124 research outputs found
A Phenomenological Study of Co-Teaching\u27s Collaborative Decision Making Process in Taiwanese Elementary School
Considering the prevalence of the co-teaching model in Taiwan, there is little research describing the partnership\u27s decision-making process. This study uses the phenomenological methodology to better understand their lived experience making choices as a team. This project proposes the research question: How do co-teachers make decisions together in the classroom? Semi-structured interviews were conducted with two co-teaching partnerships in Taiwan English education elementary classroom. In this project, the five themes described are shared responsibility, team planning or lack thereof it, dynamic and expectation of roles, beliefs about classroom management and education, differences of belief and background, and unanticipated outcomes and vague disillusionment. Using the theoretical framework of Varghese, Morgan, Johnston, and Johnson (2005) particularly Language Teacher Identity, and Wegner, (1998) Dimensions of practice as the properties of the community allows for an understanding of the co-teaching decision making process for members in Taiwan elementary school. Analyzing the co-teachers’ decision making in terms of co-teacher identity conflict, discourse socialization and negotiation provides necessary insight. Recommendations involve research for pre-service teachers involving Language Teacher Identity, but specifically with the growing numbers of foreign teachers arriving to Taiwan. The foreign teachers that are coming to teach in Taiwan need available information, and resources pertaining to discourse socialization, and agency in teacher identity. Further research is needed in regards to Language Teacher Identity conflict, agency, and negotiation, as it is an under-researched field for co-teachers to better understand and communicate about these issues. Additionally local education bureaus need to be more effective in dealing with inappropriate designations for foreign teachers in Taiwan with the local private school franchises
Culture of equine fibroblast-like synoviocytes on synthetic tissue scaffolds towards meniscal tissue engineering: a preliminary cell-seeding study
Introduction. Tissue engineering is a new methodology for addressing meniscal injury or loss. Synovium may be an ideal source of cells for in vitro meniscal fibrocartilage formation, however, favorable in vitro culture conditions for synovium must be established in order to achieve this goal. The objective of this study was to determine cellularity, cell distribution, and extracellular matrix (ECM) formation of equine fibroblast-like synoviocytes (FLS) cultured on synthetic scaffolds, for potential application in synovium-based meniscal tissue engineering. Scaffolds included open-cell poly-L-lactic acid (OPLA) sponges and polyglycolic acid (PGA) scaffolds cultured in static and dynamic culture conditions, and PGA scaffolds coated in poly-L-lactic (PLLA) in dynamic culture conditions.Materials and Methods. Equine FLS were seeded on OPLA and PGA scaffolds, and cultured in a static environment or in a rotating bioreactor for 12 days. Equine FLS were also seeded on PGA scaffolds coated in 2% or 4% PLLA and cultured in a rotating bioreactor for 14 and 21 days. Three scaffolds from each group were fixed, sectioned and stained with Masson’s Trichrome, Safranin-O, and Hematoxylin and Eosin, and cell numbers and distribution were analyzed using computer image analysis. Three PGA and OPLA scaffolds from each culture condition were also analyzed for extracellular matrix (ECM) production via dimethylmethylene blue (sulfated glycosaminoglycan) assay and hydroxyproline (collagen) assay. PLLA coated PGA scaffolds were analyzed using double stranded DNA quantification as areflection of cellularity and confocal laser microscopy in a fluorescent cell viability assay.Results. The highest cellularity occurred in PGA constructs cultured in a rotating bioreactor, which also had a mean sulfated glycosaminoglycan content of 22.3 µg per scaffold. PGA constructs cultured in static conditions had the lowest cellularity. Cells had difficulty adhering to OPLA and the PLLA coating of PGA scaffolds; cellularity was inversely proportional to the concentration of PLLA used. PLLA coating did not prevent dissolution of the PGA scaffolds. All cell scaffold types and culture conditions produced non-uniform cellular distribution.Discussion/Conclusion. FLS-seeding of PGA scaffolds cultured in a rotating bioreactor resulted in the most optimal cell and matrix characteristics seen in this study. Cells grew only in the pores of the OPLA sponge, and could not adhere to the PLLA coating of PGA scaffold, due to the hydrophobic property of PLA. While PGA culture in a bioreactor produced measureable GAG, no culture technique produced visible collagen. For this reason, and due to the dissolution of PGA scaffolds, the culture conditions and scaffolds described here are not recommended for inducing fibrochondrogenesis in equine FLS for meniscal tissue engineering
Probing the Interiors of Very Hot Jupiters Using Transit Light Curves
Accurately understanding the interior structure of extra-solar planets is
critical for inferring their formation and evolution. The internal density
distribution of a planet has a direct effect on the star-planet orbit through
the gravitational quadrupole field created by the rotational and tidal bulges.
