30 resultados para Forensic audit
em Digital Commons at Florida International University
Resumo:
The volatile chemicals which comprise the odor of the illicit drug cocaine have been analyzed by adsorption onto activated charcoal followed by solvent elution and GC/MS analysis. A series of field tests have been performed to determine the dominant odor compound to which dogs alert. All of our data to date indicate that the dominant odor is due to the presence of methyl benzoate which is associated with the cocaine, rather than the cocaine itself. When methyl benzoate and cocaine are spiked onto U.S. currency, the threshold level of methyl benzoate required for a canine to signal an alert is typically 1-10 $\mu$g. Humans have been shown to have a sensitivity similar to dogs for methyl benzoate but with poorer selectivity/reliability. The dominant decomposition pathway for cocaine has been evaluated at elevated temperatures (up to 280$\sp\circ$C). Benzoic acid, but no detectable methyl benzoate, is formed. Solvent extraction and SFE were used to study the recovery of cocaine from U.S. currency. The amount of cocaine which could be recovered was found to decrease with time. ^
Resumo:
Cardiac troponin I (cTnI) is one of the most useful serum marker test for the determination of myocardial infarction (MI). The first commercial assay of cTnI was released for medical use in the United States and Europe in 1995. It is useful in determining if the source of chest pains, whose etiology may be unknown, is cardiac related. Cardiac TnI is released into the bloodstream following myocardial necrosis (cardiac cell death) as a result of an infarct (heart attack). In this research project the utility of cardiac troponin I as a potential marker for the determination of time of death is investigated. The approach of this research is not to investigate cTnI degradation in serum/plasma, but to investigate the proteolytic breakdown of this protein in heart tissue postmortem. If our hypothesis is correct, cTnI might show a distinctive temporal degradation profile after death. This temporal profile may have potential as a time of death marker in forensic medicine. The field of time of death markers has lagged behind the great advances in technology since the late 1850's. Today medical examiners are using rudimentary time of death markers that offer limited reliability in the medico-legal arena. Cardiac TnI must be stabilized in order to avoid further degradation by proteases in the extraction process. Chemically derivatized magnetic microparticles were covalently linked to anti-cTnI monoclonal antibodies. A charge capture approach was also used to eliminate the antibody from the magnetic microparticles given the negative charge on the microparticles. The magnetic microparticles were used to extract cTnI from heart tissue homogenate for further bio-analysis. Cardiac TnI was eluted from the beads with a buffer and analyzed. This technique exploits banding pattern on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) followed by a western blot transfer to polyvinylidene fluoride (PVDF) paper for probing with anti-cTnI monoclonal antibodies. Bovine hearts were used as a model to establish the relationship of time of death and concentration/band-pattern given its homology to human cardiac TnI. The final concept feasibility was tested with human heart samples from cadavers with known time of death. ^
Resumo:
The investigations of human mitochondrial DNA (mtDNA) have considerably contributed to human evolution and migration. The Middle East is considered to be an essential geographic area for human migrations out of Africa since it is located at the crossroads of Africa, and the rest of the world. United Arab Emirates (UAE) population inhabits the eastern part of Arabian Peninsula and was investigated in this study. Published data of 18 populations were included in the statistical analysis. The diversity indices showed (1) high genetic distance among African populations and (2) high genetic distance between African populations and non-African populations. Asian populations clustered together in the NJ tree between the African and European populations. MtDNA haplotypes database of the UAE population was generated. By incorporating UAE mtDNA dataset into the existing worldwide mtDNA database, UAE Forensic Laboratories will be able to analyze future mtDNA evidence in a more significant and consistent manner. ^
Resumo:
This dissertation examined three issues associated with Section 404 of the Sarbanes-Oxley Act (SOX) that are of current interest to regulators and the accounting profession. For the first essay, I examined auditor changes from 2003 to 2005 for 2,454 non-financial firms that filed their initial SOX 404 opinions prior to July 1, 2005. My results showed that there is a significant association between the receipt of an adverse SOX 404 opinion and auditor resignations - both before and after the issuance of the SOX 404 opinion. The data related to auditor dismissals show that clients are not successful in opinion shopping, since clients dismissing the auditor before the SOX 404 report also are more likely to receive an adverse SOX 404 opinion than clients not changing auditors. My second essay examined the relation between audit committee characteristics and changes in material weaknesses in internal control over financial reporting under the new SOX regime. My results showed that improvements in internal control in the second year of SOX are associated with: (1) the number of audit committee members and (2) financial expertise of audit committee members. My third essay examined the relation between the appointment of the new executives and the subsequent receipt of initial section 404 of SOX opinions. My results showed that adverse SOX 404 reports will be more likely at firms that recently hired a new chief financial officer (CFO).
