The rockefeller university

Tornadoes cause loss of life and damage to property each year in the United States and around the world. The largest impacts come from 'outbreaks' consisting of multiple tornadoes closely spaced in time. Here we find an upward trend in the annual mean number of tornadoes per US tornado outbreak for the period 1954-2014. Moreover, the variance of this quantity is increasing more than four times as fast as the mean. The mean and variance of the number of tornadoes per outbreak vary according to Taylor's power law of fluctuation scaling (TL), with parameters that are consistent with multiplicative growth. Tornado-related atmospheric proxies show similar power-law scaling and multiplicative growth. Path-length-integrated tornado outbreak intensity also follows TL, but with parameters consistent with sampling variability. The observed TL power-law scaling of outbreak severity means that extreme outbreaks are more frequent than would be expected if mean and variance were independent or linearly related.

TGF-beta signaling can be pro-tumorigenic or tumor suppressive. We investigated this duality in pancreatic ductal adenocarcinoma (PDA), which, with other gastrointestinal cancers, exhibits frequent inactivation of the TGF-beta mediator Smad4. We show that TGF-beta induces an epithelial-mesenchymal transition (EMT), generally considered a pro-tumorigenic event. However, in TGF-beta-sensitive PDA cells, EMT becomes lethal by converting TGF-beta-induced Sox4 from an enforcer of tumorigenesis into a promoter of apoptosis. This is the result of an EMT-linked remodeling of the cellular transcription factor landscape, including the repression of the gastrointestinal lineage-master regulator Klf5. Klf5 cooperates with Sox4 in oncogenesis and prevents Sox4-induced apoptosis. Smad4 is required for EMT but dispensable for Sox4 induction by TGF-beta. TGF-beta-induced Sox4 is thus geared to bolster progenitor identity, whereas simultaneous Smad4-dependent EMT strips Sox4 of an essential partner in oncogenesis. Our work demonstrates that TGF-beta tumor suppression functions through an EMT-mediated disruption of a lineage-specific transcriptional network.

The Chlamydomonas genome has been sequenced, assembled, and annotated to produce a rich resource for genetics and molecular biology in this well-studied model organism. The annotated genome is very rich in open reading frames upstream of the annotated coding sequence ('uORFs'): almost three quarters of the assigned transcripts have at least one uORF, and frequently more than one. This is problematic with respect to the standard 'scanning' model for eukaryotic translation initiation. These uORFs can be grouped into three classes: class 1, initiating in-frame with the coding sequence (CDS) (thus providing a potential in-frame N-terminal extension); class 2, initiating in the 59 untranslated sequences (5UT) and terminating out-of-frame in the CDS; and class 3, initiating and terminating within the 5UT. Multiple bioinformatics criteria (including analysis of Kozak consensus sequence agreement and BLASTP comparisons to the closely related Volvox genome, and statistical comparison to cds and to random sequence controls) indicate that of similar to 4000 class 1 uORFs, approximately half are likely in vivo translation initiation sites. The proposed resulting N-terminal extensions in many cases will sharply alter the predicted biochemical properties of the encoded proteins. These results suggest significant modifications in similar to 2000 of the similar to 20,000 transcript models with respect to translation initiation and encoded peptides. In contrast, class 2 uORFs may be subject to purifying selection, and the existent ones (surviving selection) are likely inefficiently translated. Class 3 uORFs are found in more than half of transcripts, frequently multiple times per transcript; however, they are remarkably similar to random sequence expectations with respect to size, number, and composition, and therefore may in most cases be selectively neutral.

The angular distributions and the differential branching fraction of the decay B-0 -> K*(892)(0)mu(+)mu(-) are studied using data corresponding to an integrated luminosity of 20.5 fb(-1) collected with the CMS detector at the LHC in pp collisions at root s = 8 TeV. From 1430 signal decays, the forward-backward asymmetry of the muons, the K*(892)(0) longitudinal polarization fraction, and the differential branching fraction are determined as a function of the dimuon invariant mass squared. The measurements are among the most precise to date and are in good agreement with standard model predictions. (C) 2015 CERN for the benefit of the CMS Collaboration. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

Stem cell technology can allow us to produce human neuronal cell types outside the body, but what exactly are stem cells, and what challenges are associated with their use? Stem cells are a kind of cell that has the capacity to self-renew to produce additional stem cells by mitosis, and also to differentiate into other-more mature-cell types. Stem cells are usually categorized as multipotent (able to give rise to multiple cells within a lineage), pluripotent (able to give rise to all cell types in an adult) and totipotent (able to give rise to all embryonic and adult lineages). Multipotent adult stem cells are found throughout the body, and they include neural stem cells. The challenge in utilizing adult stem cells for disease research is obtaining cells that are genetically matched to people with disease phenotypes, and being able to differentiate them into the appropriate cell types of interest. As adult neural stem cells reside in the brain, their isolation would require considerably invasive and dangerous procedures. In contrast, pluripotent stem cells are easy to obtain, due to the paradigm-shifting work on direct reprogramming of human skin fibroblasts into induced pluripotent stem cells. This work has enabled us to produce neurons that are genetically matched to individual patients. While we are able to isolate pluripotent stem cells from patients in a minimally invasive manner, we do not yet fully understand how to direct these cells to many of the medically important neuroendocrine fates. Progress in this direction continues to be made, on multiple fronts, and it involves using small molecules and proteins to mimic developmentally important signals, as well as building on advances in "reprogramming" to directly convert one cell type into another by forced expression of sets of transcription factors. An additional challenge involves providing these cells with the appropriate environment to induce their normal behavior outside the body. Despite these challenges, the promise of producing human neuroendocrine cell types in vitro gives opportunities for unique insights and is therefore worthwhile.

Electrophysiology has recently evolved into an interactive, high-throughput endeavor. Recording from dozens to hundreds of electrodes is today routine; novel means of manipulating the system in real time, through electrical stimulation, optogenetics or sensory manipulation are allowing us to decipher neural circuit function at an unparalleled rate. To contribute to the wide dissemination of such techniques, we present an open hardware project, High-Channel Count Electrophysiology (HiCCE), aiming to produce low-cost, high-channel count (>= 128 channels) electrophysiology instrumentation capable of fast data acquisition rates, real-time processing and feedback capabilities. Our design is centered on an open standard, FPGA Mezzanine Card (FMC), which permits a varied choice of FPGA carrier architectures suited to different laboratory experimental needs. The HiCCE-128, a low-cost high-performance 128-channel data acquisition board for small voltage signals, is being introduced. It is a FMC module that can be operated from any FPGA carrier conforming to the FMC/VITA57 standard. This specialized board with a low input referred noise of about 3 mu V is capable of acquiring 128 channels simultaneously at 31.25 kS/s per channel with 16 effective bits of resolution. We present the global architecture and some preliminary measurement to illustrate its potential for electrophysiological and medical applications.