Paleolakes and socioecological implications of last glacial "greening" of the South African interior.

Determining the timing and drivers of Pleistocene hydrological change in the interior of South Africa is critical for testing hypotheses regarding the presence, dynamics, and resilience of human populations. Combining geological data and physically based distributed hydrological modeling, we demonstrate the presence of large paleolakes in South Africa's central interior during the last glacial period, and infer a regional-scale invigoration of hydrological networks, particularly during marine isotope stages 3 and 2, most notably 55 to 39 ka and 34 to 31 ka. The resulting hydrological reconstructions further permit investigation of regional floral and fauna responses using a modern analog approach. These suggest that the climate change required to sustain these water bodies would have replaced xeric shrubland with more productive, eutrophic grassland or higher grass-cover vegetation, capable of supporting a substantial increase in ungulate diversity and biomass. The existence of such resource-rich landscapes for protracted phases within the last glacial period likely exerted a recurrent draw on human societies, evidenced by extensive pan-side artifact assemblages. Thus, rather than representing a perennially uninhabited hinterland, the central interior's underrepresentation in late Pleistocene archeological narratives likely reflects taphonomic biases stemming from a dearth of rockshelters and regional geomorphic controls. These findings suggest that South Africa's central interior experienced greater climatic, ecological, and cultural dynamism than previously appreciated and potential to host human populations whose archaeological signatures deserve systematic investigation.

Climatic controls on Later Stone Age human adaptation in Africa's southern Cape.

Africa's southern Cape is a key region for the evolution of our species, with early symbolic systems, marine faunal exploitation, and episodic production of microlithic stone tools taken as evidence for the appearance of distinctively complex human behavior. However, the temporally discontinuous nature of this evidence precludes ready assumptions of intrinsic adaptive benefit, and has encouraged diverse explanations for the occurrence of these behaviors, in terms of regional demographic, social and ecological conditions. Here, we present a new high-resolution multi-proxy record of environmental change that indicates that faunal exploitation patterns and lithic technologies track climatic variation across the last 22,300 years in the southern Cape. Conditions during the Last Glacial Maximum and deglaciation were humid, and zooarchaeological data indicate high foraging returns. By contrast, the Holocene is characterized by much drier conditions and a degraded resource base. Critically, we demonstrate that systems for technological delivery - or provisioning - were responsive to changing humidity and environmental productivity. However, in contrast to prevailing models, bladelet-rich microlithic technologies were deployed under conditions of high foraging returns and abandoned in response to increased aridity and less productive subsistence environments. This suggests that posited links between microlithic technologies and subsistence risk are not universal, and the behavioral sophistication of human populations is reflected in their adaptive flexibility rather than in the use of specific technological systems.

Food Security and Diet Among American Indians in the Midwest.

The purpose of this study was to determine levels of food security among American Indians (AI) living in the Midwest and possible correlations between food security levels and various health outcomes, diet, and demographic variables. This study used a cross-sectional design to determine health behaviors among AI. Participants (n = 362) were recruited by AI staff through various cultural community events in the Midwest, such as powwows and health fairs. Inclusion criteria included the following: age 18 years or older, self-identify as an AI, and willing to participate in the survey. Of all participants, 210 (58%) had either low or very low food security, with 96 in the very low category (26.5%). Participants with very low food security tended to have significantly more chronic conditions. Additional significant differences for very low food security existed by demographic variables, including having no insurance (p < 0.0001) or having a regular primary care provider (p = 0.0354). There was also a significant difference between food security levels and the consumption of fast food within the past week (p value = 0.0420), though no differences were found in fruit and vegetable consumption. AI in our sample had higher levels of food insecurity than those reported in the literature for other racial/ethnic groups. AI and non-Native health professionals should be aware of the gravity of food insecurity and the impact it has on overall health. Additional research is needed to determine specific aspects of food insecurity affecting different Native communities to develop appropriate interventions.

Coalescence and fragmentation in the late Pleistocene archaeology of southernmost Africa.

The later Pleistocene archaeological record of southernmost Africa encompasses several Middle Stone Age industries and the transition to the Later Stone Age. Through this period various signs of complex human behaviour appear episodically, including elaborate lithic technologies, osseous technologies, ornaments, motifs and abstract designs. Here we explore the regional archaeological record using different components of lithic technological systems to track the transmission of cultural information and the extent of population interaction within and between different climatic regions. The data suggest a complex set of coalescent and fragmented relationships between populations in different climate regions through the late Pleistocene, with maximum interaction (coalescence) during MIS 4 and MIS 2, and fragmentation during MIS 5 and MIS 3. Coalescent phases correlate with increases in the frequency of ornaments and other forms of symbolic expression, leading us to suggest that population interaction was a significant driver in their appearance.

Environmental influences on human innovation and behavioural diversity in southern Africa 92-80 thousand years ago.

