Generation of Radiation Patterns Equivalent to In-Flight Measurements

2021 ◽  
Vol 35 (11) ◽  
pp. 1298-1299
Author(s):  
Ruben Ortega ◽  
Lauren Jugler ◽  
Yaseman Shiri ◽  
Saad Tabet
Keyword(s):  
Great Circle ◽  
The Other ◽  
Post Processing ◽  
Radiation Patterns ◽  
Bank Angle ◽  
Antenna Radiation ◽  
Other Hand ◽  
Flight Measurements ◽  
Generation Of Radiation

Comparison of in-situ measured antenna radiation patterns (RPs) to modeled ones is vital for validation of both. Inflight measured RPs do not always produce a standard conic or elevation cut (constant θ or ϕ angle, respectively), but rather Great Circle (GC) cuts at the aircraft bank angle of interest. WIPL-D’s post-processing routines, on the other hand, do not produce GC cuts in normal setups. A manipulation of the aircraft orientation in xyz-coordinates is required to accomplish this task. Under standard conditions in WIPL-D, the fuselage is positioned parallel to the x-axis and the wings parallel to the y-axis. A model rotation of 90° with respect to the y-axis allows for the generation of GC cuts, where θ and ϕ swap roles. This makes comparison between in-flight measurements and computed data cumbersome. This paper investigates several options to produce non-standard RPs in WIPL-D and MATLAB (using WIPL-D results) that are equivalent to those of in-flight measurements.

Did Ground Cover Change Over Geologic Time?

2000 ◽  
Vol 6 ◽  
pp. 171-182 ◽  
Author(s):  
Ben A. LePage ◽  
Hermann W. Pfefferkorn
Keyword(s):  
Fossil Record ◽  
Ground Cover ◽  
The Other ◽  
Detailed Account ◽  
Geologic Time ◽  
The Past ◽  
Other Hand ◽  
Plant Fossil

When one hears the term “ground cover,” one immediately thinks of “grasses.” This perception is so deep-seated that paleobotanists even have been overheard to proclaim that “there was no ground cover before grasses.” Today grasses are so predominant in many environments that this perception is perpetuated easily. On the other hand, it is difficult to imagine the absence or lack of ground cover prior to the mid-Tertiary. We tested the hypothesis that different forms of ground cover existed in the past against examples from the Recent and the fossil record (Table 1). The Recent data were obtained from a large number of sources including those in the ecological, horticultural, and microbiological literature. Other data were derived from our knowledge of Precambrian life, sedimentology and paleosols, and the plant fossil record, especially in situ floras and fossil “monocultures.” Some of the data are original observations, but many others are from the literature. A detailed account of these results will be presented elsewhere (Pfefferkorn and LePage, in preparation).

II.—On upright Equisetites Stems in the Oolitic Sandstone in Yorkshire

1913 ◽  
Vol 10 (1) ◽  
pp. 3-7 ◽  
Author(s):  
T. G. Halle
Keyword(s):  
Lower Surface ◽  
Upright Position ◽  
The Other ◽  
Mineral Matter ◽  
Vertical Position ◽  
Other Hand ◽  
Mode Of Occurrence ◽  
Coal Measures

Stems of Ecquisetites columnaris (Brong.) have long been known to occur in a vertical position in the sandstones of the Inferior Oolite on the Yorkshire coast. This mode of occurrence has commonly been held as proving that the stems are preserved in the position in which they once grew, having been buried in situ beneath the layers of sand that accumulated on the spot. On the other hand, it has been argued that the upright position need not be primary; it might be as readily explained if the stems are regarded as drifted and secondarily deposited on the spots where they are now found. It is well known and has been pointed out, particularly in the discussions of the upright stems in the Coal-measures, that a drifting tree often has a tendency to sink in a vertical position, the root-end being heavier because of adhering mineral matter or from some other reason. Phillips describes, in his Geology of the Yorkshire Coast, a locality at High Whitby where upright stems of Equisetites columnaris occur in the sandstone. He continues: “They … are broken off or imperfect above, and seldom reach to the upper surface of the bed; they are also broken off below, but commonly pass to the lower surface; and some of the lower joints nearest the roots are found in the subjacent bed of shale.”

scholarly journals Electrical Potential Difference Measurements in Perfused Single Proximal Tubules of Necturus Kidney

1961 ◽  
Vol 44 (4) ◽  
pp. 679-687 ◽  
Author(s):  
Guillermo Whittembury ◽  
Erich E. Windhager
Keyword(s):  
Electrical Potential ◽  
Proximal Tubules ◽  
The Other ◽  
Potential Difference ◽  
Stopped Flow ◽  
Electrical Potential Difference ◽  
Necturus Maculosus ◽  
Other Hand ◽  
Glomerular Filtrate

