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Assessment of Virus-Induced Myocarditis in Human Heart Tissue Samples
Get PDFThe heart is a major organ whose function is to transport nutrients and waste throughout the body. This organ can become infected by pathogens, such as viruses, bacteria, or parasites. Infection of the middle heart layer, or myocardium, is often caused by a viral agent. This disease has three stages: viral infiltration, adaptive immune system activation, and finally either viral clearance or cardiac cell remodeling. During this process the immune system will begin to secrete cytokines, which are signaling molecules that alert other members of the immune pathways, and also participate in cardiac remodeling. Evaluating the correlation between the cytokine expression levels with the viruses present in cardiomyopathy-positive heart tissue samples can lead to a better understanding of cardiac disease process, and aid in the development of new diagnostic tools.
In order to accomplish this study nucleic acid (DNA and RNA) from heart tissues obtained from cardiomyopathy-positive samples, as well as donor samples, was isolated. The DNA was then used in a PCR reaction with viral primers corresponding to DNA viruses. Next, RNA was used to synthesize cDNA. With cDNA made two types of analyses took place: a PCR with primers specific to RNA viruses was performed to identify viral genomes, and a qPCR assay was done to evaluate the expression levels of cytokines.
The most common viruses identified in the study were HRSV, Herpesviruses 5/7, and Hepatitis-C virus. The virus that was least prevalent was Coxsackievirus-B3. The analysis of cytokine expression profiles and genes involved in cardiac remodeling revealed that samples BIF28 and 48CAF had the highest expression levels of immune system, and cardiac, markers. The two markers with increased expression levels were Tnnt2 and TGF-β. When the cytokine expression levels were compared for each of the three heart layers (endocardium, epicardium, and myocardium) it was seen the epicardium had the highest expression levels, suggesting highest levels of inflammation. In sum, the generated data revealed a correlation between viral infection and the degree of heart inflammation. Interestingly, based on samples analyzed in this study, I showed that distinct layers of the heart can have various inflammatory profiles, suggesting different levels of cardiac damage. Follow up studies will help delineate the association of viral infection of cardiac muscle and inflammation, which may help develop better diagnostic tools
Evaluation of the Effect of the Humic Acid Inhibitor on Forensic Genetic Investigations of Human Skeletal Remains
Get PDFPostmortem survival of DNA in human skeletal remains occurs due to the compact microstructure of the skeleton and its ability to provide a strong, protective physical barrier to environmental insults. On a molecular level, DNA preservation in bones/teeth involves electrostatic interactions between the negatively-charged DNA backbone and positively charged calcium residues in hydroxyapatite, the latter of which is one of the main components of bone microstructure. Despite these protections, over time endogenous DNA becomes damaged, limiting our ability to detect it and affecting its utility in making a positive identification. Hence, forensic genetic investigations of unidentified human remains (UHRs) are limited by the quality, quantity, and purity of DNA recovered.
Significant damage or alteration to the molecular structure of DNA is problematic because polymerases stall at damaged/altered sites, preventing PCR amplification (and subsequent analysis) of target loci. Concurrent complications arise from endogenous and/or environmental inhibitors that tend to co-extract with DNA and impede or completely block downstream polymerase-based reactions. One of the most pervasive PCR inhibitors encountered in skeletal remains cases is humic acid (HA), an acid found in all soils worldwide, in varying concentrations. Purification of endogenous DNA away from such an inhibitor is crucial for both the quantification and PCR amplification steps in the forensic DNA workflow.
