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Co3O4 nanocubes are evaluated concerning their intrinsic electrocatalytic activity towards the oxygen evolution reaction (OER) by means of single-entity electrochemistry. Scanning electrochemical cell microscopy (SECCM) provides data on the electrocatalytic OER activity from several individual measurement areas covering one Co3O4 nanocube of a comparatively high number of individual particles with sufficient statistical reproducibility. Single-particle-on-nano-electrode measurements of Co3O4 nanocubes provide an accelerated stress test at highly alkaline conditions with current densities of up to 5.5 Acm-2, and allows to derive TOF values of up to 2.8 X104 s-1 at 1.92 V vs. RHE for surface Co atoms of a single cubic nanoparticle. Obtaining such high current densities combined with identical-location transmission electron microscopy allows monitoring the formation of an oxy(hydroxide) surface layer during electrocatalysis. Combining two independent single-entity electrochemistry techniques provides the basis for elucidating structure–activity relations of single electrocatalyst nanoparticles with well-defined surface structure. ; This research obtained funding from the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) within the collaborative research centre/transregio 247 "Heterogeneous Oxidation Catalysis in the Liquid Phase" TRR 247 [388390466] (projects A2 and C3) as well as under Germany's Excellence Strategy-EXC 2033-390677874-RESOLV. This project has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant agreement CasCat [833408]). The mechanical workshop team at the faculty of chemistry and biochemistry, Ruhr University Bochum, is acknowledged for the contribution in designing and building the nanoelectrode TEM holder. We acknowledge Prof. Patrick Unwin from the University of Warwick for providing the initial control software (WEC-SPM) for our SECCM experiments. Open Access funding enabled and organized by ...

A representative sample of the US adult pop was interviewed during the week following the assassination of President J. F. Kennedy. 66.6% said they were aware of the event half an hour after it happened, almost all within 2 hours. Most activity halted as people turned to radio or TV for further reports. First reactions, even of Kennedy's pol'al opponents, were of personal grief & loss rather than pol'al concern. Various physical & emotional symptoms were reported, but by time of interview these had largely subsided. There was little ideological fervor evident, even when it became known that the alleged assassin held leftist views; little anger was directed toward him, & there was a general desire that L. H. Oswald's own slayer receive a fair trial. Finally, the survey found no change in certain basic beliefs & values of the US public, as compared with pre-assassination measurements. (See SA 0827-B3417 & 0828-B3438). AA.

A single quadrupole combined with enhanced in-source fragmentation/annotation (EISA) was used to perform multiple reaction monitoring (Q-MRM) for quantitative mass spectrometry analysis. EISA amplifies fragmentation of traditional soft electrospray ionization to produce fragment ions that have been found to be identical to those generated in tandem mass spectrometry. We have combined EISA fragmentation data with criteria established by the European Union Commission Directive 2002/657/EC for electron ionization single quadrupole quantitative analysis to perform quantitative Q-MRM experiments. These experiments were performed on multiple types of complex samples that included a mixture of 50 standards, as well as cell and plasma extracts. The dynamic range for Q-MRM quantitative analysis was comparable to triple quadrupole multiple reaction monitoring (QqQ-MRM) analyses at up to 5 orders of magnitude with the cell and plasma extracts showing similar matrix effects across both platforms. Amino acid and fatty acid measurements performed from certified NIST 1950 plasma with isotopically labelled standards demonstrated Q-MRM accuracy in the range of 91-110% for the amino acids, 76-129% for the fatty acids, and good precision (coefficient of variation < 10%). In order to enhance specificity, a newly developed Correlated Ion Monitoring (CIM) algorithm was designed to facilitate these analyses. CIM autonomously processes, aligns, filters, and compiles multiple ions within one chromatogram enabling both precursor and in-source fragment ions to be correlated within a single chromatogram, also enabling the detection of co-eluting species based on precursor and fragment ion ratios. Q-MRM and CIM with single quadrupole instrumentation has been designed as an alternative to QqQ-MRM technology by correlating precursor and fragment ions to facilitate high sensitivity Q-MRM quantitative analysis on existing instrumentation that are generally inexpensive, easy to operate, and technically less complex. @font-face {font-family:"Cambria Math"; panose-1:2 4 5 3 5 4 6 3 2 4; mso-font-charset:0; mso-generic-font-family:roman; mso-font-pitch:variable; mso-font-signature:3 0 0 0 1 0;}p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-unhide:no; mso-style-qformat:yes; mso-style-parent:""; margin:0in; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman",serif; mso-fareast-font-family:"Times New Roman";}.MsoChpDefault {mso-style-type:export-only; mso-default-props:yes; font-size:11.0pt; mso-ansi-font-size:11.0pt; mso-bidi-font-size:11.0pt; font-family:"Calibri",sans-serif; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:DengXian; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi; mso-fareast-language:ZH-CN;}.MsoPapDefault {mso-style-type:export-only; margin-bottom:8.0pt; line-height:107%;}div.WordSection1 {page:WordSection1;}

