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Combinations of semiconductor metal oxide (SMO) sensors, electrochemical (EC) sensors, and photoionization detection (PID) sensors were used to discriminate chemical hazards on the basis of machine learning. Sensing data inputs were exploited in the form of either numerical or image data formats, and the classification of chemical hazards with high accuracy was achieved in both cases. Even a small amount of gas sensing or purging data (input for ∼30 s) input can be exploited in machine-learning-based gas discrimination. SMO sensors exhibit high performance even in a single-sensor mode, presumably because of the intrinsic cross-sensitivity of metal oxides, which is otherwise considered a major disadvantage of SMO sensors. EC sensors were enhanced through synergistic integration of sensor combinations with machine learning. For precision detection of multiple target analytes, a minimum number of sensors can be proposed for gas detection/discrimination by combining sensors with dissimilar operating principles. The Type I hybrid sensor combines one SMO sensor, one EC sensor, and one PID sensor and is used to identify NH 3 gas mixed with sulfur compounds in simulations of NH 3 gas leak accidents in chemical plants. The portable remote sensing module made with a Type I hybrid sensor and LTE module can identify mixed NH 3 gas with a detection time of 60 s, demonstrating the potential of the proposed system to quickly respond to hazardous gas leak accidents and prevent additional damage to the environment., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

A high-performance semiconductor metal oxide gas sensing strategy is proposed for efficient sensor-based disease prediction by integrating a machine learning methodology with complementary sensor arrays composed of SnO 2 - and WO 3 -based sensors. The six sensors, including SnO 2 - and WO 3 -based sensors and neural network algorithms, were used to measure gas mixtures. The six constituent sensors were subjected to acetone and hydrogen environments to monitor the effect of diet and/or irritable bowel syndrome (IBS) under the interference of ethanol. The SnO 2 - and WO 3 -based sensors suffer from poor discrimination ability if sensors (a single sensor or multiple sensors) within the same group (SnO 2 - or WO 3 -based) are separately applied, even when deep learning is applied to enhance the sensing operation. However, hybrid integration is proven to be effective in discerning acetone from hydrogen even in a two-sensor configuration through the synergistic contribution of supervised learning, i.e., neural network approaches involving deep neural networks (DNNs) and convolutional neural networks (CNNs). DNN-based numeric data and CNN-based image data can be exploited for discriminating acetone and hydrogen, with the aim of predicting the status of an exercise-driven diet and IBS. The ramifications of the proposed hybrid sensor combinations and machine learning for the high-performance breath sensor domain are discussed.

This study was conducted to investigate the antimicrobial effects of 300 Asian plant extracts (PEs) against pathogenic and spoilage bacteria. The antimicrobial activities were examined using agar well or agar disc diffusion, and micro-titer methods. Results revealed that PEs exhibited higher antimicrobial effects against Gram-positive bacteria compared than against Gram-negative bacteria. With few exceptions, PEs delayed the lag time (LT) of pathogenic bacteria (1.17-3.75 times). Among PEs tested, Alchornea trewioides (AT) and Erodium stephanianum (ES) were the most effective in inhibiting pathogenic and spoilage bacteria. In the study evaluating the effect on the growth inhibition in the broth, Acetobacter aceti was inhibited at 2.77 and 3.02 log CFU/mL by the combination treatment of AT+nisin and ES+nisin after storage for 7 days, respectively. Although further investigations are needed to clarify the antimicrobial mechanism of PEs, this study demonstrated that antimicrobial efficacy varied with PE types, solvents, and bacteria., Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-022-01182-0., Competing Interests: Conflict of interestThe authors declare no conflicts of interest., (© The Korean Society of Food Science and Technology 2022, Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

Metal thin films have been widely used as conductors in semiconductor devices for several decades. However, the resistivity of metal thin films such as Cu and TiN increases substantially (>1000%) as they become thinner (<10 nm) when using high-density integration to improve device performance. In this study, the resistivities of MAX-phase V 2 AlC films grown on sapphire substrates exhibited a significantly weaker dependence on the film thickness than conventional metal films that resulted in a resistivity increase of only 30%, as the V 2 AlC film thickness decreased from approximately 45 to 5 nm. The resistivity was almost identical for film thicknesses of 10-50 nm. The small change in the resistivity of V 2 AlC films with decreasing film thickness originated from the highly ordered crystalline quality and a small electron mean free path (11-13.6 nm). Thus, MAX-phase thin films have great potential for advanced metal technology applications to overcome the current scaling limitations of semiconductor devices.

