4,923 research outputs found
A Different Sort of Normal: Critical Analysis of Five Lesbian Characters’ Coming-out Narratives on Contemporary Television Shows
The spiral of silence and cultivation theories both support the importance of positive lesbian portrayals on television, both for lesbian and heterosexual viewers. Throughout the history of lesbian representation in media, lesbian characters have been both under and misrepresented. This study examined five lesbian characters on recent and current television shows to demonstrate how their portrayals subvert the traditional lesbian representations in media. It is concluded that while Emily Fields, Santana Lopez, Sophie Webster, Emily Fitch, and Naomi Campbell\u27s narratives fall victim to some negative tropes in representation, they are generally revolutionary and powerful storylines, thus increasing positive visibility, providing positive role models for lesbian youths, and helping with a mainstreaming effect leading to greater acceptance socially for GLBT (gay, lesbian, bisexual, transgender) youths
Characterization of Carbon-Contaminated B4C-Coated Optics after Chemically Selective Cleaning with Low-Pressure RF Plasma
Boron carbide (B4C) is one of the few materials that is expected to be mostly
resilient with respect to the extremely high brilliance of the photon beam
generated by free electron lasers (FELs) and is thus of considerable interest
for optical applications in this field. However, as in the case of many other
optics operated at modern light source facilities, B4C-coated optics are
subject to ubiquitous carbon contaminations. These contaminations represent a
serious issue for the operation of high performance FEL beamlines due to severe
reduction of photon flux, beam coherence, creation of destructive interference,
and scattering losses. A variety of B4C cleaning technologies were developed at
different laboratories with varying success. We present a study regarding the
low-pressure RF plasma cleaning of carbon contaminated B4C test samples via
inductively coupled O2/Ar, H2/Ar, and pure O2 RF plasma produced following
previous studies using the same IBSS GV10x downstream plasma source. Results
regarding the chemistry, morphology as well as other aspects of the B4C optical
coating before and after the plasma cleaning are reported. We conclude from
these comparative plasma processes that pure O2 feedstock plasma only exhibits
the required chemical selectivity for maintaining the integrity of the B4C
optical coating.Comment: 27 pages, 15 figure
La distancia que separa las concepciones didácticas de lo que se hace en clase : el caso de los trabajos de laboratorio en biología
En este artículo se analizan las concepciones sobre los trabajos de laboratorio en biología de un grupo de alumnos de 4º año de la escuela secundaria. A través de un cuestionario verbal abierto y una tarea de selección de tarjetas, se indagó qué tipo de trabajos experimentales los alumnos llevan a cabo en sus clases, qué se aprende de ellos y qué posibilidades encuentran en otras modalidades de trabajos experimentales propuestas por los especialistas en didáctica. Los resultados señalan una brecha entre lo que los alumnos refieren que se realiza en sus clases y las propuestas de los especialistas. En la escuela, predominan las tareas escasamente reflexivas (actividades de carácter descriptivo para verificar e ilustrar temas estudiados), que no ayudan a desarrollar habilidades vinculadas con la investigación, ya que exigen seguir una serie de pasos estipulados en vez de alentar el planteamiento de problemas, la formulación de hipótesis, la búsqueda de respuestas y la interpretación de lo observado.Sixteen-year-old students' ideas about Biological laboratory work done in their classes are revealed through an open questionnaire. They were also validated through a selection task in which students were presented four different instructional situations involving practical work and had to decide which was more frequent in their classes, what can be learned through them, and their personal preferences about the way they would like to be taught. The results show a wide gap between what students say they do in their classes and what experts in the field say that should be done. In schools they are taught through non reflective tasks (with only descriptive demands), which rarely help them develop inquiry skills. They are expected to follow the instructions of their teachers instead of posing problems, thinking of hypotheses, trying to find answers and analyzing what they observe
Non-Abelian vortex dynamics: Effective world-sheet action
The low-energy vortex effective action is constructed in a wide class of
systems in a color-flavor locked vacuum, which generalizes the results found
earlier in the context of U(N) models. It describes the weak fluctuations of
the non-Abelian orientational moduli on the vortex worldsheet. For instance,
for the minimum vortex in SO(2N) x U(1) or USp(2N) x U(1) gauge theories, the
effective action found is a two-dimensional sigma model living on the Hermitian
symmetric spaces SO(2N)/U(N) or USp(2N)/U(N), respectively. The fluctuating
moduli have the structure of that of a quantum particle state in spinor
representations of the GNO dual of the color-flavor SO(2N) or USp(2N) symmetry,
i.e. of SO(2N) or of SO(2N+1). Applied to the benchmark U(N) model our
procedure reproduces the known CP(N-1) worldsheet action; our recipe allows us
to obtain also the effective vortex action for some higher-winding vortices in
U(N) and SO(2N) theories.Comment: LaTeX, 25 pages, 0 figure
Reading and Note Taking in Monological and Dialogical Classes in the Social Sciences
This qualitative study explores the uses of reading and note-taking in two pre-service teacher training Social Sciences courses. Data analysis of in-depth interviews with professors and students, class observations and course materials suggested two polar teaching styles according to how bibliography was included in the course and the presence or absence of dialogicality. In one course, the professor assumed that students should read texts on their own prerogative. As monological lectures were given, they mostly studied from their class-notes. In the other course, the professor held class discussions based on readings that took place in and outside the classroom. According to students, this prompted them to use their class-notes to re-signify and consider the relevance of the information read, with talking, reading, and note-taking contextualizing each other. The dialogical teaching style merged literacy practices and interwove them with disciplinary contents, promoting students’ active approach to meaning construction when learning
Hidden local symmetry and color confinement
The hidden local symmetry is a successful model to describe the properties of
the vector mesons in QCD. We point out that if we identify this hidden gauge
theory as the magnetic picture of QCD, a linearized version of the model
simultaneously describes color confinement and chiral symmetry breaking. We
demonstrate that such a structure can be seen in the Seiberg dual picture of a
softly broken supersymmetric QCD. The model possesses exact chiral symmetry and
reduces to QCD when mass parameters are taken to be large. Working in the
regime of the small mass parameters, we show that there is a vacuum where
chiral symmetry is spontaneously broken and simultaneously the magnetic gauge
group is Higgsed. If the vacuum we find persists in the limit of large mass
parameters, one can identify the rho meson as the massive magnetic gauge boson,
that is an essential ingredient for color confinement.Comment: 20 pages, 3 figure
The Spectrum of the 2+1 Dimensional Gauge Ising Model
We present a high precision Monte Carlo study of the spectrum of the
gauge theory in dimensions in the strong coupling phase. Using state of
the art Monte Carlo techniques we are able to accurately determine up to three
masses in a single channel. We compare our results with the strong coupling
expansion for the lightest mass and with results for the universal ratio
determined for the -theory. Finally the whole spectrum is
compared with that obtained from the Isgur-Paton flux tube model and the
spectrum of the dimensional gauge theory. A remarkable agreement
between the Ising and SU(2) spectra (except for the lowest mass state) is
found.Comment: uuencoded latex file of 22 pages plus 4 ps figure
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