Africa's Middle Stone Age preserves sporadic evidence for novel behaviours among early modern humans, prompting a range of questions about the influence of social and environmental factors on patterns of human behavioural evolution. Here we document a suite of novel adaptations dating approximately 92-80 thousand years before the present at the archaeological site Varsche Rivier 003 (VR003), located in southern Africa's arid Succulent Karoo biome. Distinctive innovations include the production of ostrich eggshell artefacts, long-distance transportation of marine molluscs and systematic use of heat shatter in stone tool production, none of which occur in coeval assemblages at sites in more humid, well-studied regions immediately to the south. The appearance of these novelties at VR003 corresponds with a period of reduced regional wind strength and enhanced summer rainfall, and all of them disappear with increasing winter rainfall dominance after 80 thousand years before the present, following which a pattern of technological similarity emerges at sites throughout the broader region. The results indicate complex and environmentally contingent processes of innovation and cultural transmission in southern Africa during the Middle Stone Age.

Eighteen-Year Review of Resident Performance on the American Urological Association In-Service Examination.

OBJECTIVE: To analyze national performance trends of urology residents on the American Urological Association In-Service Examination (ISE) over the last 18 years. METHODS: Trends in the national averages on the in-service examination for each year of residency training were collected and analyzed between the years 2000 and 2017. Mean and standard error were calculated for examination performance for each year of residency. Subject-specific performance was also determined for each given year of residency. Regression analysis was used to model trends in performance as a function of residency year. RESULTS: There was no significant difference in examination performance over 18 years with respect to each specific residency year. While there was an overall improvement in total scores with each advancing training year, year-over-year improvement in total examination performance began to plateau after Uro-2. Largest absolute performance improvement from Pre-Uro to Uro-4 were in subjects of "Urinary Diversion," "Obstructive Uropathy" and "Neoplasm." Scores in "Sexual Dysfunction, Endocrinopathy, Fertility Problems", and "Congenital Anomalies, Embryology, Anatomy" were consistently the lowest regardless of year of training. CONCLUSION: No significant change in performance was seen in each given year of residency over the 18-year period. There was improvement in overall scores as residents progressed through training, but scores plateaued after Uro-2 with minimal improvement between Uro-3 and Uro-4 years. Difference in subject scores suggests a disparity in educational focus in residency curricula and a potential need to improve the teaching strategies for subjects that tested less well throughout residency training.

The Limited Usefulness of Ultrasound Surveillance after Radical and Partial Nephrectomy for Renal Cell Carcinoma.

INTRODUCTION: We determined the usefulness of ultrasound compared to cross-sectional imaging in the detection of intra-abdominal recurrences after radical or partial nephrectomy for localized renal cell carcinoma. METHODS: We performed a retrospective review of 800 patients with clinically localized renal cell carcinoma who had undergone radical or partial nephrectomy between 2008 and 2015. Patients had at minimum 1 year of followup at our institution, at least 1 ultrasound during surveillance and no metastases at time of surgery. Our primary outcome was the rate of diagnosis of abdominal recurrence based on modality of surveillance. RESULTS: Median followup for the entire cohort was 37.5 months (range 12 to 166). Overall 396 and 404 patients underwent radical and partial nephrectomy, respectively, for localized renal cell carcinoma. There were 224 (57%) and 234 (58%) patients in the radical and partial nephrectomy cohorts, respectively, who had 2 or more ultrasounds performed during surveillance. In the radical and partial nephrectomy cohorts a total of 149 (19%) abdominal recurrences were detected, with only 8 (19%) initially detected by ultrasound. On the other hand, 15 (10%) recurrences were missed by a prior negative ultrasound. Furthermore, there were 8 false-positive ultrasound studies that cross-sectional imaging later ruled out. CONCLUSIONS: The low yield of ultrasound in the detection of abdominal recurrences after radical or partial nephrectomy for renal cell carcinoma raises questions as to its usefulness in routine surveillance.

Publisher Correction: A global database of Holocene paleotemperature records.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Author Correction: A global database of Holocene paleotemperature records.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

A global database of Holocene paleotemperature records.

A comprehensive database of paleoclimate records is needed to place recent warming into the longer-term context of natural climate variability. We present a global compilation of quality-controlled, published, temperature-sensitive proxy records extending back 12,000 years through the Holocene. Data were compiled from 679 sites where time series cover at least 4000 years, are resolved at sub-millennial scale (median spacing of 400 years or finer) and have at least one age control point every 3000 years, with cut-off values slackened in data-sparse regions. The data derive from lake sediment (51%), marine sediment (31%), peat (11%), glacier ice (3%), and other natural archives. The database contains 1319 records, including 157 from the Southern Hemisphere. The multi-proxy database comprises paleotemperature time series based on ecological assemblages, as well as biophysical and geochemical indicators that reflect mean annual or seasonal temperatures, as encoded in the database. This database can be used to reconstruct the spatiotemporal evolution of Holocene temperature at global to regional scales, and is publicly available in Linked Paleo Data (LiPD) format.

Publisher Correction: A global database of Holocene paleotemperature records.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Mid-Devensian climate and landscape in England: new data from Finningley, South Yorkshire.