Transtubular and peritubular face electrical potential differences (P.D.) of the proximal tubules of the kidney of the amphibian Necturus maculosus have been measured in situ. These measurements have been carried out both under normal conditions, when the tubular fluid originates in the glomerular filtrate, and under conditions when the composition of the tubular fluid has been altered using the stopped flow microperfusion technique. Under normal conditions the transtubular potential difference is 20 mv. (lumen-negative) and the P.D. across the peritubular face is 74 mv. (cell-negative). The P.D. across the luminal face is thus 54 mv. (cell-negative). This electrical asymmetry is not influenced by replacing the normal tubular fluid by NaCl, NaCl + mannitol, or by alteration in the intraluminal pH from 7 to 4. On the other hand, replacement of Na by K or choline and the addition of small amounts of DNP to the perfusate diminish this asymmetry.

scholarly journals The Role of Prosody in the Identification of Persian Sentence Types: Declarative or Wh-question?

2017 ◽  
Vol 3 (1) ◽  
Author(s):  
Zohreh Shiamizadeh ◽  
Johanneke Caspers ◽  
Niels O. Schiller
Keyword(s):  
Native Speakers ◽  
Sentence Type ◽  
Initial Position ◽  
The Other ◽  
Current Experiment ◽  
Frequency Code ◽  
Other Hand ◽  
The One

AbstractIt has been reported that prosody contributes to the identification of utterances which lack lexico-syntactic indicators of interrogativity but do have characteristic prosodic correlates (e.g. Vion and Colas 2006. Pitch cues for the recognition of yes-no questions in French. Journal of Psycholinguistics Research 35. 427–445). In Persian wh-in-situ questions, the interrogativity device (the wh-phrase) does not move to the sentence-initial position, and the pre-wh part is characterized by specific prosodic correlates (Shiamizadeh et al. 2016. Do Persian native speakers prosodically mark wh-in-situ questions? Manuscript submitted for publication). The current experiment investigates the role of prosody in the perception of Persian wh-in-situ questions as opposed to declaratives. To this end, an experiment was designed in which Persian native speakers were asked to choose the correct sentence type after hearing only the pre-wh part of a sentence. We hypothesized that prosody guides perception of wh-in-situ questions independent of wh-phrase type. The results of the experiment corroborate our hypothesis. The outcome is discussed in terms of Ohala´s frequency code, and Bolinger´s claim about the universal dichotomous association between relaxation and declarativity on the one hand and tension and interrogativity on the other hand.

Planetary waves on a rotating sphere

1964 ◽  
Vol 279 (1379) ◽  
pp. 446-473 ◽  
Keyword(s):  
Spherical Harmonics ◽  
Wave Motion ◽  
Great Circle ◽  
The Other ◽  
Wave Number ◽  
Amplitude Function ◽  
Axis Of Rotation ◽  
Other Hand ◽  
Vibrating Membrane ◽  
Asymptotic Forms

Simple solutions are found for barotropic planetary oscillations of a fluid in a β-plane, both in the unbounded plane and in enclosed basins of various shapes. These are com pared with analogous motions of fluid on the surface of a sphere. The motions in a β-plane are considered in part I. It is shown that waves can exist which may be oriented in any horizontal direction; they drift westwards with a velocity β/k 2 , where k = 2π/wavelength is the absolute wave number. The group velocity of these waves makes an angle 2α with the eastward direction, where α is the angle made by the vector wave number. The reflexion of such waves from a fixed boundary is studied; both the wavelength and orientation of the reflected w ave differs from that of the incident wave in general. Westward-drifting motions are typical of motions on an unbounded β-plane. On the other hand, motions in an enclosed basin can be described as a carrier wave modulated by a real amplitude function f(x, y). The equation for f is equivalent to the equation for a vibrating membrane clamped at the boundaries; normal mode solutions can be obtained explicitly for a variety of shapes of basin, including the rectangle, circle and equilateral triangle. Motions on a sphere are considered in part II. On an unbounded sphere the general solutions are spherical harmonics S n (θ', Φ') where (θ', Φ') denote spherical co-ordinates with respect to some pole P not necessarily on the axis of rotation. The motions are propagated by a westward d rift of the pole P ' round a circle of latitude, with angular velocity 2Ω/n(n +1). Solutions in enclosed basins have been found not only when the boundaries of the basin are circles of latitude, but also when the boundaries are meridians of longitude. The validity of the β-plane approximation is investigated, first by determining the asymptotic forms of the surface harmonics w hen the wave number n is high ; secondly by comparing the periods of the lower modes in an enclosed basin on a sphere with the corresponding periods for the β-plane. At high wave numbers the solutions in terms of spherical harmonics do generally reduce to motions satisfying the β-plane equations; but exceptions occur in the neighbourhood of certain caustic lines, where the variation of β must be taken into account. Thus it is possible for a wave motion to be trapped in the neighbourhood of a great-circle, the amplitude falling off rapidly to either side. The plane of this great-circle rotates slowly round the axis of rotation of the sphere. On the other hand, in an enclosed basin centred on the equator some of the lower modes of oscillation agree very well with those derived from the β-plane approximation. Even when the radius of the basin is as great as one quadrant, the periods of the four lowest symmetric modes agree within 10 %.

