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1.
This research demonstrates the value of laser scanning confocal microscopy (LSCM) as a research tool in osteological studies, and diagenetic studies in particular. LSCM combines properties of light and scanning electron microscopy using laser light to excite fluorophores throughout the z-axis, developing a 3-D image. Using differential staining and selecting for specific wavelengths of light, one can image targeted materials. This research is divided into two parts: visualizing bone structures such as proteins and their decompositional products and visualizing diagenesis. Part one of this study utilized pig bones as a means of testing the overall ability of LSCM to fluoresce bone. Twenty-three samples were imaged, including 13 samples from a decompositional study conducted 5 years previous, and 10 “fresh” samples collected from a commercial butcher. This part of the study determined that protein and organic components of the bone could be fluoresced and diagenetic alteration could be imaged. The second part of the study used human samples as a means of imaging and mapping diagenetic alterations. The second part of the study used 13 samples, including 4 clinical, 7 ancient, and 2 modern controls. The pig study used Basic Fuchsin and SlowFade Gold stains, while the human study used toluidine blue. Images were also taken with unstained elements. The results of the non-human study found that a fresh bone fluoresced differently than that of a 5-year subset, while the results of the human study confirmed these findings and determined that the bone diagenesis can be mapped using LSCM. 相似文献
2.
Selena McKay-Davis M.F.S. Tharinia Robinson Ph.D. Ismail M. Sebetan M.D. Ph.D. Paul Stein Ph.D. 《Journal of forensic sciences》2020,65(6):2065-2070
Forensic Technicians provide crime scene investigation services and are exposed to stressful violent crimes, motor vehicle accidents, biological or chemical hazards, and other appalling imagery. Forensic Technicians would likely experience physical and psychological stress after exposure to trauma, and security vulnerabilities similar to Sworn Police Officers. The perceived availability of mental health resources, job-related physical, psychological stress, and traumatic experiences of both Forensic Technicians and Sworn Police Officers from California law enforcement agencies were investigated using a self-reported survey. Responses were evaluated for any significant differences in the perceived stress, job-related physical stress, and resulting psychological impact affecting the participants. The survey contained a mix of True/False, Circle/Check the Appropriate Box, or Likert Scale (1–5) responses. The results were evaluated statistically and discussed. Results indicated Sworn Police Officers and Forensic Technicians have different on-duty stress levels, but similar off-duty stress levels. Nearly two-thirds of 54 job-related stressors were not significantly different between the two occupations. However, Forensic Technicians reported more adverse effects in 17 physical and psychological job-related activities compared with Sworn Police Officers. Forensic Technicians reported lower awareness levels and availability of agency mental health support services than were reported by Sworn Police Officers. This study reports for the first time an unexpected outcome that perceived and job-related psychological stress is greater for Forensic Technicians than Sworn Police Officers. Possible reasons for this disparity will be discussed as well as stress management tools that should be implemented to reduce health risk factors for both career professionals as well as increase public safety. 相似文献
3.
The complexity of the modern information ecosystem raises many questions for public organizations. In the context of emergency management, information (such as warning messages) is communicated not only from a source of authority to the public but also between members of the public. The authors use a series of storms that affected Oklahoma in the spring of 2016 to test propositions related to how information about tornado warnings reached the public and who received and shared information about the storm, as well as to identify how gender and age mediate the influence that exposure to an extreme weather event has on the sharing of this information. Overall, the authors find that reported exposure to a tornado increases information sharing through a variety of media and technology. The effect of the tornado erases the otherwise present gender gap in sharing information, while it has little effect on the media platforms that are most popular among older respondents. 相似文献
4.
Public Choice - We present the approach to comparative economic development of Why Nations Fail. Economic prosperity requires inclusive economic institutions—those which create broad based... 相似文献
5.
Dorothy L. Espelage Kathleen C. Basile Ruth W. Leemis Tracy N. Hipp Jordan P. Davis 《Journal of youth and adolescence》2018,47(9):1880-1893
The Bully-Sexual Violence Pathway theory has indicated that bullying perpetration predicts sexual violence perpetration among males and females over time in middle school, and that homophobic name-calling perpetration moderates that association among males. In this study, the Bully-Sexual Violence Pathway theory was tested across early to late adolescence. Participants included 3549 students from four Midwestern middle schools and six high schools. Surveys were administered across six time points from Spring 2008 to Spring 2013. At baseline, the sample was 32.2% White, 46.2% African American, 5.4% Hispanic, and 10.2% other. The sample was 50.2% female. The findings reveal that late middle school homophobic name-calling perpetration increased the odds of perpetrating sexual violence in high school among early middle school bullying male and female perpetrators, while homophobic name-calling victimization decreased the odds of high school sexual violence perpetration among females. The prevention of bullying and homophobic name-calling in middle school may prevent later sexual violence perpetration. 相似文献
6.
