Low-frequency still-air acoustic inertia of inclined circular aperture in an infinite flat plate of finite thickness

The acoustic inertia of the canonical configuration of inclined circular aperture(s) in a finite-thickness plate at the low frequency limit is investigated under the inviscid still-air condition. A hybrid approach combining modal expansion and boundary element method is applied to calculate the effective length of the aperture as a quantitative characterisation of its acoustic inertia. These calculations, covering different inclination angles up to 75°, are performed for a single isolated aperture with a selected range of plate thickness and the periodic aperture arrays of aligned and staggered arrangements with a selected range of aperture spacing respectively. The results are validated by the simulations carried out with the commercial software COMSOL. The parametric studies of geometric dimensions included in this work provide representative results for typical acoustic related engineering applications of finite-length inclined apertures. A link for access to the MATLAB programmes implementing the calculations is provided for interested readers. As an example of application, the hybrid method described in this work is used for the acoustic modelling of a representative multi-perforated liner studied in the literature for the problem of thermo-acoustic instability. The results compared well against those obtained from the Computational Fluid Dynamics simulations reported in the literature.</p

Effects of tertiapin-Q (TQ) on the effect of ET-1 on spontaneous APs and ET-1 activated current.

<p>A. Continuous recording of spontaneous activity in control, in the presence of TQ (300 nM) before and with application of 10 nM ET-1 in the maintained presence of TQ. Note the absence of immediate hyperpolarisation and cessation of APs evident in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0033448#pone-0033448-g001" target="_blank">Figure 1</a>. Bi, ii and iii show expanded records from recording in A, at time-points indicated: i taken during control, ii near the end of TQ alone and iii is taken at ∼13 seconds of ET-1 application (at which time-point cells exposed to ET-1 alone had hyperpolarised and become quiescent). Similar results were obtained from 7 cells. C. Mean I–V relationships for the 10 nM ET-1 activated instantaneous current in absence (filled triangles, n = 14) and in presence of 300 nM TQ (open triangles, n = 7. except at −80 mV where n = 6). TQ prevented this action of ET-1. Asterisks in C denote statistical significance (p<0.05 *, p<0.001 ***).</p

ET-1 effects on the hyperpolarisation-activated current I_f.

<p>A. Upper traces show currents elicited −120 mV in an I_f-expressing cell in control solution and 10 nM ET-1 by protocol shown in bottom trace. Note outward shift in holding current in presence of ET-1. Closed circles indicate control trace; open circles indicate trace in ET-1. B. Mean I–V relationships (n = 7) for I_f, plotted as time-dependent current during command pulses, in absence (control, filled circles) and presence of 10 nM ET-1 (open circles). The activating effect of ET-1 was significant only at −120, −110 and −100 mV. C. Mean I–V relationships for the instantaneous current recorded at the beginning of the test-pulse (Ci: in absence (control, filled circles) and presence (open circles) of 10 nM ET-1). Cii shows I–V relation for the ET-1 activated instantaneous current (Cii, filled circles), in cells also showing I_f (n = 7). ET-1 activates a large inwardly rectifying current. D. I–V relations for I_f in presence of 1 µM BQ-123 (n = 11) without (filled squares) and with 10 nM ET-1 (open squares, n = 11 at all potentials except at −50 mV, where n = 10). BQ-123 prevented stimulation of I_f by ET-1. E. Inhibitory effect of 1 µM BQ-123 on the ET-1 activated current in cells exhibiting showing I_f (open squares, n = 12 except at −50 mV where n = 11). Asterisks denote statistical significance (p<0.001 ***).</p

Effects of ET-1 on spontaneous APs.

<p>A. Slow time-base recording of APs before, during and after rapid application of 10 nM ET-1. B. Expanded (faster time-base) portions of the recording extracted from numbered sections of panel A (indicated labels i, ii, iii). Similar results were observed in 9 experiments.</p

Effects of ET-1 on rapid delayed rectifier K⁺ current tails.

<p>A. Upper traces show currents elicited on depolarisation to +30 mV and subsequent repolarization to −40 mV by protocol shown in lower trace. Deactivating tail currents on repolarization represent the I_Kr ‘tail’. Currents are shown in control solution and in presence of 10 nM ET-1. Insert shows an expanded portion of the traces to highlight the ‘tail’ currents (the horizontal arrow in the inset denotes the zero current level). B. Mean ‘tail’ current I–V relationships for 5 cells, in absence (control, filled circles) and presence (open circles) of 10 nM ET-1. I–V curves were fitted with equation 2 (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0033448#s2" target="_blank">Methods</a>) to derive V_0.5 values of −15.7±3.6 mV in control and −0.7±4.3 mV in ET-1 (p<0.05), with respective k values of 6.4±2.6 mV and 6.9±3.9 mV (p>0.9). The ‘tail’ current was significantly reduced in presence of ET-1 at all voltages ranging from −20 to +50 mV except +20 mV. C. Mean I–V plots for I_Kr tails in the presence of 1 µM BQ-123 without (filled squares; n = 5) and with 10 nM ET-1 (open squares, n = 5 for all, except at +40 and +50 mV where n = 4). Derived V_0.5 values were −12.0±5.1 mV and −2.9±6.4 mV for BQ-123 and BQ-123+ET-1, respectively (P>0.3), with associated k values of 4.9±4.4 and 8.4±5.8 (p>0.6). Asterisks in B denote statistical significance (p<0.05 *, p<0.01 **, p<0.001 ***).</p

Modulation by ET-1 of instantaneous current in cells lacking I_f.

