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Kenan Buldurun - One of the best experts on this subject based on the ideXlab platform.

Roger Daley - One of the best experts on this subject based on the ideXlab platform.

  • recovery of the one and two dimensional windfields from Chemical Constituent observations using the Constituent transport equation and an extended kalman filter
    Meteorology and Atmospheric Physics, 1996
    Co-Authors: Roger Daley
    Abstract:

    The recovery of windfields from Chemical Constituents is a difficult, but potentially rewarding inverse problem. Advanced data assimilation methods, such as the extended Kalman filter, are theoretically capable of performing this task; but, at this time, little work has been undertaken. Daley (1994) constructed a one-dimensional extended Kalman filter (EKF) system to examine this problem. This work is extended here to include a more systematic examination of the one-dimensional case, together with experiments with non-divergent two-dimensional flow. The emphasis is on determining when wind recovery is likely to be successful or unsuccessful.

  • estimating the wind field from Chemical Constituent observations experiments with a one dimensional extended kalman filter
    Monthly Weather Review, 1995
    Co-Authors: Roger Daley
    Abstract:

    Abstract Modern data assimilation algorithms such as the four-dimensional variational algorithm or the extended Kalman filter (EKF) can, in theory, estimate the wind field from Chemical Constituent observations. This seems to be possible because of the wind-Constituent coupling in the Chemical transport equation. This paper examines this possibility by applying an EKF to the one-dimensional Constituent transport equation and to a prognostic, linear wind model. Generally, both transport and wind models are assumed to be perfect. Tangent linear (TLM) and adjoint models for the Chemical transport model are developed and examined. A set of preliminary experiments was performed assuming perfect winds and examining the propagation of Constituent errors. For this case, it was shown that the analysis of the Constituent in zones of strong convergence can only be determined from nearby observations inside the zone; but the situation is much more favorable in divergent zones. This was shown to be consistent with obs...

Ercan Bursal - One of the best experts on this subject based on the ideXlab platform.

Reinaldo Nóbrega De Almeida - One of the best experts on this subject based on the ideXlab platform.

  • anxiolytic like activity and gc ms analysis of r limonene fragrance a natural compound found in foods and plants
    Pharmacology Biochemistry and Behavior, 2013
    Co-Authors: Naiana G P B Lima, Damião Pergentino De Sousa, Flavia Pimenta, Mateus Feitosa Alves, Fabio Santos De Souza, Rui Oliveira Macedo, Ricardo Barros Cardoso, Liana Clebia Soares Lima De Morais, Margareth De Fatima Formiga Melo Diniz, Reinaldo Nóbrega De Almeida
    Abstract:

    Abstract The traditional use of essential oils in aromatherapy has offered numerous health benefits. However, few scientific studies have been conducted with these oils to confirm their therapeutic efficacy. (+)-Limonene is a Chemical Constituent of various bioactive essential oils. The present study reports on the anxiolytic-like effects of (+)-limonene in an elevated maze model of anxiety in mice. At concentrations of 0.5% and 1.0%, (+)-limonene, administered to mice by inhalation, significantly modified all the parameters evaluated in the elevated plus maze test. The pharmacological effect of inhaled (+)-limonene (1%) was not blocked by flumazenil. Analysis of (+)-limonene using gas chromatography–mass spectrometry (GC–MS) showed its volatility to be high. These data suggest possible connections between the volatility of (+)-limonene and its anxiolytic-like effect on the parameters evaluated in the elevated plus maze test. The data indicate that (+)-limonene could be used in aromatherapy as an antianxiety agent.

  • pharmacological activity of r pulegone a Chemical Constituent of essential oils
    Zeitschrift für Naturforschung C, 2011
    Co-Authors: Damião Pergentino De Sousa, Franklin F F Nobrega, Maria R V De Lima, Reinaldo Nóbrega De Almeida
    Abstract:

    Medicinal plants contain a diversity of biologically active compounds that comprise several Chemical classes, including terpenes, saponinic glycosides, steroids, alkaloids, and fl avonoids ( Liang and Fang, 2006; Da Silva et al., 2006; De Sousa and De Almeida, 2005). Some of these compounds, primarily monoterpenes, are found in essential oils extracted from plants. Essential oils have distinctive fragrances and/or fl avours and are used in cosmetic as well as medical applications. To this point, many of these oils exhibit biological properties (Craveiro et al., 1981), such as spasmolytic (Lis-Balchin and Hart, 1999), anxiolytic (Pultrini et al., 2006), antinociceptive (Santos et al., 2005), and anticonvulsant (Almeida et al., 2003; De Almeida et al., 2011) activities. Monoterpenes and other Chemical compounds found in essential oils are structurally simple molecules, but the recently reported studies of their pharmacological properties (De Sousa et al., 2007a, b, c; De Sousa, 2011; Amaral et al., 2007; Silva et al., 2007; De Almeida et al., 2008) indicate that they have the complex profi le of psychoactive drugs. (R)-(+)-Pulegone is a monoterpene found in essential oils from plants of the Labiatae family. In nature, pulegone occurs in both (+) and (–) forms. Dextrorotatory pulegone is obtained from oils from Mentha pulegium (pennyroyal), M. longifolia (horsemint), and others. Levorotatory pulegone is the major Constituent of Agastache formosanum (hummingbird mint) oil (Kocovský et al., 1986). Pulegone is also present in essential oils that are known to be bioactive, such as the analgesic oil extracted from the Chinese herb Shizonepeta tenuifolia Briq. (Yamahara et al., 1980). In our earlier studies, the structure-activity relationship of the analogues of rotundifolone, a monoterpene isolated from the essential oil of the leaves of Mentha x villosa (mojito mint), was investigated. In preliminary investigations, the monoterpene (R)-(+)-pulegone presented signifi cant antinociceptive activity in the acetic acid-induced writhing test (De Sousa et al., 2007c). This observation was further studied in the current work by evaluating the impact of (R)-(+)pulegone on the central nervous system (CNS) Pharmacological Activity of (R)-(+)-Pulegone, a Chemical Constituent of Essential Oils Damiao P. de Sousa, Franklin F. F. Nobrega, Maria R. V. de Lima, and Reinaldo N. de Almeida*

  • pharmacological activity of r pulegone a Chemical Constituent of essential oils
    Zeitschrift für Naturforschung C, 2011
    Co-Authors: Damião Pergentino De Sousa, Franklin F F Nobrega, Maria R V De Lima, Reinaldo Nóbrega De Almeida
    Abstract:

    (R)-(+)-Pulegone is a monoterpene found in essential oils from plants of the Labiatae family. This compound is a major Constituent of Agastache formosanum oil. In this study, the effect of (R)-(+)-pulegone on the central nervous system was evaluated. (R)-(+)-Pulegone caused a significant decrease in ambulation and an increase in pentobarbital-induced sleeping time in mice, indicating a central depressant effect. (+)-Pulegone also significantly increased the latency of convulsions as assessed by the pentylenetetrazole (PTZ) method. The antinociceptive properties of this monoterpene were studied in Chemical and thermal models of nociception. Chemical nociception induced in the first and second phase of the subplantar formalin test was significantly inhibited by (R)-(+)-pulegone and was not blocked by naloxone. Thermal nociception was also significantly inhibited while (R)-(+)-pulegone increased the reaction latency of the mice in the hot plate test. These results suggest that (R)-(+)-pulegone is a psychoactive compound and has the profile of an analgesic drug.

Abdülmelik Aras - One of the best experts on this subject based on the ideXlab platform.