7.
Catherine P. Bradshaw Tracy Evian Waasdorp Asha Goldweber Sarah Lindstrom Johnson 《Journal of youth and adolescence》2013,42(2):220-234
Recent media attention has increased interest in behavioral, mental health, and academic correlates of involvement in bullying. Yet, there has not been much interest in investigating the co-occurrence of other health-risk behaviors, such as gang membership, weapon carrying, and substance use. The potential influence of contextual factors, such as youth ethnicity, urbanicity, and school characteristics, also has been overlooked in previous research. The current study examined different subtypes of involvement in bullying—as primarily a victim, as primarily a bully, as both a victim and bully, and no involvement—and the association with significant health-risk behaviors, including engaging in violence and substance use, as well as academic problems. The analyses use self-report data from 16,302 adolescents (50.3 % female, 62.2 % Caucasian, 37.8 % African American) enrolled in 52 high schools. A series of three-level HLM analyses revealed that bullies and bully/victims were generally at greatest of risk of being involved in violence, engaging in multiple types of substance use, and having academic problems. These findings extend prior research by emphasizing a potential link between involvement in bullying and multiple health-risk behaviors, particularly among urban and African American high school youth. 相似文献
8.
Asha Goldweber Tracy Evian Waasdorp Catherine P. Bradshaw 《Journal of youth and adolescence》2013,42(2):206-219
Research on the role of race and urbanicity in bullying involvement has been limited. The present study examined bullying involvement subgroups that relate to race, urbanicity, and the perceived reason for the bullying. Self-report data were collected from 10,254 middle school youth (49.8 % female; 62.4 % Caucasian, 19.0 % African American, and 5.6 % Hispanic) and latent class analyses were used to identify three subtypes of bullying involvement: low involvement (50 %), victim (31.3 %), and bully-victim (18.7 %). Irrespective of urbanicity (urban vs. non-urban), African American youth were more likely to be members of either the victim or bully-victim classes than the low involvement class. Further exploration of the community context suggested that urbanicity was associated with the increased likelihood of having been racially bullied. Urban bully-victims were also more likely to have been bullied about money than non-urban bully-victims. Findings underscore the importance of addressing both race and urbanicity for culturally sensitive prevention programming. 相似文献
9.
Tracy Llanera 《Critical Horizons》2017,18(3):281-288
Retrieving Realism renders the joint philosophical goals of Hubert Dreyfus and Charles Taylor into what is probably their final and most concise form. It has two main objectives: first, it aims to deconstruct the mediationalism that undergirds Western philosophy, and second, it endorses contact theory, or embodied/embedded coping, as an alternative. In this essay, I present the book’s most salient themes and reveal areas that are ripe for further philosophical consideration. I also direct the reader to the work’s genuine ontological challenge: how to come to grips with contact theory beyond the borders of epistemology. 相似文献
10.
Investigating the Potential of Fluorescent Fingerprint Powders as a Marker for Blow Fly Larvae (Diptera: Calliphoridae) 下载免费PDF全文
Jennifer Y. Rosati Ph.D. Scott D. Robinson B.Sc. Richard Devine 《Journal of forensic sciences》2015,60(3):653-658
Four fluorescent fingerprint powders (RedWop?, GreenWop?, Basic Yellow?, and Yellow Powder?) were evaluated as a marker for blow fly larvae. Administration methods included ingestion (high vs. low concentration) or topical. Ingestion of high concentrations of Basic Yellow? and RedWop? caused higher larval mortality. Basic Yellow? delayed development and adult emergence while RedWop? and Yellow Powder? had a significant effect on particular stages of development, however, emergence time was not altered. Optimal administration is through ingestion at low concentration levels (<10%) or topically, with GreenWop? demonstrating minimal adverse effects. Optimum wavelength for discrimination between powders was 450 nm. This research can aid in investigative training to increase visibility of larval and pupal blow flies. It can also be used in entomological studies to differentiate between larval blow flies (or other dipteran) species or individuals to further understand complex interactions and behavior during larval development. 相似文献