of each sex should be selected to produce odours that their pollinating wasps cannot distinguish, especially since pollinators have usually only one choice of a nursery during their lifetime. To test the hypothesis of intersexual chemical mimicry, VOCs emitted by pollen-receptive figs of seven dioecious species were compared using headspace collection and gas chromatography-mass spectrometry analysis. First, fig-flower scents varied significantly among species, allowing host-species recognition. Second, in species in which male and female figs are synchronous, intersexual VOC variation was not significant. However, in species where figs of both sexes flower asynchronously, intersexual variation of VOCs was detectable. Finally, with one exception, there was no sexual dimorphism in scent quantity. We show that there are two ways to use scent to be a dioecious fig based on differences in flowering synchrony between the sexes. PMID:26888579

  10. Insect responses to host plant provision beyond natural boundaries: latitudinal and altitudinal variation in a Chinese fig wasp community

    PubMed Central

    Wang, Rong; Compton, Stephen G; Quinnell, Rupert J; Peng, Yan-Qiong; Barwell, Louise; Chen, Yan

    2015-01-01

    Many plants are grown outside their natural ranges. Plantings adjacent to native ranges provide an opportunity to monitor community assembly among associated insects and their parasitoids in novel environments, to determine whether gradients in species richness emerge and to examine their consequences for host plant reproductive success. We recorded the fig wasps (Chalcidoidea) associated with a single plant resource (ovules of Ficus microcarpa) along a 1200 km transect in southwest China that extended for 1000 km beyond the tree's natural northern range margin. The fig wasps included the tree's agaonid pollinator and other species that feed on the ovules or are their parasitoids. Phytophagous fig wasps (12 species) were more numerous than parasitoids (nine species). The proportion of figs occupied by fig wasps declined with increasing latitude, as did the proportion of utilized ovules in occupied figs. Species richness, diversity, and abundance of fig wasps also significantly changed along both latitudinal and altitudinal gradients. Parasitoids declined more steeply with latitude than phytophages. Seed production declined beyond the natural northern range margin, and at high elevation, because pollinator fig wasps became rare or absent. This suggests that pollinator climatic tolerances helped limit the tree's natural distribution, although competition with another species may have excluded pollinators at the highest altitude site. Isolation by distance may prevent colonization of northern sites by some fig wasps and act in combination with direct and host-mediated climatic effects to generate gradients in community composition, with parasitoids inherently more sensitive because of declines in the abundance of potential hosts. PMID:26380693

  11. Intracellular localization of mevalonate-activating enzymes in plant cells

    PubMed Central

    Rogers, L. J.; Shah, S. P. J.; Goodwin, T. W.

    1966-01-01

    Mevalonate-activating enzymes are shown to be present in the chloroplasts of French-bean leaves. The chloroplast membrane is impermeable to mevalonic acid. Mevalonate-activating enzymes also appear to be found outside the chloroplast. These results support the view that terpenoid biosynthesis in the plant cell is controlled by a combination of enzyme segregation and specific membrane permeability. ImagesFig. 1.Fig. 2. PMID:5947149

  12. How to Detect Amygdala Activity with Magnetoencephalography using Source Imaging

    PubMed Central

    Balderston, Nicholas L.; Schultz, Douglas H.; Baillet, Sylvain; Helmstetter, Fred J.

    2013-01-01

    , there have been recent advances in the methods used to localize the neural sources of the MEG signal9-11. By collecting high-resolution MRI images of the subject's brain, it is possible to create a source model based on individual neural anatomy. Using this model to "image" the sources of the MEG signal, it is possible to recover signal from deep subcortical structures, like the amygdala and the hippocampus*. PMID:23770774

  13. Non-Invasive Imaging of Neuroanatomical Structures and Neural Activation with High-Resolution MRI

    PubMed Central

    Herberholz, Jens; Mishra, Subrata H.; Uma, Divya; Germann, Markus W.; Edwards, Donald H.; Potter, Kimberlee

    2011-01-01

    Several years ago, manganese-enhanced magnetic resonance imaging (MEMRI) was introduced as a new powerful tool to image active brain areas and to identify neural connections in living, non-human animals. Primarily restricted to studies in rodents and later adapted for bird species, MEMRI has recently been discovered as a useful technique for neuroimaging of invertebrate animals. Using crayfish as a model system, we highlight the advantages of MEMRI over conventional techniques for imaging of small nervous systems. MEMRI can be applied to image invertebrate nervous systems at relatively high spatial resolution, and permits identification of stimulus-evoked neural activation non-invasively. Since the selection of specific imaging parameters is critical for successful in vivo micro-imaging, we present an overview of different experimental conditions that are best suited for invertebrates. We also compare the effects of hardware and software specifications on image quality, and provide detailed descriptions of the steps necessary to prepare animals for successful imaging sessions. Careful consideration of hardware, software, experiments, and specimen preparation will promote a better understanding of this novel technique and facilitate future MEMRI studies in other laboratories. PMID:21503138

  14. Abnormal fusiform activation during emotional-face encoding assessed with functional magnetic resonance imaging.

    PubMed

    Adleman, Nancy E; Kayser, Reilly R; Olsavsky, Aviva K; Bones, Brian L; Muhrer, Eli J; Fromm, Stephen J; Pine, Daniel S; Zarate, Carlos; Leibenluft, Ellen; Brotman, Melissa A

    2013-05-30

    This functional magnetic resonance imaging study shows that children and adults with bipolar disorder (BD), compared with healthy subjects, exhibit impaired memory for emotional faces and abnormal fusiform activation during encoding. Fusiform activation abnormalities in BD were correlated with mania severity and may therefore represent a trait and state BD biomarker. PMID:23541333

  15. Final Report: Imaging of Buried Nanoscale Optically Active Materials

    SciTech Connect

    Appelbaum, Ian

    2011-07-05

    This is a final report covering work done at University of Maryland to develop a Ballistic Electron Emission Luminescence (BEEL) microscope. This technique was intended to examine the carrier transport and photon emission in deeply buried optically-active layers and thereby provide a means for materials science to unmask the detailed consequences of experimentally controllable growth parameters, such as quantum dot size, statistics and orientation, and defect density and charge recombination pathways.

  16. Thermal imaging of Erta 'Ale active lava lake (Ethiopia)

    NASA Astrophysics Data System (ADS)

    Spampinato, L.; Oppenheimer, C.; Calvari, S.; Cannata, A.; Montalto, P.

    2009-04-01

    Active lava lakes represent the uppermost portion of a volume of convective magma exposed to the atmosphere, and provide open windows on magma dynamics within shallow reservoirs. Erta ‘Ale volcano located within the Danakil Depression in Ethiopia, hosts one of the few permanent convecting lava lakes, active at least since the last century. We report here the main features of Erta ‘Ale lake surface investigated using a hand-held infrared thermal camera between 11 and 12 November 2006. In both days, the lake surface was mainly characterized by efficient magma circulation reflecting in the formation of well-marked incandescent cracks and wide crust plates. These crossed the lake from the upwelling to the downwelling margin with mean speeds ranging between 0.01 and 0.15 m s-1. Hot spots opened eventually in the middle of crust plates and/or along cracks. These produced explosive activity lasting commonly between ~10 and 200 sec. Apparent temperatures at cracks ranged between ~700 and 1070˚C, and between ~300 and 500˚C at crust plates. Radiant power output of the lake varied between ~45 and 76 MW according to the superficial activity and continuous resurfacing of the lake. Time series analysis of the radiant power output data reveals cyclicity with a period of ~10 min. The combination of visual and thermal observations with apparent mean temperatures and convection rates allows us to interpret these signals as the periodic release of hot overpressured gas bubbles at the lake surface.

  17. Active shape models incorporating isolated landmarks for medical image annotation

    NASA Astrophysics Data System (ADS)

    Norajitra, Tobias; Meinzer, Hans-Peter; Stieltjes, Bram; Maier-Hein, Klaus H.

    2014-03-01

    Apart from their robustness in anatomic surface segmentation, purely surface based 3D Active Shape Models lack the ability to automatically detect and annotate non-surface key points of interest. However, annotation of anatomic landmarks is desirable, as it yields additional anatomic and functional information. Moreover, landmark detection might help to further improve accuracy during ASM segmentation. We present an extension of surface-based 3D Active Shape Models incorporating isolated non-surface landmarks. Positions of isolated and surface landmarks are modeled conjoint within a point distribution model (PDM). Isolated landmark appearance is described by a set of haar-like features, supporting local landmark detection on the PDM estimates using a kNN-Classi er. Landmark detection was evaluated in a leave-one-out cross validation on a reference dataset comprising 45 CT volumes of the human liver after shape space projection. Depending on the anatomical landmark to be detected, our experiments have shown in about 1/4 up to more than 1/2 of all test cases a signi cant improvement in detection accuracy compared to the position estimates delivered by the PDM. Our results encourage further research with regard to the combination of shape priors and machine learning for landmark detection within the Active Shape Model Framework.

  18. Medical Image Segmentation Based on a Hybrid Region-Based Active Contour Model

    PubMed Central

    Liu, Tingting; Xu, Haiyong; Liu, Zhen; Zhao, Yiming; Tian, Wenzhe

    2014-01-01

    A novel hybrid region-based active contour model is presented to segment medical images with intensity inhomogeneity. The energy functional for the proposed model consists of three weighted terms: global term, local term, and regularization term. The total energy is incorporated into a level set formulation with a level set regularization term, from which a curve evolution equation is derived for energy minimization. Experiments on some synthetic and real images demonstrate that our model is more efficient compared with the localizing region-based active contours (LRBAC) method, proposed by Lankton, and more robust compared with the Chan-Vese (C-V) active contour model. PMID:25028593

  19. Active catheter tracking using parallel MRI and real-time image reconstruction.

    PubMed

    Bock, Michael; Müller, Sven; Zuehlsdorff, Sven; Speier, Peter; Fink, Christian; Hallscheidt, Peter; Umathum, Reiner; Semmler, Wolfhard

    2006-06-01

    In this work active MR catheter tracking with automatic slice alignment was combined with an autocalibrated parallel imaging technique. Using an optimized generalized autocalibrating partially parallel acquisitions (GRAPPA) algorithm with an acceleration factor of 2, we were able to reduce the acquisition time per image by 34%. To accelerate real-time GRAPPA image reconstruction, the coil sensitivities were updated only after slice reorientation. For a 2D trueFISP acquisition (160 x 256 matrix, 80% phase matrix, half Fourier acquisition, TR = 3.7 ms, GRAPPA factor = 2) real-time image reconstruction was achieved with up to six imaging coils. In a single animal experiment the method was used to steer a catheter from the vena cava through the beating heart into the pulmonary vasculature at an image update rate of about five images per second. Under all slice orientations, parallel image reconstruction was accomplished with only minor image artifacts, and the increased temporal resolution provided a sharp delineation of intracardial structures, such as the papillary muscle. PMID:16683261

  20. Tomographic image of a seismically active volcano: Mammoth Mountain, California

    USGS Publications Warehouse

    Dawson, Phillip B.; Chouet, Bernard A.; Pitt, Andrew M.

    2016-01-01

    High-resolution tomographic P wave, S wave, and VP/VS velocity structure models are derived for Mammoth Mountain, California, using phase data from the Northern California Seismic Network and a temporary deployment of broadband seismometers. An anomalous volume (5.1 × 109 to 5.9 × 1010m3) of low P and low S wave velocities is imaged beneath Mammoth Mountain, extending from near the surface to a depth of ∼2 km below sea level. We infer that the reduction in seismic wave velocities is due to the presence of CO2 distributed in oblate spheroid pores with mean aspect ratio α = 1.6 × 10−3 to 7.9 × 10−3 (crack-like pores) and mean gas volume fraction ϕ = 8.1 × 10−4 to 3.4 × 10−3. The pore density parameter κ = 3ϕ/(4πα) = na3=0.11, where n is the number of pores per cubic meter and a is the mean pore equatorial radius. The total mass of CO2 is estimated to be 4.6 × 109 to 1.9 × 1011 kg. The local geological structure indicates that the CO2 contained in the pores is delivered to the surface through fractures controlled by faults and remnant foliation of the bedrock beneath Mammoth Mountain. The total volume of CO2 contained in the reservoir suggests that given an emission rate of 500 tons day−1, the reservoir could supply the emission of CO2 for ∼25–1040 years before depletion. Continued supply of CO2 from an underlying magmatic system would significantly prolong the existence of the reservoir.

  1. Tomographic image of a seismically active volcano: Mammoth Mountain, California

    NASA Astrophysics Data System (ADS)

    Dawson, Phillip; Chouet, Bernard; Pitt, Andrew

    2016-01-01

    High-resolution tomographic P wave, S wave, and VP/VS velocity structure models are derived for Mammoth Mountain, California, using phase data from the Northern California Seismic Network and a temporary deployment of broadband seismometers. An anomalous volume (5.1 × 109 to 5.9 × 1010m3) of low P and low S wave velocities is imaged beneath Mammoth Mountain, extending from near the surface to a depth of ˜2 km below sea level. We infer that the reduction in seismic wave velocities is due to the presence of CO2 distributed in oblate spheroid pores with mean aspect ratio α = 1.6 × 10-3 to 7.9 × 10-3 (crack-like pores) and mean gas volume fraction ϕ = 8.1 × 10-4 to 3.4 × 10-3. The pore density parameter κ = 3ϕ/(4πα) = na3=0.11, where n is the number of pores per cubic meter and a is the mean pore equatorial radius. The total mass of CO2 is estimated to be 4.6 × 109 to 1.9 × 1011 kg. The local geological structure indicates that the CO2 contained in the pores is delivered to the surface through fractures controlled by faults and remnant foliation of the bedrock beneath Mammoth Mountain. The total volume of CO2 contained in the reservoir suggests that given an emission rate of 500 tons day-1, the reservoir could supply the emission of CO2 for ˜25-1040 years before depletion. Continued supply of CO2 from an underlying magmatic system would significantly prolong the existence of the reservoir.

  2. Tomographic Image of a Seismically Active Volcano: Mammoth Mountain, California

    NASA Astrophysics Data System (ADS)

    Dawson, P. B.; Chouet, B. A.; Pitt, A. M.

    2015-12-01

    High-resolution tomographic P wave, S wave, and VP /VS velocity structure models are derived for Mammoth Mountain, California using phase data from the Northern California Seismic Network and a temporary deployment of broadband seismometers. An anomalous volume (˜50 km3) of low P and low S wave velocities is imaged beneath Mammoth Mountain, extending from near the surface to a depth of ˜2 km below sea level. We infer that the reduction in seismic wave velocities is primarily due to the presence of CO2 distributed in oblate-spheroid pores with mean aspect ratio α ˜8 x 10-4 (crack-like pores) and gas volume fraction φ ˜4 x 10-4. The pore density parameter κ = 3φ / (4πα) = na3 = 0.12, where n is the number of pores per cubic meter and a is the mean pore equatorial radius. The total mass of CO2 is estimated to range up to ˜1.6 x 1010 kg if the pores exclusively contain CO2, although he presence of an aqueous phase may lower this estimate by up to one order of magnitude. The local geological structure indicates that the CO2 contained in the pores is delivered to the surface through fractures controlled by faults and remnant foliation of the bedrock beneath Mammoth Mountain. The total volume of CO2 contained in the reservoir suggests that given an emission rate of 5 x 105 kg day-1, the reservoir could supply the emission of CO2 for ˜8 to ˜90 years before depletion. Continued supply of CO2 from an underlying magmatic system would significantly prolong the existence of the reservoir.

  3. Evaluation of activity images in dynamics speckle in search of objective estimators

    NASA Astrophysics Data System (ADS)

    Avendaño Montecinos, Marcos; Mora Canales, Victor; Cap, Nelly; Grumel, Eduardo; Rabal, Hector; Trivi, Marcelo; Baradit, Erik

    2015-08-01

    We explore the performance of two algorithms to screen loci of equal activity in dynamic speckle images. Dynamic speckle images are currently applied to several applications in medicine, biology, agriculture and other disciplines. Nevertheless, no objective standard has been proposed so far to evaluate the performance of the algorithms, which must be then relied on subjective appreciations. We use two case studies of activity that do not bear the biologic inherent variability to test the methods: "Generalized Differences" and "Fujii", looking for a standard to evaluate their performance in an objective way. As study cases, we use the drying of paint on an (assumed) unknown topography, namely the surface of a coin, and the activity due to pre heating a piece of paper that hides writings in the surface under the paper. A known object of simple topography is included in the image, besides of the painted coin, consisting in a paint pool where the depth is a linear function of its position. Both algorithms are applied to the images and the intensity profile of the results along the linear region of the pool activity is used to estimate the depth of the geometric topography hidden under paint in the coin. The accuracy of the result is used as a merit estimation of the corresponding algorithm. In the other experiment, a hidden dark bar printed on paper is covered with one or two paper leaves, slightly pre heated with a lamp and activity images registered and processed with both algorithms. The intensity profile of the activity images is used to estimate which method gives a better description of the bar edges images and their deterioration. Experimental results are shown.

  4. Positive affect modulates activity in the visual cortex to images of high calorie foods.

    PubMed

    Killgore, William D S; Yurgelun-Todd, Deborah A

    2007-05-01

    Activity within the visual cortex can be influenced by the emotional salience of a stimulus, but it is not clear whether such cortical activity is modulated by the affective status of the individual. This study used functional magnetic resonance imaging (fMRI) to examine the relationship between affect ratings on the Positive and Negative Affect Schedule and activity within the occipital cortex of 13 normal-weight women while viewing images of high calorie and low calorie foods. Regression analyses revealed that when participants viewed high calorie foods, Positive Affect correlated significantly with activity within the lingual gyrus and calcarine cortex, whereas Negative Affect was unrelated to visual cortex activity. In contrast, during presentations of low calorie foods, affect ratings, regardless of valence, were unrelated to occipital cortex activity. These findings suggest a mechanism whereby positive affective state may affect the early stages of sensory processing, possibly influencing subsequent perceptual experience of a stimulus. PMID:17464782

  5. Spatiotemporal relations of primary sensorimotor and secondary motor activation patterns mapped by NIR imaging

    PubMed Central

    Khan, Bilal; Chand, Pankaj; Alexandrakis, George

    2011-01-01

    Functional near infrared (fNIR) imaging was used to identify spatiotemporal relations between spatially distinct cortical regions activated during various hand and arm motion protocols. Imaging was performed over a field of view (FOV, 12 x 8.4 cm) including the secondary motor, primary sensorimotor, and the posterior parietal cortices over a single brain hemisphere. This is a more extended FOV than typically used in current fNIR studies. Three subjects performed four motor tasks that induced activation over this extended FOV. The tasks included card flipping (pronation and supination) that, to our knowledge, has not been performed in previous functional magnetic resonance imaging (fMRI) or fNIR studies. An earlier rise and a longer duration of the hemodynamic activation response were found in tasks requiring increased physical or mental effort. Additionally, analysis of activation images by cluster component analysis (CCA) demonstrated that cortical regions can be grouped into clusters, which can be adjacent or distant from each other, that have similar temporal activation patterns depending on whether the performed motor task is guided by visual or tactile feedback. These analyses highlight the future potential of fNIR imaging to tackle clinically relevant questions regarding the spatiotemporal relations between different sensorimotor cortex regions, e.g. ones involved in the rehabilitation response to motor impairments. PMID:22162826

  6. Research on long-range laser active imaging system applied in adverse weather conditions

    NASA Astrophysics Data System (ADS)

    Gai, Zhi-gang; Liu, Meng-de; Yang, Li; Kabanov, V. V.; Shi, Lei; Zhao, Jie; Chu, Shi-bo; Yang, Jun-xian; Zhou, Yang

    2013-09-01

    A low-light level night vision device or thermal infrared imager belonging to passive imaging system is generally used in daily target detection and identification. But in adverse weather conditions of dark of night, poor atmospheric transmission characteristics or strong backscattering (fog, dust, rain, snow, etc.), even the most sensitive low-light level night vision could not provide enough image resolution for detecting and identifying targets, and the thermal infrared imager is also limited by low temperature contrast. A long-range laser active imaging system, in combination with high-power semiconductor pulsed lasers with collimation technology, receiving objective lens of large diameter, long focal length and narrow viewing angle, high-gain image intensifier CCD (ICCD) camera and range-gated synchronization control technology, is developed for long distance target detection and high resolution imaging in adverse weather conditions. The system composition and operating principle are introduced. The extremely powerful and efficient illuminators with collimation technology are able to deliver uniform beams, which are essential for illuminating targets at a distance and generating high-quality images. The particular receiving objective lens, ICCD camera and range-gated synchronization control technology could reduce strong backscattering signal and improve imaging signal-to-noise ratio. The laboratory and outfield experiments have been done to validate imaging effect and imaging quality. The results show that the minimum resolution is about 3-5cm, 10cm, and greater than 20 cm for target far from 1100m, 4700m, and 6700m respectively in dark of night. Furthermore, the minimum resolution could reach to 10cm and 20cm for target far from 2500m and 4800m respectively and the image is too blurred to accurately identify the target when observing the target far from 7200m in rainy condition.

  7. The image of scientific researchers and their activity in Greek adolescents' drawings.

    PubMed

    Christidou, Vasilia; Hatzinikita, Vassilia; Samaras, Giannis

    2012-07-01

    The image prevailing among the public of scientific research and researchers constitutes a contradictory and complex combination of traditional stereotypes. We explore central facets of the image of scientific research and researchers as reflected in Greek adolescent students' drawings. Drawings were produced by 171 students participating in a drawing competition launched in the context of the "Researchers' Night 2007" implemented by three research institutions in Greece. Analysis of students' drawings involved dimensions related to the image of scientific researchers and of scientific research. Outcomes indicate that the students hold fairly outdated views of scientific researchers and their activity, involving stereotypic views of scientists and science, as well as gender stereotypes. Therefore there is an urgent need to promote a more relevant image of scientific researchers and their activity to young people and especially students. PMID:23823169

  8. Super-Resolution Ultrasound Imaging in Vivo with Transient Laser-Activated Nanodroplets.

    PubMed

    Luke, Geoffrey P; Hannah, Alexander S; Emelianov, Stanislav Y

    2016-04-13

    We have developed a method for super-resolution ultrasound imaging, which relies on a new class of blinking nanometer-size contrast agents: laser-activated nanodroplets (LANDs). The LANDs can be repeatedly optically triggered to undergo vaporization; the resulting spatially stationary, temporally transient microbubbles provide high ultrasound contrast for several to hundreds of milliseconds before recondensing to their native liquid nanodroplet state. By capturing high frame rate ultrasound images of blinking LANDs, we demonstrate the ability to detect individual recondensation events. Then we apply a newly developed super-resolution image processing algorithm to localize the LAND positions in vivo almost an order of magnitude better than conventional ultrasound imaging. These results pave the way for high resolution molecular imaging deep in tissue. PMID:27035761

  9. Stomatal Ultrastructure, Molecular Phylogeny, and Description of Parasitodiplogaster laevigata n. sp. (Nematoda: Diplogastridae), a Parasite of Fig Wasps

    PubMed Central

    Giblin-Davis, Robin M.; Ye, Weimin; Kanzaki, Natsumi; Williams, Donna; Morris, Krystalynne; Thomas, W. Kelley

    2006-01-01

    Parasitodiplogaster comprises a potentially large radiation of nematode species that appear to be parasitically bound to their Agaonid fig wasp hosts, which are mutualistically associated in the syconia (figs) of the diverse plant genus Ficus. Parasitodiplogaster laevigata n. sp. is described and illustrated as an associate of the fig wasp, Pegoscapus sp. from Ficus laevigata from southern Florida. It is the first species of Parasitodiplogaster reported from North America and is closest to P. trigonema from F. trigonata from Panama. Parasitodiplogaster laevigata n. sp. can be differentiated from all described species of Parasitodiplogaster based on stomatal morphology (presence of a large dorsal and a right subventral tooth) in the adults of both sexes, molecular comparisons of two expansion segments (D2,D3) of the large subunit (LSU) rRNAgene, and fig-fig wasp host affinities. The ultrastructure of P. laevigata n. sp. was elucidated using TEM and SEM for comparisons with other species of Parasitodiplogaster. The stoma of P. laevigata n. sp. possesses a nonsegmented cheilostomal ring that connects to the longitudinal body musculature per- and interradially, a claw-like dorsal tooth, a right subventral tooth, and telostegostomatal apodemes arising from the dorsal side of each subventral sector. The unification of the pro-, meso-, and metastegostom with the gymnostom in P. laevigata n. sp. and further simplification in other described species may be due to derived adaptations associated with the internal parasitism of fig wasps. PMID:19259439

  10. Active polarization imaging system to discriminate adaptively with diagonal Mueller matrix

    NASA Astrophysics Data System (ADS)

    Geng, Lixiang; Chen, Qian; Qian, Weixian; Gu, Guohua

    2015-11-01

    A promising method to optimize the polarization state of two-channel active polarization imaging system is presented. In this method, it is seminal that the detecting function of the imaging system is regarded as a discriminant projection of the observed objects' polarization features (elements of the Mueller matrix). The polarization state can be seen as a physical classifier which can be obtained by training samples. The image acquired with the system that has the designed optimal polarization state become discriminative results directly. The effectiveness of the proposed method and the discriminative ability of the optimal polarization state are demonstrated by the experimental results.

  11. STEM Imaging of Single Pd Atoms in Activated Carbon Fibers Considered for Hydrogen Storage

    SciTech Connect

    Van Benthem, Klaus; Bonifacio, Cecile S; Contescu, Cristian I; Pennycook, Stephen J; Gallego, Nidia C

    2011-01-01

    Aberration corrected scanning transmission electron microscopy was used to demonstrate the feasibility of imaging individual Pd atoms that are highly dispersed throughout the volume of activated carbon fibers. Simultaneous acquisition of high-angle annular dark-field and bright-field images allows correlation of the location of single Pd atoms with microstructural features of the carbon host material. Sub-Angstrom imaging conditions revealed that 18 wt% of the total Pd content is dispersed as single Pd atoms in three re-occurring local structural arrangements. The identified structural configurations may represent effective storage sites for molecular hydrogen through Kubas complex formation as discussed in detail in the preceding article.

  12. Active and passive acoustic imaging inside a large-scale polyaxial hydraulic fracture test

    SciTech Connect

    Glaser, S.D.; Dudley, J.W. II; Shlyapobersky, J.

    1999-07-01

    An automated laboratory hydraulic fracture experiment has been assembled to determine what rock and treatment parameters are crucial to improving the efficiency and effectiveness of field hydraulic fractures. To this end a large (460 mm cubic sample) polyaxial cell, with servo-controlled X,Y,Z, pore pressure, crack-mouth-opening-displacement, and bottom hole pressure, was built. Active imaging with embedded seismic diffraction arrays images the geometry of the fracture. Preliminary tests indicate fracture extent can be imaged to within 5%. Unique embeddible high-fidelity particle velocity AE sensors were designed and calibrated to allow determination of fracture source kinematics.

  13. Strength Training Improves Body Image and Physical Activity Behaviors Among Midlife and Older Rural Women

    PubMed Central

    Seguin, Rebecca A.; Eldridge, Galen; Lynch, Wesley; Paul, Lynn C.

    2015-01-01

    The effect of strength training on body image is understudied. The Strong Women Program, a 10-week, twice weekly strength-training program, was provided by Extension agents to 341 older rural women (62±12 years); changes in body image and other psychosocial variables were evaluated. Paired-sample t-test analyses were conducted to assess mean differences pre- to post-program. Strength training was associated with significant improvements in several dimensions of body image, health-related quality of life, and physical activity behaviors, satisfaction, and comfort among rural aging women—an often underserved population that stands to benefit considerably from similar programs. PMID:25767297

  14. Review of development of laser active imaging technology in China and foreign countries

    NASA Astrophysics Data System (ADS)

    Fan, Youchen; Zhao, Hongli; Li, Yingcun

    2014-11-01

    Range-gated laser active imaging technology is an effective way to image detection and precise tracking of remote, dark, and small targets that overcomes the shortcomings of passive visible or infrared imaging technology, thus has important practical value and broad application prospects in the military. The paper based on the analysis of its principle, technical advantages and key technologies focus on the typical systems under atmospheric conditions at home and abroad and the latest research results, and discusses the development trends of this technology.

  15. Near-infrared microscopy imaging for quantitative analysis of active component in counterfeit imidacloprid

    NASA Astrophysics Data System (ADS)

    Huang, Yue; Cao, Jinli; Ye, Shengfeng; Duan, Jia; Wu, Lijun; Li, Qianqian; Min, Shungeng

    2012-01-01

    Near-infrared (NIR) imaging systems simultaneously record spectral and spatial information. Near-infrared imaging was applied to the identification of imidacloprid in both artificially mixed samples and commercial formulation in this study. The distributions of technical imidacloprid and additive in the heterogeneous counterfeit were obtained by the relationship imaging (RI) mode. Furthermore a series of samples which consisted of different contents of uniformly distributed imidacloprid were prepared and three data cubes were generated at each content. Extracted spectra from those images were imported to establish the partial least squares model. The model's results were: R2 99.21%, RMSEC 0.0306, RMSECV 0.0183, RMSECV/mean value 0.0348 and RSEP 0.0784. The prediction relative error of commercial formulation is 0.0680, indicating the predicted value was correlated to the real content. Lastly the chemical value reconstruction image of imidacloprid formulation products was calculated by MATLAB program. NIR microscopy imaging manifests herein its potential in qualitatively identifying the active component in counterfeit pesticide and quantifying the active component in scanned image.