In this work, loess-based materials were designed based on a multicomponent composite materials system for ecofriendly natural three-dimensional (3D) printing involving quick lime, gypsum, and water. The 3D printing process was monitored as a function of gypsum content; in terms of mechanical strength and electrical resistance, in the cube-shaped bulk form. After initial optimization, the 3D printing composition was refined to provide improved printability in a 3D printing system. The optimal 3D fabrication allowed for reproducible printing of rectangular columns and cubes. The development of 3D printing materials was scrutinized using a multitude of physicochemical probing tools, including X-ray diffraction for phase identification, impedance spectroscopy to monitor setting behaviors, and mercury intrusion porosimetry to extract the pore structure of loess-based composite materials. Additionally, the setting behavior in the loess-based composite materials was analyzed by investigating the formation of gypsum hydrates induced by chemical reaction between quick lime and water. This setting reaction provides reasonable mechanical strength that is sufficient to print loess-based pastes via 3D printing. Such mechanical strength allows utilization of robotic 3D printing applications that can be used to fabricate ecofriendly structures.

Responsive materials designed to generate signals for both surface-enhanced Raman spectroscopy (SERS) and phosphorescence lifetime-"dual-mode"-measurements are described. To demonstrate this concept, we incorporated pH-sensitive and oxygen-sensitive microdomains into a single hydrogel that could be interrogated via SERS and phosphorescence lifetime, respectively. Microdomains consisted two populations of discrete microcapsules containing either (1) gold nanoparticles capped with pH-sensitive Raman molecules or (2) oxygen-sensitive benzoporphyrin phosphors. While the microdomain-embedded hydrogels presented an expected background luminescence, the pH-sensitive SERS signal was distinguishable for all tested conditions. Response characteristics of the dual sensor showed no significant difference when compared to standalone single-mode pH and oxygen sensors. In addition, the feasibility of redundant multimode sensing was proven by observing the reaction produced by glucose oxidase chemically cross-linked within the corresponding alginate matrix. Each optical mode showed a signal change proportional to glucose concentration with an opposite signal directionality. These results support the promise of micro-/nanocomposite materials to improve measurement accuracy using intrinsic multimode responses and built-in redundancy, concepts that have broad appeal in the chemical sensing and biosensing fields.

This study investigated the pull-out resistance of superelastic shape memory alloy (SMA) short fibers in mortar with consideration of various end-anchorages that provide different anchoring actions. For the purpose, four types of SMA fibers were prepared using NiTi SMA wires with a diameter of 1.0 mm and the following four end shapes: straight (ST), L-shaped (LS), N-shaped (NS), and spearhead-shaped (SH). The straight-ended fiber was a reference with no working on the end, and the fiber with the spearhead-shaped end was crimped to make the end part flat. The fibers with L- and N-shaped ends were bent with single or double bending. The results showed that only the spearhead-shaped fibers showed self-centering behavior because of the superelasticity of the SMA after slip occurred. This paper discusses the reasons that the ST, LS, and NS fibers do not show self-centering behavior and proposes a concept to induce superelastic behavior in SMA fibers in mortar or concrete.

