Influence de l’ecosysteme et du stade de developpement des panicules sur l’androgenese chez le riz

L’étude vise à déterminer l’écosystème et le stade de panicule favorables à l’androgenèse chez le riz sur le site d’ (ex-ADRAO) à M’Bé, Bouaké. Le matériel végétal a consisté en deux variétés deOryza glaberrima (CG 14 et CG 20) et 3 de Oryza sativa de type japonica (WAB 56-50 et TAIPEI 309) et indica (BOUAKE 189). Les cals induites à partir d’anthères sur le milieu N6 modifié contenant 0,5 mg l-1 de kinétine, 2,5 mg l-1 de dichlorophenoxy acétique acide (2,4-D), et 15 % de lait de coco, sont ensuite régénérés sur milieu MS additionné de 1 mg l-1d’acide -naphtalène acétique (ANA) et 4 mg l-1kinétine. Les résultats ont révélé une forte interaction génotype-écosystème. En effet, chaque génotype a eu une bonne réponse en androgenèse avec les anthères provenant de son écosystème habituel de croissance. Ainsi, les glaberrima et les japonica se sont bien comportés en androgenèse, au niveau des plateaux et l'indica dans les bas-fonds. Le stade jeune de la panicule (distance auriculaire entre 7 et 8,8 cm) a été le meilleur stade de prélèvement. Tous stades de panicule et écosystèmes confondus, les meilleurs résultats pour la production de cals et la régénération de plantules a été obtenue avec les sativa comparativement aux glaberrima

Effect of body tilt on the constancy of the stereo vertical

Effect of body tilt on the constancy of the stereo vertica

Satellite-matrix-switched, time-division-multiple-access network simulator

A versatile experimental Ka-band network simulator has been implemented at the NASA Lewis Research Center to demonstrate and evaluate a satellite-matrix-switched, time-division-multiple-access (SMS-TDMA) network and to evaluate future digital ground terminals and radiofrequency (RF) components. The simulator was implemented by using proof-of-concept RF components developed under NASA contracts and digital ground terminal and link simulation hardware developed at Lewis. This simulator provides many unique capabilities such as satellite range delay and variation simulation and rain fade simulation. All network parameters (e.g., signal-to-noise ratio, satellite range variation rate, burst density, and rain fade) are controlled and monitored by a central computer. The simulator is presently configured as a three-ground-terminal SMS-TDMA network

Efektivitas Art Therapy Dalam Mengurangi Kecemasan Pada Remaja Pasien Leukemia

Leukemia adalah jenis kanker yang paling banyak dialami oleh anak-anak di bawah usia 16 tahun. Ketika remaja, didiagnosis menderita leukemia, ada beberapa reaksi emosional yang menyertainya, salah satunya adalah kecemasan. Kecemasan pada remaja penderita leukemia ini diukur dengan Hamilton Rating Scale for Anxiety (HRS-A), Revised Childrens Manifest Anxiety Scale (RCMAS), dan melihat gejala kecemasan dari segi fisik, kognitif, serta tingkah laku. Penelitian ini menggunakan metode kualitatif untuk menggambarkan kecemasan remaja penderita leukemia dan metode kuantitatif untuk melihat efektivitas art therapy dalam mengurangi kecemasan pada remaja penderita leukemia. Subjek dalam penelitian ini adalah 5 remaja penderita leukemia dengan 2 subjek diberikan art therapy. Teknik pengambilan sampel dengan menggunakan metode purposive sampling. Pemberian art therapy pada subjek 1 sebanyak 22 sesi dan subjek 2 sebanyak 24 sesi. Dalam penelitian ini, art therapy telah terbukti efektif mengurangi kecemasan pada remaja penderita leukemia dengan menunjukkan Perubahan ke arah yang positif pada keduanya. Keberhasilan art therapy ini juga dipengaruhi oleh dukungan dari keluarga dan lingkungan

The development of turbulent pipe flow

Whilst turbulence still remains one of the great mysteries of classical physics, its reputation for a chaotic lack of structure is under intense scrutiny. Research now points to the existence of highly organized large-scale structures within turbulent flows. Much of this research have almost exclusively been carried out within a so called fully-developed region of flow. This region is downstream of a point beyond which the flow field’s behavior is invariant. However, it has not been conclusively proven that a fully developed region actually exists. A literature survey found that most facilities are cited as being ‘sufficiently long’, yet no formal definition or documentary evidence of the fully developed condition is widely accepted. The aim of the study is to produce a detailed analysis of the flow from the uniform inlet conditions through to the fully-developed turbulent state, along with an accurate definition of what constitutes fully developed flow. This investigation concerns the affect of both the growth of large-scale structures and their role in the evolution of the flow to the fully-developed condition. With the increasing acceptance of the turbulent large-scale structures model, previous research has not yet shown how large-scale structures affect this development length. These aims were achieved by the design, development and deployment of a carriage to transport hot-wires within the pipe allowing measurements at any stream wise point within the working sectio