Resumo:
The Internet has become an integral part of our nation’s critical socio-economic infrastructure. With its heightened use and growing complexity however, organizations are at greater risk of cyber crimes. To aid in the investigation of crimes committed on or via the Internet, a network forensics analysis tool pulls together needed digital evidence. It provides a platform for performing deep network analysis by capturing, recording and analyzing network events to find out the source of a security attack or other information security incidents. Existing network forensics work has been mostly focused on the Internet and fixed networks. But the exponential growth and use of wireless technologies, coupled with their unprecedented characteristics, necessitates the development of new network forensic analysis tools. This dissertation fostered the emergence of a new research field in cellular and ad-hoc network forensics. It was one of the first works to identify this problem and offer fundamental techniques and tools that laid the groundwork for future research. In particular, it introduced novel methods to record network incidents and report logged incidents. For recording incidents, location is considered essential to documenting network incidents. However, in network topology spaces, location cannot be measured due to absence of a ‘distance metric’. Therefore, a novel solution was proposed to label locations of nodes within network topology spaces, and then to authenticate the identity of nodes in ad hoc environments. For reporting logged incidents, a novel technique based on Distributed Hash Tables (DHT) was adopted. Although the direct use of DHTs for reporting logged incidents would result in an uncontrollably recursive traffic, a new mechanism was introduced that overcome this recursive process. These logging and reporting techniques aided forensics over cellular and ad-hoc networks, which in turn increased their ability to track and trace attacks to their source. These techniques were a starting point for further research and development that would result in equipping future ad hoc networks with forensic components to complement existing security mechanisms.
Resumo:
Issues related to the composition of audit committees have attracted significant interest from legislators and regulators in recent years. In my dissertation, I examine one overlooked component of audit committee composition – namely, the presence of female directors on the audit committee. I empirically test to see if there are any differences in the functioning of audit committee when there is at least one female director on the audit committee. My dissertation examines three issues: audit committee diligence, audit pricing and earnings management. ^ The absence of females on corporate boards has become the focus of legislators in some countries. Prior research, in a variety of contexts, suggests that women are in general more conservative in their judgments and decisions. The first part of my dissertation empirically shows that the presence of at least one female director on the audit committee makes the audit committee have more meetings. The second essay empirically examines if there is a positive association between audit fees and the presence of female directors in the audit committee. I posit that having a female director on the audit committee will result in higher audit fees. I find no significant evidence to show that audit fees are higher when there is a female director on the audit committee. The third part of my dissertation empirically examines if there an association between the presence of a female director on the audit committee and earnings management. I find no significant evidence to show that the presence of female directors on the audit committee constrains earnings management. Overall, the results suggest that having a female on the audit committee changes the form – if not the substance – of audit committee functioning. ^
Resumo:
A comprehensive investigation of sensitive ecosystems in South Florida with the main goal of determining the identity, spatial distribution, and sources of both organic biocides and trace elements in different environmental compartments is reported. This study presents the development and validation of a fractionation and isolation method of twelve polar acidic herbicides commonly applied in the vicinity of the study areas, including e.g. 2,4-D, MCPA, dichlorprop, mecroprop, picloram in surface water. Solid phase extraction (SPE) was used to isolate the analytes from abiotic matrices containing large amounts of dissolved organic material. Atmospheric-pressure ionization (API) with electrospray ionization in negative mode (ESP-) in a Quadrupole Ion Trap mass spectrometer was used to perform the characterization of the herbicides of interest. ^ The application of Laser Ablation-ICP-MS methodology in the analysis of soils and sediments is reported in this study. The analytical performance of the method was evaluated on certified standards and real soil and sediment samples. Residential soils were analyzed to evaluate feasibility of using the powerful technique as a routine and rapid method to monitor potential contaminated sites. Forty eight sediments were also collected from semi pristine areas in South Florida to conduct screening of baseline levels of bioavailable elements in support of risk evaluation. The LA-ICP-MS data were used to perform a statistical evaluation of the elemental composition as a tool for environmental forensics. ^ A LA-ICP-MS protocol was also developed and optimized for the elemental analysis of a wide range of elements in polymeric filters containing atmospheric dust. A quantitative strategy based on internal and external standards allowed for a rapid determination of airborne trace elements in filters containing both contemporary African dust and local dust emissions. These distributions were used to qualitative and quantitative assess differences of composition and to establish provenance and fluxes to protected regional ecosystems such as coral reefs and national parks. ^
Resumo:
In my dissertation, I examine factors associated with firms’ submission of auditor selection for shareholder ratification and test if shareholder ratification of auditor selection is associated with the extent of price competition in the audit market (as measured by audit fees) and audit quality (as measured by clients’ earnings management). The dissertation is motivated from the recent recommendation of the U.S. Treasury’s Advisory Committee on Auditing Profession (ACAP) regarding the submission of auditor selection for shareholder ratification votes. The ACAP suggests that this practice may improve the competition in the audit market; yet, there is no empirical evidence supporting the ACAP’s recommendation. My dissertation attempts to fill the gap in the literature on an issue of current interest to the auditing profession. I find that firm size, CEO-Chair duality, insider ownership and institutional ownership are associated with the submission of auditor selection for shareholder ratification vote. However, I do not find an association between audit committee variables and the submission of auditor selection for shareholder ratification vote. The second essay investigates the association between auditor ratification and audit fees. Audit fees are higher in firms that submit auditor selection for shareholder ratification. The finding is not consistent with the increased price competition predicted by the ACAP. The third essay of my dissertation examine whether the submission of auditor selection for shareholder ratification is associated with earnings management. I find that firms that submit auditor selection for shareholder ratification are more likely to have lower level of earnings management. Overall, the results suggest that the same factors that are associated with higher quality monitoring also may be associated with the submission of auditor selection for shareholder ratification vote. The results call into question the one-size-fits-all approach recommended by the ACAP.
Resumo:
There is limited scientific knowledge on the composition of human odor from different biological specimens and the effect that physiological and psychological health conditions could have on them. There is currently no direct comparison of the volatile organic compounds (VOCs) emanating from different biological specimens collected from healthy individuals as well as individuals with certain diagnosed medical conditions. Therefore the question of matching VOCs present in human odor across various biological samples and across health statuses remains unanswered. The main purpose of this study was to use analytical instrumental methods to compare the VOCs from different biological specimens from the same individual and to compare the populations evaluated in this project. The goals of this study were to utilize headspace solid-phase microextraction gas chromatography mass spectrometry (HS-SPME-GC/MS) to evaluate its potential for profiling VOCs from specimens collected using standard forensic and medical methods over three different populations: healthy group with no diagnosed medical or psychological condition, one group with diagnosed type 2 diabetes, and one group with diagnosed major depressive disorder. The pre-treatment methods of collection materials developed for the study allowed for the removal of targeted VOCs from the sampling kits prior to sampling, extraction and analysis. Optimized SPME-GC/MS conditions has been demonstrated to be capable of sampling, identifying and differentiating the VOCs present in the five biological specimens collected from different subjects and yielded excellent detection limits for the VOCs from buccal swab, breath, blood, and urine with average limits of detection of 8.3 ng. Visual, Spearman rank correlation, and PCA comparisons of the most abundant and frequent VOCs from each specimen demonstrated that each specimen has characteristic VOCs that allow them to be differentiated for both healthy and diseased individuals. Preliminary comparisons of VOC profiles of healthy individuals, patients with type 2 diabetes, and patients with major depressive disorder revealed compounds that could be used as potential biomarkers to differentiate between healthy and diseased individuals. Finally, a human biological specimen compound database has been created compiling the volatile compounds present in the emanations of human hand odor, oral fluids, breath, blood, and urine.
Resumo:
Actions by both private sector organizations and legislators in recent years have highlighted the importance of the audit committee of the board of directors of corporations in the financial reporting process. For example, the Sarbanes Oxley Act of 2002 has multiple sections that deal with the composition and functioning of audit committees. My dissertation examines multiple issues related to the composition of audit committees. In the first two parts of my dissertation, I examine the stock market reactions to disclosures of audit committee appointments and departures in the 8-Ks filed with the SEC during 2008 and 2009. I find that there is a positive stock market reaction to the appointment of audit committee directors who are financial experts. The second essay investigates the cumulative abnormal return to departure of audit committee directors. I find that when an accounting expert leaves the audit committee, the market reaction is significantly negative. These results are consistent with regulators’ concerns related to having directors with audit, accounting and other financial expertise on corporate audit committees. The third essay of my dissertation examines the changes in audit committee composition in the last decade. I find that while the increase in audit committee size is relatively modest, there has been a significant increase in the number of audit committee experts and the frequency of audit committee meetings over the past decade; interestingly, such increase in the number of meetings has persisted even after the media focus on the auditing profession, in the immediate aftermath of the Enron and Andersen failures, have waned. My results show that audit committee composition and its role continues to evolve with regulatory and other corporate governance related changes.
