Thiol-Rich fp-6 Controls the Tautomer Equilibrium of Oxidized Dopa in Interfacial Mussel Foot Proteins.

3,4-Dihydroxyphenylalanine (Dopa) is a versatile molecule that enables marine mussels to achieve successful underwater adhesion. However, due to its complicated redox chemistry and vulnerability to oxidation, controlling surface adhesion and cohesion has been a challenging issue to overcome. Foot protein type 6 (fp-6), a thiol-rich interfacial mussel adhesive protein, has been reported as a proteinaceous antioxidant for mussels that helps Dopa maintain surface adhesion ability. In this study, we focused on the role of fp-6 in oxidized Dopa. The effect on the tautomer equilibrium of oxidized Dopa was investigated using recombinant fp-6 (rfp-6) and Dopa-incorporated foot protein type 3 fast variant (drfp-3F), which were produced in bacterial cells. The redox chemistry of Dopa in drfp-3F and the role of rfp-6 were observed using a UV-vis spectrophotometer and a surface forces apparatus (SFA). We discovered that rfp-6 shifts the tautomer equilibrium to ΔDopa as a preferred tautomer for oxidized Dopa in drfp-3F and makes drfp-3F better on underwater surface adhesion.

Enhanced production of Dopa-incorporated mussel adhesive protein using engineered translational machineries.

Mussel adhesive proteins (MAPs) have great potential as bioglues, particularly in wet conditions. Although in vivo residue-specific incorporation of 3,4-dihydroxyphenylalanine (Dopa) in tyrosine-auxotrophic Escherichia coli cells allows for production of Dopa-incorporated bioengineered MAPs (dMAPs), the low production yield hinders the practical application of dMAPs. This low production yield of dMAPs is due to low translational activity of a noncanonical amino acid, Dopa, in E. coli cells. Herein, to enhance the production yield of dMAPs, we investigated the coexpression of Dopa-recognizing tyrosyl-tRNA synthetases (TyrRSs). To use the Dopa-specific Methanococcus jannaschii TyrRS (MjTyrRS-Dopa), we altered the anticodon of tyrosyl-tRNA amber suppressor into AUA (MjtRNATyrAUA ) to recognize a tyrosine codon (AUA). Co-overexpression of MjTyrRS-Dopa and MjtRNATyrAUA increased the production yield of Dopa-incorporated MAP foot protein type 3 (dfp-3) by 57%. Similarly, overexpression of E. coli TyrRS (EcTyrRS) led to a 72% higher production yield of dfp-3. Even with coexpression of Dopa-recognizing TyrRSs, dfp-3 has a high Dopa incorporation yield (over 90%) compared to ones prepared without TyrRS coexpression.

Effects of Si/SiO2 interface stress on the performance of ultra-thin-body field effect transistors: a first-principles study.

First-principles density functional theory (DFT) based device simulations are performed for Si ultra-thin-body (UTB) field effect transistors with the explicit SiO2 atoms in the gate dielectric. In order to evaluate the Si/SiO2 interface stress effects on the UTB device performance, the interface stress tensor is extracted from the Si/SiO2 atomic structure by DFT calculations. The influence of the interface stress on the transport properties is examined through full quantum mechanical non-equilibrium Green's function calculations. Based on the analysis of the band structure and transfer characteristics, we demonstrate that the interface stress can characterize the overall effects of the SiO2 gate dielectric on the device performance in the nanoscale regime.

Nonorthogonal [Formula: see text] tight-binding parameterization of single-layer phosphorene under biaxial strain and application to FETs.

This paper presents a new set of [Formula: see text] tight-binding (TB) parameters for single-layer phosphorene within the Naval Research Laboratory (NRL) scheme. For this, we develop the numerical algorithm to find the NRL TB parameters fitted to ab initio results. It is shown that the proposed NRL TB parameters successfully reproduce the band structure of a single-layer phosphorene, and even under biaxial or uniaxial strain, they appropriately describe the effects, such as modification of anisotropic effective masses and band gap. Via the top-of-the-barrier model, we also investigate the performance of single-layer phosphorene FETs under biaxial strain with the NRL TB Hamiltonian and find that the results are well in accordance with those of previous studies.

The Augmented Cognitive Mediation Model: Examining Antecedents of Factual and Structural Breast Cancer Knowledge Among Singaporean Women.

