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Abstract Growth control of cubic perovskite structure strontium titanate (SrTiO 3) thin films was facilely achieved by tailoring surface morphologies of the TiN seeding layer in the hydrothermal-galvanic couple (HT-GC) synthesis. Two types of TiN thin films with pyramidal (P-TiN) and granular (G-TiN) surface morphologies were deposited on Si substrates by sputtering. The TiN-coated Si working electrodes were then directly connected to the Pt counter electrode without applying any external power source and soaked in 0.1 M Sr(CH 3 COOH) 2 mixed with 2 M NaOH at 80 °C for 1–60 min. Significant galvanic currents were detected during the HT-GC synthesis. Directional oriented cubic SrTiO 3 thin films grew over the two types of highly preferred oriented TiN seeding layers. The growth kinetics of SrTiO 3 was deduced by fitting the coverage of the oxide over the two types of TiN at different reaction times to a modified Avrami equation. It was shown that galvanic currents, relative peak integrated intensities, and growth rates of SrTiO 3 over the P-TiN were much higher than those on the G-TiN, while the grain sizes of SrTiO 3 over the P-TiN were smaller. The faceted surfaces with fewer phase boundaries for P-TiN could yield a different rate-limiting step during the HT-GC synthesis and enhance significantly the growth of the oxide. This facile growth control could also be applied to similar perovskite oxide/conductive nitride systems. Highlights • SrTiO 3 was made on TiN-coated electrodes by the hydrothermal-galvanic couple method. • Directionally oriented SrTiO 3 thin films grew over highly preferred oriented TiN. • Growth kinetics of SrTiO 3 films was governed by tailoring surface morphology of TiN. • Different morphologies of TiN yield different growth rates and gain sizes of SrTiO 3. [ABSTRACT FROM AUTHOR]

Water availability, resulting from either a lack of water or poor water quality is a key factor contributing to regional water stress. This study proposes a set of sector-wise characterization factors (CFs), namely consumptive and degradative water stresses, to assess the impact of water withdrawals with a life cycle assessment approach. These CFs consider water availability, water quality, and competition for water between domestic, agricultural and industrial sectors and ecosystem at the watershed level. CFs were applied to a case study of regional water management of industrial water withdrawals in Taiwan to show that both regional or seasonal decrease in water availability contributes to a high consumptive water stress, whereas water scarcity due to degraded water quality not meeting sector standards has little influence on increased degradative water stress. Degradative water stress was observed more in the agricultural sector than in the industrial sector, which implies that the agriculture sector may have water quality concerns. Reducing water intensity and alleviating regional scale water stresses of watersheds are suggested as approaches to decrease the impact of both consumptive and degradative water use. The results from this study may enable a more detailed sector-wise analysis of water stress and influence water resource management policies. [ABSTRACT FROM AUTHOR]

Highlights: [•] Orthorhombic ZrTiO4 and amorphous Yb2O3 were confirmed by XRD and TEM. [•] Gate stack of ZrTiO4/Yb2O3 shows low D it and a small fixed oxide charge density. [•] MOSFETs with 0.79-nm EOT and excellent sub-Vt swing of 66mV/dec were realized. [•] Good reliability is proven by negligible ΔVt, Δgm and sub-Vt swing degradation. [Copyright &y& Elsevier]

Highlights: [•] Investigate the impact of dielectric crystallinity on the performance of RRAM. [•] Provides more insights into the different conduction mechanisms for RRAM operation. [•] Amorphous ZrTiO x outperforms crystalline ZrTiO x for RRAM applications. [Copyright &y& Elsevier]

Abstract: Advances in amphiphilic copolymers can potentially be exploited in drug or gene delivery. This study develops novel comb-like amphiphilic copolymers that comprise poly(γ-glutamic acid) (γ-PGA) as a hydrophilic backbone and Doxifluridine–poly-(ɛ-caprolactone) (5′-deoxy-5-fluorouridine–poly(ɛ-caprolactone), 5′DFUR–PCL) as a hydrophobic side chain. A novel 5′DFUR–PCL polymer was synthesized with antitumor agent Doxifluridine (5′DFUR) as the initiator via the ring-opening polymerization of ɛ-caprolactone (ɛ-CL) using tin(II) 2-ethylhexanoate (Sn(Oct)2) as the catalyst. The 5′DFUR–PCL polymer was then grafted on γ-PGA to yield a 5′DFUR–PCL–γ-PGA comb-like copolymer with the help of 1-ethyl-3-(3-dimethyl-aminopropyl) carbodiimide (EDC). The characteristics of these copolymers were examined by 1H NMR, FT-IR, GPC, contact angle measurement and thermal properties. Grafting 5′DFUR–PCL would significantly increase the contact angle and decrease the melting temperature (T m) of the copolymers. The micelles self-assembled from these amphiphilic copolymers were formed in an aqueous phase and were examined via fluorescence approaches, dynamic light scattering (DLS) and transmission electron microscopy (TEM). The average sizes of the micelles were in the range from 130 to 230nm and their zeta potentials were negative and less than −16.7mV. The critical micelle concentration (CMC) was from 1.49mg/L to 4.63mg/L at 25°C. TEM images demonstrated that the micelles were spherical and clearly had a core–shell structure. [Copyright &y& Elsevier]