In this paper, investigations were carried out on the effects of simultaneous partial substitution of Tl at the Hg site on the physical properties of an Hg1-xTlxBa2Ca2Cu3O8+δ cuprate superconductor with x= 0, 0.1, 0.2, 0.3 and 0.4. Two steps of the solid state reaction method were used to prepare samples in capsule. The results showed that the optimum sintering temperature was equal to 850 ᵒC and the sintering time was equal to 20 h for the prepared samples.
The best conditions for constitution and stabilization of the high Tc phase-1223 were obtained by investigating the effects of Tl substitution on Hg site and oxygen content (δ) on the superconducting properties.
Structural investigation revealed that all the samples have a tetragonal structure with two phases, namely an Hg-1223 high Tc phase as a main phase and an Hg-1212 low Tc phase. Besides, some impurity phases like CuO and CaHgO2 were found. The increase of Tl content in Hg1-xTlxBa2Ca2Cu3O8+δ compound from 0 to 0.4 caused a change in the lattice parameter, density of the unit cell (ρm), and c/a values.
HgBa2Ca2Cu3O8+δ compound exhibited a critical transition temperature that is equal to 115 K. On the other side, the results showed that the highest Tc was 119 K for Hg0.8Tl0.2 Ba2Ca2Cu3O8+δ. The oxygen content (δ= 0.46) was expected to be the optimum hole doping for Hg0.8Tl0.2 Ba2Ca2Cu3O8+δ compound, which means in our opinion that δ plays a remarkable role in the assessment of Tc.

Objective: The study explores associations of visually induced motion sickness (VIMS) with emergency braking reaction times (RTs) in driving simulator studies. It examines the effects over the progression of multiple simulated drives. Background: Driving simulator usage has many advantages for RT studies; however, if it induces VIMS, the observed driving behavior might deviate from real-world driving, potentially masking or skewing results. Possible effects of VIMS on RT have long been entertained, but the progression of VIMS across simulated drives has so far not been sufficiently considered. Method: Twenty-eight adults completed six drives on 2 days in a fixed-base driving simulator. At five points during each drive, pedestrians entered the road, necessitating emergency braking maneuvers. VIMS severity was assessed every minute using the 20-point Fast Motion Sickness Scale. The progression of VIMS was considered in mixed model analyses. Results: RT predictions were improved by considering VIMS development over time. Here, the relationship of VIMS and RT differed across days and drives. Increases in VIMS symptom severity predicted more prolonged RT after repeated drives on a given day and earlier within each drive. Conclusion: The assessment of VIMS in RT studies can be beneficial. In this context, VIMS measurements in close temporal proximity to the behaviors under study are promising and offer insights into VIMS and its consequences, which are not readily obtainable through questionnaires. Application: Driving simulator–based RT studies should consider cumulative effects of VIMS on performance. Measurement and analysis strategies that consider the time-varying nature of VIMS are recommended.