As knowledge acquisition is an important component of health communication research, this study examines factors associated with Singaporean women's breast cancer knowledge using an augmented cognitive mediation model. We conducted a nationally representative study that surveyed 802 women between the ages of 30 and 70 using random-digit dialing. The results supported the augmented cognitive mediation model, which proposes the inclusion of risk perception as a motivator of health information seeking and structural knowledge as an additional knowledge dimension. There was adequate support for the hypothesized paths in the model. Risk perception was positively associated with attention to newspaper, television, Internet, and interpersonal communication. Attention to the three media channels was associated with interpersonal communication, but only newspaper and television attention were associated with elaboration. Interpersonal communication was positively associated with structural knowledge, whereas elaboration was associated with both factual and structural knowledge. Differential indirect effects between media attention and knowledge dimensions via interpersonal communication and elaboration were found. Theoretical and practical implications are discussed.

Effect of silicide/silicon hetero-junction structure on thermal conductivity and Seebeck coefficient.

We fabricated a thermoelectric device with a silicide/silicon laminated hetero-structure by using RF sputtering and rapid thermal annealing. The device was observed to have Ohmic characteristics by I-V measurement. The temperature differences and Seebeck coefficients of the proposed silicide/silicon laminated and bulk structure were measured. The laminated thermoelectric device shows suppression of heat flow from the hot to cold side. This is supported by the theory that the atomic mass difference between silicide and silicon creates a scattering center for phonons. The major impact of our work is that phonon transmission is suppressed at the interface between silicide and silicon without degrading electrical conductivity. The estimated thermal conductivity of the 3-layer laminated device is 126.2 +/- 3.7 W/m. K. Thus, by using the 3-layer laminated structure, thermal conductivity is reduced by around 16% compared to bulk silicon. However, the Seebeck coefficient of the thermoelectric device is degraded compared to that of bulk silicon. It is understood that electrical conductivity is improved by using silicide as a scattering center.

Adaptive variable sampling model for performance analysis in high cache-performance computing environments.

High-performance computing provides computing power for a variety of scientific disciplines, supporting advancements by offering insights beyond metacognition. Maximizing computing performance without wasting resources is a major research issue. Predicting the performance of a computer's next state is effective for scheduling. However, hardware performance monitors representing the computer's state require high expert knowledge, and there is no standardized model. In this paper, we propose an adaptive variable sampling model for performance analysis in high-performance computing environments. Our method automatically classifies the optimal variables from numerous variables related to performance prediction and predicts performance using the sampled variables. The optimal variables for performance analysis do not require expert knowledge during the sampling process. We conducted experiments in various architectures and applications to validate this method. This model performed at least 24.25% and up to 58.75% faster without any loss in accuracy.

Complex disaster response framework to reduce urban disaster vulnerability.

Cities are vulnerable to a range of disasters that can occur simultaneously due to their complexity. Therefore, an effective disaster response plan is needed to reduce the disaster vulnerability of cities. In particular, evacuation route management is important for reducing the losses from a disaster. Efficient disaster response can be realized by searching for suitable evacuation routes and effective road network management. In this paper, we propose a disaster response framework based on a multilayered road network structure and evacuation routes based on our road network. The suggested road structure consists of three layers for the effective management of the network. An A* algorithm-based search for multiple evacuation routes under different conditions in response to an individual disaster on the configured road map provides a safe route for evacuees. As a result, the damage caused by disasters in urban areas can be ameliorated.

Stenotrophomonas daejeonensis sp. nov., isolated from sewage.

A Gram-stain-negative, motile, aerobic bacterial strain, designated MJ03(T), was isolated from sewage and was characterized taxonomically by using a polyphasic approach. Comparative 16S rRNA gene sequence analysis showed that strain MJ03(T) belongs to the family Xanthomonadaceae, class Gammaproteobacteria, and was related most closely to Stenotrophomonas acidaminiphila AMX 19(T) (97.9  % sequence similarity), Stenotrophomonas humi R-32729(T) (97.1  %), Stenotrophomonas nitritireducens L2(T) (96.9  %), Stenotrophomonas maltophila ATCC 13637(T) (96.8  %) and Stenotrophomonas terrae R-32768(T) (96.7  %). The G+C content of the genomic DNA of strain MJ03(T) was 64.7 mol%. The detection of a quinone system with ubiquinone Q-8 as the predominant component and a fatty acid profile with iso-C15:0, iso-C11:0, iso-C14:0, iso-C17:1ω9c, iso-C11:0 3-OH and iso-C13:0 3-OH as major components supported the affiliation of strain MJ03(T) to the genus Stenotrophomonas. However, levels of DNA-DNA relatedness between strain MJ03(T) and the type strains of five closely related species of the genus Stenotrophomonas ranged from 11 to 34  %, showing clearly that the isolate represents a novel genospecies. Strain MJ03(T) could be differentiated clearly from its phylogenetic neighbours on the basis of several phenotypic, genotypic and chemotaxonomic features. Therefore, strain MJ03(T) is considered to represent a novel species of the genus Stenotrophomonas, for which the name Stenotrophomonas daejeonensis sp. nov. is proposed. The type strain is MJ03(T) (=KCTC 22451(T) =JCM 16244(T)).

