Trotter and Gleser's (1958) equations outperform Trotter and Gleser's (1952) equations in stature estimation of the US White males.

Trotter and Gleser presented two sets of stature estimation equations for the US White males in their 1952 and 1958 studies. Following Trotter's suggestion favouring the 1952 equations simply due to the smaller standard errors, the 1958 equations have been seldom used and have gone without additional systematic validation tests. This study aims to assess the performance of the Trotter and Gleser 1952, Trotter and Gleser 1958, and FORDISC equations for the White males in a quantitative and systematic way, particularly when applied to the WWII and Korean War casualties. In sum, 27 equations (7 from the 1952 study, 10 from the 1958 study, and 10 from FORDISC) were applied to the osteometric data of 240 accounted-for White male casualties of the WWII and Korean War. Then, the bias, accuracy, and Bayes factor for each set of stature estimates were calculated. The results show that, overall, Trotter and Gleser's 1958 equations outperform the 1952 and FORDISC equations in terms of all three measures. Particularly, the equations with higher Bayes factors produced stature estimates where distributions were closer to that of the reported statures than those with lower Bayes factors. When considering Bayes factors, the best performing equation was the "Radius" equation from the 1958 study (BF = 15.34) followed by the "Humerus+Radius" equation from FORDISC (BF = 14.42) and the "Fibula" equation from the 1958 study (BF = 13.82). The results of this study will provide researchers and practitioners applying the Trotter and Gleser stature estimation method with a practical guide for equation selection. Key Points: The performance of three stature estimation methods was compared quantitatively.Trotter and Gleser's (1952, 1958) and FORDISC White male equations were included.Overall, Trotter and Gleser's 1958 method outperformed the other methods.This study provides a practical guide for stature estimation equation selection.

Routine Mediastinal Drainage Fluid Culture for Early Diagnosis of Poststernotomy Mediastinitis.

BACKGROUND: Early diagnosis of poststernotomy mediastinitis (PSM) is challenging. Since 2016, we have routinely performed mediastinal drainage fluid culture (MDFC) in patients undergoing sternotomy. This study aimed to determine the utility of MDFC for early diagnosis of PSM. METHODS: Between November 2016 and April 2020, we conducted MDFC in 1,012 patients on the third postoperative day and prospectively observed for PSM occurrence for 3 months. If bacteria were identified, additional MDFC or blood culture was performed to reduce the possibility of false positives. Based on MDFC results, the decision for early treatment for PSM was at the attending physician's discretion. RESULTS: Bacteria were identified in MDFC of 29 patients, eight of whom subsequently developed PSM. Among 983 patients with negative MDFC, only 15 developed PSM. In multivariate analysis, previous sternotomy history and positive MDFC were predictors of PSM. Positive MDFC was regarded as true positive if (1) PSM occurred subsequently, and/or (2) the same bacteria were identified in additional MDFC/blood culture. Non-occurrence of PSM in the absence of antibiotic treatment was regarded as false-positive MDFC. The sensitivity, specificity, and positive and negative predictive values of routine MDFC for diagnosis of mediastinal infection were 46.4, 99.0, 56.5, and 98.5%, respectively. When categorizing cases with positive MDFC based on the identified bacteria, the positive predictive value was highest (76.9%) when Staphylococci were identified. CONCLUSION: Routine MDFC after sternotomy can facilitate early diagnosis of PSM. Early treatment for PSM may be indicated in patients in whom Staphylococci are identified in the MDFC.

A comparative analysis of Bayesian age-at-death estimations using three different priors and Suchey-Brooks standards.

This study addresses issues associated with limited access to reference skeletal collections and how it hampers regional methodological development. The study also investigates the effects of three different priors on age-at-death estimations of Koreans and quantifies the accuracy of Bayesian estimation compared to a non-Bayesian approach. CT scan images of pubic symphyses were scored following the Suchey-Brooks standards. We specifically examine Bayesian age-at-death estimations under an optimal scenario where both the likelihood and prior probability are derived from a target population of Korean origin. Three different priors (population, forensic, and uniform priors) are evaluated for their age estimation accuracy levels. The results showed that Korean males and females had discrepancies in skeletal aging rates only in certain phases. A similar trend was observed in the comparison of the original Suchey-Brooks and Korean sample aging rates. However, when final age estimates were computed based on an inadequate choice of a prior, the between-group differences may be minimized or even obscured. The uniform and forensic priors produced the most reasonable and unbiased estimates, while the uniform prior consistently provided open-ended estimates for the last phase. The population prior produced consistently higher estimates due to the high survivorship of Koreans. In addition, the original Suchey-Brooks standards persistently under-estimated ages for Korean males and females. Overall, when Bayesian age estimation is based on an informed prior that best matches the context of the case (forensic deaths in this study), there was increased accuracy of final age estimates compared to age estimates of other priors and the original Suchey-Brooks method.