To date, most of the studies on quantum dot-light-emitting diodes (QLEDs) have been dedicated to the fabrication of high-efficiency monochromatic devices. However, for the ultimate application of QLEDs to the next-generation display devices, QLEDs should possess a full-color emissivity. In this study, we report the fabrication of all-solution-processed full-color-capable white QLEDs with a standard device architecture, where sequentially stacked blue (B)/green (G)/red (R) quantum dot (QD)-emitting layers (EMLs) are sandwiched by poly(9-vinylcarbazole) as the hole transport layer and ZnO nanoparticles (NPs) as the electron transport layer. To produce interlayer mixing-free, well-defined B/G/R QD layering assemblies via successive spin casting, an ultrathin ZnO NP buffer is inserted between different-colored QD layers. The present full-color-capable white QLED exhibits high device performance with the maximum values of 16 241 cd m-2 for luminance and 6.8% for external quantum efficiency. The promising results indicate that our novel EML design of ZnO NP buffer-mediated QD layer stacking may afford a viable means towards bright, efficient full-color-capable white devices.

Self-healing is an essential property of smart concrete structures. In contrast to other structural metals, shape memory alloys (SMAs) offer two unique effects: shape memory effects, and superelastic effects. Composites composed of SMA wires and conventional cements can overcome the mechanical weaknesses associated with tensile fractures in conventional concretes. Under specialized environments, the material interface between the cementitious component and the SMA materials plays an important role in achieving the enhanced mechanical performance and robustness of the SMA/cement interface. This material interface is traditionally evaluated in terms of mechanical aspects, i.e., strain-stress characteristics. However, the current work attempts to simultaneously characterize the mechanical load-displacement relationships synchronized with impedance spectroscopy as a function of displacement. Frequency-dependent impedance spectroscopy is tested as an in situ monitoring tool for structural variations in smart composites composed of non-conducting cementitious materials and conducting metals. The artificial geometry change in the SMA wires is associated with an improved anchoring action that is compatible with the smallest variation in resistance compared with prismatic SMA wires embedded into a cement matrix. The significant increase in resistance is interpreted to be associated with the slip of the SMA fibers following the elastic deformation and the debonding of the SMA fiber/matrix., Competing Interests: The authors declare no conflicts of interest.

Electrodes composed of multilayered graphene grown on a metal foam (GMF) were prepared by directly growing multilayer graphene sheets on a three-dimensional (3D) Ni-foam substrate via a self-catalyzing chemical vapor deposition process. The multilayer graphene sheets are successfully grown on the Ni-foam substrate surface, maintaining the unique 3D macroporous structure of the Ni foam. The potential use of GMF electrodes in nonaqueous redox flow batteries (RFBs) is carefully examined using [Co(bpy) 3 ] +/2+ and [Fe(bpy) 3 ] 2+/3+ redox couples. The GMF electrodes display a much improved electrochemical activity and enhanced kinetics toward the [Co(bpy) 3 ] +/2+ (anolyte) and [Fe(bpy) 3 ] 2+/3+ (catholyte) redox couples, compared with the bare Ni metal foam electrodes, suggesting that the 2D graphene sheets having lots of interdomain defects provide sufficient reaction sites and secure electric-conduction pathways. Consequently, a nonaqueous RFB cell assembled with GMF electrodes exhibits high Coulombic and voltage efficiencies of 87.2 and 90.9%, respectively, at the first cycle. This performance can be maintained up to the 50th cycle without significant efficiency loss. Moreover, the importance of a rational electrode design for improving electrochemical performance is addressed.

Ischemic stroke and cardiovascular disease can occur from blockage of blood vessels by fibrin clots formed naturally in the body. Therapeutic drugs of anticoagulant or thrombolytic agents have been studied; however, various problems have been reported such as side effects and low efficacy. Thus, development of new candidates that are more effective and safe is necessary. The objective of this study is to evaluate fibrinolytic activity, anti-coagulation, and characterization of serine protease purified from Lumbrineris nipponica, polychaeta, for new thrombolytic agents. In the present study, we isolated and identified a new fibrinolytic serine protease from L. nipponica. The N-terminal sequence of the identified serine protease was EAMMDLADQLEQSLN, which is not homologous with any known serine protease. The size of the purified serine protease was 28 kDa, and the protein purification yield was 12.7%. The optimal enzyme activity was observed at 50°C and pH 2.0. A fibrin plate assay confirmed that indirect fibrinolytic activity of the purified serine protease was higher than that of urokinase-PA, whereas direct fibrinolytic activity, which causes bleeding side effects, was relatively low. The serine protease did not induce any cytotoxicity toward the endothelial cell line. In addition, anticoagulant activity was verified by an in vivo DVT animal model system. These results suggest that serine protease purified from L. nipponica has the potential to be an alternative fibrinolytic agent for the treatment of thrombosis and use in various biomedical applications.