These quadrupoles induce apsidal precession that is proportional to the
planetary Love number (, twice the apsidal motion constant), a bulk
physical characteristic of the planet that depends on the internal density
distribution, including the presence or absence of a massive solid core. We
find that the quadrupole of the planetary tidal bulge is the dominant source of
apsidal precession for very hot Jupiters ( AU), exceeding the
effects of general relativity and the stellar quadrupole by more than an order
of magnitude. For the shortest-period planets, the planetary interior induces
precession of a few degrees per year. By investigating the full photometric
signal of apsidal precession, we find that changes in transit shapes are much
more important than transit timing variations. With its long baseline of
ultra-precise photometry, the space-based \emph{Kepler} mission can
realistically detect apsidal precession with the accuracy necessary to infer
the presence or absence of a massive core in very hot Jupiters with orbital
eccentricities as low as . The signal due to creates
unique transit light curve variations that are generally not degenerate with
other parameters or phenomena. We discuss the plausibility of measuring
in an effort to directly constrain the interior properties of
extra-solar planets.Comment: updated, improved, and expanded manuscript has been accepted by the
Astrophysical Journal; 19 pages, 7 figure
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Culture of equine fibroblast-like synoviocytes on synthetic tissue scaffolds towards meniscal tissue engineering: a preliminary cell-seeding study
INTRODUCTION: Tissue engineering is a new methodology for addressing meniscal
injury or loss. Synovium may be an ideal source of cells for in vitro meniscal fibrocartilage
formation, however, favorable in vitro culture conditions for synovium must be
established in order to achieve this goal. The objective of this study was to determine
cellularity, cell distribution, and extracellular matrix (ECM) formation of equine
fibroblast-like synoviocytes (FLS) cultured on synthetic scaffolds, for potential application
in synovium-based meniscal tissue engineering. Scaffolds included open-cell
poly-L-lactic acid (OPLA) sponges and polyglycolic acid (PGA) scaffolds cultured
in static and dynamic culture conditions, and PGA scaffolds coated in poly-L-lactic
(PLLA) in dynamic culture conditions.
MATERIALS AND METHODS: Equine FLS were seeded on OPLA and PGA scaffolds, and
cultured in a static environment or in a rotating bioreactor for 12 days. Equine FLS
were also seeded on PGA scaffolds coated in 2% or 4% PLLA and cultured in a
rotating bioreactor for 14 and 21 days. Three scaffolds from each group were fixed,
sectioned and stained with Masson’s Trichrome, Safranin-O, and Hematoxylin and
Eosin, and cell numbers and distribution were analyzed using computer image analysis.
Three PGA and OPLA scaffolds from each culture condition were also analyzed
for extracellular matrix (ECM) production via dimethylmethylene blue (sulfated
glycosaminoglycan) assay and hydroxyproline (collagen) assay. PLLA coated PGA
scaffolds were analyzed using double stranded DNA quantification as a reflection of
cellularity and confocal laser microscopy in a fluorescent cell viability assay.
RESULTS: The highest cellularity occurred in PGA constructs cultured in a rotating
bioreactor, which also had a mean sulfated glycosaminoglycan content of 22.3 μg per
scaffold. PGA constructs cultured in static conditions had the lowest cellularity. Cells
had difficulty adhering to OPLA and the PLLA coating of PGA scaffolds; cellularity
was inversely proportional to the concentration of PLLA used. PLLA coating did not
prevent dissolution of the PGA scaffolds. All cell scaffold types and culture conditions
produced non-uniformcellular distribution. DISCUSSION/CONCLUSION: FLS-seeding of PGA scaffolds cultured in a rotating bioreactor resulted in the most optimal cell and matrix characteristics seen in this study.