  16. Emerging liquid crystal waveguide technology for low SWaP active short-wave infrared imagers

    NASA Astrophysics Data System (ADS)

    Keller, Sean D.; Uyeno, Gerald P.; Lynch, Ted; Davis, Scott R.; Rommel, Scott D.; Pino, Juan

    2015-03-01

    Raytheon's innovative active short wave infrared (SWIR) imager uses Vescent Photonic's emerging liquid crystal waveguide (LCWG) technology to continuously steer the illumination laser beam over the imager field of view (FOV). This approach instantly illuminates a very small fraction of the FOV, which significantly reduces the laser power compared to flash illumination. This reduced laser power directly leads to a reduction in the size, weight and power (SWaP) of the laser. The reduction in laser power reduces the input power and thermal rejection, which leads to additional reduction in the SWaP of the power supplies and thermal control. The high-speed steering capability of the LCWG enables the imager's SWaP reduction. The SWaP reduction is possible using either global or rolling shutter detectors. In both cases, the LCWG steers the laser beam over the entire FOV while the detector is integrating. For a rolling shutter detector, the LCWG synchronizes the steering with the rolling shutter to illuminate only regions currently integrating. Raytheon's approach enables low SWaP active SWIR imagers without compromising image quality. This paper presents the results of Raytheon's active SWIR imager demonstration including steering control and synchronization with the detector integration.

  17. Experiments and models of active and thermal imaging under bad weather conditions

    NASA Astrophysics Data System (ADS)

    Bernard, Erwan; Riviere, Nicolas; Renaudat, Mathieu; Guiset, Pierrick; Pealat, Michel; Zenou, Emmanuel

    2013-10-01

    Thermal imaging cameras are widely used in military contexts for their night vision capabilities and their observation range; there are based on passive infrared sensors (e.g. MWIR or LWIR range). Under bad weather conditions or when the target is partially hidden (e.g. foliage, military camouflage) they are more and more complemented by active imaging systems, a key technology to perform target identification at long range. The 2D flash imaging technique is based on a high powered pulsed laser source that illuminates the entire scene and a fast gated camera as the imaging system. Both technologies are well experienced under clear meteorological conditions; models including atmospheric effects such as turbulence are able to predict accurately their performances. However, under bad weather conditions such as rain, haze or snow, these models are not relevant. This paper introduces new models to predict performances under bad weather conditions for both active and infrared imaging systems. We point out their effects on controlled physical parameters (extinction, transmission, spatial resolution, thermal background, speckle, turbulence). Then we develop physical models to describe their intrinsic characteristics and their impact on the imaging system performances. Finally, we approximate these models to have a "first order" model easy to deploy for industrial applications. This theoretical work will be validated on real active and infrared data.

  18. In vivo imaging and biochemical characterization of protease function using fluorescent activity-based probes

    PubMed Central

    Edgington, Laura E.; Bogyo, Matthew

    2013-01-01

    Activity-based probes (ABPs) are reactive small molecules that covalently bind to active enzymes. When tagged with a fluorophore, ABPs serve as powerful tools to investigate enzymatic activity across a wide variety of applications. In this article, we will provide detailed protocols for using fluorescent ABPs to biochemically characterize the activity of proteases in vitro. Furthermore, we will describe how these probes can be applied to image protease activity in live animals and tissues along with subsequent analysis by histology, flow cytometry, and SDS-PAGE. PMID:23788323

  19. Optimization of wavelengths sets for multispectral reflectance imaging of rat olfactory bulb activation in vivo

    NASA Astrophysics Data System (ADS)

    Renaud, Rémi; Bendahmane, Mounir; Chery, Romain; Martin, Claire; Gurden, Hirac; Pain, Frederic

    2012-06-01

    Wide field multispectral imaging of light backscattered by brain tissues provides maps of hemodynamics changes (total blood volume and oxygenation) following activation. This technique relies on the fit of the reflectance images obtain at two or more wavelengths using a modified Beer-Lambert law1,2. It has been successfully applied to study the activation of several sensory cortices in the anesthetized rodent using visible light1-5. We have carried out recently the first multispectral imaging in the olfactory bulb6 (OB) of anesthetized rats. However, the optimization of wavelengths choice has not been discussed in terms of cross talk and uniqueness of the estimated parameters (blood volume and saturation maps) although this point was shown to be crucial for similar studies in Diffuse Optical Imaging in humans7-10. We have studied theoretically and experimentally the optimal sets of wavelength for multispectral imaging of rodent brain activation in the visible. Sets of optimal wavelengths have been identified and validated in vivo for multispectral imaging of the OB of rats following odor stimulus. We studied the influence of the wavelengths sets on the magnitude and time courses of the oxy- and deoxyhemoglobin concentration variations as well as on the spatial extent of activated brain areas following stimulation. Beyond the estimation of hemodynamic parameters from multispectral reflectance data, we observed repeatedly and for all wavelengths a decrease of light reflectance. For wavelengths longer than 590 nm, these observations differ from those observed in the somatosensory and barrel cortex and question the basis of the reflectance changes during activation in the OB. To solve this issue, Monte Carlo simulations (MCS) have been carried out to assess the relative contribution of absorption, scattering and anisotropy changes to the intrinsic optical imaging signals in somatosensory cortex (SsC) and OB model.

  20. Petrological imaging of an active pluton beneath Cerro Uturuncu, Bolivia

    NASA Astrophysics Data System (ADS)

    Muir, Duncan D.; Blundy, Jon D.; Hutchinson, Michael C.; Rust, Alison C.

    2014-03-01

    Uturuncu is a dormant volcano in the Altiplano of SW Bolivia. A present day ~70 km diameter interferometric synthetic aperture radar (InSAR) anomaly roughly centred on Uturuncu's edifice is believed to be a result of magma intrusion into an active crustal pluton. Past activity at the volcano, spanning 0.89 to 0.27 Ma, is exclusively effusive and almost all lavas and domes are dacitic with phenocrysts of plagioclase, orthopyroxene, biotite, ilmenite and Ti-magnetite plus or minus quartz, and microlites of plagioclase and orthopyroxene set in rhyolitic groundmass glass. Plagioclase-hosted melt inclusions (MI) are rhyolitic with major element compositions that are similar to groundmass glasses. H2O concentrations plotted versus incompatible elements for individual samples describe a trend typical of near-isobaric, volatile-saturated crystallisation. At 870 °C, the average magma temperature calculated from Fe-Ti oxides, the average H2O of 3.2 ± 0.7 wt% and CO2 typically <160 ppm equate to MI trapping pressures of 50-120 MPa, approximately 2-4.5 km below surface. Such shallow storage precludes the role of dacite magma emplacement into pre-eruptive storage regions as being the cause of the observed InSAR anomaly. Storage pressures, whole-rock (WR) chemistry and phase assemblage are remarkably consistent across the eruptive history of the volcano, although magmatic temperatures calculated from Fe-Ti oxide geothermometry, zircon saturation thermometry using MI and orthopyroxene-melt thermometry range from 760 to 925 °C at NNO ± 1 log. This large temperature range is similar to that of saturation temperatures of observed phases in experimental data on Uturuncu dacites. The variation in calculated temperatures is attributed to piecemeal construction of the active pluton by successive inputs of new magma into a growing volume of plutonic mush. Fluctuating temperatures within the mush can account for sieve-textured cores and complex zoning in plagioclase phenocrysts

  1. X-ray imaging of chemically active valence electrons during a pericyclic reaction

    NASA Astrophysics Data System (ADS)

    Bredtmann, Timm; Ivanov, Misha; Dixit, Gopal

    2014-11-01

    Time-resolved imaging of chemically active valence electron densities is a long-sought goal, as these electrons dictate the course of chemical reactions. However, X-ray scattering is always dominated by the core and inert valence electrons, making time-resolved X-ray imaging of chemically active valence electron densities extremely challenging. Here we demonstrate an effective and robust method, which emphasizes the information encoded in weakly scattered photons, to image chemically active valence electron densities. The degenerate Cope rearrangement of semibullvalene, a pericyclic reaction, is used as an example to visually illustrate our approach. Our work also provides experimental access to the long-standing problem of synchronous versus asynchronous bond formation and breaking during pericyclic reactions.

  2. Raster image cross-correlation analysis for spatiotemporal visualization of intracellular degradation activities against exogenous DNAs.

    PubMed

    Sasaki, Akira; Yamamoto, Johtaro; Jin, Takashi; Kinjo, Masataka

    2015-01-01

    Reducing intracellular DNA degradation is critical to enhance the efficiency of gene therapy. Exogenous DNA incorporation into cells is strictly blocked by the defense machinery of intracellular nuclease activity. Raster image correlation spectroscopy (RICS) and raster image cross-correlation spectroscopy (cross-correlation RICS; ccRICS) are image-based correlation methods. These powerful tools allow the study of spatiotemporal molecular dynamics. Here we performed spatiotemporal ccRICS analyses of fluorescent DNA and directly monitored the process of exogenous DNA degradation in living cell cytoplasm. Such direct monitors of DNA degradation allow us to determine the fate of the exogenous DNA in living cells. On comparing the process in living cells, our study shows that cytoplasmic nuclease activity differs between cell lines; therefore, we propose that the difference of nuclease activity in cytoplasm dictates a different resistance to exogenous DNA incorporation. New insight on efficient gene delivery can be provided with our study. PMID:26400011

  3. Transform-invariant feature based functional MR image registration and neural activity modelling.

    PubMed

    Gong, Jiaqi; Hao, Qi; Hu, Fei

    2013-01-01

    In this paper, a set of non-rigid image registration and neural activity modelling methods using functional MR Images (fMRI) are proposed based on transform-invariant feature representations. Our work made two contributions. First, we propose to use a transform-invariant feature to improve image registration performance of Iterative Closest Point (ICP) based methods. The proposed feature utilises Gaussian Mixture Models (GMM) to describe the local topological structure of fMRI data. Second, we propose to use a 3-dimensional Scale-Invariant Feature Transform (SIFT) based descriptor to represent neural activities related to drinking behaviour. As a result, neural activities patterns of different subjects drinking water or intaking glucose can be recognised, with strong robustness against various artefacts. PMID:23900434

  4. X-ray imaging of chemically active valence electrons during a pericyclic reaction

    PubMed Central

    Bredtmann, Timm; Ivanov, Misha; Dixit, Gopal

    2014-01-01

    Time-resolved imaging of chemically active valence electron densities is a long-sought goal, as these electrons dictate the course of chemical reactions. However, X-ray scattering is always dominated by the core and inert valence electrons, making time-resolved X-ray imaging of chemically active valence electron densities extremely challenging. Here we demonstrate an effective and robust method, which emphasizes the information encoded in weakly scattered photons, to image chemically active valence electron densities. The degenerate Cope rearrangement of semibullvalene, a pericyclic reaction, is used as an example to visually illustrate our approach. Our work also provides experimental access to the long-standing problem of synchronous versus asynchronous bond formation and breaking during pericyclic reactions. PMID:25424639

  5. Raster image cross-correlation analysis for spatiotemporal visualization of intracellular degradation activities against exogenous DNAs

    PubMed Central

    Sasaki, Akira; Yamamoto, Johtaro; Jin, Takashi; Kinjo, Masataka

    2015-01-01

    Reducing intracellular DNA degradation is critical to enhance the efficiency of gene therapy. Exogenous DNA incorporation into cells is strictly blocked by the defense machinery of intracellular nuclease activity. Raster image correlation spectroscopy (RICS) and raster image cross-correlation spectroscopy (cross-correlation RICS; ccRICS) are image-based correlation methods. These powerful tools allow the study of spatiotemporal molecular dynamics. Here we performed spatiotemporal ccRICS analyses of fluorescent DNA and directly monitored the process of exogenous DNA degradation in living cell cytoplasm. Such direct monitors of DNA degradation allow us to determine the fate of the exogenous DNA in living cells. On comparing the process in living cells, our study shows that cytoplasmic nuclease activity differs between cell lines; therefore, we propose that the difference of nuclease activity in cytoplasm dictates a different resistance to exogenous DNA incorporation. New insight on efficient gene delivery can be provided with our study. PMID:26400011

  6. Advances in multifocal methods for imaging human brain activity

    NASA Astrophysics Data System (ADS)

    Carney, Thom; Ales, Justin; Klein, Stanley A.

    2006-02-01

    The typical multifocal stimulus used in visual evoked potential (VEP) studies consists of about 60 checkerboard stimulus patches each independently contrast reversed according to an m-sequence. Cross correlation of the response (EEG, MEG, ERG, or fMRI) with the m-sequence results in a series of response kernels for each response channel and each stimulus patch. In the past the number and complexity of stimulus patches has been constrained by graphics hardware, namely the use of look-up-table (LUT) animation methods. To avoid such limitations we replaced the LUTs with true color graphic sprites to present arbitrary spatial patterns. To demonstrate the utility of the method we have recorded simultaneously from 192 cortically scaled stimulus patches each of which activate about 12mm2 of cortex in area V1. Because of the sparseness of cortical folding, very small stimulus patches and robust estimation of dipole source orientation, the method opens a new window on precise spatio-temporal mapping of early visual areas. The use of sprites also enables multiplexing stimuli such that at each patch location multiple stimuli can be presented. We have presented patterns with different orientations (or spatial frequencies) at the same patch locations but independently temporally modulated, effectively doubling the number of stimulus patches, to explore cell population interactions at the same cortical locus. We have also measured nonlinear responses to adjacent pairs of patches, thereby getting an edge response that doubles the spatial sampling density to about 1.8 mm on cortex.

  7. Simulated 3D ultrasound LV cardiac images for active shape model training

    NASA Astrophysics Data System (ADS)

    Butakoff, Constantine; Balocco, Simone; Ordas, Sebastian; Frangi, Alejandro F.

    2007-03-01

    In this paper a study of 3D ultrasound cardiac segmentation using Active Shape Models (ASM) is presented. The proposed approach is based on a combination of a point distribution model constructed from a multitude of high resolution MRI scans and the appearance model obtained from simulated 3D ultrasound images. Usually the appearance model is learnt from a set of landmarked images. The significant level of noise, the low resolution of 3D ultrasound images (3D US) and the frequent failure to capture the complete wall of the left ventricle (LV) makes automatic or manual landmarking difficult. One possible solution is to use artificially simulated 3D US images since the generated images will match exactly the shape in question. In this way, by varying simulation parameters and generating corresponding images, it is possible to obtain a training set where the image matches the shape exactly. In this work the simulation of ultrasound images is performed by a convolutional approach. The evaluation of segmentation accuracy is performed on both simulated and in vivo images. The results obtained on 567 simulated images had an average error of 1.9 mm (1.73 +/- 0.05 mm for epicardium and 2 +/- 0.07 mm for endocardium, with 95% confidence) with voxel size being 1.1 × 1.1 × 0.7 mm. The error on 20 in vivo data was 3.5 mm (3.44 +/- 0.4 mm for epicardium and 3.73 +/- 0.4 mm for endocardium). In most images the model was able to approximate the borders of myocardium even when the latter was indistinguishable from the surrounding tissues.

  8. Estimation of neuronal activity based on voltage-sensitive dye imaging in a moving preparation.

    PubMed

    Fathiazar, Elham; Kretzberg, Jutta

    2015-01-01

    Voltage-sensitive dye imaging allows simultaneous recording of graded voltage changes of multiple neurons. While this experimental technique is a great tool to study neuronal network activity in neuroscience, the optical recording suffers from artifacts. In particular, bleaching of the dye and cell movement impede the analysis and interpretation of imaging results. In this paper, we present methods to tackle these two main artifacts. Cell movement during the experiment is corrected by an optical flow method. Bleaching decay is estimated based on a line fit of recordings without stimulus, which is subtracted from the rest of the recordings in the same experiment. Here, we use a leech ganglion as an example tissue to evaluate these processing procedures. This preparation allows simultaneous voltage-sensitive dye imaging of the entire neuronal network and intracellular recording of one cell's membrane voltage. Using the intracellularly recorded voltage as the ground truth reference, we show that our processing methods for the VSD imaging signal clearly improve the correlation between the real and the estimated voltage. Since other imaging techniques (e.g., calcium imaging) suffer from the same type of artifacts as voltage-sensitive dye imaging, our processing method might be useful for a wide range of biomedical imaging studies. PMID:26737729

  9. Fast range estimation based on active range-gated imaging for coastal surveillance

    NASA Astrophysics Data System (ADS)

    Kong, Qingshan; Cao, Yinan; Wang, Xinwei; Tong, Youwan; Zhou, Yan; Liu, Yuliang

    2012-11-01

    Coastal surveillance is very important because it is useful for search and rescue, illegal immigration, or harbor security and so on. Furthermore, range estimation is critical for precisely detecting the target. Range-gated laser imaging sensor is suitable for high accuracy range especially in night and no moonlight. Generally, before detecting the target, it is necessary to change delay time till the target is captured. There are two operating mode for range-gated imaging sensor, one is passive imaging mode, and the other is gate viewing mode. Firstly, the sensor is passive mode, only capturing scenes by ICCD, once the object appears in the range of monitoring area, we can obtain the course range of the target according to the imaging geometry/projecting transform. Then, the sensor is gate viewing mode, applying micro second laser pulses and sensor gate width, we can get the range of targets by at least two continuous images with trapezoid-shaped range intensity profile. This technique enables super-resolution depth mapping with a reduction of imaging data processing. Based on the first step, we can calculate the rough value and quickly fix delay time which the target is detected. This technique has overcome the depth resolution limitation for 3D active imaging and enables super-resolution depth mapping with a reduction of imaging data processing. By the two steps, we can quickly obtain the distance between the object and sensor.

  10. Active imaging with the aids of polarization retrieve in turbid media system

    NASA Astrophysics Data System (ADS)

    Tao, Qiangqiang; Sun, Yongxuan; Shen, Fei; Xu, Qiang; Gao, Jun; Guo, Zhongyi

    2016-01-01

    We propose a novel active imaging based on the polarization retrieve (PR) method in turbid media system. In our simulations, the Monte Carlo (MC) algorithm has been used to investigate the scattering process between the incident photons and the scattering particles, and the visually concordant object but with different polarization characteristics in different regions, has been selected as the original target that is placed in the turbid media. Under linearly and circularly polarized illuminations, the simulation results demonstrate that the corresponding polarization properties can provide additional information for the imaging, and the contrast of the polarization image can also be enhanced greatly compared to the simplex intensity image in the turbid media. Besides, the polarization image adjusted by the PR method can further enhance the visibility and contrast. In addition, by PR imaging method, with the increasing particles' size in Mie's scale, the visibility can be enhanced, because of the increased forward scattering effect. In general, in the same circumstance, the circular polarization images can offer a better contrast and visibility than that of linear ones. The results indicate that the PR imaging method is more applicable to the scattering media system with relatively larger particles such as aerosols, heavy fog, cumulus, and seawater, as well as to biological tissues and blood media.

  11. Effect of Radionuclide Activity Concentration on PET-CT Image Uniformity

    PubMed Central

    Hasford, Francis; Wyk, Bronwin Van; Mabhengu, Thulani; Vangu, Mboyo Di Tamba; Kyere, Augustine Kwame; Amuasi, John Humphrey

    2016-01-01

    Assessment of radionuclide activity concentration on positron emission tomography-computedr tomography (PET-CT) image uniformity has been carried out quantitatively. Tomographic PET-CT images of cylindrical phantom containing F-18 fluorodeoxyglucose (FDG) activity concentration was acquired and used for the assessment. Activity concentrations were varied and PET-CT images were acquired at the constant acquisition parameters of time, matrix size, and reconstruction algorithm, respectively. Using midtransaxial image slices, quantitative index of nonuniformity (NU), and coefficient of uniformity variation were estimated for the different activity concentrations. Maximum NUs of 17.6%, 26.3%, 32.7%, 36.2%, and 38.5% were estimated for activity concentrations of 16.87 kBq/mL, 14.06 kBq/mL, 11.25 kBq/mL, 8.43 kBq/mL, and 5.62 kBq/mL, respectively. The coefficient of uniformity variation established an inverse quadratic relationship with activity concentration. Activity concentrations of 16.87 kBq/mL, 14.06 kBq/mL, 11.25 kBq/mL, 8.43 kBq/mL, and 5.62 kBq/mL produced uniformity variations of 1.47%, 2.52%, 4.23%, 5.12%, and 4.98%, respectively. Increasing activity concentration resulted in decreasing coefficient of uniformity and hence, an increase in image uniformity. The uniformity estimates compared well with the standards set internationally. PMID:27134558

  12. Reconstruction of burst activity from calcium imaging of neuronal population via Lq minimization and interval screening

    PubMed Central

    Quan, Tingwei; Lv, Xiaohua; Liu, Xiuli; Zeng, Shaoqun

    2016-01-01

    Calcium imaging is becoming an increasingly popular technology to indirectly measure activity patterns in local neuronal networks. Based on the dependence of calcium fluorescence on neuronal spiking, two-photon calcium imaging affords single-cell resolution of neuronal population activity. However, it is still difficult to reconstruct neuronal activity from complex calcium fluorescence traces, particularly for traces contaminated by noise. Here, we describe a robust and efficient neuronal-activity reconstruction method that utilizes Lq minimization and interval screening (IS), which we refer to as LqIS. The simulation results show that LqIS performs satisfactorily in terms of both accuracy and speed of reconstruction. Reconstruction of simulation and experimental data also shows that LqIS has advantages in terms of the recall rate, precision rate, and timing error. Finally, LqIS is demonstrated to effectively reconstruct neuronal burst activity from calcium fluorescence traces recorded from large-size neuronal population. PMID:27375930

  13. Noninvasive imaging of sialyltransferase activity in living cells by chemoselective recognition.

    PubMed

    Bao, Lei; Ding, Lin; Yang, Min; Ju, Huangxian

    2015-01-01

    To elucidate the biological and pathological functions of sialyltransferases (STs), intracellular ST activity evaluation is necessary. Focusing on the lack of noninvasive methods for obtaining the dynamic activity information, this work designs a sensing platform for in situ FRET imaging of intracellular ST activity and tracing of sialylation process. The system uses tetramethylrhodamine isothiocyanate labeled asialofetuin (TRITC-AF) as a ST substrate and fluorescein isothiocyanate labeled 3-aminophenylboronic acid (FITC-APBA) as the chemoselective recognition probe of sialylation product, both of which are encapsulated in a liposome vesicle for cellular delivery. The recognition of FITC-APBA to sialylated TRITC-AF leads to the FRET signal that is analyzed by FRET efficiency images. This strategy has been used to evaluate the correlation of ST activity with malignancy and cell surface sialylation, and the sialylation inhibition activity of inhibitors. This work provides a powerful noninvasive tool for glycan biosynthesis mechanism research, cancer diagnostics and drug development. PMID:26046317

  14. Noninvasive imaging of sialyltransferase activity in living cells by chemoselective recognition

    NASA Astrophysics Data System (ADS)

    Bao, Lei; Ding, Lin; Yang, Min; Ju, Huangxian

    2015-06-01

    To elucidate the biological and pathological functions of sialyltransferases (STs), intracellular ST activity evaluation is necessary. Focusing on the lack of noninvasive methods for obtaining the dynamic activity information, this work designs a sensing platform for in situ FRET imaging of intracellular ST activity and tracing of sialylation process. The system uses tetramethylrhodamine isothiocyanate labeled asialofetuin (TRITC-AF) as a ST substrate and fluorescein isothiocyanate labeled 3-aminophenylboronic acid (FITC-APBA) as the chemoselective recognition probe of sialylation product, both of which are encapsulated in a liposome vesicle for cellular delivery. The recognition of FITC-APBA to sialylated TRITC-AF leads to the FRET signal that is analyzed by FRET efficiency images. This strategy has been used to evaluate the correlation of ST activity with malignancy and cell surface sialylation, and the sialylation inhibition activity of inhibitors. This work provides a powerful noninvasive tool for glycan biosynthesis mechanism research, cancer diagnostics and drug development.

  15. Following the Trajectory of Osteoarthritis Development Through Serial Near Infrared Fluorescence Imaging of MMP Activities

    PubMed Central

    Leahy, Averi A.; Esfahani, Shadi A.; Foote, Andrea T.; Hui, Carrie K.; Rainbow, Roshni S.; Nakamura, Daisy S.; Tracey, Brian H.; Mahmood, Umar; Zeng, Li

    2014-01-01

    Objectives A major hurdle in osteoarthritis (OA) research is the lack of sensitive detection and monitoring methods. It is hypothesized that proteases, such as matrix metalloproteinases (MMPs), are upregulated at early stages of OA development. The aim of this study was to investigate if a near infrared fluorescence (NIRF) probe activated by MMPs could visualize in vivo OA progression starting from its early stages. Methods Using an MMP activatable NIRF probe (MMPSense680), we assessed the upregulation of MMP activity in vitro by incubating human chondrocytes with the pro-inflammatory cytokine IL-1β. MMP activity was then evaluated in vivo serially in a chronic, injury-induced OA mouse model. For tracking MMP activity over time, mice were imaged 1 – 8 weeks post OA inducing surgery. Imaging results were correlated with histology. Results In vitro studies confirmed that NIRF imaging could identify enhanced MMP activity in IL-1β-treated human chondrocytes. In vivo imaging showed significantly higher fluorescent intensity in OA knees compared to sham knees (control) of the same mice. Additionally, the total emitted fluorescence intensity steadily increased over the entire course of OA progression that was examined. NIRF imaging results correlated with histological analysis, which showed an increase in articular cartilage structural damage over time. Conclusions Imaging of MMP activity in an OA mouse model provided sensitive and consistent visualization of OA progression, beginning from the early stages of OA. In addition to facilitating the preclinical study of OA modulators, this approach has the potential for future human translation. PMID:25385707

  16. Ionic contrast terahertz time resolved imaging of frog auricular heart muscle electrical activity

    NASA Astrophysics Data System (ADS)

    Masson, Jean-Baptiste; Sauviat, Martin-Pierre; Gallot, Guilhem

    2006-10-01

    The authors demonstrate the direct, noninvasive and time resolved imaging of functional frog auricular fibers by ionic contrast terahertz (ICT) near field microscopy. This technique provides quantitative, time-dependent measurement of ionic flow during auricular muscle electrical activity, and opens the way of direct noninvasive imaging of cardiac activity under stimulation. ICT microscopy technique was associated with full three-dimensional simulation enabling to measure precisely the fiber sizes. This technique coupled to waveguide technology should provide the grounds to development of advanced in vivo ion flux measurement in mammalian hearts, allowing the prediction of heart attack from change in K+ fluxes.

  17. Ka-band Dielectric Waveguide Antenna Array for Millimeter Wave Active Imaging System

    NASA Astrophysics Data System (ADS)

    Fang, Weihai; Fei, Peng; Nian, Feng; Yang, Yujie; Feng, Keming

    2014-11-01

    Ka-band compact dielectric waveguide antenna array for active imaging system is given. Antenna array with WR28 metal waveguide direct feeding is specially designed with small size, high gain, good radiation pattern, easy realization, low insertion loss and low mutual coupling. One practical antenna array for 3-D active imaging system is shown with theoretic analysis and experimental results. The mutual coupling of transmitting and receiving units is less than -30dB, the gain from 26.5GHz to 40GHz is (12-16) dB. The results in this paper provide guidelines for the designing of millimeter wave dielectric waveguide antenna array.

  18. Lag Synchronization of Switched Neural Networks via Neural Activation Function and Applications in Image Encryption.

    PubMed

    Wen, Shiping; Zeng, Zhigang; Huang, Tingwen; Meng, Qinggang; Yao, Wei

    2015-07-01

    This paper investigates the problem of global exponential lag synchronization of a class of switched neural networks with time-varying delays via neural activation function and applications in image encryption. The controller is dependent on the output of the system in the case of packed circuits, since it is hard to measure the inner state of the circuits. Thus, it is critical to design the controller based on the neuron activation function. Comparing the results, in this paper, with the existing ones shows that we improve and generalize the results derived in the previous literature. Several examples are also given to illustrate the effectiveness and potential applications in image encryption. PMID:25594985

  19. Fusing Passive and Active Sensed Images to Gain Infrared-Textured 3d Models

    NASA Astrophysics Data System (ADS)

    Weinmann, M.; Hoegner, L.; Leitloff, J.; Stilla, U.; Hinz, S.; Jutzi, B.

    2012-07-01

    Obtaining a 3D description of man-made and natural environments is a basic task in Computer Vision, Photogrammetry and Remote Sensing. New active sensors provide the possibility of capturing range information by images with a single measurement. With this new technique, image-based active ranging is possible which allows for capturing dynamic scenes, e.g. with moving pedestrians or moving vehicles. The currently available range imaging devices usually operate within the close-infrared domain to capture range and furthermore active and passive intensity images. Depending on the application, a 3D description with additional spectral information such as thermal-infrared data can be helpful and offers new opportunities for the detection and interpretation of human subjects and interactions. Therefore, thermal-infrared data combined with range information is promising. In this paper, an approach for mapping thermal-infrared data on range data is proposed. First, a camera calibration is carried out for the range imaging system (PMD[vision] CamCube 2.0) and the thermal-infrared system (InfraTec VarioCAM hr). Subsequently, a registration of close-infrared and thermal infrared intensity images derived from different sensor devices is performed. In this context, wavelength independent properties are selected in order to derive point correspondences between the different spectral domains. Finally, the thermal infrared images are enhanced with information derived from data acquired with the range imaging device and the enhanced IR texture is projected onto the respective 3D point cloud data for gaining appropriate infrared-textured 3D models. The feasibility of the proposed methodology is demonstrated for an experimental setup which is well-suited for investigating these proposed possibilities. Hence, the presented work is a first step towards the development of methods for combined thermal-infrared and range representation.

  20. Synthetic aperture microwave imaging with active probing for fusion plasma diagnostics

    NASA Astrophysics Data System (ADS)

    Shevchenko, Vladimir F.; Freethy, Simon J.; Huang, Billy K.; Vann, Roddy G. L.