The effectiveness of sanitizing treatments was investigated on reducing pathogens inoculated in whole or cut fresh vegetables, including Brussels sprouts, carrots, cherry tomatoes, paprika, and lettuce. These products were inoculated with Escherichia coli O157:H7, Salmonella enterica serovar Typhimurium, and Listeria monocytogenes and then treated with chlorine and alcohol sanitizers, followed by the subsequent washing procedure in sterile distilled water at 25°C for 5min. Alcohol sanitizer was the most effective in inhibiting E. coli O157:H7, S. Typhimurium, and L. monocytogenes on cut Brussels sprouts, showing bacterial reductions of 4.16, 3.60, and 3.26 log CFU/g, respectively. Interestingly, the effects of sanitizing treatments were significantly lower for fresh cut produce than those for whole products ( p <0.05), indicating that the effectiveness of sanitizers would be different, depending on fresh produce and the pre-cut process. Therefore, further information should be obtained to develop an effective sanitizing treatment for fresh produce.

A heteronemertean, Yininemertes pratensis , was collected in Han River Estuary, South Korea. This estuarine nemertean has been known by the local fishermen for harmful effects to the glass eels, juveniles of Japanese eel Anguilla japonica , migrating to fresh water. The present study confirmed the neurotoxic effects of this heteronemertean ribbon worm at the cellular level. Derivative types of neurotoxic tetrodotoxin (TTX), 5,11-dideoxy TTX ( m/z 288) and 11-norTTX-6(S)-01 ( m/z 305.97), were identified through HPLC and MALDI-TOF MS. However, significant neurotoxicity was confirmed in the fraction containing an undefined molecule corresponding to the 291.1 ( m/z ) peak, when tested in rat primary astrocytes and dorsal ganglion cells. This study is the first to report neurotoxins of the estuarine nemertean, fairly abundant in the Han River estuary, and suggests the long-term monitoring of population dynamics and surveillance of the toxicity in this river estuary.

In Southeast Asian countries, including Korea, China, and Japan, the considerable amounts of raw fish have been annually consumed in the manner of live fish fillets without minimally thermal processing, increasing the risks of causing food-borne diseases. This study investigated the occurrence of total aerobic bacteria (TAB), coliform, Vibrio parahaemolyticus , Salmonella enterica serovar spp., Listeria monocytogenes , and Staphylococcus aureus in jacopevers and plaices. Total 200 live fishes were collected from randomly selected restaurants located in Anseong-si, and then they were microbiologically monitored. TAB ranged from 3.09 to 3.21 Log 10 CFU/g in jacopever and plaice. Coliform in the levels of 1.54 Log 10 CFU/g were detected in samples. Out of 100 jacopevers, a single jacopever (1%) exhibited the prevalence of S. aureus in the edible part, though none of pathogenic bacteria were detected. These results will be useful for understanding the microbial prevalence in the domestic living jacopevers and plaices.

This study investigated biofilm formation, cell surface hydrophobicity, colony spreading, and slime production for 112 Staphylococcus aureus strains isolated from various sources (leaf vegetables, pea leaf, perilla leaf, Kim-bab , person, and animal). When biofilm formation was classified by origin, S. aureus isolated from animal origin showed a significantly higher level of biofilm formation than others ( p ≤0.05). When S. aureus groups with different levels of biofilm formation (very strong, strong, moderate, and weak) were evaluated for the correlation with cell surface properties, there was a positive correlation between biofilm formation and hydrophobicity ( r =0.926). Biofilm formation and colony spreading on tryptic soy broth (without dextrose) also showed positive correlation ( r =0.863). In contrast, biofilm formation and slime production were negatively correlated ( r =-0.973). Based on these results, the biofilm forming ability of S. aureus differs depending on their origin and might be affected by cell surface properties such as cell surface hydrophobicity.