Study on Specificity and Sensitivity of Oligonucleotide Probes for Fluorescence In Situ Hybridization

2012 ◽  
Vol 518-523 ◽  
pp. 628-631
Author(s):  
Xiao Dan Wang ◽  
Jiang Zhu ◽  
Takashi Someya
Keyword(s):  
Detection Rate ◽  
Oligonucleotide Probe ◽  
The Other ◽  
Oligonucleotide Probes ◽  
Bacterial Strains ◽  
Detection Rates ◽  
Average Value ◽  
Other Hand ◽  
Specificity And Sensitivity

Sixteen bacterial strains were used to analyze the specificity and sensitivity of the commonly used oligonucleotide probe for FISH. The results showed that GAM42a probe was not only hybridized with γ-subclass proteobacteria strains, but also hybridized with other subclass proteobacteria strains. The specificity of GAM42a probe therefore would be improved. On the other hand, the average value of detection rates of ALF1b, HGCGP and LGCGP354B probe was less than 50%. After 10min lysozyme treatment, only the detection rate of LGCGP354B probe was improved.

scholarly journals A Tale of Two Transitions: Unraveling Two Distinct Polymorph Transition Mechanisms in One n-Type Single Crystal for Dynamic Electronics

2021 ◽  
Author(s):  
Daniel W. Davies ◽  
Sang Kyu Park ◽  
Stephen B. Shiring ◽  
Hyunjoong Chung ◽  
Prapti Kafle ◽  
...  
Keyword(s):  
Single Crystal ◽  
Growth Mechanism ◽  
High Performance ◽  
Electron Paramagnetic Resonance Spectroscopy ◽  
Nucleation And Growth ◽  
The Other ◽  
Resonance Spectroscopy ◽  
Other Hand ◽  
Nucleation And Growth Mechanism

Cooperativity is used by living systems to circumvent energetic and entropic barriers to yield highly efficient molecular processes. Cooperative structural transitions involve the simultaneous, concerted displacement of molecules in a crystalline material, in stark contrast to the more typical molecule-by-molecule nucleation and growth mechanism often breaking the single crystallinity. Cooperative transitions have acquired much attention in the research community for their low transition barriers, ultrafast kinetics, and structural reversibility. On the other hand, cooperative transitions are rarely observed in molecular crystals and the molecular origin is not well understood. Single crystals of 2-dimensional quinoidal terthiophene (2DQTT-o-B), a high-performance n-type organic semiconductor, demonstrate two thermally-activated, reversible phase transitions with one exhibiting a cooperative mechanism and the second exhibiting a nucleation and growth mechanism. In situ microscopy, single crystal and grazing incidence X-ray diffraction (GIXD), along with Raman spectroscopy suggest a reorientation of the alkyl side chains results in a cooperative transition behavior. On the other hand, the nucleation and growth transition is coincident with both side chain melting and the emergence of new spin-spin interactions between conjugated cores, confirmed through in situ electron paramagnetic resonance spectroscopy (EPR). This is the first observation of biradical interactions directly initiating a structural transition. Through studying these fundamental mechanisms, we establish alkyl chain conformation and disorder as integral to rationally controlling these polymorphic behaviors for novel electronic applications.

scholarly journals Sexual Dimorphic Distribution of Hypothalamic Tachykinin1 Cells and Their Innervations to GnRH Neurons in the Zebrafish

2021 ◽  
Vol 11 ◽  
Author(s):  
Satoshi Ogawa ◽  
Priveena Nair Ramadasan ◽  
Rachel Anthonysamy ◽  
Ishwar S. Parhar
Keyword(s):  
Direct Action ◽  
Brain Regions ◽  
The Other ◽  
Neurokinin A ◽  
Male And Female ◽  
Other Hand ◽  
Neural Processes ◽  
Confocal Images ◽  
Female Zebrafish

