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Sample records for astrophytum myriostigma lemaire

  1. Lemaire extraarticular plasty in anterolateral knee instability

    PubMed Central

    Paús, Vicente; Graieb, Ariel; Torrengo, Federico

    2017-01-01

    Anterolateral instability of the knee results from injury to the lateral capsular complex and the anterior cruciate ligament (ACL), and it should not be considered an isolated injury. Over the past years these structures have received renewed interest. The anterolateral ligament (ALL) recently described extends from the lateral side of the lateral femoral condyle to the antero-lateral edge of the tibia, and it is supposed to play a major role in anterolateral stability. ACL extra-articular tenodesis, initially developed as a single procedure, is now complementary to intra-articular plasty. Our indications are: pure rotational instability, symptomatic instability in non-athletes, and revision surgery. Lemaire-type plasty and post-opeartive care are described in detail. We suggest thorough patient history and clinical examination prior to surgical decision. Lemaire-type plasty effectively controls anterolateral instability.

  2. A tale of two cacti-the complex relationship between peyote (Lophophora williamsii) and endangered star cactus (Astrophytum asterias)

    Treesearch

    M. Terry; D. Price; J. Poole

    2007-01-01

    Astrophytum asterias, commonly called star cactus, is a federally listed endangered cactus endemic to the Tamaulipan thornscrub ecoregion of extreme southern Texas, USA, and Tamaulipas and Nuevo Leon, Mexico. Only three metapopulations totaling less than 4000 plants are presently known in Texas. Star cactus, known locally as “star peyote”, is highly...

  3. Hypoglycemic effect of Opuntia streptacantha Lemaire in NIDDM.

    PubMed

    Frati-Munari, A C; Gordillo, B E; Altamirano, P; Ariza, C R

    1988-01-01

    To assess the hypoglycemic effect of the nopal Opuntia streptacantha Lemaire (O. streptacantha Lem.), three groups of patients with non-insulin-dependent diabetes mellitus (NIDDM) were studied. Group one (16 patients) ingested 500 g of broiled nopal stems. Group 2 (10 patients) received only 400 ml of water as a control test. Three tests were performed on group 3 (6 patients): one with nopal, a second with water, and a third with ingestion of 500 g broiled squash. Serum glucose and insulin levels were measured at 0, 60, 120, and 180 min. After the intake of O. streptacantha Lem., serum glucose and serum insulin levels decreased significantly in groups 1 and 3, whereas no similar changes were noticed in group 2. The mean reduction of glucose reached 17.6 +/- 2.2% of basal values at 180 min in group 1 and 16.2 +/- 1.8% in group 3; the reduction of serum insulin at 180 min reached 50.2 +/- 8.0% in group 1 and 40.3 +/- 12.4% in group 3. This study shows that the stems of O. streptacantha Lem. cause a hypoglycemic effect in patients with NIDDM. The mechanism of this effect is unknown, but an increased insulin sensitivity is suggested.

  4. Clinical evaluation of the LeMaire anterior cruciate [correction of concrete] ligament lateral substitution procedure. A quality audit of the Leicester modification.

    PubMed

    Thomas, O L; Oni, O O; Howard, L

    1998-07-01

    The results of a modified LeMaire anterior cruciate [corrected] ligament (ACL) lateral substitution procedure have been assessed using a variety of methods. Of the patients, 87.5 per cent obtained a satisfactory result 3-4 years after the operation. The post-operative morbidity was relatively minor.

  5. [Injuries of the medial collateral ligament and anterior cruciate ligament of the knee joint and Lemaire surgical functional treatment. Long-term outcome].

    PubMed

    Schmid, F

    1996-06-01

    The present paper reports the results of 112 extraarticular ligamento-plasties performed on the knee with the procedure proposed by Lemaire. The series includes isolated tears of the anterior cruciate and medical collateral ligament as well as combined tears of both ligaments. The clinical and radiological results with a mean follow-up time of 11.5 years are compared with the results obtained in a first assessment 8 years ago. Good clinical results are in contrast with increasing osteoarthrosis in 1/3 of the knees radiologically assessed. The operation for a torn anterior cruciate ligament should be performed as soon as possible to avoid secondary meniscal lesions with subsequent severe osteoarthrosis. Presence or absence of arthrotic signs in the X-rays mainly determine the long-term result after ligamento-plasties of the knee. The Lemaire plasties are well tolerated even by elderly still active people and need little postoperative care.

  6. The scientific rationale for lateral tenodesis augmentation of intra-articular ACL reconstruction using a modified 'Lemaire' procedure.

    PubMed

    Williams, Andy; Ball, Simon; Stephen, Jo; White, Nathan; Jones, Mary; Amis, Andrew

    2017-04-01

    The purpose of this work was to develop the rationale for adding a lateral extra-articular tenodesis to an ACL reconstruction in a knee with an injury that included both the ACL and anterolateral structures, and to show the early clinical picture. The paper includes a review of recent anatomical and biomechanical studies of the anterolateral aspect of the knee. It then provides a detailed description of a modified Lemaire tenodesis technique. A short-term clinical follow-up of a case and control group was performed, with two sequential groups of patients treated by isolated ACL reconstruction, and by combined ACL plus lateral tenodesis. The anatomical and biomechanical literature guide the surgeon towards a procedure based on the ilio-tibial band. The clinical study found a reduction in pivot-shift instability in the group of patients with the combined procedure. The evidence suggests that it should be appropriate to add a lateral extra-articular procedure to an ACL reconstruction in selected cases, but it was concluded that further data are required before definitive guidelines on the use of a lateral tenodesis can be established. III.

  7. Hydrolysis of Agave fourcroydes Lemaire (henequen) leaf juice and fermentation with Kluyveromyces marxianus for ethanol production

    PubMed Central

    2014-01-01

    Background Carbon sources for biofuel production are wide-ranging and their availability depends on the climate and soil conditions of the land where the production chain is located. Henequen (Agave fourcroydes Lem.) is cultivated in Yucatán, Mexico to produce natural fibers from the leaves, and a juice containing fructans is produced during this process. Fructans can be hydrolyzed to fructose and glucose and metabolized into ethanol by appropriate yeasts. In Mexico, different Agave species provide the carbon source for (distilled and non-distilled) alcoholic beverage production using the stem of the plant, whilst the leaves are discarded. In this work, we investigated the effect of thermal acid and enzymatic hydrolysis of the juice on the amount of reducing sugars released. Growth curves were generated with the yeasts Saccharomyces cerevisiae and Kluyveromyces marxianus and fermentations were then carried out with Kluyveromyces marxianus to determine alcohol yields. Results With thermal acid hydrolysis, the greatest increase in reducing sugars (82.6%) was obtained using 5% H2SO4 at 100°C with a 30 min reaction time. Statistically similar results can be obtained using the same acid concentration at a lower temperature and with a shorter reaction time (60°C, 15 min), or by using 1% H2SO4 at 100°C with a 30 min reaction time. In the case of enzymatic hydrolysis, the use of 5.75, 11.47 and 22.82 U of enzyme did not produce significant differences in the increase in reducing sugars. Although both hydrolysis processes obtained similar results, the difference was observed after fermentation. Ethanol yields were 50.3 ± 4 and 80.04 ± 5.29% of the theoretical yield respectively. Conclusions Final reducing sugars concentrations obtained with both thermal acid and enzymatic hydrolysis were similar. Saccharomyces cerevisiae, a good ethanol producer, did not grow in the hydrolysates. Only Kluyveromyces marxianus was able to grow in them, giving a higher ethanol yield with the enzymatic hydrolysate. The leaves account for a non-negligible weight of the total agave plant biomass, so this work complements the knowledge already developed on agave fermentations by making it possible to produce ethanol from almost the entire plant (stem and leaves). PMID:24529165

  8. Hydrolysis of Agave fourcroydes Lemaire (henequen) leaf juice and fermentation with Kluyveromyces marxianus for ethanol production.

    PubMed

    Villegas-Silva, Pablo A; Toledano-Thompson, Tanit; Canto-Canché, Blondy B; Larqué-Saavedra, Alfonso; Barahona-Pérez, Luis F

    2014-02-14

    Carbon sources for biofuel production are wide-ranging and their availability depends on the climate and soil conditions of the land where the production chain is located. Henequen (Agave fourcroydes Lem.) is cultivated in Yucatán, Mexico to produce natural fibers from the leaves, and a juice containing fructans is produced during this process. Fructans can be hydrolyzed to fructose and glucose and metabolized into ethanol by appropriate yeasts. In Mexico, different Agave species provide the carbon source for (distilled and non-distilled) alcoholic beverage production using the stem of the plant, whilst the leaves are discarded. In this work, we investigated the effect of thermal acid and enzymatic hydrolysis of the juice on the amount of reducing sugars released. Growth curves were generated with the yeasts Saccharomyces cerevisiae and Kluyveromyces marxianus and fermentations were then carried out with Kluyveromyces marxianus to determine alcohol yields. With thermal acid hydrolysis, the greatest increase in reducing sugars (82.6%) was obtained using 5% H2SO4 at 100°C with a 30 min reaction time. Statistically similar results can be obtained using the same acid concentration at a lower temperature and with a shorter reaction time (60°C, 15 min), or by using 1% H2SO4 at 100°C with a 30 min reaction time. In the case of enzymatic hydrolysis, the use of 5.75, 11.47 and 22.82 U of enzyme did not produce significant differences in the increase in reducing sugars. Although both hydrolysis processes obtained similar results, the difference was observed after fermentation. Ethanol yields were 50.3 ± 4 and 80.04 ± 5.29% of the theoretical yield respectively. Final reducing sugars concentrations obtained with both thermal acid and enzymatic hydrolysis were similar. Saccharomyces cerevisiae, a good ethanol producer, did not grow in the hydrolysates. Only Kluyveromyces marxianus was able to grow in them, giving a higher ethanol yield with the enzymatic hydrolysate. The leaves account for a non-negligible weight of the total agave plant biomass, so this work complements the knowledge already developed on agave fermentations by making it possible to produce ethanol from almost the entire plant (stem and leaves).

  9. [Hypoglycemic action of different doses of nopal (Opuntia streptacantha Lemaire) in patients with type II diabetes mellitus].

    PubMed

    Frati-Munari, A C; Del Valle-Martínez, L M; Ariza-Andraca, C R; Islas-Andrade, S; Chávez-Negrete, A

    1989-01-01

    To assess the relationship between the doses of O. streptacantha Lem. and its acute hypoglycemic action in diabetics, eight patients with type II diabetes mellitus were studied. Four test were performed to each patient with the intake of: (a) 400 ml of water, (b) 100 g (c) 300 g and (d) 500 g of broiled stems of O. streptacantha Lem. Serum glucose was measured at 0, 60, 120 and 180 minutes. Maximal decrease of serum glucose was noticed at 180 minutes, with a mean of 2.3, 10, 30.1 and 46.7 mg/dl less than basal value with 0, 100, 300 and 500 g respectively (P = NS, less than 0.05, less than 0.001 and less than 0.001 respectively). A significant direct correlation (r = 0.690, P less than 0.001) was noticed between the doses and the hypoglycemic effect.

  10. 75 FR 67765 - Endangered and Threatened Species Permit Applications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-03

    ... captivity. The applicant's intended purpose is breeding, including (but not limited to) husbandry... purposes for the California condor (Gymnogyps californianus). The applicant intends to captive breed..., salvage, and collect seeds of the following rare plants: Star cactus (Astrophytum asterius), Johnston's...

  11. The effect of methanol extracts of tsao-ko (Amomum tsao-ko Crevost et Lemaire) on digestive enzyme and antioxidant activity in vitro, and plasma lipids and glucose and liver lipids in mice.

    PubMed

    Yu, Longquan; Shirai, Nobuya; Suzuki, Hiramitsu; Sugane, Nozomi; Hosono, Tsuyoshi; Nakajima, Yoshijiro; Kajiwara, Masahiro; Takatori, Kazuhiro

    2010-01-01

    Our previous study showed that tsao-ko intake can lower plasma and liver triacylglycerol (TG) concentrations and has hypoglycemic and antioxidant activity in mice. This study involved separating two major fractions (A and B) from the methanol extracts (MeX) of tsao-ko using silica gel column chromatography, and then determining the effect of the fractions in vivo and in vitro to clarify the most effective components of tsao-ko. An intake of MeX and A fraction statistically significantly reduced body lipids and plasma thiobarbitutic acid reactive substances (TBARS) concentrations compared with the control and inhibited lipase and alpha-glucosidase activities. These reductions were not observed in mice fed the B fraction and these inhibitions of B fraction were mild compared with MeX and A fraction. The plasma and liver TG concentrations of each fraction group did not show significant differences compared with the control. The [M-H](+) and maximum UV absorption of the A fraction were 291 m/z and 279 nm, respectively. The peak of A fraction appeared at a similar time to the epicatechin standard in the LC/MS/MS analysis and the MS/MS spectrum of the A fraction was similar to that of the epicatechin standard. It was concluded that the most effective component of tsao-ko for body lipid reduction and hypoglycemic and antioxidant activity was contained in the polar fraction and the evidence suggested that this component could be epicatechin. However, the strongest TG lowering components of tsao-ko may be methanol insoluble.