This paper reports an economic, simple, and rapid FI-CL method for the determination of MCPA. This method requires simple instrumentation and it is fast enough to be used in routine analyses. A chemiluminescence signal is generated by reaction between photodegraded MCPA and ferricyanide solution in alkaline medium. All physical and chemical parameters in the flow injection chemiluminescence system were optimized in the experimental setting. To eliminate interference, a solid-phase extraction stage with SDB-1 cartridges and ethanol elution is applied. The signal-MCPA concentration relation is linear in concentration intervals between 0.0015 and 0.6 ¿g¿mL -1. The calibration lines are statistically similar in different working conditions: standards with ethanol without extraction and standards with ethanol and extraction, allowing standards to be excluded from the extraction step, which simplifies the process. The detection limit (DL) is 0.5 ng¿mL -1, which is the same order as the maximum limit established in legislation regarding pesticide limits in water destined for human consumption. A DL of 0.13 ng¿mL -1 can be reached if a sample of 100 mL is preconcentrated. The interday variance coefficient is 3% and the sample throughput is 90 h -1. The water analysis method is efficient with relative error percentages lower than 5% with respect to the added concentration. © 2011 Springer-Verlag. ; Authors acknowledge to the "Ministerio de Educacion y Ciencia" of Spain and FEDER funds for financial support (Project CTM2006-11991) ; Torres Cartas, S.; Gómez Benito, C.; Meseguer-Lloret, S. (2012). FI on-line chemiluminescence reaction for determination of MCPA in water samples. Analytical and Bioanalytical Chemistry. 402:1289-1296. https://doi.org/10.1007/s00216-011-5567-1 ; S ; 1289 ; 1296 ; 402 ; Navarro JS (2008) Utilización de plaguicidas en las asociaciones de tratamientos integrados en agricultura en la región de Murcia. Consejería de Sanidad Región de Murcia ; Barceló D, Hennion MC (1997) Trace determination of ...

The commonly used curing system for chloroprene rubber (CR) is a combination of two metal oxides, such as magnesium oxide (MgO) and zinc oxide (ZnO). Application of MgO and ZnO enables to obtain a good balance between processability of rubber compounds and mechanical properties of the vulcanizates. Despite high activity in crosslinking reactions, ZnO is classified as ecotoxic to aquatic organisms, thus environmental legislation requires its quantity in technology to be limited. In our studies more environmentally friendly curing systems were applied, which enabled eliminating ZnO from CR compounds. These curing systems consisted of manganese acetylacetonate (Mn(acac)) or nickel acetylacetonate (Ni(acac)) and triethanolamine (TEOA) used as a base necessary to perform Heck's reaction. Both metal acetylacetonates exhibited high activity in crosslinking reactions, which was confirmed by a great torque increment during rheometric measurements and high degree of elastomer crosslinking. The type of metal acetylacetonate and the amount of TEOA seemed to have less influence on the efficiency of the curing system than the filler used. Rubber compounds filled with carbon black (CB) were characterized by definitely shorter optimal vulcanization times and higher degree of crosslinking compared to CR composites filled with nanosized SiO(2). Moreover, application of the proposed curing systems allowed to obtain CR vulcanizates with mechanical properties comparable with the benchmarks cured with metal oxides.

Abstract Purpose: This article investigated the reaction of the Brazilian stock market to the Covid-19 pandemic and the characteristics that made some companies less vulnerable than others based on the measurement of abnormal returns using the event study methodology. Originality/value: The article contributes to informed decision-making, as the results expand the literature on the impacts of extreme events on the stock market of an emerging country, contributing to investors' risk and portfolio management strategies. Design/methodology/approach: March 11, 2020, was considered the reference date, the day of the pandemic announcement by the World Health Organization. The event window included five days before and after the reference date, which covers some of the milestones of the pandemic's beginning, such as the first internal transmission, the first death in Brazil, and the record of community transmission. The abnormal return was estimated using the market model, and the regression model was used to explain the accumulated abnormal return, analyzing the importance of the characteristics of the companies. Findings: The results showed that 98 companies presented negative and significant cumulative abnormal return (CAR), representing 71.53% of the total sample. Furthermore, the shares of the companies in the sample had an accumulated abnormal return of -26.85%, indicating the magnitude of the influence on companies' prices. In specific terms, it was found that publicly traded companies that are larger, less leveraged, with lower turnover, and that adhere to responsibility practices suffered less adverse impact at the beginning of the pandemic.

