SUMMARY
Audit guidance requires auditors to assess management's competence with respect to internal controls over financial reporting (ICFR) based on the recommendations of COSO's integrated ...framework. The omission bias theory suggests that after internal control failures, auditors may assess managers' competence in a manner inconsistent with these requirements. Results from four experiments using 313 experienced audit and accounting professionals support this concern and a means of mitigating it. I find that auditors view the manager to be most competent when prior to the failure in the key control the manager did nothing to prevent the failure versus reinforced the key control. I do not find this effect when auditors had shared their concerns about the key control with the manager prior to the control's failure. My results also show that auditors incorporate their competence judgments about management into evaluations of the ICFR, as required by the audit guidance.
Electrochemotherapy of colorectal liver metastases has been proven to be feasible, safe and effective in a phase I/II study. In that study, a specific group of patients underwent two-stage operation, ...and the detailed histopathological evaluation of the resected tumors is presented here. Regressive changes in electrochemotherapy-treated liver metastases were evaluated after the second operation (in 8-10 weeks) in 7 patients and 13 metastases when the treated metastases were resected. Macroscopic and microscopic changes were analyzed. Electrochemotherapy induced coagulation necrosis in the treated area encompassing both tumor and a narrow band of normal tissue. The area became necrotic, encapsulated in a fibrous envelope while preserving the functionality of most of the vessels larger than 5 mm in diameter and a large proportion of biliary structures, but the smaller blood vessels displayed various levels of damage. At the time of observation, 8-10 weeks after electrochemotherapy, regenerative changes were already seen in the peripheral parts of the treated area. This study demonstrates regressive changes in the whole electrochemotherapy-treated area of the liver. Further evidence of disruption of vessels less than 5 mm in diameter and preservation of the larger vessels by electrochemotherapy is provided. These findings are important because electrochemotherapy has been indicated for the therapy of metastases near major blood vessels in the liver to provide a safe approach with good antitumor efficacy.
We propose to use artificial neural networks to process the experimental data and to predict the performance of the aerosol CVD synthesis of single-walled carbon nanotubes based on Boudouard ...reaction. We employ five key input parameters of the growth (pressures of CO, CO2 and ferrocene as well as the residence time and the growth temperature) to control the performance of produced nanotube films (yield, mean and standard deviation of the diameter distribution, and defectiveness). The prediction errors were found to be comparable with the corresponding experimental errors. We believe the proposed approach is of great interest for the synthesis of nanocarbons with tailored characteristics.
A schematic representation of the hierarchical architecture of the experimental setup and artificial neural network connection for controlled and predictive SWCNT synthesis. Display omitted
We report the results of four experiments investigating the relationship between (1) the quality of an audit, (2) jurors' assessments of the standard of prudent care (SOC) against which audit quality ...is compared, and (3) jurors' negligence verdicts. Experiment 1 operationalizes audit quality by varying the sample size used in audit testing, and provides evidence that jurors anchor their assessment of SOC on audit quality, producing a "competitive mediation" in which audit quality reduces the potential for a negligence verdict directly, but increases that potential indirectly by increasing SOC. Experiment 2 generalizes this finding to a setting that operationalizes audit quality by varying the size of adjustment the auditor required. Experiments 3 and 4 extend these results to a setting in which SOC is elicited after jurors make negligence verdicts. Overall, these experiments provide insight into the role of SOC in constraining and justifying negligence verdicts.
We propose a novel approach to enhance optoelectronic performance of single-walled carbon nanotubes (SWCNTs) for transparent conducting film applications. The method provides fine and reversible ...tuning of optoelectrical properties of SWCNT films over a wide range of parameters. Using imidazolium-based ionic liquid with a wide electrochemical window (BMIM-PF6), we achieved the film sheet resistance as low as 53 Ω/sq at the 90% transmittance, thereby shifting the SWCNT Fermi level up to 1.4 eV. We believe the results to promote collateral research of adjustable tuning of the electronic structure of carbon nanomaterials as promising components for future electronics, electrochromic devices, and ionotronics.
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A machine learning technique, namely, support vector regression, is implemented to enhance single-walled carbon nanotube (SWCNT) thin-film performance for transparent and conducting applications. We ...collected a comprehensive data set describing the influence of synthesis parameters (temperature and CO2 concentration) on the equivalent sheet resistance (at 90% transmittance in the visible light range) for SWCNT films obtained by a semi-industrial aerosol (floating-catalyst) CVD with CO as a carbon source and ferrocene as a catalyst precursor. The predictive model trained on the data set shows principal applicability of the method for refining synthesis conditions toward the advanced optoelectronic performance of multiparameter processes such as nanotube growth. Further doping of the improved carbon nanotube films with HAuCl4 results in the equivalent sheet resistance of 39 Ω/□one of the lowest values achieved so far for SWCNT films.
