Improvement of the old reductions of irregular satellites using the first publications of the data

Program available at: http://www.imcce.fr/hosted_sites/naroo/program.htmlInternational audienceThe use of long-exposure photographic plates made the discovery of additional natural satellites possible. The first satellite to be discovered in this manner, Phoebe, was found in 1899 by W.H. Pickering. A reliable model of satellite motion must be constructed with high accurate observations and with data spreading over a period as long as possible. Some old literatures have given the positions of the natural satellites and the reference stars for determining its positions. At that time, the catalogue they used did not contain enough stars, so there were not many catalogue stars on the plates. Because of the unsatisfactory precision of the old catalogue at the epoch and the imprecise measurements on the plate, the positions of the reference stars were not very precise. At present, although we have no plates, we can reduce the positions of the natural satellites from the row data provided in these literatures with modern precise astrometric catalogues, such as PPM and UCAC2. The purpose of this work is to reduce the old observations of Phoebe (Saturn IX), in order to improve its orbit

Limit of achievable information rates in EDFA and Raman amplified transmission systems using nonlinearity compensation

Optical networks form an integral part of the world-wide communication infrastructure and nowadays over 95% of data traffic is carried over fibres. Erbium-doped fibre amplifiers (EDFAs) and Raman amplifiers have made it possible to extend the usable fibre bandwidth to increase the achievable capacity of optical communications in past decades to meet the ever-growing information rate demands. However, these amplification technologies are now viewed as limiting the accessible optical spectrum to ~5 THz and ~10 – 15 THz, respectively. Currently, the presence of Kerr effects in fibre channels has been largely regarded as the major bottleneck for enhancing achievable information rates of optical communications. Signal performance degradations due to fibre nonlinearities are more severe in the systems utilising larger transmission bandwidths, closer channel spacing and higher-order modulation formats. In this work, we will study the impact and compensation of Kerr effects to analyse the performance of long-haul optical fibre communication systems using EDFAs and Raman amplifiers. Achievable information rates of such ultra-wideband optical transmission systems will be discussed considering nonlinearity compensation and probabilistic shaping techniques

Achievable Information Rates in C-band Nonlinear Coherent Optical Communication Systems

Information rates of C-band Nyquist-spaced optical fiber communication systems with erbium-doped fiber amplifier (EDFA) and distributed Raman amplification (DRA) schemes were discussed. Results indicate that the nonlinearity compensation performance depends on transmission distances and modulation formats

Effects of Transcutaneous Electrical Acustimulation on Refractory Gastroesophageal Reflux Disease

Objective. To investigate effects and possible mechanisms of transcutaneous electrical acustimulation (TEA) performed by a wearable watch-size stimulator for refractory gastroesophageal reflux disease (RGERD). Methods. Twenty patients diagnosed as RGERD were enrolled in the study and randomly divided into four groups: esomeprazole group (Group A), esomeprazole combined with TEA group (Group B), esomeprazole combined with sham-TEA group (Group C), and esomeprazole combined with domperidone group (Group D). HRM and 24 h pH-impedance monitoring and GerdQ score were used to measure related indexes before and after treatment. Results. (1) TEA significantly increased LESP, compared with PPI treatment only or PPI plus sham-TEA. After pairwise comparison, LESP of Group B was increased more than Group A (P=0.008) or Group C (P=0.021). (2) PPI plus TEA decreased not only the number of acid reflux episodes but also the number of weak acid reflux episodes (P=0.005). (3) Heartburn and reflux symptoms were improved more with PPI + TEA than with PPI treatment only or PPI plus sham-TEA (GerdQ scores, P=0.001). Conclusion. TEA can improve symptoms in RGERD patients by increasing LESP and decreasing events of weak acid reflux and acid reflux; addition of TEA to esomeprazole significantly enhances the effect of TEA

A concise and straightforward approach to total synthesis of (+)-Strictifolione and formal synthesis of Cryptofolione via a unified strategy