The layer-by-layer modification of ≈5 nm mercaptocarboxylic acid stabilized gold nanoparticles was studied in an effort to illustrate effective means to overcome practical issues in handling and performing surface modification of such extremely small materials. To accomplish this, each layer deposition cycle was separated into a multi-step process wherein solution pH was controlled in two distinct phases of polyelectrolyte adsorption and centrifugation. Additionally, a solvent precipitation step was introduced to make processing more amenable by concentrating the sample and exchanging solution pH before ultracentrifugation. The pH-dependent assembly on gold nanoparticles was assessed after each layer deposition cycle by monitoring the plasmon peak absorbance location, surface charge, and the percentage of nanoparticles recovered. The selection of solution pH during the adsorption phase was found to be a critical parameter to enhance particle recovery and maximize surface charge when coating with weak polyelectrolytes. One bilayer was deposited with a high yield and the modified particles exhibited enhanced colloidal stability across a broad pH range and increased ionic strength. These findings support the adoption of this multi-step processing approach as an effective and generalizable approach to improve stability of high surface curvature particles., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Atopic dermatitis (AD) is a complex skin disease primarily characterized by psoriasis of the stratum corneum. AD drugs have usually been used in acidic and hydrophilic solvents to supply moisture and prevent lipid defects. Ceramide is a typical treatment agent to regenerate the stratum corneum and relieve symptoms of AD. However, ceramide has limitation on direct use for skin because of its low dispersion properties in hydrophilic phase and side effects at excessive treatment. In this study, ceramide imbedded PLGA nanoparticles were developed with chitosan coating (Chi-PLGA/Cer) to overcome this problem. The chitosan coating enhanced initial adherence to the skin and prevented the initial burst of ceramide, but was degraded by the weakly acidic nature of skin, resulting in controlled release of ceramide with additional driving force of the squeezed PLGA nanoparticles. Additionally, the coating kinetics of chitosan were controlled by manipulating the reaction conditions and then mathematically modeled. The Chi-PLGA/Cer was not found to be cytotoxic and ceramide release was controlled by pH, temperature, and chitosan coating. Finally, Chi-PLGA/Cer was demonstrated to be effective at stratum corneum regeneration in a rat AD model. Overall, the results presented herein indicated that Chi-PLGA/Cer is a novel nanodrug for treatment of AD.

Relatively few recurrent gene fusion events have been associated with breast cancer to date. In an effort to uncover novel fusion transcripts, we performed whole-transcriptome sequencing of 120 fresh-frozen primary breast cancer samples and five adjacent normal breast tissues using the Illumina HiSeq2000 platform. Three different fusion-detecting tools (deFuse, Chimerascan, and TopHatFusion) were used, and the results were compared. These tools detected 3,831, 6,630 and 516 fusion transcripts (FTs) overall. We primarily focused on the results obtained using the deFuse software. More FTs were identified from HER2 subtype breast cancer samples than from the luminal or triple-negative subtypes (P < 0.05). Seventy fusion candidates were selected for validation, and 32 (45.7%) were confirmed by RT-PCR and Sanger sequencing. Of the validated fusions, six were recurrent (found in 2 or more samples), three were in-frame (PRDX1-AKR1A1, TACSTD2-OMA1, and C2CD2-TFF1) and three were off-frame (CEACAM7-CEACAM6, CYP4X1-CYP4Z2P, and EEF1DP3-FRY). Notably, the novel read-through fusion, EEF1DP3-FRY, was identified and validated in 6.7% (8/120) of the breast cancer samples. This off-frame fusion results in early truncation of the FRY gene, which plays a key role in the structural integrity during mitosis. Three previously reported fusions, PPP1R1B-STARD3, MFGE8-HAPL, and ETV6-NTRK3, were detected in 8.3, 3.3, and 0.8% of the 120 samples, respectively, by both deFuse and Chimerascan. The recently reported MAGI3-AKT3 fusion was not detected in our analysis. Although future work will be needed to examine the biological significance of our new findings, we identified a number of novel fusions and confirmed some previously reported fusions., (© 2015 Wiley Periodicals, Inc.)