  12. Pre-release efficacy assessment of the leaf-mining moth Digitivalva delaireae (Lepidoptera: Glyphipterigidae), a potential biological control agent for Cape-ivy, Delairea odorata (Asteraceae), in western North America

    USDA-ARS?s Scientific Manuscript database

    The leaf-mining moth Digitivalva delaireae Gaedike & Kruger (Lepidoptera: Glyphipterigidae) is a potential biological control agent for the invasive vine Cape-ivy, Delairea odorata Lemaire (Asteraceae), in western North America, where two morphological varieties (stipulate and exstipulate) of Cape-i...

  13. Evidence for impulsive solar wind plasma penetration through the dayside magnetopause

    NASA Astrophysics Data System (ADS)

    Lundin, R.; Sauvaud, J.-A.; Rème, H.; Balogh, A.; Dandouras, I.; Bosqued, J. M.; Carlson, C.; Parks, G. K.; Möbius, E.; Kistler, L. M.; Klecker, B.; Amata, E.; Formisano, V.; Dunlop, M.; Eliasson, L.; Korth, A.; Lavraud, B.; McCarthy, M.

    2003-02-01

    This paper presents in situ observational evidence from the Cluster Ion Spectrometer (CIS) on Cluster of injected solar wind "plasma clouds" protruding into the day-side high-latitude magnetopause. The plasma clouds, presumably injected by a transient process through the day-side magnetopause, show characteristics implying a generation mechanism denoted impulsive penetration (Lemaire and Roth, 1978).

  14. Strategy Development in Children with Mathematical Disabilities: Insights from the Choice/No-Choice Method and the Chronological-Age/Ability-Level?Match Design

    ERIC Educational Resources Information Center

    Torbeyns, J.; Verschaffel, L.; Ghesquiere, P.

    2005-01-01

    This study investigated the strategy characteristics and development of children with mathematical disabilities (MD) in the domain of simple addition and subtraction, in terms of Lemaire and Siegler's model of strategic change, using the choice/no-choice method and the combined chronological-age (CA)/ability-level (AL)?match design. Four groups of…

  15. Efficiency and Adaptiveness of Multiple School-Taught Strategies in the Domain of Simple Addition

    ERIC Educational Resources Information Center

    Torbeyns, Joke; Verschaffel, Lieven; Ghesquiere, Pol

    2004-01-01

    This study investigated the fluency with which first-graders with strong, moderate, or weak mathematical abilities apply the decomposition-to-10 and tie strategy on almost-tie sums with bridge over 10. It also assessed children's memorized knowledge of additions up to 20. Children's strategies were analysed in terms of Lemaire and Siegler's model…

  16. Biomechanical Comparison of Anterolateral Procedures Combined With Anterior Cruciate Ligament Reconstruction.

    PubMed

    Inderhaug, Eivind; Stephen, Joanna M; Williams, Andy; Amis, Andrew A

    2017-02-01

    Anterolateral soft tissue structures of the knee have a role in controlling anterolateral rotational laxity, and they may be damaged at the time of anterior cruciate ligament (ACL) ruptures. To compare the kinematic effects of anterolateral operative procedures in combination with intra-articular ACL reconstruction for combined ACL plus anterolateral-injured knees. Controlled laboratory study. Twelve cadaveric knees were tested in a 6 degrees of freedom rig using an optical tracking system to record the kinematics through 0° to 90° of knee flexion with no load, anterior drawer, internal rotation, and combined loading. Testing was first performed in ACL-intact, ACL-deficient, and combined ACL plus anterolateral-injured (distal deep insertions of the iliotibial band and the anterolateral ligament [ALL] and capsule cut) states. Thereafter, ACL reconstruction was performed alone and in combination with the following: modified MacIntosh tenodesis, modified Lemaire tenodesis passed both superficial and deep to the lateral collateral ligament, and ALL reconstruction. Anterolateral grafts were fixed at 30° of knee flexion with both 20 and 40 N of tension. Statistical analysis used repeated-measures analyses of variance and paired t tests with Bonferroni adjustments. ACL reconstruction alone failed to restore native knee kinematics in combined ACL plus anterolateral-injured knees ( P < .05 for all). All combined reconstructions with 20 N of tension, except for ALL reconstruction ( P = .002-.01), restored anterior translation. With 40 N of tension, the superficial Lemaire and MacIntosh procedures overconstrained the anterior laxity in deep flexion. Only the deep Lemaire and MacIntosh procedures-with 20 N of tension-restored rotational kinematics to the intact state ( P > .05 for all), while the ALL underconstrained and the superficial Lemaire overconstrained internal rotation. The same procedures with 40 N of tension led to similar findings. In a combined ACL plus

  17. Anterolateral Tenodesis or Anterolateral Ligament Complex Reconstruction: Effect of Flexion Angle at Graft Fixation When Combined With ACL Reconstruction.

    PubMed

    Inderhaug, Eivind; Stephen, Joanna M; Williams, Andy; Amis, Andrew A

    2017-09-01

    Despite numerous technical descriptions of anterolateral procedures, knowledge is limited regarding the effect of knee flexion angle during graft fixation. To determine the effect of knee flexion angle during graft fixation on tibiofemoral joint kinematics for a modified Lemaire tenodesis or an anterolateral ligament (ALL) complex reconstruction combined with anterior cruciate ligament (ACL) reconstruction. Controlled laboratory study. Twelve cadaveric knees were mounted in a test rig with kinematics recorded from 0° to 90° flexion. Loads applied to the tibia were 90-N anterior translation, 5-N·m internal tibial rotation, and combined 90-N anterior force and 5-N·m internal rotation. Intact, ACL-deficient, and combined ACL plus anterolateral-deficient states were tested, and then ACL reconstruction was performed and testing was repeated. Thereafter, modified Lemaire tenodeses and ALL procedures with graft fixation at 0°, 30°, and 60° of knee flexion and 20-N graft tension were performed combined with the ACL reconstruction, and repeat testing was performed throughout. Repeated-measures analysis of variance and Bonferroni-adjusted t tests were used for statistical analysis. In combined ACL and anterolateral deficiency, isolated ACL reconstruction left residual laxity for both anterior translation and internal rotation. Anterior translation was restored for all combinations of ACL and anterolateral procedures. The combined ACL reconstruction and ALL procedure restored intact knee kinematics when the graft was fixed in full extension, but when the graft was fixed in 30° and 60°, the combined procedure left residual laxity in internal rotation ( P = .043). The combined ACL reconstruction and modified Lemaire procedure restored internal rotation regardless of knee flexion angle at graft fixation. When the combined ACL reconstruction and lateral procedure states were compared with the ACL-only reconstructed state, a significant reduction in internal rotation

  18. Tierra del Fuego, Argentina, South America

    NASA Technical Reports Server (NTRS)

    1991-01-01

    The Mitre Peninsula is the easternmost tip of Tierra del Fuego, Argentina, (54.5S, 65.5W). Early winter snow can be seen on this south tip of the Andes Mountains. These same mountains continue underwater to Antarctica. The Strait of Magellan, separating the South American mainland from Tierra del Fuego is off the scene to the north and west, but the Strait of LeMaire, separating Tierra del Fuego from the Isla de los Estados can be seen.

  19. Hypoglycemic effect of Opuntia cactus.

    PubMed

    Ibañez-Camacho, R; Roman-Ramos, R

    1979-01-01

    Nopal (Opuntia sp.) has been traditionally used by the Mexican population for the treatment of diabetes mellitus. The purpose of this work is to describe effects produced by directly liquified nopal and extracts from this plant in healthy and pancreatectomized rabbits. Preliminary results allow us to conclude that Opuntia streptacantha, Lemaire, has hypoglycemic properties when orally administered, in animals with experimentally induced diabetes as well as in healthy ones with physiologic hyperglycemia.

  20. "Nonempty" Gap Between Radiation Belts: The First Observations

    NASA Astrophysics Data System (ADS)

    Panasyuk, Mikhail

    2013-12-01

    The first space experiments carried out in 1958 by the scientific groups of James Van Allen (United States) on board the first Explorer satellites and Sergey Vernov (Soviet Union) on board the satellite Sputnik 3 led to the discovery of the Earth's radiation belts—the particles (mainly protons and electrons) captured by the magnetic field of the Earth. Two scientific groups independently came to the conclusion that the electrons in the geomagnetic trapping region fill two areas, inner and outer radiation belts, unlike the protons, which fill the whole trapping region [see, e.g., Lemaire, 2000].

  1. The population dynamics of an endemic collectible cactus

    NASA Astrophysics Data System (ADS)

    Mandujano, María C.; Bravo, Yolotzin; Verhulst, Johannes; Carrillo-Angeles, Israel; Golubov, Jordan

    2015-02-01

    Astrophytum is one of most collected genera in the cactus family. Around the world several species are maintained in collections and yearly, several plants are taken from their natural habitats. Populations of Astorphytum capricorne are found in the northern Chihuahuan desert, Mexico, and as many endemic cactus species, it has a highly restricted habitat. We conducted a demographic study from 2008 to 2010 of the northern populations found at Cuatro Ciénegas, Mexico. We applied matrix population models, included simulations, life table response experiments and descriptions of the population dynamics to evaluate the current status of the species, and detect key life table stages and demographic processes. Population growth rate decreased in both years and only 4% individual mortality can be attributed to looting, and a massive effort is needed to increase seedling recruitment and reduce adult mortality. The fate of individuals differed between years even having the same annual rainfall mainly in accentuated stasis, retrogression and high mortality in all size classes, which coupled with low seed production, no recruitment and collection of plants are the causes contributing to population decline, and hence, increase the risk in which A. capricorne populations are found. Reintroduction of seedlings and lowering adult mortality are urgently needed to revert the alarming demographic condition of A. capricorne populations.

  2. Coping with time scales in disease systems analysis: application to bone remodeling.

    PubMed

    Schmidt, Stephan; Post, Teun M; Peletier, Lambertus A; Boroujerdi, Massoud A; Danhof, Meindert

    2011-12-01

    In this study we demonstrate the added value of mathematical model reduction for characterizing complex dynamic systems using bone remodeling as an example. We show that for the given parameter values, the mechanistic RANK-RANKL-OPG pathway model proposed by Lemaire et al. (J Theor Biol 229:293-309, 2004) can be reduced to a simpler model, which can describe the dynamics of the full Lemaire model to very good approximation. The response of both models to changes in the underlying physiology and therapeutic interventions was evaluated in four physiologically meaningful scenarios: (i) estrogen deficiency/estrogen replacement therapy, (ii) Vitamin D deficiency, (iii) ageing, and (iv) chronic glucocorticoid treatment and its cessation. It was found that on the time scale of disease progression and therapeutic intervention, the models showed negligible differences in their dynamic properties and were both suitable for characterizing the impact of estrogen deficiency and estrogen replacement therapy, Vitamin D deficiency, ageing, and chronic glucocorticoid treatment and its cessation on bone forming (osteoblasts) and bone resorbing (osteoclasts) cells. It was also demonstrated how the simpler model could help in elucidating qualitative properties of the observed dynamics, such as the absence of overshoot and rebound, and the different dynamics of onset and washout.