Quantum mechanical simulation of hole transport in p-type Si Schottky barrier MOSFETs.

A full quantum-mechanical simulation of p-type nanowire Schottky barrier metal oxide silicon field effect transistors (SB-MOSFETs) is performed by solving the three-dimensional Schrödinger and Poisson's equations self-consistently. The non-equilibrium Green's function (NEGF) approach is adopted to treat hole transport, especially quantum tunneling through SB. In this work, p-type nanowire SB-MOSFETs are simulated based on the 3-band k.p method, using the k.p parameters that were tuned by benchmarking against the tight-binding method with sp3s* orbitals. The device shows a strong dependence on the transport direction, due to the orientation-sensitive tunneling effective mass and the confinement energy. With regard to the subthreshold slope, the [110] and [111] oriented devices with long channel show better performance, but they are more vulnerable to the short channel effects than the [100] oriented device. The threshold voltage also shows a greater variation in the [110] and [111] oriented devices with the decrease of the channel length.

Hole-effective masses in the transport calculation of Si nanowire pMOSFETs.

The full-quantum, self-consistent simulation of p-type silicon nanowire field effect transistors based on the k * p method is performed and their device characteristics are examined in the light of the hole-effective masses. An attempt is made in this study to assess the role of the hole-effective masses by devising simple, single-band parabolic effective mass (PEM) Hamiltonians and comparing the transport characteristics with the ones from the k * p method. It is found that the PEM Hamiltonian with isotropic effective masses fails to correctly produce both the scaling behavior of the subthreshold currents and the behavior of the on-currents with respect to the silicon orientation. A modified PEM model with light-hole effective mass in the transport direction and quantization effective mass in the perpendicular direction greatly improve the subthreshold behavior for all the silicon orientations, which shows that the top-most light-hole subband dominantly determines the subthreshold behavior. The modified PEM model however overestimates the on-currents, indicating the limitation of the model.

Critical switching current density of magnetic tunnel junction with shape perpendicular magnetic anisotropy through the combination of spin-transfer and spin-orbit torques.

Recently, magnetic tunnel junctions (MTJs) with shape perpendicular magnetic anisotropy (S-PMA) have been studied extensively because they ensure high thermal stability at junctions smaller than 20 nm. Furthermore, spin-transfer torque (STT) and spin-orbit torque (SOT) hybrid switching, which guarantees fast magnetization switching and deterministic switching, has recently been achieved in experiments. In this study, the critical switching current density of the MTJ with S-PMA through the interplay of STT and SOT was investigated using theoretical and numerical methods. As the current density inducing SOT ([Formula: see text]) increases, the critical switching current density inducing STT ([Formula: see text]) decreases. Furthermore, for a given [Formula: see text], [Formula: see text] increases with increasing thickness, whereas [Formula: see text] decreases as the diameter increases. Moreover, [Formula: see text] in the plane of thickness and spin-orbit field-like torque ([Formula: see text]) was investigated for a fixed [Formula: see text] and diameter. Although [Formula: see text] decreases with increasing [Formula: see text], [Formula: see text] slowly increases with increasing thickness and increasing [Formula: see text]. The power consumption was investigated as a function of thickness and diameter at the critical switching current density. Experimental confirmation of these results using existing experimental techniques is anticipated.

Enhancement of perceived body ownership in virtual reality-based teleoperation may backfire in the execution of high-risk tasks.

Guided by previous research on the role of embodiment in virtual environments, this study aimed to investigate the potential effects of using human-like (compared to robotic) virtual hands on work performances in the context of virtual reality (VR)-based teleoperation of high-risk machinery. A 2 × 2 mixed factorial design experiment (N = 74), with the virtual hand representation as a within-subjects factor (robotic vs. human-like virtual hands) and the risk of danger as a between-subjects factor (low vs. high), was conducted to examine the effects of virtual hand representations (i.e., human-likeness) on perceived body ownership (i.e., embodiment), risk perception, intention to work using the teleoperator, and work performance (i.e., the number of successful task completions). In addition, the moderating effects of the risk of danger on the relationship between perceived body ownership and risk perception were explored. Results showed that the enhancement of perceived body ownership in VR-based teleoperation, induced by the use of human-like hands, increased the risk perception and degraded workers' task performances in the execution of high-risk tasks. Further implications of the findings were discussed.

