Evaluating and improving modeled turbulent heat fluxes across the North American Great Lakes

Turbulent fluxes of latent and sensible heat are important physical processes that influence the energy and water budgets of the North American Great Lakes. These fluxes can be measured in situ using eddy covariance techniques and are regularly included as a component of lake–atmosphere models. To help ensure accurate projections of lake temperature, circulation, and regional meteorology, we validated the output of five algorithms used in three popular models to calculate surface heat fluxes: the Finite Volume Community Ocean Model (FVCOM, with three different options for heat flux algorithm), the Weather Research and Forecasting (WRF) model, and the Large Lake Thermodynamic Model. These models are used in research and operational environments and concentrate on different aspects of the Great Lakes' physical system. We isolated only the code for the heat flux algorithms from each model and drove them using meteorological data from four over-lake stations within the Great Lakes Evaporation Network (GLEN), where eddy covariance measurements were also made, enabling co-located comparison. All algorithms reasonably reproduced the seasonal cycle of the turbulent heat fluxes, but all of the algorithms except for the Coupled Ocean–Atmosphere Response Experiment (COARE) algorithm showed notable overestimation of the fluxes in fall and winter. Overall, COARE had the best agreement with eddy covariance measurements. The four algorithms other than COARE were altered by updating the parameterization of roughness length scales for air temperature and humidity to match those used in COARE, yielding improved agreement between modeled and observed sensible and latent heat fluxes.</p

A Minimal Threshold of c-di-GMP Is Essential for Fruiting Body Formation and Sporulation in Myxococcus xanthus

Generally, the second messenger bis-(3’-5’)-cyclic dimeric GMP (c-di-GMP) regulates the switch between motile and sessile lifestyles in bacteria. Here, we show that c-di-GMP is an essential regulator of multicellular development in the social bacterium Myxococcus xanthus. In response to starvation, M. xanthus initiates a developmental program that culminates in formation of spore-filled fruiting bodies. We show that c-di-GMP accumulates at elevated levels during development and that this increase is essential for completion of development whereas excess c-di-GMP does not interfere with development. MXAN3735 (renamed DmxB) is identified as a diguanylate cyclase that only functions during development and is responsible for this increased c-di-GMP accumulation. DmxB synthesis is induced in response to starvation, thereby restricting DmxB activity to development. DmxB is essential for development and functions downstream of the Dif chemosensory system to stimulate exopolysaccharide accumulation by inducing transcription of a subset of the genes encoding proteins involved in exopolysaccharide synthesis. The developmental defects in the dmxB mutant are non-cell autonomous and rescued by co-development with a strain proficient in exopolysaccharide synthesis, suggesting reduced exopolysaccharide accumulation as the causative defect in this mutant. The NtrC-like transcriptional regulator EpsI/Nla24, which is required for exopolysaccharide accumulation, is identified as a c-diGMP receptor, and thus a putative target for DmxB generated c-di-GMP. Because DmxB can be—at least partially—functionally replaced by a heterologous diguanylate cyclase, these results altogether suggest a model in which a minimum threshold level of c-di-GMP is essential for the successful completion of multicellular development in M. xanthus

The Impact of Error-Management Climate, Error Type and Error Originator on Auditors’ Reporting Errors Discovered on Audit Work Papers

We examine factors affecting the auditor’s willingness to report their own or their peers’ self-discovered errors in working papers subsequent to detailed working paper review. Prior research has shown that errors in working papers are detected in the review process; however, such detection rates only rarely exceed 50% of the seeded errors. Hence, measures that encourage auditors to be alert to their own (or their peers’) potential errors any time they revisit the audit working papers may be valuable in detecting such residual errors and potentially correcting them before damage occurs to the audit firm or its client. We hypothesize that three factors affect the auditor’s willingness to report post detailed review discovered errors: the local office error-management climate (open versus blame), the type of error (mechanical versus conceptual) and who committed the error (the individual who committed the error (self) or a peer). Local office error-management climate is said to be open and supportive where errors and mistakes are accepted as part of everyday life as long as they are learned from and not repeated. In alternative, a blame error-management climate focuses on a “get it right the first time” culture where mistakes are not tolerated and blame gets attached to those admitting to or found committing such errors. We find that error-management climate has a significant overall effect on auditor willingness to report errors, as does who committed the error originally. We find both predicted and unpredicted significant interactions among the three factors that qualify these observed significant main effects. We discuss implications for audit practice and further research

Error management in audit firms: Error climate, type, and originator

This paper examines how the treatment of audit staff who discover errors in audit files by superiors affects their willingness to report these errors. The way staff are treated by superiors is labelled as the audit office error management climate. In a "blame-oriented" climate errors are not tolerated and those committing errors are punished. In contrast, an "open" climate characterizes error commitment as a normal, albeit unfortunate aspect of organizational life that offers opportunities for learning without sanctions on the originator. We examine error management climate in the context of audit-specific factors that might affect the decision to report errors: audit error type (conceptual or mechanical) and who committed the error (the individual who discovered it or a peer). An open climate results in an increase in the reporting of mechanical (but not conceptual) errors and all peer errors versus a blame climate. Post hoc findings suggest that one obstacle to reporting conceptual errors stems from an auditor's own impression management concerns. We discuss how auditing standards and regulatory inspections may impact audit firm error management climates

