scholarly journals Rings with Boolean Lattices of One-Sided Annihilators

Symmetry ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1909
Author(s):  
Małgorzata Jastrzębska
Keyword(s):  
Complete Lattice ◽  
Associative Ring ◽  
The Other ◽  
Nilpotent Ring ◽  
Other Hand ◽  
Complemented Lattices ◽  
Reduced Ring ◽  
Boolean Lattices ◽  
Left And Right

The present paper is part of the research on the description of rings with a given property of the lattice of left (right) annihilators. The anti-isomorphism of lattices of left and right annihilators in any ring gives some kind of symmetry: the lattice of left annihilators is Boolean (complemented, distributive) if and only if the lattice of right annihilators is such. This allows us to restrict our investigations mainly to the left side. For a unital associative ring R, we prove that the lattice of left annihilators in R is Boolean if and only if R is a reduced ring. We also prove that the lattice of left annihilators of R being two-sided ideals is complemented if and only if this lattice is Boolean. The last statement, in turn, is known to be equivalent to the semiprimeness of R. On the other hand, for any complete lattice L, we construct a nilpotent ring whose lattice of left annihilators coincides with its sublattice of left annihilators being two-sided ideals and is isomorphic to L. This construction shows that the assumption of R being unital cannot be dropped in any of the above two results. Some additional results on rings with distributive or complemented lattices of left annihilators are obtained.

ON THE OTHER HAND: THE COSTS AND BENEFITS OF LEFT-HANDEDNESS

2019 ◽  
Vol 17 (1) ◽  
pp. 69-86
Author(s):  
Sarah A. Fritsche ◽  
Annukka K. Lindell
Keyword(s):  
Substance Abuse ◽  
The Other ◽  
Costs And Benefits ◽  
Fitness Costs ◽  
Left Handedness ◽  
Left Handed ◽  
Other Hand ◽  
Lecture Room ◽  
Increased Risk ◽  
Left And Right

Left-handers have been persecuted by right-handers for millennia. This right bias is evident cross-culturally, linguistically (right is literally and figuratively ‘right’, with lefties being described as ‘gauche’, ‘sinister’ and ‘cack-handed’), and environmentally (e.g., equipment design, including power tools, ticket machines, and lecture-room desks). Despite this, the proportion of left-handers has remained constant at approximately 10% of the hominid population, implying that though there are costs associated with left-handedness (if there were not, the proportions of left- and right-handers would be 50:50), left handers must also enjoy fitness advantages that maintain the genes for left-handedness in the population. This paper reviews the costs and benefits of being left-handed, exploring research examining the effects of handedness on brain structure, cognitive function, and human behaviour. The research confirms a variety of left-hander advantages, including some cognitive superiorities, higher wages, and greater sporting and fighting prowess. On the other hand, left-handedness is also associated with significant fitness costs, including an increased risk of accidents, higher substance abuse susceptibility, and earlier death, in comparison with right-handers. In sum, left-handedness confers both costs and benefits, with the latter outweighing the former, maintaining the genes for left-handedness in the population.

The Haptic ‘Oblique Effect’ in Children's and Adults' Perception of Orientation

Perception ◽  
1995 ◽  
Vol 24 (6) ◽  
pp. 631-646 ◽  
Author(s):  
Edouard Gentaz ◽  
Yvette Hatwell
Keyword(s):  
Horizontal Plane ◽  
Haptic Perception ◽  
Sagittal Plane ◽  
Oblique Effect ◽  
The Other ◽  
Older Children ◽  
Other Hand ◽  
Left And Right ◽  
Plane Scanning ◽  
Effect Of Age

The haptic perception of vertical, horizontal, and diagonal orientations was studied in children (aged 7 and 9 years) and in adults. The purpose was to test the hypothesis that the haptic oblique effect results from the different scanning movements at work when one hand explores an oblique standard and the other hand sets the response rod. In experiment 1, blindfolded subjects reproduced the orientation of a standard rod presented in either the frontal, the horizontal, or the sagittal plane, and this task was achieved either ipsilaterally (the same hand explored the standard and set the response rod) or contralaterally (one hand explored the standard and the other hand set the response rod). Since, in the sagittal plane, scanning movements are analogous when the left and right hands explore oblique orientations, no oblique effect should be observed in this condition if the hypothesis is valid. Moreover, a development effect should be observed, since young children generally rely more on movement coding than do older children and adults. Results did not support these predictions: the same oblique effect appeared in the frontal and the sagittal planes both in the ipsilateral and in the contralateral condition, and the effect of age was not in the direction predicted by the hypothesis. The results were consistent with the hypothesis in the horizontal plane only. Experiments 2 and 3 provided further tests of this hypothesis but both failed to support it. Taken together, the results of these three experiments did not support the assumption and it is suggested that the haptic oblique effect may be linked to the gravitational cues provided by the arm—hand system when it acts in the three spatial planes.

