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Ultra‐high performance concrete (UHPC) is an emerging class of cementitious materials with the strength and durability characteristics that far exceed those of normal‐strength concrete (NSC). While the use of UHPC in bridge structures has significantly advanced, the same cannot be stated for building structures. Among possible building applications, this study focuses on the use of UHPC in shear walls, where a significant loading demand is anticipated from the lateral loads due to wind and/or earthquake events. Upon validating a set of finite‐element models with the experimental test results, a holistic investigation has been performed in the current study to evaluate a variety of UHPC shear walls. In particular, the main structural response measures, including initial stiffness, force‐displacement relationship, and strength loss under cyclic lateral loads, have been extracted and compared. The study has been then extended to systematically investigate the effects of key design variables, such as wall thickness, aspect ratio, axial force, steel reinforcement, presence of boundary elements, and strength of embedded steel bars. The outcome of this study provides the building sector with firsthand information regarding the possibility of replacing NSC with UHPC in shear walls. This will be an important step forward to improve the safety and performance of building structures, especially where they are exposed to a high risk of wind and/or earthquake hazards. [ABSTRACT FROM AUTHOR]

Objectives: To explore the association between timing of diagnosis of common autosomal trisomies, maternal age, and socio-economic status (SES).Design: Retrospective study of cytogenetic diagnoses of trisomy 21 (T21), trisomy 18 (T18), and trisomy 13 (T13) in Victoria, Australia, in 2015 to 2016, stratified by timing (prenatal less than 17 weeks gestation, prenatal including or greater than or 17 weeks gestation, and postnatal before 12 months of age), maternal age, and SES region. Utilisation of prenatal testing following a live-born T21 infant was ascertained via record linkage.Results: Among 160 230 total births were 571 diagnoses of T21 and 246 of T18/T13. The overall and live birth prevalences of T21 were 3.56 and 0.47 per 1000 births, respectively. Compared with women from disadvantaged SES regions, women from high SES regions were more likely to have a prenatal diagnosis of a trisomy before 17 weeks than after (P < .01) and less likely to have a live-born T21 infant than a prenatal diagnosis (P < .01). There was a significant trend to higher live birth rates of T21 with lower SES (P = .004). The majority (68.5%) of women who gave birth to a live infant with T21 did not utilise prenatal testing.Conclusion: There is a significant relationship between lower SES, later prenatal diagnosis of trisomy, and higher live birth rate of T21 in Victoria. [ABSTRACT FROM AUTHOR]

Background and Purpose: GAT107 ((3aR,4S,9bS)-4-(4-bromo-phenyl)-3a,4,5,9b-tetrahydro-3H-cyclopenta-[c]quinoline-8-sulfonamide) is a positive allosteric modulator (PAM) and agonist of α7 nicotinic acetylcholine receptors (nAChRs)that can cause a prolonged period of primed potentiation of acetylcholine responses after drug washout. NS6740 is a silent agonist of α7 nAChRs that has little or no efficacy for activating the ion channel but induces stable desensitization states, some of which can be converted into channel-active states by PAMs. Although GAT107 and NS6740 appear to stably induce different non-conducting states, both agents are effective treatment for inflammation and inflammatory pain models. We sought to better understand how both of these drugs that have opposite effects on channel activation could regulate signal transduction.Experimental Approach: Voltage-clamp experiments were conducted with α7 nAChRs expressed in Xenopus oocytes.Key Results: Long-lived sensitivity to a PAM or to an agonist was produced by NS6740 or GAT107 respectively. With sequential applications, these two drugs induced varying levels of persistent activation, which is a unique condition for a receptor that is known for rapid desensitization. The non-conducting states induced by NS6740 or GAT107 differ in their sensitivity to an α7 nAChR-selective antagonist and in how effectively they promote current.Conclusions& Implications: Our data suggest that the persistent currents represent a dynamic interconversion between different stable desensitized states and the PAM-inducible conducting states. However, the similarity of NS6740 and GAT107 effects on inflammation and pain suggests that the different stable non-conducting states have common activity on signal transduction.Linked Articles: This article is part of a themed section on Nicotinic Acetylcholine Receptors. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v175.11/issuetoc. [ABSTRACT FROM AUTHOR]