We investigate a complex relationship between structural parameters of single-walled carbon nanotubes (namely, mean length, diameter, and defectiveness) and optoelectrical properties (equivalent ...sheet resistance) of thin films composed of the nanotubes. We obtained a systematic dataset describing the influence of CO2 concentration and growth temperature. On the basis of the experimental results, we prove the high Raman peak ratio (IG/ID), length, and diameter of the nanotubes to decrease the equivalent sheet resistance of the nanotube-based film. The approach employed highlights the change in the nanotube growth mechanism at the temperature coinciding with the phase transition between α-Fe and γ-Fe catalyst phases. We believe this work to be of high interest for researchers working not only in the field of transparent and conductive films based on nanocarbons, but also for those who reveals the fundamentals of the nanotube growth mechanism.
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We assess bithiophene (C
H
S
) as a novel sulfur-based promotor for the growth of single-walled carbon nanotubes (SWCNTs) in the aerosol (floating catalyst) CVD method. Technologically suitable ...equilibrium vapor pressure and an excess of hydrocarbon residuals formed under its decomposition make bithiophene an attractive promoter for the production of carbon nanotubes in general and specifically for ferrocene-based SWCNT growth. Indeed, we detect a moderate enhancement in the carbon nanotube yield and a decrease in the equivalent sheet resistance of the films at a low bithiophene content, indicating the improvement of the product properties. Moreover, the relatively high concentrations and low temperature stability of bithiophene result in non-catalytical decomposition, leading to the formation of pyrolytic carbon deposits; the deposits appear as few-layer graphene structures. Thus, bithiophene pyrolysis opens a route for the cheap production of hierarchical composite thin films comprising carbon nanotubes and few-layer graphene, which might be of practical use for hierarchical adsorbents, protective membranes, or electrocatalysis.
This work contributes to the understanding of single-walled carbon nanotube synthesis by an aerosol CVD method using ethylene and toluene as a hybrid carbon source. We evaluated an extensive set of ...synthesis conditions revealing the role of ferrocene, toluene, and ethylene. We found the fundamental role of ethylene promoting nanotube nucleation and catalyst activation degree at all the concentrations studied, and enhancing nanotube growth at low ethylene content. We observed the interplay effect of toluene and ethylene concentrations on the nanotube growth rate, accompanied by the detrimental effect of toluene on catalyst activation degree. Nevertheless, toluene apparently promotes nanotube crystallinity, increasing the film conductivity while used as an individual carbon source. Adjusting the ethylene and toluene concentrations, we produced carbon nanotube-based transparent and conductive films with an equivalent sheet resistance (at 90% transmittance at 550 nm wavelength) value of 57 Ω/□ at the synthesis yield of 0.24 cm2 L−1, which is at least two times higher than the results reported earlier.
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•Ethylene boosts SWCNT nucleation and enhances catalyst activation degree.•Ethylene promotes growth rate but deactivates catalyst at high concentrations.•Toluene improves nanotube crystanillity and deteriorates catalyst activation degree.•Toluene and ethylene together yield in better performance unlike separate supply.•High-yield production of high-performance transparent conductive films demonstrated.
The generative potential of kerogenous shale sequences in the Caucasus Maykopian series, the southern part of European Russia, is evaluated. The Khadum and Batalpashin sediments in the Eastern and ...Central Fore-Caucasus include three types of kerogen: I, II and III. The Khadum sediments are dominated by a more "noble" type II kerogen, mixed humic-sapropelic organic matter (OM). The Maykopian series may be attributed to the category of "rich" and "very rich" ("outstanding") oil source rocks. The maturity extent of the subject sediments within the region varies between the grades of protokatagenesis (maximum pyrolysis temperature (T.sub.max) = 390 degreesC) and MC.sub.4 (T.sub.max = 471 degreesC). Based on the pyrolytic studies, the Khadum and Batalpashin sediments are distinct from other pelitic rocks in rather high generative potential values. The average value of the total generative potential (S.sub.1 + S.sub.2) in the studied samples from the Khadum and Batalpashin Formations is 4.83 mg HC/g rock. The quantitative estimate of the hydrocarbon generative potential of the Khadum and Batalpashin sediments in this region was conducted for the first time. The total initial generative hydrocarbon potential of the sediments is 133.4 BT, being 92.7 BT for the Khadum Formation, and 40.7 BT for the Batalpashin Formation. Keywords: organic carbon, katagenesis, generation potential, source rock, Khadum Formation, Batalpashin Formation, shale strata.
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