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TXRF is a microanalytical method for trace elemental determination. Common sample preparation comprises drying a sample volume in the microliter range on a hydrophobized reflector. However, such specimens often dry as "coffee-ring"-like deposits. It is reported in the literature that coffee-ring specimens are correlated with poor accuracy. Nonetheless, models suggest that coffee-ring specimens provide the least errors from primary absorption. With picoliter derived specimens, the position dependent analyte signal response can be investigated. Here we study the elemental sensitivities obtained from ring-like deposits prepared by pL-printing with respect to their radius and position relative to the detector field of view (FOV). To understand the influence of a ring-like deposit on the TXRF signal we (a) determined the detector FOV and (b) modelled the declining response with increasing offset and finally (c) designed a multiple ring specimen for experimental validation. The detector FOV was determined from 128 individual micro specimens (Co, Cu, Ga, and Ni) with defined offsets using an in-house-build pL-printer. The 2d Gaussian intensity profile of the FOV exhibits a mean of 26.7 cps−1 ng−1 (Co Kα), offset from the reflector centre by +0.62 mm (x-axis) and +0.28 mm (y-axis). The σ of the intensity profile is located at 2.4 mm (x-axis) and 2.2 mm (y-axis). At a distance of 9.47 mm (x) and 8.71 mm (y) (4σ) from the centre the counts are down to 10%. The local relative sensitivity (e.g., Co Kαoffset normalized to Ga Kαoffset) (RS) corresponded well to the mean RS of all positions (e.g., Co Kαmean normalized to Ga Kαmean). The position-dependent errors in signal intensities were evaluated experimentally with concentric ring structures (Co, Cu, Ga, and Mn) with up to 6 mm distance from the centre. The bias originating from a total spatial separation of the IS and the analyte and location of the IS in the centre and analyte on circles of different radii was determined. A negative bias of 33% was observed for the 2 mm radius circle, 80% for the 4 mm radius and 99% for the 6 mm radius circle. The observation for the two inner circles matches the determined FOV profile. [ABSTRACT FROM AUTHOR]

This paper compares four journal ranking metrics, namely the Australian Business Deans Council (ABDC) journal quality list, Cabells' Classification Index, Journal Impact Factor, and CiteScore, commonly used by the business school community. Using multiple statistical analyses, such as distribution box plots, correlation analysis and mean-comparison t-tests, of a sample of 138 ABDC journals in the field of accounting and finance, our results show that there is a significant correlation between Cabell Classification Index, the Journal Impact Factor or CiteScore and the benchmark ranking, the ABDC rating. We find fewer differences between the ABDC benchmark journal ranking and the Cabells' Classification Index when the cutoff is 31% versus 50%. The Journal Impact Factor and CiteScore, however, are more similar to the benchmark ranking. Given the inconsistency in journal ranking metrics, business schools and departments are recommended not to rely on a single ranking measure for assessing faculty publication quality. [ABSTRACT FROM AUTHOR]

Silicon is a promising material for tissue engineering since it allows to produce micropatterned scaffolding structures resembling biological tissues. Using specific fabrication methods, it is possible to build aligned 3D network-like structures. In the present study, we exploited vertically-aligned silicon micropillar arrays as culture systems for human iPSC-derived cortical progenitors. In particular, our aim was to mimic the radially-oriented cortical radial glia fibres that during embryonic development play key roles in controlling the expansion, radial migration and differentiation of cortical progenitors, which are, in turn, pivotal to the establishment of the correct multilayered cerebral cortex structure. Here we show that silicon vertical micropillar arrays efficiently promote expansion and stemness preservation of human cortical progenitors when compared to standard monolayer growth conditions. Furthermore, the vertically-oriented micropillars allow the radial migration distinctive of cortical progenitors in vivo. These results indicate that vertical silicon micropillar arrays can offer an optimal system for human cortical progenitors’ growth and migration. Furthermore, similar structures present an attractive platform for cortical tissue engineering. [ABSTRACT FROM AUTHOR]

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There is a strong correlation between undergraduate courses in accounting fraud and graduates' abilities to detect fraud and to appropriately respond to internal control material weaknesses in work environments. However, many scholars have indicated a failure in academic education because external auditors usually detect only about 5% of fraud cases. The authors of this study review and analyze certain "weaknesses" in academic educators, academic institutions, literature, internal control topics, and contents/relevance. The latter includes: topics related to internal control, educational topics about fraud and forensic accounting, weak content related to ethics education, current ethics education that instill core ethical values, ethics integration among academic institutions, relative decline in the quality of accounting education, differences between academic and professional education, frustration with information technology, lack of topics related to data analytics, and the weakness in teaching forensic accounting. [ABSTRACT FROM AUTHOR]

The question of how to teach internal control and anti-fraud topics effectively has caused much debate in the academic profession during the last twenty years. Following the fraud scandals, critics turned their attention toward universities to know whether accounting programs do prepare students to recognize frauds in their future works. Some views in the literature confirm the strength of accounting education. Some scholars have lamented the failure of academic educations in preparing accounting students to detect and respond to fraud appropriately. This study covers the various perceptions about forensic accounting education, ethics education, internal control education, and fraud education Then the study covers various perspectives of Employers' perspectives regarding fraud education, students' perspectives regarding fraud education, educators' perspectives regarding fraud education, educators' perspectives regarding fraud education, and accountants' perspectives regarding fraud education. Finally the authors draw a conclusion of their study. [ABSTRACT FROM AUTHOR]