    2014-08-01

    A Synthetic Aperture Microwave Imaging (SAMI) system has been designed and built to obtain 2-D images at several frequencies from fusion plasmas. SAMI uses a phased array of linearly polarised antennas. The array configuration has been optimised to achieve maximum synthetic aperture beam efficiency. The signals received by antennas are down-converted to the intermediate frequency range and then recorded in a full vector form. Full vector signals allow beam focusing and image reconstruction in both real time and a post-processing mode. SAMI can scan over 16 pre-programmed frequencies in the range of 10-35GHz with a switching time of 300ns. The system operates in 2 different modes simultaneously: both a 'passive' imaging of plasma emission and also an 'active' imaging of the back-scattered signal of the radiation launched by one of the antennas from the same array. This second mode is similar to so-called Doppler backscattering (DBS) reflectometry with 2-D resolution of the propagation velocity of turbulent structures. Both modes of operation show good performance in fusion plasma experiments on Mega Amp Spherical Tokamak (MAST). We have obtained the first ever 2-D images of BXO mode conversion windows. With active probing, first ever turbulence velocity maps have been obtained. We present an overview of the diagnostic and discuss recent results. In contrast to quasi-optical microwave imaging systems SAMI requires neither big aperture viewing ports nor large 2-D detector arrays to achieve the desired imaging resolution. The number of effective 'pixels' of the synthesized image is proportional to the number of receiving antennas squared. Thus only a small number of optimised antennas is sufficient for the majority of applications. Possible implementation of SAMI on ITERand DEMO is discussed.

  1. Synthetic aperture microwave imaging with active probing for fusion plasma diagnostics

    SciTech Connect

    Shevchenko, Vladimir F.; Freethy, Simon J.; Huang, Billy K.

    2014-08-21

    A Synthetic Aperture Microwave Imaging (SAMI) system has been designed and built to obtain 2-D images at several frequencies from fusion plasmas. SAMI uses a phased array of linearly polarised antennas. The array configuration has been optimised to achieve maximum synthetic aperture beam efficiency. The signals received by antennas are down-converted to the intermediate frequency range and then recorded in a full vector form. Full vector signals allow beam focusing and image reconstruction in both real time and a post-processing mode. SAMI can scan over 16 pre-programmed frequencies in the range of 10-35GHz with a switching time of 300ns. The system operates in 2 different modes simultaneously: both a 'passive' imaging of plasma emission and also an 'active' imaging of the back-scattered signal of the radiation launched by one of the antennas from the same array. This second mode is similar to so-called Doppler backscattering (DBS) reflectometry with 2-D resolution of the propagation velocity of turbulent structures. Both modes of operation show good performance in fusion plasma experiments on Mega Amp Spherical Tokamak (MAST). We have obtained the first ever 2-D images of BXO mode conversion windows. With active probing, first ever turbulence velocity maps have been obtained. We present an overview of the diagnostic and discuss recent results. In contrast to quasi-optical microwave imaging systems SAMI requires neither big aperture viewing ports nor large 2-D detector arrays to achieve the desired imaging resolution. The number of effective 'pixels' of the synthesized image is proportional to the number of receiving antennas squared. Thus only a small number of optimised antennas is sufficient for the majority of applications. Possible implementation of SAMI on ITERand DEMO is discussed.

  2. Spatial Scales of Genetic Structure in Free-Standing and Strangler Figs (Ficus, Moraceae) Inhabiting Neotropical Forests.

    PubMed

    Heer, Katrin; Kalko, Elisabeth K V; Albrecht, Larissa; García-Villacorta, Roosevelt; Staeps, Felix C; Herre, Edward Allen; Dick, Christopher W

    2015-01-01

    Wind-borne pollinating wasps (Agaonidae) can transport fig (Ficus sp., Moraceae) pollen over enormous distances (> 100 km). Because of their extensive breeding areas, Neotropical figs are expected to exhibit weak patterns of genetic structure at local and regional scales. We evaluated genetic structure at the regional to continental scale (Panama, Costa Rica, and Peru) for the free-standing fig species Ficus insipida. Genetic differentiation was detected only at distances > 300 km (Jost´s Dest = 0.68 ± 0.07 & FST = 0.30 ± 0.03 between Mesoamerican and Amazonian sites) and evidence for phylogeographic structure (RST>permuted RST) was only significant in comparisons between Central and South America. Further, we assessed local scale spatial genetic structure (SGS, d ≤ 8 km) in Panama and developed an agent-based model parameterized with data from F. insipida to estimate minimum pollination distances, which determine the contribution of pollen dispersal on SGS. The local scale data for F. insipida was compared to SGS data collected for an additional free-standing fig, F. yoponensis (subgenus Pharmacosycea), and two species of strangler figs, F. citrifolia and F. obtusifolia (subgenus Urostigma) sampled in Panama. All four species displayed significant SGS (mean Sp = 0.014 ± 0.012). Model simulations indicated that most pollination events likely occur at distances > > 1 km, largely ruling out spatially limited pollen dispersal as the determinant of SGS in F. insipida and, by extension, the other fig species. Our results are consistent with the view that Ficus develops fine-scale SGS primarily as a result of localized seed dispersal and/or clumped seedling establishment despite extensive long-distance pollen dispersal. We discuss several ecological and life history factors that could have species- or subgenus-specific impacts on the genetic structure of Neotropical figs. PMID:26226482

  3. Spatial Scales of Genetic Structure in Free-Standing and Strangler Figs (Ficus, Moraceae) Inhabiting Neotropical Forests

    PubMed Central

    Heer, Katrin; Albrecht, Larissa; García-Villacorta, Roosevelt; Staeps, Felix C.; Herre, Edward Allen; Dick, Christopher W.

    2015-01-01

    Wind-borne pollinating wasps (Agaonidae) can transport fig (Ficus sp., Moraceae) pollen over enormous distances (> 100 km). Because of their extensive breeding areas, Neotropical figs are expected to exhibit weak patterns of genetic structure at local and regional scales. We evaluated genetic structure at the regional to continental scale (Panama, Costa Rica, and Peru) for the free-standing fig species Ficus insipida. Genetic differentiation was detected only at distances > 300 km (Jost´s Dest = 0.68 ± 0.07 & FST = 0.30 ± 0.03 between Mesoamerican and Amazonian sites) and evidence for phylogeographic structure (RST>>permuted RST) was only significant in comparisons between Central and South America. Further, we assessed local scale spatial genetic structure (SGS, d ≤ 8 km) in Panama and developed an agent-based model parameterized with data from F. insipida to estimate minimum pollination distances, which determine the contribution of pollen dispersal on SGS. The local scale data for F. insipida was compared to SGS data collected for an additional free-standing fig, F. yoponensis (subgenus Pharmacosycea), and two species of strangler figs, F. citrifolia and F. obtusifolia (subgenus Urostigma) sampled in Panama. All four species displayed significant SGS (mean Sp = 0.014 ± 0.012). Model simulations indicated that most pollination events likely occur at distances > > 1 km, largely ruling out spatially limited pollen dispersal as the determinant of SGS in F. insipida and, by extension, the other fig species. Our results are consistent with the view that Ficus develops fine-scale SGS primarily as a result of localized seed dispersal and/or clumped seedling establishment despite extensive long-distance pollen dispersal. We discuss several ecological and life history factors that could have species- or subgenus-specific impacts on the genetic structure of Neotropical figs. PMID:26226482

  4. The fiber-optic imaging and manipulation of neural activity during animal behavior.

    PubMed

    Miyamoto, Daisuke; Murayama, Masanori

    2016-02-01

    Recent progress with optogenetic probes for imaging and manipulating neural activity has further increased the relevance of fiber-optic systems for neural circuitry research. Optical fibers, which bi-directionally transmit light between separate sites (even at a distance of several meters), can be used for either optical imaging or manipulating neural activity relevant to behavioral circuitry mechanisms. The method's flexibility and the specifications of the light structure are well suited for following the behavior of freely moving animals. Furthermore, thin optical fibers allow researchers to monitor neural activity from not only the cortical surface but also deep brain regions, including the hippocampus and amygdala. Such regions are difficult to target with two-photon microscopes. Optogenetic manipulation of neural activity with an optical fiber has the advantage of being selective for both cell-types and projections as compared to conventional electrophysiological brain tissue stimulation. It is difficult to extract any data regarding changes in neural activity solely from a fiber-optic manipulation device; however, the readout of data is made possible by combining manipulation with electrophysiological recording, or the simultaneous application of optical imaging and manipulation using a bundle-fiber. The present review introduces recent progress in fiber-optic imaging and manipulation methods, while also discussing fiber-optic system designs that are suitable for a given experimental protocol. PMID:26427958

  5. Tracking molecular dynamics without tracking: image correlation of photo-activation microscopy

    NASA Astrophysics Data System (ADS)

    Pandžić, Elvis; Rossy, Jérémie; Gaus, Katharina

    2015-03-01

    Measuring protein dynamics in the plasma membrane can provide insights into the mechanisms of receptor signaling and other cellular functions. To quantify protein dynamics on the single molecule level over the entire cell surface, sophisticated approaches such as single particle tracking (SPT), photo-activation localization microscopy (PALM) and fluctuation-based analysis have been developed. However, analyzing molecular dynamics of fluorescent particles with intermittent excitation and low signal-to-noise ratio present at high densities has remained a challenge. We overcame this problem by applying spatio-temporal image correlation spectroscopy (STICS) analysis to photo-activated (PA) microscopy time series. In order to determine under which imaging conditions this approach is valid, we simulated PA images of diffusing particles in a homogeneous environment and varied photo-activation, reversible blinking and irreversible photo-bleaching rates. Further, we simulated data with high particle densities that populated mobile objects (such as adhesions and vesicles) that often interfere with STICS and fluctuation-based analysis. We demonstrated in experimental measurements that the diffusion coefficient of the epidermal growth factor receptor (EGFR) fused to PAGFP in live COS-7 cells can be determined in the plasma membrane and revealed differences in the time-dependent diffusion maps between wild-type and mutant Lck in activated T cells. In summary, we have developed a new analysis approach for live cell photo-activation microscopy data based on image correlation spectroscopy to quantify the spatio-temporal dynamics of single proteins.

  6. Assessment of Activity of Crohn Disease by Diffusion-Weighted Magnetic Resonance Imaging.

    PubMed

    Li, Xue-Hua; Sun, Can-Hui; Mao, Ren; Zhang, Zhong-Wei; Jiang, Xiao-Song; Pui, Margaret H; Chen, Min-Hu; Li, Zi-Ping

    2015-10-01

    To assess the diagnostic efficacy of diffusion-weighted MR imaging (DWI) for evaluating inflammatory activity in patients with Crohn's disease (CD). A total of 47 CD patients underwent MR enterography (MRE) and DWI using 3 b values of 50, 400, and 800 s/mm. Apparent diffusion coefficients (ADCs) of inflamed and normal bowel wall were calculated. The conventional MRE findings and DWI signal intensities were qualitatively scored from 0 to 3. The correlation between Crohn disease activity index (CDAI) and both ADCs and magnetic resonance imaging scores was analyzed. Receiver-operating characteristic curve analysis was used to determine the diagnostic accuracy of CD activity. Of the 47 patients, 25 were active CD (CDAI≥150) and 22 were inactive (CDAI<150). Diffusion-weighted MR imaging and MRE + DWI scores of active CD were significantly higher than that of inactive CD (both P < 0.001). Apparent diffusion coefficients in inflamed segments of active CD were lower than that of inactive CD (P < 0.001). The DWI scores (r = 0.74, P < 0.001), ADCs (r = -0.71, P < 0.001), MRE scores (r = 0.54, P < 0.001), and MRE + DWI scores (r = 0.66, P < 0.001) were all correlated with CDAI. The areas under the receiver-operating characteristics curves for ADCs, DWI scores, MRE scores, and MRE + DWI scores ranged from 0.83 to 0.98. The threshold ADC value of 1.17 × 10 mm/s allowed differentiation of active from inactive CD with 100% sensitivity and 88% specificity. Diffusion-weighted MR imaging and ADC correlated with CD activity, and had excellent diagnostic accuracy for differentiating active from inactive CD. PMID:26512584

  7. Automatic Tracking of Active Regions and Detection of Solar Flares in Solar EUV Images

    NASA Astrophysics Data System (ADS)

    Caballero, C.; Aranda, M. C.

    2014-05-01

    Solar catalogs are frequently handmade by experts using a manual approach or semi-automated approach. The appearance of new tools is very useful because the work is automated. Nowadays it is impossible to produce solar catalogs using these methods, because of the emergence of new spacecraft that provide a huge amount of information. In this article an automated system for detecting and tracking active regions and solar flares throughout their evolution using the Extreme UV Imaging Telescope (EIT) on the Solar and Heliospheric Observatory (SOHO) spacecraft is presented. The system is quite complex and consists of different phases: i) acquisition and preprocessing; ii) segmentation of regions of interest; iii) clustering of these regions to form candidate active regions which can become active regions; iv) tracking of active regions; v) detection of solar flares. This article describes all phases, but focuses on the phases of tracking and detection of active regions and solar flares. The system relies on consecutive solar images using a rotation law to track the active regions. Also, graphs of the evolution of a region and solar evolution are presented to detect solar flares. The procedure developed has been tested on 3500 full-disk solar images (corresponding to 35 days) taken from the spacecraft. More than 75 % of the active regions are tracked and more than 85 % of the solar flares are detected.

  8. Active self-calibration of thoracoscopic images for assisted minimally invasive spinal surgery

    NASA Astrophysics Data System (ADS)

    Girard, Fantin; Benboujja, Fouzi; Parent, Stefan; Cheriet, Farida

    2010-02-01

    Registration of thoracoscopic images to a preoperative 3D model of the spine is a prerequisite for minimally invasive surgical guidance. We propose an active self-calibration method of thoracoscopic image sequences acquired by an angled monocular endoscope with varying focal length during minimally invasive surgery of the spine. The extrinsic parameters are updated in real time by a motion tracking system while the intrinsic parameters are determined from a set of geometrical primitives extracted from the image of the surgical instrument tracked throughout the thoracoscopic sequence. A particle filter was used for the tracking of the instrument on the image sequence that was preprocessed to detect and correct reflexions due to the light source. The proposed method requires undertaking a pure rotation of the endoscope to update the focal length and exploits the inherent temporal rigid motion of the instrument through consecutive frames. A pure rotation is achievable by undertaking a rotation of the scope cylinder with respect to the head of the camera. Therefore, the surgeon may take full advantage of an angled endoscope by adjusting focus and zoom during surgery. Simulation experiments have assessed the accuracy of the obtained parameters and the optimal number of geometrical primitives required for an active self-calibration of the angled monocular endoscope. Finally, an in vitro experiment demonstrated that 3D reconstruction of rigid structures tracked throughout a monocular thoracoscopic image sequence is feasible and its accuracy is adequate for the registration of thoracoscopic images to a preoperative MRI 3D model of the spine.

  9. Infrared-active quadruple contrast FePt nanoparticles for multiple scale molecular imaging.

    PubMed

    Chou, Shang-Wei; Liu, Chien-Liang; Liu, Tzu-Ming; Shen, Yu-Fang; Kuo, Lun-Chang; Wu, Cheng-Ham; Hsieh, Tsung-Yuan; Wu, Pei-Chun; Tsai, Ming-Rung; Yang, Che-Chang; Chang, Kai-Yao; Lu, Meng-Hua; Li, Pai-Chi; Chen, Shi-Ping; Wang, Yu-Hsin; Lu, Chen-Wen; Chen, Yi-An; Huang, Chih-Chia; Wang, Churng-Ren Chris; Hsiao, Jong-Kai; Li, Meng-Lin; Chou, Pi-Tai

    2016-04-01

    A single nanomaterial with multiple imaging contrasts and functions is highly desired for multiscale theragnosis. Herein, we demonstrate single 1-1.9 μm infrared-active FePt alloy nanoparticles (FePt NPs) offering unprecedented four-contrast-in-one molecular imaging - computed tomography (CT), magnetic resonance imaging (MRI), photoacoustic (PA) imaging, and high-order multiphoton luminescence (HOMPL) microscopy. The PA response of FePt NPs outperforms that of infrared-active gold nanorods by 3- to 5.6-fold under identical excitation fluence and particle concentrations. HOMPL (680 nm) of an isolated FePt NP renders spatial full-width-at-half-maximum values of 432 nm and 300 nm beyond the optical diffraction limit for 1230-nm and 920-nm excitation, respectively. The in vivo targeting function was successfully visualized using HOMPL, PA imaging, CT, and MRI, thereby validating FePt as a single nanomaterial system covering up to four types (Optical/PA/CT/MRI) of molecular imaging contrast, ranging from the microscopic level to whole-body scale investigation. PMID:26854391

  10. Voltage-sensitive dye imaging of primary motor cortex activity produced by ventral tegmental area stimulation.

    PubMed

    Kunori, Nobuo; Kajiwara, Riichi; Takashima, Ichiro

    2014-06-25

    The primary motor cortex (M1) receives dopaminergic projections from the ventral tegmental area (VTA) through the mesocortical dopamine pathway. However, few studies have focused on changes in M1 neuronal activity caused by VTA activation. To address this issue, we used voltage-sensitive dye imaging (VSD) to reveal the spatiotemporal dynamics of M1 activity induced by single-pulse stimulation of VTA in anesthetized rats. VSD imaging showed that brief electrical stimulation of unilateral VTA elicited a short-latency excitatory-inhibitory sequence of neuronal activity not only in the ipsilateral but also in the contralateral M1. The contralateral M1 response was not affected by pharmacological blockade of ipsilateral M1 activity, but it was completely abolished by corpus callosum transection. Although the VTA-evoked neuronal activity extended throughout the entire M1, we found the most prominent activity in the forelimb area of M1. The 6-OHDA-lesioned VTA failed to evoke M1 activity. Furthermore, both excitatory and inhibitory intact VTA-induced activity was entirely extinguished by blocking glutamate receptors in the target M1. When intracortical microstimulation of M1 was paired with VTA stimulation, the evoked forelimb muscle activity was facilitated or inhibited, depending on the interval between the two stimuli. These findings suggest that VTA neurons directly modulate the excitability of M1 neurons via fast glutamate signaling and, consequently, may control the last cortical stage of motor command processing. PMID:24966388

  11. Cerebral activation focusing on strong tasting food: a functional magnetic resonance imaging study.

    PubMed

    Kikuchi, Senichiro; Kubota, Fumio; Nisijima, Koichi; Washiya, Sumio; Kato, Satoshi

    2005-02-28

    Very little research has been conducted on taste imagery because of the difficulty of doing so. We conducted a functional magnetic resonance imaging study to observe cerebral activation patterns produced in volunteers concentrating on pickled plums (umeboshi), a traditional Japanese food with a strong and sour taste. Activation was observed in the right insula, the bilateral opercula, the bilateral orbitofrontal cortices and the left Broca's area. Activation in the insula (primary gustatory area) was very weak and limited to one side. The activation pattern was similar to that of taste perception. Our results showed that it is possible for humans to imagine tastes. PMID:15706236

  12. Calcium imaging of sleep–wake related neuronal activity in the dorsal pons

    PubMed Central

    Cox, Julia; Pinto, Lucas; Dan, Yang

    2016-01-01

    The dorsal pons has long been implicated in the generation of rapid eye movement (REM) sleep, but the underlying circuit mechanisms remain poorly understood. Using cell-type-specific microendoscopic Ca2+ imaging in and near the laterodorsal tegmental nucleus, we found that many glutamatergic neurons are maximally active during REM sleep (REM-max), while the majority of GABAergic neurons are maximally active during wakefulness (wake-max). Furthermore, the activity of glutamatergic neurons exhibits a medio-lateral spatial gradient, with medially located neurons more selectively active during REM sleep. PMID:26911837

  13. The role of lung imaging in pulmonary embolism

    PubMed Central

    Mishkin, Fred S.; Johnson, Philip M.

    1973-01-01

    The advantages of lung scanning in suspected pulmonary embolism are its diagnostic sensitivity, simplicity and safety. The ability to delineate regional pulmonary ischaemia, to quantitate its extent and to follow its response to therapy provides valuable clinical data available by no other simple means. The negative scan effectively excludes pulmonary embolism but, although certain of its features favour the diagnosis of embolism, the positive scan inherently lacks specificity and requires angiographic confirmation when embolectomy, caval plication or infusion of a thrombolytic agent are contemplated. The addition of simple ventilation imaging techniques with radioxenon overcomes this limitation by providing accurate analog estimation or digital quantitation of regional ventilation: perfusion (V/Q) ratios fundamental to understanding the pathophysiologic consequences of embolism and other diseases of the lung. ImagesFig. 1Fig. 2Fig. 3Fig. 4Fig. 5Fig. 6Fig. 7p495-bFig. 8Fig. 9Fig. 10Fig. 11Fig. 12Fig. 13 PMID:4602128

  14. Rapid eye movement-related brain activation in human sleep: a functional magnetic resonance imaging study.

    PubMed

    Wehrle, Renate; Czisch, Michael; Kaufmann, Christian; Wetter, Thomas C; Holsboer, Florian; Auer, Dorothee P; Pollmächer, Thomas

    2005-05-31

    In animal models, ponto-geniculo-occipital waves appear as an early sign of rapid eye movement sleep and may be functionally significant for brain plasticity processes. In this pilot study, we use a combined polysomnographic and functional magnetic resonance imaging approach, and show distinct magnetic resonance imaging signal increases in the posterior thalamus and occipital cortex in close temporal relationship to rapid eye movements during human rapid eye movement sleep. These findings are consistent with cell recordings in animal experiments and demonstrate that functional magnetic resonance imaging can be utilized to detect ponto-geniculo-occipital-like activity in humans. Studying intact neuronal networks underlying sleep regulation is no longer confined to animal models, but has been shown to be feasible in humans by a combined functional magnetic resonance imaging and electroencephalograph approach. PMID:15891584

  15. Space-based laser active imaging simulation system based on HLA

    NASA Astrophysics Data System (ADS)

    Han, Yi; Sun, Huayan; Li, Yingchun

    2013-09-01

    This paper adopts the High Level Architecture to develop the space-based laser active imaging distribution simulation software system, and designs the system framework which contains three-step workflow including modeling, experimental and analysis. The paper puts forward the general needs of the simulation system first, then builds the simulation system architecture based on HLA and constructs 7 simulation federal members. The simulation system has the primary functions of space target scattering characteristic analysis, imaging simulation, image processing and target recognition, and system performance analysis and so on, and can support the whole simulation process. The results show that the distribution simulation system can meet the technical requirements of the space-based laser imaging simulation.

  16. Segmentation of Bone with Region Based Active Contour Model in PD Weighted MR Images of Shoulder.

    PubMed

    Sezer, Aysun; Sezer, Hasan Basri; Albayrak, Songul

    2015-01-01

    Proton density (PD) weighted MR images present inhomogeneity problem, low signal to noise ratio (SNR) and cannot define bone borders clearly. Segmentation of PD weighted images is hampered with these properties of PD weighted images which even limit the visual inspection. The purpose of this study is to determine the effectiveness of segmentation of humeral head from axial PD MR images with active contour without edge (ACWE) model. We included 219 images from our original data set. We extended the use of speckle reducing anisotropic diffusion (SRAD) in PD MR images by estimation of standard deviation of noise (SDN) from ROI. To overcome the problem of initialization of the initial contour of these region based methods, the location of the initial contour was automatically determined with use of circular Hough transform. For comparison, signed pressure force (SPF), fuzzy C-means, and Gaussian mixture models were applied and segmentation results of all four methods were also compared with the manual segmentation results of an expert. Experimental results on our own database show promising results. This is the first study in the literature to segment normal and pathological humeral heads from PD weighted MR images. PMID:26064185

  17. Skin sympathetic nerve activity in humans during exposure to emotionally-charged images: sex differences.

    PubMed

    Brown, Rachael; Macefield, Vaughan G

    2014-01-01

    While it is known that anxiety or emotional arousal affects skin sympathetic nerve activity (SSNA), the galvanic skin response (GSR) is the most widely used parameter to infer increases in SSNA during stress or emotional studies. We recently showed that SSNA provides a more sensitive measure of emotional state than effector-organ responses. The aim of the present study was to assess whether there are gender differences in the responses of SSNA and other physiological parameters such as blood pressure, heart rate, skin blood flow and sweat release, while subjects viewed neutral or emotionally-charged images from the International Affective Picture System (IAPS). Changes in SSNA were assessed using microneurography in 20 subjects (10 male and 10 female). Blocks of positively-charged (erotica) or negatively-charge images (mutilation) were presented in a quasi-random fashion, following a block of neutral images, with each block containing 15 images and lasting 2 min. Images of both erotica and mutilation caused significant increases in SSNA, with increases being greater for males viewing erotica and greater for females viewing mutilation. The increases in SSNA were often coupled with sweat release and cutaneous vasoconstriction; however, these markers were not significantly different than those produced by viewing neutral images and were not always consistent with the SSNA increases. We conclude that SSNA increases with both positively-charged and negatively-charged emotional images, yet sex differences are present. PMID:24678303

  18. DETECTING ACTIVE GALACTIC NUCLEI USING MULTI-FILTER IMAGING DATA. II. INCORPORATING ARTIFICIAL NEURAL NETWORKS

    SciTech Connect

    Dong, X. Y.; De Robertis, M. M.

    2013-10-01

    This is the second paper of the series Detecting Active Galactic Nuclei Using Multi-filter Imaging Data. In this paper we review shapelets, an image manipulation algorithm, which we employ to adjust the point-spread function (PSF) of galaxy images. This technique is used to ensure the image in each filter has the same and sharpest PSF, which is the preferred condition for detecting AGNs using multi-filter imaging data as we demonstrated in Paper I of this series. We apply shapelets on Canada-France-Hawaii Telescope Legacy Survey Wide Survey ugriz images. Photometric parameters such as effective radii, integrated fluxes within certain radii, and color gradients are measured on the shapelets-reconstructed images. These parameters are used by artificial neural networks (ANNs) which yield: photometric redshift with an rms of 0.026 and a regression R-value of 0.92; galaxy morphological types with an uncertainty less than 2 T types for z ≤ 0.1; and identification of galaxies as AGNs with 70% confidence, star-forming/starburst (SF/SB) galaxies with 90% confidence, and passive galaxies with 70% confidence for z ≤ 0.1. The incorporation of ANNs provides a more reliable technique for identifying AGN or SF/SB candidates, which could be very useful for large-scale multi-filter optical surveys that also include a modest set of spectroscopic data sufficient to train neural networks.

  19. The determination of the antiperspirant activity of aluminium-chlorhydrate by digital image-analysis.

    PubMed

    Sauermann, G; Hoppe, U; Kligman, A M

    1992-02-01

    Synopsis The method of Minor to visualize by iodine-starch-reaction the activity of sweat glands was used in combination with image-analysis to quantify sweat-secretion. Aqueous aluminium chlorohydrate solutions (ACH) (1, 2, 4, 8, 16%) were applied twice daily for 6 days to defined areas of the lower volar forearms. After 3 and 6 days of treatment perspiration was induced by thermal stress. The dark blue spots on top of active glands which are formed by iodine-starch-complexes were counted and their projection area was measured by an image analysing system. Increasing concentrations of ACH lower the number of active sweat glands, while the size of the dark spots is not dependent on the concentration of the active ingredient. PMID:19272092

  20. Dual-reporter in vivo imaging of transient and inducible heat-shock promoter activation.

    PubMed

    Fortin, Pierre-Yves; Genevois, Coralie; Chapolard, Mathilde; Santalucía, Tomàs; Planas, Anna M; Couillaud, Franck

    2014-02-01

    Gene promoter activity can be studied in vivo by molecular imaging methods using reporter gene technology. Transcription of the reporter and the reported genes occurs simultaneously. However, imaging depends on reporter protein translation, stability, and cellular fate that may differ among the various proteins. A double transgenic mouse strain expressing the firefly luciferase (lucF) and fluorescent mPlum protein under the transcriptional control of the thermo-inducible heat-shock protein (Hspa1b) promoter was generated allowing to follow up the reporter proteins by different and complementary in vivo imaging technologies. These mice were used for in vivo imaging by bioluminescence and epi fluorescence reflectance imaging (BLI & FRI) and as a source of embryonic fibroblast (MEF) for in vitro approaches. LucF, mPlum and endogenous Hsp70 mRNAs were transcribed simultaneously. The increase in mRNA was transient, peaking at 3 h and then returning to the basal level about 6 h after the thermal stimulations. The bioluminescent signal was transient and initiated with a 3 h delay versus mRNA expression. The onset of mPlum fluorescence was more delayed, increasing slowly up to 30 h after heat-shock and remaining for several days. This mouse allows for both bioluminescence imaging (BLI) and fluorescence reflectance imaging (FRI) of Hsp70 promoter activation showing an early and transient lucF activity and a retrospective and persistent mPlum fluorescence. This transgenic mouse will allow following the transient local induction of Hsp-70 promoter beyond its induction time-frame and relate into subsequent dynamic biological effects of the heat-shock response. PMID:24575340

  1. Dual-reporter in vivo imaging of transient and inducible heat-shock promoter activation

    PubMed Central

    Fortin, Pierre-Yves; Genevois, Coralie; Chapolard, Mathilde; Santalucía, Tomàs; Planas, Anna M.; Couillaud, Franck

    2014-01-01

    Gene promoter activity can be studied in vivo by molecular imaging methods using reporter gene technology. Transcription of the reporter and the reported genes occurs simultaneously. However, imaging depends on reporter protein translation, stability, and cellular fate that may differ among the various proteins. A double transgenic mouse strain expressing the firefly luciferase (lucF) and fluorescent mPlum protein under the transcriptional control of the thermo-inducible heat-shock protein (Hspa1b) promoter was generated allowing to follow up the reporter proteins by different and complementary in vivo imaging technologies. These mice were used for in vivo imaging by bioluminescence and epi fluorescence reflectance imaging (BLI & FRI) and as a source of embryonic fibroblast (MEF) for in vitro approaches. LucF, mPlum and endogenous Hsp70 mRNAs were transcribed simultaneously. The increase in mRNA was transient, peaking at 3 h and then returning to the basal level about 6 h after the thermal stimulations. The bioluminescent signal was transient and initiated with a 3 h delay versus mRNA expression. The onset of mPlum fluorescence was more delayed, increasing slowly up to 30 h after heat-shock and remaining for several days. This mouse allows for both bioluminescence imaging (BLI) and fluorescence reflectance imaging (FRI) of Hsp70 promoter activation showing an early and transient lucF activity and a retrospective and persistent mPlum fluorescence. This transgenic mouse will allow following the transient local induction of Hsp-70 promoter beyond its induction time-frame and relate into subsequent dynamic biological effects of the heat-shock response. PMID:24575340

  2. Acute two-photon imaging of the neurovascular unit in the cortex of active mice

    PubMed Central

    Tran, Cam Ha T.; Gordon, Grant R.