The purpose of this study was to demonstrate the effect of co-extracted humic acid (HA) on quantitative PCR (qPCR), the method used to determine the amount of DNA recovered from evidentiary samples. The inhibitory effects of six different HA solutions (5.0mg/mL, 2.5mg/mL, 1.25mg/mL, 0.625mg/mL, 0.3125mg/mL, 0.156mg/mL) on six different DNA concentrations (50ng/µL, 5ng/µL, 0.5ng/µL, 0.05ng/µL, 0.02ng/µL, 0.005ng/µL) were explored. At the three highest HA concentrations (5.0mg/mL, 2.5mg/mL, 1.25mg/mL), complete qPCR inhibition was observed for all DNA concentrations. At the lowest three HA concentrations (0.625mg/mL, 0.3125mg/mL, 0.156mg/mL), DNA polymerases in the qPCR assay were able to work, but with lower efficiency. Even in the presence of these low HA concentrations, accuracy of DNA quantification was reduced (i.e., the qPCR assay under-estimated DNA quantities present for all samples). This under-estimation could substantially impact downstream PCR amplification of STR loci and may result in partial DNA profiles or no DNA profiles. Purification of DNA from the bone matrix is essential. The results of this study demonstrate the importance of effective DNA extraction and removal of inhibitors to maximize chances of DNA typing success
Financial Frictions and Macroeconomy During Financial Crises: A Bayesian DSGE Assessment
Get PDFThe recent global financial crisis and the Eurozone sovereign default have rekindled the debate on the interactions between the real sector and the financial sphere. The present paper provides an assessment of the role of financial frictions on business cycles in Canada, the Euro Area, the U.K., and the U.S. during these recent financial crises using an extension of the DSGE methodology described by Merola (2015). The main goal is to examine whether and the extent to which those crises enhanced the contribution of financial frictions in driving macroeconomic fluctuations. The models’ properties are examined with posteriors distributions, variance decomposition, and historical decomposition. Posteriors distributions show that the role of real shocks in driving macroeconomic fluctuations decrease with the incorporation of financial frictions in the core DSGE model. Variance decomposition shows that financial frictions and financial shocks affect the business cycle through investment. The empirical estimates also suggest that the contribution of financial frictions and financial shocks in driving investment increases during the global financial crisis
Cheating from a Distance: An Examination of Academic Dishonesty Among University Students
Get PDFAcademic dishonesty among college students has been an enduring issue within higher education. While prior research has explored this issue, the recent global pandemic has shifted collegiate demographics dramatically, particularly within online courses. As a result, previous findings may prove less applicable, warranting new research into student cheating within this current educational landscape. Given these new enrollment trends, this study investigated intentions to cheat in traditional and online class settings, and for criminal justice and non-criminal justice majors. Utilizing principles of rational choice theory, other factors related to academic misconduct also were explored.
For this study, original data were collected from one institution in the New England region of the United States. An online questionnaire was emailed to approximately 6,900 undergraduate and graduate students, resulting in 1,084 total submitted surveys. Using the email link, participants were assigned randomly to treatment and control groups based on course modalities. More precisely, 553 students responded to prompts related to cheating in traditional courses, while 531 students answered similar questions related to online courses. Using the obtained data, a series of univariate, bivariate, and multivariate statistical results were produced.
The results of the statistical models yielded numerous significant findings regarding influences on academic dishonesty among college students. Among these results, three findings were especially noteworthy. First, intentions to cheat appear relatively equivalent among traditional and online students. While certain distinctions were observed among online students, overall cheating behaviors were quite similar across the course groups. Second, criminal justice majors reported more concerning levels of academic misconduct than initially suspected. While cheating appeared similar across all academic majors, criminal justice students reported higher intentions to cheat in certain scenarios. Finally, perceptions of cheating benefits yielded the most consistently significant results among the rational choice variables. Overall, academic dishonesty was more likely to occur when such behaviors were perceived to positively affect a student’s academic, peer, and/or familial goals. This study reveals the significant factors influencing the likelihood of academic dishonesty, followed by a discussion of policy implications to remedy this issue and suggestions for future research
Analysis of Benthic Infauna in Long Island Sound using GIS Spatial Techniques
