Antipodal Fix
The female gametophyte of most flowering plants forms four cell types after cellularization, namely synergid cell, egg cell, central cell and antipodal cell. Of these, only the antipodal cells have no established functions, and it has been proposed that in many plants including Arabidopsis, the antipodal cells undergo programmed cell death during embryo sac maturation and prior to fertilization. Here, we examined the expression of female gametophyte-specific fluorescent reporters in mature embryo sacs of Arabidopsis, and in developing seeds shortly after fertilization. We observed expression of the fluorescence from the reporter genes in the three antipodal cells in the mature stage embryo sac, and continuing through the early syncytial endosperm stages. These observations suggest that rather than undergoing programmed cell death and degenerating at the mature stage of female gametophyte as previously supposed, the antipodal cells in Arabidopsis persist beyond fertilization, even when the other cell types are no longer present. The results support the concept that the Arabidopsis female gametophyte at maturity should be considered to be composed of seven cells and four cell types, rather than the previously prevailing view of four cells and three cell types.
antipodal
During antipodal cells PCD, polytene chromosomes rearrangement, segregation of nucleoli components and extrusion of nuclear components occur, cytochrome c is released from the mitochondria and DNA breaks appear. We studied in detail the nuclei of cells of the antipodal complex of wheat embryo sac (Triticum aestivum L.) during programmed cell death (PCD). The antipodal complex has been reported to be formed before double fertilisation of the embryo sac. Polyploidisation leads to the formation of giant polytene chromosomes in the nuclei of antipodal cells. These chromosomes are involved in secretory functions and are important for the development of cellular endosperm. Terminal deoxynucleotidyl transferase dUTP nick end labelling assay and immunodetection revealed DNA breaks in the nuclei and release of cytochrome c from mitochondria into the cytoplasm of antipodal cells during PCD. We used transmission electron microscopy, immunodetection and histochemistry to analyse the characteristic structural changes in the nuclei of antipodal cells during PCD. These included sequential structural changes in the nuclei containing polytene chromosomes, segregation of some components of the nucleolus into the bodies of polytene chromosomes, extrusion of nucleolar components and parts of chromosomes into the cytoplasm of antipodal cells and then into the endosperm coenocyte. The obtained results expand the understanding of the structural changes of plant cells with giant polytene chromosomes during PCD.
The vivaldiAntipodal object creates an antipodal Vivaldi element. Antipodal Vivaldi come under the group of end-fire tapered slot antennas, and such antennas are expected to provide medium gain with less side lobes and wide bandwidth. These antennas are low cost, geometrically simple in shape, and mostly used in wireless communications and radar applications.
These vectors will appear either on the upper or on the lower hemisphere. In order to treat these vectors as axes, i.e. in order to assume antipodal symmetry - one has to use the keyword antipodal.
As a consequence the angle between two axes v1, v2 will always be the smallest angle between the directions v1, v2 and v1, -v2, i.e. it will always be smaller than 90 degree. In the absence of antipodal symmetry we obtain
Due to Friedel's law experimental pole figures always provide antipodal symmetry. One consequence of this fact is that MTEX plots pole figure data always on the upper hemisphere. Moreover if you annotate a certain direction to pole figure data, it is always interpreted as an axis, i.e. projected to the upper hemisphere if necessary
The measurement of the inflationary stochastic gravitational wave background (SGWB) is one of the main goals of future GW experiments. In direct GW experiments, an obstacle to achieving it is the isolation of the inflationary SGWB from the other types of SGWB. In this paper, as a distinguishable signature of the inflationary SGWB, we argue the detectability of its universal property: antipodal correlations, i.e., correlations of GWs from the opposite directions, as a consequence of the horizon reentry. A phase-coherent method has been known to be of no use for detecting the angular correlations in SGWB due to a problematic phase factor that erases the signal. We thus investigate whether we can construct a phase-incoherent estimator of the antipodal correlations in the intensity map. We found that the conclusion depends on whether the inflationary GWs have statistical isotropy or not. In the standard inflationary models with statistical homogeneity and isotropy, there is no estimator that is sensitive to the antipodal correlations but does not suffer from the problematic phase factor. On the other hand, it is possible to find a nonvanishing estimator of the antipodal correlations for inflationary models with statistical anisotropy. SGWB from anisotropic inflation is distinguishable from the other components.