  3. Diterbium hepta­nickel: a crystal structure redetermination

    PubMed Central

    Levytskyy, Volodymyr; Babizhetskyy, Volodymyr; Kotur, Bohdan; Smetana, Volodymyr

    2014-01-01

    The crystal structure of the title compound, Tb2Ni7, was redetermined from single-crystal X-ray diffraction data. In comparison with previous studies based on powder X-ray diffraction data [Lemaire et al. (1967). C. R. Acad. Sci. Ser. B, 265, 1280–1282; Lemaire & Paccard (1969). Bull. Soc. Fr. Mineral. Cristallogr. 92, 9–16; Buschow & van der Goot (1970). J. Less-Common Met. 22, 419–428], the present redetermination affords refined coordinates and anisotropic displacement parameters for all atoms. A partial occupation for one Tb atom results in the non-stoichiometric composition Tb1.962 (4)Ni7. The title compound adopts the Ce2Ni7 structure type and can also be derived from the CaCu5 structure type as an inter­growth structure. The asymmetric unit contains two Tb sites (both site symmetries 3m.) and five Ni sites (.m., mm2, 3m., 3m., -3m.). The two different coordination polyhedra of Tb are a Frank–Kasper polyhedron formed by four Tb and 12 Ni atoms and a pseudo Frank–Kasper polyhedron formed by two Tb and 18 Ni atoms. The four different coordination polyhedra of Ni are Frank–Kasper icosa­hedra formed by five Tb and seven Ni atoms, four Tb and eight Ni atoms, three Tb and nine Ni atoms, and six Tb and six Ni atoms, respectively. PMID:25249871

  4. Thermodynamical Framework for Ductile Damage and Plasticity

    NASA Astrophysics Data System (ADS)

    César de Sá, José M. A.; Andrade, Filipe X. C.; Andrade Pires, Francisco M.

    2010-05-01

    Many models employed for the prediction of plastic deformation rely exclusively on elastoplastic theories, disregarding significant effects of internal degradation [1]. Constitutive models based on the Continuum Damage Mechanics theory provide more realistic predictions since damage is taken into account as an internal variable. In the present contribution, Lemaire's model for ductile damage [2] is questioned under the assumption of the principle of maximum inelastic dissipation [3]. The model is enhanced with a nonlocal formulation where the damage variable is spatially averaged by means of an integral operator [4]. Thermodynamical admissibility of the nonlocal model is checked by applying the global version of the Clausius-Duhem inequality [5]. Results from numerical analysis show that the constitutive model is insensitive to spatial discretization.

  5. Effet de la turbidité sur la dégradation des pigments phytoplanctoniques dans l'estuaire de la GirondeEffect of turbidity on phytoplanktonic pigments degradation in the Gironde Estuary

    NASA Astrophysics Data System (ADS)

    Lemaire, Emmanuelle; Abril, Gwenaël; De Wit, Rutger; Etcheber, Henri

    In the Gironde Estuary, most part of phytoplanktonic material carried by the rivers is mineralised in the maximum turbidity zone (MTZ). In order to follow the degradation of the phytoplanktonic material into the MTZ, we developed an in vitro approach based on the monitoring of phytoplanktonic pigments. Algal material from two chlorophytes ( Scenedesmus suspicatus Chaudat and Chlamydomonas sp.) was incubated in the dark during 28 days into water samples from the Gironde estuary MTZ, at variable suspended solid concentrations (SPM) as well as in a sterilised turbid sample. First order decay constants of chlorophylls a and b and lutein increased by a factor 3 to 5 between SPM of 0 and 3 g l-1. The production of pheophytin a in the presence of particles and the lack of degradation in the sterilised turbid sample confirmed the effect of attached bacteria on the particles. To cite this article: E. Lemaire et al., C. R. Geoscience 334 (2002) 251-258.

  6. Mammillarinin: a new malonylated betacyanin from fruits of Mammillaria.

    PubMed

    Wybraniec, Sławomir; Nowak-Wydra, Barbara

    2007-10-03

    A new betacyanin endogenously occurring in fruits of nine Mammillaria species, i.e., M. roseo-alba (Boedecker), M. donatii (Berge), M. coronata (Scheidweiler), M. karwinskiana (Martius), M. gummifera (Engelmann), M. infernillensis (Craig), M. centricirrha (Lemaire), M. krameri (Muehlenpfordt), and M. magnimamma (Haworth), was studied by means of spectroscopic techniques. The betacyanin was identified as betanidin 5-O-(6'-O-malonyl)-beta-sophoroside for which the trivial name mammillarinin is proposed. In some Mammillaria species this compound was reported as a dominating pig-ment. Except for its epimer, two other isomers of mammillarinin were tentatively identified as betanidin/isobetanidin 5-O-(4'-O-malonyl)-beta-sophoroside present in the fruits as acyl migration products.

  7. Extra-Articular Lateral Tenodesis for Anterior Cruciate Ligament Deficient Knee: A Case Report

    PubMed Central

    García-Germán, Diego; Menéndez, Pablo; de la Cuadra, Pablo; Rodríguez-Arozena, Ricardo

    2013-01-01

    We present the case of an extra-articular lateral tenodesis for an anterior cruciate ligament (ACL) deficient knee. A 46-year-old male patient sustained an ACL graft rupture after a motorcycle accident. He complained of rotational instability and giving-way episodes. His previous graft was fixed by an intra-articular femoral staple that was not possible to remove at the time of the ACL revision. A modified Lemaire procedure was then performed. He gained rotational stability and was able to resume his sporting activities. We believe that isolated extra-articular reconstructions may still have a role in selected indications including moderate-demand patients complaining of rotational instability after ACL graft failure. PMID:24369517

  8. [Anterio-lateral extra-articular tenodesis of the knee using a short strip of fascia lata].

    PubMed

    Christel, P; Djian, P

    2002-09-01

    This study describes a lateral extra-articular tenodesis using a short strip of ilio-tibial band. The tenodesis consists of a 12 x 75 mm strip of iliotibial band remaining attached to the Gerdy's tubercle. An isometric point in the region of Krackow's point F-9 is determined with a callipers. The strip of iliotibial band is twisted by 180 degrees to enhance its isometry. Then it is either onlay with a screw and spiked washer on the F-9 point, or within a transverse tunnel drilled through the lateral femoral condyle, from the F-9 point, using and interference screw. Thus, the uses of a short ilio-tibial band tenodesis with a 180 degrees twist in combination with a BPTB reconstruction of the ACL, leads to similar results that the combined classic Lemaire tenodesis, with shorter skin incision, shorter graft harvesting, and at least on the biomechanical standpoint a better graft isometry.

  9. Potential assessed in Argentina's association contract areas

    SciTech Connect

    Pucci, J.C. , Buenos Aires )

    1994-06-20

    The majority of the Austral basin fields discovered are mainly associated with structural and combination traps. Except for El Condor, La Sara, and San Sebastian fields, most of the oil reserves of limited size. This is due to several factors: small areal extent (5--50 sq km), variability of the Springhill thickness which frequently wedges out over the top of structures, facies changes and related complex reservoir distributions, and lack of hydrocarbons. Until 1985, all the commercial discoveries have been made in the area of the platform mostly in the Springhill reservoir and to a lesser extent on top of the volcanic Bahia Laura group (equivalent Lemaire or Tobifera formations). However, the Tertiary discoveries in Campo Boleadoras and Puesto Peter fields opened a zone, named Intermediate'' by YPF's geologists, located to the west of the known producing areas. In this zone, the lower member of the Magallanes group has yielded production. Reservoir characteristics are discussed.

  10. Redetermination of Dy3Ni from single-crystal X-ray data

    PubMed Central

    Levytskyy, Volodymyr; Babizhetskyy, Volodymyr; Kotur, Bohdan; Smetana, Volodymyr

    2013-01-01

    The classification of the title compound, tridysprosium nickel, into the Fe3C (or Al3Ni) structure type has been deduced from powder X-ray diffraction data with lattice parameters reported in a previous study [Lemaire & Paccard (1967 ▶). Bull. Soc. Fr. Mineral. Cristallogr. 40, 311–315]. The current re-investigation of Dy3Ni based on single-crystal X-ray data revealed atomic positional parameters and anisotropic displacement parameters with high precision. The asymmetric unit consists of two Dy and one Ni atoms. One Dy atom has site symmetry .m. (Wyckoff position 4c) and is surrounded by twelve Dy and three Ni atoms. The other Dy atom (site symmetry 1, 8d) has eleven Dy and three Ni atoms as neighbours, forming a distorted Frank–Kasper polyhedron. The coordination polyhedron of the Ni atom (.m., 4c) is a tricapped trigonal prism formed by nine Dy atoms. PMID:24454015

  11. New Observation of the Polar Wind in the Topside Ionosphere

    NASA Astrophysics Data System (ADS)

    Yau, Andrew W.; Howarth, Andrew

    2016-07-01

    The theoretical prediction of the "classical" polar wind dates back to the works of Banks et al., Lemaire et al., Marubashi, Nishida, and other authors in the late sixties and early seventies. Since then, direct in-situ observations of the polar wind have been made on a number of satellites above the topside ionosphere, notably ISIS-2, Akebono, and DE-1, at altitudes of 1400-50,000 km. In this paper, we present the first in-situ observation of the polar wind inside the topside ionosphere on the Enhanced Polar Outflow Probe (e-POP) down to 600 km, and we compare our low-altitude observation with earlier observations at higher altitudes as well as theoretical predictions.

  12. Patients With Ligament Hiperlaxity With Rupture Of Previous Plastic For ACL. Reconstruction With Intra-articular And Extra-articular Combined Technics

    PubMed Central

    Astore, Ignacio; Agotegaray, Juan Ignacio; Comba, Ignacio; Bisiach, Luciana

    2017-01-01

    Introduction: In cases of patients with ligament hiperlaxity with rupture of ACL, the use of a BTB graft is recommended for its reconstruction. Our job consists of the clinical and functional assessment of a group of 10 patients with ligament laxaty according to Beighton scale, who, after surgery for ACL rupture with BTB technique, suffered a rupture of the plastic. For its reconstruction a combination of intra-articular and extra-articular techniques was used with a BTB graft in the contralateral knee, associated with a modified Lemaire technique. Methods: The series consists of 10 patients, male, average age of 24.2 years, amateur athletes, operated for a second time in March, 2011 and November, 2013, with a minimum follow-up of 24 months. They were evaluated before surgery and 24 months after surgery based on Lysholm scale, IKDC evaluation form and a physical exam (Lachman - Pivot Shift). Results: After surgery, the average in Lysholm scale was of 87.6 and 86.3 for the IKDC subjetive form. In the physical exam, 8 patients showed Lachman 1+, while none of the patients showed Pivot Shift positive. 7 patients were able to return to their usual sport activities. As a postoperative disadvantage, 6 patients reported pain in the external face of the knee in the first 6 months. And 4 patients reported a subjetive loss of full extension that did not interfere with their sport activities. Conclusion: Based on our experience and literature, we believe that the combination of both techniques, intra-articular (BTB) and extra-articular (Lemaire), is a good alternative for patients with ligament laxaty, providing positive clinical and functional results.

  13. Targets of an invasive species: oviposition preference and larval performance of Cactoblastis cactorum (Lepidoptera: Pyralidae) on 14 North American opuntioid cacti.

    PubMed

    Jezorek, Heather A; Stiling, Peter D; Carpenter, James E

    2010-12-01

    Cactoblastis cactorum Berg (Lepidoptera: Pyralidae), the cactus moth, is a well-known biological control agent of prickly pear cactus (Cactaceae: Opuntia Miller). The arrival of the moth in Florida and its subsequent spread through the southeastern United States poses a threat to opuntioid diversity in North America. Of particular concern are the ecological and economic impacts the moth could have in the southwestern United States and Mexico, where both native and cultivated Opuntia species are important resources. It is unknown which species would best support larval development if the moth were to spread further westward in North America. This study aimed to determine if ovipositing females demonstrate preferences for any of 14 common opuntioids native to or naturalized in Mexico and the southwestern United States; which of these opuntioids best support larval development; and if oviposition preference correlates with larval performance, as predicted by simple adaptive models. Results from a field experiment showed that female moths preferred O. engelmannii Salm-Dyck ex Engelmann variety linguiformis (Griffiths) Parfitt and Pinkava and O. engelmannii variety engelmannii for oviposition. A generalized linear model showed number of cladodes and degree of spininess to be significant predictors of oviposition activity. Results from a no-choice larval survival experiment showed Consolea rubescens (Salm-Dyck ex de Candolle.) Lemaire and O. streptacantha Lemaire to be the best hosts. Epidermal toughness was a significant predictor of most larval fitness parameters. In general, oviposition preference was not correlated with larval performance. A lack of co-evolutionary history between C. cactorum and North American opuntioid species may help explain this disconnect.