No full textGeographic Information Systems (GIS) are now regularly used in a variety of sectors including public health, city planning, and emergency management planning. Environmental scientists and managers also utilize GIS as a framework for gathering, managing, and analyzing terrestrial ecological data. More recently, GIS has been used for characterizing seafloor habitats and the communities within those habitats. Less known and used among marine ecologists is the Spatial Statistics toolbox within ESRI ArcGIS software. These tools can be used to determine spatial patterns and their statistical significance for several types of data associated within benthic communities. The goal of this study was threefold. Firstly, to evaluate the effectiveness of a variety of spatial statistics tools including Getis-Ord Gi Hot spot, Cluster-Outlier analysis (Anselin Local Morans I), Spatial Autocorrelation (Global Moran\u27s I), Incremental Spatial Autocorrelation and Grouping Analysis, for understanding benthic communities in the eastern area of Long Island Sound (LIS); secondly, to identify which analyses provided the most useful information on the spatial patterns and scales of benthic infaunal community characteristics; and to use the analyses to inform what factors could be driving the spatial patterns identified. The results show that, in general, as the distance grouping classes among sample sites increased, the number of statistically significant hot spots and cluster-outliers also increased. For taxonomic richness and total abundance, analyses indicated that environmental and ecological factors that vary on a spatial scale of 1,500 and 2,500 m may be driving infaunal communities in the eastern portion of Long Island Sound, from the Connecticut River through Fishers Island Sound. Analyses of diversity data suggested that spatial statistical routines (in ArcGIS and otherwise) might not be sensitive enough to pick up spatially significant patterns due to the v narrow range of values in these data. Results from the grouping (clustering) analysis for benthic communities indicated that community types were spatial variable but that large- scale trends were identified, with generally differing community types in the western, central and most eastern portions of the study area. However, the relative similarity of the communities depended on the number of groups designated in the analysis parameters. The spatial statistics toolbox in ArcGIS provides a powerful set of analyses that can help researchers gain additional insights into seafloor habitats and their associated benthic communities that compliment more regularly employed analysis procedures, and it turn inform management and conservation efforts
Personality Dimensions of Male and Female Law Enforcement Recruits Related to Academy Success
Get PDFResearch has found that male and female law enforcement recruits complete academy training at different rates, with female recruits typically completing at lower rates than male recruits. While the literature on the topic demonstrates a variety of training characteristics that explain some of the difference, it is possible that typical personality differences between men and women play a role in some of the unexplained disparities in academy passing rates. This study attempted to discern differences between personality characteristics among male and female academy recruits using survey data from two major metropolitan law enforcement academies. It was hypothesized that male cadets would score higher than female cadets in personality traits that contribute to positive outcomes in the academy. The results demonstrated statistical evidence that women felt they had to exert more effort than men and felt less support than men from both their supervisors and from their families. However, the majority of personality constructs examined exhibited no significant differences between male and female cadets. Future research should further investigate differences in effort and support between male and female cadets to better understand differences in rates of completion of academy training
A User-Centric Mechanism for Sequentially Releasing Graph Datasets under Blowfish Privacy
No full textIn this article, we present a privacy-preserving technique for user-centric multi-release graphs. Our technique consists of sequentially releasing anonymized versions of these graphs under Blowfish Privacy. To do so, we introduce a graph model that is augmented with a time dimension and sampled at discrete time steps. We show that the direct application of state-of-the-art privacy-preserving Differential Private techniques is weak against background knowledge attacker models. We present different scenarios where randomizing separate releases independently is vulnerable to correlation attacks. Our method is inspired by Differential Privacy (DP) and its extension Blowfish Privacy (BP). To validate it, we show its effectiveness as well as its utility by experimental simulations
Amino Acid Composition Analysis as a Means to Differentiate Hair Samples from Individuals of Similar Demographics and the Effect of Hair Treatments
