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HNRNPK maintains epidermal progenitor function through transcription of proliferation genes and degrading differentiation promoting mRNAs.
Maintenance of high-turnover tissues such as the epidermis requires a balance between stem cell proliferation and differentiation. The molecular mechanisms governing this process are an area of investigation. Here we show that HNRNPK, a multifunctional protein, is necessary to prevent premature differentiation and sustains the proliferative capacity of epidermal stem and progenitor cells. To prevent premature differentiation of progenitor cells, HNRNPK is necessary for DDX6 to bind a subset of mRNAs that code for transcription factors that promote differentiation. Upon binding, these mRNAs such as GRHL3, KLF4, and ZNF750 are degraded through the mRNA degradation pathway, which prevents premature differentiation. To sustain the proliferative capacity of the epidermis, HNRNPK is necessary for RNA Polymerase II binding to proliferation/self-renewal genes such as MYC, CYR61, FGFBP1, EGFR, and cyclins to promote their expression. Our study establishes a prominent role for HNRNPK in maintaining adult tissue self-renewal through both transcriptional and post-transcriptional mechanisms
Influence of media coverage and sentiment on seasoned equity offerings.
This article examines the role of media in seasoned equity offerings (SEOs) price and market reactions on SEO announcements. Using a sample of SEO deals in UK, we find that media coverage is significantly and negatively related to SEO price discounts and market returns around SEO announcements. Moreover, we document that more pessimistic media sentiment predicts larger SEO price discounts and more negative market reactions to SEO announcements. In summary, both media coverage and media sentiment influence investor decisions in SEOs, but through different mechanisms
CompRRAE: RRAM-based Convolutional Neural Network Accelerator with Reduced Computations through a Runtime Activation Estimation
Recently Resistive-RAM (RRAM) crossbar has been used in the design of the
accelerator of convolutional neural networks (CNNs) to solve the memory wall
issue. However, the intensive multiply-accumulate computations (MACs) executed
at the crossbars during the inference phase are still the bottleneck for the
further improvement of energy efficiency and throughput. In this work, we
explore several methods to reduce the computations for the RRAM-based CNN
accelerators. First, the output sparsity resulting from the widely employed
Rectified Linear Unit is exploited, and a significant portion of computations
are bypassed through an early detection of the negative output activations.
Second, an adaptive approximation is proposed to terminate the MAC early when
the sum of the partial results of the remaining computations is considered to
be within a certain range of the intermediate accumulated result and thus has
an insignificant contribution to the inference. In order to determine these
redundant computations, a novel runtime estimation on the maximum and minimum
values of each output activation is developed and used during the MAC
operation. Experimental results show that around 70% of the computations can be
reduced during the inference with a negligible accuracy loss smaller than 0.2%.
As a result, the energy efficiency and the throughput are improved by over 2.9
and 2.8 times, respectively, compared with the state-of-the-art RRAM-based
accelerators.Comment: 7 pages, 6 figures, Accepted by ASP-DAC 201
Simulating the 1998 spring bloom in Lake Michigan using a coupled physical‐biological model
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95047/1/jgrc12526.pd
Polypyrrole/TiO2 nanotube arrays with coaxial heterogeneous structure as sulfur hosts for lithium sulfur batteries
The lithium-sulfur cell has shown great prospects for future energy conversion and storage systems due to the high theoretical specific capacity of sulfur, 1675 mAh g−1. However, it has been hindered by rapid capacity decay and low energy efficiency. In this work, polypyrrole (PPy)/TiO2 nanotubes with coaxial heterogeneous structure as the substrate of the cathode is prepared and used to improve the electrochemical performance of sulfur electrodes. TiO2 nanotubes decorated with PPy provide a highly ordered conductive framework for Li+ ion diffusion and reaction with sulfur. This architecture also is helpful for trapping the produced polysulfides, and as a result attenuates the capacity decay. Furthermore, the heat treatment temperature used in the sulfur loading process has been confirmed to have an important impact on the overall performance of the resultant cell. The as-designed S/PPy/TiO2 nanotube cathode using an elevated heating temperature shows excellent cycling stability with a high discharge capacity of 1150 mAh g−1 and average coulombic efficiency of 96% after 100 cycles
NRAV, a Long Noncoding RNA, Modulates Antiviral Responses through Suppression of Interferon-Stimulated Gene Transcription