    2015-01-01

    In vivo two-photon scanning fluorescence imaging is a powerful technique to observe physiological processes from the millimeter to the micron scale in the intact animal. In neuroscience research, a common approach is to install an acute cranial window and head bar to explore neocortical function under anesthesia before inflammation peaks from the surgery. However, there are few detailed acute protocols for head-restrained and fully awake animal imaging of the neurovascular unit during activity. This is because acutely performed awake experiments are typically untenable when the animal is naïve to the imaging apparatus. Here we detail a method that achieves acute, deep-tissue two-photon imaging of neocortical astrocytes and microvasculature in behaving mice. A week prior to experimentation, implantation of the head bar alone allows mice to train for head-immobilization on an easy-to-learn air-supported ball treadmill. Following just two brief familiarization sessions to the treadmill on separate days, an acute cranial window can subsequently be installed for immediate imaging. We demonstrate how running and whisking data can be captured simultaneously with two-photon fluorescence signals with acceptable movement artifacts during active motion. We also show possible applications of this technique by (1) monitoring dynamic changes to microvascular diameter and red blood cells in response to vibrissa sensory stimulation, (2) examining responses of the cerebral microcirculation to the systemic delivery of pharmacological agents using a tail artery cannula during awake imaging, and (3) measuring Ca2+ signals from synthetic and genetically encoded Ca2+ indicators in astrocytes. This method will facilitate acute two-photon fluorescence imaging in awake, active mice and help link cellular events within the neurovascular unit to behavior. PMID:25698926

  3. Visually evoked activity in cortical cells imaged in freely moving animals

    PubMed Central

    Sawinski, Juergen; Wallace, Damian J.; Greenberg, David S.; Grossmann, Silvie; Denk, Winfried; Kerr, Jason N. D.

    2009-01-01

    We describe a miniaturized head-mounted multiphoton microscope and its use for recording Ca2+ transients from the somata of layer 2/3 neurons in the visual cortex of awake, freely moving rats. Images contained up to 20 neurons and were stable enough to record continuously for >5 min per trial and 20 trials per imaging session, even as the animal was running at velocities of up to 0.6 m/s. Neuronal Ca2+ transients were readily detected, and responses to various static visual stimuli were observed during free movement on a running track. Neuronal activity was sparse and increased when the animal swept its gaze across a visual stimulus. Neurons showing preferential activation by specific stimuli were observed in freely moving animals. These results demonstrate that the multiphoton fiberscope is suitable for functional imaging in awake and freely moving animals. PMID:19889973

  4. Functional imaging of glucose-evoked rat islet activities using transient intrinsic optical signals

    NASA Astrophysics Data System (ADS)

    Yao, Xin-Cheng; Cui, Wan-Xing; Li, Yi-Chao; Zhang, Wei; Lu, Rong-Wen; Thompson, Anthony; Amthor, Franklin; Wang, Xu-Jing

    2012-05-01

    We demonstrate intrinsic optical signal (IOS) imaging of intact rat islet, which consists of many endocrine cells working together. A near-infrared digital microscope was employed for optical monitoring of islet activities evoked by glucose stimulation. Dynamic NIR images revealed transient IOS responses in the islet activated by low-dose (2.75 mM) and high-dose (5.5 mM) glucose stimuli. Comparative experiments and quantitative analysis indicated that both glucose metabolism and calcium/insulin dynamics might contribute to the observed IOS responses. Further investigation of the IOS imaging technology may provide a high resolution method for ex vivo functional examination of the islet, which is important for advanced study of diabetes associated islet dysfunctions and for improved quality control of donor islets for transplantation.

  5. Serial Magnetic Resonance Imaging in Active Surveillance of Prostate Cancer: Incremental Value

    PubMed Central

    Felker, Ely R.; Wu, Jason; Natarajan, Shyam; Margolis, Daniel J.; Raman, Steven S.; Huang, Jiaoti; Dorey, Fred; Marks, Leonard S.

    2016-01-01

    Purpose We assessed whether changes in serial multiparametric magnetic resonance imaging can help predict the pathological progression of prostate cancer in men on active surveillance. Materials and Methods A retrospective cohort study was conducted of 49 consecutive men with Gleason 6 prostate cancer who underwent multi-parametric magnetic resonance imaging at baseline and again more than 6 months later, each followed by a targeted prostate biopsy, between January 2011 and May 2015. We evaluated whether progression on multiparametric magnetic resonance imaging (an increase in index lesion suspicion score, increase in index lesion volume or decrease in index lesion apparent diffusion coefficient) could predict pathological progression (Gleason 3 + 4 or greater on subsequent biopsy, in systematic or targeted cores). Diagnostic performance of multiparametric magnetic resonance imaging was determined with and without clinical data using a binary logistic regression model. Results The mean interval between baseline and followup multiparametric magnetic resonance imaging was 28.3 months (range 11 to 43). Pathological progression occurred in 19 patients (39%). The sensitivity, specificity, positive predictive value and negative predictive value of multiparametric magnetic resonance imaging was 37%, 90%, 69% and 70%, respectively. Area under the receiver operating characteristic curve was 0.63. A logistic regression model using clinical information (maximum cancer core length greater than 3 mm on baseline biopsy or a prostate specific antigen density greater than 0.15 ng/ml2 at followup biopsy) had an AUC of 0.87 for predicting pathological progression. The addition of serial multiparametric magnetic resonance imaging data significantly improved the AUC to 0.91 (p = 0.044). Conclusions Serial multiparametric magnetic resonance imaging adds incremental value to prostate specific antigen density and baseline cancer core length for predicting Gleason 6 upgrading in men on

  6. MR Imaging of Myeloperoxidase Activity in a Model of the Inflamed Aneurysm Wall

    PubMed Central

    Gounis, M.J.; van der Bom, I.M.J.; Wakhloo, A.K.; Zheng, S.; Chueh, J.-Y.; Kühn, A.L.; Bogdanov, A.A.

    2014-01-01

    Background and Purpose Although myeloperoxidase (MPO) activity in vivo can be visualized using non-invasive imaging, successful clinical translation requires further optimization of the imaging approach. We report a motion-sensitized-driven-equilibrium (MSDE) for the detection of an MPO activity-specific gadolinium (Gd)-containing imaging agent (IA) in experimental aneurysm models that compensates for irregular blood flow enabling vascular wall imaging in the aneurysm. Materials and Methods We deployed a phantom model to optimize a MSDE MR sequence that suppresses complex flow patterns within the aneurysm for detection of an MPO-specific Gd-chelate. The phantom was built from rotational angiography of a rabbit elastase aneurysm model and connected to a cardiac pulse duplicator mimicking rabbit-specific flow conditions. Thereafter, we further refined the MSDE sequence and applied it in vivo to rabbit aneurysm models with and without inflammation in the aneurysmal wall. Under each condition, the aneurysms were imaged before and after intravenous administration of the IA. The signal-to-noise ratio (SNR) of each MR slice through the aneurysm was calculated. Results The MSDE sequence was optimized to reduce flow signal enabling detection of the MPO-IA in the phantom. The optimized imaging protocol in the rabbit model of saccular aneurysms revealed a significant increase in the change of SNR pre- to postcontrast MR signal intensities in the inflamed aneurysms as compared to naïve aneurysms and the adjacent carotid artery (p<0.0001). Conclusion A diagnostic MR protocol was optimized for molecular imaging of an MPO-specific molecular imaging agent in an animal model of brain aneurysms. PMID:25273534

  7. Structured Activities in Perceptual Training to Aid Retention of Visual and Auditory Images.

    ERIC Educational Resources Information Center

    Graves, James W.; And Others

    The experimental program in structured activities in perceptual training was said to have two main objectives: to train children in retention of visual and auditory images and to increase the children's motivation to learn. Eight boys and girls participated in the program for two hours daily for a 10-week period. The age range was 7.0 to 12.10…

  8. Croconaine rotaxane for acid activated photothermal heating and ratiometric photoacoustic imaging of acidic pH.

    PubMed

    Guha, Samit; Shaw, Gillian Karen; Mitcham, Trevor M; Bouchard, Richard R; Smith, Bradley D

    2016-01-01

    Absorption of 808 nm laser light by liposomes containing a pH sensitive, near-infrared croconaine rotaxane dye increases dramatically in weak acid. A stealth liposome composition permits acid activated, photothermal heating and also acts as an effective nanoparticle probe for ratiometric photoacoustic imaging of acidic pH in deep sample locations, including a living mouse. PMID:26502996

  9. Brain Activation during Semantic Processing in Autism Spectrum Disorders via Functional Magnetic Resonance Imaging

    ERIC Educational Resources Information Center

    Harris, Gordon J.; Chabris, Christopher F.; Clark, Jill; Urban, Trinity; Aharon, Itzhak; Steele, Shelley; McGrath, Lauren; Condouris, Karen; Tager-Flusberg, Helen

    2006-01-01

    Language and communication deficits are core features of autism spectrum disorders (ASD), even in high-functioning adults with ASD. This study investigated brain activation patterns using functional magnetic resonance imaging in right-handed adult males with ASD and a control group, matched on age, handedness, and verbal IQ. Semantic processing in…

  10. In Vivo Mesoscopic Voltage-Sensitive Dye Imaging of Brain Activation

    NASA Astrophysics Data System (ADS)

    Tang, Qinggong; Tsytsarev, Vassiliy; Frank, Aaron; Wu, Yalun; Chen, Chao-Wei; Erzurumlu, Reha S.; Chen, Yu

    2016-04-01

    Functional mapping of brain activity is important in elucidating how neural networks operate in the living brain. The whisker sensory system of rodents is an excellent model to study peripherally evoked neural activity in the central nervous system. Each facial whisker is represented by discrete modules of neurons all along the pathway leading to the neocortex. These modules are called “barrels” in layer 4 of the primary somatosensory cortex. Their location (approximately 300–500 μm below cortical surface) allows for convenient imaging of whisker-evoked neural activity in vivo. Fluorescence laminar optical tomography (FLOT) provides depth-resolved fluorescence molecular information with an imaging depth of a few millimeters. Angled illumination and detection configurations can improve both resolution and penetration depth. We applied angled FLOT (aFLOT) to record 3D neural activities evoked in the whisker system of mice by deflection of a single whisker in vivo. A 100 μm capillary and a pair of microelectrodes were inserted to the mouse brain to test the capability of the imaging system. The results show that it is possible to obtain 3D functional maps of the sensory periphery in the brain. This approach can be broadly applicable to functional imaging of other brain structures.

  11. In Vivo Mesoscopic Voltage-Sensitive Dye Imaging of Brain Activation

    PubMed Central

    Tang, Qinggong; Tsytsarev, Vassiliy; Frank, Aaron; Wu, Yalun; Chen, Chao-wei; Erzurumlu, Reha S.; Chen, Yu

    2016-01-01

    Functional mapping of brain activity is important in elucidating how neural networks operate in the living brain. The whisker sensory system of rodents is an excellent model to study peripherally evoked neural activity in the central nervous system. Each facial whisker is represented by discrete modules of neurons all along the pathway leading to the neocortex. These modules are called “barrels” in layer 4 of the primary somatosensory cortex. Their location (approximately 300–500 μm below cortical surface) allows for convenient imaging of whisker-evoked neural activity in vivo. Fluorescence laminar optical tomography (FLOT) provides depth-resolved fluorescence molecular information with an imaging depth of a few millimeters. Angled illumination and detection configurations can improve both resolution and penetration depth. We applied angled FLOT (aFLOT) to record 3D neural activities evoked in the whisker system of mice by deflection of a single whisker in vivo. A 100 μm capillary and a pair of microelectrodes were inserted to the mouse brain to test the capability of the imaging system. The results show that it is possible to obtain 3D functional maps of the sensory periphery in the brain. This approach can be broadly applicable to functional imaging of other brain structures. PMID:27125318

  12. Research on acupuncture points and cortical functional activation position in cats by infrared imaging detection

    NASA Astrophysics Data System (ADS)

    Chen, Shuwang; Sha, Zhanyou; Wang, Shuhai; Wen, Huanming

    2007-12-01

    The research of the brain cognition is mainly to find out the activation position in brain according to the stimulation at present in the world. The research regards the animals as the experimental objects and explores the stimulation response on the cerebral cortex of acupuncture. It provides a new method, which can detect the activation position on the creatural cerebral cortex directly by middle-far infrared imaging. According to the theory of local temperature situation, the difference of cortical temperature maybe associate with the excitement of cortical nerve cells, the metabolism of local tissue and the local hemal circulation. Direct naked detection of temperature variety on cerebral cortex is applied by middle and far infrared imaging technology. So the activation position is ascertained. The effect of stimulation response is superior to other indirect methods. After removing the skulls on the head, full of cerebral cortex of a cat are exposed. By observing the infrared images and measuring the temperatures of the visual cerebral cortex during the process of acupuncturing, the points are used to judge the activation position. The variety in the cortical functional sections is corresponding to the result of the acupuncture points in terms of infrared images and temperatures. According to experimental results, we know that the variety of a cortical functional section is corresponding to a special acupuncture point exactly.

  13. Assisting in Radiology/Imaging. Instructor's Guide, Student's Manual, and Student Learning Activities.

    ERIC Educational Resources Information Center

    Fair, Helena J.

    The instructor's guide, the first of three documents in this package, is designed for a course to help students who are investigating the activities within a radiology department or considering any of the imaging technologies as a career. The material is designed to relate training experience to information studied in the classroom. This…

  14. Visual Cortical Gamma-Band Activity During Free Viewing of Natural Images

    PubMed Central

    Brunet, Nicolas; Bosman, Conrado A.; Roberts, Mark; Oostenveld, Robert; Womelsdorf, Thilo; De Weerd, Peter; Fries, Pascal

    2015-01-01

    Gamma-band activity in visual cortex has been implicated in several cognitive operations, like perceptual grouping and attentional selection. So far, it has been studied primarily under well-controlled visual fixation conditions and using well-controlled stimuli, like isolated bars or patches of grating. If gamma-band activity is to subserve its purported functions outside of the laboratory, it should be present during natural viewing conditions. We recorded neuronal activity with a 252-channel electrocorticographic (ECoG) grid covering large parts of the left hemisphere of 2 macaque monkeys, while they freely viewed natural images. We found that natural viewing led to pronounced gamma-band activity in the visual cortex. In area V1, gamma-band activity during natural viewing showed a clear spectral peak indicative of oscillatory activity between 50 and 80 Hz and was highly significant for each of 65 natural images. Across the ECoG grid, gamma-band activity during natural viewing was present over most of the recorded visual cortex and absent over most remaining cortex. After saccades, the gamma peak frequency slid down to 30–40 Hz at around 80 ms postsaccade, after which the sustained 50- to 80-Hz gamma-band activity resumed. We propose that gamma-band activity plays an important role during natural viewing. PMID:24108806

  15. Versatile illumination platform and fast optical switch to give standard observation camera gated active imaging capacity

    NASA Astrophysics Data System (ADS)

    Grasser, R.; Peyronneaudi, Benjamin; Yon, Kevin; Aubry, Marie

    2015-10-01

    CILAS, subsidiary of Airbus Defense and Space, develops, manufactures and sales laser-based optronics equipment for defense and homeland security applications. Part of its activity is related to active systems for threat detection, recognition and identification. Active surveillance and active imaging systems are often required to achieve identification capacity in case for long range observation in adverse conditions. In order to ease the deployment of active imaging systems often complex and expensive, CILAS suggests a new concept. It consists on the association of two apparatus working together. On one side, a patented versatile laser platform enables high peak power laser illumination for long range observation. On the other side, a small camera add-on works as a fast optical switch to select photons with specific time of flight only. The association of the versatile illumination platform and the fast optical switch presents itself as an independent body, so called "flash module", giving to virtually any passive observation systems gated active imaging capacity in NIR and SWIR.

  16. Regulatory mechanisms of ethylene biosynthesis in response to various stimuli during maturation and ripening in fig fruit (Ficus carica L.).

    PubMed

    Owino, W O; Manabe, Y; Mathooko, F M; Kubo, Y; Inaba, A

    2006-01-01

    In order to obtain a greater uniformity of maturation, the growth of the fig fruit (Ficus carica L.) can be stimulated by the application of either olive oil, ethrel/ethephon or auxin. The three treatments induce ethylene production in figs. In this study, we investigated the regulatory mechanisms responsible for oil, auxin and ethylene induced ethylene production in figs. The ethylene production in response to olive oil, auxin, and propylene treatments and during ripening were all induced by 1-methylcyclopropene (1-MCP) and inhibited by propylene indicating a negative feedback regulation mechanism. Three 1-aminocyclopropane-1-carboxylic acid (ACC) synthase genes (Fc-ACS1, Fc-ACS2 and Fc-ACS3) and one ACC oxidase gene (Fc-ACO1) were isolated and their expression patterns in response to either oil, propylene or auxin treatment in figs determined. The expression patterns of Fc-ACS1 and Fc-ACO1 were clearly inhibited by 1-MCP and induced by propylene in oil treated and ripe fruits indicating positive regulation by ethylene, whereas Fc-ACS2 gene expression was induced by 1-MCP and inhibited by propylene indicating negative regulation by ethylene. The Fc-ACS3 mRNA showed high level accumulation in the auxin treated fruit. The inhibition of Fc-ACS3 gene by 1-MCP in oil treated and in ripe fruits suggests that auxin and ethylene modulate the expression of this gene by multi-responsive signal transduction pathway mechanisms. We further report that the olive oil-induced ethylene in figs involves the ACC-dependent pathway and that multiple ethylene regulatory pathways are involved during maturation and ripening in figs and each specific pathway depends on the inducer/stimulus. PMID:16889975

  17. Analysis of noise characteristics for the active pixels in CMOS image sensors for X-ray imaging

    NASA Astrophysics Data System (ADS)

    Kim, Young Soo; Cho, Gyuseong; Bae, Jun-Hyung

    2006-09-01

    CMOS image sensors have poorer performance compared to conventional charge coupled devices (CCDs). Since CMOS Active Pixel Sensors (APSs) in general have higher temporal noise, higher dark current, smaller full well charge capacitance, and lower spectral response, they cannot provide the same wide dynamic range and superior signal to noise ratio as CCDs. In view of electronic noise, the main source for the CMOS APS is the pixel, along with other signal processing blocks such as row and column decoder, analog signal processor (ASP), analog-to-digital converter (ADC), and timing and control logic circuitry. Therefore, it is important and necessary to characterize noise of the active pixels in CMOS APSs, and we performed experimental measurements and comparisons with theoretical estimations. To derive noise source of the pixels, we designed and fabricated four types of CMOS active pixels, and each pixel is composed of a photodiode and three MOS transistors. The size of these pixels is 100 μm×100 μm. The test chip was fabricated using ETRI 0.8 μm (2P/2M) standard CMOS process. It was found that the dominant noise in CMOS active pixels is shot noise during integration under normal operating conditions. And, it was also seen that epitaxial type pixels have similar noise level compared to non-epitaxial type, and the noise of diffusion type pixel is larger than for a well type pixel on the same substrate type.

  18. Three-dimensional functional magnetic resonance imaging of human brain on a clinical 1.5-T scanner.

    PubMed Central

    van Gelderen, P; Ramsey, N F; Liu, G; Duyn, J H; Frank, J A; Weinberger, D R; Moonen, C T

    1995-01-01

    Functional magnetic resonance imaging (fMRI) is a tool for mapping brain function that utilizes neuronal activity-induced changes in blood oxygenation. An efficient three-dimensional fMRI method is presented for imaging brain activity on conventional, widely available, 1.5-T scanners, without additional hardware. This approach uses large magnetic susceptibility weighting based on the echo-shifting principle combined with multiple gradient echoes per excitation. Motor stimulation, induced by self-paced finger tapping, reliably produced significant signal increase in the hand region of the contralateral primary motor cortex in every subject tested. Images Fig. 2 Fig. 3 PMID:7624341

  19. The Stellar Imager (SI) - A Mission to Resolve Stellar Surfaces, Interiors, and Magnetic Activity

    NASA Technical Reports Server (NTRS)

    Carpenter, Kenneth; Schrijver, Carolus J.; Karovska, Margarita

    2007-01-01

    The Stellar Imager (SI) is a UV/Optical, Space-Based Interferometer designed to enable 0.1 milli-arcsecond (mas) spectral imaging of stellar surfaces and, via asteroseismology, stellar interiors and of the Universe in general. The ultra-sharp images of the Stellar Imager will revolutionize our view of many dynamic astrophysical processes by transforming point sources into extended sources, and snapshots into evolving views. SI's science focuses on the role of magnetism in the Universe, particularly on magnetic activity on the surfaces of stars like the Sun. SI's prime goal is to enable long-term forecasting of solar activity and the space weather that it drives. SI will also revolutionize our understanding of the formation of planetary systems, of the habitability and climatology of distant planets, and of many magneto-hydrodynamically controlled processes in the Universe. SI is included as a 'Flagship and Landmark Discovery Mission' in the 2005 NASA Sun Solar System Connection (SSSC) Roadmap and as a candidate for a 'Pathways to Life Observatory' in the NASA Exploration of the Universe Division (EUD) Roadmap (May, 2005). In this paper we discuss the science goals and technology needs of, and the baseline design for, the SI Mission (http://hires.gsfc.nasa.gov/si/) its ability to image the 'Biggest, Baddest, Coolest Stars'.

  20. Interactive Change Detection Using High Resolution Remote Sensing Images Based on Active Learning with Gaussian Processes

    NASA Astrophysics Data System (ADS)

    Ru, Hui; Yu, Huai; Huang, Pingping; Yang, Wen

    2016-06-01

    Although there have been many studies for change detection, the effective and efficient use of high resolution remote sensing images is still a problem. Conventional supervised methods need lots of annotations to classify the land cover categories and detect their changes. Besides, the training set in supervised methods often has lots of redundant samples without any essential information. In this study, we present a method for interactive change detection using high resolution remote sensing images with active learning to overcome the shortages of existing remote sensing image change detection techniques. In our method, there is no annotation of actual land cover category at the beginning. First, we find a certain number of the most representative objects in unsupervised way. Then, we can detect the change areas from multi-temporal high resolution remote sensing images by active learning with Gaussian processes in an interactive way gradually until the detection results do not change notably. The artificial labelling can be reduced substantially, and a desirable detection result can be obtained in a few iterations. The experiments on Geo-Eye1 and WorldView2 remote sensing images demonstrate the effectiveness and efficiency of our proposed method.

  1. Validation of a target acquisition model for active imager using perception experiments

    NASA Astrophysics Data System (ADS)

    Lapaz, Frédéric; Canevet, Loïc

    2007-10-01

    Active night vision systems based on laser diodes emitters have now reached a technology level allowing military applications. In order to predict the performance of observers using such systems, we built an analytic model including sensor, atmosphere, visualization and eye effects. The perception task has been modelled using the Targeting Task Performance metric (TTP metric) developed by R. Vollmerhausen from the Night Vision and Electronic Sensors Directorate (NVESD). Sensor and atmosphere models have been validated separately. In order to validate the whole model, two identification tests have been set up. The first set submitted to trained observers was made of hybrid images. The target to background contrast, the blur and the noise were added to armoured vehicles signatures in accordance to sensor and atmosphere models. The second set of images was made with the same targets, sensed by a real active sensor during field trials. Images were recorded, showing different vehicles, at different ranges and orientations, under different illumination and acquisition configurations. Indeed, this set of real images was built with three different types of gating: wide illumination, illumination of the background and illumination of the target. Analysis of the perception experiments results showed a good concordance between the two sets of images. The calculation of an identification criterion, related to this set of vehicles in the near infrared, gave the same results in both cases. The impact of gating on observer's performance was also evaluated.

  2. Protease-Activated Pore-Forming Peptides for the Treatment and Imaging of Prostate Cancer

    PubMed Central

    LeBeau, Aaron M.; Denmeade, Samuel R.

    2015-01-01

    A common hallmark of cancers with highly aggressive phenotypes is increased proteolysis in the tumor and the surrounding microenvironment. Prostate cancer has a number of proteases uniquely associated with it that may play various important roles in disease progression. In this report, we utilize the peritumoral proteolytic activity of prostate cancer to activate engineered peptide constructs for the treatment and noninvasive imaging of prostate cancer. Using a modular "propeptide" approach, a cationic diastereomeric pore-forming peptide domain was linked to an inactivating acidic peptide domain. The inactivating acidic peptide domain was engineered to be a cleavable substrate for the secreted serine protease prostate-specific antigen (PSA) or the transmembrane metalloprotease prostate-specific membrane antigen (PSMA). The propeptides were then evaluated in a direct comparison study. Both the PSA and PSMA activated propeptides were found to be cytotoxic to prostate cancer cells in vitro. In vivo, however, treatment of LNCaP and CWR22Rv1 xenografts with the PSMA propeptide resulted in a pronounced cytostatic effect when compared with xenografts treated with the PSA propeptide or the cationic diastereomeric peptide alone. The PSMA activated propeptide also proved to be an effective optical imaging probe in vivo when labeled with a near-infrared fluorophore. These data suggest that protease-activated pore-forming peptides could potentially be used for both imaging and treating prostate cancer. PMID:25537662

  3. Optical coherence tomography for cross-sectional imaging of neural activity

    PubMed Central

    Yeh, Yi-Jou; Black, Adam J.; Landowne, David; Akkin, Taner

    2015-01-01

    Abstract. We report a functional optical coherence tomography cross-sectional scanner to detect neural activity using unmyelinated nerves dissected from squid. The nerves, unstained or stained with a voltage-sensitive dye, were imaged in a nerve chamber. Transient phase changes from backscattered light were detected during action potential propagation. The results show that the scanner can provide high spatiotemporal resolution cross-sectional images of neural activity (15  μs/A-line; 0.25  ms/B-scan; ∼8.5×5.5  μm2 in xz). The advantage of this method compared to monitoring a single depth profile z is a dramatic increase in the number of available sites that can be measured in two spatial dimensions xz with lateral scanning; therefore, the study demonstrates that two-dimensional monitoring of small-scale functional activity would also be feasible. PMID:26217674

  4. Comparison of the Extended Kalman Filter and the Unscented Kalman Filter for Magnetocardiography activation time imaging

    NASA Astrophysics Data System (ADS)

    Ahrens, H.; Argin, F.; Klinkenbusch, L.

    2013-07-01

    The non-invasive and radiation-free imaging of the electrical activity of the heart with Electrocardiography (ECG) or Magnetocardiography (MCG) can be helpful for physicians for instance in the localization of the origin of cardiac arrhythmia. In this paper we compare two Kalman Filter algorithms for the solution of a nonlinear state-space model and for the subsequent imaging of the activation/depolarization times of the heart muscle: the Extended Kalman Filter (EKF) and the Unscented Kalman Filter (UKF). The algorithms are compared for simulations of a (6×6) magnetometer array, a torso model with piecewise homogeneous conductivities, 946 current dipoles located in a small part of the heart (apex), and several noise levels. It is found that for all tested noise levels the convergence of the activation times is faster for the UKF.

  5. Incoherent sub-terahertz radiation source with a photomixer array for active imaging in smoky environments

    NASA Astrophysics Data System (ADS)

    Shimizu, Naofumi; Matsuyama, Ken; Uchida, Hidetake

    2015-03-01

    We propose a sub-terahertz (THz) illuminator suitable for use with a THz camera when exploring objects within and behind smoke at the scene of a fire. The illuminator contains a photomixer array and each photomixer generates incoherent sub-THz waves from a single-mode laser light and optical noise using photomixing. The incoherency of the generated sub-THz waves enables us to raise their intensity by increasing the number of photomixers in operation, which makes it possible to realize very bright sub-THz illumination. Consequently, objects being under searched for within or behind smoke can be clearly illuminated using the illuminator and visualized by the THz camera even though they are surrounded by thick and/or high-temperature smoke. To verify our concept, we conducted active imaging with coherent and incoherent sub-THz radiation from a photomixer array utilizing reflection geometry. Although the contrast of the image was improved by increasing number of photomixers in operation on the imaging with coherent radiation, the shape of the target was degraded by the interference pattern of the illuminated sub-THz waves. The contrast of the image when using incoherent radiation was improved without obscuring the shape of the target by increasing the number of photomixers. We also confirmed that there was good visibility for active imaging using incoherent sub-THz illumination even though thick smoke was presented. These results indicate that the use of incoherent sub-THz waves and an array of photomixers should enable a sub-THz illuminator with a high level of brightness to be used for active imaging

  6. Long-range night/day human identification using active-SWIR imaging

    NASA Astrophysics Data System (ADS)

    Lemoff, Brian E.; Martin, Robert B.; Sluch, Mikhail; Kafka, Kristopher M.; McCormick, William; Ice, Robert

    2013-06-01

    Positive identification of personnel from a safe distance is a long-standing need for security and defense applications. Advances in computer face recognition have made this a reliable means of identification when facial imagery of sufficient resolution is available to be matched against a database of mug shots. Long-range identification at night requires that the face be actively illuminated; however, for visible and NIR illumination, the intensity required to produce high-resolution long-range imagery typically creates an eye-safety hazard. SWIR illumination makes active- SWIR imaging a promising approach to long-range night-time identification. We will describe an active-SWIR imaging system that is being developed to covertly detect, track, zoom in on, and positively identify a human target, night or day, at hundreds of meters range. The SWIR illuminator pans, tilts, and zooms with the imager to always just fill the imager field of view. The illuminator meets Class 1 eye-safety limits (safe even with magnifying optics) at the intended target, and meets Class 1M eye-safety limits (safe to the naked eye) at point-blank range. Close-up night-time facial imagery will be presented along with experimental face recognition performance results for matching SWIR imagery to a database of visible mug shots at distance.