Get PDFHair is a forensically-relevant exhibit due to its ability to be shed, torn, or transferred during a crime. Current forensic hair analysis includes microscopic hair comparison and mitochondrial or nuclear DNA analyses, each with limitations. Novel methods, such as those evaluated herein, have potential to complement conventional techniques. These include evaluating functional groups with infrared (IR) spectroscopy, elements with laser induced breakdown spectroscopy (LIBS), and amino acid ratios with gas chromatography- mass spectrometry (GC-MS). Hair from two demographically similar individuals was divided into three sample groups per individual: untreated, bleached, and dyed. Spectral differences between individuals and treatments were evaluated with IR. Five of eleven bands differed between individuals, and seven bands differed after treatment. LIBS analysis revealed calcium, potassium, and sodium to be significantly different among individuals. Decreases in carbon, nitrogen, oxygen, and hydrogen were observed after treatments. Six derivatized amino acids were identified with GC-MS to produce fifteen amino acid ratios. One ratio was found to be significantly different among individuals. Additional significant differences would likely surface with retesting. Complications with GC-MS made comparisons between individuals and treatments difficult. individual 2 displayed lower variances, so comparisons between treatments were based on their data. For individual 2, three amino acid ratios were found to be significantly different after bleaching, while none were after dyeing. Variances in GC-MS analysis made the amino acid ratio stability after treatments difficult to establish. Further research is required to better understand the effects of chemical treatments on elements, functional groups, and amino acids
No One is Above the Law: Public Perception of Prosecutorial Misconduct\u27s Influence on Wrongful Convictions
Get PDFWrongful convictions pose a large threat to the integrity of the United States criminal justice system. While there are many known causes of wrongful convictions, such as eyewitness misidentification, ineffective counsel, and false confessions, the most egregious cause is prosecutorial misconduct. According to the National Registry of Exonerations, prosecutorial misconduct has been found in roughly half of the exonerations listed in the registry. Prosecutors have a tremendous amount of power in the criminal justice system through determining plea deals, obtainment of evidence, disclosure of evidence to the defense, and many more. Studies have been conducted that reveal the occurrence of prosecutorial misconduct, yet very little has been done to correct such misconduct. This study addressed the prevalence of this topic and basic knowledge of United States citizens, specifically legal professionals on prosecutorial misconduct. This study found that perceptions of criminal justice system fairness had the most significance when determining prosecutorial liability, accountability, preventative efforts, regulation and support for overall reform
Extraction of Human DNA from Soil in a Simulated Clandestine Grave
Get PDFLocard’s Exchange Principle states that “every contact leaves a trace.” The same principle applies when a perpetrator of a homicide decides to bury a victim in a clandestine grave. If a perpetrator originally buried a murder victim in haste to prevent discovery and then decided to later move the victim’s body to a remote location for disposal, decomposition fluids from the victim’s body (which contain cellular material and therefore DNA) would remain in the surrounding grave soil at the original burial site. It is possible that investigators could: 1) prove that a human body had once laid in that location (as opposed to animal remains), and 2) determine the identity of the victim via forensic DNA typing of the cellular remnants and body fluids left behind in the soil.
In this case study, a simulated clandestine grave was created in the laboratory using human remains (femur) from a previous cemetery exhumation. The remains were donated for research and had not been embalmed prior to burial. Over a 4-week period, the remaining soft tissue attached to the femur was allowed to decompose naturally; soil samples from directly underneath each femur section were collected at 1-week, 2-week, 3- week, and 4-week intervals. Two different DNA extractions methods (silica-based and organic) were performed in an attempt to recover human DNA from decomposition fluids in the soil. DNA quantities recovered from each soil sample aliquot were determined using a human-DNA-specific quantification kit and real-time (quantitative) PCR. The organic extraction method yielded higher amounts of human nuclear DNA for downstream STR genotyping than silica-based DNA extraction. The average DNA quantities (ng) recovered using organic and silica-based DNA extraction were 1.6929 ng and 0.0445 ng, respectively. Although attempts were undertaken to purify DNA and remove PCR inhibitors from the soil (e.g.,acids, fulvic acids), qPCR results indicated that many samples were still exhibiting signs of inhibition. Although this study demonstrates proof-of-concept that human DNA can be recovered from decomposition fluids in soil underneath human remains in clandestine graves, future research efforts should focus on improving DNA extraction approaches that would better facilitate removal of soil-derived inhibitor