Hydrodynamics of a turbulent slot jet flow impinging on a concave surface

This study investigates hydrodynamic characteristics of a slot jet flow impinging on a concave surface experimentally and numerically. Six different concave plates with varying surface curvature and a flat plate are used. Air is used as the impinging coolant. In the experimental work, the slot nozzle used was specially designed with a sixth degree polynomial in order to provide a uniform velocity profile at its exit. The experiments were carried out for the jet Reynolds numbers in the range of 3000 < Re < 12500, the dimensionless nozzle-to-surface distance range of 1 ≤ H/W ≤ 14 for dimensionless value of the curvature of impinging surfaces in the range of R/L = 0.5, 0.5125, 0.566, 0.725, and 1.3. The pressure coefficient, C_p, for each test case was obtained across dimensionless arc length, s/W. Numerical computations were performed by using the k-ε turbulence model with enhanced wall functions for the concave plate with R/L = 0.725 and for the flat plate. The numerical results showed a reasonable agreement with the experimental data.     

Conductive Polymer-Coated 3D Printed Microneedles: Biocompatible Platforms for Minimally Invasive Biosensing Interfaces

Conductive polymeric microneedle (MN) arrays as biointerface materials show promise for the minimally invasive monitoring of analytes in biodevices and wearables. There is increasing interest in microneedles as electrodes for biosensing, but efforts have been limited to metallic substrates, which lack biological stability and are associated with high manufacturing costs and laborious fabrication methods, which create translational barriers. In this work, additive manufacturing, which provides the user with design flexibility and upscale manufacturing, is employed to fabricate acrylic-based microneedle devices. These microneedle devices are used as platforms to produce intrinsically-conductive, polymer-based surfaces based on polypyrrole (PPy) and poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS). These entirely polymer-based solid microneedle arrays act as dry conductive electrodes while omitting the requirement of a metallic seed layer. Two distinct coating methods of 3D-printed solid microneedles, in situ polymerization and drop casting, enable conductive functionality. The microneedle arrays penetrate ex vivo porcine skin grafts without compromising conductivity or microneedle morphology and demonstrate coating durability over multiple penetration cycles. The non-cytotoxic nature of the conductive microneedles is evaluated using human fibroblast cells. The proposed fabrication strategy offers a compelling approach to manufacturing polymer-based conductive microneedle surfaces that can be further exploited as platforms for biosensing.     

Lot Splitting Under Learning Effects with Minimal Revenue Requirements and Multiple Lot Types

The lot splitting problem in the presence of learning is addressed. This work is an extension of an approach proposed for splitting in the case of a single item. We address the issue of a minimal revenue requirement from partial deliveries until a predetermined time. This is achieved by imposing a constraint on what is originally an unconstrained optimization problem. When sublots of different items are involved, the optimal splitting decisions have to be combined with the sequencing of the deliveries. Numerical examples are presented to demonstrate the proposed approach.     

Polyphenol-modified glassy carbon electrodes for copper detection

The present work reports the preparation of electrochemically polymerized flavone - luteolin and flavonol - kaempferol modified glassy carbon (GC) electrodes (PolyLut/GC and PolyKae/GC, respectively). Electrochemical polymerization was performed by electrochemical oxidation of luteolin and kaempferol by potential cycling in aqueous media. Cyclic voltammograms of luteolin on the GC electrode indicated one clear oxidation peak at +475 mV, which can be assigned to the oxidation of 3′-hydroxyl and 4′-hydroxyl groups in the B-ring of the luteolin molecule. The cyclic voltammograms of kaempferol on the GC electrode contained two oxidation peaks, one at about +390 mV, which is assigned to the oxidation of 4′-hydroxyl and 3-hydroxyl groups of the B-ring and C-ring of the kaempferol molecule, and second oxidation peak at about +710 mV, which is assigned to the 7-hydroxyl group of the A-ring. The interaction of PolyLut/GC and PolyKae/GC electrodes with copper(II) (Cu(II)) ions were investigated by differential pulse voltammetry (DPV). It was determined that PolyLut/GC and PolyKae/GC electrodes showed sensitivity towards Cu(II) with good reproducibility and stability of analytical signal. The effect of the interfering ions on the voltammetric measurements of Cu(II) was examined.     