QF - 1 Rings of Global Dimension ≦ 2

1973 ◽  
Vol 25 (2) ◽  
pp. 345-352
Author(s):  
Claus Michael Ringel
Keyword(s):  
Global Dimension ◽  
The Other ◽  
Frobenius Rings ◽  
Other Hand ◽  
Dimension 2 ◽  
Left And Right

R. M. Thrall [10] introduced QF — 1, QF — 2 and QF — 3 rings as generalizations of quasi-Frobenius rings. (For definitions, see section 1. It should be noted that all rings considered are assumed to be left and right artinian.) He proved that QF — 2 rings are QF — 3 and asked whether all QF — 1 rings are QF — 2, or, at least, QF — 3. In [9] we have shown that QF — 1 rings are very similar to QF — 3 rings. On the other hand, K. Morita [6] gave two examples of QF — 1 rings, one of them not QF — 2 and therefore not QF — 3, the other one QF — 3, but not QF — 2.

scholarly journals Method to Grasp a Feeling of Being There by Turning a Head Forcibly while Watching a Tourism Video using a VR Headset

Electronics ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 1470
Author(s):  
Naoya Isoyama ◽  
Tsutomu Terada ◽  
Masahiko Tsukamoto
Keyword(s):  
Virtual Reality ◽  
The Other ◽  
Head Mounted Display ◽  
Sense Of Presence ◽  
Other Hand ◽  
Significant Difference ◽  
Perception Of Self ◽  
Left And Right ◽  
Being There ◽  
Self Motion

In virtual reality (VR) tourism, when watching a video of a tourist location, the feeling of presence improves the experience. Furthermore, it is desirable to be able to give a feeling of having been there before to the users visiting the site afterward. In this study, we aimed to reveal the factors that provide these feelings. We hypothesized that one of the factors is the perception of self-motion. Therefore, we proposed a method wherein the users were induced to turn their heads to the left and right when watching the video of a tourist site via a VR head-mounted display. We conducted two experiments and found that the proposed method conveyed the greatest sense of presence. On the other hand, there was no significant difference in giving the feeling of having been there between the proposed method and watching the video of the site on a PC.

scholarly journals The smallest proper congruence on S(X)

1988 ◽  
Vol 30 (3) ◽  
pp. 301-313 ◽  
Author(s):  
K. H. Hofmann ◽  
K. D. Magill
Keyword(s):  
Topological Space ◽  
Complete Lattice ◽  
The Other ◽  
Topological Spaces ◽  
Other Hand ◽  
Dual Atom ◽  
Lattice Of Congruences

S(X) is the semigroup of all continuous self maps of the topological space X and for any semigroup S, Cong(S) will denote the complete lattice of congruences on S. Cong(S) has a zero Z and a unit U. Specifically, Z = {(a, a):a ∈ S} and U = S × S. Evidently, Z and U are distinct if S has at least two elements. By a proper congruence on S we mean any congruence which differs from each of these. Since S(X) has more than one element when X is nondegenerate, we will assume without further mention that the spaces we discuss in this paper have more than one point. We observed in [4] that there are a number of topological spaces X such that S(X) has a largest proper congruence, that is, Cong(S(X)) has a unique dual atom which is greater than every other proper congruence on S(X). On the other hand, we also found out in [5] that it is also common for S(X) to fail to have a largest proper congruence. We will see that the situation is quite different at the other end of the spectrum in that it is rather rare for S(X) not to have a smallest proper congruence. In other words, for most spaces X, Cong(S(X)) has a unique atom which is smaller than every other proper congruence.