SummaryLong noncoding RNAs (lncRNAs) modulate various biological processes, but their role in host antiviral responses is largely unknown. Here we identify a lncRNA as a key regulator of antiviral innate immunity. Following from the observation that a lncRNA that we call negative regulator of antiviral response (NRAV) was dramatically downregulated during infection with several viruses, we ectopically expressed NRAV in human cells or transgenic mice and found that it significantly promotes influenza A virus (IAV) replication and virulence. Conversely, silencing NRAV suppressed IAV replication and virus production, suggesting that reduction of NRAV is part of the host antiviral innate immune response to virus infection. NRAV negatively regulates the initial transcription of multiple critical interferon-stimulated genes (ISGs), including IFITM3 and MxA, by affecting histone modification of these genes. Our results provide evidence for a lncRNA in modulating the antiviral interferon response
Generalized Bergman kernels on symplectic manifolds
We study the near diagonal asymptotic expansion of the generalized Bergman
kernel of the renormalized Bochner-Laplacian on high tensor powers of a
positive line bundle over a compact symplectic manifold. We show how to compute
the coefficients of the expansion by recurrence and give a closed formula for
the first two of them. As consequence, we calculate the density of states
function of the Bochner-Laplacian and establish a symplectic version of the
convergence of the induced Fubini-Study metric. We also discuss generalizations
of the asymptotic expansion for non-compact or singular manifolds as well as
their applications. Our approach is inspired by the analytic localization
techniques of Bismut-Lebeau.Comment: 48 pages. Add two references on the Hermitian scalar curvatur
Design of a Multiband RF Slotted-Antenna for Biosensing Applications
There is an expanding demand for adaptive contactless label-free biosensors for point-of-care, multi-user, health risk-free applications. This paper introduces the design of an elliptically-slotted patch antenna (ESPA) for bio-sensing applications. The resonance frequency difference of the ESPA is 2.5% compared with the basic slot-less patch antenna of 6.6%. Hence, the proposed model compares with the conventional slot-less patch antenna and exhibited a vast improvement in its bandwidth efficiency by over 62%. The simulated ESPA design yields a total gain of 7.5 dBi and can be utilized for simultaneous bio-sample detection and signal transmission applications. The miniaturized size of this system promises a portable label-free, reliable, realtime detection with a cost-effective fabrication
The Infrared Imaging Spectrograph (IRIS) for TMT: Instrument Overview
We present an overview of the design of IRIS, an infrared (0.84 - 2.4 micron)
integral field spectrograph and imaging camera for the Thirty Meter Telescope
(TMT). With extremely low wavefront error (<30 nm) and on-board wavefront
sensors, IRIS will take advantage of the high angular resolution of the narrow
field infrared adaptive optics system (NFIRAOS) to dissect the sky at the
diffraction limit of the 30-meter aperture. With a primary spectral resolution
of 4000 and spatial sampling starting at 4 milliarcseconds, the instrument will
create an unparalleled ability to explore high redshift galaxies, the Galactic
center, star forming regions and virtually any astrophysical object. This paper
summarizes the entire design and basic capabilities. Among the design
innovations is the combination of lenslet and slicer integral field units, new
4Kx4k detectors, extremely precise atmospheric dispersion correction, infrared
wavefront sensors, and a very large vacuum cryogenic system.Comment: Proceedings of the SPIE, 9147-76 (2014
Functional Role of Cyclin-Dependent Kinase 5 in the Regulation of Melanogenesis and Epidermal Structure
The mammalian integumentary system plays important roles in body homeostasis, and dysfunction of melanogenesis or epidermal development may lead to a variety of skin diseases, including melanoma. Skin pigmentation in humans and coat color in fleece-producing animals are regulated by many genes. Among them, microphthalmia-associated transcription factor (MITF) and paired-box 3 (PAX3) are at the top of the cascade and regulate activities of many important melanogenic enzymes. Here, we report for the first time that cyclin-dependent kinase 5 (Cdk5) is an essential regulator of MITF and PAX3. Cdk5 knockdown in mice causes a lightened coat color, a polarized distribution of melanin and hyperproliferation of basal keratinocytes. Reduced expression of Keratin 10 (K10) resulting from Cdk5knockdown may be responsible for an abnormal epidermal structure. In contrast, overexpression of Cdk5 in sheep (Ovis aries) only produces brown patches on a white background, with no other observable abnormalities. Collectively, our findings show that Cdk5 has an important functional role in the regulation of melanin production and transportation and in normal development of the integumentary system
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