Consistent Right-Invariant Fixed-Lag Smoother with Application to Visual Inertial SLAM

State estimation problems without absolute position measurements routinely arise in navigation of unmanned aerial vehicles, autonomous ground vehicles, etc., whose proper operation relies on accurate state estimates and reliable covariances. Unaware of absolute positions, these problems have immanent unobservable directions. Traditional causal estimators, however, usually gain spurious information on the unobservable directions, leading to over-confident covariance inconsistent with actual estimator errors. The consistency problem of fixed-lag smoothers (FLSs) has only been attacked by the first estimate Jacobian (FEJ) technique because of the complexity to analyze their observability property. But the FEJ has several drawbacks hampering its wide adoption. To ensure the consistency of a FLS, this paper introduces the right invariant error formulation into the FLS framework. To our knowledge, we are the first to analyze the observability of a FLS with the right invariant error. Our main contributions are twofold. As the first novelty, to bypass the complexity of analysis with the classic observability matrix, we show that observability analysis of FLSs can be done equivalently on the linearized system. Second, we prove that the inconsistency issue in the traditional FLS can be elegantly solved by the right invariant error formulation without artificially correcting Jacobians. By applying the proposed FLS to the monocular visual inertial simultaneous localization and mapping (SLAM) problem, we confirm that the method consistently estimates covariance similarly to a batch smoother in simulation and that our method achieved comparable accuracy as traditional FLSs on real data.Comment: 13 pages, 4 figures, AAAI 2021 Conferenc

Muscle atrophy in transgenic mice expressing a human TSC1 transgene

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/116374/1/feb2s0014579306010866.pd

Ras promotes cell survival by antagonizing both JNK and Hid signals in the Drosophila eye

<p>Abstract</p> <p>Background</p> <p>Programmed cell death, or apoptosis, is a fundamental physiological process during normal development or in pathological conditions. The activation of apoptosis can be elicited by numerous signalling pathways. Ras is known to mediate anti-apoptotic signals by inhibiting Hid activity in the <it>Drosophila </it>eye. Here we report the isolation of a new loss-of-function <it>ras </it>allele, <it>ras</it>^<it>KP</it>, which causes excessive apoptosis in the <it>Drosophila </it>eye.</p> <p>Results</p> <p>This new function is likely to be mediated through the JNK pathway since the inhibition of JNK signalling can significantly suppress <it>ras</it>^<it>KP</it>-induced apoptosis, whereas the removal of <it>hid </it>only weakly suppresses the phenotype. Furthermore, the reduction of JNK signalling together with the expression of the baculovirus caspase inhibitor p35, which blocks Hid activity, strongly suppresses the <it>ras</it>^{<it>KP </it>}cell death. In addition, we find a strong correlation between <it>ras</it>^<it>KP</it>-induced apoptosis in the eye disc and the activation of JNK signalling.</p> <p>Conclusion</p> <p>In the <it>Drosophila </it>eye, Ras may protect cells from apoptosis by inhibiting both JNK and Hid activities. Surprisingly, reducing Ras activity in the wing, however, does not cause apoptosis but rather affects cell and organ size. Thus, in addition to its requirement for cell viability, Ras appears to mediate different biological roles depending on the developmental context and on the level of its expression.</p

Efficient Transposition of the piggyBac (PB) Transposon in Mammalian Cells and Mice

SummaryTransposable elements have been routinely used for genetic manipulation in lower organisms, including generating transgenic animals and insertional mutagenesis. In contrast, the usage of transposons in mice and other vertebrate systems is still limited due to the lack of an efficient transposition system. We have tested the ability of piggyBac (PB), a DNA transposon from the cabbage looper moth Trichoplusia ni, to transpose in mammalian systems. We show that PB elements carrying multiple genes can efficiently transpose in human and mouse cell lines and also in mice. PB permits the expression of the marker genes it carried. During germline transposition, PB could excise precisely from original insertion sites and transpose into the mouse genome at diverse locations, preferably transcription units. These data provide a first and critical step toward a highly efficient transposon system for a variety of genetic manipulations including transgenesis and insertional mutagenesis in mice and other vertebrates

Oxycodone vs. sufentanil combined with quadratus lumborum block vs. transverse abdominis plane block in laparoscopic major gastrointestinal surgery: A randomized factorial trial protocol