An early split and skip algorithm for fast intra CU selection in HEVC

The rapid development and increase of multimedia applications, as well as the demand for higher video-quality services at restricted resources such as storage capacity, transmission bandwidth and power consumption, has brought the urgent need for more efficient video compression techniques. The new video coding standard high efficiency video coding (HEVC) has a significant superiority over its predecessor advanced video coding (AVC). HEVC is reported to halve the bit rate with the same visual quality, or a better quality with the same bit rate when compared with AVC. Beside other improvements, HEVC significantly gets its power from the use of dynamic hierarchical quad-tree structure by partitioning the frames into smaller regions called coding units (CU), by means of a rate–distortion optimization process. However, this improvement yields to a dramatic increase of high computational complexity and increased encoding time, which primarily restricts its adaptation in real-time applications. In this paper, we proposed an early CU determination algorithm for fast encoder realization to reduce the encoding time which is the most important part of the standard standing for development. The experimental results show that the proposed algorithm has approximately 45 % encoding time saving with a 4.6 % bit-rate increment, on average.     

Unraveling Thermal and Dynamical Properties of the Cubic $$\mathrm{BaVO}_3$$ Perovskite from First-Principles Calculation

Using a toolkit of theoretical techniques comprising ab initio density functional theory calculations and quasiharmonic approximation, we investigate temperature dependence of dynamical properties of \(\mathrm{BaVO}_3\) perovskite. This interest is triggered by the fact that, recently, it was possible to synthesize a \(\mathrm{BaVO}_3\) perovskite, in a cubic phase, at high pressure and temperature. First-principle calculations are achieved thanks to recent development in numerical facilities, especially phonon dispersion curves which are then fully obtained. Elastic constants of the compound are dependent on temperature due to the inevitable anharmonic effects in solids. We show that at low temperature, the full account of the thermal effects incorporating the phonon densities and Sommerfeld model is more appropriate to calculate the thermal properties of a metal.     

Corner validation based on extracted corner properties

We developed a method to validate and filter a large set of previously obtained corner points. We derived the necessary relationships between image derivatives and estimates of corner angle, orientation and contrast. Commonly used cornerness measures of the auto-correlation matrix estimates of image derivatives are expressed in terms of these estimated corner properties. A candidate corner is validated if the cornerness score directly obtained from the image is sufficiently close to the cornerness score for an ideal corner with the estimated orientation, angle and contrast. We tested this algorithm on both real and synthetic images and observed that this procedure significantly improves the corner detection rates based on human evaluations. We tested the accuracy of our corner property estimates under various noise conditions. Extracted corner properties can also be used for tasks like feature point matching, object recognition and pose estimation.     

Immunohistochemical distribution of heat shock protein 70 and proliferating cell nuclear antigen in mouse placenta at different gestational stages

The aim of the present study was to investigate immunohistochemical distribution of heat shock protein 70 (Hsp70) and proliferating cell nuclear antigen (PCNA) in the mouse placenta at different gestational stages. For this purpose a total of 18 Swiss albino female mice at 12–14 weeks of age were used. Females were sacrificed on days 3 (early), 10 (mid‐), and 17 (late) of pregnancy and the implantation sites of the pregnant uterus were sampled. The sections were made transversely through the central region of the implantation site and stained with hematoxylin and eosin for histological examination. PCNA and Hsp70 was stained immunohistochemically. Since the definitive placenta was not still formed on day 3 of pregnancy, Hsp70 and PCNA positivity were evaluated in only luminal epithelium and decidual‐stromal cells. On days 10 and 17 of pregnancy, Hsp70 and PCNA positivity were evaluated in labyrinth zone, junctional zone and decidual layer of placenta. Hsp70 expression was observed trophoblast cells and decidual cells and was relatively constant throughout the pregnancy. This protein was strongly labeled in the trophoblast cells; while decidual cells were displayed moderate staining. In early pregnant mouse uteri, PCNA was mainly localized in decidual‐stromal cells. The trophoblast cells and decidual cells displayed highly proliferative activity at the midgestational period. However there was a significant decrease in the percentage of PCNA positive cells in late gestation. Microsc. Res. Tech. 79:251–257, 2016. © 2016 Wiley Periodicals, Inc.