One of the leading indicators of how well an e-government system is being implemented is how much citizen acceptance of e-government has increased. Thus, this study looks at social and psychological traits and uncertainty avoidance as moderating factors to identify the factors influencing Indonesian citizens' adoption of e-government. SEM-PLS was utilized for data analysis. An online survey with measurement questions tailored to 520 respondents was used to gather data for the proposed model's quantitative validation. A purposive sampling approach based on self-selection was used in this study. The analysis findings show that citizens' intents as end users of e-government systems are significantly and positively impacted by the influence of compatibility (β = 0.265; p &amp;lt; 0.05), relative advantage (β = 0.482; p &amp;lt; 0.05), and trust in e-government websites (β = 0.243; p &amp;lt; 0.05). On the other hand, complexity (β= –0.293; p &amp;lt; 0.05) significantly and negatively affects their intention to use the system. Additionally, the connection between relative advantage (β = 0.213; p &amp;lt; 0.05), complexity (β = 0.294; p &amp;lt; 0.05), compatibility (β = 0.275; p &amp;lt; 0.05), and propensity to use e-government was found to be moderated by uncertainty avoidance. Encouraging citizens to use e-government will aid the Indonesian government by increasing individuals' experience with the system and potentially lowering their perception of its hazards.

PurposeAssessment gamification, which refers to the addition of game elements to existing assessments, is commonly implemented to improved applicant reactions to existing psychometric measures. This study aims to understand the effects of gamification on applicant reactions to and measurement quality of situational judgment tests.Design/methodology/approachIn a 2 × 4 between-subjects experiment, this study randomly assigned 315 people to experience different versions of a gamified situational judgment test, crossing immersive game elements (text, audio, still pictures, video) with control game elements (high and low), measuring applicant reactions and assessing differences in convergent validity between conditions.FindingsThe use of immersive game elements improved perceptions of organizational technological sophistication, but no other reactions outcomes (test attitudes, procedural justice, organizational attractiveness). Convergent validity with cognitive ability was not affected by gamification.Originality/valueThis is the first study to experimentally examine applicant reactions and measurement quality to SJTs based upon the implementation of specific game elements. It demonstrates that small-scale efforts to gamify assessments are likely to lead to only small-scale gains. However, it also demonstrates that such modifications can be done without harming the measurement qualities of the test, making gamification a potentially useful marketing tool for assessment specialists. Thus, this study concludes that utility should be considered carefully and explicitly for any attempt to gamify assessment.

The present paper attempts to expand the existing literature on Central Bank Independence (CBI) by proposing new measures for CBI. It designs two indices: one tackling the de jure CBI and the other assessing the de facto level of CBI. The two measures outweigh traditional measures in various aspects; first, the two indices are more comprehensive in terms of possible institutional arrangements. The de jure index incorporates several aspects related to CBI that were not previously grouped together in a unified index i.e. financial independence, limitations related to indirect credit to government, accountability and transparency. The de facto index comprises the main existing indicators for measuring actual CBI (i.e. turnover ratio, political vulnerability indicator and monetary policy reaction function) in addition to new variables, as the lender of last resort function, independence of central bank board, and financial independence that were not included in almost all previous studies. Second, the two indices allow a higher level of precision as they comprise aspects that can be objectively codified with a minimum level of subjectivity. Third, the two indices cover the same attributes of CBI to facilitate measuring the deviation between de jure and de facto level of independence for any central bank. The current paper provides a comprehensive definition and analysis of both indices to enable their replication in future studies.

AbstractIn this Application Note, a versatile and reliable measurement system for photoelectrochemical investigations is described which aims to assist scientists in obtaining reproducible photoelectrochemical data of high quality, including the solar‐to‐hydrogen (STH) efficiency. Specifically, it addresses the parameters irradiation quality, reaction temperature, and gas measurement. The setup is designed to exclude stray light and uses a solar‐grade mirror to reflect the light of a vertical solar simulator on the electrochemical cell. The light quality in the setup (»AAA«, IEC 60904‐9) is close to the classification of the solar simulator itself. The temperature in the electrochemical cell is controlled with an external Peltier element and can be kept constant in the range of 20–45°C. The influence of reaction temperature on the photocurrent of a WO3 photoanode is demonstrated. The gaseous reaction products are analyzed with a mobile gas chromatograph, using an automated measurement routine with discontinuous sampling from the electrochemical cell. The system is applied to determine the Faraday and STH efficiencies of a copper indium gallium selenide photocathode.

