776 research outputs found
Exterior Differentials in Superspace and Poisson Brackets of Diverse Grassmann Parities
It is shown that two definitions for the exterior differential in superspace,
giving the same exterior calculus, when applied to the Poisson bracket lead to
the different results. Examples of the even and odd linear brackets,
corresponding to semi-simple Lie groups, are given and their natural connection
with BRST and anti-BRST charges is indicated.Comment: 5 pages, LATEX 2.09. The talk at the 9th International Conference on
Supersymmetry and Unification of Fundamental Interactions (SUSY'01, JINR,
Dubna, Russia, 11-17 June, 2001). To be published in the Proceedings of this
Conference. Correction of misprint
Degenerate Odd Poisson Bracket on Grassmann Variables
A linear degenerate odd Poisson bracket (antibracket) realized solely on
Grassmann variables is presented. It is revealed that this bracket has at once
three nilpotent -like differential operators of the first, the second
and the third orders with respect to the Grassmann derivatives. It is shown
that these -like operators together with the Grassmann-odd nilpotent
Casimir function of this bracket form a finite-dimensional Lie superalgebra.Comment: 5 pages, LATEX. Corrections of misprints. The relation (23) is adde
Two-step Russian phoneme classification method
Секция 11. Цифровые медиатехнологи
Incontinence-specific quality of life measures used in trials of treatments for female urinary incontinence: a systematic review.
This systematic review examined the use of incontinence-specific QOL measures in clinical trials of female incontinence treatments, and systematically evaluated their quality using a standard checklist.
Of 61 trials included in the review, 58 (95.1%) used an incontinence-specific QOL measure. The most commonly used were IIQ (19 papers), I-QoL (12 papers) and UDI (9 papers). Eleven papers (18.0%) used measures which were not referenced or were developed specifically for the study. The eight QOL measures identified had good clinical face validity and measurement properties.
We advise researchers to evaluate carefully the needs of their specific study, and select the QOL measure that is most appropriate in terms of validity, utility and relevance, and discourage the development of new measures. Until better evidence is available on the validity and comparability of measures, we recommend that researchers consider using IIQ or I-QOL with or without UDI in trials of incontinence treatments
Field Representations of Vector Supersymmetry
We study some field representations of vector supersymmetry with superspin
Y=0 and Y=1/2 and nonvanishing central charges. For Y=0, we present two
multiplets composed of four spinor fields, two even and two odd, and we provide
a free action for them. The main differences between these two multiplets are
the way the central charge operators act and the compatibility with the
Majorana reality condition on the spinors. One of the two is related to a
previously studied spinning particle model. For Y=1/2, we present a multiplet
composed of one even scalar, one odd vector and one even selfdual two-form,
which is a truncation of a known representation of the tensor supersymmetry
algebra in Euclidean spacetime. We discuss its rotation to Minkowski spacetime
and provide a set of dynamical equations for it, which are however not derived
from a Lagrangian. We develop a superspace formalism for vector supersymmetry
with central charges and we derive our multiplets by superspace techniques.
Finally, we discuss some representations with vanishing central charges.Comment: 37 page
Hodge Duality Operation And Its Physical Applications On Supermanifolds
An appropriate definition of the Hodge duality operation on any
arbitrary dimensional supermanifold has been a long-standing problem. We define
a working rule for the Hodge duality operation on the -dimensional supermanifold parametrized by a couple of even (bosonic)
spacetime variables and a couple of Grassmannian (odd)
variables and of the Grassmann algebra. The Minkowski
spacetime manifold, hidden in the supermanifold and parametrized by , is chosen to be a flat manifold on which a two -dimensional
(2D) free Abelian gauge theory, taken as a prototype field theoretical model,
is defined. We demonstrate the applications of the above definition (and its
further generalization) for the discussion of the (anti-)co-BRST symmetries
that exist for the field theoretical models of 2D- (and 4D) free Abelian gauge
theories considered on the four - (and six )-dimensional
supermanifolds, respectively.Comment: LaTeX file, 25 pages, Journal-versio
A Study of Student Teachers' Reflections on Their Beliefs, Thoughts, and Practices
This is the authors' accepted manuscript, post peer-review. The original published version can be found at the following link:http://dx.doi.org/10.1080/01626620.2008.10463482The purposes of this study were to identify critical events that student teachers encountered and to investigate how the interaction between the characteristics of student teachers and their school environment influences their role-assumption strategies. Twenty-seven student teachers (15 elementary and 12 secondary) in three midwestern communities provided data in the form of prepared journal guides, classroom observations, interviews, and questionnaires. Analysis of the data over several phases led to a refined theory of beginning teachers' role-assumption strategies. Perhaps the most significant finding from this study is that the interaction of an individual's needs and perceptions of the salient characteristics of the school and classroom environment results in unique, understandable, and adaptive patterns of behavior aimed not just at the goal of developing competence but at that of contributing to improved school practice. Implications for teacher education, supervision practices, and future research are discussed
The Effect of Condensed Tannins in Lotus spp. on the Lesser Migratory Grasshopper
Hatchling grasshoppers (Melanoplus sanguinipes Fab.) fed one accession of field grown big trefoil (Lotus uliginosis Schkuhr) containing a tannin content of 56 mg. g-1 FW, had a significantly lower mean weight than hatchlings fed field grown Lotus species and accessions with lower tannin content. Adult female grasshoppers fed L. uliginosis foliage with 32.3 mg.g-1 FW tannin also ate more feed and had a 2-fold higher gut trypsin and chymotrypsin activity than adults fed low tannin L. corniculatus foliage (0.13 mg.g-1 FW tannin). In more controlled experiments, growth at 20o C or 30o C was used to increase tannin in rooted cuttings of L. uliginosis to concentrations ranging from 7 to 195 mg.g-1 FW. Hatchling weight decreased as a function of dietary tannin concentration when fed these clones. Both hatchling weight and survival were affected when hatchlings were fed pelleted wheat seedlings supplemented with purified L. uliginosis tannin preparations
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High proliferation and delamination during skin epidermal stratification.
The development of complex stratified epithelial barriers in mammals is initiated from single-layered epithelia. How stratification is initiated and fueled are still open questions. Previous studies on skin epidermal stratification suggested a central role for perpendicular/asymmetric cell division orientation of the basal keratinocyte progenitors. Here, we use centrosomes, that organize the mitotic spindle, to test whether cell division orientation and stratification are linked. Genetically ablating centrosomes from the developing epidermis leads to the activation of the p53-, 53BP1- and USP28-dependent mitotic surveillance pathway causing a thinner epidermis and hair follicle arrest. The centrosome/p53-double mutant keratinocyte progenitors significantly alter their division orientation in the later stages without majorly affecting epidermal differentiation. Together with time-lapse imaging and tissue growth dynamics measurements, the data suggest that the first and major phase of epidermal development is boosted by high proliferation rates in both basal and suprabasally-committed keratinocytes as well as cell delamination, whereas the second phase maybe uncoupled from the division orientation of the basal progenitors. The data provide insights for tissue homeostasis and hyperproliferative diseases that may recapitulate developmental programs
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