YesWe describe a concise and straightforward approach to the total syntheses of (+)-Strictifolione and Cryptofolione in the longest linear sequences of four steps and six steps from 3-phenyl propanal and trans-cinnamaldehyde, respectively. The route utilized a titanium tetraisopropoxide/(R)-[1,1'-binaphthalene]-2,2'-diol catalyzed Mukaiyama aldol reaction, indium(0)-promoted Barbier reaction, and olefin cross-metathesis as the key reactions.National Science Foundation of China [21062088, 21562020, and 21462004], the Science and Technology Plan Project of Jiangxi Province [No. 20151BBG70028, 20142BBE50006] and State Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources [CMEMR2014-A04] for the funding support

Synthesis of electroneutralized amphiphilic copolymers with peptide dendrons for intramuscular gene delivery

Intramuscular gene delivery materials are of great importance in plasmid-based gene therapy system, but there is limited information so far on how to design and synthesize them. A previous study showed that the peptide dendron-based triblock copolymer with its components arranged in a reversed biomembrane architecture could significantly increase intramuscular gene delivery and expression. Herein, we wonder whether copolymers with biomembrane-mimicking arrangement may have similar function on intramuscular gene delivery. Meanwhile, it is of great significance to uncover the influence of electric charge and molecular structure on the function of the copolymers. To address the issues, amphiphilic triblock copolymers arranged in hydrophilic-hydrophobic-hydrophilic structure were constructed despite the paradoxical characteristics and difficulties in synthesizing such hydrophilic but electroneutral molecules. The as-prepared two copolymers, dendronG2(l-lysine-OH)-poly propylene glycol2k(PPG2k)-dendronG2(l-lysine-OH) (rL2PL2) and dendronG3(l-lysine-OH)-PPG2k-dendronG3(l-lysine-OH) (rL3PL3), were in similar structure but had different hydrophilic components and surface charges, thus leading to different capabilities in gene delivery and expression in skeletal muscle. rL2PL2 was more efficient than Pluronic L64 and rL3PL3 when mediating luciferase, β-galactosidase, and fluorescent protein expressions. Furthermore, rL2PL2-mediated growth-hormone-releasing hormone expression could significantly induce mouse body weight increase in the first 21 days after injection. In addition, both rL2PL2 and rL3PL3 showed good in vivo biosafety in local and systemic administration. Altogether, rL2PL2-mediated gene expression in skeletal muscle exhibited applicable potential for gene therapy. The study revealed that the molecular structure and electric charge were critical factors governing the function of the copolymers for intramuscular gene delivery. It can be concluded that, combined with the previous study, both structural arrangements either reverse or similar to the biomembrane are effective in designing such copolymers. It also provides an innovative way in designing and synthesizing new electroneutralized triblock copolymers, which could be used safely and efficiently for intramuscular gene delivery

Aptamer Antagonists of Myelin-Derived Inhibitors Promote Axon Growth

Myelin of the adult central nervous system (CNS) is one of the major sources of inhibitors of axon regeneration following injury. The three known myelin-derived inhibitors (Nogo, MAG, and OMgp) bind with high affinity to the Nogo-66 receptor (NgR) on axons and limit neurite outgrowth. Here we show that RNA aptamers can be generated that bind with high affinity to NgR, compete with myelin-derived inhibitors for binding to NgR, and promote axon elongation of neurons in vitro even in the presence of these inhibitors. Aptamers may have key advantages over protein antagonists, including low immunogenicity and the possibility of ready modification during chemical synthesis for stability, signaling, or immobilization. This first demonstration that aptamers can directly influence neuronal function suggests that aptamers may prove useful for not only healing spinal cord and other neuronal damage, but may be more generally useful as neuromodulators

Effects and Mechanisms of Transcutaneous Electroacupuncture on Chemotherapy-Induced Nausea and Vomiting