Two-dimensional electron gas (2DEG) at the complex oxide interfaces have brought about considerable interest for the application of the next-generation multifunctional oxide electronics due to the exotic properties that do not exist in the bulk. In this study, we report the integration of 2DEG into the nonvolatile resistance switching cell as a bottom electrode, where the metal-insulator transition of 2DEG by an external field serves to significantly reduce the OFF-state leakage current while enhancing the on/off ratio. Using the Pt/Ta2O5-y/Ta2O5-x/SrTiO3 heterostructure as a model system, we demonstrate the nonvolatile resistance switching memory cell with a large on/off ratio (>10(6)) and a low leakage current at the OFF state (∼10(-13) A). Beyond exploring nonvolatile memory, our work also provides an excellent framework for exploring the fundamental understanding of novel physics in which electronic and ionic processes are coupled in the complex heterostructures.

Micro-contact printing of self-assembly monolayers (SAMs), i.e., octadecyl-trichlorosilane (OTS) was combined with self limiting atomic layer deposition in order to fabricate the selective deposition of nickel oxide on amorphous Si thin films. The localized nickel species facilitated metal-induced crystallization (MIC) and at later stages, metal-induced lateral crystallization (MILC) in amorphous Si thin films at the elevated temperatures ranging from 500 °C to 550 °C. The uniform coating of SAMs onto amorphous Si thin films was monitored using physical/chemical characterization, i.e., atomic force microscopy, electron microscopy, and Raman spectroscopy. The crystalline feature was found to be superior to the counterpart solid-phase crystallization. The effectiveness of SAMs appears to provide the microscale patterning in addition to the sophisticated control against nickel-species.

Recognizing that steel fibers can supplement the brittle tensile characteristics of concrete, many studies have been conducted on the shear performance of steel fiber reinforced concrete (SFRC) members. However, previous studies were mostly focused on the shear strength and proposed empirical shear strength equations based on their experimental results. Thus, this study attempts to estimate the strains and stresses in steel fibers by considering the detailed characteristics of steel fibers in SFRC members, from which more accurate estimation on the shear behavior and strength of SFRC members is possible, and the failure mode of steel fibers can be also identified. Four shear behavior models for SFRC members have been proposed, which have been modified from the softened truss models for reinforced concrete members, and they can estimate the contribution of steel fibers to the total shear strength of the SFRC member. The performances of all the models proposed in this study were also evaluated by a large number of test results. The contribution of steel fibers to the shear strength varied from 5% to 50% according to their amount, and the most optimized volume fraction of steel fibers was estimated as 1%-1.5%, in terms of shear performance.

Digital quantification of a two-dimensional structure was applied to a GDC(Gd₂O₃-doped CeO₂)/LSM(La₀.₈₅Sr₀.₁₅MnO₃) composite cathode employed for solid oxide fuel cells. With the aid of high-resolution imaging capability based on secondary and backscattered electron images, two-dimensional electron micrographs were converted to digital binary files using an image processing tool combined with the line intercept method. Statistical analysis combined with a metallurgical tool was employed to determine microstructural factors, i.e., volume fraction, size distribution, and interconnectivity. The current work reports the quantification of the two-dimensional structural images of GDC/LSM composites applicable to solid oxide fuel cells, with the aim of obtaining the volume fraction, size distribution, and interconnectivity as functions of composite composition. The volume fractions of the solid constituent phases exhibit compositional dependence in cathodes; however, LSM interconnectivity increases gradually as a function of LSM composition, whereas that of GDC decreases significantly at 50 wt% LSM.

