125 research outputs found
A Quantum Internet Architecture
Entangled quantum communication is advancing rapidly, with laboratory and
metropolitan testbeds under development, but to date there is no unifying
Quantum Internet architecture. We propose a Quantum Internet architecture
centered around the Quantum Recursive Network Architecture (QRNA), using
RuleSet-based connections established using a two-pass connection setup.
Scalability and internetworking (for both technological and administrative
boundaries) are achieved using recursion in naming and connection control. In
the near term, this architecture will support end-to-end, two-party
entanglement on minimal hardware, and it will extend smoothly to multi-party
entanglement and the use of quantum error correction on advanced hardware in
the future. For a network internal gateway protocol, we recommend (but do not
require) qDijkstra with seconds per Bell pair as link cost for routing; the
external gateway protocol is designed to build recursively. The strength of our
architecture is shown by assessing extensibility and demonstrating how robust
protocol operation can be confirmed using the RuleSet paradigm.Comment: 17 pages, 7 numbered figure
Role of RNA-Binding Proteins in MAPK Signal Transduction Pathway
Mitogen-activated protein kinases (MAPKs), which are found in all eukaryotes, are signal transducing enzymes playing a central role in diverse biological processes, such as cell proliferation, sexual differentiation, and apoptosis. The MAPK signaling pathway plays a key role in the regulation of gene expression through the phosphorylation of transcription factors. Recent studies have identified several RNA-binding proteins (RBPs) as regulators of MAPK signaling because these RBPs bind to the mRNAs encoding the components of the MAPK pathway and regulate the stability of their transcripts. Moreover, RBPs also serve as targets of MAPKs because MAPK phosphorylate and regulate the ability of RBPs to bind and stabilize target mRNAs, thus controlling various cellular functions. In this review, we present evidence for the significance of the MAPK signaling in the regulation of RBPs and their target mRNAs, which provides additional information about the regulatory mechanism underlying gene expression. We further present evidence for the clinical importance of the posttranscriptional regulation of mRNA stability and its implications for drug discovery
A Chinese Herbal Medicine, Tokishakuyakusan, Reduces the Worsening of Impairments and Independence after Stroke: A 1-Year Randomized, Controlled Trial
In post-stroke patients, the recurrence of stroke and progression of impairments lead to a bedridden state and dementia. As for their treatments, only anti-hypertension and anti-coagulation therapies to prevent the recurrence of stroke are available. In Asia, post-stroke patients with impairments are often treated with herbal medicine. The present study evaluated the effectiveness of tokishakuyakusan (TS) in improving the impairment and independence in post-stroke patients. Thirty-one post-stroke patients (mean age = 81.4 years) were recruited and enrolled. Participants were randomly assigned to the TS group (n = 16) or non-treatment (control) group (n = 15) and treated for 12 months. Impairments were assessed using the Stroke Impairment Assessment Set (SIAS). Independence was evaluated using the functional independence measure (FIM). For each outcome measure, mean change was calculated every 3 months. The results were that impairments according to SIAS did not significantly change in the TS group. In contrast, SIAS significantly worsened in the control group. There was a significant difference between the two groups. In each term of SIAS, affected lower extremity scores, abdominal muscle strength, function of visuospatial perception, and so forth. in the TS group were better than those in the control group. Independence according to FIM did not change significantly in the TS group. In contrast, FIM significantly worsened in the control group. There was also a significant difference between the two groups. In conclusion, TS was considered to suppress the impairments of lower limbs and to exert a favorable effect on cerebral function for post-stroke patients
QuISP: a Quantum Internet Simulation Package
We present an event-driven simulation package called QuISP for large-scale
quantum networks built on top of the OMNeT++ discrete event simulation
framework. Although the behavior of quantum networking devices have been
revealed by recent research, it is still an open question how they will work in
networks of a practical size. QuISP is designed to simulate large-scale quantum
networks to investigate their behavior under realistic, noisy and heterogeneous
configurations. The protocol architecture we propose enables studies of
different choices for error management and other key decisions. Our confidence
in the simulator is supported by comparing its output to analytic results for a
small network. A key reason for simulation is to look for emergent behavior
when large numbers of individually characterized devices are combined. QuISP
can handle thousands of qubits in dozens of nodes on a laptop computer,
preparing for full Quantum Internet simulation. This simulator promotes the
development of protocols for larger and more complex quantum networks.Comment: 17 pages, 12 figure
Effect of Zn substitution for Cu on CaNaCuOCl near the hole concentration of 1/8 per Cu
A weakening of superconductivity upon substitution of Cu by Zn (0.5~1 %) is
observed in a high-T_c cuprate, Ca_{2-x}Na_xCuO2Cl2, near the hole
concentration of 1/8 per Cu. The superconducting transition temperature and its
volume fraction, estimated by magnetic susceptibility, exhibit a sizable
anomaly for x=0.12~0.14, where the slowing down of Cu spin fluctuations below 5
K is demonstrated by muon spin relaxation experiments. These observations are
in close resemblance to other typical cuprates including YBa2Cu3O_{7-d}, and
Bi2Sr2Ca_{1-x}Y_xCu2O_{8+d}, providing further evidence that Zn-induced