<p>Ai. Currents recorded in the absence (control) and the presence of 10 nM ET at −120 mV (upper traces) when a voltage command was applied from −40 mV for 500 ms (lower trace). Note outward shift in holding current with ET-1. Closed circles indicate control trace; open circles indicate trace in ET-1. Aii. ET-1 activated currents (elicited at −90, −100 and −120 mV) obtained by digital subtraction of control from ET-1 records (same cell as Ai). B. Mean current-voltage (I–V) relationships for current measured at the start of applied voltage commands in absence (control, filled circles) and presence (open circles) of 10 nM ET-1 (n = 7). Asterisks denote statistical significance (p<0.05 *, p<0.01 **, p<0.001 ***). C. Plot of the mean I–V relationship for ET-1 sensitive difference (ET-1 activated) calculated from the same cells shown in B. D. Plot of ET-1 sensitive current when ET-1 was applied after 1 µM BQ-123 (n = 4).</p

Manipulating Zn Metal Texture with Guided Zincophilic Sites via Electrochemical Stripping for Dendrite-Free Zn Anodes

Constructing a three-dimensional (3D) structure along with Zn (002) texture selective exposure is a promising strategy to tackle the issues faced by Zn metal anodes. Herein, for the first time, we proposed an electrochemical stripping strategy to achieve controlled modification of the texture and microstructure of zinc foils in one step, building a hierarchical structure with (002) texture preferred exposed Zn (SZ). The SZ with favorable zincophilic properties not only can reduce the concentration polarization at the interface but also allow Zn to grow horizontally on the edge of the (002) texture by guiding the adsorption sites for Zn2+. Moreover, the honeycomb-like structure is beneficial to rearrange the distribution of the Zn2+ flux as well as alleviating stress changes during cycling. Thus, the SZ||Cu cell exhibits excellent stability with a Coulombic efficiency of 99.76% over 1800 cycles. The SZ||NaV3O8·xH2O cell with inconspicuous self-discharge effect maintains a high areal capacity of 3.67 mA h cm–2 even after 700 cycles with a low N/P ratio of 3.6. This work achieves texture architecture and structure designing on Zn foils simultaneously by metallurgical electrochemical methods and opens up a potential strategy to implement the practicality of zinc metal anodes

Hierarchically Self-Assembled Supramolecular Host–Guest Delivery System for Drug Resistant Cancer Therapy

In this report, a new star-like copolymer β-CD-<i>g</i>-(PNIPAAm-<i>b</i>-POEGA)_<i>x</i>, consisting of a β-CD core, grafted with temperature-responsive poly­(<i>N</i>-isopropylacrylamide) (PNIPAAm) and biocompatible poly­(oligo­(ethylene glycol) acrylate) (POEGA) in a block copolymer of the arms, was used to deliver chemotherapeutics to drug resistant cancer cells and tumors. The first step of the self-assembly process involves the encapsulation of chemotherapeutics through host–guest inclusion complexation between the β-cyclodextrin cavity and the anticancer drug. Next, the chain interaction of the PNIPAAm segment at elevated temperature drives the drug-loaded β-CD-<i>g</i>-(PNIPAAm-<i>b</i>-POEGA)_<i>x</i>/PTX inclusion complex to hierarchically self-assemble into nanosized supramolecular assemblies at 37 °C, whereas the presence of poly­(ethylene glycol) (PEG) chains in the distal end of the star-like copolymer arms impart enhanced stability to the self-assembled structure. More interestingly, this supramolecular host–guest nanocomplex promoted the enhanced cellular uptake of chemotherapeutics in MDR-1 up-regulated drug resistant cancer cells and exhibited high therapeutic efficacy for suppressing drug resistant tumor growth in an <i>in vivo</i> mouse model, due to the increased stability, improvement in aqueous solubility, enhanced cellular uptake, and partial membrane pump impairment by taking the advantage of PEGylation and supramolecular complex between this star-like copolymer and chemotherapeutics. This work signifies that temperature-sensitive PEGylated supramolecular nanocarriers with good biocompatibility are effective in combating MDR-1 mediated drug resistance in both <i>in vitro</i> and <i>in vivo</i> models, which is of significant importance for the advanced drug delivery platform designed to combat drug resistant cancer

Multinomial logistic regression analysis of the first ten coordinates based on Unifrac and weighted Unifrac distances.

<p>Multinomial logistic regression analysis of the first ten coordinates based on Unifrac and weighted Unifrac distances.</p

Measurements and comparisons of alpha diversity in esophageal squamous cell carcinoma (ESCC), dysplasia control and healthy control (Control) groups.

<p>Measurements and comparisons of alpha diversity in esophageal squamous cell carcinoma (ESCC), dysplasia control and healthy control (Control) groups.</p