BACKGROUND Crumbs (Crb), a cell polarity gene, has been shown to provide a positional cue for the apical membrane domain and adherens junction during Drosophila photoreceptor morphogenesis. It has recently been found that stable microtubules in developing Drosophila photoreceptors were linked to Crb localization. Coordinated interactions between microtubule and actin cytoskeletons are involved ...

Drosophila melanogaster Crumbs (Crb) and its mammalian orthologues (CRB1-3) share evolutionarily conserved but poorly defined roles in regulating epithelial polarity and, in photoreceptor cells, morphogenesis and stability. Elucidating the molecular mechanisms of Crb function is vital, as mutations in the human CRB1 gene cause retinal dystrophies. Here, we report that Crb restricts Rac1-NADPH o...

The problem considered in this letter is to bound the performance of estimators of a deterministic parameter which satisfies given constraints. Specifically, previous work on the constrained Cramér–Rao bound (CRB) is generalized to include singular Fisher information matrices and biased estimators. A necessary and sufficient condition for the existence of a finite CRB is obtained. A closed form...

In this paper, the problem of carrier frequency offset estimation for frequency-selective channels in a data-aided context is considered. The channel is assumed to be contaminated with an unknown noise and the Cramér-Rao bound (CRB) is used as an estimation accuracy criterion. The minimax approach consists in minimizing the worst-case (maximum) CRB of the frequency offset. Under certain assumpt...

A recent paper by Yang et al. [1] proposed CRBRPL as a new RPL-based routing protocol for communications in cognitive radio (CR) enabled smart grid. Essentially, CRB-RPL adopts the operation of CRB-MAC, which is a medium access control (MAC) protocol for cognitive machine-to-machine (M2M) communications, and depicts it as a network layer enhancement. CRB-RPL suffers from a number of technical f...

Regulation of epithelial tube size is critical for organ function. However, the mechanisms of tube size control remain poorly understood. In the Drosophila trachea, tube dimensions are regulated by a luminal extracellular matrix (ECM). ECM organization requires apical (luminal) secretion of the protein Vermiform (Verm), which depends on the basolateral septate junction (SJ). Here, we show that ...

A Cramér-Rao bound (CRB) for semi-blind channel estimators in redundant block transmission systems is derived. The derived CRB is valid for any system adopting a full-rank linear redundant precoder, including the popular cyclicprefixed orthogonal frequency-division multiplexing system. Simple forms of CRBs for multiple complex parameters, either unconstrained or constrained by a holomorphic fun...

Wilms tumor (WT) is the most common pediatric malignant primary renal tumor. Carboplatin (CRB), a platinum compound is widely used in the treatment of multiple cancers including ovarian, lung, head and neck, and wilm's tumor. However, lower uptake of CRB in cancer cells and toxicity concerns in healthy cells often limited its clinical outcome. The aim of this study was to investigate the antitu...

Epithelial tissues are composed of polarized cells with distinct apical and basolateral membrane domains. In the Drosophila ovarian follicle cell epithelium, apical membranes are specified by Crumbs (Crb), Stardust (Sdt), and the aPKC-Par6-cdc42 complex. Basolateral membranes are specified by Lethal giant larvae (Lgl), Discs large (Dlg), and Scribble (Scrib). Apical and basolateral determinants...

Alzheimer's disease (AD, OMIM: 104300), a progressive neurodegenerative disorder with no cure to date, is caused by the generation of amyloid-beta-42 (Aβ42) aggregates that trigger neuronal cell death by unknown mechanism(s). We have developed a transgenic Drosophila eye model where misexpression of human Aβ42 results in AD-like neuropathology in the neural retina. We have identified an apical-...