  7. 76 FR 18511 - Notice of Decision To Issue Permits for the Importation of Fresh Figs From Chile into the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-04

    ... notice \\1\\ in the Federal Register on February 9, 2010 (75 FR 6344-6345, Docket No. APHIS-2009-0097), in... on May 12, 2010 (75 FR 26707-26708). \\1\\ To view the February 2010 notice and the comments we... figs in the recommended treatment may not kill eggs of the insects of concern because eggs would...

  8. Short cavity active mode locking fiber laser for optical sensing and imaging

    NASA Astrophysics Data System (ADS)

    Lee, Hwi Don; Han, Ga Hee; Jeong, Syung Won; Jeong, Myung Yung; Kim, Chang-Seok; Shin, Jun Geun; Lee, Byeong Ha; Eom, Tae Joong

    2014-05-01

    We demonstrate a highly linear wavenumber- swept active mode locking (AML) fiber laser for optical sensing and imaging without any wavenumber-space resampling process. In this all-electric AML wavenumber-swept mechanism, a conventional wavelength selection filter is eliminated and, instead, the suitable programmed electric modulation signal is directly applied to the gain medium. Various types of wavenumber (or wavelength) tunings can be implemented because of the filter-less cavity configuration. Therefore, we successfully demonstrate a linearly wavenumber-swept AML fiber laser with 26.5 mW of output power to obtain an in-vivo OCT image at the 100 kHz swept rate.

  9. An electrically-activated dynamic tissue-equivalent phantom for assessment of diffuse optical imaging systems.

    PubMed

    Hebden, Jeremy C; Brunker, Joanna; Correia, Teresa; Price, Ben D; Gibson, Adam P; Everdell, N L

    2008-01-21

    A novel design of solid dynamic phantom with tissue-like optical properties is presented, which contains variable regions of contrast which are activated electrically. Reversible changes in absorption are produced by localized heating of targets impregnated with thermochromic pigment. A portable, battery-operated prototype has been constructed, and its optical and temporal characteristics have been investigated. The phantom has been developed as a means of assessing the performance of diffuse optical imaging systems, such as those used to monitor haemodynamic changes in the brain and other tissues. Images of the phantom have been reconstructed using data acquired with a continuous wave optical topography system. PMID:18184989

  10. An electrically-activated dynamic tissue-equivalent phantom for assessment of diffuse optical imaging systems

    NASA Astrophysics Data System (ADS)

    Hebden, Jeremy C.; Brunker, Joanna; Correia, Teresa; Price, Ben D.; Gibson, Adam P.; Everdell, N. L.

    2008-01-01

    A novel design of solid dynamic phantom with tissue-like optical properties is presented, which contains variable regions of contrast which are activated electrically. Reversible changes in absorption are produced by localized heating of targets impregnated with thermochromic pigment. A portable, battery-operated prototype has been constructed, and its optical and temporal characteristics have been investigated. The phantom has been developed as a means of assessing the performance of diffuse optical imaging systems, such as those used to monitor haemodynamic changes in the brain and other tissues. Images of the phantom have been reconstructed using data acquired with a continuous wave optical topography system.

  11. Nanometric resolution magnetic resonance imaging methods for mapping functional activity in neuronal networks

    PubMed Central

    Boretti, Albert; Castelletto, Stefania

    2016-01-01

    This contribution highlights and compares some recent achievements in the use of k-space and real space imaging (scanning probe and wide-filed microscope techniques), when applied to a luminescent color center in diamond, known as nitrogen vacancy (NV) center. These techniques combined with the optically detected magnetic resonance of NV, provide a unique platform to achieve nanometric magnetic resonance imaging (MRI) resolution of nearby nuclear spins (known as nanoMRI), and nanometric NV real space localization. • Atomic size optically detectable spin probe. • High magnetic field sensitivity and nanometric resolution. • Non-invasive mapping of functional activity in neuronal networks. PMID:27144128

  12. Development of CMOS Active Pixel Image Sensors for Low Cost Commercial Applications

    NASA Technical Reports Server (NTRS)

    Gee, R.; Kemeny, S.; Kim, Q.; Mendis, S.; Nakamura, J.; Nixon, R.; Ortiz, M.; Pain, B.; Staller, C.; Zhou, Z; Fossum, E.

    1994-01-01

    JPL, under sponsorship from the NASA Office of Advanced Concepts and Technology, has been developing a second-generation solid-state image sensor technology. Charge-coupled devices (CCD) are a well-established first generation image sensor technology. For both commercial and NASA applications, CCDs have numerous shortcomings. In response, the active pixel sensor (APS) technology has been under research. The major advantages of APS technology are the ability to integrate on-chip timing, control, signal-processing and analog-to-digital converter functions, reduced sensitivity to radiation effects, low power operation, and random access readout.

  13. Nanometric resolution magnetic resonance imaging methods for mapping functional activity in neuronal networks.

    PubMed

    Boretti, Albert; Castelletto, Stefania

    2016-01-01

    This contribution highlights and compares some recent achievements in the use of k-space and real space imaging (scanning probe and wide-filed microscope techniques), when applied to a luminescent color center in diamond, known as nitrogen vacancy (NV) center. These techniques combined with the optically detected magnetic resonance of NV, provide a unique platform to achieve nanometric magnetic resonance imaging (MRI) resolution of nearby nuclear spins (known as nanoMRI), and nanometric NV real space localization. •Atomic size optically detectable spin probe.•High magnetic field sensitivity and nanometric resolution.•Non-invasive mapping of functional activity in neuronal networks. PMID:27144128

  14. Person detection in hyperspectral images via skin segmentation using an active learning approach

    NASA Astrophysics Data System (ADS)

    Marqués, Ion; Graña, Manuel; Sanchez, Stephanie M.; Alkhatib, Mohammed Q.; Velez-Reyes, Miguel

    2015-05-01

    Human skin detection is a computer vision problem that has been widely researched in color images. In this article we deal with this task as an interactive segmentation problem in hyperspectral outdoor images. We have focused on the problem of skin identification in hyperspectral cameras allowing a fine sampling of the light spectrum, so that the information gathered at each pixel is a high dimensional vector. The problem is treated as a classification problem, where we make use of active learning strategies to provide an interactive robust solution reaching high accuracy in a short training/testing cycle.

  15. Exploration of amphoteric and negative refraction imaging of acoustic sources via active metamaterials

    NASA Astrophysics Data System (ADS)

    Wen, Jihong; Shen, Huijie; Yu, Dianlong; Wen, Xisen

    2013-11-01

    The present work describes the design of three flat superlens structures for acoustic source imaging and explores an active acoustic metamaterial (AAM) to realise such a design. The first two lenses are constructed via the coordinate transform method (CTM), and their constituent materials are anisotropic. The third lens consists of a material that has both a negative density and a negative bulk modulus. In these lenses, the quality of the images is “clear” and sharp; thus, the diffraction limit of classical lenses is overcome. Finally, a multi-control strategy is developed to achieve the desired parameters and to eliminate coupling effects in the AAM.

  16. Is being a boy and feeling fat a barrier for physical activity? The association between body image, gender and physical activity among adolescents.

    PubMed

    Kopcakova, Jaroslava; Veselska, Zuzana Dankulincova; Geckova, Andrea Madarasova; van Dijk, Jitse P; Reijneveld, Sijmen A

    2014-11-01

    Regular physical activity leads to physical and mental health benefits. Previous studies have shown physical activity to be associated with body image and gender. The aim of this cross-sectional study was to explore the associations of body image with physical activity of adolescents and whether gender modifies this association. We obtained data on body image and physical activity as part of the Health Behaviour in School-Aged Children study in 2010 from Slovakia (n = 8042, age 11-15 years, 49% boys, response rate: 79.5%). Adolescents answered questions about their body image and the frequency of their physical activity. Sufficient physical activity was more likely in adolescents perceiving themselves as fat (OR = 0.63, 95%CI 0.54-0.73) and in boys (OR = 2.15, 95%CI 1.92-2.42). A poor body image among girls was not associated with physical activity, whereas among boys it was associated with less physical activity. Gender seems to moderate the relationship between body image and physical activity in youths. Health promotion should be targeted in particular at boys with a negative body image, as they are at higher risk of physical inactivity. PMID:25350010

  17. Topographic localization of brain activation in diffuse optical imaging using spherical wavelets

    PubMed Central

    Abdelnour, F; Schmidt, B; Huppert, T J

    2009-01-01

    Diffuse optical imaging is a non-invasive technique that uses near-infrared light to measure changes in brain activity through an array of sensors placed on the surface of the head. Compared to functional MRI, optical imaging has the advantage of being portable while offering the ability to record functional changes in both oxy- and deoxy-hemoglobin within the brain at a high temporal resolution. However, the reconstruction of accurate spatial images of brain activity from optical measurements represents an ill-posed and underdetermined problem that requires regularization. These reconstructions benefit from incorporating prior information about the underlying spatial structure and function of the brain. In this work, we describe a novel image reconstruction approach which uses surface-based wavelets derived from structural MRI to incorporate high-resolution anatomical and structural prior information about the brain. This surface-based approach is used to approximate brain activation patterns through the reconstruction and presentation of topographical (two-dimensional) maps of brain activation directly onto the folded surface of the cortex. The set of wavelet coefficients is directly estimated by a truncated singular-value decomposition based pseudo-inversion of the wavelet projection of the optical forward model. We use a reconstruction metric based on Shannon entropy which quantifies the sparse loading of the wavelet coefficients and is used to determine the optimal truncation and regularization of this inverse model. In this work, examples of the performance of this model are illustrated for several cases of numerical simulation and experimental data with comparison to functional magnetic resonance imaging. PMID:19809125

  18. High-Efficiency Capture of Drug Resistant-Influenza Virus by Live Imaging of Sialidase Activity

    PubMed Central

    Tamoto, Chihiro; Sahara, Keiji; Otsubo, Tadamune; Yokozawa, Tatsuya; Shibahara, Nona; Wada, Hirohisa; Minami, Akira; Ikeda, Kiyoshi; Suzuki, Takashi

    2016-01-01

    Influenza A and B viruses possess a neuraminidase protein that shows sialidase activity. Influenza virus-specific neuraminidase inhibitors (NAIs) are commonly used for clinical treatment of influenza. However, some influenza A and B viruses that are resistant to NAIs have emerged in nature. NAI-resistant viruses have been monitored in public hygiene surveys and the mechanism underlying the resistance has been studied. Here, we describe a new assay for selective detection and isolation of an NAI-resistant virus in a speedy and easy manner by live fluorescence imaging of viral sialidase activity, which we previously developed, in order to achieve high-efficiency capture of an NAI-resistant virus. An NAI-resistant virus maintains sialidase activity even at a concentration of NAI that leads to complete deactivation of the virus. Infected cells and focuses (infected cell populations) of an oseltamivir-resistant virus were selectively visualized by live fluorescence sialidase imaging in the presence of oseltamivir, resulting in high-efficiency isolation of the resistant viruses. The use of a combination of other NAIs (zanamivir, peramivir, and laninamivir) in the imaging showed that the oseltamivir-resistant virus isolated in 2008 was sensitive to zanamivir and laninamivir but resistant to peramivir. Fluorescence imaging in the presence of zanamivir also succeeded in selective live-cell visualization of cells that expressed zanamivir-resistant NA. Fluorescence imaging of NAI-resistant sialidase activity will be a powerful method for study of the NAI resistance mechanism, for public monitoring of NAI-resistant viruses, and for development of a new NAI that shows an effect on various NAI-resistant mutations. PMID:27232333

  19. Topographic localization of brain activation in diffuse optical imaging using spherical wavelets.

    PubMed

    Abdelnour, F; Schmidt, B; Huppert, T J

    2009-10-21

    Diffuse optical imaging is a non-invasive technique that uses near-infrared light to measure changes in brain activity through an array of sensors placed on the surface of the head. Compared to functional MRI, optical imaging has the advantage of being portable while offering the ability to record functional changes in both oxy- and deoxy-hemoglobin within the brain at a high temporal resolution. However, the reconstruction of accurate spatial images of brain activity from optical measurements represents an ill-posed and underdetermined problem that requires regularization. These reconstructions benefit from incorporating prior information about the underlying spatial structure and function of the brain. In this work, we describe a novel image reconstruction approach which uses surface-based wavelets derived from structural MRI to incorporate high-resolution anatomical and structural prior information about the brain. This surface-based approach is used to approximate brain activation patterns through the reconstruction and presentation of topographical (two-dimensional) maps of brain activation directly onto the folded surface of the cortex. The set of wavelet coefficients is directly estimated by a truncated singular-value decomposition based pseudo-inversion of the wavelet projection of the optical forward model. We use a reconstruction metric based on Shannon entropy which quantifies the sparse loading of the wavelet coefficients and is used to determine the optimal truncation and regularization of this inverse model. In this work, examples of the performance of this model are illustrated for several cases of numerical simulation and experimental data with comparison to functional magnetic resonance imaging. PMID:19809125

  20. Parahippocampal activation evoked by masked traumatic images in posttraumatic stress disorder: a functional MRI study.

    PubMed

    Sakamoto, Hideshi; Fukuda, Rin; Okuaki, Tomoyuki; Rogers, Mark; Kasai, Kiyoto; Machida, Toru; Shirouzu, Ichiro; Yamasue, Hidenori; Akiyama, Tsuyoshi; Kato, Nobumasa

    2005-07-01

    Posttraumatic stress disorder (PTSD) has been widely studied, but its neural mechanism is still unclear. The purpose of this study is to identify dysfunctional areas in PTSD throughout the whole brain to help to elucidate the neural mechanisms of PTSD. Sixteen patients with PTSD and sixteen healthy controls participated in this study. Traumatic images under perceptual threshold including scenes of earthquakes, traffic accidents, ambulances, emergency rooms, and crimes were presented to the participants, and brain activation was measured using functional MRI. Functional brain images of both groups were evaluated with random effect analysis for the whole brain. In the control group, activation in the ventral frontoparietal areas correlated significantly with presentation of the masked traumatic stimuli. In the PTSD group, activation was not observed in these areas, but significant activation correlated with the masked traumatic stimuli in the parahippocampal region including the left parahippocampal gyrus and tail of the left hippocampus. These results suggest that in PTSD patients activation in the ventral frontoparietal network associated with visual attention processing is attenuated, while the left hippocampal area associated with episodic and autobiographical memory is abnormally easily activated. This pattern of activation corresponds well to the clinical characteristics of PTSD, in which even slight traumatic stimuli tend to induce intrusive recollection or flashbacks, despite a general decrease in attention and ability to concentrate. PMID:15955491

  1. Nanoparticulate assemblies of amphiphiles and diagnostically active materials for multimodality imaging.

    PubMed

    Mulder, Willem J M; Strijkers, Gustav J; van Tilborg, Geralda A F; Cormode, David P; Fayad, Zahi A; Nicolay, Klaas

    2009-07-21

    , with the main focus on magnetic resonance imaging (MRI), optical techniques, and transmission electron microscopy (TEM). The functionalization of the nanoparticles and the modulation of their pharmacokinetics are discussed. Their application for molecular imaging of key processes in cancer and cardiovascular disease are shown. Finally, we discuss a recent development in which the endogenous nanoparticle HDL was modified to carry different diagnostically active nanocrystal cores to enable multimodal imaging of macrophages in experimental atherosclerosis. The multimodal characteristics of the different contrast agent platforms have proven to be extremely valuable for validation purposes and for understanding mechanisms of particle-target interaction at different levels, ranging from the entire organism down to cellular organelles. PMID:19435319

  2. Local adaptive approach toward segmentation of microscopic images of activated sludge flocs

    NASA Astrophysics Data System (ADS)

    Khan, Muhammad Burhan; Nisar, Humaira; Ng, Choon Aun; Lo, Po Kim; Yap, Vooi Voon

    2015-11-01

    Activated sludge process is a widely used method to treat domestic and industrial effluents. The conditions of activated sludge wastewater treatment plant (AS-WWTP) are related to the morphological properties of flocs (microbial aggregates) and filaments, and are required to be monitored for normal operation of the plant. Image processing and analysis is a potential time-efficient monitoring tool for AS-WWTPs. Local adaptive segmentation algorithms are proposed for bright-field microscopic images of activated sludge flocs. Two basic modules are suggested for Otsu thresholding-based local adaptive algorithms with irregular illumination compensation. The performance of the algorithms has been compared with state-of-the-art local adaptive algorithms of Sauvola, Bradley, Feng, and c-mean. The comparisons are done using a number of region- and nonregion-based metrics at different microscopic magnifications and quantification of flocs. The performance metrics show that the proposed algorithms performed better and, in some cases, were comparable to the state-of the-art algorithms. The performance metrics were also assessed subjectively for their suitability for segmentations of activated sludge images. The region-based metrics such as false negative ratio, sensitivity, and negative predictive value gave inconsistent results as compared to other segmentation assessment metrics.

  3. In vivo imaging of brain metabolism activity using a phosphorescent oxygen-sensitive probe

    PubMed Central

    Tsytsarev, Vassiliy; Arakawa, Hiroyuki; Borisov, Sergei; Pumbo, Elena; Erzurumlu, Reha S.; Papkovsky, Dmitri B.

    2013-01-01

    Several approaches have been adopted for real-time imaging of neural activity in vivo. We tested a new cell-penetrating phosphorescent oxygen-sensitive probe, NanO2-IR, to monitor temporal and spatial dynamics of oxygen metabolism in the neocortex following peripheral sensory stimulation. Probe solution was applied to the surface of anesthetized mouse brain; optical imaging was performed using a MiCAM-02 system. Trains of whisker stimuli were delivered and associated changes in phosphorescent signal were recorded in the contralateral somatosensory (“barrel”) cortex. Sensory stimulation led to changes in oxygenation of activated areas of the barrel cortex. The oxygen imaging results were compared to those produced by the voltage-sensitive dye RH-1691. While the signals emitted by the two probes differed in shape and amplitude, they both faithfully indicated specific whisker evoked cortical activity. Thus, NanO2-IR probe can be used as a tool in visualization and realtime analysis of sensory- evoked neural activity in vivo. PMID:23624034

  4. Redox-initiated hydrogel system for detection and real-time imaging of cellulolytic enzyme activity.

    PubMed

    Malinowska, Klara H; Verdorfer, Tobias; Meinhold, Aylin; Milles, Lukas F; Funk, Victor; Gaub, Hermann E; Nash, Michael A

    2014-10-01

    Understanding the process of biomass degradation by cellulolytic enzymes is of urgent importance for biofuel and chemical production. Optimizing pretreatment conditions and improving enzyme formulations both require assays to quantify saccharification products on solid substrates. Typically, such assays are performed using freely diffusing fluorophores or dyes that measure reducing polysaccharide chain ends. These methods have thus far not allowed spatial localization of hydrolysis activity to specific substrate locations with identifiable morphological features. Here we describe a hydrogel reagent signaling (HyReS) system that amplifies saccharification products and initiates crosslinking of a hydrogel that localizes to locations of cellulose hydrolysis, allowing for imaging of the degradation process in real time. Optical detection of the gel in a rapid parallel format on synthetic and natural pretreated solid substrates was used to quantify activity of T. emersonii and T. reesei enzyme cocktails. When combined with total internal reflection fluorescence microscopy and AFM imaging, the reagent system provided a means to visualize enzyme activity in real-time with high spatial resolution (<2 μm). These results demonstrate the versatility of the HyReS system in detecting cellulolytic enzyme activity and suggest new opportunities in real-time chemical imaging of biomass depolymerization. PMID:25116339

  5. Active illumination using a digital micromirror device for quantitative phase imaging.

    PubMed

    Shin, Seungwoo; Kim, Kyoohyun; Yoon, Jonghee; Park, YongKeun

    2015-11-15

    We present a powerful and cost-effective method for active illumination using a digital micromirror device (DMD) for quantitative phase-imaging techniques. Displaying binary illumination patterns on a DMD with appropriate spatial filtering, plane waves with various illumination angles are generated and impinged onto a sample. Complex optical fields of the sample obtained with various incident angles are then measured via Mach-Zehnder interferometry, from which a high-resolution 2D synthetic aperture phase image and a 3D refractive index tomogram of the sample are reconstructed. We demonstrate the fast and stable illumination-control capability of the proposed method by imaging colloidal spheres and biological cells. The capability of high-speed optical diffraction tomography is also demonstrated by measuring 3D Brownian motion of colloidal particles with the tomogram acquisition rate of 100 Hz. PMID:26565886

  6. A Model for Diagnosing Breast Cancerous Tissue from Thermal Images Using Active Contour and Lyapunov Exponent

    PubMed Central

    GHAYOUMI ZADEH, Hossein; HADDADNIA, Javad; MONTAZERI, Alimohammad

    2016-01-01

    Background: The segmentation of cancerous areas in breast images is important for the early detection of disease. Thermal imaging has advantages, such as being non-invasive, non-radiation, passive, quick, painless, inexpensive, and non-contact. Imaging technique is the focus of this research. Methods: The proposed model in this paper is a combination of surf and corners that are very resistant. Obtained features are resistant to changes in rotation and revolution then with the help of active contours, this feature has been used for segmenting cancerous areas. Results: Comparing the obtained results from the proposed method and mammogram show that proposed method is Accurate and appropriate. Benign and malignance of segmented areas are detected by Lyapunov exponent. Values obtained include TP=91.31%, FN=8.69%, FP=7.26%. Conclusion: The proposed method can classify those abnormally segmented areas of the breast, to the Benign and malignant cancer. PMID:27398339

  7. Functional photoacoustic imaging to observe regional brain activation induced by cocaine hydrochloride

    NASA Astrophysics Data System (ADS)

    Jo, Janggun; Yang, Xinmai

    2011-09-01

    Photoacoustic microscopy (PAM) was used to detect small animal brain activation in response to drug abuse. Cocaine hydrochloride in saline solution was injected into the blood stream of Sprague Dawley rats through tail veins. The rat brain functional change in response to the injection of drug was then monitored by the PAM technique. Images in the coronal view of the rat brain at the locations of 1.2 and 3.4 mm posterior to bregma were obtained. The resulted photoacoustic (PA) images showed the regional changes in the blood volume. Additionally, the regional changes in blood oxygenation were also presented. The results demonstrated that PA imaging is capable of monitoring regional hemodynamic changes induced by drug abuse.

  8. Statistical correlation of low-altitude ENA emissions with geomagnetic activity from IMAGE/MENA observations

    NASA Astrophysics Data System (ADS)

    Mackler, D. A.; Jahn, J.-M.; Perez, J. D.; Pollock, C. J.; Valek, P. W.

    2016-03-01

    Plasma sheet particles transported Earthward during times of active magnetospheric convection can interact with exospheric/thermospheric neutrals through charge exchange. The resulting Energetic Neutral Atoms (ENAs) are free to leave the influence of the magnetosphere and can be remotely detected. ENAs associated with low-altitude (300-800 km) ion precipitation in the high-latitude atmosphere/ionosphere are termed low-altitude emissions (LAEs). Remotely observed LAEs are highly nonisotropic in velocity space such that the pitch angle distribution at the time of charge exchange is near 90°. The Geomagnetic Emission Cone of LAEs can be mapped spatially, showing where proton energy is deposited during times of varying geomagnetic activity. In this study we present a statistical look at the correlation between LAE flux (intensity and location) and geomagnetic activity. The LAE data are from the MENA imager on the IMAGE satellite over the declining phase of solar cycle 23 (2000-2005). The SYM-H, AE, and Kp indices are used to describe geomagnetic activity. The goal of the study is to evaluate properties of LAEs in ENA images and determine if those images can be used to infer properties of ion precipitation. Results indicate a general positive correlation to LAE flux for all three indices, with the SYM-H showing the greatest sensitivity. The magnetic local time distribution of LAEs is centered about midnight and spreads with increasing activity. The invariant latitude for all indices has a slightly negative correlation. The combined results indicate LAE behavior similar to that of ion precipitation.

  9. Flavoprotein Autofluorescence Imaging of Visual System Activity in Zebra Finches and Mice

    PubMed Central

    Michael, Neethu; Bischof, Hans-Joachim; Löwel, Siegrid

    2014-01-01

    Large-scale brain activity patterns can be visualized by optical imaging of intrinsic signals (OIS) based on activity-dependent changes in the blood oxygenation level. Another method, flavoprotein autofluorescence imaging (AFI), exploits the mitochondrial flavoprotein autofluorescence, which is enhanced during neuronal activity. In birds, topographic mapping of visual space has been shown in the visual wulst, the avian homologue of the mammalian visual cortex by using OIS. We here applied the AFI method to visualize topographic maps in the visual wulst because with OIS, which depends on blood flow changes, blood vessel artifacts often obscure brain activity maps. We then compared both techniques quantitatively in zebra finches and in C57Bl/6J mice using the same setup and stimulation conditions. In addition to experiments with craniotomized animals, we also examined mice with intact skull (in zebra finches, intact skull imaging is not feasible probably due to the skull construction). In craniotomized animals, retinotopic maps were obtained by both methods in both species. Using AFI, artifacts caused by blood vessels were generally reduced, the magnitude of neuronal activity significantly higher and the retinotopic map quality better than that obtained by OIS in both zebra finches and mice. In contrast, our measurements in non-craniotomized mice did not reveal any quantitative differences between the two methods. Our results thus suggest that AFI is the method of choice for investigations of visual processing in zebra finches. In mice, however, if researchers decide to use the advantages of imaging through the intact skull, they will not be able to exploit the higher signals obtainable by the AFI-method. PMID:24400130

  10. Real time in vivo imaging and measurement of serine protease activity in the mouse hippocampus using a dedicated complementary metal-oxide semiconductor imaging device.

    PubMed

    Ng, David C; Tamura, Hideki; Tokuda, Takashi; Yamamoto, Akio; Matsuo, Masamichi; Nunoshita, Masahiro; Ishikawa, Yasuyuki; Shiosaka, Sadao; Ohta, Jun

    2006-09-30

    The aim of the present study is to demonstrate the application of complementary metal-oxide semiconductor (CMOS) imaging technology for studying the mouse brain. By using a dedicated CMOS image sensor, we have successfully imaged and measured brain serine protease activity in vivo, in real-time, and for an extended period of time. We have developed a biofluorescence imaging device by packaging the CMOS image sensor which enabled on-chip imaging configuration. In this configuration, no optics are required whereby an excitation filter is applied onto the sensor to replace the filter cube block found in conventional fluorescence microscopes. The fully packaged device measures 350 microm thick x 2.7 mm wide, consists of an array of 176 x 144 pixels, and is small enough for measurement inside a single hemisphere of the mouse brain, while still providing sufficient imaging resolution. In the experiment, intraperitoneally injected kainic acid induced upregulation of serine protease activity in the brain. These events were captured in real time by imaging and measuring the fluorescence from a fluorogenic substrate that detected this activity. The entire device, which weighs less than 1% of the body weight of the mouse, holds promise for studying freely moving animals. PMID:16542733

  11. Neural portraits of perception: reconstructing face images from evoked brain activity.

    PubMed

    Cowen, Alan S; Chun, Marvin M; Kuhl, Brice A

    2014-07-01

    Recent neuroimaging advances have allowed visual experience to be reconstructed from patterns of brain activity. While neural reconstructions have ranged in complexity, they have relied almost exclusively on retinotopic mappings between visual input and activity in early visual cortex. However, subjective perceptual information is tied more closely to higher-level cortical regions that have not yet been used as the primary basis for neural reconstructions. Furthermore, no reconstruction studies to date have reported reconstructions of face images, which activate a highly distributed cortical network. Thus, we investigated (a) whether individual face images could be accurately reconstructed from distributed patterns of neural activity, and (b) whether this could be achieved even when excluding activity within occipital cortex. Our approach involved four steps. (1) Principal component analysis (PCA) was used to identify components that efficiently represented a set of training faces. (2) The identified components were then mapped, using a machine learning algorithm, to fMRI activity collected during viewing of the training faces. (3) Based on activity elicited by a new set of test faces, the algorithm predicted associated component scores. (4) Finally, these scores were transformed into reconstructed images. Using both objective and subjective validation measures, we show that our methods yield strikingly accurate neural reconstructions of faces even when excluding occipital cortex. This methodology not only represents a novel and promising approach for investigating face perception, but also suggests avenues for reconstructing 'offline' visual experiences-including dreams, memories, and imagination-which are chiefly represented in higher-level cortical areas. PMID:24650597

  12. Body image emotions, perceptions, and cognitions distinguish physically active and inactive smokers

    PubMed Central

    Contreras, Gisèle A.; Sabiston, Catherine M.; O'Loughlin, Erin K.; Bélanger, Mathieu; O'Loughlin, Jennifer

    2015-01-01

    Objectives To determine if body image emotions (body-related shame and guilt, weight-related stress), perceptions (self-perceived overweight), or cognitions (trying to change weight) differ between adolescents characterized by smoking and physical activity (PA) behavior. Methods Data for this cross-sectional analysis were collected in 2010–11 and were available for 1017 participants (mean (SD) age = 16.8 (0.5) years). Participants were categorized according to smoking and PA status into four groups: inactive smokers, inactive non-smokers, active smokers and active non-smokers. Associations between body image emotions, perceptions and cognitions, and group membership were estimated in multinomial logistic regression. Results Participants who reported body-related shame were less likely (OR (95% CI) = 0.52 (0.29–0.94)) to be in the active smoker group than the inactive smoker group; those who reported body-related guilt and those trying to gain weight were more likely (2.14 (1.32–3.48) and 2.49 (1.22–5.08), respectively) to be in the active smoker group than the inactive smoker group; those who were stressed about weight and those perceiving themselves as overweight were less likely to be in the active non-smoker group than the inactive smoker group (0.79 (0.64–0.97) and 0.41 (0.19–0.89), respectively). Conclusion Body image emotions and cognitions differentiated the active smoker group from the other three groups. PMID:26844062

  13. Automated detection of lung tumors in PET/CT images using active contour filter

    NASA Astrophysics Data System (ADS)

    Teramoto, Atsushi; Adachi, Hayato; Tsujimoto, Masakazu; Fujita, Hiroshi; Takahashi, Katsuaki; Yamamuro, Osamu; Tamaki, Tsuneo; Nishio, Masami; Kobayashi, Toshiki

    2015-03-01

    In a previous study, we developed a hybrid tumor detection method that used both computed tomography (CT) and positron emission tomography (PET) images. However, similar to existing computer-aided detection (CAD) schemes, it was difficult to detect low-contrast lesions that touch to the normal organs such as the chest wall or blood vessels in the lung. In the current study, we proposed a novel lung tumor detection method that uses active contour filters to detect the nodules deemed "difficult" in previous CAD schemes. The proposed scheme detects lung tumors using both CT and PET images. As for the detection in CT images, the massive region was first enhanced using an active contour filter (ACF), which is a type of contrast enhancement filter that has a deformable kernel shape. The kernel shape involves closed curves that are connected by several nodes that move iteratively in order to enclose the massive region. The final output of ACF is the difference between the maximum pixel value on the deformable kernel, and pixel value on the center of the filter kernel. Subsequently, the PET images were binarized to detect the regions of increased uptake. The results were integrated, followed by the false positive reduction using 21 characteristic features and three support vector machines. In the experiment, we evaluated the proposed method using 100 PET/CT images. More than half of nodules missed using previous methods were accurately detected. The results indicate that our method may be useful for the detection of lung tumors using PET/CT images.