Effect of Annona senegalensis leaves on morphometric parameters of reproductive organs in rabbits

2016 ◽  
Vol 5 (3) ◽  
pp. 122-125
Author(s):  
Dougnon Jacques Tossou ◽  
◽  
Ahossi Philippe Kapko ◽  
Soha Sas Arnaud Sèsséya ◽  
Ohouko Okri Fréjus Hans ◽  
...  
Keyword(s):  
Reproductive System ◽  
Live Weight ◽  
Reproductive Organs ◽  
Morphometric Parameters ◽  
The Other ◽  
Control Group ◽  
Other Hand ◽  
Left And Right ◽  
The Right ◽  
Female Reproductive Organs

The present study aimed to evaluate the effect of the leaves of Annona senegalensis on morphometric parameters of the female reproductive organs in rabbits. A total of 120 rabbits were divided into four batches A, B, C and D of 30 animals each. Lots B, C an d D received 10, 20 and 30 g leaves of Annona Senegalensis / kg of feed respectively, while lot A (control group) was fed with the staple feed (without Annona senegalensis leaves). At the end of the experiment, the animals were dissected and morphometric parameters of the different genital organs were measured. The results sho wed that the average live weight, the average lengths of the left oviduct and the average lengths of the vagina did not vary significantly between different experimental groups (p> 0.05). On the other hand, the weight of the right ovary, the left and right uterus, right oviduct, vagina and reproductive system varied significantly between batches (p <0.05). , the right oviduct length of Lot D was the longest (15.52 cm ± 2.83) with a shorter right uterus (5.87 cm ± 1.43) compared to other lots.

A study of cometary eruptions through OH radio-lines

1999 ◽  
Vol 173 ◽  
pp. 249-254
Author(s):  
A.M. Silva ◽  
R.D. Miró
Keyword(s):  
Short Duration ◽  
Growth Curves ◽  
The Other ◽  
Initial Mass ◽  
Radio Lines ◽  
Other Hand ◽  
Sudden Rise

AbstractWe have developed a model for theH2OandOHevolution in a comet outburst, assuming that together with the gas, a distribution of icy grains is ejected. With an initial mass of icy grains of 108kg released, theH2OandOHproductions are increased up to a factor two, and the growth curves change drastically in the first two days. The model is applied to eruptions detected in theOHradio monitorings and fits well with the slow variations in the flux. On the other hand, several events of short duration appear, consisting of a sudden rise ofOHflux, followed by a sudden decay on the second day. These apparent short bursts are frequently found as precursors of a more durable eruption. We suggest that both of them are part of a unique eruption, and that the sudden decay is due to collisions that de-excite theOHmaser, when it reaches the Cometopause region located at 1.35 × 105kmfrom the nucleus.

Closing the GAP—A 5Å Scanning Microscope

1969 ◽  
Vol 27 ◽  
pp. 6-7
Author(s):  
A. V. Crewe
Keyword(s):  
Normal Form ◽  
The Other ◽  
Resolving Power ◽  
Scanning Microscope ◽  
Conventional Microscope ◽  
Other Hand ◽  
Closing The Gap ◽  
Thermal Sources ◽  
Better Than ◽  
Transmission Microscope

We have become accustomed to differentiating between the scanning microscope and the conventional transmission microscope according to the resolving power which the two instruments offer. The conventional microscope is capable of a point resolution of a few angstroms and line resolutions of periodic objects of about 1Å. On the other hand, the scanning microscope, in its normal form, is not ordinarily capable of a point resolution better than 100Å. Upon examining reasons for the 100Å limitation, it becomes clear that this is based more on tradition than reason, and in particular, it is a condition imposed upon the microscope by adherence to thermal sources of electrons.

Life Beyond 1MeV

1980 ◽  
Vol 38 ◽  
pp. 30-33
Author(s):  
K.H. Westmacott
Keyword(s):  
Electron Microscopy ◽  
Past Experience ◽  
The Other ◽  
Good Case ◽  
Other Hand ◽  
The U.S

Life beyond 1MeV – like life after 40 – is not too different unless one takes advantage of past experience and is receptive to new opportunities. At first glance, the returns on performing electron microscopy at voltages greater than 1MeV diminish rather rapidly as the curves which describe the well-known advantages of HVEM often tend towards saturation. However, in a country with a significant HVEM capability, a good case can be made for investing in instruments with a range of maximum accelerating voltages. In this regard, the 1.5MeV KRATOS HVEM being installed in Berkeley will complement the other 650KeV, 1MeV, and 1.2MeV instruments currently operating in the U.S. One other consideration suggests that 1.5MeV is an optimum voltage machine – Its additional advantages may be purchased for not much more than a 1MeV instrument. On the other hand, the 3MeV HVEM's which seem to be operated at 2MeV maximum, are much more expensive.

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