Comparative Study of the Mechanical Strength in Two Species of Ferns: Polystichum munitum and Pteridium aquilinum

A comparative study of the mechanical strength in two species of ferns, the winter deciduous Pteridium aquilinum and the evergreen Polystichum munitum, was done. The mechanical strength of the leaf and stipe were used as a means for comparison. Additional data such as specific leaf mass (g/cm2) were also collected. The first hypothesis was that the evergreen fern would have higher leaf mechanical strength, while the second hypothesis was that there would be no difference in the mechanical strength of the stipe. The mechanical strength of the stipe was compared through the Modulus of Elasticity (MOE), while the leaf tensile strength was contrasted through the Modulus (Automatic) – both quantities having been determined with the Instron. The former comparison yielded a P-value of 0.1299 (P\u3e0.05) for an unpaired t-test for equal variance, and the latter yielded

Chemo-dynamics of outer halo dwarf stars, including \textit{Gaia}-Sausage and \textit{Gaia}-Sequoia candidates

The low-metallicity, kinematically interesting dwarf stars studied by Stephens \& Boesgaard (2002, SB02) are re-examined using Gaia DR2 astrometry, and updated model atmospheres and atomic line data. New stellar parameters are determined based on the Gaia DR2 parallactic distances and Dartmouth Stellar Evolution Database isochrones. These are in excellent agreement with spectroscopically determined stellar parameters for stars with [Fe/H]$>-2$; however, large disagreements are found for stars with [Fe/H]$\le-2$, with offsets as large as $\Delta$T$_{\rm eff}\sim+500$ K and $\Delta$log\,$g\sim+1.0$. A subset of six stars (test cases) are analysed ab initio using high resolution spectra with Keck HIRES and Gemini GRACES. This sub-sample is found to include two $\alpha$-challenged dwarf stars, suggestive of origins in a low mass, accreted dwarf galaxy. The orbital parameters for the entire SB02 sample are re-determined using \textit{Gaia} DR2 data. We find 11 stars that are dynamically coincident with the \textit{Gaia}-Sausage accretion event and another 17 with the \textit{Gaia}-Sequoia event in action space. Both associations include low-mass, metal-poor stars with isochrone ages older than 10 Gyr. Two dynamical subsets are identified within \textit{Gaia}-Sequoia. When these subsets are examined separately, a common knee in [$\alpha$/Fe] is found for the \textit{Gaia}-Sausage and high energy \textit{Gaia}-Sequoia stars. A lower metallicity knee is tentatively identified in the \textit{Gaia}-Sequoia low energy stars. If the metal-poor dwarf stars in these samples are true members of the \textit{Gaia}-Sausage and \textit{Gaia}-Sequoia events, then they present a unique opportunity to probe the earlier, more pristine, star formation histories of these systems.Comment: 20-21 pages, 20 figures, accepted for publication in MNRA

Early and rapid prediction of patency of the infarct-related coronary artery by using left ventricular wall thickness as measured by two-dimensional echocardiography

AbstractObjectives. The aim of this study was to determine whether echocardiography can distinguish between persistent coronary occlusion and reperfusion.Background. There are no adequate clinical or noninvasive laboratory markers to accurately predict successful reperfusion in an acute myocardial infarction.Methods. In a closed chest swine model, the effect of reperfusion on myocardial wall thickness was studied by comparing a 150-min total coronary artery occlusion (group 1) with 120 min of occlusion followed by 30 min of reperfusion (group 2) in the area of risk as measured by echocardiography. Wall thickness was measured at baseline and at 90 and 150 min.Results. In group 1 (n = 4), there was no appreciable change in mean wall thickness from 90 min to 150 min of occlusion at either end-diastole or end-systole (0.54 ± 0.02 to 0.52 ± 0.03 cm, 0.55 ± 0.03 to 0.54 ± 0.03 cm, respectively; p = NS). In contrast, in group 2 (n = 6), an increase in mean wall thickness from 0.53 ± 0.02 to 0.97 ± 0.05 cm at end-diastole and from 0.56 ± 0.04 to 1.04 ± 0.07 cm at end-systole was found from 90 min of occlusion to 30 min of reperfusion (p < 0.001). Reperfusion resulted. in an increase in wall thickness of 83 ± 11% at end-diastole and 92 ± 17% at end-systole. In contrast, persistent coronary occlusion showed minimal changes of −3.0 ± 5% at end-diastole and −2.0 ± 6% at end-systole.Conclusions. This study confirms the hypothesis that an increase in wall thickness can accurately distinguish between reperfusion and permanent coronary occlusion