  14. Active infrared hyperspectral imaging system using a broadly tunable optical parametric oscillator

    NASA Astrophysics Data System (ADS)

    Malcolm, G. P. A.; Maker, G. T.; Robertson, G.; Dunn, M. H.; Stothard, D. J. M.

    2009-09-01

    The in situ identification and spatial location of gases, discrete liquid droplets and residues on surfaces is a technically challenging problem. Active Infrared (IR) hyperspectral imaging is a powerful technique that combines real-time imaging and optical spectroscopy for "standoff" detection of suspected chemical substances, including chemical warfare agents, toxic industrial chemicals, explosives and narcotics. An active IR hyperspectral imaging system requires a coherent, broadly tunable IR light source of high spectral purity, in order to detect a broad range of target substances. In this paper we outline a compact and power-efficient IR illumination source with high stability, efficiency, tuning range and spectral purity based upon an optical parametric oscillator (OPO). The fusion of established OPO technology with novel diode-pumped laser technology and electro-mechanical scanning has enabled a broadly applicable imaging system. This system is capable of hyperspectral imaging at both Near-IR (1.3 - 1.9 μm) and Mid-IR (2.3 - 4.6 μm) wavelengths simultaneously with a line width of < 3 cm-1. System size and complexity are minimised by using a dual InGaAs/InSb single element detector, and images are acquired by raster scanning the coaxial signal and idler beams simultaneously, at ranges up to 20 m. Reflection, absorption and scatter of incident radiation by chemical targets and their surroundings provide a method for spatial location, and characteristic spectra obtained from each sample can be used to identify targets uniquely. To date, we have recognized liquids in sample sizes as small 20 μl-and gases with sensitivity as high as 10ppm.m-at detection standoff distances > 10 m.

  15. The use of fluorine-18 fluorodeoxyglucose positron emission tomography for imaging human motor neuronal activation in the brain

    PubMed Central

    PAHK, KISOO; PARK, KUN-WOO; PYUN, SUNG BOM; LEE, JAE SUNG; KIM, SUNGEUN; CHOE, JAE GOL

    2015-01-01

    The present study aimed to visualize human motor neuronal activation in the brain using fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET), and to develop an FDG-PET procedure for imaging neuronal activation. A male volunteer underwent 20 min periods of rest and motor activation, whilst being assessed using FDG-PET on two consecutive days. The motor task, which involved repetitively grasping and releasing the right hand, was performed during the initial 5 min of the activation period. Subtraction of the rest period signal from the activation PET images was performed using the subtraction ictal single-photon emission computed tomography co-registered to magnetic resonance imaging method. The subtracted image detected activation of the contralateral (left) primary motor cortex, supplementary motor area, and ipsilateral (right) cerebellum. In the present study, FDG-PET detected significantly increased motor-associated activation of the brain in a subject performing a motor task. PMID:26668604

  16. A passive-flow microfluidic device for imaging latent HIV activation dynamics in single T cells

    PubMed Central

    Gearhart, Larisa M.; Miller-Jensen, Kathryn

    2015-01-01

    Quantifying cell-to-cell variability in drug response dynamics is important when evaluating therapeutic efficacy. For example, optimizing latency reversing agents (LRAs) for use in a clinical “activate-and-kill” strategy to purge the latent HIV reservoir in patients requires minimizing heterogeneous viral activation dynamics. To evaluate how heterogeneity in latent HIV activation varies across a range of LRAs, we tracked drug-induced response dynamics in single cells via live-cell imaging using a latent HIV–GFP reporter virus in a clonal Jurkat T cell line. To enable these studies in suspension cells, we designed a simple method to capture an array of single Jurkat T cells using a passive-flow microfluidic device. Our device, which does not require external pumps or tubing, can trap hundreds of cells within minutes with a high retention rate over 12 hours of imaging. Using this device, we quantified heterogeneity in viral activation stimulated by transcription factor (TF) activators and histone deacetylase (HDAC) inhibitors. Generally, TF activators resulted in both faster onset of viral activation and faster rates of production, while HDAC inhibitors resulted in more uniform onset times, but more heterogeneous rates of production. Finally, we demonstrated that while onset time of viral gene expression and rate of viral production together predict total HIV activation, rate and onset time were not correlated within the same individual cell, suggesting that these features are regulated independently. Overall, our results reveal drug-specific patterns of noisy HIV activation dynamics not previously identified in static single-cell assays, which may require consideration for the most effective activate-and-kill regime. PMID:26138068

  17. In-vitro and in-vivo imaging of MMP activity in cartilage and joint injury

    PubMed Central

    Fukui, Tomoaki; Tenborg, Elizabeth; Yik, Jasper H. N.; Haudenschild, Dominik R.

    2015-01-01

    Non-destructive detection of cartilage-degrading activities represents an advance in osteoarthritis (OA) research, with implications in studies of OA pathogenesis, progression, and intervention strategies. Matrix metalloproteinases (MMPs) are principal cartilage degrading enzymes that contribute to OA pathogenesis. MMPSense750 is an in-vivo fluorimetric imaging probe with the potential to continuously and non-invasively trace real-time MMP activities, but its use in OA-related research has not been reported. Our objective is to detect and characterize the early degradation activities shortly after cartilage or joint injury with MMPSense750. We determined the appropriate concentration, assay time, and linear range using various concentrations of recombinant MMPs as standards. We then quantified MMP activity from cartilage explants subjected to either mechanical injury or inflammatory cytokine treatment in-vitro. Finally, we performed invivo MMP imaging of a mouse model of post-traumatic OA. Our in-vitro results showed that the optimal assay time was highly dependent on the MMP enzyme. In cartilage explant culture media, mechanical impact or cytokine treatment increased MMP activity. Injured knees of mice showed significantly higher fluorescent signal than uninjured knees. We conclude that MMPSense750 detects human MMP activities and can be used for in-vitro study with cartilage, as well as in-vivo studies of knee injury, and can offering real-time insight into the degradative processes that occurring within the joint before structural changes become evident radiographically. PMID:25817731

  18. Structure and activity of the imbricated wedge of the Gulf of Cadiz from MCS images

    NASA Astrophysics Data System (ADS)

    Calahorrano Betancourt, Alcinoe; Ranero, César R.; Gràcia, Eulàlia

    2015-04-01

    In this work we present new results on the structure and activity of the imbricated wedge of the Gulf of Cadiz based on ˜ 3000 km of multichannel (MCS) profiles acquired off NW Moroccan margin. Seismic images indicates that the imbricated wedge is bounded between the Gulf of Cadiz margin at the north, the Kenitra margin at the south and the Rharb margin at the east. It is imaged as a sedimentary body with variable seismic amplitude, and structured by imbricated thrust sheets similar to an accretionary prism. Its maximum thickness is located at the east region of the gulf. It gradually thins toward the center and south of the gulf, where it is buried by ˜0.3 twts of sedimentary deposits, indicating that the imbricated wedge is actually not growing. It probably stops it s activity at ˜5-6 Ma. The imbricated wedge is overlaid by sedimentary sequences whose oldest unit is uppermost Tortonian. No evidences of gravitational (olistostrom) origin were founded. Active deformation related to plate convergence corresponds mainly to strike-slip faulting and minor thrusting. Mud diapirism is imaged intruding both the imbricated wedge and the overlaying sediments. At the south, the seismic images show normal faulting probably related with an extended continental crust or a continent-ocean transition crust. The age of this extension is probably Triassic-Jurassic, and we propose it as the conjugated margin of the Gulf of Cadiz. Toward the east, MCS profiles image high-amplitude continent-verging reflections corresponding to pervasive normal faulting. These deformation related to a extended terrain, named Rharb margin, seems to act as the backstop of the imbricated wedge, and it is over-thrusted by Prebetic/Flysh sequences off the Strait of Gibraltar.

  19. Phosphorylation at threonine-235 by a ras-dependent mitogen-activated protein kinase cascade is essential for transcription factor NF-IL6.

    PubMed Central

    Nakajima, T; Kinoshita, S; Sasagawa, T; Sasaki, K; Naruto, M; Kishimoto, T; Akira, S

    1993-01-01

    NF-IL6, a member of the basic leucine zipper (bZIP) family transcription factors, is involved in expression of inducible genes involved in immune and inflammatory responses. We observed that coexpression of oncogenic p21ras stimulated the transactivating activity of NF-IL6 and induced phosphorylation of Thr-235 located just N-terminal to the DNA binding domain of NF-IL6. Recently, mitogen-activated protein (MAP) kinases have been shown to be implicated in the cellular response to activated ras. Purified MAP kinases specifically phosphorylated Thr-235 of NF-IL6 in vitro. Mutation of Thr-235 abolished the ras-dependent activation of NF-IL6. From these results, we conclude that NF-IL6 is regulated through phosphorylation by MAP kinases in response to activated ras. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 PMID:8384717

  20. Mesoarchean oceanic sedimentary sequences: Dixon Island-Cleaverville formations of Pilbara vs Komati section of Fig Tree Group in Barberton

    NASA Astrophysics Data System (ADS)

    Kiyokawa, S.; Ito, T.; Ikehara, M.; Yamaguchi, K. E.; Horie, K.; Sakamoto, R.; Takehara, M.; Teraji, S.

    2011-12-01

    During the Neoarchean to Paleoproterozoic, atmospheric conditions varied from lower levels of oxygen contents to oxic conditions in atmosphere, with the Great Oxidation Event occurring at 2.5 Ga (e.g. Canfield, 2005, Farquhar et al., 2007). However, many iron formations and oxic iron rich sediments occur in the Mesoarchean. We evaluate the sedimentation history of some well-preserved Mesoarchean iron rich sequences by focusing on their stratigraphic pattern and geochemical characteristics. Our study focuses on three iron formation bearing deeper facies sedimentary sequences in Mesoarchean - 1) Dixon Island (Pilbara), 2) Cleaverville (Pilbara) and 3) Mapepe (Barberton) formations. The Dixon Island-Cleaverville formations include volcano-sedimentary sequences as indicated by drill core samples (DXCL) (Kiyokawa et al., 2006, Yamaguchi et al., 2009). It shows coarsening and thickening upward black shale-BIF sequences which indicate oceanic caldera environment. Estimated sedimentation rate from Dixon Island Formation (3195+15 Ma) to Cleaverville Formation (3108+13 Ma) is 2-4 cm/1000year. The Komati section of the Mappepe Formation in the Fig Tree Group consists of a more than 300m thick bedded black shale-chert-iron formation sequence. Based on mapping at 1/100 and 1/1000 scales, we reconstructed 150m thick stratigraphic section. This sequence conformably overlies volcanic rocks, which are in turn overlain by iron rich red bed sequences. Organic rich sequences of three different thickness were identified; 1) less than 1mm thick thin laminated black and white chert and pyrite lamination sequence, 2) 3-5 cm thick black shale-chert-iron rich sequence, and 3) 20 cm thick black chert with fine grained volcanic rocks to banded iron formation sequence. Each sequence contains cycles of organic matter rich shale at the bottom, with chert, pyrite or iron rich bed to the top. Total organic carbon of DXCL core reaches maximum values over 3.0 wt%. (ave 1.2 wt%). Total organic carbon

  1. Transferring biomarker into molecular probe: melanin nanoparticle as a naturally active platform for multimodality imaging.

    PubMed

    Fan, Quli; Cheng, Kai; Hu, Xiang; Ma, Xiaowei; Zhang, Ruiping; Yang, Min; Lu, Xiaomei; Xing, Lei; Huang, Wei; Gambhir, Sanjiv Sam; Cheng, Zhen

    2014-10-29

    Developing multifunctional and easily prepared nanoplatforms with integrated different modalities is highly challenging for molecular imaging. Here, we report the successful transfer of an important molecular target, melanin, into a novel multimodality imaging nanoplatform. Melanin is abundantly expressed in melanotic melanomas and thus has been actively studied as a target for melanoma imaging. In our work, the multifunctional biopolymer nanoplatform based on ultrasmall (<10 nm) water-soluble melanin nanoparticle (MNP) was developed and showed unique photoacoustic property and natural binding ability with metal ions (for example, (64)Cu(2+), Fe(3+)). Therefore, MNP can serve not only as a photoacoustic contrast agent, but also as a nanoplatform for positron emission tomography (PET) and magnetic resonance imaging (MRI). Traditional passive nanoplatforms require complicated and time-consuming processes for prebuilding reporting moieties or chemical modifications using active groups to integrate different contrast properties into one entity. In comparison, utilizing functional biomarker melanin can greatly simplify the building process. We further conjugated αvβ3 integrins, cyclic c(RGDfC) peptide, to MNPs to allow for U87MG tumor accumulation due to its targeting property combined with the enhanced permeability and retention (EPR) effect. The multimodal properties of MNPs demonstrate the high potential of endogenous materials with multifunctions as nanoplatforms for molecular theranostics and clinical translation. PMID:25292385

  2. A D-band Active Imager in a SiGe HBT Technology

    NASA Astrophysics Data System (ADS)

    Yoon, Daekeun; Song, Kiryong; Kim, Jungsoo; Kaynak, Mehmet; Tillack, Bernd; Rieh, Jae-Sung

    2015-04-01

    In this paper, an amplifier and a detector operating near 140 GHz have been developed and integrated together with an on-chip antenna for an integrated active imager based on a 0.13-μm SiGe HBT technology. The 5-stage differential common-emitter (CE) amplifier shows a peak gain of 14 dB and noise figure (NF) down to 10 dB around 140 GHz with a DC power dissipation of 18 mW. The common-base (CB) differential detector exhibits a peak responsivity of 52.5 kV/W and a noise equivalent power (NEP) of 3.3 pW/Hz1/2. For the integrated imager, a peak responsivity of 1,740 kV/W and a minimum NEP of 80 fW/Hz1/2 were achieved with a DC power dissipation of 18 mW. With the fabricated active imager with on-chip antenna, which occupies an area of 2,200 × 600 μm2 including the antenna and bonding pads, images of various objects were successfully acquired.

  3. Transferring Biomarker into Molecular Probe: Melanin Nanoparticle as a Naturally Active Platform for Multimodality Imaging

    PubMed Central

    2015-01-01

    Developing multifunctional and easily prepared nanoplatforms with integrated different modalities is highly challenging for molecular imaging. Here, we report the successful transfer of an important molecular target, melanin, into a novel multimodality imaging nanoplatform. Melanin is abundantly expressed in melanotic melanomas and thus has been actively studied as a target for melanoma imaging. In our work, the multifunctional biopolymer nanoplatform based on ultrasmall (<10 nm) water-soluble melanin nanoparticle (MNP) was developed and showed unique photoacoustic property and natural binding ability with metal ions (for example, 64Cu2+, Fe3+). Therefore, MNP can serve not only as a photoacoustic contrast agent, but also as a nanoplatform for positron emission tomography (PET) and magnetic resonance imaging (MRI). Traditional passive nanoplatforms require complicated and time-consuming processes for prebuilding reporting moieties or chemical modifications using active groups to integrate different contrast properties into one entity. In comparison, utilizing functional biomarker melanin can greatly simplify the building process. We further conjugated αvβ3 integrins, cyclic c(RGDfC) peptide, to MNPs to allow for U87MG tumor accumulation due to its targeting property combined with the enhanced permeability and retention (EPR) effect. The multimodal properties of MNPs demonstrate the high potential of endogenous materials with multifunctions as nanoplatforms for molecular theranostics and clinical translation. PMID:25292385

  4. Limits of Active Laser Triangulation as an Instrument for High Precision Plant Imaging

    PubMed Central

    Paulus, Stefan; Eichert, Thomas; Goldbach, Heiner E.; Kuhlmann, Heiner

    2014-01-01

    Laser scanning is a non-invasive method for collecting and parameterizing 3D data of well reflecting objects. These systems have been used for 3D imaging of plant growth and structure analysis. A prerequisite is that the recorded signals originate from the true plant surface. In this paper we studied the effects of species, leaf chlorophyll content and sensor settings on the suitability and accuracy of a commercial 660 nm active laser triangulation scanning device. We found that surface images of Ficus benjamina leaves were inaccurate at low chlorophyll concentrations and a long sensor exposure time. Imaging of the rough waxy leaf surface of leek (Allium porrum) was possible using very low exposure times, whereas at higher exposure times penetration and multiple refraction prevented the correct imaging of the surface. A comparison of scans with varying exposure time enabled the target-oriented analysis to identify chlorotic, necrotic and healthy leaf areas or mildew infestations. We found plant properties and sensor settings to have a strong influence on the accuracy of measurements. These interactions have to be further elucidated before laser imaging of plants is possible with the high accuracy required for e.g., the observation of plant growth or reactions to water stress. PMID:24504106

  5. Unsupervised Feature Learning Improves Prediction of Human Brain Activity in Response to Natural Images

    PubMed Central

    Güçlü, Umut; van Gerven, Marcel A. J.

    2014-01-01

    Encoding and decoding in functional magnetic resonance imaging has recently emerged as an area of research to noninvasively characterize the relationship between stimulus features and human brain activity. To overcome the challenge of formalizing what stimulus features should modulate single voxel responses, we introduce a general approach for making directly testable predictions of single voxel responses to statistically adapted representations of ecologically valid stimuli. These representations are learned from unlabeled data without supervision. Our approach is validated using a parsimonious computational model of (i) how early visual cortical representations are adapted to statistical regularities in natural images and (ii) how populations of these representations are pooled by single voxels. This computational model is used to predict single voxel responses to natural images and identify natural images from stimulus-evoked multiple voxel responses. We show that statistically adapted low-level sparse and invariant representations of natural images better span the space of early visual cortical representations and can be more effectively exploited in stimulus identification than hand-designed Gabor wavelets. Our results demonstrate the potential of our approach to better probe unknown cortical representations. PMID:25101625

  6. Active wideband 350GHz imaging system for concealed-weapon detection

    NASA Astrophysics Data System (ADS)

    Sheen, David M.; Hall, Thomas E.; Severtsen, Ronald H.; McMakin, Douglas L.; Hatchell, Brian K.; Valdez, Patrick L. J.

    2009-05-01

    A prototype active wideband 350 GHz imaging system has been developed to address the urgent need for standoff concealed-weapon detection. This system is based on a wideband, heterodyne, frequency-multiplier-based transceiver system coupled to a quasi-optical focusing system and high-speed conical scanner. This system is able to quickly scan personnel for concealed weapons. Additionally, due to the wideband operation, this system provides accurate ranging information, and the images obtained are fully three-dimensional. Waves in the microwave, millimeter-wave, and terahertz (3 GHz to 1 THz) frequency bands are able to penetrate many optical obscurants, and can be used to form the basis of high-resolution imaging systems. Waves in the sub-millimeter-wave band (300 GHz to 1 THz) are particularly interesting for standoff concealed-weapon detection at ranges of 5 - 20+ meters, due to their unique combination of high resolution and clothing penetration. The Pacific Northwest National Laboratory (PNNL) has previously developed portal screening systems that operate at the lower end of the millimeter-wave frequency range around 30 GHz. These systems are well suited for screening within portals; however, increasing the range of these systems would dramatically reduce the resolution due to diffraction at their relatively long wavelength. In this paper, the standoff 350 GHz imaging system is described in detail and numerous imaging results are presented.

  7. Photoacoustic imaging to detect rat brain activation after cocaine hydrochloride injection

    NASA Astrophysics Data System (ADS)

    Jo, Janggun; Yang, Xinmai

    2011-03-01

    Photoacoustic imaging (PAI) was employed to detect small animal brain activation after the administration of cocaine hydrochloride. Sprague Dawley rats were injected with different concentrations (2.5, 3.0, and 5.0 mg per kg body) of cocaine hydrochloride in saline solution through tail veins. The brain functional response to the injection was monitored by photoacoustic tomography (PAT) system with horizontal scanning of cerebral cortex of rat brain. Photoacoustic microscopy (PAM) was also used for coronal view images. The modified PAT system used multiple ultrasonic detectors to reduce the scanning time and maintain a good signal-to-noise ratio (SNR). The measured photoacoustic signal changes confirmed that cocaine hydrochloride injection excited high blood volume in brain. This result shows PAI can be used to monitor drug abuse-induced brain activation.

  8. Localization of human cortical areas activated on perception of ordered and chaotic images.

    PubMed

    Fokin, V A; Shelepin, Yu E; Kharauzov, A K; Trufanov, G E; Sevost'yanov, A V; Pronin, S V; Koskin, S A

    2008-09-01

    The aims of this study were to identify the locations of areas in the human cortex responsible for describing fragmented test images of different degrees of ordering and to identify the areas taking decisions regarding stimuli of this type. The locations of higher visual functions were determined by functional magnetic resonance imaging (fMRI) using a scanner fitted with a superconducting magnet and a field strength of 1.5 T. The blood oxygen level-dependent (BOLD) method was based on measurements of the level of hemoglobin oxygenation in the blood supplied to the brain. This level was taken to be proportional to the extent of neuron activation in the corresponding part of the gray matter. Stimuli were matrixes consisting of Gabor elements of different orientations. The measure of matrix ordering was the ratio of the number of Gabor elements with identical orientations to the total number of elements in the image. Brain neurons were activated by simultaneous changes in the orientations of all the elements, leading to substitution of one matrix by another. Substitution of the orientation was perceived by observers as rotation of the elements in the matrix. Stimulation by matrixes with a high level of ordering was found to activate the occipital areas of the cortex, V1 and V2 (BA17-BA18), while presentation of matrixes with random element orientations also activated the parietal-temporal cortex, V3, V4, V5 (BA19), and the parietal area (BA7). Brain zones responsible for taking decisions regarding the level of order or chaos in the organization of the stimuli are located in different but close areas of the prefrontal and frontal cortex of the brain, including BA6, BA9, and BA10. The results are assessed in terms of concepts of the roles and interactions of different areas of the human brain during recognition of fragmented images of different degrees of complexity. PMID:18720013

  9. In-vitro and in-vivo imaging of MMP activity in cartilage and joint injury

    SciTech Connect

    Fukui, Tomoaki; Tenborg, Elizabeth; Yik, Jasper H.N.; Haudenschild, Dominik R.

    2015-05-08

    Non-destructive detection of cartilage-degrading activities represents an advance in osteoarthritis (OA) research, with implications in studies of OA pathogenesis, progression, and intervention strategies. Matrix metalloproteinases (MMPs) are principal cartilage degrading enzymes that contribute to OA pathogenesis. MMPSense750 is an in-vivo fluorimetric imaging probe with the potential to continuously and non-invasively trace real-time MMP activities, but its use in OA-related research has not been reported. Our objective is to detect and characterize the early degradation activities shortly after cartilage or joint injury with MMPSense750. We determined the appropriate concentration, assay time, and linear range using various concentrations of recombinant MMPs as standards. We then quantified MMP activity from cartilage explants subjected to either mechanical injury or inflammatory cytokine treatment in-vitro. Finally, we performed in-vivo MMP imaging of a mouse model of post-traumatic OA. Our in-vitro results showed that the optimal assay time was highly dependent on the MMP enzyme. In cartilage explant culture media, mechanical impact or cytokine treatment increased MMP activity. Injured knees of mice showed significantly higher fluorescent signal than uninjured knees. We conclude that MMPSense750 detects human MMP activities and can be used for in-vitro study with cartilage, as well as in-vivo studies of knee injury, and can offering real-time insight into the degradative processes that occurring within the joint before structural changes become evident radiographically. - Highlights: • MMPSense750 is near-infrared fluorescent probe which can detect MMP activity. • MMPSense750 can detect human MMP-3, -9, and -13. • The reaction kinetics with MMPSense750 were different for the three MMPs. • MMPSense750 can visualized real time MMP activity in mouse injured knees. • MMPSense750 is convenient tool to evaluate real-time MMP activity non-invasively.

  10. Characterisation and imaging of cortical impedance changes during interictal and ictal activity in the anaesthetised rat.

    PubMed

    Vongerichten, Anna N; dos Santos, Gustavo Sato; Aristovich, Kirill; Avery, James; McEvoy, Andrew; Walker, Matthew; Holder, David S

    2016-01-01

    Epilepsy affects approximately 50 million people worldwide, and 20-30% of these cases are refractory to antiepileptic drugs. Many patients with intractable epilepsy can benefit from surgical resection of the tissue generating the seizures; however, difficulty in precisely localising seizure foci has limited the number of patients undergoing surgery as well as potentially lowered its effectiveness. Here we demonstrate a novel imaging method for monitoring rapid changes in cerebral tissue impedance occurring during interictal and ictal activity, and show that it can reveal the propagation of pathological activity in the cortex. Cortical impedance was recorded simultaneously to ECoG using a 30-contact electrode mat placed on the exposed cortex of anaesthetised rats, in which interictal spikes (IISs) and seizures were induced by cortical injection of 4-aminopyridine (4-AP), picrotoxin or penicillin. We characterised the tissue impedance responses during IISs and seizures, and imaged these responses in the cortex using Electrical Impedance Tomography (EIT). We found a fast, transient drop in impedance occurring as early as 12ms prior to the IISs, followed by a steep rise in impedance within ~120ms of the IIS. EIT images of these impedance changes showed that they were co-localised and centred at a depth of 1mm in the cortex, and that they closely followed the activity propagation observed in the surface ECoG signals. The fast, pre-IIS impedance drop most likely reflects synchronised depolarisation in a localised network of neurons, and the post-IIS impedance increase reflects the subsequent shrinkage of extracellular space caused by the intense activity. EIT could also be used to picture a steady rise in tissue impedance during seizure activity, which has been previously described. Thus, our results demonstrate that EIT can detect and localise different physiological changes during interictal and ictal activity and, in conjunction with ECoG, may in future improve the

  11. The Cooling Rate of an Active Aa Lava Flow Determined Using an Orbital Imaging Spectrometer

    NASA Astrophysics Data System (ADS)

    Wright, Robert; Garbeil, Harold

    2010-05-01

    The surface temperature of an active lava flow is an important physical property to measure. Through its influence on lava crystallinity, cooling exerts a fundamental control on lava rheology. Remotely sensed thermal radiance data acquired by multispectral sensors such as Landsat Thematic Mapper and the Terra Advanced Spaceborne Thermal Emission and Reflection Radiometer, are of insufficient spectral and radiometric fidelity to allow for realistic determination of lava surface temperatures from Earth orbit. This paper presents results obtained from the analysis of active lava flows using hyperspectral data acquired by NASA's Earth Observing-1 Hyperion imaging spectrometer. The contiguous nature of the measured radiance spectrum in the 0.4-2.5 micron region means that, although sensor saturation most certainly occurs, unsaturated radiance data are always available from even the hottest, and most radiant, active lava flow surfaces. The increased number of wavebands available allows for the assumption of more complex flow surface temperature distributions in the radiance-to-temperature inversion processes. The technique is illustrated by using a hyperspectral image of the active lava lake at Erta Ale volcano, Ethiopia, a well characterized calibration target. We then go on to demonstrate how this approach can be used to constrain the surface cooling rate of an active lava flow at Mount Etna, Sicily, using three images acquired during a four day period in September 2004. The cooling rate of the active channel as determined from space falls within the limits commonly assumed in numerical lava flow models. The results provide insights into the temperature-radiance mixture modeling problem that will aid in the analysis of data acquired by future hyperspectral remote sensing missions, such as NASA's proposed HyspIRI mission.

  12. Characterisation and imaging of cortical impedance changes during interictal and ictal activity in the anaesthetised rat

    PubMed Central

    Vongerichten, Anna N.; Santos, Gustavo Sato dos; Aristovich, Kirill; Avery, James; McEvoy, Andrew; Walker, Matthew; Holder, David S.