Biodiversity of Forensically Relevant Blowflies (Diptera: Calliphoridae) at the Anthropology Research Facility in Knoxville, Tennessee, USA.

Understanding the biodiversity and distribution of forensically relevant blowflies (Diptera: Calliphoridae) in a region can aid in legal investigations when insects are associated with remains. For this purpose, we conducted a 14-month-long blowfly survey at the Anthropology Research Facility (ARF) of the University of Tennessee in Knoxville, Tennessee. Traps baited with pork kidney were deployed for 24 h twice a month throughout the study. A total of 3180 adult blowflies were collected, comprising 13 species from 7 genera. Phormia regina (Meigen) and Lucilia coeruleiviridis (Macquart) were the predominant species collected from this survey, with collections representing 65.9% and 20.6%of total flies captured, respectively. In addition to relative abundance, we investigated blowfly community composition, species abundance, richness, and diversity by season. One state record was identified, with adult Protophormia terraenovae (Robineau-Desvoidy) being collected for the first time in Tennessee. Additionally, an earlier record of Chrysomya megacephala (Fabricius) in Tennessee was noted. These findings can be used to aid in legal investigations in the area and surrounding areas where work is limited, as well as to provide information on which forensically relevant species should be the subject of future research in the area.

Bayes factor: A useful tool to quantitatively evaluate and compare performance of multiple stature estimation equations.

When stature estimation of incomplete skeletal remains is necessary, researchers select an estimation equation which will produce the most accurate estimates. The purpose of this study is to propose that, given prior information of a target sample, the Bayes factor can be a useful tool to quantitatively evaluate and compare performance of multiple equations in this regard. This study also explores the best-performing equations to reconstruct statures of Korean War casualties with a demonstration of equation comparisons by the Bayes factor. Thirty-three sets of stature estimates were generated using different equations based on the osteometric data of the Korean War casualties. The distribution of each set was compared to that of the population (i.e., Korean servicemen during the Korean War) using the Bayes factors and posterior probabilities generated by the R codes in the LearnBayes package. A higher Bayes factor indicates a closer similarity between the two distributions under comparison. The equation with the highest Bayes factor in this study was Choi et al.'s (1997) humerus equation (bf=9.84), followed by the femur equation of the same authors (bf=5.3). The Bayesian approach has advantages over the traditional frequentist approach primarily based on the p-value. Particularly, the Bayes factor can provide practical interpretations on the models under comparison, which allows for a quantitative prioritization of different models. Researchers can obtain more accurate stature estimates of a target sample by using the equation of the highest Bayes factor.

Generating a Vertebrae-based Method to Discriminate between Korean and U.S. White Male Casualties from the Korean War.

Low recovery rate of intact crania in conflict-related contexts necessitates the use of postcranial elements for ancestry estimation. This study aimed to develop a new method to discriminate between Korean and U.S. White casualties from the Korean War using vertebrae. Maximum body heights of C2 through L5 were measured from 75 Korean and 51 U.S. males to generate discriminant functions. U.S. vertebral heights were statistically greater than Koreans in 18 out of 23 vertebrae (C2, C4-6, T3-6, and T8-L5). The functions with lumbar vertebrae tended to yield higher correct classification ratios (CCR) than those with cervical or thoracic vertebrae. Inclusion of the femur and tibia lengths in the vertebrae-involved functions enhanced the CCR's. Discriminant functions using the femur and tibia length were also presented. The results of this study are expected to complement the current practices of the Defense POW/MIA Accounting Agency and the Ministry of National Defense Agency for KIA Recovery and Identification, which are primarily based on cranial and dental morphology.

