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In 2011, 14 Midwest trial locations evaluated tolerance of an AAD-1 and glyphosate-resistant corn hybrid to a 2,4-D choline+glyphosate premix formulation applied single and sequential POST at V4 and/or V7 corn with and without a PRE application of 2,4-D dimethylamine (DMA). Herbicides were applied at 1X and 2X maximum use rates with 1X rates of 1120 g ae ha−1 for glyphosate and 2,4-D DMA and 1065+1120 g ae ha−1 for the 2,4-D choline+glyphosate premix, respectively. Crop response was greatest 2 d after 2X rate applications, resulting in 4 to 10% visible injury to corn across application timings. No brace root injury or effect on corn grain yield were observed.
We have assembled a new sample of some of the most FIR-luminous galaxies in the Universe and have imaged them in 1.1 mm dust emission and measured their redshifts 1 < z < 4 via CO emission lines using the 32-m Large Millimeter Telescope / Gran Telescopio Milimétrico (LMT/GTM). Our sample of 31 submm galaxies (SMGs), culled from the Planck and Herschel all-sky surveys, includes 14 of the 21 most luminous galaxies known, with LFIR > 1014L⊙ and SFR > 104M⊙/yr. These extreme inferred luminosities – and multiple / extended 1.1 mm images – imply that most or all are strongly gravitationally lensed, with typical magnification μ ~ 10 × . The gravitational lensing provides two significant benefits: (1) it boosts the S/N, and (2) it allows investigation of star formation and gas processes on sub-kpc scales.
Our interest in the psychological properties of semen arose as a byproduct of an initial interest in menstrual synchrony. In reviewing that literature we discovered several articles (Trevathan, Burleson, & Gregory, 1993; Weller & Weller, 1998) reporting that lesbians who live together fail to show menstrual synchrony. Since the evidence suggests that menstrual synchrony is mediated by the exchange of subtle olfactory cues among cohabitating women (Preti et al., 1986, Stern & McClintock, 1998) this struck us as peculiar, because lesbians would be expected to be in closer, more intimate contact with one another on a daily basis than other females who live together. What is it about heterosexual females that promotes menstrual synchrony, or conversely what is it about lesbians that prevents menstrual synchrony? It occurred to us that one feature that distinguishes heterosexual women from lesbians is the presence or absence of semen in the female reproductive tract. Lesbians have semen-free sex.
Human semen is a very complicated mixture of many different ingredients. If you extract the sperm from semen, what is left is called seminal plasma. We speculated that there may be chemicals in seminal plasma that, through vaginal absorption, affect female biology and triggers the release of pheromones that function to entrain menstrual cycles among cohabitating women. Some of the components in semen pass through vaginal epithelial tissue, and within an hour or two after intercourse heightened levels of certain seminal chemicals can be detected in the female bloodstream (Benziger & Edelson, 1983).
Among sexually reproducing species, the penis evolved as an internal fertilization device. But across different species, penises exist in a bewildering array of shapes and sizes (see Eberhard, 1985). Among primates, the human penis is distinctive by virtue of both its size and its enlarged glans and protruding coronal ridge (see Gallup & Burch, 2004). There has been some speculation that the human penis evolved not only as an internal fertilization device, but also as a mechanism for displacing semen left by rival males in the female reproductive tract (e.g. Baker & Bellis, 1995).
In a series of studies designed to simulate sexual intercourse under laboratory conditions using artificial genitals, we found that when latex vaginas contained simulated semen, phalluses that approximated the configuration of the human penis displaced 80% or more of the semen by drawing it away from the cervical end of the vagina (Gallup et al., 2003). Through a series of experimental manipulations, we determined that the coronal ridge may be an important feature of the penis in mediating semen displacement. Thus, as a mechanical means of affecting sperm competition, the human penis may enable successive males to displace foreign semen from the female reproductive tract and substitute their semen for those of their rivals.
Preeclampsia is a leading cause of prenatal infant mortality (Mac Gillivray, 1983; Robillard, Dekker, & Hulsey, 2002). Preeclampsia occurs as a consequence of abnormal invasion by the trophoblast in the uterine spiral arteries and endothelial cell dysfunction (Friedman, 1993), and as a consequence the fetus may not receive adequate nutrition resulting in growth retardation. Whereas all mammalian embryos undergo implantation shortly after conception, humans are the only mammalian species known to undergo a second phase of deep trophoblastic implantation at the end of the first trimester (Robillard et al., 2003). In normal development, this second stage of implantation provides for the modification of spiral arteries that result in an increase in the blood flow to the placenta. Preeclampsia is believed to be the result of a failure to achieve or to complete this second implantation phase (Robillard et al., 2003). It is clinically diagnosed by maternal hypertension and proteinuria. The hypertension results from cytotrophic factors that are released by the fetus and serve to increase the amount of blood flowing to the placenta (Haig, 1993).
It has been theorized that the origins of preeclampsia in humans are linked to the increase in cranial capacity associated with the genus Homo (Robillard et al., 2003). The greater nutritional needs of the developing brain in the human fetus, compared to the more modest needs of developing brains in species with lower cranial capacities, has been hypothesized to explain the second wave of implantation characteristic of humans.
This paper presents radiocarbon results from a single Goniastrea favulus coral from Papua New Guinea which lived continuously between 13.0 and 13.1 kyr BP. The specimen was collected from a drill core on the Huon Peninsula and has been independently dated with 230Th. A site-specific reservoir correction has been applied to the results, and coral growth bands were used to calibrate individual growth years. Alternating density bands, which are the result of seasonal growth variations, were subsampled to provide 2 integrated 6-month 14C measurements per year. This allows for 20 independent measurements to be averaged for each decadal value of the 14C calibration, making these results the highest resolution data set available for this brief time range. The finestructure of the data set exhibits 14C oscillations with frequencies on the order of 4 to 10 yr, similar to those observed in modern coral 14C records.