    2016-01-01

    Epilepsy affects approximately 50 million people worldwide, and 20–30% of these cases are refractory to antiepileptic drugs. Many patients with intractable epilepsy can benefit from surgical resection of the tissue generating the seizures; however, difficulty in precisely localising seizure foci has limited the number of patients undergoing surgery as well as potentially lowered its effectiveness. Here we demonstrate a novel imaging method for monitoring rapid changes in cerebral tissue impedance occurring during interictal and ictal activity, and show that it can reveal the propagation of pathological activity in the cortex. Cortical impedance was recorded simultaneously to ECoG using a 30-contact electrode mat placed on the exposed cortex of anaesthetised rats, in which interictal spikes (IISs) and seizures were induced by cortical injection of 4-aminopyridine (4-AP), picrotoxin or penicillin. We characterised the tissue impedance responses during IISs and seizures, and imaged these responses in the cortex using Electrical Impedance Tomography (EIT). We found a fast, transient drop in impedance occurring as early as 12 ms prior to the IISs, followed by a steep rise in impedance within ~ 120 ms of the IIS. EIT images of these impedance changes showed that they were co-localised and centred at a depth of 1 mm in the cortex, and that they closely followed the activity propagation observed in the surface ECoG signals. The fast, pre-IIS impedance drop most likely reflects synchronised depolarisation in a localised network of neurons, and the post-IIS impedance increase reflects the subsequent shrinkage of extracellular space caused by the intense activity. EIT could also be used to picture a steady rise in tissue impedance during seizure activity, which has been previously described. Thus, our results demonstrate that EIT can detect and localise different physiological changes during interictal and ictal activity and, in conjunction with ECoG, may in future

  13. Role of irradiation in the green synthesis of silver nanoparticles mediated by fig (Ficus carica) leaf extract

    NASA Astrophysics Data System (ADS)

    Ulug, Bulent; Haluk Turkdemir, M.; Cicek, Ahmet; Mete, Ahmet

    2015-01-01

    Biosynthesis of silver nanoparticles in an aqueous mixture of fig (Ficus carica) leaf extract and AgNO3 solution exposed to a set of irradiances at different wavelengths are studied. Nanoparticle formation for irradiances between 6.5 mW/cm2 and 13.3 mW/cm2 in the 330-550 nm wavelength range is investigated and the results are compared to those of the nanoparticles synthesized in the dark and under direct sunlight. Ultraviolet-visible spectroscopy, Fourier-transform infrared spectroscopy and proton nuclear magnetic resonance spectroscopy, along with particle size analysis and transmission electron microscopy are employed for the characterization of samples and extracts. Irradiance is found to have profound influence on the reduction rates. However, size and spherical shape of the nanoparticles are persistent, irrespective of irradiance and wavelength. Irradiance is discussed to influence the particle formation and aggregation rates through the formation of free radicals in the fig extract.

  14. Role of irradiation in the green synthesis of silver nanoparticles mediated by fig (Ficus carica) leaf extract.

    PubMed

    Ulug, Bulent; Haluk Turkdemir, M; Cicek, Ahmet; Mete, Ahmet

    2015-01-25

    Biosynthesis of silver nanoparticles in an aqueous mixture of fig (Ficus carica) leaf extract and AgNO3 solution exposed to a set of irradiances at different wavelengths are studied. Nanoparticle formation for irradiances between 6.5 mW/cm(2) and 13.3 mW/cm(2) in the 330-550 nm wavelength range is investigated and the results are compared to those of the nanoparticles synthesized in the dark and under direct sunlight. Ultraviolet-visible spectroscopy, Fourier-transform infrared spectroscopy and proton nuclear magnetic resonance spectroscopy, along with particle size analysis and transmission electron microscopy are employed for the characterization of samples and extracts. Irradiance is found to have profound influence on the reduction rates. However, size and spherical shape of the nanoparticles are persistent, irrespective of irradiance and wavelength. Irradiance is discussed to influence the particle formation and aggregation rates through the formation of free radicals in the fig extract. PMID:25062061

  15. Multimodal imaging reveals temporal and spatial microglia and matrix metalloproteinase activity after experimental stroke

    PubMed Central

    Zinnhardt, Bastian; Viel, Thomas; Wachsmuth, Lydia; Vrachimis, Alexis; Wagner, Stefan; Breyholz, Hans-Jörg; Faust, Andreas; Hermann, Sven; Kopka, Klaus; Faber, Cornelius; Dollé, Frédéric; Pappata, Sabina; Planas, Anna M; Tavitian, Bertrand; Schäfers, Michael; Sorokin, Lydia M; Kuhlmann, Michael T; Jacobs, Andreas H

    2015-01-01

    Stroke is the most common cause of death and disability from neurologic disease in humans. Activation of microglia and matrix metalloproteinases (MMPs) is involved in positively and negatively affecting stroke outcome. Novel, noninvasive, multimodal imaging methods visualizing microglial and MMP alterations were employed. The spatio-temporal dynamics of these parameters were studied in relation to blood flow changes. Micro positron emission tomography (μPET) using [18F]BR-351 showed MMP activity within the first days after transient middle cerebral artery occlusion (tMCAo), followed by increased [18F]DPA-714 uptake as a marker for microglia activation with a maximum at 14 days after tMCAo. The inflammatory response was spatially located in the infarct core and in adjacent (penumbral) tissue. For the first time, multimodal imaging based on PET, single photon emission computed tomography, and magnetic resonance imaging revealed insight into the spatio-temporal distribution of critical parameters of poststroke inflammation. This allows further evaluation of novel treatment paradigms targeting the postischemic inflammation. PMID:26126867

  16. Multimodal imaging reveals temporal and spatial microglia and matrix metalloproteinase activity after experimental stroke.

    PubMed

    Zinnhardt, Bastian; Viel, Thomas; Wachsmuth, Lydia; Vrachimis, Alexis; Wagner, Stefan; Breyholz, Hans-Jörg; Faust, Andreas; Hermann, Sven; Kopka, Klaus; Faber, Cornelius; Dollé, Frédéric; Pappata, Sabina; Planas, Anna M; Tavitian, Bertrand; Schäfers, Michael; Sorokin, Lydia M; Kuhlmann, Michael T; Jacobs, Andreas H

    2015-11-01

    Stroke is the most common cause of death and disability from neurologic disease in humans. Activation of microglia and matrix metalloproteinases (MMPs) is involved in positively and negatively affecting stroke outcome. Novel, noninvasive, multimodal imaging methods visualizing microglial and MMP alterations were employed. The spatio-temporal dynamics of these parameters were studied in relation to blood flow changes. Micro positron emission tomography (μPET) using [(18)F]BR-351 showed MMP activity within the first days after transient middle cerebral artery occlusion (tMCAo), followed by increased [(18)F]DPA-714 uptake as a marker for microglia activation with a maximum at 14 days after tMCAo. The inflammatory response was spatially located in the infarct core and in adjacent (penumbral) tissue. For the first time, multimodal imaging based on PET, single photon emission computed tomography, and magnetic resonance imaging revealed insight into the spatio-temporal distribution of critical parameters of poststroke inflammation. This allows further evaluation of novel treatment paradigms targeting the postischemic inflammation. PMID:26126867

  17. Manganese-enhanced MR imaging of brain activation evoked by noxious peripheral electrical stimulation.

    PubMed

    Cha, Myeounghoon; Lee, Kyuhong; Lee, Chulhyun; Cho, Jee-Hyun; Cheong, Chaejoon; Sohn, Jin-Hun; Lee, Bae Hwan

    2016-02-01

    As imaging technology develops, magnetic resonance imaging (MRI) has furthered our understanding of brain function by clarifying the anatomical structure and generating functional imaging data related to information processing in pain conditions. Recent studies have reported that manganese (Mn(2+))-enhanced MRI (MEMRI) provides valuable information about the functions of the central nervous system. The aim of this study was to identify specific brain regions activated during noxious electric stimulation using high-resolution MEMRI. Male Sprague Dawley rats were divided into three groups: naïve, sham electrical stimulation, and noxious electric stimulation. Under urethane with α-chloralose mixture anesthesia, a catheter was placed in the external carotid artery to administrate 20% mannitol and manganese chloride (25mM MnCl2). Noxious electric stimulation (2Hz, 10V) was applied to the hind paw with a needle electrode. Stimulation-induced neuronal activation was detected using 4.7-T MRI. In response to noxious electrical stimulation, remarkable Mn(2+)-enhanced signals were observed in the agranular insular cortex, auditory cortex, primary somatosensory cortex of the hind limb, and granular and dysgranular insular cortex, which correspond to sensory tactile electric stimulus to the hindpaws. These results indicate that the combination of MEMRI with activity-induced Mn(2+)-dependent contrast can delineate functional areas in the rat brain. PMID:26733299

  18. The effect of music video clips on adolescent boys' body image, mood, and schema activation.

    PubMed

    Mulgrew, Kate E; Volcevski-Kostas, Diana; Rendell, Peter G

    2014-01-01

    There is limited research that has examined experimentally the effects of muscular images on adolescent boys' body image, with no research specifically examining the effects of music television. The aim of the current study was to examine the effects of viewing muscular and attractive singers in music video clips on early, mid, and late adolescent boys' body image, mood, and schema activation. Participants were 180 boys in grade 7 (mean age = 12.73 years), grade 9 (mean age = 14.40 years) or grade 11 (mean age = 16.15 years) who completed pre- and post-test measures of mood and body satisfaction after viewing music videos containing male singers of muscular or average appearance. They also completed measures of schema activation and social comparison after viewing the clips. The results showed that the boys who viewed the muscular clips reported poorer upper body satisfaction, lower appearance satisfaction, lower happiness, and more depressive feelings compared to boys who viewed the clips depicting singers of average appearance. There was no evidence of increased appearance schema activation but the boys who viewed the muscular clips did report higher levels of social comparison to the singers. The results suggest that music video clips are a powerful form of media in conveying information about the male ideal body shape and that negative effects are found in boys as young as 12 years. PMID:23443315

  19. Multilabel image classification via high-order label correlation driven active learning.

    PubMed

    Zhang, Bang; Wang, Yang; Chen, Fang

    2014-03-01

    Supervised machine learning techniques have been applied to multilabel image classification problems with tremendous success. Despite disparate learning mechanisms, their performances heavily rely on the quality of training images. However, the acquisition of training images requires significant efforts from human annotators. This hinders the applications of supervised learning techniques to large scale problems. In this paper, we propose a high-order label correlation driven active learning (HoAL) approach that allows the iterative learning algorithm itself to select the informative example-label pairs from which it learns so as to learn an accurate classifier with less annotation efforts. Four crucial issues are considered by the proposed HoAL: 1) unlike binary cases, the selection granularity for multilabel active learning need to be fined from example to example-label pair; 2) different labels are seldom independent, and label correlations provide critical information for efficient learning; 3) in addition to pair-wise label correlations, high-order label correlations are also informative for multilabel active learning; and 4) since the number of label combinations increases exponentially with respect to the number of labels, an efficient mining method is required to discover informative label correlations. The proposed approach is tested on public data sets, and the empirical results demonstrate its effectiveness. PMID:24723538

  20. Cathepsin Activity-Based Probes and Inhibitor for Preclinical Atherosclerosis Imaging and Macrophage Depletion

    PubMed Central

    Abd-Elrahman, Ihab; Kosuge, Hisanori; Wises Sadan, Tommy; Ben-Nun, Yael; Meir, Karen; Rubinstein, Chen; Bogyo, Matthew; McConnell, Michael V.

    2016-01-01

    Background and Purpose Cardiovascular disease is the leading cause of death worldwide, mainly due to an increasing prevalence of atherosclerosis characterized by inflammatory plaques. Plaques with high levels of macrophage infiltration are considered “vulnerable” while those that do not have significant inflammation are considered stable; cathepsin protease activity is highly elevated in macrophages of vulnerable plaques and contributes to plaque instability. Establishing novel tools for non-invasive molecular imaging of macrophages in plaques could aid in preclinical studies and evaluation of therapeutics. Furthermore, compounds that reduce the macrophage content within plaques should ultimately impact care for this disease. Methods We have applied quenched fluorescent cathepsin activity-based probes (ABPs) to a murine atherosclerosis model and evaluated their use for in vivo imaging using fluorescent molecular tomography (FMT), as well as ex vivo fluorescence imaging and fluorescent microscopy. Additionally, freshly dissected human carotid plaques were treated with our potent cathepsin inhibitor and macrophage apoptosis was evaluated by fluorescent microscopy. Results We demonstrate that our ABPs accurately detect murine atherosclerotic plaques non-invasively, identifying cathepsin activity within plaque macrophages. In addition, our cathepsin inhibitor selectively induced cell apoptosis of 55%±10% of the macrophage within excised human atherosclerotic plaques. Conclusions Cathepsin ABPs present a rapid diagnostic tool for macrophage detection in atherosclerotic plaque. Our inhibitor confirms cathepsin-targeting as a promising approach to treat atherosclerotic plaque inflammation. PMID:27532109

  1. Performance improvement and characterization activities for an imaging Fabry-Perot interferometer

    NASA Astrophysics Data System (ADS)

    Larar, Allen M.; Cook, William B.; Flood, Michael A.; Campbell, Joel F.; Boyer, Charles M.

    2008-10-01

    Risk mitigation activities for a prototype imaging Fabry-Perot Interferometer (FPI) system, development originating within NASA's Instrument Incubator Program (IIP) for enabling future space-based atmospheric composition missions, are continuing at NASA Langley Research Center. The system concept and technology are focused on observing tropospheric ozone around 9.6 micron, but also have applicability toward measurement of other trace species in different spectral regions and other applications. The latest results from performance improvement and laboratory characterization activities will be reported, with an emphasis placed on testing performed to evaluate system-level radiometric, spatial, and spectral measurement fidelity.

  2. In situ activation of a doxorubicin prodrug using imaging-capable nanoparticles.

    PubMed

    Khan, Irfan; Agris, Paul F; Yigit, Mehmet V; Royzen, Maksim

    2016-05-01

    A general strategy for image-guided prodrug activation using fluorescently-labeled magnetic iron oxide nanoparticles is described. It is based on a recently developed concept in bio-orthogonal inverse-electron demand Diels-Alder chemistry, which is termed 'click-to-release'. To illustrate a potential new biomedical application of the chemistry, the nanoparticles were modified with tetrazine, as well as near infrared fluorescent (NIRF) cy5.5 dye, while doxorubicin was converted into a prodrug. The nanoparticles taken up by the MDA-MB-231 breast cancer cells efficiently converted the prodrug of doxorubicin into the biologically active chemotherapeutic doxorubicin form. PMID:27076271

  3. Two newly introduced tropical bark and ambrosia beetles (Coleoptera: Curculionidae, Scolytinae) damaging figs (Ficus carica) in southern Italy.

    PubMed

    Faccoli, Massimo; Campo, Giuseppe; Perrotta, Giancarlo; Rassati, Davide

    2016-01-01

    In summer 2014, the bark beetle Hypocryphalus scabricollis (Eichhoff) and the ambrosia beetle Xyleborus bispinatus Eichhoff, species new to Italy and Europe, respectively, were found for the first time in south-eastern Sicily (Italy). Large infestations of the two species were recorded in many plantations of common fig (Ficus carica L.) both in 2014 and 2015. Data concerning insect characteristics, taxonomy, and distribution are briefly reported. PMID:27470760

  4. One step ahead: a parasitoid disperses farther and forms a wider geographic population than its fig wasp host.

    PubMed

    Sutton, Timothy L; Riegler, Markus; Cook, James M

    2016-02-01

    The structure of populations across landscapes influences the dynamics of their interactions with other species. Understanding the geographic structure of populations can thus shed light on the potential for interacting species to co-evolve. Host-parasitoid interactions are widespread in nature and also represent a significant force in the evolution of plant-insect interactions. However, there have been few comparisons of population structure between an insect host and its parasitoid. We used microsatellite markers to analyse the population genetic structure of Pleistodontes imperialis sp. 1, a fig-pollinating wasp of Port Jackson fig (Ficus rubiginosa), and its main parasitoid, Sycoscapter sp. A, in eastern Australia. Besides exploring this host-parasitoid system, our study also constitutes, to our knowledge, the first study of population structure in a nonpollinating fig wasp species. We collected matched samples of pollinators and parasitoids at several sites in two regions separated by up to 2000 km. We found that pollinators occupying the two regions represent distinct populations, but, in contrast, parasitoids formed a single population across the wide geographic range sampled. We observed genetic isolation by distance for each species, but found consistently lower FST and RST values between sites for parasitoids compared with pollinators. Previous studies have indicated that pollinators of monoecious figs can disperse over very long distances, and we provide the first genetic evidence that their parasitoids may disperse as far, if not farther. The contrasting geographic population structures of host and parasitoid highlight the potential for geographic mosaics in this important symbiotic system. PMID:26876233

  5. Limited collaborative study of an optional method for the isolation of light filth from fig and fruit paste.

    PubMed

    Kvenberg, J E; Eisenberg, W V; King, A C

    1975-05-01

    The present official first action method for the isolation of light filth from fig and fruit paste, 44.083(a), occasionally yields excessive plant debris on filter papers, which causes difficulty in effectively counting insect filth. The proposed method provides the option of an additional flotation of trapped off material in a Corning percolator. This revision has been adopted as official first action as an alternative to 44.083(a). PMID:1141170

  6. Limbic Activity Modulation Guided by Functional Magnetic Resonance Imaging-Inspired Electroencephalography Improves Implicit Emotion Regulation.

    PubMed

    Keynan, Jackob N; Meir-Hasson, Yehudit; Gilam, Gadi; Cohen, Avihay; Jackont, Gilan; Kinreich, Sivan; Ikar, Limor; Or-Borichev, Ayelet; Etkin, Amit; Gyurak, Anett; Klovatch, Ilana; Intrator, Nathan; Hendler, Talma

    2016-09-15

    The amygdala has a pivotal role in processing traumatic stress; hence, gaining control over its activity could facilitate adaptive mechanism and recovery. To date, amygdala volitional regulation could be obtained only via real-time functional magnetic resonance imaging (fMRI), a highly inaccessible procedure. The current article presents high-impact neurobehavioral implications of a novel imaging approach that enables bedside monitoring of amygdala activity using fMRI-inspired electroencephalography (EEG), hereafter termed amygdala-electrical fingerprint (amyg-EFP). Simultaneous EEG/fMRI indicated that the amyg-EFP reliably predicts amygdala-blood oxygen level-dependent activity. Implementing the amyg-EFP in neurofeedback demonstrated that learned downregulation of the amyg-EFP facilitated volitional downregulation of amygdala-blood oxygen level-dependent activity via real-time fMRI and manifested as reduced amygdala reactivity to visual stimuli. Behavioral evidence further emphasized the therapeutic potential of this approach by showing improved implicit emotion regulation following amyg-EFP neurofeedback. Additional EFP models denoting different brain regions could provide a library of localized activity for low-cost and highly accessible brain-based diagnosis and treatment. PMID:26996601

  7. Imaging Caspase-3 Activation as a Marker of Apoptosis-Targeted Treatment Response in Cancer

    PubMed Central

    Chen, Delphine L.; Engle, Jacquelyn T.; Griffin, Elizabeth A.; Miller, J. Philip; Chu, Wenhua; Zhou, Dong; Mach, Robert H.

    2016-01-01

    Purpose We tested whether positron emission tomography (PET) with the caspase-3 targeted isatin analog [18F]WC-4-116 could image caspase-3 activation in response to an apoptosis-inducing anticancer therapy. Procedures [18F]WC-4-116 uptake was determined in etoposide-treated EL4 cells. Biodistribution studies with [18F]WC-4-116 and [18F]ICMT-18, a non-caspase-3-targeted tracer, as well as [18F]WC-4-116 microPET imaging assessed responses in Colo205 tumor bearing mice treated with death receptor 5 (DR5) targeted agonist antibodies. Immunohistochemical staining and enzyme assays confirmed caspase-3 activation. Two-way analysis of variance or Student’s t-test assessed for treatment-related changes in tracer uptake. Results [18F]WC-4-116 increased 8 ± 2-fold in etoposide-treated cells. The [18F]WC-4-116 %ID/g also increased significantly in tumors with high caspase-3 enzyme activity (p < 0.05). [18F]ICMT-18 tumor uptake did not differ in tumors with high or low caspase-3 enzyme activity. Conclusions [18F]WC-4-116 uptake in vivo reflects increased caspase-3 activation and may be useful for detecting caspase-3 mediated apoptosis treatment responses in cancer. PMID:25344147

  8. Propagation of Some Local Fig (Ficus carica L.) Cultivars by Hardwood Cuttings under the Field Conditions in Tunisia

    PubMed Central

    Aljane, Fateh; Nahdi, Sabrine

    2014-01-01

    This research was carried out in Southeast of Tunisia in 2009 and 2010, in order to study the propagation of six (Ficus carica L.) cultivars by using hardwood cuttings under the field conditions. The effect of the cultivars and the type of buds, shoots age, shoots length, and shoots diameter were recorded. Ten cuttings per cultivar and/or cutting types with three replications were planted in rooting unit. Percentage of root emergence and six morphological parameters of young fig plants were measured. Results showed that the responses of cuttings as fig nursery plants presented a high variability among the five cultivars. The most widely varied characters were % root emergence (RE) and cumulative growth of young plant (CG). The first one ranged from 10% to 90%, the second varied within 32 and 112 cm. Concerning the ‘‘BITHER” cultivar, 6 cutting types with different age, length, and diameter were evaluated. Results showed a great variation in % of root emergence (0–90%), length of nursery plant (3–77 cm), and number of roots/nursery plant (0–29 roots). The present research showed that the hardwood cutting of local fig cultivars can be propagated under field conditions in Southeast of Tunisia.

  9. Imaging large-scale cellular activity in spinal cord of freely behaving mice.

    PubMed

    Sekiguchi, Kohei J; Shekhtmeyster, Pavel; Merten, Katharina; Arena, Alexander; Cook, Daniela; Hoffman, Elizabeth; Ngo, Alexander; Nimmerjahn, Axel

    2016-01-01

    Sensory information from mechanoreceptors and nociceptors in the skin plays key roles in adaptive and protective motor behaviours. To date, very little is known about how this information is encoded by spinal cord cell types and their activity patterns, particularly under freely behaving conditions. To enable stable measurement of neuronal and glial cell activity in behaving mice, we have developed fluorescence imaging approaches based on two- and miniaturized one-photon microscopy. We show that distinct cutaneous stimuli activate overlapping ensembles of dorsal horn neurons, and that stimulus type and intensity is encoded at the single-cell level. In contrast, astrocytes show large-scale coordinated calcium responses to intense but not weak sensory inputs. Sensory-evoked activity is potently suppressed by anaesthesia. By revealing the cellular and computational logic of spinal cord networks under behaving conditions, our approach holds promise for better understanding of healthy and aberrant spinal cord processes. PMID:27121084

  10. Imaging large-scale cellular activity in spinal cord of freely behaving mice

    PubMed Central

    Sekiguchi, Kohei J.; Shekhtmeyster, Pavel; Merten, Katharina; Arena, Alexander; Cook, Daniela; Hoffman, Elizabeth; Ngo, Alexander; Nimmerjahn, Axel

    2016-01-01

    Sensory information from mechanoreceptors and nociceptors in the skin plays key roles in adaptive and protective motor behaviours. To date, very little is known about how this information is encoded by spinal cord cell types and their activity patterns, particularly under freely behaving conditions. To enable stable measurement of neuronal and glial cell activity in behaving mice, we have developed fluorescence imaging approaches based on two- and miniaturized one-photon microscopy. We show that distinct cutaneous stimuli activate overlapping ensembles of dorsal horn neurons, and that stimulus type and intensity is encoded at the single-cell level. In contrast, astrocytes show large-scale coordinated calcium responses to intense but not weak sensory inputs. Sensory-evoked activity is potently suppressed by anaesthesia. By revealing the cellular and computational logic of spinal cord networks under behaving conditions, our approach holds promise for better understanding of healthy and aberrant spinal cord processes. PMID:27121084

  11. Role of Fig1, a Component of the Low-Affinity Calcium Uptake System, in Growth and Sexual Development of Filamentous Fungi

    PubMed Central

    Cavinder, Brad

    2012-01-01

    The function of Fig1, a transmembrane protein of the low-affinity calcium uptake system (LACS) in fungi, was examined for its role in the growth and development of the plant pathogen Fusarium graminearum. The Δfig1 mutants failed to produce mature perithecia, and sexual development was halted prior to the formation of perithecium initials. The loss of Fig1 function also resulted in a reduced vegetative growth rate. Macroconidium production was reduced 70-fold in the Δfig1 mutants compared to the wild type. The function of the high-affinity calcium uptake system (HACS), comprised of the Ca2+ channels Mid1 and Cch1, was previously characterized for F. graminearum. To better understand the roles of the LACS and the HACS, Δfig1 Δmid1, Δfig1 Δcch1, and Δfig1 Δmid1 Δcch1 double and triple mutants were generated, and the phenotypes of these mutants were more severe than those of the Δfig1 mutants. Pathogenicity on wheat was unaffected for the Δfig1 mutants, but the Δfig1 Δmid1, Δfig1 Δcch1, and Δfig1 Δmid1 Δcch1 mutants, lacking both LACS and HACS functions, had reduced pathogenicity. Additionally, Δfig1 mutants of Neurospora crassa were examined and did not affect filamentous growth or female fertility in a Δfig1 mating type A strain, but the Δfig1 mating type a strain failed to produce fertile fruiting bodies. These results are the first report of Fig1 function in filamentous ascomycetes and expand its role to include complex fruiting body and ascus development. PMID:22635922

  12. Studies on the introduction and mobility of the maize Activator element in Arabidopsis thaliana and Daucus carota.

    PubMed Central

    Van Sluys, M A; Tempé, J; Fedoroff, N

    1987-01-01

    We have co-transformed carrot (Daucus carota) and Arabidopsis thaliana with an Agrobacterium tumefaciens non-tumorigenic T-DNA carrying the maize transposable element Activator (Ac) and an Agrobacterium rhizogenes Ri T-DNA. We present evidence that the Ac element transposes in transformed root or root-derived callus cultures of both species. We show that fertile plants can be regenerated from transformed, root-derived callus cultures of Arabidopsis, demonstrating the utility of the Ri plasmid for introducing the maize Ac element into plants. We also present evidence that Ac elements that excise from the transforming T-DNA early after transformation continue to be mobile in carrot root cultures. Images Fig. 2. Fig. 3. Fig. 4. Fig. 5. Fig. 6. Fig. 7. PMID:2832144

  13. Image

    2007-08-31

    The computer side of the IMAGE project consists of a collection of Perl scripts that perform a variety of tasks; scripts are available to insert, update and delete data from the underlying Oracle database, download data from NCBI's Genbank and other sources, and generate data files for download by interested parties. Web scripts make up the tracking interface, and various tools available on the project web-site (image.llnl.gov) that provide a search interface to the database.

  14. Through-wall imaging and characterization of human activity using ultrawideband (UWB) random noise radar

    NASA Astrophysics Data System (ADS)

    Lai, Chieh-Ping; Narayanan, Ram M.

    2005-05-01

    Recent terrorist activities and law-enforcement situations involving hostage situations underscore the need for effective through-wall imaging. Current building interior imaging systems are based on short-pulse waveforms, which require specially designed antennas to subdue unwanted ringing. In addition, periodically transmitted pulses of energy are easily recognizable by the intelligent adversary who may employ appropriate countermeasures to confound detection. A coherent polarimetric random noise radar architecture is being developed based on UWB technology and software defined radio, which has great promise in its ability to covertly image obscured targets. The main advantages of the random noise radar lie in two aspects: first, random noise waveform has an ideal "thumbtack" ambiguity function, i.e., its down range and cross range resolution can be separately controlled, thus providing unambiguous high resolution imaging at any distance; second, random noise waveform is inherently low probability of intercept (LPI) and low probability of detection (LPD), i.e., it is immune from detection, jamming, and interference. Thus, it is an ideal candidate sensor for covert imaging of obscured regions in hostile environments. The coherency in the system can be exploited to field a fully-polarimetric system that can take advantage of polarization features in target recognition. Moving personnel can also be detected using Doppler processing. Simulation studies are used to analyze backscattered signals from the walls, and humans and other targets behind the walls. Real-time data processing shows human activity behind the wall and human target tracking. The high resolution provides excellent multipath and clutter rejection.

  15. Body Image and Nutritional Status Are Associated with Physical Activity in Men and Women: The ELSA-Brasil Study

    PubMed Central

    Coelho, Carolina G.; Giatti, Luana; Molina, Maria D. C. B.; Nunes, Maria A. A.; Barreto, Sandhi M.

    2015-01-01

    The association of body image dissatisfaction and obesity with physical activity is likely to differ according to gender. To investigate this hypothesis, we conducted a cross-sectional study among the ELSA-Brasil cohort members aged 34–65 years (n = 13,286). The body image dissatisfaction was present even among normal weight individuals of both sexes and was associated with lesser chances of practicing moderate physical activity in women and intense physical activity in men. Men and women with central obesity were less prone to practice physical activity of high or moderate intensity. Overweight and obese men were more likely to report vigorous physical activity while obese women were less likely to report this level of physical activity. Body images as well as nutritional status are related to physical activity in both sexes, but the association with physical activity differs by gender. PMID:26035664

  16. Cooling rate of some active lavas determined using an orbital imaging spectrometer

    NASA Astrophysics Data System (ADS)

    Wright, Robert; Garbeil, Harold; Davies, Ashley G.

    2010-06-01

    The surface temperature of an active lava flow is an important physical property to measure. Through its influence on lava crystallinity, cooling exerts a fundamental control on lava rheology. Remotely sensed thermal radiance data acquired by multispectral sensors such as Landsat Thematic Mapper and the Terra Advanced Spaceborne Thermal Emission and Reflection Radiometer are of insufficient spectral and radiometric fidelity to allow for realistic determination of lava surface temperatures from Earth orbit. This paper presents results obtained from the analysis of active lava flows using hyperspectral data acquired by NASA's Earth Observing-1 Hyperion imaging spectrometer. The contiguous nature of the measured radiance spectrum in the 0.4-2.5 μm region means that, although sensor saturation most certainly occurs, unsaturated radiance data are always available from even the hottest, and most radiant, active lava flow surfaces. The increased number of wave bands available allows for the assumption of more complex flow surface temperature distributions in the radiance-to-temperature inversion processes. The technique is illustrated by using a hyperspectral image of the active lava lake at Erta Ale volcano, Ethiopia, a well-characterized calibration target, a time series of three Hyperion images of an active lava flow acquired during a 4 day period at Mount Etna, Sicily, as well as a lava flow erupted at Nyamuragira, Democratic Republic of Congo. The results provide insights into the temperature-radiance mixture modeling problem that will aid in the analysis of data acquired by future hyperspectral remote sensing missions, such as NASA's proposed HyspIRI mission.