  14. Mathematical Model of Bone Remodeling Captures the Antiresorptive and Anabolic Actions of Various Therapies.

    PubMed

    Ross, David S; Mehta, Khamir; Cabal, Antonio

    2017-01-01

    A better understanding of the molecular pathways regulating the bone remodeling process should help in the development of new antiresorptive regulators and anabolic regulators, that is, regulators of bone resorption and of bone formation. Understanding the mechanisms by which parathyroid hormone (PTH) influences bone formation and how it switches from anabolic to catabolic action is important for treating osteoporosis (Poole and Reeve in Curr Opin Pharmacol 5:612-617, 2005). In this paper we describe a mathematical model of bone remodeling that incorporates, extends, and integrates several models of particular aspects of this biochemical system (Cabal et al. in J Bone Miner Res 28(8):1830-1836, 2013; Lemaire et al. in J Theor Biol 229:293-309, 2004; Peterson and Riggs in Bone 46:49-63, 2010; Raposo et al. in J Clin Endocrinol Metab 87(9):4330-4340, 2002; Ross et al. in J Disc Cont Dyn Sys Series B 17(6):2185-2200, 2012). We plan to use this model as a bone homeostasis platform to develop anabolic and antiresorptive compounds. The model will allow us to test hypotheses about the dynamics of compounds and to test the potential benefits of combination therapies. At the core of the model is the idealized account of osteoclast and osteoblast signaling given by Lemaire et al. (J Theor Biol 229:293-309, 2004). We have relaxed some of their assumptions about the roles of osteoprotegerin, transforming growth factor [Formula: see text], and receptor activator of nuclear factor [Formula: see text]B ligand; we have devised more detailed models of the interactions of these species. We have incorporated a model of the effect of calcium sensing receptor antagonists on remodeling (Cabal et al. in J Bone Miner Res 28(8):1830-1836, 2013). We have also incorporated a basic model of the effects of vitamin D on calcium homeostasis. We have included a simple model of the mechanism proposed by Bellido et al. (2003), Ross et al. (J Disc Cont Dyn Sys Series B 17(6):2185-2200, 2012), of the

  15. Connecting World Heritage Nominations and Monitoring with the Support of the Silk Roads Cultural Heritage Resource Information System

    NASA Astrophysics Data System (ADS)

    Vileikis, O.; Dumont, B.; Serruys, E.; Van Balen, K.; Tigny, V.; De Maeyer, P.

    2013-07-01

    Serial transnational World Heritage nominations are challenging the way cultural heritage has been managed and evaluated in the past. Serial transnational World Heritage nominations are unique in that they consist of multiple sites listed as one property, distributed in different countries, involving a large diversity of stakeholders in the process. As a result, there is a need for precise baseline information for monitoring, reporting and decision making. This type of nomination requires different methodologies and tools to improve the monitoring cycle from the beginning of the nomination towards the periodic reporting. The case study of the Silk Roads Cultural Heritage Resource Information System (CHRIS) illustrates the use of a Geographical Content Management System (Geo-CMS) supporting the serial transnational World Heritage nomination and the monitoring of the Silk Roads in the five Central Asian countries. The Silk Roads CHRIS is an initiative supported by UNESCO World Heritage Centre (WHC) and the Belgian Federal Science Policy Office (BELSPO), and developed by a consortium headed by the Raymond Lemaire International Centre for Conservation (RLICC) at the KULeuven. The Silk Roads CHRIS has been successfully assisting in the preparation of the nomination dossiers of the Republics of Kazakhstan, Tajikistan and Uzbekistan and will be used as a tool for monitoring tool in the Central Asian countries.

  16. Strong Quantum Coupling Between O-H+-O Stretch and Flanking Group Motions in (CH_3OH)_2H^+ Part i: Unmasking the 800-1200 wn Peaks

    NASA Astrophysics Data System (ADS)

    Tan, Jake Acedera; Kuo, Jer-Lai

    2016-06-01

    Assigning the vibrational signatures between 800-1200 wn is not a trivial task for (CH_3OH)_2H^+. Such complication in the assignment arises due to the intermode coupling between O-H+-O stretch and flanking group motions. In this talk, we will examine the interactions between O-H+-O stretch and four flanking group motions: 1) out-of-phase C-O stretch, 2) in-plane CH_3 rock, 3) out-of-plane CH_3, and 4) O-O stretch. Vibrational interactions were investigated by solving a reduced-dimensional Schrödinger equation by means of Discrete Variable Representation (DVR) with harmonic oscillators as basis. Potential and dipole moment surfaces were constructed by scanning along normal mode coordinates using MP2 and CCSD(T) level. It was found out that the O-H+-O stretch strongly couples with the four above mentioned flanking motions, leading to intensity redistribution on peaks between 800-1200 wn. J.R. Roscioli, L.R. McCunn and M.A. Johnson. Science 2007, 316, 249 T.D. Fridgen, L. Macaleese, T.B McMahon, J. Lemaire and P. Maitre. Phys. Chem. Chem. Phys. 2006, 8, 955-966 J.A. Tan and J.-L. Kuo. J. Phys. Chem. A. 2015, 119, 11320-11328

  17. Redetermination of dysprosium trinickel from single-crystal X-ray data.

    PubMed

    Levytskyy, Volodymyr; Babizhetskyy, Volodymyr; Kotur, Bohdan; Smetana, Volodymyr

    2012-11-01

    The crystal structure of the title compound, DyNi(3), was redetermined from single-crystal X-ray diffraction data. In comparison with previous studies based on powder X-ray diffraction data [Lemaire & Paccard (1969 ▶). Bull. Soc. Fr. Minéral. Cristallogr.92, 9-16; Tsai et al. (1974 ▶). J. Appl. Phys.45, 3582-3586], the present redetermination revealed refined coordinates and anisotropic displacement parameters for all atoms. The crystal structure of DyNi(3) adopts the PuNi(3) structure type and can be derived from the CaCu(5) structure type as an inter-growth structure. The asymmetric unit contains two Dy sites (site symmetries 3m and -3) and three Ni sites (m, 3m and -3m). The two different coordination polyhedra of Dy are a Frank-Kasper polyhedron formed by four Dy and 12 Ni atoms and a pseudo-Frank-Kasper polyhedron formed by two Dy and 18 Ni atoms. The three different coordination polyhedra of Ni are Frank-Kasper icosa-hedra formed by five Dy and seven Ni atoms, three Dy and nine Ni atoms, and six Dy and six Ni atoms.

  18. Refinement of the HeH2 potential surface through inversion of nuclear spin relaxation data

    NASA Astrophysics Data System (ADS)

    Lazarides, A. A.; Rabitz, H.

    1997-05-01

    Proton spin relaxation times, T1/ρ (the slope of the longitudinal relaxation time, T1, vs density, ρ) in the infinite dilution limit as measured by Lemaire and Armstrong [J. Chem. Phys. 81, 5275 (1984)] at temperatures between 86 and 298 K are used to refine the anisotropic term of the Rodwell-Scoles HeH2 potential [J. Phys. Chem. 86, 1053 (1982)]. Prior to the refinement, a sensitivity study is performed which indicates that the data are primarily sensitive to the relative anisotropy of the repulsive wall. The inversion problem is posed as a first-order Fredholm integral equation with a kernel composed of functional sensitivities that relate potential perturbations to spin relaxation rate perturbations. The inversion scheme consists of a least-squares regularization procedure with singular system analysis and stabilization as used previously to refine atom-atom potentials [T.-S. Ho and H. Rabitz, J. Chem. Phys. 89, 5614 (1988); 90, 1519 (1989); 91, 7590 (1989)] with modifications which incorporate a priori information about the quality of the experimental data and the starting potential. The inversion yields a refined anisotropic term which in the repulsive region increases the anisotropic radial function V2(R) by approximately 10% and eliminates more than 80% of the discrepancy between the values of T1/ρ predicted by the potential and the values determined by experiment. The relative anisotropy, V2/V0, of the refined repulsive wall closely matches that of two potentials recently derived from ab initio calculation.

  19. Laboratory and Numerical Simulations of the Impulsive Penetration Mechanism

    NASA Astrophysics Data System (ADS)

    Echim, M. M.; Lemaire, J. F.

    2000-05-01

    Plasma interaction at the interface between the magnetosheath and magnetosphere has been extensively studied during recent years. As a consequence various theoretical models have emerged. The impulsive penetration mechanism initially proposed by Lemaire and Roth as an alternative approach to the steady state reconnection, is a non-stationary model describing the processes which take place when a 3-D solar wind plasma irregularity interacts with the outer regions of the Earth's magnetosphere. In this paper we are reviewing the main features of the impulsive penetration mechanism and the role of the electric field in driving impulsive events. An alternative point of view and the controversy it has raised are discussed. We also review the numerical codes developed to simulate the impulsive transport of plasma across the magnetopause. They have illustrated the relationship between the magnetic field distribution and the convection of solar-wind plasma inside the magnetosphere and brought into perspective non-stationary phenomena (like instabilities and waves) which were not explicitly integrated in the early models of impulsive penetration. Numerical simulations devoted to these processes cover a broad range of approximations, from ideal MHD to hybrid and kinetic codes. The results show the limitation of these theories in describing the full range of phenomena observed at the magnetopause and magnetospheric boundary layers.

  20. Extra-articular tenodesis for anterior cruciate ligament rupture in amateur skiers.

    PubMed Central

    Neyret, P; Palomo, J R; Donell, S T; Dejour, H

    1994-01-01

    Thirty one amateur skiers with 33 knees which had had a symptomatic chronic rupture of the anterior cruciate ligament (ACL) treated with the Lemaire operation were reviewed retrospectively at an average of 4.5 years. Of the patients 23 were women. The operation failed to control symptoms in 17 out of the 33 knees. However the operation did control symptoms in 13 out of 19 knees in patients over 35 years old, compared with only three out of 14 knees in patients under 35 years old. Clinical and objective testing however showed that most knees were still unstable. Despite this 21 patients continued skiing. One patient with a successful result switched to playing tennis. Five patients gave up all sports. Four further patients, all under 35 years old, returned to skiing after an additional intra-articular reconstruction of the anterior cruciate ligament. An isolated extra-articular procedure in amateur skiers under 35 years old with symptomatic chronic ACL rupture is not recommended. They need at least an intra-articular reconstruction to control their symptoms and to stabilize the knee. PMID:8044490

  1. Expertise in ill-defined problem-solving domains as effective strategy use.

    PubMed

    Schunn, Christian D; McGregor, Mark U; Saner, Lelyn D

    2005-12-01

    Expertise consists of many different cognitive structures. Lemaire and Siegler (1995) have proposed a four-layered account of expertise from a strategies perspective: Experts have better strategies, tend to use strategies that are better overall more often, are better able to select the circumstances to which a strategy best applies, and are better able to execute a given strategy. Originally, this account came from work in simple, well-defined domains. We explored this account in the complex, ill-defined domain of platoon leadership. In Experiment 1A, we elicited free-text responses to leadership scenarios from novices, intermediates, and experts, finding expertise effects for strategy base rates and choice, but not for strategy existence or the number of strategies used. In Experiment 1B, we used a new group of experts to gather ratings of the execution accuracy of the responses in Experiment 1A and found expertise differences in the ability to execute the same strategies. We propose several elaborations to the original four-layered strategies account of expertise on the basis of these results.

  2. Coleopterans Associated with Plants that form Phytotelmata in Subtropical and Temperate Argentina, South America

    PubMed Central

    Campos, Raúl E.; Fernández, Liliana A.