Reporting Self-Made Errors: The Impact of Organizational Error-Management Climate and Error Type

We study how an organization's error-management climate affects organizational members' beliefs about other members' willingness to report errors that they discover when chance of error detection by superiors and others is extremely low. An error-management climate, as a component of the organizational climate, is said to be "high" when errors are accepted as part of everyday life as long as they are learned from and not repeated. Alternatively, the error-management climate is said to be an "error averse" climate when discovery of errors invokes the laying of blame on those admitting to or found committing errors. We examine the effects of this error-management climate in a professional services environment where uncorrected errors may have severe consequences and discovery of work errors is crucial for organizational success. We find that error-management climate affects organizational members' beliefs about what other members will report about discovered self-made errors, with a high error-management (versus error averse) climate leading to greater reporting willingness. We also find a significant interaction with a key contextual variable, error type (conceptual or calculation), that suggests the effect is more significant for conceptual errors than calculation errors. Our findings suggest that an organization's error-management climate is an important factor in promoting ethical behavior of employees, especially junior employees, carrying out routine tasks whose failure to report errors discovered incidental to those tasks may have severe implications for their organizations. © 2012 Springer Science+Business Media Dordrecht

Financial Statement Users¿ Perceptions of the IAASB¿s ISA 700 Unqualified Auditor¿s Report in Germany and the Netherlands

We report on the results of an experiment, in which experienced auditors and users (financial analysts as sophisticated users and students as unsophisticated users) read a brief company description, a summary of the firm¿s financial statements, and an audit report, the latter of which we manipulated as being either the complete auditor¿s report according to the revised ISA 700 or a short-form audit opinion-only version. Participants then responded to questions related to the perceived responsibility of the auditor versus management for producing the financial statements, detecting and preventing fraud, the soundness of the firm¿s internal control structure, etc.; and to the reliability of the financial statements with respect to misstatements, fraud, errors, etc. We find strong evidence for a persisting audit expectation gap between auditors and financial statement users under the revised ISA 700 auditor¿s report. Also, results are robust in indicating that the detailed explanations of the ISA 700 auditor¿s report of auditor versus management responsibilities and the task and scope of the audit are not effective in reducing this expectation gap, and partially even have a detrimental effect

The Impact of Error-Management Climate, Error Type and Error Originator on Auditors’ Reporting Errors Discovered on Audit Work Papers

We examine factors affecting the auditor’s willingness to report their own or their peers’ self-discovered errors in working papers subsequent to detailed working paper review. Prior research has shown that errors in working papers are detected in the review process; however, such detection rates only rarely exceed 50% of the seeded errors. Hence, measures that encourage auditors to be alert to their own (or their peers’) potential errors any time they revisit the audit working papers may be valuable in detecting such residual errors and potentially correcting them before damage occurs to the audit firm or its client. We hypothesize that three factors affect the auditor’s willingness to report post detailed review discovered errors: the local office error-management climate (open versus blame), the type of error (mechanical versus conceptual) and who committed the error (the individual who committed the error (self) or a peer). Local office error-management climate is said to be open and supportive where errors and mistakes are accepted as part of everyday life as long as they are learned from and not repeated. In alternative, a blame error-management climate focuses on a “get it right the first time†culture where mistakes are not tolerated and blame gets attached to those admitting to or found committing such errors. We find that error-management climate has a significant overall effect on auditor willingness to report errors, as does who committed the error originally. We find both predicted and unpredicted significant interactions among the three factors that qualify these observed significant main effects. We discuss implications for audit practice and further research.review;adjustments;audit quality;materiality

Global Transcriptional Response of Bacillus subtilis to Heat Shock

In response to heat stress, Bacillus subtilis activates the transcription of well over 100 different genes. Many of these genes are members of a general stress response regulon controlled by the secondary sigma factor, ς(B), while others are under control of the HrcA or CtsR heat shock regulators. We have used DNA microarrays to monitor the global transcriptional response to heat shock. We find strong induction of known ς(B)-dependent genes with a characteristic rapid induction followed by a return to near prestimulus levels. The HrcA and CtsR regulons are also induced, but with somewhat slower kinetics. Analysis of DNA sequences proximal to newly identified heat-induced genes leads us to propose ∼70 additional members of the ς(B) regulon. We have also identified numerous heat-induced genes that are not members of known heat shock regulons. Notably, we observe very strong induction of arginine biosynthesis and transport operons. Induction of several genes was confirmed by quantitative reverse transcriptase PCR. In addition, the transcriptional responses measured by microarray hybridization compare favorably with the numerous previous studies of heat shock in this organism. Since many different conditions elicit both specific and general stress responses, knowledge of the heat-induced general stress response reported here will be helpful for interpreting future microarray studies of other stress responses