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<i>Sall4</i> regulates downstream patterning genes during limb regeneration
Many salamanders can completely regenerate a fully functional limb. Limb regeneration is a carefully coordinated process involving several defined stages. One key event during the regeneration process is the patterning of the blastema to inform cells of what they must differentiate into. Although it is known that many genes involved in the initial development of the limb are re-used during regeneration, the exact molecular circuitry involved in this process is not fully understood. Several large-scale transcriptional profiling studies of axolotl limb regeneration have identified many transcription factors that are up-regulated after limb amputation. Sall4 is a transcription factor that has been identified to play essential roles in maintaining cells in an undifferentiated state during development and also plays a unique role in limb development. Inactivation of Sall4 during limb bud development results in defects in anterior-posterior patterning of the limb. Sall4 has been found to be up-regulated during limb regeneration in both Xenopus and salamanders, but to date it function has been untested. We confirmed that Sall4 is up-regulated during limb regeneration in the axolotl using qRT-PCR and identified that it is present in the skin cells and also in cells within the blastema. Using CRISPR technology we microinjected gRNAs specific for Sall4 complexed with cas9 protein into the blastema to specifically knockout Sall4 in blastema cells only. This resulted in limb regenerate defects, including missing digits, fusion of digit elements, and defects in the radius and ulna. This suggests that during regeneration Sall4 may play a similar role in regulating the specification of anterior-proximal skeletal elements
Observing Exoplanets with High-Dispersion Coronagraphy. II. Demonstration of an Active Single-Mode Fiber Injection Unit
High-dispersion coronagraphy (HDC) optimally combines high contrast imaging
techniques such as adaptive optics/wavefront control plus coronagraphy to high
spectral resolution spectroscopy. HDC is a critical pathway towards fully
characterizing exoplanet atmospheres across a broad range of masses from giant
gaseous planets down to Earth-like planets. In addition to determining the
molecular composition of exoplanet atmospheres, HDC also enables Doppler
mapping of atmosphere inhomogeneities (temperature, clouds, wind), as well as
precise measurements of exoplanet rotational velocities. Here, we demonstrate
an innovative concept for injecting the directly-imaged planet light into a
single-mode fiber, linking a high-contrast adaptively-corrected coronagraph to
a high-resolution spectrograph (diffraction-limited or not). Our laboratory
demonstration includes three key milestones: close-to-theoretical injection
efficiency, accurate pointing and tracking, on-fiber coherent modulation and
speckle nulling of spurious starlight signal coupling into the fiber. Using the
extreme modal selectivity of single-mode fibers, we also demonstrated speckle
suppression gains that outperform conventional image-based speckle nulling by
at least two orders of magnitude.Comment: 10 pages, 7 figures, accepted by Ap
Keck Planet Imager and Characterizer (KPIC): status update
Here we report on the status of the The Keck Planet Imager and Characterizer (KPIC), which is an on-going series of upgrades to the W.M. Keck II adaptive optics system and instrument suite focused on exoplanet imaging and spectroscopic characterization. The KPIC infrared pyramid wavefront sensor and fiber injection unit to high-resolution infrared spectrograph NIRSPEC have been assembled, integrated and are under-going tests at the University of Hawaii before installation at the Summit in the Fall of 2018
First version of the fiber injection unit for the Keck Planet Imager and Characterizer
Coupling a high-contrast imaging instrument to a high-resolution spectrograph has the potential to enable the most detailed characterization of exoplanet atmospheres, including spin measurements and Doppler mapping. The high-contrast imaging system serves as a spatial filter to separate the light from the star and the planet while the high-resolution spectrograph acts as a spectral filter, which differentiates between features in the stellar and planetary spectra. The Keck Planet Imager and Characterizer (KPIC) located downstream from the current W. M. Keck II adaptive optics (AO) system will contain a fiber injection unit (FIU) combining a high-contrast imaging system and a fiber feed to Keck’s high resolution infrared spectrograph NIRSPEC. Resolved thermal emission from known young giant exoplanets will be injected into a single-mode fiber linked to NIRSPEC, thereby allowing the spectral characterization of their atmospheres. Moreover, the resolution of NIRSPEC (R = 37,500 after upgrade) is high enough to enable spin measurements and Doppler imaging of atmospheric weather phenomenon. The module was integrated at Caltech and shipped to Hawaii at the beginning of 2018 and is currently undergoing characterization. Its transfer to Keck is planned in September and first on-sky tests sometime in December
American College of Clinical Pharmacy White Paper: Cultural Competency in Health Care and Its Implications for Pharmacy Part 3A: Emphasis on Pharmacy Education, Curriculums, and Future Directions
Culture influences patients\u27 beliefs and behaviors toward health and illness. As the U.S. population becomes more diverse, a critical need exists for pharmacy education to incorporate patient-centered culturally sensitive health care knowledge and skills into the curriculum. Nursing was the first profession to incorporate this type of learning and training into its curriculums, followed by medicine. Pharmacy has also made great progress to revise curriculums, but inconsistency exists in depth, breadth, and methods across pharmacy colleges. This article addresses important aspects of pharmacy education such as curriculum development, incorporation of educational innovations and techniques into the teaching of patient-centered culturally sensitive health care across the curriculum from didactic to experiential learning, assessment tools, and global education. A preliminary model curriculum with objectives and examples of teaching methods is proposed. Future directions in pharmacy education, teaching and learning scholarship, postgraduate education, licensure, and continuing education are also presented
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