    2011-01-01

    A list of the most common plants that form phytotelmata and their associated coleopterans (aquatic, semi-aquatic and terrestrial) from the northeastern subtropical and temperate area of Argentina, South America with biological and behavioral observations is presented in this study. Species of Poaceae (n = 3), Bromeliaceae (5), Apiaceae (6), Araceae (2), Urticaceae (1), Marantaceae (1), Arecaceae (1), Dipsacaceae (1) and Cyperaceae (1) were identified as phytotelmata. Aquatic species of Scirtidae (2), Dytiscidae (2), and Hydrophilidae (4), semi-aquatic Chelonariidae (2), and terrestrial species of Carabidae (3), Staphylinidae (5), Histeridae (1), Elateridae (1), Cantharidae (1), Cleridae (1), Tenebrionidae (1), Meloidae (1), Anthicidae (1), Chrysomelidae (3), Curculionidae (7) and Apionidae (1) were identified from six species of Eryngium L. (Apiales: Apiaceae), two species of Guadua Kunth (Poales: Poaceae), Aechmea distichantha Lemaire (Poales: Bromeliaceae), and from fallen leaves of Euterpe edulis Martius (Arecales: Arecaceae) from the temperate and subtropical area. The highest species richness was recorded in Eryngium phytotelmata. Fifteen species of beetles inhabit Eryngium cabrerae Pontiroli, 11 in E. horridum Malme, 7 in E. stenophyllum Urban, 4 in E. aff. serra Chamisso and Schlechtendal., 3 in E. elegans Chamisso and Schlechtendal, 2 in E. eburneum Decne and E. pandanifolium Chamisso and Schlechtendal. From bamboo, 6 species of coleopterans were collected from Guadua trinii (Nees) Nees ex Ruprecht and 4 from G. chacoensis (Rojas) Londoño and Peterson. Three species of aquatic coleopterans were recorded from A. distichantha and only one from E. edulis. PMID:22236084

  3. Strong Quantum Coupling Between O-H+-O Stretch and Flanking Group Motions in (CH_3OH)_2H^+ Part II: Tuning the Coupling via Isotopologues

    NASA Astrophysics Data System (ADS)

    Tan, Jake Acedera; Kuo, Jer-Lai

    2016-06-01

    The vibrational coupling between O-H+-O/O-D+-O stretch and flanking group motions were explored in the following isotopologues: (CH_3OH)_2H^+, (CD_3OH)_2H^+, (CH_3OD)_2D^+, and (CD_3OD)_2D^+. At present only measurements for (CH_3OH)_2H^+ are available in the literature. Reduced-dimensional calculations were performed by solving several vibrational Schrödinger equations using the method of Discrete Variable Representation (DVR) with harmonic oscillator as basis. Both potential and dipole moment surfaces were constructed at MP2/aug-cc-pVDZ by scanning along normal modes corresponding to: 1) O-H+-O/O-D+-O stretch, 2) out-of-phase C-O stretch, 3) in-plane CH_3/CD_3 rock, 4) out-of-plane CH_3/CD_3 rock, and 5) O-O stretch. It was found that vibrational states for isotopologues corresponding to O-H+-O are more mixed than that of the O-D+-O. Lastly, we proposed tentative assignments for the simulated spectrum and hope that experimental measurements will be available in the near future. J.R. Roscioli, L.R. McCunn and M.A. Johnson. Science 2007, 316, 249 T.D. Fridgen, L. Macaleese, T.B McMahon, J. Lemaire and P. Maitre. Phys. Chem. Chem. Phys. 2006, 8, 955-966

  4. Cytophotometric and biochemical analyses of DNA in pentaploid and diploid Agave species.

    PubMed

    Cavallini, A; Natali, L; Cionini, G; Castorena-Sanchez, I

    1996-04-01

    Nuclear DNA content, chromatin structure, and DNA composition were investigated in four Agave species: two diploid, Agave tequilana Weber and Agave angustifolia Haworth var. marginata Hort., and two pentaploid, Agave fourcroydes Lemaire and Agave sisalana Perrine. It was determined that the genome size of pentaploid species is nearly 2.5 times that of diploid ones. Cytophotometric analyses of chromatin structure were performed following Feulgen or DAPI staining to determine optical density profiles of interphase nuclei. Pentaploid species showed higher frequencies of condensed chromatin (heterochromatin) than diploid species. On the other hand, a lower frequency of A-T rich (DAPI stained) heterochromatin was found in pentaploid species than in diploid ones, indicating that heterochromatin in pentaploid species is made up of sequences with base compositions different from those of diploid species. Since thermal denaturation profiles of extracted DNA showed minor variations in the base composition of the genomes of the four species, it is supposed that, in pentaploid species, the large heterochromatin content is not due to an overrepresentation of G-C repetitive sequences but rather to the condensation of nonrepetitive sequences, such as, for example, redundant gene copies switched off in the polyploid complement. It is suggested that speciation in the genus Agave occurs through point mutations and minor DNA rearrangements, as is also indicated by the relative stability of the karyotype of this genus. Key words : Agave, DNA cytophotometry, DNA melting profiles, chromatin structure, genome size.

  5. Raman Spectroscopy of Serpentine and Reaction Products at High Pressure Using a Diamond Anvil Cell

    NASA Astrophysics Data System (ADS)

    Burgess, K.; Zinin, P.; Odake, S.; Fryer, P.; Hellebrand, E.

    2012-12-01

    Serpentine is one of the most abundant hydrous phases in the altered subducting plate, and contributes a large portion of the water flux in subduction zones. Measuring and understanding the structural changes in serpentine with pressure aids our understanding of the processes ongoing in oceanic crust and subduction zones. We have conducted high-pressure/high-temperature experiments on serpentine and its dehydration reaction products using a diamond anvil cell. We used the multifunctional in-situ measurement system equipped with a Raman device and laser heating system at the University of Hawaii. Well-characterized natural serpentinite was used in the study. Pressure was determined using the shift of the fluorescence line of a ruby placed next to the sample. Raman spectra of serpentine were obtained at higher pressures than previously published, up to 15 GPa; the peak shift with pressure fits the model determined by Auzende et al. [2004] at lower pressures. Heating was done at several different pressures up to 20 GPa, and reaction products were identified using Raman. Micro-Raman techniques allow us to determine reaction progress and heterogeneity within natural samples containing olivine and serpentine. Auzende, A-L., I. Daniel, B. Reynard, C. Lemaire, F. Guyot (2004). High-pressure behavior of serpentine minerals: a Raman spectroscopic study. Phys. Chem. Minerals 31 269-277.

  6. Identification of seven Zingiberaceous species based on comparative anatomy of microscopic characteristics of seeds

    PubMed Central

    2014-01-01

    Background The fruits and seeds of Alpinia galanga (L.) Willd., Alpinia katsumadai Hayata, Alpinia zerumbet (Pers.) Burtt. & Smith, Amomum kravanh Pierre ex Gagnep., Amomum subulatum Roxb., Amomum tsao-ko Crevost et Lemaire, and Elettaria cardamomum (L.) Maton from Alpinia, Amomum, and Elettaria genera in the Zingiberaceae family are difficult to distinguish between each other. This study aims to identify the seeds of these seven species from Zingiberaceae family based on comparative anatomy of microscopic characteristics. Methods We compared the morphological structures of seed coats by observing the microscopic characteristics of seeds in transverse sections. We described the macroscopic characteristics of seeds in detail. Results The seeds of these three genera could not be identified to the species level based on their macroscopic features. However, based on the anatomical features of the seed coat observed in transverse sections, a dichotomous key for these seven species was feasible. Conclusion Seven species in the Zingiberaceae family could be identified based on comparative anatomy of microscopic characteristics of transverse section of seed. PMID:24607026

  7. Coleopterans associated with plants that form phytotelmata in subtropical and temperate Argentina, South America.

    PubMed

    Campos, Raúl E; Fernández, Liliana A

    2011-01-01

    A list of the most common plants that form phytotelmata and their associated coleopterans (aquatic, semi-aquatic and terrestrial) from the northeastern subtropical and temperate area of Argentina, South America with biological and behavioral observations is presented in this study. Species of Poaceae (n = 3), Bromeliaceae (5), Apiaceae (6), Araceae (2), Urticaceae (1), Marantaceae (1), Arecaceae (1), Dipsacaceae (1) and Cyperaceae (1) were identified as phytotelmata. Aquatic species of Scirtidae (2), Dytiscidae (2), and Hydrophilidae (4), semi-aquatic Chelonariidae (2), and terrestrial species of Carabidae (3), Staphylinidae (5), Histeridae (1), Elateridae (1), Cantharidae (1), Cleridae (1), Tenebrionidae (1), Meloidae (1), Anthicidae (1), Chrysomelidae (3), Curculionidae (7) and Apionidae (1) were identified from six species of Eryngium L. (Apiales: Apiaceae), two species of Guadua Kunth (Poales: Poaceae), Aechmea distichantha Lemaire (Poales: Bromeliaceae), and from fallen leaves of Euterpe edulis Martius (Arecales: Arecaceae) from the temperate and subtropical area. The highest species richness was recorded in Eryngium phytotelmata. Fifteen species of beetles inhabit Eryngium cabrerae Pontiroli, 11 in E. horridum Malme, 7 in E. stenophyllum Urban, 4 in E. aff. serra Chamisso and Schlechtendal., 3 in E. elegans Chamisso and Schlechtendal, 2 in E. eburneum Decne and E. pandanifolium Chamisso and Schlechtendal. From bamboo, 6 species of coleopterans were collected from Guadua trinii (Nees) Nees ex Ruprecht and 4 from G. chacoensis (Rojas) Londoño and Peterson. Three species of aquatic coleopterans were recorded from A. distichantha and only one from E. edulis.

  8. Adiabatic Betatron deceleration of ionospheric charged particles: a new explanation for (i) the rapid outflow of ionospheric O ions, and for (ii) the increase of plasma mass density observed in magnetospheric flux tubes during main phases of geomagnetic s

    NASA Astrophysics Data System (ADS)

    Lemaire, Joseph; Pierrard, Viviane; Darrouzet, Fabien

    2013-04-01

    Using European arrays of magnetometers and the cross-phase analysis to determine magnetic field line resonance frequencies, it has been found by Kale et al. (2009) that the plasma mass density within plasmaspheric flux tubes increased rapidly after the SSC of the Hallowe'en 2003 geomagnetic storms. These observations tend to confirm other independent experimental results, suggesting that heavy ion up-flow from the ionosphere is responsible for the observed plasma density increases during main phases of geomagnetic storms. The aim of our contribution is to point out that, during main phases, reversible Betatron effect induced by the increase of the southward Dst-magnetic field component (|Δ Bz|), diminishes slightly the perpendicular kinetic energy (W?) of charged particles spiraling along field lines. Furthermore, due to the conservation of the first adiabatic invariant (μ = Wm/ Bm) the mirror points of all ionospheric ions and electrons are lifted up to higher altitudes i.e. where the mirror point magnetic field (Bm) is slightly smaller. Note that the change of the mirror point altitude is given by: Δ hm = -1/3 (RE + hm) Δ Bm / Bm. It is independent of the ion species and it does not depend of their kinetic energy. The change of kinetic energy is determined by: Δ Wm = Wm Δ Bm / Bm. Both of these equations have been verified numerically by Lemaire et al. (2005; doi: 10.1016/S0273-1177(03)00099-1) using trajectory calculations in a simple time-dependant B-field model: i.e. the Earth's magnetic dipole, plus an increasing southward B-field component: i.e. the Dst magnetic field whose intensity becomes more and more negative during the main phase of magnetic storms. They showed that a variation of Bz (or Dst) by more than - 50 nT significantly increases the mirror point altitudes by more than 100 km which is about equal to scale height of the plasma density in the topside ionosphere where particles are almost collisionless (see Fig. 2 in Lemaire et al., 2005

  9. Experimental acquisition, development, and transmission of Leishmania tropica by Phlebotomus duboscqi.

    PubMed

    Hanafi, Hanafi A; El-Din, El-Shaimaa M Nour; El-Hossary, Shabaan S I; Kaldas, Rania M; Villinski, Jeffrey T; Furman, Barry D; Fryauff, David J

    2013-01-01

    We report experimental infection and transmission of Leishmania tropica (Wright), by the blood-feeding sand fly Phlebotomus duboscqi (Neveu-Lemaire). Groups of laboratory-reared female sand flies that fed "naturally" on L. tropica-infected hamsters, or artificially, via membrane feeding device, on a suspension of L. tropica amastigotes, were dissected at progressive time points post-feeding. Acquisition, retention and development of L. tropica through procyclic, nectomonad, and leptomonad stages to the infective metacyclic promastigote stage, and anterior progression of the parasites from abdominal midgut bloodmeal to the thoracic midgut were demonstrated in both groups. Membrane feeding on the concentrated amastigote suspension led to metacyclic promastigote infections in 60% of sand flies, whereas only 3% of P. duboscqi that fed naturally on an infected hamster developed metacyclics. Sand flies from both groups re-fed on naïve hamsters, but despite infections in 25-50% of membrane-fed and 2-3.5% of naturally fed flies, no skin lesions developed in the hamsters. After four months of observation these animals were euthanized and necropsied. Screening of the organs and tissue by polymerase chain reaction (PCR) that targeted the small subunit RNA gene, amplified generic Leishmania DNA from liver, spleen, bone marrow, and blood, but only from hamsters bitten by membrane-infected P. duboscqi. These results are notable in demonstrating the ability of P. duboscqi, originating from Kenya, to acquire, retain, develop, and transmit a Turkish strain of L. tropica originally isolated from a human case of cutaneous leishmaniasis. This marks the first demonstration of complete development and transmission of L. tropica by a member of the Phlebotomus subgenus of sand flies.