Background: Multimodal analgesia plays a key role in enhanced recovery after surgery. Herein, we describe a trial protocol investigating the effects of oxycodone-vs. sufentanil-based patient-controlled analgesia in combination with quadratus lumborum block (QLB) vs. transverse abdominis plane block (TAPB) on quality of recovery following major laparoscopic gastrointestinal surgery. Methods: and analysis: This is a prospective, randomized, controlled clinical trial with a 2 × 2 factorial design. A total of 120 adult patients undergoing laparoscopic major gastrointestinal surgery will be randomized, in a 1:1:1:1 ratio, to receive one of two patient-controlled analgesia regimens (based on oxycodone or sufentanil) and one of two regional blocks (QLB or TAPB). The primary outcome measure of this trial is the quality of recovery at 24 h after surgery, assessed using the 15-item quality of recovery (QoR-15) scale. The secondary outcomes include QoR-15 scores at 48 and 72 h after surgery; visceral and incisional pain at rest and while coughing at 1, 6, 24 and 48 h postoperatively; analgesic consumption within 0–24 h and 24–48 h postoperatively; need for rescue analgesia; postoperative flatus time; postoperative adverse events (sedation, nausea and vomiting, use of antiemetics, respiratory depression, and dizziness); and length of postoperative hospital stay. Discussion: The results of this trial will provide evidence for the optimal multimodal analgesic strategy to improve the quality of recovery for patients undergoing laparoscopic major gastrointestinal surgery. Trial registration: This trial was registered at the Chinese Clinical Trial Registry (www.chictr.org.cn, identifier: ChiCTR2400080766)

Functional variant of the carboxypeptidase M (CPM) gene may affect silica-related pneumoconiosis susceptibility by its expression: a multistage case-control study.

ObjectivesIn a genome-wide association study, we discovered chromosome 12q15 (defined as rs73329476) as a silica-related pneumoconiosis susceptibility region. However, the causal variants in this region have not yet been reported.MethodsWe systematically screened eight potentially functional single-neucleotide polymorphism (SNPs) in the genes near rs73329476 (carboxypeptidase M (CPM) and cleavage and polyadenylation specific factor 6 (CPSF6)) in a case-control study including 177 cases with silicosis and 204 healthy controls, matched to cases with years of silica dust exposure. We evaluated the associations between these eight SNPs and the development of silicosis. Luciferase reporter gene assays were performed to test the effects of selected SNP on the activity of CPM in the promoter. In addition, a two-stage case-control study was performed to investigate the expression differences of the two genes in peripheral blood leucocytes from a total of 64 cases with silicosis and 64 healthy controls with similar years of silica dust exposure as the cases.ResultsWe found a strong association between the mutant rs12812500 G allele and the susceptibility of silicosis (OR=1.45, 95% CI 1.03 to 2.04, p=0.034), while luciferase reporter gene assays indicated that the mutant G allele of rs12812500 is strongly associated with increased luciferase levels compared with the wild-type C allele (p&lt;0.01). Moreover, the mRNA (peripheral blood leucocytes) expression of the CPM gene was significantly higher in subjects with silicosis compared with healthy controls.ConclusionsThe rs12812500 variant of the CPM gene may increase silicosis susceptibility by affecting the expression of CPM, which may contribute to silicosis susceptibility with biological plausibility

The impacts of recent permafrost thaw on land–atmosphere greenhouse gas exchange

© The Author(s), 2014. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Environmental Research Letters 9 (2014): 045005, doi:10.1088/1748-9326/9/4/045005.Permafrost thaw and the subsequent mobilization of carbon (C) stored in previously frozen soil organic matter (SOM) have the potential to be a strong positive feedback to climate. As the northern permafrost region experiences as much as a doubling of the rate of warming as the rest of the Earth, the vast amount of C in permafrost soils is vulnerable to thaw, decomposition and release as atmospheric greenhouse gases. Diagnostic and predictive estimates of high-latitude terrestrial C fluxes vary widely among different models depending on how dynamics in permafrost, and the seasonally thawed 'active layer' above it, are represented. Here, we employ a process-based model simulation experiment to assess the net effect of active layer dynamics on this 'permafrost carbon feedback' in recent decades, from 1970 to 2006, over the circumpolar domain of continuous and discontinuous permafrost. Over this time period, the model estimates a mean increase of 6.8 cm in active layer thickness across the domain, which exposes a total of 11.6 Pg C of thawed SOM to decomposition. According to our simulation experiment, mobilization of this previously frozen C results in an estimated cumulative net source of 3.7 Pg C to the atmosphere since 1970 directly tied to active layer dynamics. Enhanced decomposition from the newly exposed SOM accounts for the release of both CO2 (4.0 Pg C) and CH4 (0.03 Pg C), but is partially compensated by CO2 uptake (0.3 Pg C) associated with enhanced net primary production of vegetation. This estimated net C transfer to the atmosphere from permafrost thaw represents a significant factor in the overall ecosystem carbon budget of the Pan-Arctic, and a non-trivial additional contribution on top of the combined fossil fuel emissions from the eight Arctic nations over this time period.This study was supported through grants provided as part of the National Science Foundation’s Arctic System Science Program (NSF OPP0531047), a Department of Energy (DOE) Early Career Award (DOEBER #3ERKP818), the National Aeronautics and Space Administration’s New Investigator Program (NNX10AT66G) and the NextGeneration Ecosystem Experiments (NGEE Arctic) project supported by the Office of Biological and Environmental Research in the DOE Office of Science