Nausea and vomiting are one of the major complications of chemotherapy for cancers. The aim of this study is to investigate the emetic effects and mechanisms involving serotonin and dopamine of needleless transcutaneous electroacupuncture (TEA) at Neiguan (PC6) and Jianshi (PC5) on chemotherapy-induced nausea and vomiting in patients with cancers. Seventy-two patients with chemotherapy were randomly divided into sham-TEA group (sham-TEA, n=34) and TEA group (n=38). TEA was performed at PC 6 and PC 5 (1 h, bid) in combination with granisetron. Sham-TEA was delivered at nonacupoints using the same parameters. We found the following. (1) In the acute phase, the conventional antiemetic therapy using Ondansetron effectively reduced nausea and vomiting; the addition of TEA did not show any additive effects. In the delayed phase, however, TEA significantly increased the rate of complete control (P<0.01) and reduced the nausea score (P<0.05), compared with sham-TEA. (2) TEA significantly reduced serum levels of 5-HT and dopamine in comparison with sham-TEA. Those results demonstrate that needleless transcutaneous electroacupuncture at PC6 using a watch-size digital stimulator improves emesis and reduces nausea in the delayed phase of chemotherapy in patients with cancers. This antiemetic effect is possibly mediated via mechanisms involving serotonin and dopamine

First order transition in trigonal structure CaMn2P2{\textbf{Ca}}{\textbf{Mn}}_{2}{\textbf{P}}_{2}

We report structural and physical properties of the single crystalline ${\mathrm{Ca}}{\mathrm{Mn}}_{2}{\mathrm{P}}_{2}$. The X-ray diffraction(XRD) results show that ${\mathrm{Ca}}{\mathrm{Mn}}_{2}{\mathrm{P}}_{2}$ adopts the trigonal ${\mathrm{Ca}}{\mathrm{Al}}_{2}{\mathrm{Si}}_{2}$-type structure. Temperature dependent electrical resistivity $\rho(T)$ measurements indicate an insulating ground state for ${\mathrm{Ca}}{\mathrm{Mn}}_{2}{\mathrm{P}}_{2}$ with activation energies of 40 meV and 0.64 meV for two distinct regions, respectively. Magnetization measurements show no apparent magnetic phase transition under 400 K. Different from other ${\mathrm{A}}{\mathrm{Mn}}_{2}{\mathrm{Pn}}_{2}$ (A = Ca, Sr, and Ba, and Pn = P, As, and Sb) compounds with the same structure, heat capacity $C_{\mathrm{p}}(T)$ and $\rho(T)$ reveal that ${\mathrm{Ca}}{\mathrm{Mn}}_{2}{\mathrm{P}}_{2}$ has a first-order transition at $T$ = 69.5 K and the transition temperature shifts to high temperature upon increasing pressure. The emergence of plenty of new Raman modes below the transition, clearly suggests a change in symmetry accompanying the transition. The combination of the structural, transport, thermal and magnetic measurements, points to an unusual origin of the transition.Comment: 6 pages, 6 figures. Accepted by Europhysics Letter

Fed-dfe: A decentralized function encryption-based privacy-preserving scheme for federated learning

Federated learning is a distributed learning framework which trains globalmodels by passing model parameters instead of raw data. However, the training mechanism for passing model parameters is still threatened by gradient inversion, inference attacks, etc. With a lightweight encryption overhead, function encryption is a viable secure aggregation technique in federation learning, which is often used in combination with differential privacy. The function encryption in federal learning still has the following problems: A) Traditional function encryption usually requires a trust third party (TTP) to assign the keys. If a TTP colludes with a server, the security aggregationmechanismcan be compromised. b)When using differential privacy in combination with function encryption, the evaluation metrics of incentive mechanisms in the traditional federal learning become invisible. In this paper, we propose a hybrid privacy-preserving scheme for federated learning, called Fed-DFE. Specifically, we present a decentralized multi-client function encryption algorithm. It replaces the TTP in traditional function encryption with an interactive key generation algorithm, avoiding the problem of collusion. Then, an embedded incentive mechanism is designed for function encryption. It models the real parameters in federated learning and finds a balance between privacy preservation and model accuracy. Subsequently, we implemented a prototype of Fed-DFE and evaluated the performance of decentralized function encryption algorithm. The experimental results demonstrate the effectiveness and efficiency of our scheme