Cells grew only in the pores of the OPLA sponge, and could not adhere to the PLLA
coating of PGA scaffold, due to the hydrophobic property of PLA. While PGA culture
in a bioreactor produced measureable GAG, no culture technique produced
visible collagen. For this reason, and due to the dissolution of PGA scaffolds, the
culture conditions and scaffolds described here are not recommended for inducing
fibrochondrogenesis in equine FLS for meniscal tissue engineering.Keywords: Stifle,
Orthopedics,
Bioreactors,
Fibroblast-like synoviocytes,
Meniscus,
Cell scaffolds,
Tissue engineering,
Bioengineering,
Veterinary Medicine,
Surgery and Surgical Specialties,
EquineThis is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by PeerJ. The published article can be found at: https://peerj.com/
Clec16a is critical for autolysosome function and Purkinje cell survival
CLEC16A is in a locus genetically linked to autoimmune diseases including multiple sclerosis, but the function of this gene in the nervous system is unknown. Here we show that two mouse strains carrying independent Clec16a mutations developed neurodegenerative disease characterized by motor impairments and loss of Purkinje cells. Neurons from Clec16a-mutant mice exhibited increased expression of the autophagy substrate p62, accumulation of abnormal intra-axonal membranous structures bearing the autophagy protein LC3, and abnormal Golgi morphology. Multiple aspects of endocytosis, lysosome and Golgi function were normal in Clec16a-deficient murine embryonic fibroblasts and HeLa cells. However, these cells displayed abnormal bulk autophagy despite unimpaired autophagosome formation. Cultured Clec16a-deficient cells exhibited a striking accumulation of LC3 and LAMP-1 positive autolysosomes containing undigested cytoplasmic contents. Therefore Clec16a, an autophagy protein that is critical for autolysosome function and clearance, is required for Purkinje cell survival
SARS-CoV-2 infection in central North Carolina: Protocol for a population-based longitudinal cohort study and preliminary participant results
Public health surveillance systems likely underestimate the true prevalence and incidence of SARS-CoV-2 infection due to limited access to testing and the high proportion of subclinical infections in community-based settings. This ongoing prospective, observational study aimed to generate accurate estimates of the prevalence and incidence of, and risk factors for, SARS-CoV-2 infection among residents of a central North Carolina county. From this cohort, we collected survey data and nasal swabs every two weeks and venous blood specimens every month. Nasal swabs were tested for the presence of SARS-CoV-2 virus (evidence of active infection), and serum specimens for SARS-CoV-2-specific antibodies (evidence of prior infection). As of June 23, 2021, we have enrolled a total of 153 participants from a county with an estimated 76,285 total residents. The anticipated study duration is at least 24 months, pending the evolution of the pandemic. Study data are being shared on a monthly basis with North Carolina state health authorities and future analyses aim to compare study data to state-wide metrics over time. Overall, the use of a probability-based sampling design and a well-characterized cohort will enable collection of critical data that can be used in planning and policy decisions for North Carolina and may be informative for other states with similar demographic characteristics
The development of HISPEC for Keck and MODHIS for TMT: science cases and predicted sensitivities
HISPEC is a new, high-resolution near-infrared spectrograph being designed
for the W.M. Keck II telescope. By offering single-shot, R=100,000 between 0.98
- 2.5 um, HISPEC will enable spectroscopy of transiting and non-transiting
exoplanets in close orbits, direct high-contrast detection and spectroscopy of
spatially separated substellar companions, and exoplanet dynamical mass and
orbit measurements using precision radial velocity monitoring calibrated with a
suite of state-of-the-art absolute and relative wavelength references. MODHIS
is the counterpart to HISPEC for the Thirty Meter Telescope and is being
developed in parallel with similar scientific goals. In this proceeding, we
provide a brief overview of the current design of both instruments, and the
requirements for the two spectrographs as guided by the scientific goals for
each. We then outline the current science case for HISPEC and MODHIS, with
focuses on the science enabled for exoplanet discovery and characterization. We
also provide updated sensitivity curves for both instruments, in terms of both
signal-to-noise ratio and predicted radial velocity precision.Comment: 25 pages, 9 figures. To appear in the Proceedings of SPIE: Techniques
and Instrumentation for Detection of Exoplanets XI, vol. 12680 (2023
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An extreme-mass ratio, short-period eclipsing binary consisting of a B dwarf primary and a pre-main-sequence M star companion discovered by KELT
We present the discovery of KELT J072709 + 072007 (HD 58730), a very low mass ratio (q ≡ M2/M1 ≈ 0.07) eclipsing binary (EB) identified by the Kilodegree Extremely Little Telescope (KELT) survey. We present the discovery light curve and perform a global analysis of four high-precision ground-based light curves, the Transiting Exoplanets Survey Satellite (TESS) light curve, radial velocity (RV) measurements, Doppler Tomography (DT) measurements, and the broad-band spectral energy distribution. Results from the global analysis are consistent with a fully convective (M2 = 0.22 ± 0.02 M☉) M star transiting a late-B primary (M1 = 3.34+−000709 M☉ and Teff,1 = 11960+−430520 K). We infer that the primary star is 183+−3330 Myr old and that the companion star's radius is inflated by 26 ± 8 per cent relative to the predicted value from a low-mass isochrone of similar age. We separately and analytically fit for the variability in the out-of-eclipse TESS phase curve, finding good agreement between the resulting stellar parameters and those from the global fit. Such systems are valuable for testing theories of binary star formation and understanding how the environment of a star in a close-but-detached binary affects its physical properties. In particular, we examine how a star's properties in such a binary might differ from the properties it would have in isolation
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