While there is extensive evidence for the Late Devensian, less is known about Early and Middle Devensian (approx. 110-30 ka) climates and environments in the UK. The Greenland ice-core record suggests the UK should have endured multiple changes, but the terrestrial palaeo-record lacks sufficient detail for confirmation from sites in the British Isles. Data from deposits at Finningley, South Yorkshire, can help redress this. A channel with organic silts, dated 40 314-39 552 cal a BP, contained plant macrofossil and insect remains showing tundra with dwarf-shrub heath and bare ground. Soil moisture conditions varied from free draining to riparian, with ponds and wetter vegetated areas. The climate was probably low arctic with snow cover during the winter. Mutual climatic range (MCR), based on Coleoptera, shows the mean monthly winter temperatures of -22 to -2°C and summer ones of 8-14°C. Periglacial structures within the basal gravel deposits and beyond the glacial limits indicate cold-climate conditions, including permafrost. A compilation of MCR reconstructions for other Middle Devensian English sites shows that marine isotope stage 3-between 59 and 28 ka-experienced substantial variation in climate consistent with the Greenland ice-core record. The exact correlation is hampered by temporal resolution, but the Finningley site stadial at approximately 40 ka may correlate with the one of the Greenland stadials 7-11.

Past and future global transformation of terrestrial ecosystems under climate change.

Impacts of global climate change on terrestrial ecosystems are imperfectly constrained by ecosystem models and direct observations. Pervasive ecosystem transformations occurred in response to warming and associated climatic changes during the last glacial-to-interglacial transition, which was comparable in magnitude to warming projected for the next century under high-emission scenarios. We reviewed 594 published paleoecological records to examine compositional and structural changes in terrestrial vegetation since the last glacial period and to project the magnitudes of ecosystem transformations under alternative future emission scenarios. Our results indicate that terrestrial ecosystems are highly sensitive to temperature change and suggest that, without major reductions in greenhouse gas emissions to the atmosphere, terrestrial ecosystems worldwide are at risk of major transformation, with accompanying disruption of ecosystem services and impacts on biodiversity.

Diabetes Self-Management Behaviors among American Indians in the Midwestern United States.

The purpose of this study was to understand if American Indian adults with diabetes in the Midwest are similar to American Indian adults nationally in their self-management behaviors. This cross-sectional survey was conducted from May 2009 to April 2010 at powwows, health fairs, and other community events. The convenience sample self-selected into the study and answered questions via touch screen computer about diabetes self-management. Participants were significantly below the national average for American Indians in their adherence to self-management recommendations in daily foot checks (p=0.0035) and having had a dilated eye exam in the previous year (p=0.0002), despite being significantly more likely to have taken a diabetes self-management class (p<0.0001). They were similar to the national average for daily glucose checks and having had one or more hemoglobin A1C tests in the previous year. Participants were less likely to eat 5 or more servings of fruits or vegetables per day (p=0.0001), but more likely to achieve 150 minutes or more of physical activity per week (p=0.0001). Programs addressing self-care issues should be developed to help improve the self-management habits of American Indian adults with diabetes, with particular attention to activities outside of monitoring blood glucose and hemoglobin A1C levels.

Evaluation of biological sample preparation for immunosignature-based diagnostics.

To address the need for a universal system to assess health status, we previously described a method termed "immunosignaturing" which splays the entire humoral antibody repertoire across a peptide microarray. Two important issues relative to the potential broad use of immunosignatures are sample preparation and stability. In the present study, we compared the immunosignatures developed from serum, plasma, saliva, and antibodies eluted from blood dried onto filter paper. We found that serum and plasma provide identical immunosignatures. Immunosignatures derived from dried blood also correlated well with those from nondried serum from the same individual. Immunosignatures derived from dried blood were capable of distinguishing naïve mice from those infected with influenza virus. Saliva was applied to the arrays, and the IgA immunosignature correlated strongly with that from dried blood. Finally, we demonstrate that dried blood retains immunosignature information even when exposed to high temperature. This work expands the potential diagnostic uses for immunosignatures. These features suggest that different forms of archival samples can be used for diagnosis development and that in prospective studies samples can be easily procured.

Catastrophic drought in the Afro-Asian monsoon region during Heinrich event 1.

Between 15,000 and 18,000 years ago, large amounts of ice and meltwater entered the North Atlantic during Heinrich stadial 1. This caused substantial regional cooling, but major climatic impacts also occurred in the tropics. Here, we demonstrate that the height of this stadial, about 16,000 to 17,000 years ago (Heinrich event 1), coincided with one of the most extreme and widespread megadroughts of the past 50,000 years or more in the Afro-Asian monsoon region, with potentially serious consequences for Paleolithic cultures. Late Quaternary tropical drying commonly is attributed to southward drift of the intertropical convergence zone, but the broad geographic range of the Heinrich event 1 megadrought suggests that severe, systemic weakening of Afro-Asian rainfall systems also occurred, probably in response to sea surface cooling.