Gordon G. Gallup, Department of Psychology, State University of New York at Albany, Albany, NY, USA,
James R. Anderson, Department of Psychology, University of Stirling, Scotland,
Steven M. Platek, Department of Psychology, Drexel University, Philadelphia, PA, USA
The purpose of this chapter is to review the evidence concerning mirror self-recognition as a measure of self-awareness and examine its applicability to schizophrenia. The evidence suggests that the ability to identify yourself correctly in a mirror is not only related to the capacity to conceive of yourself, but may also be related to your ability to take into account what other individuals may know, want or intend to do. This ability to make accurate inferences about mental states in others (known as mental state attribution, theory of mind or social intelligence) begins to emerge during childhood at the same point in time as mirror self-recognition. Species that fail to recognize themselves in mirrors fail to show any evidence that they can infer mental states in one another. Also consistent with the proposition that these phenomena go hand in hand, recent neuropsychological evidence shows that self-awareness and mental state attribution in humans appear to be a byproduct of brain activity that is related to the frontal cortex. As detailed here and elsewhere in this volume, there is growing evidence that both self-awareness and mental state attribution is impaired in schizophrenic patients and that schizophrenia may be related to frontal lobe dysfunction.
Mirrors have a number of unique psychological properties. In principle, mirrors represent a means of seeing yourself as you are seen by others. In front of a mirror you are literally an audience to your own behaviour.
Numerous searches have failed to identify a single co-occurrence of total blindness and schizophrenia. Evidence that blindness causes loss of certain NMDA-receptor functions is balanced by reports of compensatory gains. Connections between visual and anterior cingulate NMDA-receptor systems may help to explain how blindness could protect against schizophrenia.
Aspects of Northoff's argument lend themselves to the ongoing investigation of localizing the self in the brain. Recent data from the fields of neuropsychology and cognitive neuroscience provide evidence that the right hemisphere is a candidate for localization of self. The data on catatonia further that proposition and add insight into the continuing investigation of self in the brain across sensory and motor domains.
In this chapter we examine some results for four model systems consisting of rings of H atoms. These calculations show how the number of atoms in a complex reaction may influence rates of reaction, particularly through the activation energy. The systems are as follows.
Four H atoms in a rectangular geometry of D2h symmetry. The rectangle is characterized by two distances, RA and RB. We map out a region of the ground state energy for this four-electron system as a function of the two distances.
Six H atoms in a hexagonal geometry of D3h symmetry. This is not a regular hexagon, in general, but, like the system of four H atoms, is characterized by two distances we also label RA and RB. These two distances alternate around the ring. We also calculate the map of the ground state energy for this six-electron system.
Eight H atoms in an octagonal geometry of D4h symmetry and the specific shape characterized by the RA and RB variables as above. For this larger system we only determine the saddle point with respect to the same sort of variables.
Ten H atoms in a decagonal geometry of D5h symmetry and the RA and RB variables. Again, we determine only the saddle point.
Since the geometries of these systems are in most regions not regular polygons, we will symbolize them as (H2)n, emphasizing the number of H2 molecules rather than the total number of atoms.
As was seen in the last chapter, the effect of permutations on portions of the wave function is important in enforcing their correct character. The permutations of n entities form a group in the mathematical sense that is said to be one of the symmetric groups. In particular, when we have all of the permutations of n entities the group is symbolized Sn. In this chapter we give, using the theory of the symmetric groups, a generalization of the special treatment of three electrons discussed above.
There are several more or less equivalent methods for dealing with the twin problems of constructing antisymmetric functions that are also eigenfunctions of the spin. Where orbitals are orthogonal the graphical unitary group approach (GUGA), based upon the symmetric group and unitary group representations, is popular today. With VB functions, which perforce have nonorthogonal orbitals, a significant problem centers around devising algorithms for calculating matrix elements of the Hamiltonian that are efficient enough to be useful. In the past symmetric group methods have been criticized as being overcomplicated. Nevertheless, the present author knows of no other techniques for obtaining what appears to be the optimal algorithm for these calculations.
This chapter is the most complicated and formal in the book. Looking back to Chapter 4 we can obtain an idea of what is needed in general.
Benzene is the archetypal aromatic hydrocarbon and its study has been central to the understanding of aromaticity and resonance from the early times. In addition, it has the physical property of having its π electrons reasonably independent from those in σ bonds, leading early quantum mechanics workers to treat the π electrons alone. Since benzene is a ring and the rules for forming Rumer diagrams have one draw noncrossing lines between orbital symbols written in a circle, the Rumer diagrams correspond to the classical Kekulé and Dewar bond schemes that chemists had postulated far earlier than the VB treatments occurred. This parallel has intrigued people since its first observation and led to many discussions concerning its significance. It has also led to considerable work in more qualitative “graphical methods” for which the reader is directed to the literature. (See, inter alia, Randić.)
We will examine benzene with different bases and also discuss some of the ideas that consideration of this molecule has led to, such as resonance and resonance energy.
We show again the traditional five covalent Rumer diagrams for six electrons and six orbitals in a singlet coupling and emphasize that the similarity between the ring of orbitals and the shape of the molecule considerably simplifies the understanding of the symmetry for benzene.