  10. Biomechanical Results of Lateral Extra-articular Tenodesis Procedures of the Knee: A Systematic Review.

    PubMed

    Slette, Erik L; Mikula, Jacob D; Schon, Jason M; Marchetti, Daniel C; Kheir, Matthew M; Turnbull, Travis Lee; LaPrade, Robert F

    2016-12-01

    To systematically review and compare biomechanical results of lateral extra-articular tenodesis (LET) procedures. A systematic review was performed using the PubMed, Medline, Embase, and Cochrane databases. The search terms included the following: extraarticular, anterolateral, iliotibial, tenodesis, plasty, augmentation, procedure, reconstruction, technique, biomechanics, kinematic, robot, cadaver, knee, lateral tenodesis, ACL, Marcacci, Lemaire, Losee, Macintosh, Ellison, Andrews, Hughston, and Muller. The inclusion criteria were nonanatomic, in vitro biomechanical studies, defined as in vitro investigations of joint motion resulting from controlled, applied forces. Of the 10 included studies, 7 analyzed anterior tibial translation and reported that isolated LET procedures did not restore normal anterior stability to the anterior cruciate ligament (ACL)-deficient knee. Seven of the 8 studies analyzing tibial rotation reported a reduction in internal tibial rotation across various flexion angles in the ACL-deficient knee when compared with the native state. Five studies reported a reduction in intra-articular graft force with the addition of an LET. Two studies evaluated length change patterns, graft course, and total strain range and found that reconstruction techniques in which the graft attached proximal to the lateral epicondyle and coursed deep to the fibular collateral ligament were most isometric. In the ACL-deficient knee, LET procedures overconstrained the knee and restricted internal tibial rotation when compared with the native state. In addition, isolated LET procedures did not return normal anterior stability to the ACL-deficient knee but did significantly reduce anterior tibial translation and intra-articular graft forces during anteriorly directed loading. Combined injury to the ACL and anterolateral structures has been reported to exhibit greater anterolateral rotatory instability when compared with isolated ACL injuries. Despite the reported

  11. The relationships of marsupial-dwelling Viannaiidae and description of Travassostrongylus scheibelorum sp. n. (Trichostrongylina: Heligmosomoidea) from mouse opossums (Didelphidae) from French Guiana.

    PubMed

    Scheibel, R Philip; Catzeflis, François; Jiméñez, F Agustín

    2014-06-01

    The trichostrongylid nematode Travassostrongylus scheibelorum sp. n. from the Linnaeus' mouse opossum, Marmosa murina (Linnaeus) (type host), and the woolly mouse opossum, Marmosa demerarae (Thomas), from French Guiana is described. The nematodes have a synlophe with ridges frontally oriented from right to left, six dorsal and six ventral, at midbody; seven dorsal and seven ventral posterior to the vulva, and two cuticular thickenings within the lateral spaces; a long dorsal ray and a pointed cuticular flap covering the vulva. This is the 12th species of Travassostrongylus Orloff, 1933, which includes species featuring ridges around the synlophe and a didelphic condition. These traits contrast with those in other genera in the Viannaiidae Neveu-Lemaire, 1934, which feature ventral ridges on the synlophe of adults and a monodelphic condition. Members of the family are chiefly Neotropical and are diagnosed based on the presence of a bursa of the type 2-2-1, 2-1-2 or irregular, and cuticle without ridges on the dorsal side (at least during one stage of their development). Herein, we present a reconstruction of the ancestral states of the didelphic/monodelphic condition and the cuticular ridges that form the synlophe in opossum-dwelling trichostrongyles, namely Travassostrongylus and Viannaia Travassos, 1914. Our investigations suggest they are not reciprocal sister taxa and that the change from didelphy to monodelphy and the loss of dorsal ridges, occurred in the common ancestor of species of Viannaia. These results suggest a synlophe with three ventral ridges is not plesiomorphic in the opossum dwelling trichostrongylids.

  12. Biology and Host Range of Digitivalva delaireae (Lepidoptera: Glyphipterigidae), a Candidate Agent for Biological Control of Cape-ivy (Delairea odorata) in California and Oregon.

    PubMed

    Mehelis, Christopher N; Balciunas, Joe K; Reddy, Angelica M; Van Der Westhuizen, Liame; Neser, Stefan; Moran, Patrick J

    2015-04-01

    Cape-ivy (Delairea odorata Lemaire) is an ornamental vine native to South Africa that has escaped into natural areas in coastal California and Oregon, displacing native vegetation. Surveys in South Africa led to the discovery of the leaf- and stem-mining moth Digitivalva delaireae Gaedike and Kruger (Lepidoptera: Glyphipterigidae: Acrolepiinae) as one of several common and damaging native herbivores on Cape-ivy. In greenhouse studies, adult female life span averaged 16 d (46 d maximum). Most (72%) mated females began laying eggs within 72 h of emergence. Females had an average lifetime fecundity of 52 eggs, with >70% laid on leaf laminae, and 89% of eggs were laid by the 15th day postemergence. Lifetime fertility (adult production) averaged three to four offspring per female. At 25 °C, egg hatch required 10 d, pupal formation 26 d, and adult emergence 41 d, while under variable greenhouse and laboratory conditions development to adult required 54-60 d. In four-way choice tests, involving 100 plant species other than Cape-ivy, including 11 genera and 37 species in the Asteraceae, subtribe Senecioninae from both native and invaded ranges, D. delaireae inflicted damage and produced pupae only on Cape-ivy. Leaf mining damage occurred on 30% of leaves of native Senecio hydrophilus in no-choice tests and on 2% of leaves in dual-choice tests, but no pupation occurred. If approved for field release in the continental United States, the moth D. delaireae is expected to produce multiple generations per year on Cape-ivy, and to pose little risk of damage to native plants. Published by Oxford University Press on behalf of Entomological Society of America 2015. This work is written by US Government employees and is in the public domain in the US.

  13. Water relations and photosynthesis of a barrel cactus, Ferocactus acanthodes, in the Colorado desert.

    PubMed

    Nobel, Park S

    1977-06-01

    The structural characteristics, water relations, and photosynthesis of Ferocactus acanthodes (Lemaire) Britton and Rose, a barrel cactus exhibiting Crassulacean acid metabolism (CAM), were examined in its native habitat in the western Colorado desert. Water storage in its succulent stem permitted nighttime stomatal opening ot continue for about 40 days after the soil water potential became less than that of the stem, a period whe the plant would be unable to extract water from the soil. After 7 months of drought and consequent unreplenished water loss from a plant, diurnal stomatal activity was not observed and the stem osmotic pressure was 6.4 bars, more than double the value measured during wet periods with nighttime stomatal opening. F. acanthodes had a shallow root system (mean depth of 8 cm) which responded within 24 h to rainfall.When the nocturnal stem surface temperature was raised from 8.0° C to 35.0° C, the stomatal resistance increased 4-fold, indicating that cool nighttime temperatures are advantageous for gas exchange by F. acanthodes. Moreover, the optimal temperature for CO2 uptake in the dark was only 12.6° C. CO2 uptake at night became maximal for 3.0 mEinsteins cm(-2) of photosynthetically active radiation incident during the preceding day, and the minimum number of incident quanta absorbed per CO2 fixed was 68. The transpiration ratio (mass of water transpired/mass of CO2 fixed) had the relatively low value of 70 for an entire year, consistent with values obtained for other CAM plants. The total amount of water annually diverted to the floral structures was about 6% of the stem wet weight. The annual growth increment estimated from the net CO2 assimilation corresponded to about 10% of the stem mass for barrel cacti 34 cm tall, in agreement with measured dimension changes, and indicated that such plants were about 26 years old.

  14. Model structure and control of bone remodeling: a theoretical study.

    PubMed

    Pivonka, Peter; Zimak, Jan; Smith, David W; Gardiner, Bruce S; Dunstan, Colin R; Sims, Natalie A; Martin, T John; Mundy, Gregory R

    2008-08-01

    It is generally accepted that RANKL is highly expressed in osteoblast precursor cells while OPG is highly expressed in mature osteoblasts, but to date no functional utility to the BMU has been proposed for this particular ligand-decoy-receptor expression profile. As discovered in the mid 90s, the RANK-RANKL-OPG signaling cascade is a major signaling pathway regulating bone remodeling. In this paper we study theoretically the functional implications of particular RANKL/OPG expression profiles on bone volume. For this purpose we formulate an extended bone-cell dynamics model describing functional behaviour of basic multicellular units (BMUs) responsible for bone resorption and formation. This model incorporates the RANK-RANKL-OPG signaling together with the regulating action of TGF-beta on bone cells. The bone-cell population model employed here builds on the work of Lemaire et al. (2004) [1], but incorporates the following significant modifications: (i) addition of a rate equation describing changes in bone volume with time as the key 'output function' tracking functional behaviour of BMUs, (ii) a rate equation describing release of TGF-beta from the bone matrix, (iii) expression of OPG and RANKL on both osteoblastic cell lines, and (iv) modified activator/repressor functions. Using bone volume as a functional selection criterion, we find that there is a preferred arrangement for ligand expression on particular cell types, and further, that this arrangement coincides with biological observations. We then investigate the model parameter space combinatorially, searching for preferred 'groupings' of changes in differentiation rates of various cell types. Again, a criterion of bone volume change is employed to identify possible ways of optimally controlling BMU responses. While some combinations of changes in differentiation rates are clearly unrealistic, other combinations of changes in differentiation rates are potentially functionally significant. Most importantly

  15. Interpretation of recent AMPTE data at the magnetopause

    NASA Astrophysics Data System (ADS)

    Heikkila, Walter J.

    1997-02-01

    Phan and Paschmann [1996] have done a superposed epoch analysis of conditions near the dayside magnetopause and have found significant structure within the magnetopause current sheet itself. Among their many important results is that the electron temperature for an outward profile shows cooling of the solar wind plasma for the inner part followed by heating for the outer. Since these two cases are associated with E-J<0 and E.J>0, this pivotal result can be interpreted as evidence for a dynamo-load combination. This was hypothesized by Heikkila [1982a] for the localized impulsive penetration of solar wind plasma through the magnetopause current sheet; the process involves an inductive electric field Eind given by Lenz's law around the current perturbation (the electromotive force) and a plasma response through charge separation caused by Eind, a process which is controlled by the normal component of the magnetic field Bn at the magnetopause. A dynamo is not included in the standard definition of reconnection, only the reconnection load. Another key result is a remarkable difference between inbound and outbound crossings of the normal component of plasma velocity vn. This can be understood on the basis of two complementary processes involving (1) a polarization electric field which does not depend on the movement of the magnetopause itself [Lemaire and Roth, 1978] and (2) the inductive electric field due to magnetopause erosion which does. These results have opened a new chapter on solar wind-magnetospheric interaction. They demonstrate that the concepts of frozen-in flow and of magnetic reconnection (as defined) are inappropriate at the magnetopause. Rather, the interaction of the solar wind plasma at the magnetopause depends on a localized pressure pulse whose effects vary greatly on the magnetic field topology, i.e., whether the magnetopause is a tangential or rotational discontinuity

  16. Protecting Unesco World Heritage PROPERTIES'S Integrity: the Role of Recording and Documentation in Risk Management for PETRA

    NASA Astrophysics Data System (ADS)

    Santana Quintero, M.; Cesaro, G.; Ishakat, F.; Vandesande, A.; Vileikis, O.; Vadafari, A.; Paolini, A.; Van Balen, K.; Fakhoury, L.

    2012-07-01

    Risk management - as it has been defined - involves the decision-making process following a risk assessment (Ball, Watt, 2003). It is the process that involves managing to minimize losses and impacts on the significant of historic structures and to reach the balance between gaining and losing opportunities. This contribution explains the "heritage information" platform developed using low-cost recording, documentation and information management tools to serve as container for assessments resulting from the application of a risk methodology at a pilot area of the Petra Archaeological Park, in particular those that permit digitally and cost effective to prepare an adequate baseline record to identify disturbances and threats. Furthermore, this paper will reflect on the issue of mapping the World Heritage property's boundaries by illustrating a methodology developed during the project and further research to overcome the lack of boundaries and buffer zone for the protection of the Petra World Heritage site, as identified in this project. This paper is based on on-going field project from a multidisciplinary team of experts from the Raymond Lemaire International Centre for Conservation (University of Leuven), UNESCO Amman, Petra Development Tourism and Region Authority (PDTRA), and Jordan's Department of Antiquities (DoA), as well as, experts from Jordan. The recording and documentation approach included in this contribution is part of an on-going effort to develop a methodology for mitigating (active and preventive) risks on the Petra Archaeological Park (Jordan). The risk assessment has been performed using non-intrusive techniques, which involve simple global navigation satellite system (GNSS), photography, and structured visual inspection, as well as, a heritage information framework based on Geographic Information Systems. The approach takes into consideration the comparison of vulnerability to sites with the value assessment to prioritize monuments at risk based

  17. The anti-cancer drug 5-fluorouracil is metabolized by the isolated perfused rat liver and in rats into highly toxic fluoroacetate.

