Modeling Hidden Nodes Collisions in Wireless Sensor Networks: Analysis Approach

This paper studied both types of collisions. In this paper, we show that advocated solutions for coping with hidden node collisions are unsuitable for sensor networks. We model both types of collisions and derive closed-form formula giving the probability of hidden and visible node collisions. To reduce these collisions, we propose two solutions. The first one based on tuning the carrier sense threshold saves a substantial amount of collisions by reducing the number of hidden nodes. The second one based on adjusting the contention window size is complementary to the first one. It reduces the probability of overlapping transmissions, which reduces both collisions due to hidden and visible nodes. We validate and evaluate the performance of these solutions through simulations

Biomimetic Syntheses of Rubialatins A, B and Related Congeners

The first total syntheses of rubialatins A and B, two newly discovered naphtho­hydro­quinone dimers, were achieved with high efficiency and elegancy through rationally designed biomimetic approaches. The tandem ring contraction/Michael addition/aldol reaction followed by oxidation enabled the rapid access of prerubialatin from readily available precursors, which then diverted into rubialatins A and B via epoxidation and photoinduced skeletal rearrangement, respectively. Moreover, several new rubialatin congeners were also obtained along the synthetic tour, some of which were proved to be authentic natural products

Synthesis of Polysubstituted Furans via Rh(II)-Catalyzed [2 + 3] Annulation of <i>N</i>‑Sulfonyl-1,2,3-triazoles with Enaminones

An unprecedented [2 + 3] annulation of N-sulfonyl-1,2,3-triazoles with enaminones is reported for the access of polysubstituted furans. The key to the success of the transformations lies in the use of Rh(II)–Brønsted acid as cooperative catalysts. Unlike the conventional annulations of N-sulfony-l-1,2,3-triazoles, the Rh(II)-azavinyl carbenes species play dual functions in this work, enabled by the cleavage of the C(sp2)−N bond. The mechanism studies suggested that an intermolecular rearrangement of the TsNH– group is crucial to the annulation process

Interaction between flavin mononucleotide-containing azoreductase and azo dyes

<p>Azoreductase, a flavin mononucleotide-containing oxidoreductase from <i>Escherichia coli</i>, can catalyze the reduction of azo dyes to form aromatic amine compounds. Few spectroscopic studies have explored the binding mode of azo dyes or the role of the arginine at site 59 in Azoreductase. In this article, protein engineering strategy has been used to construct one mutant in which the arginine residue at site 59 was mutated to glycine. Fluorescence spectroscopic data showed that the addition of Methyl Red and Methyl Orange resulted in the fluorescence quenching of the cofactor flavin mononucleotide bound to Azoreductase. The association constant was fitted using the standard binding equation instead of the Stern-Volmer equation. The results showed that the mutation from the arginine to glycine at site 59 weakened the association constant from 2.21 × 10⁵ L.mol⁻¹ to 4.55 × 10⁴ L.mol⁻¹ at 25°C. A similar phenomenon was also observed when Methyl Orange was used as a substrate. In each case, the association constant tended to decrease as the temperature increased from 25°C to 37°C. Thermodynamic parameter analysis revealed that the interaction type changed from a van der Waals interaction (between Azoreductase and the dyes) to a hydrogen bonding interaction (between the mutant and the dyes). Moleculcar docking was also performed in this work to provide some support for the binding mode and binding stability between Azoreductase/mutant and azo dyes.</p

Temperature-Dependent Enantio- and Diastereodivergent Synthesis of Amino Acids with One or Multiple Chiral Centers

A general and facile methodology for temperature-dependent enantiodivergent and diastereodivergent synthesis of amino acids with one or multiple chiral centers was developed. Camphor-based tricyclic iminolactones attack electrophiles from the <i>endo</i> face at low temperature (−78 to −40 °C) and from the <i>exo</i> face at high temperature (−10 to 25 °C)

The pairwise association between expression of HSP10 and c-PARP proteins in the 103 cases of astrocytoma.

<p>The pairwise association between expression of HSP10 and c-PARP proteins in the 103 cases of astrocytoma.</p

Expression of HSP10 and c-PARP proteins in astrocytoma compared to non-tumor control brain tissues.

<p>Results showed that there were significant differences between the groups which were statistically evaluated by chi-square test (<i>P</i> < 0.05).</p

Generalization of the Right Acute Stroke Prevention Strategies in Reducing in-Hospital Delays

<div><p>The aim of this study was to reduce the door-to-needle (DTN) time of intravenous thrombolysis (IVT) in acute ischemic stroke (AIS) through a comprehensive, hospital-based implementation strategy. The intervention involved a systemic literature review, identifying barriers to rapid IVT treatment at our hospital, setting target DTN time intervals, and building an evolving model for IVT candidate selection. The rate of non-in-hospital delay (DTN time ≤ 60 min) was set as the primary endpoint. A total of 348 IVT cases were enrolled in the study (202 and 146 in the pre- and post-intervention group, respectively). The median age was 61 years in both groups; 25.2% and 26.7% of patients in the pre- and post-intervention groups, respectively, were female. The post-intervention group had higher rates of dyslipidemia and minor stroke [defined as National Institutes of Health Stroke Scale (NIHSS) ≤ 3]; less frequent atrial fibrillation; higher numbers of current smokers, heavy drinkers, referrals, and multi-model head imaging cases; and lower NIHSS scores and blood sugar level (all P < 0.05). All parameters including DTN, door-to-examination, door-to-imaging, door-to-laboratory, and final-test-to-needle times were improved post-intervention (all P < 0.05), with net reductions of 63, 2, 4, 28, and 23 min, respectively. The rates of DTN time ≤ 60 min and onset-to-needle time ≤ 180 min were significantly improved by the intervention (pre: 9.9% vs. post: 60.3%; P < 0.001 and pre: 23.3% vs. post: 53.4%; P < 0.001, respectively), which was accompanied by an increase in the rate of neurological improvement (pre: 45.5% vs. post: 59.6%; P = 0.010), while there was no change in incidence of mortality or systemic intracranial hemorrhage at discharge (both P > 0.05). These findings indicate that it is possible to achieve a DTN time ≤ 60 min for up to 60% of hospitals in the current Chinese system, and that this logistical change can yield a notable improvement in the outcome of IVT patients.</p></div

Kaplan-Meier curves according to expression of HSP10 and c-PARP proteins and common expression of two proteins divided into high and low expression.

<p>A: High expression of HSP10 was significantly correlated to poor prognosis of astrocytoma patients (P = 0.001, two sided). B: High expression of c-PARP did not significantly relate with survival of astrocytoma patients (<i>P</i> = 0.650, two sided). C: Astrocytoma patients with high expression of HSP10 and low expression of c-PARP had significantly short survival times (<i>P</i> < 0.019, two sided). D: Astrocytoma patients with high pathologic grades were evidently poor overall survival (<i>P</i>< 0.001, two sided).</p

Expression of HSP10 and c-PARP proteins in astrocytoma was detected by immunohistochemistry.

<p>1-A, B: Positive expression of HSP10 was located in the cytoplasm of astrocytoma cells (high expression) and non-tumor control brain tissues (low expression) (20x, IHC, DAB staining). 1-C, D: Positive staining of c-PARP (arrows) was identified in the nucleus of astrocytoma cells (low expression: low apoptotic indices, AIs) and in the neurons of non-tumor control brain tissues (high expression: high AIs) (20x, IHC, DAB staining).</p