Oriented in situ immobilization of a functional tyrosinase on microcrystalline cellulose effectively incorporates DOPA residues in bioengineered mussel adhesive protein.

BACKGROUND: Catechol-containing polymers such as mussel adhesive proteins (MAPs) are attractive as biocompatible adhesive biomaterials, and the catecholic amino acid 3,4-dihydroxyphenyl-L-alanine (DOPA) is considered a key molecule in underwater mussel adhesion. Tyrosinases can specifically convert tyrosine to DOPA without any cofactors. However, their catalytic properties still need to be adjusted to minimize unwanted DOPA oxidation via their diphenolase activity and catechol instability at neutral and basic pH values in the reaction products. METHODS AND RESULTS: In this work, we constructed a novel functional tyrosinase, mTyr-CNK_CBM, by fusion of mTyr-CNK with a cellulose-binding motif (CBM) for oriented in situ immobilization on microcrystalline cellulose via the C-terminal CBM without any additional purification steps. mTyr-CNK_CBM showed optimal catalytic activity at pH 4.5-6.5 and room temperature and had a high monophenolase/diphenolase activity ratio (Vmax mono/Vmax di = 2.08 at pH 6 and 25°C). mTyr-CNK_CBM exhibited 2.17-fold higher (as a unimmobilized free enzyme) and similarly high (upon immobilization) in vitro DOPA modification of a bioengineered MAP compared to a commercially available mushroom tyrosinase. Moreover, the immobilized mTyr-CNK_CBM showed long-term storability and improved reusability. CONCLUSIONS: These results clearly demonstrate a strong potential for practical use of immobilized mTyr-CNK_CBM as a monophenol monooxygenase in preparing biocompatible DOPA-tethered biomaterials and other catechol-containing polymers.

Aqueous humor and plasma levels of vascular endothelial growth factor and interleukin-8 in patients with central serous chorioretinopathy.

PURPOSE: The purpose of this study was to determine aqueous vascular endothelial growth factor (VEGF) and interleukin-8 (IL-8) levels in patients with central serous chori-oretinopathy (CSC) before a single intravitreal bevacizumab injection. METHODS: Twelve eyes with symptomatic CSC were included. Samples from patients with cataracts served as controls. The levels of VEGF and IL-8 concentrations were measured in aqueous humor and plasma by multiplex bead assays. RESULTS: All patients with CSC showed an improvement in visual acuity and resolved neurosensory detachment after intravitreal bevacizumab injection. The aqueous humor levels of VEGF and IL-8 were not significantly increased in patients with CSC compared with the healthy control group (18.2 ± 24.8 vs. 35.3 ± 28.5 pg/mL, P > 0.05; 2.3 ± 0.4 vs. 2.8 ± 0.3 pg/mL, P > 0.05, respectively). The plasma levels of VEGF and IL-8 in patients with CSC were not different from those in the healthy control group. CONCLUSION: Vascular endothelial growth factor and IL-8 were not increased in the aqueous humor and plasma of patients with CSC. The effect of intravitreal bevacizumab injection as a treatment for CSC must be fully understood, and the true effect of anti-VEGF treatment in patients with CSC remains to be elucidated.

Pegylated-interferon-associated retinopathy in chronic hepatitis patients.

PURPOSE: To investigate the clinical features of pegylated-interferon (PEG-IFN)-associated retinopathy in chronic hepatitis patients. METHODS: We examined a consecutive case series of 46 patients who were treated with PEG-IFN for chronic hepatitis C or B between October 2007 and September 2008. All patients underwent regular ophthalmologic examinations every 3 weeks during the 6 months after treatment. RESULTS: Ten of the 46 patients (21.73%) developed retinal abnormalities. PEG-IFN-associated retinopathy occurred a mean of 7.25 +/- 10.28 weeks after treatment and manifested itself as cotton wool spots and retinal hemorrhages. All patients, except for 1 with a retinal vein occlusion, recovered without cessation of treatment. CONCLUSIONS: PEG-IFN-associated retinopathy in chronic hepatitis patients was reversible, and patients recovered without visual complications; however, 1 patient did present with an irreversible visual impairment. This type of retinopathy is usually asymptomatic, and clinicians should closely observe patients for 3 months after treatment.