Background and Purpose: Orthosteric agonists and positive allosteric modulators (PAMs) of the α7 nicotinic ACh receptor (nAChR) represent novel therapeutic approaches for pain modulation. Moreover, compounds with dual function as allosteric agonists and PAMs, known as ago-PAMs, add further regulation of receptor function.Experimental Approach: Initial studies examined the α7 ago-PAM, GAT107, in the formalin, complete Freund's adjuvant (CFA), LPS inflammatory pain models, the chronic constriction injury neuropathic pain model and the tail flick and hot plate acute thermal nociceptive assays. Additional studies examined the locus of action of GAT107 and immunohistochemical markers in the dorsal horn of the spinal cord in the CFA model.Key Results: Complementary pharmacological and genetic approaches confirmed that the dose-dependent antinociceptive effects of GAT107 were mediated through α7 nAChR. However, GAT107 was inactive in the tail flick and hot plate assays. In addition, GAT107 blocked conditioned place aversion elicited by acetic acid injection. Furthermore, intrathecal, but not intraplantar, injections of GAT107 reversed nociception in the CFA model, suggesting a spinal component of action. Immunohistochemical evaluation revealed an increase in the expression of astrocyte-specific glial fibrillary acidic protein and phosphorylated p38MAPK within the spinal cords of mice treated with CFA, which was attenuated by intrathecal GAT107 treatment. Importantly, GAT107 did not elicit motor impairment and continued to produce antinociceptive effects after subchronic administration in both phases of the formalin test.Conclusions and Implications: Collectively, these results provide the first proof of principle that α7 ago-PAMs represent an effective pharmacological strategy for treating inflammatory and neuropathic pain. [ABSTRACT FROM AUTHOR]

A novel small-signal state-space model is formulated for the commonly used synchronous reference frame phase-locked loop (SRF-PLL). Using this model, the effect of dc offsets as a function of SRF-PLL design parameters is quantified. It is shown that the unit vectors produced by the phase-locked loop (PLL) will have dc offsets when the input contains dc offsets. This can result in dc injection to the grid, which is highly undesirable. A systematic design method is proposed which ensures that dc injection to the grid is within the prescribed grid interconnection standards. In this design, SRF-PLL bandwidth is analytically computed for different levels of dc offsets in the input. The proposed design is compared with conventional pre-filter-based designs addressing the dc offset issue. The proposed design method results in the fastest transient response for given worst-case input dc offset without changing the PLL structure. Such a design for the SRF-PLL is computationally less intensive and is preferable when low-end digital controllers are used. The analytical results have been verified experimentally. [ABSTRACT FROM AUTHOR]

Objective To analyse the results of the first 2 years of a QF-PCR stand-alone testing strategy for the prenatal diagnosis of aneuploidy in the London region and to determine the advantages and disadvantages of this policy. Methods A review of the results of 9737 prenatal samples received for exclusion of chromosome abnormalities. All samples were subjected to QF-PCR testing for common aneuploidies but only samples fulfilling specific criteria subsequently had a full karyotype analysis. Results Of the 9737 samples received, 10.3% had a chromosome abnormality detected by QF-PCR testing. Of the 7284 samples received with no indication for karyotype analysis, 25 (0.3%) received a normal QF-PCR result but subsequently had an abnormal karyotype detected either prenatally as a privately funded test or postnatally. Of these samples, without subsequent abnormal ultrasound findings, five had a chromosome abnormality associated with a poor prognosis, representing 0.069% of samples referred for Down syndrome testing. Conclusion While back-up karyotyping is required for some samples, using QF-PCR as a stand-alone prenatal test for pregnancies without ultrasound abnormalities reduces costs, provides rapid delivery of results, and avoids ambiguous and uncertain karyotype results, reducing parental anxiety. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

An efficient microwave-assisted synthesis of cyclopentene ring-fused tetrahydroquinolines using a three-component Povarov reaction is reported. [ABSTRACT FROM AUTHOR]

In this article, we present a graph theoretic method to visualize and analyze the system behavior under different operating conditions. The system attributes (or variables) are the nodes in the graphs, and partial correlation between a pair of attributes defines the distance between corresponding nodes, resulting in a fully connected graph. Then, the redundant links are reduced using Pathfinder Network Scaling technique to uncover the latent network structure. We use a simulated biological reactor dataset in normal and faulty operation to validate our method. The method is general and can be used to analyze several different systems.