1,286 research outputs found
Dee-jay drop that deadbeat : hip-hop's remix of fatherhood narratives
Dr. Anand Prahlad, Dissertation Supervisor.Field of Study: English."May 2018."This dissertation examines hip-hop fatherhood narratives from 2010-2015 influenced by drug addiction, mass incarceration, underground economies, trauma, and dysfunctional co-parenting. Explicitly, the paper explores how marginalized, urban African American dads are imagined as protectors, providers, and/or surrogates in hip-hop lyricism. Additionally, the research pays attention to hip-hop artists' depiction of identity orchestration and identity formation of black adolescents and patriarchs by utilizing David Wall's theories on identity stasis. Moreover, the dissertation critically analyzes hip-hop lyrics that reflect different concepts of maleness such as hyper-masculine, the complex cool, biblical, heroic, and hegemonic masculinities. In sum, the paper examines rap lyrics use of mimicry calling into question representative black male engagement with American patriarchy.Includes bibliographical references (pages 234-242)
Relationship of the Surface Structure of Metaphase Chromosomes to the Higher Order Organization of Chromatin Fibers
Scanning electron microscopy (SEM), as well as transmission electron microscopy (TEM), has been utilized to determine how the surface structure of mitotic chromosomes is related to the organization of the 30 nm chromosomal fibers. SEM revealed the surfaces of isolated, HeLa cell chromosomes to possess a knobby substructure with chromosomes prepared for EM in buffers containing 0.5-1.5 mM Mg2+. These projections had substantially greater widths (65-70 nm) than the underlying chromatin fibers. Reducing the Mg ion concentration to 0.05-0.15 mM resulted in the further expansion of the chromosomes, which flattened the chromosomes for SEM so the fibers became the dominant feature of the micrographs. The surface protuberances are interpreted as representing the peripheral tips of radial chromatin loops.
The same procedure of slightly expanding chromosomes by decreasing the Mg2+ concentration in resuspension buffer was also utilized in a TEM, serial sectioning study. Longitudinal sections close to the central chromatid axis showed radially oriented fibers within the planes of the sections. This was replaced by a dot pattern when the longitudinal sections grazed the periphery of the chromatid. Transverse sections displayed more clearly the radial orientation of the fibers.
A consistent picture emerges from applying SEM and TEM that supports the radial loop model for the primary mode of organization of chromatin fibers in metaphase chromosomes
Ternary refrigerant compositions which contain perfluoroorgano sulfur compounds as replacements for R-22
Refrigerant compositions include mixtures of at least three different components, including a fluorinated sulfur-containing compound with at least one of a fluorinated ether or a fluorinated hydrocarbon. Also, methods for cooling a body include compressing such a refrigerant composition and bringing the body into heat transfer relation to it. The disclosed refrigerant compounds have refrigerant-significant properties similar to those of R-22, and they can be employed as drop-in substitutes in refrigeration apparatus designed for R-22 application
Ternary refrigerant compositions containing fluorinated ethers as replacements for R-22
Refrigerant compositions include mixtures of at least three different components, including a fluorinated ether with at least one of a second fluorinated ether, an ether and a fluorinated hydrocarbon. Also, methods for cooling a body include compressing such a refrigerant composition and bringing the body into heat transfer relation to it. The disclosed refrigerant compounds have refrigerant-significant properties similar to those of R-22, and they can be employed in place of or as drop-in substitutes in refrigeration apparatus designed for R-22 application
Function and Structure in Retinal Transplants
Embryonic mammalian donor retina
transplanted into the subretinal space of a
mature host develops into a graft with wellorganized,
but atypical retinal structure. We
tested the effect of this organization on rabbitto-rabbit
graft functional properties, isolating
the graft to avoid contamination of graft
responses by host retinal activity. Transient ON
or ON-OFF spike-like responses and local
electroretinograms (L-ERGs) were recorded
simultaneously via a single electrode on the graft
surface. These response components depended
on stimulus diameter, sometimes in a way indicating
antagonistic center-surround receptive
field organization and spatial tuning (43%).
Other times, the responses were an increasing
function of stimulus diameter which saturated
for large spots (57%). Response amplitudes were
transplantation surgery is to be done with
therapeutic aims
Adult-Acquired Flatfoot Deformity and Age-Related Differences in Foot and Ankle Kinematics During the Single-Limb Heel-Rise Test
STUDY DESIGN: Cross-sectional laboratory study.
OBJECTIVE: To compare single-limb heel-rise performance and foot-ankle kinematics between persons with stage 2 adult-acquired flatfoot deformity (AAFD) and healthy controls.
BACKGROUND: The inability to perform a single-limb heel rise is considered a positive functional diagnostic test for AAFD. However, which foot motions contribute to poor performance of this task are not known.
METHODS: Fifty individuals participated in this study, 20 with stage 2 AAFD (mean +/- SD age, 57.6 +/- 11.3 years), and 15 older participants (age, 56.8 +/- 5.3 years) and 15 younger participants (age, 22.2 +/- 2.4 years) without AAFD as control groups. Forefoot (sagittal plane) and rearfoot (sagittal and frontal planes) kinematics were collected using a 3-D motion analysis system. Heel-rise performance (heel height) and kinematics (joint angles, excursions) were evaluated. One-way and 2-way analyses of variance were used to examine differences in heel-rise performance and kinematics between groups.
RESULTS: Individuals with AAFD and older controls demonstrated lower heel-rise height than those in the younger control group (P\u3c.001). Persons with AAFD demonstrated higher degrees of first metatarsal dorsiflexion (P\u3c.001), lower ankle plantar flexion (P\u3c.001), and higher subtalar eversion (P = .027) than those in the older control group. Persons with AAFD demonstrated lower ankle excursion (P\u3c.001) and first metatarsal excursion (P\u3c.001) than those in the older control group, but no difference in subtalar excursion (P = .771).
CONCLUSION: Persons with stage 2 AAFD did not achieve sufficient heel height during a single-leg heel rise. Both forefoot and rearfoot kinematics in the sagittal plane, as opposed to the frontal plane, contributed to the lower heel height in participants with stage 2 AAFD. Older controls demonstrated lower heel-rise height than younger controls, indicating that clinical expectations of heel-rise performance may need to be adjusted for age
Ultrastructural Circuitry in Retinal Cell Transplants to Rat Retina
The development of five transplants of fetal
retinal tissue to adult rat eyes was examined
with the electron microscope. The transplants
were of 9 to 10 weeks total age after conception
in four cases and 20 weeks in one case. They
were at stage E15 when transplanted.
Transplants developed in both the epiretinal and
subretinal spaces
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