    PubMed Central

    Arellano, M.; Malet-Martino, M.; Martino, R.; Gires, P.

    1998-01-01

    We report the first demonstration of the biotransformation of the anti-cancer drug 5-fluorouracil (FU) into two new metabolites, alpha-fluoro-beta-hydroxypropionic acid (FHPA) and fluoroacetate (FAC), in the isolated perfused rat liver (IPRL) and in the rat in vivo. IPRL was perfused with solutions of pure FU at two doses, 15 or 45 mg kg(-1) body weight, and rats were injected i.p. with 180 mg of FU kg(-1) body weight. Fluorine-19 NMR analysis of perfusates from IPRL and rat urine showed the presence of the normal metabolites of FU and low amounts of FHPA (0.4% or 0.1% of injected FU in perfusates from IPRL treated with 15 or 45 mg of FU kg(-1) body weight, respectively; 0.08% of the injected FU in rat urine) and FAC (0.1% or 0.03% of injected FU in perfusates from IPRL treated with 15 or 45 mg of FU kg(-1) body weight, respectively; 0.003% of the injected FU in rat urine). IPRL was also perfused with a solution of alpha-fluoro-beta-alanine (FBAL) hydrochloride at 16.6 mg kg(-1) body weight dose equivalent to 15 mg of FU kg(-1) body weight. Low amounts of FHPA (0.2% of injected FBAL) and FAC (0.07%) were detected in perfusates, thus demonstrating that FHPA and FAC arise from FBAL catabolism. As FAC is a well-known cardiotoxic poison, and FHPA is also cardiotoxic at high doses, the cardiotoxicity of FU might stem from at least two sources. The first one, established in previous papers (Lemaire et al, 1992, 1994), is the presence in commercial solutions of FU of degradation products of FU that are metabolized into FHPA and FAC; these are formed over time in the basic medium necessary to dissolve the drug. The second, demonstrated in the present study, is the metabolism of FU itself into the same compounds. PMID:9459149

  18. Data Processing and In -flight Calibration/validation of Envisat and Jason Radiometers

    NASA Astrophysics Data System (ADS)

    Obligis, E.; Eymard, L.; Zanife, O. Z.

    Retrieval algorithms for wet tropospheric correction, integrated vapor and liquid water contents are formulated using a database of geophysical parameters from global analyses from a meteorological model and corresponding simulated brightness temperatures and backscattering cross -sections. Meteorological data are 12 hours predictions of the European Center for Medium range Weather Forecasts (ECMWF) model. Relationships between satellite measurements and geophysical parameters are formulated using a statistical method. Quality of retrieval algorithms depends therefore on the representativity of the database, the accuracy of the radiative transfer model used for the simulations and finally on the quality of the inversion model. The database has been built using the latest version of the ECMWF forecast model, which has been operationally run since November, 2000. The 60 levels in the model allows a complete description of the troposphere/s tratosphere profiles and the horizontal resolution is now half of a degree. The radiative transfer model is the emissivity model developed at the Université Catholique de Louvain [Lemaire, 1998], coupled to an atmospheric model [Liebe et al, 1993] for gazeous absorption. For the inversion, we will compare performances of a classical loglinear regression with those of a neural networks inversion. In case of Envisat, the backscattering coefficient in Ku band is used in the different algorithms to take into account the surface roughness like it is done with the 18 GHz channel for TOPEX algorithms and a third term in wind speed for ERS2 algorithms. The in-flight calibration/validation of both radiometers will consist first in the evaluation of the calibration by comparison of measurements with simulations, using the same radiative transfer model and several other ECMWF global meteorological fields at coincident locations with satellite measurements. Although such a method only provides the relative discrepancy with respect to the

  19. Review on hydroxylamine, a precursor to amino-acids

    NASA Astrophysics Data System (ADS)

    Lemaire, Jean Louis

    2015-08-01

    Does life on earth come from interstellar space (IS)?It has been recently demonstrated that part of the terrestrial water is of IS origin [Cleeves et al. Science 2014]. This raises the question whether materials like amino-acids or their pre-biotic molecular precursors could have been formed and brought to earth in the same way than water. Another question is whether these molecules were formed in the gas phase or through reactions on the surface/volume of ice-covered grains. This may then have occurred in the vicinity of proto-stellar cores or deep into a pristine dense molecular clouds at very low temperatures.As far as bio-related molecules are concerned, chemistry with nitrogen-bearing molecules (like NH3 and NO) is involved. I review recent experimental work showing that hydroxylamine (NH2OH) could be formed either by surface or by volume reactions in conditions close to those prevailing in dense media. They use either electron-UV irradiation of water-ammonia ices [Zheng & Kaiser JCPA 2010] or successive hydrogenation of solid nitric oxide[Congiu, Fedoseev & al. ApJL.2012] or the simple oxidation of ammonia [He, Vidali, Lemaire & Garrod, ApJ, 2015] or the reaction of ammonia with hydroxyl radicals in a rare gas matrix [Zins & Krim, 2014, 69th ISMS]. A step further, the synthesis of the simplest amino-acids, glycine (NH2CH2COOH) and L- or D-alanine (NH2CH3CHCOOH) has already been obtained via reactions in the gas phase involving NH2OH+ [Blagojevic & al. MNRAS 2003].In addition to several earlier models demonstrating that the formation of all these molecules is possible in the gas phase, a new recent three-phase gas-grain chemical kinetics model of hot cores [Garrod ApJ 2013] shows that the results of ammonia oxidation we obtain are plausible by surface/volume reactions.Although none of the aforementioned molecules (except glycine in a sample of cometary origin) has been yet detected in the IS, they all are considered by many observers and modelers as likely

  20. Ecology of larval mosquitoes, with special reference to Anopheles arabiensis (Diptera: Culcidae) in market-garden wells in urban Dakar, Senegal.

    PubMed

    Robert, V; Awono-Ambene, H P; Thioulouse, J

    1998-11-01

    The urban area of Dakar, Senegal, contains > 5,000 market-garden wells that provide permanent sites for mosquito larvae, in particular Anopheles arabiensis Patton, the major vector of malaria. A study of the bioecology of mosquito larvae was conducted over 1 yr with a monthly visit to 48 of these wells. Overall, 9,589 larvae were collected of which 80.1% were Culicinae and 11.9% Anophelinae. Larvae from stages III and IV (n = 853) were identified to 10 species. An. arabiensis represented 86% of the anophelines collected and An. ziemanni Grunberg 14%. The most common Culicinae species included Aedeomyia africana Neveu-Lemaire, Culex quinquefasciatus Say, and Mimomyia splendens Theobald. Maximum anopheline abundance was observed at the end of the dry season in June, whereas maximum Culicinae abundance was observed at the end of the rainy season in September. Most wells (67%) did not harbor any An. arabiensis larvae and in the remaining 33% the larval abundance was low, averaging 0.54 larvae in stages III-IV per tray sample. To identify factors that determine the abundance of larvae in these wells, a co-inertia (multivariate) analysis was carried out to account for physicochemical variables (depth, turbidity, temperature, pH, conductivity, Na+, Cl-, HCO3-, CO3--, and NO3- concentrations) and biological variables (abundance of mosquito species, predators [e.g., fish, Dytiscidae, Notonectidae, odonates], molluscs [Bulinus and Biomphalaria], and surface plants [water lettuce, Lemna, and filamentous algae]). The co-inertia analysis indicated that the abundance of An. arabiensis was associated with Cx. quinquefasciatus and Cx. decens for the physiochemical data but was not associated with other mosquito species for floro-faunistic data. The conditions associated with abundant An. arabiensis were warm temperature (28-30 degrees C), clear and not too deep water (< 0.5 m), elevated concentrations of HCO3- and CO3--, low concentrations of NO3- and NaCl, low populations of

  1. Loss of diacylglycerol kinase epsilon in mice causes endothelial distress and impairs glomerular Cox-2 and PGE2 production.

    PubMed

    Zhu, Jili; Chaki, Moumita; Lu, Dongmei; Ren, Chongyu; Wang, Shan-Shan; Rauhauser, Alysha; Li, Binghua; Zimmerman, Susan; Jun, Bokkyoo; Du, Yong; Vadnagara, Komal; Wang, Hanquin; Elhadi, Sarah; Quigg, Richard J; Topham, Matthew K; Mohan, Chandra; Ozaltin, Fatih; Zhou, Xin J; Marciano, Denise K; Bazan, Nicolas G; Attanasio, Massimo

    2016-05-01

    Thrombotic microangiopathy (TMA) is a disorder characterized by microvascular occlusion that can lead to thrombocytopenia, hemolytic anemia, and glomerular damage. Complement activation is the central event in most cases of TMA. Primary forms of TMA are caused by mutations in genes encoding components of the complement or regulators of the complement cascade. Recently, we and others have described a genetic form of TMA caused by mutations in the gene diacylglycerol kinase-ε (DGKE) that encodes the lipid kinase DGKε (Lemaire M, Fremeaux-Bacchi V, Schaefer F, Choi MR, Tang WH, Le Quintrec M, Fakhouri F, Taque S, Nobili F, Martinez F, Ji WZ, Overton JD, Mane SM, Nurnberg G, Altmuller J, Thiele H, Morin D, Deschenes G, Baudouin V, Llanas B, Collard L, Majid MA, Simkova E, Nurnberg P, Rioux-Leclerc N, Moeckel GW, Gubler MC, Hwa J, Loirat C, Lifton RP. Nat Genet 45: 531-536, 2013; Ozaltin F, Li BH, Rauhauser A, An SW, Soylemezoglu O, Gonul II, Taskiran EZ, Ibsirlioglu T, Korkmaz E, Bilginer Y, Duzova A, Ozen S, Topaloglu R, Besbas N, Ashraf S, Du Y, Liang CY, Chen P, Lu DM, Vadnagara K, Arbuckle S, Lewis D, Wakeland B, Quigg RJ, Ransom RF, Wakeland EK, Topham MK, Bazan NG, Mohan C, Hildebrandt F, Bakkaloglu A, Huang CL, Attanasio M. J Am Soc Nephrol 24: 377-384, 2013). DGKε is unrelated to the complement pathway, which suggests that unidentified pathogenic mechanisms independent of complement dysregulation may result in TMA. Studying Dgke knockout mice may help to understand the pathogenesis of this disease, but no glomerular phenotype has been described in these animals so far. Here we report that Dgke null mice present subclinical microscopic anomalies of the glomerular endothelium and basal membrane that worsen with age and develop glomerular capillary occlusion when exposed to nephrotoxic serum. We found that induction of cyclooxygenase-2 and of the proangiogenic prostaglandin E2 are impaired in Dgke null kidneys and are associated with reduced expression of the

  2. Depth Seismic-Migration Modeling Offshore `Tierra Del Fuego', Argentina (54° 25' S)

    NASA Astrophysics Data System (ADS)

    Comínguez, A. H.; Flores, J.; Tassone, A.

    2007-05-01

    Within the framework of the TESAC Project (Tectonic Evolution of the South America-Scotia plate boundary during the Cenozoic), about 900 km of multichannel seismic reflection profiles were acquired off the Atlantic coast of the Tierra del Fuego Island. The profiles cut across the South America-Scotia plate boundary, a transform margin which traverses in an E-W direction the Island. Data processing and interpretation of a seismic reflection profile is presented in this contribution. A robust post-stack technique involved depth-migration of the seismic section, using an interval-velocity model of the upper Crust adjusted by iterative processing. An interpreted seismic- velocity section (which trends roughly NW-SE), shows a complex superposition of different tectonic structures, with presence of extensional, compressional and transtensional features in the area located to the north of Isla de los Estados. The profile, which crosses the offshore part of the Magallanes fold-and-thrust belt, images the deep structural framework of part of this tectonic province. The identification of acoustic fabrics and seismic discontinuities allowed us to recognize four main units. Overlaying the acoustic basement (Seismic unit 1), there is another unit (Seismic unit 2) which exhibits some reflector packages of high amplitude; this unit must be related to the volcanic and volcaniclastic sequences of Tobífera/Lemaire Fms. The Seismic Unit 3 displays internal reflector configurations of moderate amplitude and continuity and low-to-moderate frequency; the Yaghán/Beauvoir Fms must be the onshore equivalent of this unit. An uppermost seismic layer (Unit 4) may be correlated with the Tertiary sediments of the Magallanes foreland basin which were involved in the fold and thrust belt. A major structure identified in the studied seismic profile is a SE structural high (which involves the units 1, 2 and 3) and a NW down-faulted area. The latter display folds of kilometric size (3-4 km

  3. Mineralogical, IR-spectral and geochemical monitoring of hydrothermal alteration in a deformed and metamorphosed Jurassic VMS deposit at Arroyo Rojo, Tierra del Fuego, Argentina

    NASA Astrophysics Data System (ADS)

    Biel, C.; Subías, I.; Acevedo, R. D.; Yusta, I.; Velasco, F.