Substance P (SP) and neurokinin A (NKA), encoded by TAC1/Tac1 gene are members of the tachykinin family, which exert their neuromodulatory roles in vertebrate reproduction. In mammals, SP and NKA have been shown to regulate gonadotropin-releasing hormone (GnRH) and luteinizing hormone (LH) secretion via kisspeptin neurons. On the other hand, the role of SP/NKA in the regulation of reproduction in non-mammalian vertebrates is not well known. In the present study, we first localized expression of tac1 mRNA in the brain of male and female zebrafish, Danio rerio. Next, using an antibody against zebrafish tachykinin1 (Tac1), we examined the neural association of SP/NKA neural processes with GnRH3 neurons, and with kisspeptin (kiss2) neurons, in the brains of male and female zebrafish. In situ hybridization showed an apparent male-dominant tac1 expression in the ventral telencephalic area, the anterior and posterior parts of the parvocellular preoptic nucleus, and the suprachiasmatic nucleus. On the other hand, there was female-dominant tac1 expression in the ventral periventricular hypothalamus. Confocal images of double-labeled zebrafish Tac1 and GnRH3 showed associations between Tac1-immunoreactive processes and GnRH3 neurons in the ventral telencephalic area. In contrast, there was no apparent proximity of Tac1 processes to kiss2 mRNA-expressing neurons in the hypothalamus. Lastly, to elucidate possible direct action of SP/NKA on GnRH3 or Kiss2 neurons, expression of SP/NKA receptor, tacr1a mRNA was examined in regions containing GnRH3 or Kiss2 neurons by in situ hybridization. Expression of tacr1a mRNA was seen in several brain regions including the olfactory bulb, preoptic area and hypothalamus, where GnRH3 and Kiss2 cells are present. These results suggest that unlike in mammals, Tac1 may be involved in male reproductive functions via direct action on GnRH3 neurons but independent of kisspeptin in the zebrafish.

Analogues between 2D Linear Equations and Great Circle Sailing

2013 ◽  
Vol 67 (1) ◽  
pp. 101-112 ◽  
Author(s):  
Wei-Kuo Tseng ◽  
Wei-Jie Chang
Keyword(s):  
Linear Equations ◽  
Great Circle ◽  
Basic Algebra ◽  
The Other ◽  
Spherical Triangle ◽  
Other Hand ◽  
Vector Algebra

This paper presents the similarities between equations used for great circle sailing and 2D linear equations. Great circle sailing adopts spherical triangle equations and vector algebra to solve problems of distance, azimuth and waypoints on the great circle; these equations are sophisticated and deemed hard for those unfamiliar with them, whereas on the other hand, 2D linear equations can be solved easily with basic algebra and trigonometry definitions. By pointing out the similarities, readers can quickly comprehend great circle equations and grasp just how similar they are to the corresponding 2D linear equations.

Coupled removal of Rhodamine B and Cu2+ by activating persulfate using micron zero-valent iron

2019 ◽  
Vol 68 (7) ◽  
pp. 535-546 ◽  
Author(s):  
Xiaowei Huo ◽  
Yunxin Liu ◽  
Sijie Liu ◽  
Peng Zhou ◽  
Haishen Li ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Organic Compound ◽  
Rhodamine B ◽  
Zero Valent Iron ◽  
The Other ◽  
Simultaneous Removal ◽  
Other Hand ◽  
The One

Abstract In this study, micron zero-valent iron (ZVI) was used to activate persulfate (PS) for the coupled removal of Rhodamine B (RhB) and Cu2+. It was observed that the removal of RhB could be significantly enhanced with Cu2+ compared with that of the case without Cu2+. In addition, the reaction reduced the RhB by 96% within 10 min, and meanwhile reduced the Cu2+ by 60% within 120 min. Investigation of the mechanism revealed that, on the one hand, Cu2+ species could be turned into Cu0 and Cu+ species; on the other hand, PS and Cu2+ could first accelerate the corrosion of ZVI to release Fe2+. Then, in situ generated Cu+ and Fe2+ further decomposed PS to produce ·SO4− and ·OH, which could take part in the removal of RhB. In addition, the ZVI/PS/Cu2+ system also showed a wider pH working range than the ZVI/PS system. Our study proved that simultaneous removal of heavy metal and organic compound in the ZVI/PS/Cu2+ system was feasible.

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