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Forensic entomology is an important field of forensic science that utilizes insect evidence in criminal investigations. Blow flies (Diptera: Calliphoridae) are among the first colonizers of remains and are therefore frequently used in determining the minimum postmortem interval (mPMI). Blow fly development, however, is influenced by a variety of factors including temperature and feeding substrate type. Unfortunately, dietary fat content remains an understudied factor on the development process, which is problematic given the relatively high rates of obesity in the United States. To study the effects of fat content on blow fly development we investigated the survivorship, adult weight and development of Lucilia sericata (Meigen; Diptera: Calliphoridae) and Phormia regina (Meigen; Diptera: Calliphoridae) on ground beef with a 10%, 20%, or 27% fat content. As fat content increased, survivorship decreased across both species with P. regina being significantly impacted. While P. regina adults were generally larger than L. sericata across all fat levels, only L. sericata demonstrated a significant (P < 0.05) difference in weight by sex. Average total development times for P. regina are comparable to averages published in other literature. Average total development times for L. sericata, however, were nearly 50 hours higher. These findings provide insight on the effect of fat content on blow fly development, a factor that should be considered when estimating a mPMI. By understanding how fat levels affect the survivorship and development of the species studied here, we can begin improving the practice of insect evidence analysis in casework.
Down syndrome (DS) is a common genetic developmental disorder characterized by the trisomy of chromosome 21 (Hsa21). All individuals with DS have some kind of intellectual disability, associated with dysfunction in cognition-related structures, including the frontal cortex. Studies have examined developmental changes in the frontal cortex during prenatal stages in DS, however little is known about cortical lamination and neuronal differentiation in postnatal periods in this neurodevelopmental disorder. Therefore, we examined the quantitative and qualitative distribution of neuronal profiles containing the neuronal migration protein doublecortin (DCX), the non-phosphorylated high-molecular-weight neurofilament SMI-32, the calcium-binding proteins calbindin D-28K (Calb), calretinin (Calr), and parvalbumin (Parv), as well as human β-amyloid and APP (6E10), Aβ1-42, and phospho-tau (CP-13) in the supragranular (SG, II/III) and infragranular (IG, V/VI) layers in the DS postnatal frontal cortex compared to neurotypically developing (NTD) controls from ages 28 weeks to 196.4 weeks using immunohistochemistry. Furthermore, cortical lamination was evaluated using thionin, a Nissl stain. We found DCX-immunoreactive (-ir) cells in both the SG and IG layers in younger cases, but not in the oldest cases in both groups. Strong expression of SMI-32 immunoreactivity was observed in pyramidal cells in layers III and V in the oldest cases in both groups, however SMI-32-ir cells appeared much earlier in NTD compared to DS. We found small and fusiform Calb-ir cells in the younger cases (28 to 44 weeks), while in the oldest cases, Calb immunoreactivity was also found in pyramidal cells. Calr-ir cells appeared earlier in DS at 32 weeks compared to NTD at 44 weeks, however both groups showed large bipolar fusiform-shaped Calr-ir cells in the oldest cases. Diffuse APP/Aβ-ir plaque-like accumulations were found in the frontal cortex grey and white matter at all ages, but no Aβ1-42 immunoreactivity was detected in any case. Furthermore, neuropil (but not cellular) granular CP-13 immunostaining was seen in layer I only at 41 weeks NTD and 33 weeks DS. Cell counts show a significantly higher cell number in SG compared to IG for all the neuronal markers in both groups, except in Calb and SMI-32. In NTD, age and brain weight showed the strongest correlations with all cellular counts, except in thionin where DS had a stronger negative correlation with age and brain weight compared to NTD. In addition, height and body weight showed a strong negative correlation in NTD with the migration and neurogenesis marker DCX. These findings suggest that trisomy 21 affects the postnatal frontal cortex lamination, neuronal migration<br/>eurogenesis, and differentiation of projection pyramidal cells and interneurons, which contribute to the disruption of the local and projection inhibitory and excitatory circuitries that may underlie the cognitive disabilities in DS.
Curiosity has been linked with many benefits, including increased overall well-being (Lydon-Staley et al., 2020) and greater academic achievement (Gottfried et al., 2016). The value that children place on learning new things and exploring novel ideas is unrivaled by older individuals. However, little research has been conducted to examine how parents may be able to help foster their children’s curiosity in a way that teaches them how to effectively search for and synthesize information. This paper aims to determine how parents’ language during a storybook task is related to their children’s strategy to collect rewards during a search game. Preliminary results suggest that parents may be able to encourage more effective search by asking more close-ended questions. These findings provide insight into how parents and guardians may be able to encourage their children to become better adept at searching for information by taking in clues about their environment and modifying their behavior to maximize their efforts.
The purpose of this paper is to examine cross-cultural differences between the United States and Turkey by coding multiple dimensions, such as parental intrusiveness, child persistence, and various others. The main research questions of this paper were as follows: (1) How does parental intrusiveness vary by country? (2) How does child persistence vary by country? and (3) Are parental intrusiveness and child persistence correlated, and if so, what is the direction of the correlation? The hypotheses were that (1) Turkish parents would score higher on parental intrusiveness, (2) American children would show higher levels of persistence, and (3) Parental intrusiveness and child persistence are correlated, with higher levels of parental intrusiveness resulting in lower levels of child persistence. While all of the hypotheses were supported with statistically significant results, it was found that in the U.S., higher parental intrusiveness does result in lower levels of child persistence, but in Turkey, parental intrusiveness was not a predictor of child persistence. The findings are therefore able to support cross-cultural differences in the correlation between parental intrusiveness and child persistence.
Beginning in the early 1990s, nuclear forensic science is a relatively young field that focuses on “re-establishing the history of nuclear material of unknown origin” (Mayer, et al. 2010, p. 1). Specifically, investigators compare these unknown materials, pre-detonation in this case, based on their characteristics and process history (Mayer, et al. 2010, p. 1). In 2010, the Committee of Nuclear Forensics made ten recommendations on the procedures that could lead to improvement in investigation methods. In particular, this paper discusses Recommendation 6: “The nuclear forensics community should develop and adhere to standards and procedures that are rooted in the applicable underlying principles that have been recommended for modern forensic science, including calibration using reference standards; cross-comparison with other methods; inter-laboratory comparisons; and identification, propagation, and characterization of uncertainties'' (Committee of Nuclear Forensics, 2010, p. 11). The main objective of this paper is to compile a literature review to determine how this recommendation was followed, if at all, and produce a list of suggestions that could complement any effort towards the improvement of the field. Out of the methods recommended, that which has fostered the most growth has been cross-comparison. For example, the need for human supervision has decreased, which has decreased the need for human error (Reading, et al., 2017, p. 6013). However, areas that would benefit from development are increasing the number of disciplines in the field (Croudace, et al., 2016, p. 128). These conclusions provided the basis for improvements to other existing studies like DNA and fingerprinting.
Mitigation banks are a tool created to mitigate and compensate for negative impacts on the environment resulting from man made activities, especially damage caused to endangered wildlife, plants, and wetland ecosystems. The main objective of creating the system of mitigation banks is to achieve environmental equilibrium, meaning “No Net Loss” to all environmental functions. This means damage to one area is compensated for in another area of like-kind through restoration. There is great controversy surrounding this claim. There is a system of debits and credits to ensure ecological loss from development is preceded by restoration of a similar ecology and function. Wetland mitigation banks are the focus for the purpose of research. Background and benefits will be given first, followed by threats, issues, solutions and a personal experience with mitigation banks.