Investigation into Seasonal Scavenging Patterns of Raccoons on Human Decomposition.

Although raccoons are known as one of the most common scavengers in the U.S., scavenging by these animals has seldom been studied in terms of forensic significance. In this research, the seasonal pattern of raccoon scavenging and its effect on human decomposition was investigated using 178 human cadavers placed at the Anthropological Research Facility (ARF) of the University of Tennessee, Knoxville (UTK) between February 2011 and December 2013. The results reveal that (i) the frequency of scavenging increases during summer, (ii) scavenging occurs relatively immediately and lasts shorter in summer months, and (iii) scavenging influences the decomposition process by hollowing limbs and by disturbing insect activities, both of which eventually increases the chance of mummification on the affected body. This information is expected to help forensic investigators identify raccoon scavenging as well as make a more precise interpretation of the effect of raccoon scavenging on bodies at crime scenes.

Developing Korean-specific equations of stature estimation.

This study aims to develop Korean-specific equations for stature estimation and compare their performance to existing techniques. Due to a lack of appropriate reference samples in Korea, equations were generated using a hybrid method on 113 Korean unknown skeletons. In this approach, estimates using the anatomical method [1] were regarded as actual stature. Results revealed that new equations produced more accurate and precise estimates than previous techniques. In addition, due to consistent body proportions of Korean populations through time and space, new equations are applicable to Korean skeletons regardless of their temporal and geographic origins. For obtaining statures at death, particularly in a forensic context, an age correction factor, 0.0426 cm/year, should be applied.

No significant difference in the levels of dental fluctuating asymmetry between hypoplastic and non-hypoplastic skeletal groups from the Joseon Dynasty (mid 15th-early 20th century), South Korea.

OBJECTIVES: As part of efforts to explore the relationship between linear enamel hypoplasia (LEH) and dental fluctuating asymmetry (DFA), DFA levels were compared between a hypoplastic group and a non-hypoplastic group. Since both LEH and DFA are pathological indicators of environmental stress which are represented by teeth, it was hypothesized that the hypoplastic group would exhibit higher levels of DFA than the non-hypoplastic group. DESIGN: Total of 136 sets of Korean skeletal remains from the Joseon Dynasty (mid 15th-early 20th century, South Korea) were used. To test the hypothesis, DFA levels of both groups were compared by two-way ANOVA after examining some issues related to FA research such as measurement error, type of asymmetry, and size dependence. RESULT: Contrary to the anticipations of many relavant studies, the hypothesis of this study was not supported (F=3.469, p=0.063). That is, the DFA levels of the two groups did not differ significantly, which implies that LEH and DFA do not occur concordantly. CONCLUSION: As to the reason for the result of the present study, it was speculated that (1) different kinds and/or degrees of stressors may influence the occurrence of LEH and DFA, or (2) traditional measuring methods used for DFA research may not reflect true DFA levels. Based on this study, it is recommended that both LEH and DFA should be utilized and reported independently in future research on the environmental stress and nutritional status of human populations.

Self-assembly of molecular dumbbells into organized bundles with tunable size.

Dumbbell-shaped molecules consisting of three biphenyls connected through vinyl linkages as a conjugated rod segment and aliphatic polyether dendritic wedges with different cross-sections (i.e., dibranch (1), tetrabranch (2) and hexabranch (3)) were synthesized and characterized. The molecular dumbbells self-assemble into discrete bundles that organize into three-dimensional superlattices. Molecule 1, based on a dibranched dendritic wedge, organizes into primitive monoclinic-crystalline and body-centered, tetragonal liquid crystalline structures, while molecules 2 and 3, based on tetra- and hexabranched dendritic wedges, respectively, form only body-centered, tetragonal liquid crystalline structures. X-ray diffraction experiments and density measurements showed that the rod-bundle cross-sectional area decreases with increasing cross-section of the dendritic wedges. The influences of supramolecular structure on the bulk-state optical properties were investigated by measuring the UV/Vis absorption and steady state fluorescence spectroscopies. As the cross-section of the dendritic wedge of the molecule increases, the absorption and emission maxima shift to higher energy. This can be attributed to a quantum size effect of the three-dimensionally confined nanostructure.