P-type copper oxide nanowires (NWs) were grown on metallic copper plates and sapphire substrates. Significant variations in the morphology and distribution of the NWs, due to underlying differences in the growth mechanism and the NW densities, were observed based on the nature of the substrate utilized. The use of copper plates induced an extremely high density of copper oxide nanowires on temperature-dependent copper oxide layers. However, the sapphire substrates gave rise to highly superior CuO NWs without any involvement of an oxide layer, leading to a low density of copper oxide NWs. Systematic characterization of the as-grown copper oxide NWs using X-ray photoelectron microscopy and Raman spectroscopy indicated that the NWs were comprised of CuO with Cu2+ metallic ions.

Annotation of the recently sequenced genome of the pea aphid (Acyrthosiphon pisum) identified a gene ApAQP2 (ACYPI009194, Gene ID: 100168499) with homology to the Major Intrinsic Protein/aquaporin superfamily of membrane channel proteins. Phylogenetic analysis suggests that ApAQP2 is a member of an insect-specific clade of this superfamily. Homology model structures of ApAQP2 showed a novel array of amino acids comprising the substrate selectivity-determining "aromatic/arginine" region of the putative transport pore. Subsequent characterization of the transport properties of ApAQP2 upon expression in Xenopus oocytes supports an unusual substrate selectivity profile. Water permeability analyses show that the ApAQP2 protein exhibits a robust mercury-insensitive aquaporin activity. However unlike the water-specific ApAQP1 protein, ApAQP2 forms a multifunctional transport channel that shows a wide permeability profile to a range of linear polyols, including the potentially biologically relevant substrates glycerol, mannitol and sorbitol. Gene expression analysis indicates that ApAQP2 is highly expressed in the insect bacteriocytes (cells bearing the symbiotic bacteria Buchnera) and the fat body. Overall the results demonstrate that ApAQP2 is a novel insect aquaglyceroporin which may be involved in water and polyol transport in support of the Buchnera symbiosis and aphid osmoregulation., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Atomic layer deposition (ALD) of nickel oxide was applied to the nickel-induced crystallization of amorphous Si thin films. The nickel-induced crystallization was monitored as a function of annealing temperature and time using Raman spectroscopy. Since Raman spectroscopy allows for the numerical quantification of structural components, the incubation time and the crystallization rates were estimated as functions of the annealing temperature. The spatial locations of a nickel-based species, probably NiSi2, were investigated using X-ray photoelectron spectrometry. The formed NiSi2 seeds appeared to accelerate the crystallization kinetics in amorphous Si thin films deposited onto glass substrates. The ramifications of the atomic layer deposition are discussed with regard to large-panel displays, with special emphasis on the sophisticated control of the catalytic elements, especially nickel.

The nanolaminate Al2O3/Cu/Al2O3 structures were constructed on p-type Si (001) substrates using atomic layer deposition (ALD) process with the aim to fabricating nonvolatile charge-trap memories. Low temperature Cu thin layers were deposited through plasma-enhanced atomic layre depositon of Cu aminoalkoxide (Cu(dmamb)2) combined with hydrogen plasma and Al2O3 layers were prepared by thermal atomic layer deposition of trimethylaluminum (TMA) combined with H2O. Nonvolatile features were confirmed using capacitance-voltage (C-V) measurements. The copper film functions as a charge-trapping layer and the Al2O3 thin layers were employed as tunneling and control oxide layers. Line shapes and binding energies of Cu metal and the thin layer of 6 nm Cu in nanolaminate structures were observed in the X-ray photoelectron spectroscopy (XPS) and high resolution transmission electron microscopy (TEM) image. The V(FB) shift width of the Al2O3 (28 nm)/Cu (6 nm)/Al2O3 (4.2 nm)/Si laminate structure is found to be 4.75 V in voltage sweeping between -10 and +10 V, leading to the trap density of 1.68 x 10(18) cm(-3).