    2012-04-01

    The Arroyo Rojo Zn-Pb-Cu volcanogenic massive sulfide deposit is the main deposit of the Fin del Mundo District in the Fuegian Andes, Argentina. This deposit is hosted by a Middle Jurassic volcanic and volcanoclastic sequence forming the Lemaire Formation. The latter consists, from the base up, of the following: rhyolitic and dacitic porphyritic rocks, ignimbrite, tuff, and flow. It is underlain by a pre-Jurassic basement and overlain by the hyaloclastic andesites of the Yahgán Formation. The Arroyo Rojo consists of stacked lenticular lenses that are associated with disseminated mineralization in both the footwall and the hanging wall. The internal structure of the ore lenses is marked by the occurrence of massive, semi-massive and banded facies, along with stringer and brecciated zones and minor ore disseminations. The mineral assemblage comprises mainly pyrite and sphalerite, with minor amounts of galena and chalcopyrite and rare pyrrhotite, arsenopyrite, tetrahedrite and bournonite. The ores and the volcanic host rocks have metamorphosed to greenschist facies and were overprinted by a penetrative tectonic foliation, which led to the development of mylonitic, and cataclastic textures, recrystallization and remobilization. Primary depositional characteristics and regional and hydrothermal alteration patterns were preserved despite deformation and metamorphism. Therefore, primary banding was preserved between facies boundaries. In addition, some remnants of magmatic origin are recognizable in preserved phenocrysts and volcaniclastic phenoclasts. Most of the volcanic and volcaniclastic rocks of the host sequence show a rhyolitic to rhyo-dacitic composition. Regional seafloor alteration, characterized by the presence of clinozoisite, Fe-chlorite and titanite, along with quartz and albite, is partially obliterated by hydrothermal alteration. The hydrothermal alteration is stratabound with the following assemblages, which developed from the base to top: (1) Quartz

  4. Magnetotail-Ionosphere Coupling in a Steady Magnetospheric Convection Flow Brake

    NASA Astrophysics Data System (ADS)

    Lotko, W.; Zhang, B.; Brambles, O. J.

    2010-12-01

    The interaction between the magnetotail and ionosphere in a region of reconnection flow braking is analyzed in a global (LFM) MHD simulation. The simulation includes electrostatic coupling at the low-altitude simulation boundary using the ionospheric Ohm’s law, current continuity, mapping of field-aligned current through the MI gap region with allowance for a field-aligned potential drop, and the effects of electron precipitation using the Knight-Fridman-Lemaire formulation for the number and energy fluxes of precipitating electrons in the Robinson et al (1987) empirical relations for dependence of Pedersen and Hall conductances on auroral precipitation. The simulation is driven by constant SW/IMF conditions with Vsw = 400 km/s, Nsw = 5/cc, and Bz = - 10 nT. It settles into a quasi-stationary, steady magnetospheric convection (SMC) state after an initiating substorm. The magnetotail and braking of the reconnection flow in the SMC state exhibit significant dawn-dusk asymmetry due to the interaction with the ionosphere, which also exhibits dawn-dusk asymmetry due to the effects of intense electron precipitation in the pre-midnight region of upward field-aligned current. These strong asymmetries in the magnetosphere and ionosphere disappear when the ionospheric Hall conductance is treated as constant. The electromagnetic dynamo (local magnetotail Jy < 0) produced by braking of the more intense, duskside reconnection flow powers ionospheric Joule dissipation in a pre-midnight (Bostrom) Type 1 auroral current circuit, which develops at the poleward edge of the conductance gradient in the nightside convection throat. Hall currents are diverted into field-aligned currents in this region as the convection streamlines begin to turn sunward (see figure). Hall currents also connect these field-aligned currents to the R2 current dynamo that projects from the inner magnetosphere to lower latitudes. Large Alfvénic Poynting fluxes flow into the premidnight auroral zone from

  5. First Principles Simulation of the Energetics, Structure and Effect of the 'Titanium-Clinohumite' Defect in Forsterite

    NASA Astrophysics Data System (ADS)

    Walker, A. M.; Berry, A. J.; Hermann, J.; O'Neill, H. S.

    2005-12-01

    hydrated magnesium vacancies on the smaller of the two magnesium sites. (iii) The reaction of titanium and the hydrated cation vacancy is thermodynamically favoured, and results in the formation of a cluster of point defects with six-coordinated titanium on a magnesium site adjacent to a vacant silicon site containing two hydrogen ions. The existence of this configuration is supported by XANES and IR data. The calculations provide an atomic scale view of the naturally occurring hydrogen defect in olivine, which permits conclusions about the effect of hydrogen on, for example, electrical conductivity and cation mobility, to be assessed. References: [1] Matveev, O'Neill, Ballhaus, Taylor and Green (2001), J. Petrol., 42 721-729; [2] Lemaire, Kohn and Brooker (2004), Contrib. Miner. Petrol., 147 48-57; [3] Berry, Hermann, O'Neill and Foran (in press), Geology; [4] Soler, Artacho, Gale, Garcí-a, Junquera, Ordejón and Sánchez-Portal (2002), J. Phys. Conden. Mat., 14 2745-2776.

  6. High hydrostatic pressure influences the in vitro response to xenobiotics in Dicentrarchus labrax liver.

    PubMed

    Lemaire, Benjamin; Mignolet, Eric; Debier, Cathy; Calderon, Pedro Buc; Thomé, Jean Pierre; Rees, Jean François

    2016-04-01

    Hydrostatic pressure (HP) increases by about 1 atmosphere (0.1MPa) for each ten-meter depth increase in the water column. This thermodynamical parameter could well influence the response to and effects of xenobiotics in the deep-sea biota, but this possibility remains largely overlooked. To grasp the extent of HP adaptation in deep-sea fish, comparative studies with living cells of surface species exposed to chemicals at high HP are required. We initially conducted experiments with precision-cut liver slices of a deep-sea fish (Coryphaenoides rupestris), co-exposed for 15h to the aryl hydrocarbon receptor (AhR) agonist 3-methylcholanthrene at HP levels representative of the surface (0.1MPa) and deep-sea (5-15MPa; i.e., 500-1500m depth) environments. The transcript levels of a suite of stress-responsive genes, such as the AhR battery CYP1A, were subsequently measured (Lemaire et al., 2012; Environ. Sci. Technol. 46, 10310-10316). Strikingly, the AhR agonist-mediated increase of CYP1A mRNA content was pressure-dependently reduced in C. rupestris. Here, the same co-exposure scenario was applied for 6 or 15h to liver slices of a surface fish, Dicentrarchus labrax, a coastal species presumably not adapted to high HP. Precision-cut liver slices of D. labrax were also used in 1h co-exposure studies with the pro-oxidant tert-butylhydroperoxide (tBHP) as to investigate the pressure-dependence of the oxidative stress response (i.e., reactive oxygen production, glutathione and lipid peroxidation status). Liver cells remained viable in all experiments (adenosine triphosphate content). High HP precluded the AhR agonist-mediated increase of CYP1A mRNA expression in D. labrax, as well as that of glutathione peroxidase, and significantly reduced that of heat shock protein 70. High HP (1h) also tended per se to increase the level of oxidative stress in liver cells of the surface fish. Trends to an increased resistance to tBHP were also noted. Whether the latter observation truly

  7. In-flight calibration/validation of the ENVISAT/MWR

    NASA Astrophysics Data System (ADS)

    Tran, N.; Obligis, E.; Eymard, L.

    2003-04-01

    Retrieval algorithms for wet tropospheric correction, integrated vapor and liquid water contents, atmospheric attenuations of backscattering coefficients in Ku and S band, have been developed using a database of geophysical parameters from global analyses from a meteorological model and corresponding simulated brightness temperatures and backscattering cross-sections by a radiative transfer model. Meteorological data correspond to 12 hours predictions from the European Center for Medium range Weather Forecasts (ECMWF) model. Relationships between satellite measurements and geophysical parameters are determined using a statistical method. The quality of the retrieval algorithms depends therefore on the representativity of the database, the accuracy of the radiative transfer model used for the simulations and finally on the quality of the inversion model. The database has been built using the latest version of the ECMWF forecast model, which has been operationally run since November 2000. The 60 levels in the model allow a complete description of the troposphere/stratosphere profiles and the horizontal resolution is now half of a degree. The radiative transfer model is the emissivity model developed at the Université Catholique de Louvain [Lemaire, 1998], coupled to an atmospheric model [Liebe et al, 1993] for gaseous absorption. For the inversion, we have replaced the classical log-linear regression with a neural networks inversion. For Envisat, the backscattering coefficient in Ku band is used in the different algorithms to take into account the surface roughness as it is done with the 18 GHz channel for the TOPEX algorithms or an additional term in wind speed for ERS2 algorithms. The in-flight calibration/validation of the Envisat radiometer has been performed with the tuning of 3 internal parameters (the transmission coefficient of the reflector, the sky horn feed transmission coefficient and the main antenna transmission coefficient). First an adjustment of the

  8. Orbiting observatory SOHO finds source of high-speed "wind" blowing from the Sun

    NASA Astrophysics Data System (ADS)

    1999-02-01

    ranging from 30,000 km/h at the surface to over 3 million km/h, the solar wind "grows" much faster than grass". "Looking at the spot where the solar wind actually appears is extremely important", says co-author Dr. Philippe Lemaire of the Institut d'Astrophysique Spatiale in Orsay, France. The Solar Ultraviolet Measurements of Emitted Radiation (SUMER) spectrometer on SOHO detected the solar wind by observing the ultraviolet spectrum over a large area of the solar north polar region. The SUMER instrument was built under the leadership of Dr. Klaus Wilhelm at the Max-Planck-Institut für Aeronomie in Lindau, Germany, with key contributions from the Institut d'Astrophysique Spatiale in Orsay, France, the NASA Goddard Space Flight Center in Greenbelt, Maryland, and the University of California at Berkeley, with financial support from German, French, US and Swiss national agencies. "Identification of the detailed structure of the source region of the fast solar wind is an important step in solving the solar wind acceleration problem. We can now focus our attention on the plasma conditions and the dynamic processes seen in the corners of the magnetic field structures", says Dr. Wilhelm, also co-author of the Science paper. A spectrum results from the separation of light into its component colours, which correspond to different wavelengths. Blue light has a shorter wavelength and is more energetic than red. A spectrum is similar to what is seen when a prism separates white light into a rainbow of distinct colours. By analysing light this way, astronomers learn a great deal about the object emitting the light, such as its temperature, chemical composition, and motion. The ultraviolet light observed by SUMER is actually invisible to the human eye and cannot penetrate the Earth's atmosphere. The hot gas in the solar wind source region emits light at certain ultraviolet wavelengths. When the hot gas flows towards Earth, as it does in the solar wind, the wavelengths of the

  9. Seeing Is Believing. Or Is It?

    NASA Astrophysics Data System (ADS)

    Moore, John W.

    1999-08-01

    Occasionally I get time to read something other than a scientific journal, book, or manuscript. On one such foray I discovered Kenneth Brower's "Photography in the Age of Falsification", which appeared in The Atlantic Monthly in May 1998. Brower described how an editor, who might never have experienced the wildness of nature, could conceive a photograph and assign a photographer to create it. Whether the scene depicted was actually possible often seemed relatively unimportant. The main thing was whether the image would interest viewers. Brower argued that today's vast array of software for manipulating digital versions of photographic images enables what he calls "photofakery" on an unprecedented scale. He described how editors at National Geographic decided to pull an ad that depicted a polar bear in Antarctica (where there are no bears); the ad had been created by digitally superimposing a photograph of a bear in a Cincinnati zoo and a photograph of the Lemaire Channel in Antarctica. According to Brower, "Too few photographers, I think, appreciate how directly the new technology aims at the heart of the credibility that distinguishes this art form from others." Credibility is also one of the hallmarks of science. Science progresses as a result of consensus on what results can be expected from carefully designed and carefully executed experiments and observations. As teachers of chemistry, we have a duty not to fall into the same kinds of traps that have made some photographers uneasy about their profession. And we need to help our students learn to avoid these traps. But it is not that easy, because we also need to capture students' attention and try to make our subject interesting by telling stories or showing phenomena or models that appeal to the imagination. As in the case of photography, defining where imagination begins to usurp reality is difficult. It is therefore a very important issue to wrestle with.