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141.
Katrin?PlaumannEmail author Matthias?Weing Christian?Winkler Michael?Müller Enrico?Rukzio 《Personal and Ubiquitous Computing》2018,22(4):633-646
Pointing gestures are our natural way of referencing distant objects and thus widely used in HCI for controlling devices. Due to current pointing models’ inherent inaccuracies, most of the systems using pointing gestures so far rely on visual feedback showing users where they point at. However, in many environments, e.g., smart homes, it is rarely possible to display cursors since most devices do not contain a display. Therefore, we raise the question of how to facilitate accurate pointing-based interaction in a cursorless context. In this paper we present two user studies showing that previous cursorless techniques are rather inaccurate as they lack important considerations about users’ characteristics that would help in minimizing inaccuracy. We show that pointing accuracy could be significantly improved by acknowledging users’ handedness and ocular dominance. In a first user study (n=?33), we reveal the large effect of ocular dominance and handedness on human pointing behavior. Current ray-casting techniques neglect both ocular dominance and handedness as effects onto pointing behavior, precluding them from accurate cursorless selection. With a second user study (n=?25), we show that accounting for ocular dominance and handedness yields to significantly more accurate selections compared to two previously published ray-casting techniques. This speaks for the importance of considering users’ characteristics further to develop better selection techniques to foster more robust accurate selections. 相似文献
142.
Advanced SERS Sensor Based on Capillarity‐Assisted Preconcentration through Gold Nanoparticle‐Decorated Porous Nanorods 下载免费PDF全文
Longjian Xue Wei Xie Leonie Driessen Katrin F. Domke Yong Wang Sebastian Schlücker Stanislav N. Gorb Martin Steinhart 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(22)
A preconcentrating surface‐enhanced Raman scattering (SERS) sensor for the analysis of liquid‐soaked tissue, tiny liquid droplets and thin liquid films without the necessity to collect the analyte is reported. The SERS sensor is based on a block‐copolymer membrane containing a spongy‐continuous pore system. The sensor's upper side is an array of porous nanorods having tips functionalized with Au nanoparticles. Capillarity in combination with directional evaporation drives the analyte solution in contact with the flat yet nanoporous underside of the SERS sensor through the continuous nanopore system toward the nanorod tips where non‐volatile components of the analyte solution precipitate at the Au nanoparticles. The nanorod architecture increases the sensor surface in the detection volume and facilitates analyte preconcentration driven by directional solvent evaporation. The model analyte 5,5′‐dithiobis(2‐nitrobenzoic acid) can be detected in a 1 × 10?3m solution ≈300 ms after the sensor is brought into contact with the solution. Moreover, a sensitivity of 0.1 ppm for the detection of the dissolved model analyte is achieved. 相似文献
143.
Schulz Katrin Smets Sonja Velázquez-Quesada Fernando R. Xie Kaibo 《Journal of Logic, Language and Information》2022,31(2):235-260
Journal of Logic, Language and Information - The paper focuses on a recent challenge brought forward against the interventionist approach to the meaning of counterfactual conditionals. According to... 相似文献
144.
Definition of the problem
The term Advance Care Planning describes a concept of comprehensive planning for future health care situations that, amongst others, aims at supporting people to set up advance statements defining goals and desired directions of patient care, using qualified, prospective counseling offers. Another aim is to promote the dissemination and implementation of this concept with the help of structural, mostly regional measures.Arguments
This article discusses Advance Care Planning in psychiatry. It visualizes different forms of psychiatric advance statements and reports legal regulations from the US, Great Britain and Germany. Furthermore, this article provides an overview of international studies on the implementation of Advance Care Planning in psychiatry. These studies impressively illustrate the need of qualified counseling- and supportive offers, as without such offers, advance statements are hardly implemented and noticed in practice.Conclusion
Against this background, the authors recommend the experimental implementation of (regional) Advance Care Planning programs as pilot projects, aiming at ameliorating quality and acceptance of advance statements in psychiatry. These projects should be scientifically accompanied, evaluated and where necessary adjusted.145.
Muhammad Maqbool Qaisar Nawaz Muhammad Atiq Ur Rehman Mark Cresswell Phil Jackson Katrin Hurle Rainer Detsch Wolfgang H. Goldmann Asma Tufail Shah Aldo R. Boccaccini 《International journal of molecular sciences》2021,22(8)
In this study, as a measure to enhance the antimicrobial activity of biomaterials, the selenium ions have been substituted into hydroxyapatite (HA) at different concentration levels. To balance the potential cytotoxic effects of selenite ions (SeO32−) in HA, strontium (Sr2+) was co-substituted at the same concentration. Selenium and strontium-substituted hydroxyapatites (Se-Sr-HA) at equal molar ratios of x Se/(Se + P) and x Sr/(Sr + Ca) at (x = 0, 0.01, 0.03, 0.05, 0.1, and 0.2) were synthesized via the wet precipitation route and sintered at 900 °C. The effect of the two-ion concentration on morphology, surface charge, composition, antibacterial ability, and cell viability were studied. X-ray diffraction verified the phase purity and confirmed the substitution of selenium and strontium ions. Acellular in vitro bioactivity tests revealed that Se-Sr-HA was highly bioactive compared to pure HA. Se-Sr-HA samples showed excellent antibacterial activity against both Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus carnosus) bacterial strains. In vitro cell–material interaction, using human osteosarcoma cells MG-63 studied by WST-8 assay, showed that Se-HA has a cytotoxic effect; however, the co-substitution of strontium in Se-HA offsets the negative impact of selenium and enhanced the biological properties of HA. Hence, the prepared samples are a suitable choice for antibacterial coatings and bone filler applications. 相似文献
146.
