125 research outputs found

    Two are better than one: Fundamental parameters of frame coherence

    Full text link
    This paper investigates two parameters that measure the coherence of a frame: worst-case and average coherence. We first use worst-case and average coherence to derive near-optimal probabilistic guarantees on both sparse signal detection and reconstruction in the presence of noise. Next, we provide a catalog of nearly tight frames with small worst-case and average coherence. Later, we find a new lower bound on worst-case coherence; we compare it to the Welch bound and use it to interpret recently reported signal reconstruction results. Finally, we give an algorithm that transforms frames in a way that decreases average coherence without changing the spectral norm or worst-case coherence

    Restricted Isometries for Partial Random Circulant Matrices

    Get PDF
    In the theory of compressed sensing, restricted isometry analysis has become a standard tool for studying how efficiently a measurement matrix acquires information about sparse and compressible signals. Many recovery algorithms are known to succeed when the restricted isometry constants of the sampling matrix are small. Many potential applications of compressed sensing involve a data-acquisition process that proceeds by convolution with a random pulse followed by (nonrandom) subsampling. At present, the theoretical analysis of this measurement technique is lacking. This paper demonstrates that the ssth order restricted isometry constant is small when the number mm of samples satisfies m(slogn)3/2m \gtrsim (s \log n)^{3/2}, where nn is the length of the pulse. This bound improves on previous estimates, which exhibit quadratic scaling

    Fertility preservation for male patients with childhood, adolescent, and young adult cancer:recommendations from the PanCareLIFE Consortium and the International Late Effects of Childhood Cancer Guideline Harmonization Group

    Get PDF
    Item does not contain fulltextMale patients with childhood, adolescent, and young adult cancer are at an increased risk for infertility if their treatment adversely affects reproductive organ function. Future fertility is a primary concern of patients and their families. Variations in clinical practice are barriers to the timely implementation of interventions that preserve fertility. As part of the PanCareLIFE Consortium, in collaboration with the International Late Effects of Childhood Cancer Guideline Harmonization Group, we reviewed the current literature and developed a clinical practice guideline for fertility preservation in male patients who are diagnosed with childhood, adolescent, and young adult cancer at age 25 years or younger, including guidance on risk assessment and available methods for fertility preservation. The Grading of Recommendations Assessment, Development and Evaluation methodology was used to grade the available evidence and to form the recommendations. Recognising the need for global consensus, this clinical practice guideline used existing evidence and international expertise to rigorously develop transparent recommendations that are easy to use to facilitate the care of male patients with childhood, adolescent, and young adult cancer who are at high risk of fertility impairment and to enhance their quality of life

    The PTEN and INK4A/ARF tumor suppressors maintain myelolymphoid homeostasis and cooperate to constrain histiocytic sarcoma development in humans.

    Get PDF
    Histiocytic sarcoma (HS) is a rare malignant proliferation of histiocytes of uncertain molecular pathogenesis. Here, genetic analysis of coincident loss of Pten and Ink4a/Arf tumor suppressors in the mouse revealed a neoplastic phenotype dominated by a premalignant expansion of biphenotypic myelolymphoid cells followed by the development of HS. Pten protein loss occurred only in the histiocytic portion of tumors, suggesting a stepwise genetic inactivation in the generation of HS. Similarly, human HS showed genetic or epigenetic inactivation of PTEN, p16(INK4A), and p14(ARF), supporting the relevance of this genetically engineered mouse model of HS. These genetic and translational observations establish a cooperative role of Pten and Ink4a/Arf in the development of HS and provide mechanistic insights into the pathogenesis of human HS

    Zu Werther

    No full text
    corecore