"stripe" correlation is a universal feature of high-T_c cuprate superconductors
common to that of La_{2-x}A_{x}CuO4 (A=Ba, Sr).Comment: 4 pages, 3 figure
Size-selective encapsulation property of unimolecular reverse micelle consisting of hyperbranched D-glucan core and L-leucine ethyl ether shell
金沢大学理工研究域自然システム学系The synthesis of a unimolecular reverse micelle (3) consisting of hyper-branched D-glucan as the core and L-leucine ethyl ester as the shell was accomplished through the carbamation reaction of the hyperbranched D-glucan (1) with the N-carbonyl L-leucine ethyl ester (2) in pyridine at 100 °C. The polymer 3 was soluble in a large variety of organic solvents, such as methanol, acetone, chloroform, and ethyl acetate, and insoluble in water, which remarkably differed from the solubility of 1. The solubilities of 3 were also changed by the substitution degrees of the L-leucine moiety. The encapsulation ability of 3 toward water-soluble dyes has been investigated. These results indicated that 3 was a unimolecular reverse micelle with an encapsulation ability toward hydrophilic dye molecules. In addition, 3 showed an molecular size-selective encapsulation ability. Copyright © 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
PKN3 is the major regulator of angiogenesis and tumor metastasis in mice
PKN, a conserved family member related to PKC, was the first protein kinase identified as a target of the small GTPase Rho. PKN is involved in various functions including cytoskeletal arrangement and cell adhesion. Furthermore, the enrichment of PKN3 mRNA in some cancer cell lines as well as its requirement in malignant prostate cell growth suggested its involvement in oncogenesis. Despite intensive research efforts, physiological as well as pathological roles of PKN3 in vivo remain elusive. Here, we generated mice with a targeted deletion of PKN3. The PKN3 knockout (KO) mice are viable and develop normally. However, the absence of PKN3 had an impact on angiogenesis as evidenced by marked suppressions of micro-vessel sprouting in ex vivo aortic ring assay and in vivo corneal pocket assay. Furthermore, the PKN3 KO mice exhibited an impaired lung metastasis of melanoma cells when administered from the tail vein. Importantly, PKN3 knock-down by small interfering RNA (siRNA) induced a glycosylation defect of cell-surface glycoproteins, including ICAM-1, integrin β1 and integrin α5 in HUVECs. Our data provide the first in vivo genetic demonstration that PKN3 plays critical roles in angiogenesis and tumor metastasis, and that defective maturation of cell surface glycoproteins might underlie these phenotypes
Role of the RNA-Binding Protein Nrd1 in Stress Granule Formation and Its Implication in the Stress Response in Fission Yeast
We have previously identified the RNA recognition motif (RRM)-type RNA-binding protein Nrd1 as an important regulator of the posttranscriptional expression of myosin in fission yeast. Pmk1 MAPK-dependent phosphorylation negatively regulates the RNA-binding activity of Nrd1. Here, we report the role of Nrd1 in stress-induced RNA granules. Nrd1 can localize to poly(A)-binding protein (Pabp)-positive RNA granules in response to various stress stimuli, including heat shock, arsenite treatment, and oxidative stress. Interestingly, compared with the unphosphorylatable Nrd1, Nrd1DD (phosphorylation-mimic version of Nrd1) translocates more quickly from the cytoplasm to the stress granules in response to various stimuli; this suggests that the phosphorylation of Nrd1 by MAPK enhances its localization to stress-induced cytoplasmic granules. Nrd1 binds to Cpc2 (fission yeast RACK) in a phosphorylation-dependent manner and deletion of Cpc2 affects the formation of Nrd1-positive granules upon arsenite treatment. Moreover, the depletion of Nrd1 leads to a delay in Pabp-positive RNA granule formation, and overexpression of Nrd1 results in an increased size and number of Pabp-positive granules. Interestingly, Nrd1 deletion induced resistance to sustained stresses and enhanced sensitivity to transient stresses. In conclusion, our results indicate that Nrd1 plays a role in stress-induced granule formation, which affects stress resistance in fission yeast
Exercise before breakfast increases 24-h fat oxidation in female subjects
BackgroundExercise performed in a postprandial state does not increase 24-h fat oxidation of male and female subjects. Conversely, it has been shown in male subjects that exercise performed in a postabsorptive state increases 24-h fat oxidation compared with that in sedentary control and that with exercise trials performed after breakfast, lunch, or dinner. There is a paucity of study evaluating the effect of exercise performed in a postabsorptive state in female subjects.MethodNine young female subjects participated in indirect calorimetry measurement over 24-h using a room-size metabolic chamber in which subjects remained sedentary or performed 60 min exercise before breakfast at 50% of . Exercise was accompanied by an increase in energy intake to ensure that subjects were in a similar state of energy balance over 24 h for the two trials.FindingsCompared with the sedentary condition, exercise performed before breakfast increased 24-h fat oxidation (519 ± 37 vs. 400 ± 41 kcal/day). Time courses of relative energy balance differed between trials with transient negative energy balance observed before breakfast. The lowest values of relative energy balance observed during the 24-h calorimetry, i.e., transient energy deficit, were greater in exercise trials than in sedentary trials. The transient deficit in carbohydrate balance was also observed before breakfast, and magnitude of the deficit was greater in exercise trial compared to that of sedentary trial.InterpretationUnder energy-balanced conditions, exercise performed in a post-absorptive state increases 24-h fat oxidation in female subjects. The effect of exercise performed before breakfast can be attributed to nutritional state: a transient deficit in energy and carbohydrate at the end of exercise
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