Neuromotor intervention approaches, based on central nervous system development among nonhandicapped infants and young children, are presently the most popular motor training approaches with cerebral palsied children. Empirical data in support of neuromotor or other approaches to motor training, however, are lacking. In response to the absence of a data base, the theoretical basis and effectiveness of a neuromotor intervention was investigated across seven cerebral palsied, severely handicapped children, ages 2 1/2 to 12 years. Results suggested a training effect in the data of three children. Theoretical relationships among abnormal tonic reflexes and normal motor patterns were not supported by the data. Because results were not consistent across all children, it was suggested that future research focus on subject characteristics that may relate to the effectiveness of intervention. Additionally, recommendations were made regarding measurement systems for evaluating change, and strategies for investigating multicomponent training procedures.

This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Running agility is required for many sports and other physical tasks that demand rapid changes in body direction. Quantifying agility skill remains a challenge because measuring rapid changes of direction and quantifying agility skill from those measurements are difficult to do in ways that replicate real task/game play situations. The objectives of this study were to define and to measure agility performance for a (five-cone) agility drill used within a military obstacle course using data harvested from two foot-mounted inertial measurement units (IMUs). Thirty-two recreational athletes ran an agility drill while wearing two IMUs secured to the tops of their athletic shoes. The recorded acceleration and angular rates yield estimates of the trajectories, velocities and accelerations of both feet as well as an estimate of the horizontal velocity of the body mass center. Four agility performance metrics were proposed and studied including: 1) agility drill time, 2) horizontal body speed, 3) foot trajectory turning radius, and 4) tangential body acceleration. Additionally, the average horizontal ground reaction during each footfall was estimated. We hypothesized that shorter agility drill performance time would be observed with small turning radii and large tangential acceleration ranges and body speeds. Kruskal-Wallis and mean rank post-hoc statistical analyses revealed that shorter agility drill performance times were observed with smaller turning radii and larger tangential acceleration ranges an d body speeds, as hypothesized. Moreover, measurements revealed the strategies that distinguish high versus low performers. Relative to low performers, high performers used sharper turns, larger changes in body speed (larger tangential acceleration ranges), and shorter duration footfalls that generated larger horizontal ground reactions during the turn phases. Overall, this study advances the use of foot-mounted IMUs to quantify agility performance in contextually-relevant settings (e.g., field of play, training facilities, obstacle courses, etc.).

While standard solar model (SSM) predictions depend on approximately 20 input parameters, SSM neutrino flux predictions are strongly correlated with a single model output parameter, the core temperature T-c. Consequently, one can extract physics from solar neutrino flux measurements while minimizing the consequences of SSM uncertainties, by studying flux ratios with appropriate power-law weightings tuned to cancel this T-c dependence. We reexamine an idea for constraining the primordial C + N content of the solar core from a ratio of CN-cycle O-15 to pp-chain B-8 neutrino fluxes, showing that non-nuclear SSM uncertainties in the ratio are small and effectively governed by a single parameter, the diffusion coefficient. We point out that measurements of both CN-I cycle neutrino branches-O-15 and N-13 beta-decay-could, in principle, lead to separate determinations of the core C and N abundances, due to out-of-equilibrium CN-cycle burning in the cooler outer layers of the solar core. Finally, we show that the strategy of constructing "minimum uncertainty" neutrino flux ratios can also test other properties of the SSM. In particular, we demonstrate that a weighted ratio of Be-7 and B-8 fluxes constrains a product of S-factors to the same precision currently possible with laboratory data. ; A. M. S. is partially supported by the European Union International Reintegration No. PIRG-GA-2009-247732, the MICINN Grant No. AYA2011-24704, by the ESF EUROCORES Program EuroGENESIS (MICINN Grant No. EUI2009-04170), by SGR Grants of the Generalitat de Catalunya and by the EU-FEDER funds. C. P.-G. is supported in part by the Spanish MICINN Grants No. FPA-2007-60323 and No. FPA2011-29678, the Generalitat Valenciana Grant No. PROMETEO/2009/116 and the ITN INVISIBLES (Marie Curie Actions, PITN-GA-2011-289442). This work was supported in part by the U.S. DOE under Grants No. DE-SC00046548 (Berkeley) and No. DE-AC02-98CH10886 (LBL). W. H. thanks the INT and GSI for their hospitality while part of this work was done, and the Alexander von Humboldt Foundation for its support. ; Peer reviewed