Resumo:
Audit reporting lag continues to remain an issue of significant interest to regulators, financial statement users, public companies, and auditors. The SEC has recently acted to reduce the deadline for filing annual and quarterly financial statements. Such focus on audit reporting lag arises because, as noted by the Financial Accounting Standards Board, relevance and reliability are the two primary qualities of accounting information; and, to be relevant, information has to be timely. In my dissertation, I examine three issues related to the audit report lag. The first essay focuses on the association between audit report lag and the meeting or beating of earnings benchmarks. I do not find any association between audit report lag and just meeting or beating earnings benchmarks. However, I find that longer audit report lag is negatively associated with the probability of using discretionary accruals to meet or beat earnings benchmarks. We can infer from these results that audit effort, for which audit report lag is a proxy, reduces earnings management. The second part of my dissertation examines the association between types of auditor changes and audit report lag. I find that the resignation of an auditor is associated longer audit report lag compared to the dismissal of an auditor. I also find a significant positive association between the disclosure of a reportable event and audit report lag. The third part of my dissertation investigates the association between senior executive changes and audit report lag. I find that audit report lag is longer when client firms have a new CEO or CFO. Further, I find that audit report lag is longer when the new executive is someone from outside the firm. These results provide empirical evidence about the importance of senior management in the financial reporting process.
Resumo:
There are situations in which it is very important to quickly and positively identify an individual. Examples include suspects detained in the neighborhood of a bombing or terrorist incident, individuals detained attempting to enter or leave the country, and victims of mass disasters. Systems utilized for these purposes must be fast, portable, and easy to maintain. The goal of this project was to develop an ultra fast, direct PCR method for forensic genotyping of oral swabs. The procedure developed eliminates the need for cellular digestion and extraction of the sample by performing those steps in the PCR tube itself. Then, special high-speed polymerases are added which are capable of amplifying a newly developed 7 loci multiplex in under 16 minutes. Following the amplification, a postage stamp sized microfluidic device equipped with specially designed entangled polymer separation matrix, yields a complete genotype in 80 seconds. The entire process is rapid and reliable, reducing the time from sample to genotype from 1-2 days to under 20 minutes. Operation requires minimal equipment and can be easily performed with a small high-speed thermal-cycler, reagents, and a microfluidic device with a laptop. The system was optimized and validated using a number of test parameters and a small test population. The overall precision was better than 0.17 bp and provided a power of discrimination greater than 1 in 106. The small footprint, and ease of use will permit this system to be an effective tool to quickly screen and identify individuals detained at ports of entry, police stations and remote locations. The system is robust, portable and demonstrates to the forensic community a simple solution to the problem of rapid determination of genetic identity.
Resumo:
Human scent, or the volatile organic compounds (VOCs) produced by an individual, has been recognized as a biometric measurement because of the distinct variations in both the presence and abundance of these VOCs between individuals. In forensic science, human scent has been used as a form of associative evidence by linking a suspect to a scene/object through the use of human scent discriminating canines. The scent most often collected and used with these specially trained canines is from the hands because a majority of the evidence collected is likely to have been handled by the suspect. However, the scents from other biological specimens, especially those that are likely to be present at scenes of violent crimes, have yet to be explored. Hair, fingernails and saliva are examples of these types of specimens. ^ In this work, a headspace solid phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) technique was used for the identification of VOCs from hand odor, hair, fingernails and saliva. Sixty individuals were sampled and the profiles of the extracted VOCs were evaluated to assess whether they could be used for distinguishing individuals. Preliminary analysis of the biological specimens collected from an individual (intra-subject) showed that, though these materials have some VOCs in common, their overall chemical profile is different for each specimen type. Pair-wise comparisons, using Spearman Rank correlations, were made between the chemical profiles obtained from each subject, per a specimen type. Greater than 98.8% of the collected samples were distinguished from the subjects for all of the specimen types, demonstrating that these specimens can be used for distinguishing individuals. ^ Additionally, field trials were performed to determine the utility of these specimens as scent sources for human scent discriminating canines. Three trials were conducted to evaluate hair, fingernails and saliva in comparison to hand odor, which was considered the standard source of human odor. It was revealed that canines perform similarly to these alternative human scent sources as they do to hand odor implying that, though there are differences in the chemical profiles released by these specimens, they can still be used for the discrimination of individuals by trained canines.^
Resumo:
Hotel management is increasingly looking for ways to evaluate marketing effectiveness. A system is needed to assess objectives, strategies, and performance. The Marketing Audit provides a workable, worthwhile tool for managers to assess current performances and long-range goals.