A Multi-isotope Investigation of Two Medieval German Populations: Insight into the Relationship Among Diet, Disease, and Tissue Isotopic Compositions

This thesis investigates the relationship between disease and bone collagen isotope compositions, and uses isotopic analyses of human and faunal bone to examine the diet and geographic associations of two medieval (9th to 16th century) German communities derived from urban (Regensburg, n=111) and rural (Dalheim, n=24) contexts. The first goal of this research was to determine the reliability of bone collagen isotopic compositions to characterize diet in unhealthy individuals. Examples of bone pathology were selected from two medieval samples and one modern/historic skeletal collection (n=49) in order to measure the extent to which pathology influences intra-skeletal isotopic variability. The carbon- and nitrogen-isotope compositions of collagen from pathological bone were compared to areas of related but unaffected bone. Individuals with osteomyelitic lesions or incompletely remodeled bone fractures demonstrated intra-skeletal variability in their nitrogen-isotope ratios. Overall, these differences were small, but larger than expected for normal intra-skeletal variability, and likely reflect changes in body metabolism that accompany chronic infection and severe trauma. This work also assessed the reliability of interpreting distinct diets from inter-individual differences in isotopic ratios. The Regensburg sample was used to test whether or not a relationship exists between various diseases and bone collagen nitrogen-isotope compositions when skeletal elements exhibiting pathology are avoided entirely during sampling. Although a number of conditions were evaluated, no disease processes were found to seriously modify original collagen nitrogen-isotope compositions. These results suggest that individuals with obvious bone pathology need not be excluded from isotopic investigations of paleodiet. The second goal of this research was to investigate the Regensburg and Dalheim populations in terms of diet and geographic identity using a multi-isotope analysis of human and faunal remains. At both sites, diets were based on C3 plants and/or plant-consumers, although minor consumption of millet (C4) cannot be ruled out. Differential access to dietary protein was observed in both communities, but the Regensburg residents likely consumed more foods from a higher trophic level (e.g., freshwater fish). The oxygen-isotope data for bone structural carbonate broadly associated most individuals with their region of burial but identifying specific geographic relocations within the region was not possible

Evaluating the Differential Impact of Teaching Assistant Training Programs on International Graduate Student Teaching

In this study, we compared the effects of a traditional teaching assistant (TA) training program to those of a specialized program, with a substantial intercultural component, for international graduate students. We expected both programs to result in an increase in international graduate students’ teaching self-efficacy, observed teaching effectiveness, and adoption of student-centred approaches to teaching, and we anticipated a greater degree of change for the participants in the specialized program. We found the expected increases for graduate students in both programs, with a larger increase in observed teaching effectiveness for students in the specialized program. We discuss the implications of tailoring TA training programs for international graduate students and of providing time and learning activities for the development of student-centred teaching and reflective practice

Lifespan benefits for the combination of rapamycin plus acarbose and for captopril in genetically heterogeneous mice.

Mice bred in 2017 and entered into the C2017 cohort were tested for possible lifespan benefits of (R/S)-1,3-butanediol (BD), captopril (Capt), leucine (Leu), the Nrf2-activating botanical mixture PB125, sulindac, syringaresinol, or the combination of rapamycin and acarbose started at 9 or 16 months of age (RaAc9, RaAc16). In male mice, the combination of Rapa and Aca started at 9 months and led to a longer lifespan than in either of the two prior cohorts of mice treated with Rapa only, suggesting that this drug combination was more potent than either of its components used alone. In females, lifespan in mice receiving both drugs was neither higher nor lower than that seen previously in Rapa only, perhaps reflecting the limited survival benefits seen in prior cohorts of females receiving Aca alone. Capt led to a significant, though small (4% or 5%), increase in female lifespan. Capt also showed some possible benefits in male mice, but the interpretation was complicated by the unusually low survival of controls at one of the three test sites. BD seemed to produce a small (2%) increase in females, but only if the analysis included data from the site with unusually short-lived controls. None of the other 4 tested agents led to any lifespan benefit. The C2017 ITP dataset shows that combinations of anti-aging drugs may have effects that surpass the benefits produced by either drug used alone, and that additional studies of captopril, over a wider range of doses, are likely to be rewarding

Isotopic anthropology of rural German medieval diet: intra- and inter-population variability

This study investigates the diet of an eleventh century CE parish community located in northwestern Germany. We assessed the isotopic compositions of human (n = 24) and faunal (n = 17) bone collagen (δ13Ccol, δ15Ncol) and human structural carbonate (δ13Csc) using skeletal material recovered from the Dalheim cemetery. Traditional interpretation of the isotopic data indicates that Dalheimresidents likely relied on a C3 plant-based diet and consumed some terrestrial animal products without evidence of marine resource input in the diet. Bivariate and multivariate models used as an additional means to assess diet indicate minor consumption of C4 plant foods in this community. The multivariate-isotope model identified regional similarities and differences in C4 plant/marine food consumption and in dietary protein sources by comparing data from Dalheim with those of other medieval sites from the published literature.We did not observe sex differences in this population but differences in δ15Ncol suggest that juveniles consumed the lowest trophic level protein

Immediate Sequential Bilateral Pediatric Vitreoretinal Surgery: An International Multicenter Study

To determine the feasibility and safety of bilateral simultaneous vitreoretinal surgery in pediatric patients. International, multicenter, interventional, retrospective case series. Patients 17 years of age or younger from 24 centers worldwide who underwent immediate sequential bilateral vitreoretinal surgery (ISBVS)-defined as vitrectomy, scleral buckle, or lensectomy using the vitreous cutter-performed in both eyes sequentially during the same anesthesia session. Clinical history, surgical details and indications, time under anesthesia, and intraoperative and postoperative ophthalmic and systemic adverse events were reviewed. Ocular and systemic adverse events. A total of 344 surgeries from 172 ISBVS procedures in 167 patients were included in the study. The mean age of the cohort was 1.3±2.6 years. Nonexclusive indications for ISBVS were rapidly progressive disease (74.6%), systemic morbidity placing the child at high anesthesia risk (76.0%), and residence remote from surgery location (30.2%). The most common diagnoses were retinopathy of prematurity (ROP; 72.7% [P < 0.01]; stage 3, 4.8%; stage 4A, 44.4%; stage 4B, 22.4%; stage 5, 26.4%), familial exudative vitreoretinopathy (7.0%), abusive head trauma (4.1%), persistent fetal vasculature (3.5%), congenital cataract (1.7%), posterior capsular opacification (1.7%), rhegmatogenous retinal detachment (1.7%), congenital X-linked retinoschisis (1.2%), Norrie disease (2.3%), and viral retinitis (1.2%). Mean surgical time was 143±59 minutes for both eyes. Higher ROP stage correlated with longer surgical time (P = 0.02). There were no reported intraoperative ocular complications. During the immediate postoperative period, 2 eyes from different patients demonstrated unilateral vitreous hemorrhage (0.6%). No cases of endophthalmitis, choroidal hemorrhage, or hypotony occurred. Mean total anesthesia time was 203±87 minutes. There were no cases of anesthesia-related death, malignant hyperthermia, anaphylaxis, or cardiac event. There was 1 case of reintubation (0.6%) and 1 case of prolonged oxygen desaturation (0.6%). Mean follow-up after surgery was 103 weeks, and anatomic success and globe salvage rates were 89.8% and 98.0%, respectively. This study found ISBVS to be a feasible and safe treatment paradigm for pediatric patients with bilateral vitreoretinal pathologic features when repeated general anesthesia is undesirable or impractical