Here, we explore the hypothesis that antipodal ejecta contains sufficient impactor material to explain the observed magnetization of anomalies antipodal to large basins, using high-resolution impact simulations. Previous exploration of antipodal ejecta deposits did not explore the fate of impactor materials5. For moderately oblique impacts we find that antipodal ejecta is dominated by the impact materials, which can have high thermoremanent magnetization (TRM) susceptibility (XTRM) like the chondritic meteorite. Moreover, this ejecta is above the Curie temperature at the time of emplacement and can thus record the magnetic field of the Moon as it cools.
In the main text we argue that unrealistically strong fields would be required to produce the magnetic fields arising from magnetized rocks at antipodal regions at spacecraft altitudes, assuming known lunar materials. To demonstrate this, we start by modeling the strongest anomalies at the Crisium antipode, i.e., the swirls in Fig. 1a box s, as two-dimensional sheets of dipoles (Supplementary Fig. 1a, b). The sheets were generated to take on the same surface area that comprises the swirls, which assumes that the swirls contain the majority of the magnetized material. This assumes the bright soil at swirls is at least partially the result of the magnetic field blocking full solar wind access to the surface39,40,41,42,43. Hence, swirls will have stronger magnetization than adjacent terrain without swirls. We use the mapping of Denevi et al.44 to identify the boundaries of the swirls throughout this paper.
S.W. conducted the formal analysis of the simulations and wrote the original draft with contributions from coauthors. B.C.J. and I.G. gave conceptualization and methodology. I.G., M.R.K. and R.E.M. analyzed the magnetic properties of the antipodal material. T.M.D. developed the software, iSALE-3D and pySALEPlot. All authors contributed to manuscript preparation and the conclusions presented here.
While these lineations do indeed seem consistent with large-scale graben formed as a result of antipodal focusing from Sputnik Planitia, confirming that hypothesis with improved imaging will have to wait until the next time a spacecraft makes it to Pluto. The additional global implications of the presence of a thick ocean and an at least partially hydrated core are also intriguing, as it implies that the interior as well as the exterior of Pluto are both more geologically active than anticipated. The unusual geology of the dwarf planet remains mysterious!
This tool converts coordinates to the antipodal coordinates (on the opposite side of the world). Simply enter the coordinates in one of the boxes and click calculates. It is also possible to do the calculation by dragging the markers or by double clicking on the desired location.
In geography, the antipodes (from Greek: anti- "opposed" and pous "foot") of any place on Earth is the point on the Earth's surface which is diametrically opposite to it. Two points that are antipodal to each other are connected by a straight line running through the centre of the Earth. The antipodal coordinates can easily be calculated. The northing of the coordinate can be switched, so N becomes S and S becomes N, eg. N50 52.123 => S50 52.123. The easting is a little more tricky. There is a 180 degree difference between them, so 180-E becomes W and 180-W becomes E, eg. E005 45.123 => W174 14.877.
The Wikipedia article on tides shows a diagram with a tidal bulge both towards the Moon and on the antipodal point (the Sun isn't included in the diagram). Surely that's wrong - what would cause the antipodal bulge?
Assume that earth is falling to wards the moon. Now, as the force on the point near the moon is the maximum and it has 'fallen' the maximum distance, while the earth 'falls' a lesser distance and the farthest of all, the antipodal point 'falls the least'.
The above figure shows the forces acting on earth due to moon, The top figure shows the actual gravitational forces acting, while the bottom one shows the forces after subtracting the force on the earth itself. That should explain the antipodal bulge. See the wikipedia ariticle in Tidal forces
I am probably going to get slammed for this, because it violates everything we were taught about tidal forces, but the antipodal tide is caused by the centrifugal force created by the Earth's rotation about the earth/moon barycenter, not differential gravitational forces. While the moon's gravity is less on the side of the earth furthest from it, that force is still towards the moon, not away from it.There is a good explanation of this centrifugal force explanation on NOAA's website here. I'll cite some pictures and pertinent text, but this site is a good read for anyone trying to understand the forces responsible for the Earth's tides.Here is a diagram showing the earth and moon's movement around the system's barycenter:And some of the pertinent text:The center of revolution of this motion of the earth and moon around their common center-of-mass lies at a point approximately 1,068 miles beneath the earth's surface, on the side toward the moon, and along a line connecting the individual centers-of-mass of the earth and moon. (see G, Fig. 1) The center-of-mass of the earth describes an orbit (E1, E2, E3..) around the center-of-mass of the earth-moon system (G) just as the center-of-mass of the moon describes its own monthly orbit (M1, M2, M3..) around this same point. 041b061a72