Background/purpose: First-pass effect has been an important concern for oral pharmaceuticals. An in vivo system was developed for measuring different concentrations of pharmaceuticals in the portal vein and hepatic vein (via the inferior vena cava) for delineating presystemic metabolism under different perfusion rates by using indinavir as an exemplary agent.Methods: An in situ single-pass intestinal perfusion technique was modified from previous studies to concomitantly obtain portal and hepatic venous bloods. Portal and hepatic venous samples were simultaneously taken from rats at appropriate time points using the perfusion model of 1 mg/mL indinavir at flow rates of 0.05, 0.1, 0.5 and 1.0 mL/min. The indinavir concentrations were assayed by binary-gradient high-pressure liquid chromatography with UV detection.Results: The mean indinavir concentrations in portal vein concentration-time profiles at different perfusion times under various flow rates were all higher than those obtained for hepatic veins. At flow rates of 0.5 and 1.0 mL/min, in particular, the area under the curve (AUC) and maximal concentration (Cmax) of indinavir absorption were significantly different between portal veins and hepatic veins (p < 0.05), indicating considerable hepatic involvement in the presystemic extraction of indinavir. The system also has potential for use when estimating the hepatic extraction ratio (E(H)) and hepatic clearance (Cl(H)).Conclusion: This in vivo approach could provide another useful tool for improving our basic understanding of the absorption kinetics and hepatic metabolism of pharmaceuticals under development and facilitating the clinical application of such. [ABSTRACT FROM AUTHOR]

Skyline points and queries are important in the context of processing datasets with multiple dimensions. As skyline points can be viewed as representing marketable products that are useful for clients and business owners, one may also consider non-skyline points that are highly competitive with the current skyline points. We address the problem of continuously finding such potential products from a dynamic d -dimensional dataset, and formally define a potential product and its upgrade promotion cost. In this paper, we propose the CP-Sky algorithm, an efficient approach for continuously evaluating potential products by utilizing a second-order skyline set, which consists of candidate points that are closest to regular skyline points (also termed the first-order skyline set), to facilitate efficient computations and updates for potential products. With the knowledge of the second-order skyline set, CP-Sky enables the system to (1) efficiently find substitute skyline points from the second-order skyline set only if a first-order skyline point is removed, and (2) continuously retrieve the top- k potential products. Within this context, the Approximate Exclusive Dominance Region algorithm ( AEDR ) is proposed to reduce the computational complexity of determining a candidate set for second-order skyline updates over a dynamic data set without affecting the result accuracy. Additionally, we extend the CP-Sky algorithm to support the computations of top- k potential products. Finally, we present experimental results on data sets with various distributions to demonstrate the performance and utility of our approach. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we proposed a novel adjustable data hiding method. Our proposed method, which is based on exploiting modification direction (EMD) method, is called the “multi-group exploiting modification direction” method. In the multi-group method, we combine several pixel-groups to embed secret data according to the constructed switch map to simply avoid the conversion redundancy of the EMD method and the spatial redundancy of the section-wise strategy, as well as to efficiently increase the probability of achieving larger embedding capacity. According to the experimental results and mathematical justification, we verified that the multi-group method can achieve higher embedding payload and better visual quality of the image than the EMD method and section-wise strategy for simulated and real secret data. [Copyright &y& Elsevier]

Abstract: A Ge-stabilized tetragonal ZrO2 (t-ZrO2) film with permittivity (κ) of 36.2 was formed by depositing a ZrO2/Ge/ZrO2 laminate and a subsequent annealing at 600°C, which is a more reliable approach to control the incorporated amount of Ge in ZrO2. On Si substrates, with thin SiON as an interfacial layer, the SiON/t-ZrO2 gate stack with equivalent oxide thickness (EOT) of 1.75nm shows tiny amount of hysteresis and negligible frequency dispersion in capacitance–voltage (C–V) characteristics. By passivating leaky channels derived from grain boundaries with NH3 plasma, good leakage current of 4.8×10−8 A/cm2 at V g = V fb −1V is achieved and desirable reliability confirmed by positive bias temperature instability (PBTI) test is also obtained. [Copyright &y& Elsevier]