Soybean nodulin 26 (nod26), a member of the aquaporin superfamily, is the major protein component of the symbiosome membrane that encloses nitrogen-fixing bacteroids in root nodules. Previous work has demonstrated that nod26 facilitates the transport of water and glycerol, although a potential additional role as a channel for fixed ammonia efflux has been hypothesized. In the present study it is shown that recombinant nod26 reconstituted into proteoliposomes facilitates NH(3) transport in an Hg(2+)-sensitive manner with a reduced activation energy, hallmarks of protein-facilitated transport characteristic of aquaporins. Comparison of the predicted single-channel transport rates of nod26 suggests a 4.9-fold preference for ammonia compared to water., (Copyright © 2010 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.)

Nodulin 26 (nod26) is a major intrinsic protein that constitutes the major protein component on the symbiosome membrane (SM) of N(2)-fixing soybean nodules. Functionally, nod26 forms a low energy transport pathway for water, osmolytes, and NH(3) across the SM. Besides their transport functions, emerging evidence suggests that high concentrations of major intrinsic proteins on membranes provide interaction and docking targets for various cytosolic proteins. Here it is shown that the C-terminal domain peptide of nod26 interacts with a 40-kDa protein from soybean nodule extracts, which was identified as soybean cytosolic glutamine synthetase GS(1)beta1 by mass spectrometry. Fluorescence spectroscopy assays show that recombinant soybean GS(1)beta1 binds the nod26 C-terminal domain with a 1:1 stoichiometry (K(d) = 266 nm). GS(1)beta1 also binds to isolated SMs, and this binding can be blocked by preincubation with the C-terminal peptide of nod26. In vivo experiments using either a split ubiquitin yeast two-hybrid system or bimolecular fluorescence complementation show that the four cytosolic GS isoforms expressed in soybean nodules interact with full-length nod26. The binding of GS, the principal ammonia assimilatory enzyme, to the conserved C-terminal domain of nod26, a transporter of NH(3), is proposed to promote efficient assimilation of fixed nitrogen, as well as prevent potential ammonia toxicity, by localizing the enzyme to the cytosolic side of the symbiosome membrane.

There is a growing need for the large-scale identification of the ubiquitinated proteins and ubiquitin attachment sites. As part of this effort, we generated a transgenic mouse expressing a tagged ubiquitin in the heart. We found that the majority of ubiquitinated proteins in mouse heart are insoluble in detergent-free buffer and were chemically cleaved after methionine with CNBr. CNBr cleaved the proteins into smaller polypeptides while preserving the ubiquitin chains. Ubiquitin-conjugated polypeptides were then purified under denaturing conditions, digested with Lys-C and trypsin, and analyzed by liquid chromatography-tandem mass spectrometry. We identified 121 proteins that were ubiquitinated in mouse heart, and we detected 33 ubiquitination sites in 21 of the proteins. Components of cardiac muscle and many mitochondrial proteins were identified as substrates for ubiquitination, strongly suggesting that proteins related to major heart functions such as contraction and energy production are under continuous quality control by the ubiquitin system.

Amyloid-beta peptide 42 (Abeta42) mediates neuronal degeneration in Alzheimer's disease (AD). We sought to produce recombinant Abeta42 as an ubiquitin extension. A synthetic oligonucleotide encoding Abeta42 was constructed and cloned as an extended polypeptide of hexahistidine-tagged ubiquitin (H(6)Ub) using the pET vector. Isopropyl-beta-D-thiogalactopyranoside induction of transformed Escherichia coli resulted in the production of large amounts of insoluble H(6)Ub-Abeta42 fusion protein. H(6)Ub-Abeta42 was solubilized in 8 M urea and applied to a nickel-nitrilotriacetic acid affinity column for purification. Column washing removed the urea and soluble H(6)Ub-Abeta42 was eluted, indicating that covalently attached ubiquitin prevented Abeta42 from aggregating. Abeta42 was cleaved from H(6)Ub using recombinant yeast ubiquitin hydrolase-1 (YUH-1) and purified using reverse-phase chromatography. The recombinant Abeta42 prepared in this study has the same toxic effect on human neuroblastoma SH-SY5Y cells comparing with chemically synthesized, commercial one. The peptide yield was more than 4 mg/L culture, indicating this ubiquitin fusion technique is an attractive method for production of aggregation-prone peptides such as Abeta42.