Maximization of acoustic energy difference between two spaces.

There has recently been an increasing interest in the generation of a sound field that is audible in one spatial region and inaudible in an adjacent region. The method proposed here ensures the control of the amplitude and phase of multiple acoustic sources in order to maximize the acoustic energy difference between two adjacent regions while also ensuring that evenly distributed source strengths are used. The performance of the method proposed is evaluated by computer simulations and experiments with real loudspeaker arrays in the shape of a circle and a sphere. The proposed method gives an improvement in the efficiency of radiation into the space in which the sound should be audible, while maintaining the acoustic pressure difference between two acoustic spaces. This is shown to give an improvement of performance compared to the contrast control method previously proposed.

The position of lysine controls the catechol-mediated surface adhesion and cohesion in underwater mussel adhesion.

Intensive studies have found that 3,4-dihydroxyphenylalanine (Dopa) is one of the key molecules for underwater mussel adhesion. Although basic mechanisms of mussel adhesion have been elucidated, little is known about how mussels control the balance between surface adhesion and cohesion, which is critical for successful adhesion without peeling and/or tearing. In this work, we focused on lysine (Lys) molecules which are frequently flanked to Dopa residues in interfacial adhesive proteins, specifically their synergy and anti-synergy on surface adhesion and cohesion. Three model peptides were designed to characterize flanking Lys effects. Through nano-mechanistic analyses, we found that flanking Lys enhanced surface adhesion but disrupted Fe3+-mediated cohesion. Through nuclear magnetic resonance analyses and density functional theory calculations, we corroborated the synergetic effect on surface adhesion and anti-synergetic effect on cohesion. We also confirmed the consistency of flanking Lys effects in the actual protein system. Thus, we, for the first time, discovered that each Dopa molecule in interfacial adhesive proteins is participated in surface adhesion and cohesion differently through controlling the existence of flanking Lys. Our discovery enlightens how nature designs adhesive proteins through according roles of Dopa.

Harnessing the bioresponsive adhesion of immuno-bioglue for enhanced local immune checkpoint blockade therapy.

Despite the great promise of immune checkpoint blockade (ICB) therapy for cancer treatment, the currently available options for ICB treatment pose major clinical challenges, including the risk of severe systemic autoimmune responses. Here, we developed a novel localized delivery platform, immuno-bioglue (imuGlue), which is inspired by the intrinsic underwater adhesion properties of marine mussels and can allow the optimal retention of anti-PD-L1 drugs at tumor sites and the on-demand release of drugs in response to the tumor microenvironment. Using a triple-negative breast cancer and melanoma models, we found that imuGlue could significantly enhance anti-tumor efficacy by eliciting a robust T cell-mediated immune response while reducing systemic toxicity by preventing the rapid diffusion of anti-PD-L1 drugs into the systemic circulation and other tissues. It was also demonstrated that imuGlue could be successfully utilized for combination therapy with other immunomodulatory drugs to enhance the anti-tumor efficacy of ICB-based immunotherapy, demonstrating its versatility as a new treatment option for cancer immunotherapy.

Uncanny Valley Effects on Friendship Decisions in Virtual Social Networking Service.

Drawing on the uncanny valley effects (UVE) hypothesis and related works on avatar-based interactions, this study investigates the role of UVE (i.e., a feeling of eeriness), induced by avatar realism and animacy, on the perceived trustworthiness (PT) of an avatar user, and subsequent decisions to befriend that avatar user in a virtual social networking service (SNS). Specifically, the current study examines whether (1) the realism (hyperrealistic vs. cartoonish) and animacy (animate vs. still) of avatars, rendered through a 3D scanning technology, will induce a feeling of eeriness as a result of UVE; (2) the degree to which perceivers experience a feeling of eeriness will negatively bias the PT of an avatar user; and (3) PT, determined by UVE, will serve a role as a gating mechanism for the decision whether to befriend the unknown avatar user in a virtual SNS. Results from a two (realism: cartoonish vs. hyperrealistic) × two (animacy: still vs. animate) between-subjects online experiment (N = 134) indicated that a feeling of eeriness, induced by the realism and animacy of avatars, negatively biased the PT of the avatar user, and this, in turn, led avatar perceivers to reject a friend request sent from the unknown avatar user. These results call into the question the effectiveness of rendering avatar realism in social virtual environments. Overall, the findings of our research provide theoretical as well as practical implications for the design of avatars in virtual SNSs.