This research tests whether Holderness Jr., D. K., Myers, N., Summers, S. L., & Wood, D. A. [(2014). Accounting education research: Ranking institutions and individual scholars. Issues in Accounting Education, 29 (1), 87-115] accounting-education rankings are sensitive to a change in the set of journals used. It provides updated rankings for accounting-education authors from Australia, Canada, New Zealand, the Republic of Ireland, the United Kingdom, and the United States using a sample that included the publications in 13 accountingeducation journals. Our analysis indicated that Holderness et al.'s rankings of authors and departments were significantly different from our rankings. This research provides rankings of the top 50 authors and departments for three periods: from 2010 to 2015, from 2004 to 2015, and from 1992 to 2015. We provide data indicating the distribution of authors for these periods to assist authors not listed in the most prolific lists in determining their relative ranking. Finally, we provide data on the distribution of journal choices for accounting-education publications for the authors from each country. [ABSTRACT FROM AUTHOR]

AISI 1045 steel has been widely used as the substrate for thin film deposition. In some cases, an ultra-smooth surface of AISI 1045 steel is needed and is even indispensible for the satisfactory deposition of thin film. In this paper, chemical mechanical polishing technique was employed to prepare the ultra-smooth surface of AISI 1045 steel. The effects of pH and HO on the polishing performance of AISI 1045 steel were investigated. It is revealed that, with the increase of pH, the material removal rate (MRR) and the static etching rate (SER) of AISI 1045 steel gradually decrease due to the formation of passive iron oxides on the top surface, and thus the surface quality gradually improves. At pH 4.00, with the addition of HO, the SER of AISI 1045 steel is further suppressed; while the MRR of AISI 1045 steel first dramatically increases due to the formation of porous iron oxides with relatively low mechanical strength on the surface when the HO concentration increases from 0 to 0.01 wt%, and then decreases since the porous iron oxides gradually grow compact when the HO concentration further increases. The increase of the compactness of the iron oxides might be attributed to the crystallization of γ-FeOOH into α-FeOOH and even into α-FeO and the resulting polymerization of the amorphous iron oxides. [ABSTRACT FROM AUTHOR]

Total Reflection X-ray Fluorescence (TXRF) analysis is a well-established analytical method in the semiconductor industry for the analysis of silicon wafer surfaces. To improve the detection limits of TXRF (given in at cm−2) for wafer surface analysis vapor phase decomposition-droplet collection (VPD-DC) is used to collect the impurities of the total surface in one droplet. This leads to higher sample masses to be analyzed than in straight TXRF. In TXRF, absorption effects concerning the excitation and the detected radiation are usually disregarded. This is justified because mostly small sample amounts (pg to ng range) are used and the thin film approximation is valid. For higher total amounts of sample deviations from the linear relation between the fluorescence intensity and sample amount have been observed (saturation effect). These lead to difficulties in quantification with external standard, which is the calibration method used in TXRF wafer surface analysis. The content of the presented work is an investigation of the absorption phenomenon and hence the fluorescence intensity to improve the quantification of TXRF using VPD-DC. Samples with different total amounts of nickel were prepared and the emitted fluorescence intensities were measured at two different excitation energies to estimate the upper limit of sample mass where the relation between the fluorescence intensity and sample amount diverges from linearity depending on the excitation energy. The measurement results were compared to calculations performed with a self-developed simulation model. It could be verified that if the excitation energy is closer to the absorption edge of the excited element (which means better excitation) the saturation effect appears at a lower sample mass. [ABSTRACT FROM AUTHOR]

Total reflection X-ray fluorescence analysis (TXRF) offers a nondestructive qualitative and quantitative analysis of trace elements. Due to its outstanding properties TXRF is widely used in the semiconductor industry for the analysis of silicon wafer surfaces and in the chemical analysis of liquid samples. Two problems occur in quantification: the large statistical uncertainty in wafer surface analysis and the validity of using an internal standard in chemical analysis. In general TXRF is known to allow for linear calibration. For small sample amounts (low nanogram (ng) region) the thin film approximation is valid neglecting absorption effects of the exciting and the detected radiation. For higher total amounts of samples deviations from the linear relation between fluorescence intensity and sample amount can be observed. This could be caused by the sample itself because inhomogeneities and different sample shapes can lead to differences of the emitted fluorescence intensities and high statistical errors. The aim of the study was to investigate the elemental distribution inside a sample. Single and multi-element samples were investigated with Synchrotron-radiation-induced micro X-ray Fluorescence Analysis (SR-μ-XRF) and with an optical microscope. It could be proven that the microscope images are all based on the investigated elements. This allows the determination of the sample shape and potential inhomogeneities using only light microscope images. For the multi-element samples, it was furthermore shown that the elemental distribution inside the samples is homogeneous. This justifies internal standard quantification. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Filling microstructures in the air with liquid or removing trapped gases from a surface in a liquid are required in processes such as cleaning, bonding, and painting. However, it is difficult to deform the gas–liquid interface to fill a small hole with liquid when surface tension has closed one end. Therefore, it is necessary to have an efficient method of removing gas from closed-end holes in liquids. Here, we demonstrate the gas-removing method using acoustic waves from small holes. We observed gas column oscillation by changing the hole size, wettability, and liquid surface tension to clarify the mechanism. First, we found that combining two different frequencies enabled complete gas removal in water within 2 s. From high-speed observation, about half of the removal was dominated by droplet or film formation caused by oscillating the gas column. The other half was dominated by approaching and coalescing the divided gas column. We conclude that the natural frequency of both the air column and the bubbles inside the tube are important. [ABSTRACT FROM AUTHOR]

We present an overview of the investigations on the transport of near-resonant light in laser-cooled atomic vapors, a field that emerged during the past decade. We first discuss time-resolved measurements yielding some informations on the nature of this transport, which is quasi-diffusive for low temperatures and limited optical thicknesses. We then focus on the coherence of the transport, which is probed using the coherent backscattering interference. We identify and analyze in detail several mechanisms limiting the coherence length in such media. [ABSTRACT FROM AUTHOR]