Stability and genetic insights of the co-existence of blaCTX-M-65, blaOXA-1, and mcr-1.1 harboring conjugative IncI2 plasmid isolated from a clinical extensively-drug resistant Escherichia coli ST744 in Shanghai

BackgroundCo-existence of colistin, β-lactam and carbapenem in multidrug-resistant Enterobacteriaceae isolates poses a serious threat to public health. In this study, we investigated and characterized the co-occurrence of blaCTX-M-65, blaOXA-1, and mcr-1.1 strain isolated from a clinical extensively-drug-resistant Escherichia coli ST744 in Shanghai.MethodsAntimicrobial susceptibility test was carried out by agar dilution methods. Whole genome sequencing was conducted, and resistance genes, and sequence types of colistin in E. coli isolates were analyzed. Plasmid stability and amino acid mutations were assessed in E. coli isolates.ResultsA colistin resistant E. coli ST744, named ECPX221, was identified out of 145 fecal samples collected. The strain carries a 60,168 IncI2 plasmid with the mcr-1.1 gene. The strain also has blaCTX-M-65, blaOXA-1, dfrA14, qnrS1, cmlA5, arr2, ampC, aph(4)-Ia, sul1, and aadA5 resistance genes. The plasmid pECPX221 was capable of conjugation with an efficiency of 2.6 × 10−2. Notably, 45% of the transconjugants were determined as mcr-1.1-harboring in the colistin-free environment after 60 generation of passage. No mutations occurred in pmrB, mgrB, and phoPQ gene in the mcr-1.1-harboring transconjugants. Bioinformatic analysis indicated pECPX221 shared highly similar backbone with the previously reported mcr-1.1-harboring pAH62-1, pMFDS1339.1, pSCZE4, and p2018-10-2CC. Furthermore, sequencing and phylogenetic analyses revealed a similarity between other MCR-1-homolog proteins, indicating that ECPX221 was colistin resistant.ConclusionThe stable transferable mcr-1.1-harboring plasmid found in the E. coli ST744 strain indicated the high risk to disseminate the extensively-drug-resistance phenotype among Enterobacteriaceae

Base-promoted reaction of C60Cl6 with thioamides: an access to [60] fullereno[1,9-d] thiazoles

[email protected]; [email protected] reaction of C60Cl6 with thioamides via a radical annulation to form fullereno thiazole derivatives is reported. The reaction is promoted by K2CO3, which might deprotonate thioamide to initiate a single electron transfer from thioamide anion to C60Cl6. The experiments with various thioamides establish the proposed base-promoted reaction as a facile route for synthesis of fullereno fused thiazole derivatives starting from C60Cl6, a prevalent synthon in fullerene chemistry. In addition, the tunable electrochemical properties of the fullereno thiazole products have been investigated for their potential photovoltaic application. (C) 2014 Elsevier Ltd. All rights reserved.973 Project 2014CB845601 National Science Foundation of China 21272190 21031004 U1205111 2139039

Measurement of the final states ωπ0\omega \pi^0, ρη\rho \eta, and ρη′\rho \eta^{'} from \psip electromagnetic decays and \ee annihilations

Cross sections and form factors for \ee \to \wpi, $\rho\eta$, and \rho\etap at center of mass energies of 3.650, 3.686, and 3.773 GeV are measured using data samples collected with the BESII detector at the BEPC. Also, the branching fractions of \psi(2S) \rar \wpi, $\rho\eta$, and \rho\etap are determined to be $(1.87^{+0.68}_{-0.62}\pm0.28)\times 10^{-5}$, $(1.78^{+0.67}_{-0.62}\pm0.17)\times 10^{-5}$, and $(1.87^{+1.64}_{-1.11}\pm0.33)\times10^{-5}$, respectively.Comment: 8 pages, 4 figures, 4 table