The phase separation and morphology in poly(urethane urea)s were investigated as soft segment length and chain extender structure were varied. Increases in soft segment length led to increased phase separation that resulted in greater mobility of the soft segment. This was shown by lower soft segment glass transition temperatures in differential scanning calorimetry (DSC) as well as a shift of Emax″ and tan δmax to lower temperatures. Also the structure of the chain extender affected the degree of phase separation and mixing of the soft and the hard blocks in an interphase. Atomic force microscopy (AFM) was used to visualize the structure of the phase‐separated domains. The hard domains were in the form of spheres 5–10 nm, or long needles 5 nm thick and 50–300 nm long. As the soft segment length increased, there were more pure soft segment phase areas between the hard domains. At high hard segment content, a larger scale structure was found, consisting of both hard and soft segments.
147.
Dalia Angeles-Wedler Katrin Mackenzie Frank-Dieter Kopinke 《Applied catalysis. B, Environmental》2009,90(3-4):613-617
Pd-based catalysts have become important in environmental catalysis for their ability to hydrodechlorinate a wide range of chlorinated organic contaminants in water under ambient conditions. The success of their application in the remediation practice, e.g. for groundwater treatment, is often hindered by the sensitivity of Pd to poisoning by sulphur compounds. In this study, the stability and sulphide-induced deactivation behaviour of a highly active Pd/Al2O3 catalyst was investigated. The specific activity of Pd for the hydrodechlorination of chlorobenzene corresponds to rate coefficients up to kPd = 350 L g−1 min−1. The totally deactivated catalyst, resultant of sulphide poisoning, was regenerated with potassium permanganate. The pH value, as a key parameter which may influence the degree of deactivation as well as the efficiency of catalyst regeneration, was evaluated. Results show that in clean water the Pd/Al2O3 catalyst showed no inherent deactivation regardless of the ageing time and the pH value of the catalyst suspension. The degree of catalyst poisoning effected by 1.8–5.4 μM sulphide, corresponding to molar ratios of S:Pdsurface = 1.5–8.5, was observed to be higher under neutral and alkaline than under acidic conditions. The exposure of the catalyst to higher sulphide concentration of 14.2 μM resulted in complete catalyst deactivation regardless of the pH conditions. However, the efficacy of permanganate as oxidative regenerant for the fouled catalyst showed strong pH-dependence. A regeneration time of 10–30 min at low pH was sufficient to recover completely the high catalytic activity of Pd/Al2O3 for the hydrodechlorination reaction. 相似文献
148.
A biosensor for detecting the aromatic substance 4-nitrophenol based on Agrocybe aegerita peroxygenase (AaP) immobilized with chitosan-stabilized gold nanoparticles is presented here. This biosensor measures the enzymatic product of 4-nitrophenol peroxygenation, 4-nitrocatechol, which is electrochemically detected in the presence of hydrogen peroxide. Cyclic voltammetry and amperometry were used to characterize the proposed biosensor. The linear range of the AaP biosensor for the detection of 4-nitrophenol was between 10 and 30 μM with a detection limit of 0.2 μM (based on the S/N = 3). The catalytic property of AaP to oxidize 4-nitrophenol was compared with two other heme proteins, a camphor-hydroxylating cytochrome P450 monooxygenase (P450cam, CYP101) and horseradish peroxidase (HRP). The results revealed that only AaP is capable of catalyzing the hydroxylation of 4-nitrophenol into 4-nitrocatechol. Consequently, AaP could be a particularly potent biocatalyst that may fill the gap between cytochrome P450s and common heme peroxidases. 相似文献
149.
In this work, the potential of silicate nanotubes of the naturally occurring mineral halloysite as filler for polyamide 6 (PA 6) nanocomposites is evaluated. Several PA 6/halloysite composites with 0 wt% to 30 wt% filler loading using two different grades of PA 6 were prepared. In order to elucidate the influence of molecular weight on the properties of the nanocomposites, mechanical resp. rheological experiments (i) below the glass transition temperature Tg of PA 6, (ii) between Tg and the melting temperature Tm of PA 6 and (iii) above Tm were performed. Our investigations reveal that the addition of halloysite nanotubes favours the formation of the γ-modification for the low molar mass PA 6. Furthermore, the storage modulus, the tensile modulus and the yield stress of the composites increase with concentration of halloysite, an effect which is strongly pronounced at very low filler fractions for the low molar mass PA 6 composites. The increase of the storage modulus which was measured in dynamic-mechanical experiments is mostly dominant in the temperature interval from 55 °C to 100 °C, i.e. above the glass transition temperature of PA 6. Rheological investigations showed that the shear viscosity is only moderately increased by the addition of a low fraction of halloysite to PA 6, and nanocomposites with 30 wt% halloysite can be still processed. In summary, halloysite nanotubes are promising and inexpensive candidates for increasing the stiffness of PA 6 while maintaining very good flow properties. 相似文献
150.
Alexander Seifert Sandra Vomund Katrin Grohmann Sebastian Kriening Vlada B. Urlacher Priv.‐Doz. Dr. Sabine Laschat Prof. Dr. Jürgen Pleiss Prof. Dr. 《Chembiochem : a European journal of chemical biology》2009,10(5):853-861
Monooxygenase mutants : A minimal and highly enriched CYP102A1 mutant library was constructed by combining five hydrophobic amino acids in two positions. The library was screened with four different terpene substrates. Eleven variants demonstrated either a strong shift or improved regio‐ or stereoselectivity during oxidation of at least one substrate as compared to CYP102A1 wild type.