  17. Early functional magnetic resonance imaging activations predict language outcome after stroke.

    PubMed

    Saur, Dorothee; Ronneberger, Olaf; Kümmerer, Dorothee; Mader, Irina; Weiller, Cornelius; Klöppel, Stefan

    2010-04-01

    An accurate prediction of system-specific recovery after stroke is essential to provide rehabilitation therapy based on the individual needs. We explored the usefulness of functional magnetic resonance imaging scans from an auditory language comprehension experiment to predict individual language recovery in 21 aphasic stroke patients. Subjects with an at least moderate language impairment received extensive language testing 2 weeks and 6 months after left-hemispheric stroke. A multivariate machine learning technique was used to predict language outcome 6 months after stroke. In addition, we aimed to predict the degree of language improvement over 6 months. 76% of patients were correctly separated into those with good and bad language performance 6 months after stroke when based on functional magnetic resonance imaging data from language relevant areas. Accuracy further improved (86% correct assignments) when age and language score were entered alongside functional magnetic resonance imaging data into the fully automatic classifier. A similar accuracy was reached when predicting the degree of language improvement based on imaging, age and language performance. No prediction better than chance level was achieved when exploring the usefulness of diffusion weighted imaging as well as functional magnetic resonance imaging acquired two days after stroke. This study demonstrates the high potential of current machine learning techniques to predict system-specific clinical outcome even for a disease as heterogeneous as stroke. Best prediction of language recovery is achieved when the brain activation potential after system-specific stimulation is assessed in the second week post stroke. More intensive early rehabilitation could be provided for those with a predicted poor recovery and the extension to other systems, for example, motor and attention seems feasible. PMID:20299389

  18. High-contrast active cavitation imaging technique based on multiple bubble wavelet transform.

    PubMed

    Lu, Shukuan; Xu, Shanshan; Liu, Runna; Hu, Hong; Wan, Mingxi

    2016-08-01

    In this study, a unique method that combines the ultrafast active cavitation imaging technique with multiple bubble wavelet transform (MBWT) for improving cavitation detection contrast was presented. The bubble wavelet was constructed by the modified Keller-Miksis equation that considered the mutual effect among bubbles. A three-dimensional spatial model was applied to simulate the spatial distribution of multiple bubbles. The effects of four parameters on the signal-to-noise ratio (SNR) of cavitation images were evaluated, including the following: initial radii of bubbles, scale factor in the wavelet transform, number of bubbles, and the minimum inter-bubble distance. And the other two spatial models and cavitation bubble size distributions were introduced in the MBWT method. The results suggested that in the free-field experiments, the averaged SNR of images acquired by the MBWT method was improved by 7.16 ± 0.09 dB and 3.14 ± 0.14 dB compared with the values of images acquired by the B-mode and single bubble wavelet transform (SBWT) methods. In addition, in the tissue experiments, the averaged cavitation-to-tissue ratio of cavitation images acquired by the MBWT method was improved by 4.69 ± 0.25 dB and 1.74± 0.29 dB compared with that of images acquired by B-mode and SBWT methods. PMID:27586732

  19. Observations of Io's Active Volcanoes from IRTF: Imaging and Occultation Lightcurves

    NASA Astrophysics Data System (ADS)

    Rathbun, J. A.; Spencer, J. R.

    2014-12-01

    We have been observing Ionian volcanism from NASA's Infrared Telescope Facility (IRTF) for more than two decades. The frequency of our observations increases dramatically when spacecraft are observing Io in order to complement the data returned by the spacecraft. The Japanese Space Agency's (JAXA) Hisaki (Sprint-A) mission recently observd the Jupiter system from earth orbit, monitoring the Io Plasma Torus and Jovian aurora. In order to investigate the possible influence of Io volcanism on the torus, we observed Io's volcanoes from the IRTF in Hawaii between September 2013 and May 2014. We imaged Io at 2.2, 3.5, and 4.8 microns in eclipse and reflected sunlight. We also observed Io during occultation by Jupiter, which allows us to locate and characterize individual volcanic eruptions, with greater spatial accuracy, on the Jupiter-facing hemisphere. The 2013 3.5 micron images of a sunlit Io showed no obvious bright volcanic features. However, further increases in spatial resolution is possible with shift-and-add processing of short exposure images. Preliminary occultation lightcurves from 2013 show moderate levels of activity at Kaneheliki/Janus and Loki, the two volcanic centers most often observed in occultation lightcurves. Loki was much brighter in 2013 than during the New Horizons flyby in 2007, but not as bright as during the Galileo era (see figure). From February 2014 through May 2014, due to a planned upgrade on the SPEX instrument and an unplanned required repair on the NSFCam2 instrument (both of which we have used previously), we exclusively used the CSHELL instrument as an imager. Unfortunately, CSHELL was not designed for imaging and has limited spatial resolution and photometric precision, complicating image analysis.

  20. Unmasking Silent Endothelial Activation in the Cardiovascular System Using Molecular Magnetic Resonance Imaging

    PubMed Central

    Belliere, Julie; Martinez de Lizarrondo, Sara; Choudhury, Robin P.; Quenault, Aurélien; Le Béhot, Audrey; Delage, Christine; Chauveau, Dominique; Schanstra, Joost P.; Bascands, Jean-Loup; Vivien, Denis; Gauberti, Maxime

    2015-01-01

    Endothelial activation is a hallmark of cardiovascular diseases, acting either as a cause or a consequence of organ injury. To date, we lack suitable methods to measure endothelial activation in vivo. In the present study, we developed a magnetic resonance imaging (MRI) method allowing non-invasive endothelial activation mapping in the vasculature of the main organs affected during cardiovascular diseases. In clinically relevant contexts in mice (including systemic inflammation, acute and chronic kidney diseases, diabetes mellitus and normal aging), we provided evidence that this method allows detecting endothelial activation before any clinical manifestation of organ failure in the brain, kidney and heart with an exceptional sensitivity. In particular, we demonstrated that diabetes mellitus induces chronic endothelial cells activation in the kidney and heart. Moreover, aged mice presented activated endothelial cells in the kidneys and the cerebrovasculature. Interestingly, depending on the underlying condition, the temporospatial patterns of endothelial activation in the vascular beds of the cardiovascular system were different. These results demonstrate the feasibility of detecting silent endothelial activation occurring in conditions associated with high cardiovascular risk using molecular MRI. PMID:26379785

  1. Unmasking Silent Endothelial Activation in the Cardiovascular System Using Molecular Magnetic Resonance Imaging.

    PubMed

    Belliere, Julie; Martinez de Lizarrondo, Sara; Choudhury, Robin P; Quenault, Aurélien; Le Béhot, Audrey; Delage, Christine; Chauveau, Dominique; Schanstra, Joost P; Bascands, Jean-Loup; Vivien, Denis; Gauberti, Maxime

    2015-01-01

    Endothelial activation is a hallmark of cardiovascular diseases, acting either as a cause or a consequence of organ injury. To date, we lack suitable methods to measure endothelial activation in vivo. In the present study, we developed a magnetic resonance imaging (MRI) method allowing non-invasive endothelial activation mapping in the vasculature of the main organs affected during cardiovascular diseases. In clinically relevant contexts in mice (including systemic inflammation, acute and chronic kidney diseases, diabetes mellitus and normal aging), we provided evidence that this method allows detecting endothelial activation before any clinical manifestation of organ failure in the brain, kidney and heart with an exceptional sensitivity. In particular, we demonstrated that diabetes mellitus induces chronic endothelial cells activation in the kidney and heart. Moreover, aged mice presented activated endothelial cells in the kidneys and the cerebrovasculature. Interestingly, depending on the underlying condition, the temporospatial patterns of endothelial activation in the vascular beds of the cardiovascular system were different. These results demonstrate the feasibility of detecting silent endothelial activation occurring in conditions associated with high cardiovascular risk using molecular MRI. PMID:26379785

  2. On the Active Region Bright Grains Observed in the Transition Region Imaging Channels of IRIS

    NASA Astrophysics Data System (ADS)

    Skogsrud, H.; Rouppe van der Voort, L.; De Pontieu, B.

    2016-02-01

    The Interface Region Imaging Spectrograph (IRIS) provides spectroscopy and narrow band slit-jaw (SJI) imaging of the solar chromosphere and transition region at unprecedented spatial and temporal resolutions. Combined with high-resolution context spectral imaging of the photosphere and chromosphere as provided by the Swedish 1 m Solar Telescope (SST), we can now effectively trace dynamic phenomena through large parts of the solar atmosphere in both space and time. IRIS SJI 1400 images from active regions, which primarily sample the transition region with the Si iv 1394 and 1403 Å lines, reveal ubiquitous bright “grains” which are short-lived (two to five minute) bright roundish small patches of sizes 0.″5-1.″7 that generally move limbward with velocities up to about 30 km s-1. In this paper, we show that many bright grains are the result of chromospheric shocks impacting the transition region. These shocks are associated with dynamic fibrils (DFs), most commonly observed in Hα. We find that the grains show the strongest emission in the ascending phase of the DF, that the emission is strongest toward the top of the DF, and that the grains correspond to a blueshift and broadening of the Si iv lines. We note that the SJI 1400 grains can also be observed in the SJI 1330 channel which is dominated by C ii lines. Our observations show that a significant part of the active region transition region dynamics is driven from the chromosphere below rather than from coronal activity above. We conclude that the shocks that drive DFs also play an important role in the heating of the upper chromosphere and lower transition region.

  3. Radioiodinated DPA-713 Imaging Correlates with Bactericidal Activity of Tuberculosis Treatments in Mice

    PubMed Central

    Ordonez, Alvaro A.; Pokkali, Supriya; DeMarco, Vincent P.; Klunk, Mariah; Mease, Ronnie C.; Foss, Catherine A.; Pomper, Martin G.

    2014-01-01

    Current tools for monitoring response to tuberculosis treatments have several limitations. Noninvasive biomarkers could accelerate tuberculosis drug development and clinical studies, but to date little progress has been made in developing new imaging technologies for this application. In this study, we developed pulmonary single-photon emission computed tomography (SPECT) using radioiodinated DPA-713 to serially monitor the activity of tuberculosis treatments in live mice, which develop necrotic granulomas and cavitary lesions. C3HeB/FeJ mice were aerosol infected with Mycobacterium tuberculosis and administered either a standard or a highly active bedaquiline-containing drug regimen. Serial 125I-DPA-713 SPECT imaging was compared with 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) and standard microbiology. Ex vivo studies were performed to characterize and correlate DPA-713 imaging with cellular and cytokine responses. Pulmonary 125I-DPA-713 SPECT, but not 18F-FDG PET, was able to correctly identify the bactericidal activities of the two tuberculosis treatments as early as 4 weeks after the start of treatment (P < 0.03). DPA-713 readily penetrated the fibrotic rims of necrotic and cavitary lesions. A time-dependent decrease in both tumor necrosis factor alpha (TNF-α) and interferon gamma (IFN-γ) levels was observed with treatments, with 125I-DPA-713 SPECT correlating best with tissue TNF-α levels (ρ = 0.94; P < 0.01). 124I-DPA-713 was also evaluated as a PET probe and demonstrated a 4.0-fold-higher signal intensity in the infected tuberculous lesions than uninfected controls (P = 0.03). These studies provide proof of concept for application of a novel noninvasive imaging biomarker to monitor tuberculosis treatments, with the potential for application for humans. PMID:25403669

  4. Radioiodinated DPA-713 imaging correlates with bactericidal activity of tuberculosis treatments in mice.

    PubMed

    Ordonez, Alvaro A; Pokkali, Supriya; DeMarco, Vincent P; Klunk, Mariah; Mease, Ronnie C; Foss, Catherine A; Pomper, Martin G; Jain, Sanjay K

    2015-01-01

    Current tools for monitoring response to tuberculosis treatments have several limitations. Noninvasive biomarkers could accelerate tuberculosis drug development and clinical studies, but to date little progress has been made in developing new imaging technologies for this application. In this study, we developed pulmonary single-photon emission computed tomography (SPECT) using radioiodinated DPA-713 to serially monitor the activity of tuberculosis treatments in live mice, which develop necrotic granulomas and cavitary lesions. C3HeB/FeJ mice were aerosol infected with Mycobacterium tuberculosis and administered either a standard or a highly active bedaquiline-containing drug regimen. Serial (125)I-DPA-713 SPECT imaging was compared with (18)F-fluorodeoxyglucose ((18)F-FDG) positron emission tomography (PET) and standard microbiology. Ex vivo studies were performed to characterize and correlate DPA-713 imaging with cellular and cytokine responses. Pulmonary (125)I-DPA-713 SPECT, but not (18)F-FDG PET, was able to correctly identify the bactericidal activities of the two tuberculosis treatments as early as 4 weeks after the start of treatment (P < 0.03). DPA-713 readily penetrated the fibrotic rims of necrotic and cavitary lesions. A time-dependent decrease in both tumor necrosis factor alpha (TNF-α) and interferon gamma (IFN-γ) levels was observed with treatments, with (125)I-DPA-713 SPECT correlating best with tissue TNF-α levels (ρ = 0.94; P < 0.01). (124)I-DPA-713 was also evaluated as a PET probe and demonstrated a 4.0-fold-higher signal intensity in the infected tuberculous lesions than uninfected controls (P = 0.03). These studies provide proof of concept for application of a novel noninvasive imaging biomarker to monitor tuberculosis treatments, with the potential for application for humans. PMID:25403669

  5. Molecular photoacoustic imaging of breast cancer using an actively targeted conjugated polymer

    PubMed Central

    Balasundaram, Ghayathri; Ho, Chris Jun Hui; Li, Kai; Driessen, Wouter; Dinish, US; Wong, Chi Lok; Ntziachristos, Vasilis; Liu, Bin; Olivo, Malini

    2015-01-01

    Conjugated polymers (CPs) are upcoming optical contrast agents in view of their unique optical properties and versatile synthetic chemistry. Biofunctionalization of these polymer-based nanoparticles enables molecular imaging of biological processes. In this work, we propose the concept of using a biofunctionalized CP for noninvasive photoacoustic (PA) molecular imaging of breast cancer. In particular, after verifying the PA activity of a CP nanoparticle (CP dots) in phantoms and the targeting efficacy of a folate-functionalized version of the same (folate-CP dots) in vitro, we systemically administered the probe into a folate receptor-positive (FR+ve) MCF-7 breast cancer xenograft model to demonstrate the possible application of folate-CP dots for imaging FR+ve breast cancers in comparison to CP dots with no folate moieties. We observed a strong PA signal at the tumor site of folate-CP dots-administered mice as early as 1 hour after administration as a result of the active targeting of the folate-CP dots to the FR+ve tumor cells but a weak PA signal at the tumor site of CP-dots-administered mice as a result of the passive accumulation of the probe by enhanced permeability and retention effect. We also observed that folate-CP dots produced ~4-fold enhancement in the PA signal in the tumor, when compared to CP dots. These observations demonstrate the great potential of this active-targeting CP to be used as a contrast agent for molecular PA diagnostic imaging in various biomedical applications. PMID:25609951

  6. Possible mechanisms of normal amylase activity in hyperlipemic pancreatitis.

    PubMed Central

    Mishkin, S.; Bates, J.; O'Hashi, J.; Schneider, P.; Sniderman, A. D.; Wolf, R. O.

    1976-01-01

    Lipemic serum from three patients with acute pancreatitis and type IV hyperlipemia was fractionated into very-low-density lipoproteins and clear serum. Amylase activity (determined by the Phadebas method) in the component fractions did not exceed that in the original lipemic serum. Addition of these fractions or VLDL and chylomicrons from asymptomatic patients with hyperlipemia to nonlipemic serum from patients with "routine acute pancreatitis" did not inhibit amylase activity or alter the electrophoretic mobility of amylase isoenzymes. Therefore the normal amylase activity often observed in hyperlipemic pancreatitis does not result from an inhibition of amylase activity by serum lipoproteins. Images FIG. 4 FIG. 5 PMID:206333

  7. Oligopeptide elicitor-mediated defense gene activation in cultured parsley cells.

    PubMed Central

    Hahlbrock, K; Scheel, D; Logemann, E; Nürnberger, T; Parniske, M; Reinold, S; Sacks, W R; Schmelzer, E

    1995-01-01

    We have used suspension-cultured parsley cells (Petroselinum crispum) and an oligopeptide elicitor derived from a surface glycoprotein of the phytopathogenic fungus Phytophthora megasperma f.sp. glycinea to study the signaling pathway from elicitor recognition to defense gene activation. Immediately after specific binding of the elicitor by a receptor in the plasma membrane, large and transient increases in several inorganic ion fluxes (Ca2+, H+, K+, Cl-) and H2O2 formation are the first detectable plant cell responses. These are rapidly followed by transient changes in the phosphorylation status of various proteins and by the activation of numerous defense-related genes, concomitant with the inactivation of several other, non-defense-related genes. A great diversity of cis-acting elements and trans-acting factors appears to be involved in elicitor-mediated gene regulation, similar to the apparently complex nature of the signal transduced intracellularly. With few exceptions, all individual defense responses analyzed in fungus-infected parsley leaves have been found to be closely mimicked in elicitor-treated, cultured parsley cells, thus validating the use of the elicitor/cell culture system as a valuable model system for these types of study. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 PMID:7753777

  8. Mars' Active Surface: Observing Changes with Orthorectified HiRISE Images

    NASA Astrophysics Data System (ADS)

    Mattson, S.; McEwen, A. S.; Ojha, L.; Bridges, N. T.; Kirk, R. L.; Howington-Kraus, E.; Mogk, N.

    2012-12-01

    Active processes on Mars have been observed and documented with high resolution images from orbit. The HiRISE camera, operating on MRO since 2006, acquires images of the surface of Mars at up to 25 cm pixel scale, and has stereo capability. The use of HiRISE stereo images to produce digital terrain models (DTMs) allows for orthorectification of the stereo pair and other images targeted over the same area. HiRISE DTMs typically have 1 or 2 m horizontal resolution with vertical precision on the order of 10's of cm. DTM production with HiRISE requires that the source stereo pair has similar lighting and minimal surface differences. However, there is no similar requirement for orthorectifying other images taken of the same area. Changes on the surface can then be measured accurately in the orthoimages as topographic distortions have been minimized. Time sequences of surface changes can be constructed from a series of orthoimages, providing essential data for understanding their rate and magnitude. Some of the current areas of study using HiRISE DTMs and orthoimages include recurring slope lineae (RSL) (McEwen et al., Science 333, 740, 2011), dune and ripple migration (Bridges et al., Nature 485, 339, 2012), seasonal frost changes, and gully activity. In some cases, DTMs from before and after significant surface movement can be compared to measure volumetric changes. The demand for HiRISE DTMs and orthoimages has led to advances in techniques for their production and analysis. Improved image processing and terrain editing tools result in better DTMs and orthoimages, as well as minimize the time required to produce them. We present here ongoing work to refine these techniques and develop new methods for generating orthoimage sequences, including orthorectification of the HiRISE 3-band color strip. Results are illustrated using series of orthoimages over dunes, RSL sites and other areas of Martian surface activity. HiRISE DTMs and orthoimages are released to the Planetary

  9. Noninvasive bioluminescence imaging of the dynamics of sanguinarine induced apoptosis via activation of reactive oxygen species.

    PubMed

    Wang, Yan; Zhang, Beilei; Liu, Wei; Dai, Yunpeng; Shi, Yaru; Zeng, Qi; Wang, Fu

    2016-04-19

    Most chemotherapeutic drugs exert their anti-tumor effects primarily by triggering a final pathway leading to apoptosis. Noninvasive imaging of apoptotic events in preclinical models would greatly facilitate the development of apoptosis-inducing compounds and evaluation of their therapeutic efficacy. Here we employed a cyclic firefly luciferase (cFluc) reporter to screen potential pro-apoptotic compounds from a number of natural agents. We demonstrated that sanguinarine (SANG) could induce apoptosis in a dose- and time-dependent manner in UM-SCC-22B head and neck cancer cells. Moreover, SANG-induced apoptosis was associated with the generation of reactive oxygen species (ROS) and activation of c-Jun-N-terminal kinase (JNK) and nuclear factor-kappaB (NF-κB) signal pathways. After intravenous administration with SANG in 22B-cFluc xenograft models, a dramatic increase of luminescence signal can be detected as early as 48 h post-treatment, as revealed by longitudinal bioluminescence imaging in vivo. Remarkable apoptotic cells reflected from ex vivo TUNEL staining confirmed the imaging results. Importantly, SANG treatment caused distinct tumor growth retardation in mice compared with the vehicle-treated group. Taken together, our results showed that SANG is a candidate anti-tumor drug and noninvasive imaging of apoptosis using cFluc reporter could provide a valuable tool for drug development and therapeutic efficacy evaluation. PMID:26968950

  10. Noninvasive bioluminescence imaging of the dynamics of sanguinarine induced apoptosis via activation of reactive oxygen species

    PubMed Central

    Dai, Yunpeng; Shi, Yaru; Zeng, Qi; Wang, Fu

    2016-01-01

    Most chemotherapeutic drugs exert their anti-tumor effects primarily by triggering a final pathway leading to apoptosis. Noninvasive imaging of apoptotic events in preclinical models would greatly facilitate the development of apoptosis-inducing compounds and evaluation of their therapeutic efficacy. Here we employed a cyclic firefly luciferase (cFluc) reporter to screen potential pro-apoptotic compounds from a number of natural agents. We demonstrated that sanguinarine (SANG) could induce apoptosis in a dose- and time-dependent manner in UM-SCC-22B head and neck cancer cells. Moreover, SANG-induced apoptosis was associated with the generation of reactive oxygen species (ROS) and activation of c-Jun-N-terminal kinase (JNK) and nuclear factor-kappaB (NF-κB) signal pathways. After intravenous administration with SANG in 22B-cFluc xenograft models, a dramatic increase of luminescence signal can be detected as early as 48 h post-treatment, as revealed by longitudinal bioluminescence imaging in vivo. Remarkable apoptotic cells reflected from ex vivo TUNEL staining confirmed the imaging results. Importantly, SANG treatment caused distinct tumor growth retardation in mice compared with the vehicle-treated group. Taken together, our results showed that SANG is a candidate anti-tumor drug and noninvasive imaging of apoptosis using cFluc reporter could provide a valuable tool for drug development and therapeutic efficacy evaluation. PMID:26968950

  11. Acoustically active liposome-nanobubble complexes for enhanced ultrasonic imaging and ultrasound-triggered drug delivery.

    PubMed

    Nguyen, An T; Wrenn, Steven P

    2014-01-01

    Ultrasound is well known as a safe, reliable imaging modality. A historical limitation of ultrasound, however, was its inability to resolve structures at length scales less than nominally 20 µm, which meant that classical ultrasound could not be used in applications such as echocardiography and angiogenesis where one requires the ability to image small blood vessels. The advent of ultrasound contrast agents, or microbubbles, removed this limitation and ushered in a new wave of enhanced ultrasound applications. In recent years, the microbubbles have been designed to achieve yet another application, namely ultrasound-triggered drug delivery. Ultrasound contrast agents are thus tantamount to 'theranostic' vehicles, meaning they can do both therapy (drug delivery) and imaging (diagnostics). The use of ultrasound contrast agents as drug delivery vehicles, however, is perhaps less than ideal when compared to traditional drug delivery vehicles (e.g., polymeric microcapsules and liposomes) which have greater drug carrying capacities. The drawback of the traditional drug delivery vehicles is that they are not naturally acoustically active and cannot be used for imaging. The notion of a theranostic vehicle is sufficiently intriguing that many attempts have been made in recent years to achieve a vehicle that combines the echogenicity of microbubbles with the drug carrying capacity of liposomes. The attempts can be classified into three categories, namely entrapping, tethering, and nesting. Of these, nesting is the newest-and perhaps the most promising. PMID:24459007

  12. Mid-infrared, broadly tunable, active hyperspectral imaging system for the detection of gaseous hydrocarbon species

    NASA Astrophysics Data System (ADS)

    Stothard, David J. M.; Rae, Cameron F.; Ross, Mark; Dunn, Malcolm H.

    2007-10-01

    We describe a compact mid-infrared active spectroscopic imaging system for the rapid, stand-off detection of gas / chemical agents. Based upon the back-scatter absorption gas imaging (BAGI) technique, the system utilises a miniaturised, extremely efficient all solid state intracavity optical parametric oscillator (OPO) as the imaging illumination source. The OPO produces up to 250mW of tunable radiation in the signal and idler fields over the range 1.3-4.5μm, for a diode pump power of only 3W. Due to the nature of the nonlinear crystal employed within the OPO, the system can be tuned across its spectral range in ~1 second. We obviate the very high cost and complexity of a cooled MCT or InSb video array by raster-scanning the collimated illumination beam over the area of interest and reconstructing the image by sampling the back-scattered radiation with a single element MCT photo-detector at each pixel point. This approach also improves the ultimate signal to noise ratio. Video-like frame rates of 10 f.p.s. have been demonstrated via this technique. The range limit of the instrument is currently <10 meters which is limited by the detector we currently employ. We demonstrate how the system has been used to detect, in real time, leaks of multi-species hydrocarbon gases.

  13. First evidence of phase-contrast imaging with laboratory sources and active pixel sensors

    NASA Astrophysics Data System (ADS)

    Olivo, A.; Arvanitis, C. D.; Bohndiek, S. E.; Clark, A. T.; Prydderch, M.; Turchetta, R.; Speller, R. D.

    2007-11-01

    The aim of the present work is to achieve a first step towards combining the advantages of an innovative X-ray imaging technique—phase-contrast imaging (XPCi)—with those of a new class of sensors, i.e. CMOS-based active pixel sensors (APSs). The advantages of XPCi are well known and include increased image quality and detection of details invisible to conventional techniques, with potential application fields encompassing the medical, biological, industrial and security areas. Vanilla, one of the APSs developed by the MI-3 collaboration (see http://mi3.shef.ac.uk), was thoroughly characterised and an appropriate scintillator was selected to provide X-ray sensitivity. During this process, a set of phase-contrast images of different biological samples was acquired by means of the well-established free-space propagation XPCi technique. The obtained results are very encouraging and are in optimum agreement with the predictions of a simulation recently developed by some of the authors thus further supporting its reliability. This paper presents these preliminary results in detail and discusses in brief both the background to this work and its future developments.

  14. Improved edge detection for object segmentation in ultrasound images using Active Shape Models

    NASA Astrophysics Data System (ADS)

    Arámbula Cosío, F.; Acosta, Hèctor G.; Conde, Edgar

    2015-01-01

    We report a new method for adjusting the points of an active shape model (ASM) to the edge of an object, on a grey level image. The method is based on the original iterative search for an optimum location of each point of the ASM, along the normal direction to the model boundary. In this work we determine the optimum location of the model boundary point through minimization of the error (euclidean distance) between a profile of pixels sampled along the normal direction, and its projection on the principal component axes, obtained from a training set of normal pixel profiles, located at the edge of the object. We validated our method on ultrasound images of the prostate and photographs of the left hand. Significant improvements were observed in the segmentation of the ultrasound images, with reference to the original ASM method of adjustment, while no significant improvement was observed for the photographs. Our method produced a mean error of 4.58 (mm) between corresponding expert and automatically annotated contours of the ultrasound images of the prostate, and 3.12 (mm) of mean error for the photographs of the left hand.

  15. A non-contact technique for measuring eccrine sweat gland activity using passive thermal imaging.

    PubMed

    Krzywicki, Alan T; Berntson, Gary G; O'Kane, Barbara L

    2014-10-01

    An approach for monitoring eccrine sweat gland activity using high resolution Mid-Wave Infrared (MWIR) imaging (3-5 μm wave band) is described. This technique is non-contact, passive, and provides high temporal and spatial resolution. Pore activity was monitored on the face and on the volar surfaces of the distal and medial phalanges of the index and middle fingers while participants performed a series of six deep inhalation and exhalation exercises. Two metrics called the Pore Activation Index (PAI) and Pore Count (PC) were defined as size-weighted and unweighted measures of active sweat gland counts respectively. PAI transient responses on the finger tips were found to be positively correlated to Skin Conductance Responses (SCRs). PAI responses were also observed on the face, although the finger sites appeared to be more responsive. Results indicate that thermal imaging of the pore response may provide a useful, non-contact, correlate measure for electrodermal responses recorded from related sites. PMID:24956027

  16. Laser active imaging-guided anti-tank missile system small-scale integration design

    NASA Astrophysics Data System (ADS)

    Yan, Mingliang; Shan, Xiangqian; Qu, Zhou

    2010-10-01

    At present, the domestic and international third-generation anti-tank missiles, laser-guided missiles are mostly divided into active laser-guided and laser semi-active guidance, this guidance system, there are vulnerable to electronic interference, can not be fully realized after launching deficiencies. Article based on this, an in-depth understanding of imaging-guided laser-active working principle, based on the pairs of third-generation anti-tank missile guidance system, boldly proposed to improve the anti-tank missiles, laser-active small-scale integration of imaging guidance system design, the main purpose is to improve a certain type of The optical target missile, TV angle measurement, laser-guided instruction transmission means, so that anti-tank missiles to achieve forward-looking, the next obstacle avoidance TV and multi-functional integration of the entire after launching smart missiles, and in theory be able to study the new antitank missiles play a certain reference.

  17. Imaging the magmatic system of Newberry Volcano using Joint active source and teleseismic tomography

    NASA Astrophysics Data System (ADS)

    Heath, Benjamin A.; Hooft, Emilie E. E.; Toomey, Douglas R.; Bezada, Maximiliano J.

    2015-12-01

    In this paper, we combine active and passive source P wave seis