68 research outputs found
Some Aspects Of Monopoly Power In The United States
Definitions Of Monopoly
A Clear-cut definition of monopoly at the outset of this treatise is most desirable. It is with apologies that the author must confess that such a definition is difficult to find. A description of points of agreeement between various authorities who would define monopoly is offered. A definition of monopoly who would define monopoly is offred.
A definition of monopoly today does bear some resemblance to its original meeting. The word monopoly is traced through the greek nouns and to the two greek words (alone) and (to sell). In English common law the term was applied to legal grant or charter, a patent from the king, which conferred an exclusive privilege of trade or some kind or in some region
The Problem of Under-Ageness of Fourteen Prairie View College Students
In this discourse the writer intends to present the effects of under-ageness and acceleration on fourteen Prairie View College students. It is also the purpose of the writer to show whether under-ageness is advantageous or disadvantageous to these fourteen Prairie View College students. The writer, in securing his information, used the personal investigation method. This method was used because the writer felt that he could secure more reliable and confidential information from his subjects. All of his subjects were located on the college campus which also made it convenient for him to use the personal investigation method. There have been many heated discussions as to what the normal age grade progress for a normal boy or girl should be . For the purpose of this study, six years of age is regarded as the normal age for a first grade pupil. For each additional year spent in school, the normal pupil is expected to complete an additional grade. Advancement at a more rapid rate than indicated is counted accelerated by the number of years the advancement deviates from standard set. Advancement at a less rapid rate than that indicated above is counted as retarded by the number of years the lack of advancement deviates from the standard set
Automatically extracting functionally equivalent proteins from SwissProt
In summary, FOSTA provides an automated analysis of annotations in UniProtKB/Swiss-Prot to enable groups of proteins already annotated as functionally equivalent, to be extracted. Our results demonstrate that the vast majority of UniProtKB/Swiss-Prot functional annotations are of high quality, and that FOSTA can interpret annotations successfully. Where FOSTA is not successful, we are able to highlight inconsistencies in UniProtKB/Swiss-Prot annotation. Most of these would have presented equal difficulties for manual interpretation of annotations. We discuss limitations and possible future extensions to FOSTA, and recommend changes to the UniProtKB/Swiss-Prot format, which would facilitate text-mining of UniProtKB/Swiss-Prot
Symmetry and Topology in Superconductors - Odd-frequency pairing and edge states -
Superconductivity is a phenomenon where the macroscopic quantum coherence
appears due to the pairing of electrons. This offers a fascinating arena to
study the physics of broken gauge symmetry. However, the important symmetries
in superconductors are not only the gauge invariance. Especially, the symmetry
properties of the pairing, i.e., the parity and spin-singlet/spin-triplet,
determine the physical properties of the superconducting state. Recently it has
been recognized that there is the important third symmetry of the pair
amplitude, i.e., even or odd parity with respect to the frequency. The
conventional uniform superconducting states correspond to the even-frequency
pairing, but the recent finding is that the odd-frequency pair amplitude arises
in the spatially non-uniform situation quite ubiquitously. Especially, this is
the case in the Andreev bound state (ABS) appearing at the surface/interface of
the sample. The other important recent development is on the nontrivial
topological aspects of superconductors. As the band insulators are classified
by topological indices into (i) conventional insulator, (ii) quantum Hall
insulator, and (iii) topological insulator, also are the gapped
superconductors. The influence of the nontrivial topology of the bulk states
appears as the edge or surface of the sample. In the superconductors, this
leads to the formation of zero energy ABS (ZEABS). Therefore, the ABSs of the
superconductors are the place where the symmetry and topology meet each other
which offer the stage of rich physics. In this review, we discuss the physics
of ABS from the viewpoint of the odd-frequency pairing, the topological
bulk-edge correspondence, and the interplay of these two issues. It is
described how the symmetry of the pairing and topological indices determines
the absence/presence of the ZEABS, its energy dispersion, and properties as the
Majorana fermions.Comment: 91 pages, 38 figures, Review article, references adde
Organometallic mechanism of action and inhibition of the 4Fe-4S isoprenoid biosynthesis protein GcpE (IspG)
We report the results of a series of chemical, EPR, ENDOR, and HYSCORE spectroscopic investigations of the mechanism of action (and inhibition) of GcpE, E-1-hydroxy-2-methyl-but-2-enyl-4-diphosphate (HMBPP) synthase, also known as IspG, an Fe4S4 cluster-containing protein. We find that the epoxide of HMBPP when reduced by GcpE generates the same transient EPR species as observed on addition of the substrate, 2-C-methyl-D-erythritol-2, 4-cyclo-diphosphate. ENDOR and HYSCORE spectra of these transient species (using 2H, 13C and 17O labeled samples) indicate formation of an Fe-C-H containing organometallic intermediate, most likely a ferraoxetane. This is then rapidly reduced to a ferracyclopropane in which the HMBPP product forms an η2-alkenyl Ï- (or Ï/Ï) complex with the 4th Fe in the Fe4S4 cluster, and a similar âmetallacycleâ also forms between isopentenyl diphosphate (IPP) and GcpE. Based on this metallacycle concept, we show that an alkyne (propargyl) diphosphate is a good (Ki âŒÂ 300 nM) GcpE inhibitor, and supported again by EPR and ENDOR results (a 13C hyperfine coupling of âŒ7 MHz), as well as literature precedent, we propose that the alkyne forms another Ï/Ï metallacycle, an η2-alkynyl, or ferracyclopropene. Overall, the results are of broad general interest because they provide new mechanistic insights into GcpE catalysis and inhibition, with organometallic bond formation playing, in both cases, a key role
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